Space Shuttle Orbiter Approach and Landing Test Evaluation Report. Captive-Active Flight Test Summary

NASA Technical Reports Server (NTRS)

1977-01-01

Captive-active tests consisted of three mated carrier aircraft/Orbiter flights with an active manned Orbiter. The objectives of this series of flights were to (1) verify the separation profile, (2) verify the integrated structure, aerodynamics, and flight control system, (3) verify Orbiter integrated system operations, and (4) refine and finalize carrier aircraft, Orbiter crew, and ground procedures in preparation for free flight tests. A summary description of the flights is presented with assessments of flight test requirements, and of the performance operations, and of significant flight anomalies is included.

Orion Flight Test Architecture Benefits of MBSE Approach

NASA Technical Reports Server (NTRS)

Reed, Don; Simpson, Kim

2012-01-01

Exploration Flight Test 1 (EFT-1) is an unmanned first orbital flight test of the Multi Purpose Crew Vehicle (MPCV) Mission s purpose is to: Test Orion s ascent, on-orbit and entry capabilities Monitor critical activities Provide ground control in support of contingency scenarios Requires development of a large scale end-to-end information system network architecture To effectively communicate the scope of the end-to-end system a model-based system engineering approach was chosen.

Development Overview of the Revised NASA Ultra Long Duration Balloon

NASA Technical Reports Server (NTRS)

Cathey, H. M.; Gregory, D; Young, L.; Pierce, D.

2006-01-01

The development of the National Aeronautics and Space Administration s (NASA) Ultra Long Duration Balloon (ULDB) has made significant strides in addressing the deployment issues experienced in the scaling up of the balloon structure. This paper concentrates on the super-pressure balloon developments that have been, and are currently being planned by the NASA Balloon Program Office at Goddard Space Flight Center s Wallops Flight Facility. The goal of the NASA ULDB development project is to attempt to extend the potential flight durations for large scientific balloon payloads. A summary of the February 2005 test flight from Ft. Sumner, New Mexico will be presented. This test flight spurred a number of investigations and advancements for this project. The development path has pursued some new approaches in the design, analysis, and testing of the balloons. New issues have been ideEti6ed throu& both analysis md testing. These have been addressed in the design stage before the next balloon construction was begun. This paper will give an overview of the recent history for this effort and the development approach pursued for ULDB. A description of the balloon design, including the modifications made as a result of the lessons learned, will be presented. Areas to be presented include the design approach, deployment issues that have been encountered and the proposed solutions, ground testing, photogrammetry, and an analysis overview. Test flight planning and considerations will be presented including test flight safety. An extended duration test flight of the National Aeronautics and Space Administration s Ultra Long Duration Balloon is planned for the May/June 2006 time frame. This flight is expected to fly from Sweden to either Canada or Alaska. Preliminary results of this flight will be presented as available. Future plans for both ground testing and additional test flights will also be presented. Goals of the future test flights, which are staged in increments of increasing suspended load and altitude, will be presented. This will include the projected balloon volumes, payload capabilities, test flight locations, and proposed flight schedule.

Design and Development of a Rapid Research, Design, and Development Platform for In-Situ Testing of Tools and Concepts for Trajectory-Based Operations

NASA Technical Reports Server (NTRS)

Underwood, Matthew C.

2017-01-01

To provide justification for equipping a fleet of aircraft with avionics capable of supporting trajectory-based operations, significant flight testing must be accomplished. However, equipping aircraft with these avionics and enabling technologies to communicate the clearances required for trajectory-based operations is cost-challenging using conventional avionics approaches. This paper describes an approach to minimize the costs and risks of flight testing these technologies in-situ, discusses the test-bed platform developed, and highlights results from a proof-of-concept flight test campaign that demonstrates the feasibility and efficiency of this approach.

Evaluating the dynamic response of in-flight thrust calculation techniques during throttle transients

NASA Technical Reports Server (NTRS)

Ray, Ronald J.

1994-01-01

New flight test maneuvers and analysis techniques for evaluating the dynamic response of in-flight thrust models during throttle transients have been developed and validated. The approach is based on the aircraft and engine performance relationship between thrust and drag. Two flight test maneuvers, a throttle step and a throttle frequency sweep, were developed and used in the study. Graphical analysis techniques, including a frequency domain analysis method, were also developed and evaluated. They provide quantitative and qualitative results. Four thrust calculation methods were used to demonstrate and validate the test technique. Flight test applications on two high-performance aircraft confirmed the test methods as valid and accurate. These maneuvers and analysis techniques were easy to implement and use. Flight test results indicate the analysis techniques can identify the combined effects of model error and instrumentation response limitations on the calculated thrust value. The methods developed in this report provide an accurate approach for evaluating, validating, or comparing thrust calculation methods for dynamic flight applications.

Flight-test evaluation of STOL control and flight director concepts in a powered-lift aircraft flying curved decelerating approaches

NASA Technical Reports Server (NTRS)

Hindson, W. S.; Hardy, G. H.; Innis, R. C.

1981-01-01

Flight tests were carried out to assess the feasibility of piloted steep curved, and decelerating approach profiles in powered lift STOL aircraft. Several STOL control concepts representative of a variety of aircraft were evaluated in conjunction with suitably designed flight directions. The tests were carried out in a real navigation environment, employed special electronic cockpit displays, and included the development of the performance achieved and the control utilization involved in flying 180 deg turning, descending, and decelerating approach profiles to landing. The results suggest that such moderately complex piloted instrument approaches may indeed be feasible from a pilot acceptance point of view, given an acceptable navigation environment. Systems with the capability of those used in this experiment can provide the potential of achieving instrument operations on curved, descending, and decelerating landing approaches to weather minima corresponding to CTOL Category 2 criteria, while also providing a means of realizing more efficient operations during visual flight conditions.

Functional testing of space flight induced changes in tonic motor control by using limb-attached excitation and load devices

NASA Astrophysics Data System (ADS)

Gallasch, Eugen; Kozlovskaya, Inessa

2007-02-01

Long term space flights induce atrophy and contractile changes on postural muscles such effecting tonic motor control. Functional testing of tonic motor control structures is a challenge because of the difficulties to deliver appropriate test forces on crew members. In this paper we propose two approaches for functional testing by using limb attached loading devices. The first approach is based on a frequency and amplitude controllable moving magnet exciter to deliver sinusoidal test forces during limb postures. The responding limb deflection is recorded by an embedded accelerometer to obtain limb impedance. The second approach is based on elastic limb loading to evoke self-excited oscillations during arm extensions. Here the contraction force at the oscillation onset provides information about limb stiffness. The rationale for both testing approaches is based on Feldman's λ-model. An arm expander based on the second approach was probed in a 6-month MIR space flight. The results obtained from the load oscillations, confirmed that this device is well suited to capture space flight induced neuromuscular changes.

General Aviation Flight Test of Advanced Operations Enabled by Synthetic Vision

NASA Technical Reports Server (NTRS)

Glaab, Louis J.; Hughhes, Monica F.; Parrish, Russell V.; Takallu, Mohammad A.

2014-01-01

A flight test was performed to compare the use of three advanced primary flight and navigation display concepts to a baseline, round-dial concept to assess the potential for advanced operations. The displays were evaluated during visual and instrument approach procedures including an advanced instrument approach resembling a visual airport traffic pattern. Nineteen pilots from three pilot groups, reflecting the diverse piloting skills of the General Aviation pilot population, served as evaluation subjects. The experiment had two thrusts: 1) an examination of the capabilities of low-time (i.e., <400 hours), non-instrument-rated pilots to perform nominal instrument approaches, and 2) an exploration of potential advanced Visual Meteorological Conditions (VMC)-like approaches in Instrument Meteorological Conditions (IMC). Within this context, advanced display concepts are considered to include integrated navigation and primary flight displays with either aircraft attitude flight directors or Highway In The Sky (HITS) guidance with and without a synthetic depiction of the external visuals (i.e., synthetic vision). Relative to the first thrust, the results indicate that using an advanced display concept, as tested herein, low-time, non-instrument-rated pilots can exhibit flight-technical performance, subjective workload and situation awareness ratings as good as or better than high-time Instrument Flight Rules (IFR)-rated pilots using Baseline Round Dials for a nominal IMC approach. For the second thrust, the results indicate advanced VMC-like approaches are feasible in IMC, for all pilot groups tested for only the Synthetic Vision System (SVS) advanced display concept.

KSC-2013-3561

NASA Image and Video Library

2013-08-15

DRYDEN FLIGHT RESEARCH CENTER, Calif. - Simulation technicians Brent Bieber, left, and Dennis Pitts install a boilerplate Dream Chaser canopy structure over the cockpit of a flight simulator in the simulation laboratory at NASA's Dryden Flight Research Center in California. The modification will give Dream Chaser pilot-astronauts a more representative view of the actual flight profiles the spacecraft would fly during piloted approach and landing tests. Sierra Nevada Corporation's Space Systems division is conducting uncrewed captive- and free-flight approach and landing tests of its Dream Chaser at Dryden during the summer and fall. Photo credit: NASA/Ken Ulbrich

Flight Test of an Adaptive Controller and Simulated Failure/Damage on the NASA NF-15B

NASA Technical Reports Server (NTRS)

Buschbacher, Mark; Maliska, Heather

2006-01-01

The method of flight-testing the Intelligent Flight Control System (IFCS) Second Generation (Gen-2) project on the NASA NF-15B is herein described. The Gen-2 project objective includes flight-testing a dynamic inversion controller augmented by a direct adaptive neural network to demonstrate performance improvements in the presence of simulated failure/damage. The Gen-2 objectives as implemented on the NASA NF-15B created challenges for software design, structural loading limitations, and flight test operations. Simulated failure/damage is introduced by modifying control surface commands, therefore requiring structural loads measurements. Flight-testing began with the validation of a structural loads model. Flight-testing of the Gen-2 controller continued, using test maneuvers designed in a sequenced approach. Success would clear the new controller with respect to dynamic response, simulated failure/damage, and with adaptation on and off. A handling qualities evaluation was conducted on the capability of the Gen-2 controller to restore aircraft response in the presence of a simulated failure/damage. Control room monitoring of loads sensors, flight dynamics, and controller adaptation, in addition to postflight data comparison to the simulation, ensured a safe methodology of buildup testing. Flight-testing continued without major incident to accomplish the project objectives, successfully uncovering strengths and weaknesses of the Gen-2 control approach in flight.

Flight-Test Evaluation of Flutter-Prediction Methods

NASA Technical Reports Server (NTRS)

Lind, RIck; Brenner, Marty

2003-01-01

The flight-test community routinely spends considerable time and money to determine a range of flight conditions, called a flight envelope, within which an aircraft is safe to fly. The cost of determining a flight envelope could be greatly reduced if there were a method of safely and accurately predicting the speed associated with the onset of an instability called flutter. Several methods have been developed with the goal of predicting flutter speeds to improve the efficiency of flight testing. These methods include (1) data-based methods, in which one relies entirely on information obtained from the flight tests and (2) model-based approaches, in which one relies on a combination of flight data and theoretical models. The data-driven methods include one based on extrapolation of damping trends, one that involves an envelope function, one that involves the Zimmerman-Weissenburger flutter margin, and one that involves a discrete-time auto-regressive model. An example of a model-based approach is that of the flutterometer. These methods have all been shown to be theoretically valid and have been demonstrated on simple test cases; however, until now, they have not been thoroughly evaluated in flight tests. An experimental apparatus called the Aerostructures Test Wing (ATW) was developed to test these prediction methods.

Advanced Space Transportation Program (ASTP)

NASA Image and Video Library

2003-07-01

NASA's X-37 Approach and Landing Test Vehicle is installed is a structural facility at Boeing's Huntington Beach, California plant. Tests, completed in July, were conducted to verify the structural integrity of the vehicle in preparation for atmospheric flight tests. Atmospheric flight tests of the Approach and Landing Test Vehicle are scheduled for 2004 and flight tests of the Orbital Vehicle are scheduled for 2006. The X-37 experimental launch vehicle is roughly 27.5 feet (8.3 meters) long and 15 feet (4.5 meters) in wingspan. It's experiment bay is 7 feet (2.1 meters) long and 4 feet (1.2 meters) in diameter. Designed to operate in both the orbital and reentry phases of flight, the X-37 will increase both safety and reliability, while reducing launch costs from $10,000 per pound to $1,000.00 per pound. The X-37 program is managed by the Marshall Space Flight Center and built by the Boeing Company.

Simulation and flight test evaluation of head-up-display guidance for harrier approach transitions

NASA Technical Reports Server (NTRS)

Dorr, D. W.; Moralez, E., III; Merrick, V. K.

1994-01-01

Position and speed guidance displays for STOVL aircraft curved, decelerating approaches to hover and vertical landing have been evaluated for their effectiveness in reducing pilot workload and improving performance. The NASA V/STOL Systems Research Aircraft, a modified YAV-8B Harrier prototype, was used to evaluate the displays in flight, whereas the NASA Ames Vertical Motion Simulator was used to extend the flight test results to instrument meteorological conditions (IMC) and to examine performance in various conditions of wind and turbulence. The simulation data showed close correlation with the flight test data, and both demonstrated the feasibility of the displays. With the exception of the hover task in zero visibility, which was level-3, averaged Copper-Harper handling qualities ratings given during simulation were level-2 for both the approach task and the hover task in all conditions. During flight tests in calm and clear conditions, the displays also gave rise to level-2 handling qualities ratings. Pilot opinion showed that the guidance displays would be useful in visual flight, especially at night, as well as in IMC.

X-56A MUTT: Aeroservoelastic Modeling

NASA Technical Reports Server (NTRS)

Ouellette, Jeffrey A.

2015-01-01

For the NASA X-56a Program, Armstrong Flight Research Center has been developing a set of linear states space models that integrate the flight dynamics and structural dynamics. These high order models are needed for the control design, control evaluation, and test input design. The current focus has been on developing stiff wing models to validate the current modeling approach. The extension of the modeling approach to the flexible wings requires only a change in the structural model. Individual subsystems models (actuators, inertial properties, etc.) have been validated by component level ground tests. Closed loop simulation of maneuvers designed to validate the flight dynamics of these models correlates very well flight test data. The open loop structural dynamics are also shown to correlate well to the flight test data.

Dynamic stability and handling qualities tests on a highly augmented, statically unstable airplane

NASA Technical Reports Server (NTRS)

Gera, Joseph; Bosworth, John T.

1987-01-01

Initial envelope clearance and subsequent flight testing of a new, fully augmented airplane with an extremely high degree of static instability can place unusual demands on the flight test approach. Previous flight test experience with these kinds of airplanes is very limited or nonexistent. The safe and efficient flight testing may be further complicated by a multiplicity of control effectors that may be present on this class of airplanes. This paper describes some novel flight test and analysis techniques in the flight dynamics and handling qualities area. These techniques were utilized during the initial flight envelope clearance of the X-29A aircraft and were largely responsible for the completion of the flight controls clearance program without any incidents or significant delays.

Enterprise Separates from 747 SCA for First Tailcone off Free Flight

NASA Technical Reports Server (NTRS)

1977-01-01

The Space Shuttle prototype Enterprise rises from NASA's 747 Shuttle Carrier Aircraft (SCA) to begin a powerless glide flight back to NASA's Dryden Flight Research Center, Edwards, California, on its fourth of the five free flights in the shuttle program's Approach and Landing Tests (ALT), 12 October 1977. The tests were carried out at Dryden to verify the aerodynamic and control characteristics of the orbiters in preparation for the first space mission with the orbiter Columbia in April 1981. The Space Shuttle Approach and Landings Tests (ALT) program allowed pilots and engineers to learn how the Space Shuttle and the modified Boeing 747 Shuttle Carrier Aircraft (SCA) handled during low-speed flight and landing. The Enterprise, a prototype of the Space Shuttles, and the SCA were flown to conduct the approach and landing tests at the NASA Dryden Flight Research Center, Edwards, California, from February to October 1977. The first flight of the program consisted of the Space Shuttle Enterprise attached to the Shuttle Carrier Aircraft. These flights were to determine how well the two vehicles flew together. Five 'captive-inactive' flights were flown during this first phase in which there was no crew in the Enterprise. The next series of captive flights was flown with a flight crew of two on board the prototype Space Shuttle. Only three such flights proved necessary. This led to the free-flight test series. The free-flight phase of the ALT program allowed pilots and engineers to learn how the Space Shuttle handled in low-speed flight and landing attitudes. For these landings, the Enterprise was flown by a crew of two after it was released from the top of the SCA. The vehicle was released at altitudes ranging from 19,000 to 26,000 feet. The Enterprise had no propulsion system, but its first four glides to the Rogers Dry Lake runway provided realistic, in-flight simulations of how subsequent Space Shuttles would be flown at the end of an orbital mission. The fifth approach and landing test, with the Enterprise landing on the Edwards Air Force Base concrete runway, revealed a problem with the Space Shuttle flight control system that made it susceptible to Pilot-Induced Oscillation (PIO), a potentially dangerous control problem during a landing. Further research using other NASA aircraft, especially the F-8 Digital-Fly-By-Wire aircraft, led to correction of the PIO problem before the first orbital flight. The Enterprise's last free-flight was October 26, 1977, after which it was ferried to other NASA centers for ground-based flight simulations that tested Space Shuttle systems and structure.

Software control and system configuration management: A systems-wide approach

NASA Technical Reports Server (NTRS)

Petersen, K. L.; Flores, C., Jr.

1984-01-01

A comprehensive software control and system configuration management process for flight-crucial digital control systems of advanced aircraft has been developed and refined to insure efficient flight system development and safe flight operations. Because of the highly complex interactions among the hardware, software, and system elements of state-of-the-art digital flight control system designs, a systems-wide approach to configuration control and management has been used. Specific procedures are implemented to govern discrepancy reporting and reconciliation, software and hardware change control, systems verification and validation testing, and formal documentation requirements. An active and knowledgeable configuration control board reviews and approves all flight system configuration modifications and revalidation tests. This flexible process has proved effective during the development and flight testing of several research aircraft and remotely piloted research vehicles with digital flight control systems that ranged from relatively simple to highly complex, integrated mechanizations.

Adaptive Flight Control Research at NASA

NASA Technical Reports Server (NTRS)

Motter, Mark A.

2008-01-01

A broad overview of current adaptive flight control research efforts at NASA is presented, as well as some more detailed discussion of selected specific approaches. The stated objective of the Integrated Resilient Aircraft Control Project, one of NASA s Aviation Safety programs, is to advance the state-of-the-art of adaptive controls as a design option to provide enhanced stability and maneuverability margins for safe landing in the presence of adverse conditions such as actuator or sensor failures. Under this project, a number of adaptive control approaches are being pursued, including neural networks and multiple models. Validation of all the adaptive control approaches will use not only traditional methods such as simulation, wind tunnel testing and manned flight tests, but will be augmented with recently developed capabilities in unmanned flight testing.

Flight testing of airbreathing hypersonic vehicles

NASA Technical Reports Server (NTRS)

Hicks, John W.

1993-01-01

Using the scramjet engine as the prime example of a hypersonic airbreathing concept, this paper reviews the history of and addresses the need for hypersonic flight tests. It also describes how such tests can contribute to the development of airbreathing technology. Aspects of captive-carry and free-flight concepts are compared. An incremental flight envelope expansion technique for manned flight vehicles is also described. Such critical issues as required instrumentation technology and proper scaling of experimental devices are addressed. Lastly, examples of international flight test approaches, existing programs, or concepts currently under study, development, or both, are given.

Development, design, and flight test evaluation of a continuous descent approach procedure for nighttime operation at Louisville International Airport.

DOT National Transportation Integrated Search

2006-01-09

The design and flight test of a Continuous Descent Approach (CDA) : procedure for regular nighttime operation at Louisville : International Airport are described in this report. Results of : the analyses of aircraft and FMS performance indicate that ...

The design, development, and flight test results of the Boeing 737 aircraft antennas for the ICAO demonstration of the TRSB microwave landing system

NASA Technical Reports Server (NTRS)

Campbell, T. G.; White, W. E.; Gilreath, M. C.

1976-01-01

The Research Support Flight System, a modified Boeing 737, was used to evaluate the performance of several aircraft antennas and locations for the Time Reference Scanning Beam (TRSB) Microwave Landing System (MLS). These tests were conducted at the National Aviation Facilities Experimental Center (NAFEC), Atlantic City, New Jersey on December 18, 1975. The flight tests measured the signal strength and all pertinent MLS data during a straight-in approach, a racetrack approach, and ICAO approach profiles using the independent antenna-receiver combinations simultaneously on the aircraft. Signal drop-outs were experienced during the various approaches but only a small percentage could be attributed to antenna pattern effects.

Flight Test of a Propulsion-Based Emergency Control System on the MD-11 Airplane with Emphasis on the Lateral Axis

NASA Technical Reports Server (NTRS)

Burken, John J.; Burcham, Frank W., Jr.; Maine, Trindel A.; Feather, John; Goldthorpe, Steven; Kahler, Jeffrey A.

1996-01-01

A large, civilian, multi-engine transport MD-11 airplane control system was recently modified to perform as an emergency backup controller using engine thrust only. The emergency backup system, referred to as the propulsion-controlled aircraft (PCA) system, would be used if a major primary flight control system fails. To allow for longitudinal and lateral-directional control, the PCA system requires at least two engines and is implemented through software modifications. A flight-test program was conducted to evaluate the PCA system high-altitude flying characteristics and to demonstrate its capacity to perform safe landings. The cruise flight conditions, several low approaches and one landing without any aerodynamic flight control surface movement, were demonstrated. This paper presents results that show satisfactory performance of the PCA system in the longitudinal axis. Test results indicate that the lateral-directional axis of the system performed well at high attitude but was sluggish and prone to thermal upsets during landing approaches. Flight-test experiences and test techniques are also discussed with emphasis on the lateral-directional axis because of the difficulties encountered in flight test.

Determination of UAV pre-flight Checklist for flight test purpose using qualitative failure analysis

NASA Astrophysics Data System (ADS)

Hendarko; Indriyanto, T.; Syardianto; Maulana, F. A.

2018-05-01

Safety aspects are of paramount importance in flight, especially in flight test phase. Before performing any flight tests of either manned or unmanned aircraft, one should include pre-flight checklists as a required safety document in the flight test plan. This paper reports on the development of a new approach for determination of pre-flight checklists for UAV flight test based on aircraft’s failure analysis. The Lapan’s LSA (Light Surveillance Aircraft) is used as a study case, assuming this aircraft has been transformed into the unmanned version. Failure analysis is performed on LSA using fault tree analysis (FTA) method. Analysis is focused on propulsion system and flight control system, which fail of these systems will lead to catastrophic events. Pre-flight checklist of the UAV is then constructed based on the basic causes obtained from failure analysis.

The Building Blocks for JWST I and T (Integrations and Test) to Operations - From Simulator to Flight Units

NASA Technical Reports Server (NTRS)

Fatig, Curtis; Ochs, William; Johns, Alan; Seaton, Bonita; Adams, Cynthia; Wasiak, Francis; Jones, Ronald; Jackson, Wallace

2012-01-01

The James Webb Space Telescope (JWST) Project has an extended integration and test (I&T) phase due to long procurement and development times of various components as well as recent launch delays. The JWST Ground Segment and Operations group has developed a roadmap of the various ground and flight elements and their use in the various JWST I&T test programs. The JWST Project s building block approach to the eventual operational systems, while not new, is complex and challenging; a large-scale mission like JWST involves international partners, many vendors across the United States, and competing needs for the same systems. One of the challenges is resource balancing so simulators and flight products for various elements congeal into integrated systems used for I&T and flight operations activities. This building block approach to an incremental buildup provides for early problem identification with simulators and exercises the flight operations systems, products, and interfaces during the JWST I&T test programs. The JWST Project has completed some early I&T with the simulators, engineering models and some components of the operational ground system. The JWST Project is testing the various flight units as they are delivered and will continue to do so for the entire flight and operational system. The JWST Project has already and will continue to reap the value of the building block approach on the road to launch and flight operations.

Approach & Landing Test (ALT) - Shuttle Free-Flight (FF)-2 - New Release

NASA Image and Video Library

1977-09-13

S77-28141 (13 Sept 1977) --- The shuttle Orbiter 101 "Enterprise" makes a slight turn and bank maneuver during the second free flight of the Shuttle Approach and Landing Tests (ALT) conducted on September 13, 1977, at the Dryden Flight Research Center in Southern California. The "Enterprise" separated from the NASA 747 carrier aircraft and landed following a five-minute, 28-second unpowered flight. The Orbiter 101 crew was astronauts Joe H. Engle, commander, and Richard H. Truly, pilot. The ALT free flights are designed to verify orbiter subsonic airworthiness, integrated systems operations and pilot-guided approach and landing capability and satisfy prerequisites to automatic flight control and navigation mode. The orbiter soars above the dry California desert in this post-separation view. Photographer Bill Blunck of JSC's Photographic Technology Laboratory took this picture while riding in T-38 chase plane number two. He used a 70mm Hasselblad camera with an 80mm lens.

Approach & Landing Test (ALT) - Shuttle Free-Flight (FF)-2, News Release

NASA Image and Video Library

1977-09-13

S77-28138 (13 Sept 1977) --- The shuttle Orbiter 101 "Enterprise" makes a slight turn and bank maneuver during the second free flight of the Shuttle Approach and Landing Tests (ALT) conducted on September 13, 1977, at the Dryden Flight Research Center in Southern California. The "Enterprise" separated from the NASA 747 carrier aircraft and landed following a five-minute, 28-second unpowered flight. The Orbiter 101 crew was astronauts Joe H. Engle, commander, and Richard H. Truly, pilot. The ALT free flights are designed to verify orbiter subsonic airworthiness, integrated systems operations and pilot-guided approach and landing capability and satisfy prerequisites to automatic flight control and navigation mode. The orbiter soars above the dry California desert in this post-separation view. Astronaut C. Gordon Fullerton took this picture while riding in T-38 chase plane number one. He used a 35mm Nikon camera with a 50mm lens.

First Shuttle/747 Captive Flight

NASA Technical Reports Server (NTRS)

1977-01-01

The Space Shuttle prototype Enterprise rides smoothly atop NASA's first Shuttle Carrier Aircraft (SCA), NASA 905, during the first of the shuttle program's Approach and Landing Tests (ALT) at the Dryden Flight Research Center, Edwards, California, in 1977. During the nearly one year-long series of tests, Enterprise was taken aloft on the SCA to study the aerodynamics of the mated vehicles and, in a series of five free flights, tested the glide and landing characteristics of the orbiter prototype. In this photo, the main engine area on the aft end of Enterprise is covered with a tail cone to reduce aerodynamic drag that affects the horizontal tail of the SCA, on which tip fins have been installed to increase stability when the aircraft carries an orbiter. The Space Shuttle Approach and Landings Tests (ALT) program allowed pilots and engineers to learn how the Space Shuttle and the modified Boeing 747 Shuttle Carrier Aircraft (SCA) handled during low-speed flight and landing. The Enterprise, a prototype of the Space Shuttles, and the SCA were flown to conduct the approach and landing tests at the NASA Dryden Flight Research Center, Edwards, California, from February to October 1977. The first flight of the program consisted of the Space Shuttle Enterprise attached to the Shuttle Carrier Aircraft. These flights were to determine how well the two vehicles flew together. Five 'captive-inactive' flights were flown during this first phase in which there was no crew in the Enterprise. The next series of captive flights was flown with a flight crew of two on board the prototype Space Shuttle. Only three such flights proved necessary. This led to the free-flight test series. The free-flight phase of the ALT program allowed pilots and engineers to learn how the Space Shuttle handled in low-speed flight and landing attitudes. For these landings, the Enterprise was flown by a crew of two after it was released from the top of the SCA. The vehicle was released at altitudes ranging from 19,000 to 26,000 feet. The Enterprise had no propulsion system, but its first four glides to the Rogers Dry Lake runway provided realistic, in-flight simulations of how subsequent Space Shuttles would be flown at the end of an orbital mission. The fifth approach and landing test, with the Enterprise landing on the Edwards Air Force Base concrete runway, revealed a problem with the Space Shuttle flight control system that made it susceptible to Pilot-Induced Oscillation (PIO), a potentially dangerous control problem during a landing. Further research using other NASA aircraft, especially the F-8 Digital-Fly-By-Wire aircraft, led to correction of the PIO problem before the first orbital flight. The Enterprise's last free-flight was October 26, 1977, after which it was ferried to other NASA centers for ground-based flight simulations that tested Space Shuttle systems and structure.

Advanced Space Transportation Program (ASTP)

NASA Image and Video Library

2003-07-01

NASA's X-37 Approach and Landing Test Vehicle is installed is a structural facility at Boeing's Huntington Beach, California plant, where technicians make adjustments to composite panels. Tests, completed in July, were conducted to verify the structural integrity of the vehicle in preparation for atmospheric flight tests. Atmospheric flight tests of the Approach and Landing Test Vehicle are scheduled for 2004 and flight tests of the Orbital Vehicle are scheduled for 2006. The X-37 experimental launch vehicle is roughly 27.5 feet (8.3 meters) long and 15 feet (4.5 meters) in wingspan. It's experiment bay is 7 feet (2.1 meters) long and 4 feet (1.2 meters) in diameter. Designed to operate in both the orbital and reentry phases of flight, the X-37 will increase both safety and reliability, while reducing launch costs from $10,000 per pound to $1,000.00 per pound. The X-37 program is managed by the Marshall Space Flight Center and built by the Boeing Company.

NASA/ARMY/BELL XV-15 Tiltrotor Low-Noise Terminal Area Operations Flight Research Program

NASA Technical Reports Server (NTRS)

Edwards, Bryan D.; Conner, David A.; Decker, William A.; Marcolini, Michael A.; Klein, Peter D.

2001-01-01

To evaluate the noise reduction potential for tiltrotor aircraft, a series of three XV- 15 acoustic flight tests were conducted over a five-year period by a NASA/Army/Bell Helicopter team. Lower hemispherical noise characteristics for a wide range of steady-state terminal area type operating conditions were measured during the Phase I test and indicated that the takeoff and level flight conditions were not significant contributors to the total noise of tiltrotor operations. Phase I results were also used to design low-noise approach profiles that were tested later during the Phase 2 and Phase 3 tests. These latter phases used large area microphone arrays to directly measure ground noise footprints. Approach profiles emphasized noise reduction while maintaining handling qualities sufficient for tiltrotor commercial passenger ride comfort and flight safety under Instrument Flight Rules (IFR) conditions. This paper will discuss the weather, aircraft, tracking, guidance, and acoustic instrumentation systems, as well as the approach profile design philosophy, and the overall test program philosophy. Acoustic results are presented to document the variation in tiltrotor noise due to changes in operating condition, indicating the potential for significant noise reduction using the unique tiltrotor capability of nacelle tilt. Recommendations are made for a final XV-15 test to define the acoustic benefits of the automated approach capability which has recently been added to this testbed aircraft.

High Stability Engine Control (HISTEC) Flight Test Results

NASA Technical Reports Server (NTRS)

Southwick, Robert D.; Gallops, George W.; Kerr, Laura J.; Kielb, Robert P.; Welsh, Mark G.; DeLaat, John C.; Orme, John S.

1998-01-01

The High Stability Engine Control (HISTEC) Program, managed and funded by the NASA Lewis Research Center, is a cooperative effort between NASA and Pratt & Whitney (P&W). The program objective is to develop and flight demonstrate an advanced high stability integrated engine control system that uses real-time, measurement-based estimation of inlet pressure distortion to enhance engine stability. Flight testing was performed using the NASA Advanced Controls Technologies for Integrated Vehicles (ACTIVE) F-15 aircraft at the NASA Dryden Flight Research Center. The flight test configuration, details of the research objectives, and the flight test matrix to achieve those objectives are presented. Flight test results are discussed that show the design approach can accurately estimate distortion and perform real-time control actions for engine accommodation.

The NASA super pressure balloon - A path to flight

NASA Astrophysics Data System (ADS)

Cathey, H. M.

2009-07-01

The National Aeronautics and Space Administration's Balloon Program Office has invested significant time and effort in extensive ground testing of model super pressure balloons. The testing path has been developed as an outgrowth of the results of the super pressure balloon test flight in 2006. Summary results of the June 2006 super pressure test flight from Kiruna, Sweden are presented including the balloon performance and "lessons learned". This balloons flight performance exceeded expectations, but did not fully deploy. The flight was safely terminated by command. The results of this test flight refocused the project's efforts toward additional ground testing and analysis; a path to flight. A series of small 4 m diameter models were made and tested to further explore the deployment and structural capabilities of the balloons and materials. A series of ˜27 m model balloons were successfully tested indoors. These balloons successfully replicated the cleft seen in the Sweden flight, explored the deployment trade space to help characterize better design approaches, and demonstrated an acceptable fix to the deployment issue. Photogrammetry was employed during these ˜27 m model tests to help characterize both the balloon and gore shape evolution under pressurization. A ˜8.5 m ground model was used to explore the design and materials performance. Results of these tests will be presented. A general overview of some of the other project advancements made related to demonstrating the strain arresting nature of the proposed design, materials and analysis work will also be presented. All of this work has prepared a clear path toward a renewed round of test flights. This paper will give an overview of the development approach pursued for this super pressure balloon development. A description of the balloon design, including the modifications made as a result of the lessons learned, is presented. A short deployment test flight of the National Aeronautics and Space Administration's super pressure balloon took place in June 2008. This flight was from Ft. Sumner, New Mexico. Preliminary results of this flight are presented. Future plans for both ground testing and additional test flights are also presented. Goals of the future test flights, which are staged in increments of increasing suspended load and altitude, are presented. This includes the projected balloon volumes, payload capabilities, test flight locations, and proposed flight schedule.

Development and Evaluation of a Performance Modeling Flight Test Approach Based on Quasi Steady-State Maneuvers

NASA Technical Reports Server (NTRS)

Yechout, T. R.; Braman, K. B.

1984-01-01

The development, implementation and flight test evaluation of a performance modeling technique which required a limited amount of quasisteady state flight test data to predict the overall one g performance characteristics of an aircraft. The concept definition phase of the program include development of: (1) the relationship for defining aerodynamic characteristics from quasi steady state maneuvers; (2) a simplified in flight thrust and airflow prediction technique; (3) a flight test maneuvering sequence which efficiently provided definition of baseline aerodynamic and engine characteristics including power effects on lift and drag; and (4) the algorithms necessary for cruise and flight trajectory predictions. Implementation of the concept include design of the overall flight test data flow, definition of instrumentation system and ground test requirements, development and verification of all applicable software and consolidation of the overall requirements in a flight test plan.

Test and Verification Approach for the NASA Constellation Program

NASA Technical Reports Server (NTRS)

Strong, Edward

2008-01-01

This viewgraph presentation is a test and verification approach for the NASA Constellation Program. The contents include: 1) The Vision for Space Exploration: Foundations for Exploration; 2) Constellation Program Fleet of Vehicles; 3) Exploration Roadmap; 4) Constellation Vehicle Approximate Size Comparison; 5) Ares I Elements; 6) Orion Elements; 7) Ares V Elements; 8) Lunar Lander; 9) Map of Constellation content across NASA; 10) CxP T&V Implementation; 11) Challenges in CxP T&V Program; 12) T&V Strategic Emphasis and Key Tenets; 13) CxP T&V Mission & Vision; 14) Constellation Program Organization; 15) Test and Evaluation Organization; 16) CxP Requirements Flowdown; 17) CxP Model Based Systems Engineering Approach; 18) CxP Verification Planning Documents; 19) Environmental Testing; 20) Scope of CxP Verification; 21) CxP Verification - General Process Flow; 22) Avionics and Software Integrated Testing Approach; 23) A-3 Test Stand; 24) Space Power Facility; 25) MEIT and FEIT; 26) Flight Element Integrated Test (FEIT); 27) Multi-Element Integrated Testing (MEIT); 28) Flight Test Driving Principles; and 29) Constellation s Integrated Flight Test Strategy Low Earth Orbit Servicing Capability.

Flight Test of the F/A-18 Active Aeroelastic Wing Airplane

NASA Technical Reports Server (NTRS)

Clarke, Robert; Allen, Michael J.; Dibley, Ryan P.; Gera, Joseph; Hodgkinson, John

2005-01-01

Successful flight-testing of the Active Aeroelastic Wing airplane was completed in March 2005. This program, which started in 1996, was a joint activity sponsored by NASA, Air Force Research Laboratory, and industry contractors. The test program contained two flight test phases conducted in early 2003 and early 2005. During the first phase of flight test, aerodynamic models and load models of the wing control surfaces and wing structure were developed. Design teams built new research control laws for the Active Aeroelastic Wing airplane using these flight-validated models; and throughout the final phase of flight test, these new control laws were demonstrated. The control laws were designed to optimize strategies for moving the wing control surfaces to maximize roll rates in the transonic and supersonic flight regimes. Control surface hinge moments and wing loads were constrained to remain within hydraulic and load limits. This paper describes briefly the flight control system architecture as well as the design approach used by Active Aeroelastic Wing project engineers to develop flight control system gains. Additionally, this paper presents flight test techniques and comparison between flight test results and predictions.

Comparison of Space Shuttle Orbiter low-speed static stability and control derivatives obtained from wind-tunnel and approach and landing flight tests

NASA Technical Reports Server (NTRS)

Freeman, D. C., Jr.; Spencer, B., Jr.

1980-01-01

Tests were conducted in the 8 foot transonic pressure tunnel to obtain wind tunnel data for comparison with static stability and control parameters measured on the space shuttle orbiter approach and landing flight tests. The longitudinal stability, elevon effectiveness, lateral directional stability, and aileron effectiveness derivatives were determined from the wind tunnel data and compared with the flight test results. The comparison covers a range of angles of attack from approximately 2 deg to 10 deg at subsonic Mach numbers of 0.41 to 0.56. In general the wind tunnel results agreed well with the flight test results, indicating the wind tunnel data is applicable to the design of entry vehicles for subsonic speeds over the angle of attack range studied.

On-Line Mu Method for Robust Flutter Prediction in Expanding a Safe Flight Envelope for an Aircraft Model Under Flight Test

NASA Technical Reports Server (NTRS)

Lind, Richard C. (Inventor); Brenner, Martin J.

2001-01-01

A structured singular value (mu) analysis method of computing flutter margins has robust stability of a linear aeroelastic model with uncertainty operators (Delta). Flight data is used to update the uncertainty operators to accurately account for errors in the computed model and the observed range of aircraft dynamics of the aircraft under test caused by time-varying aircraft parameters, nonlinearities, and flight anomalies, such as test nonrepeatability. This mu-based approach computes predict flutter margins that are worst case with respect to the modeling uncertainty for use in determining when the aircraft is approaching a flutter condition and defining an expanded safe flight envelope for the aircraft that is accepted with more confidence than traditional methods that do not update the analysis algorithm with flight data by introducing mu as a flutter margin parameter that presents several advantages over tracking damping trends as a measure of a tendency to instability from available flight data.

Coupled RANS/LES for SOFIA Cavity Acoustic Prediction

NASA Technical Reports Server (NTRS)

Woodruff, Stephen L.

2010-01-01

A fast but accurate approach is described for the determination of the aero-acoustic properties of a large cavity at subsonic flight speeds. This approach employs a detachededdy simulation model in the free-shear layer at the cavity opening and the surrounding boundary layer, but assumes inviscid flow in the cavity and in the far field. The reduced gridding requirements in the cavity, in particular, lead to dramatic improvements in the time required for the computation. Results of these computations are validated against wind-tunnel data. This approach will permit significantly more flight test points to be evaluated computationally in support of the Stratospheric Observatory For Infrared Astronomy flight-test program being carried out at NASA s Dryden Flight Research Center.

Flight Test Results of a GPS-Based Pitot-Static Calibration Method Using Output-Error Optimization for a Light Twin-Engine Airplane

NASA Technical Reports Server (NTRS)

Martos, Borja; Kiszely, Paul; Foster, John V.

2011-01-01

As part of the NASA Aviation Safety Program (AvSP), a novel pitot-static calibration method was developed to allow rapid in-flight calibration for subscale aircraft while flying within confined test areas. This approach uses Global Positioning System (GPS) technology coupled with modern system identification methods that rapidly computes optimal pressure error models over a range of airspeed with defined confidence bounds. This method has been demonstrated in subscale flight tests and has shown small 2- error bounds with significant reduction in test time compared to other methods. The current research was motivated by the desire to further evaluate and develop this method for full-scale aircraft. A goal of this research was to develop an accurate calibration method that enables reductions in test equipment and flight time, thus reducing costs. The approach involved analysis of data acquisition requirements, development of efficient flight patterns, and analysis of pressure error models based on system identification methods. Flight tests were conducted at The University of Tennessee Space Institute (UTSI) utilizing an instrumented Piper Navajo research aircraft. In addition, the UTSI engineering flight simulator was used to investigate test maneuver requirements and handling qualities issues associated with this technique. This paper provides a summary of piloted simulation and flight test results that illustrates the performance and capabilities of the NASA calibration method. Discussion of maneuver requirements and data analysis methods is included as well as recommendations for piloting technique.

Flight test techniques for the X-29A aircraft

NASA Technical Reports Server (NTRS)

Hicks, John W.; Cooper, James M., Jr.; Sefic, Walter J.

1987-01-01

The X-29A advanced technology demonstrator is a single-seat, single-engine aircraft with a forward-swept wing. The aircraft incorporates many advanced technologies being considered for this country's next generation of aircraft. This unusual aircraft configuration, which had never been flown before, required a precise approach to flight envelope expansion. This paper describes the real-time analysis methods and flight test techniques used during the envelope expansion of the x-29A aircraft, including new and innovative approaches.

Design and Testing of a Low Noise Flight Guidance Concept

NASA Technical Reports Server (NTRS)

Williams, David H.; Oseguera-Lohr, Rosa M.; Lewis, Elliot T.

2004-01-01

A flight guidance concept was developed to assist in flying continuous descent approach (CDA) procedures designed to lower the noise under the flight path of jet transport aircraft during arrival operations at an airport. The guidance consists of a trajectory prediction algorithm that was tuned to produce a high-efficiency, low noise flight profile with accompanying autopilot and flight display elements needed by the flight control system and pilot to fly the approach. A key component of the flight guidance was a real-time display of energy error relative to the predicted flight path. The guidance was integrated with the conventional Flight Management System (FMS) guidance of a modern jet transport airplane and tested in a high fidelity flight simulation. A charted arrival procedure, which allowed flying conventional arrivals, CDA arrivals with standard guidance, and CDA arrivals with the new low noise guidance, was developed to assist in the testing and evaluation of the low noise guidance concept. Results of the simulation testing showed the low noise guidance was easy to use by airline pilot test subjects and effective in achieving the desired noise reduction. Noise under the flight path was reduced by at least 2 decibels in Sound Exposure Level (SEL) at distances from about 3 nautical miles out to about 17.5 nautical miles from the runway, with a peak reduction of 8.5 decibels at about 10.5 nautical miles. Fuel consumption was also reduced by about 17% for the LNG conditions compared to baseline runs for the same flight distance. Pilot acceptance and understanding of the guidance was quite high with favorable comments and ratings received from all test subjects.

Synthetic and Enhanced Vision Systems for NextGen (SEVS) Simulation and Flight Test Performance Evaluation

NASA Technical Reports Server (NTRS)

Shelton, Kevin J.; Kramer, Lynda J.; Ellis,Kyle K.; Rehfeld, Sherri A.

2012-01-01

The Synthetic and Enhanced Vision Systems for NextGen (SEVS) simulation and flight tests are jointly sponsored by NASA's Aviation Safety Program, Vehicle Systems Safety Technology project and the Federal Aviation Administration (FAA). The flight tests were conducted by a team of Honeywell, Gulfstream Aerospace Corporation and NASA personnel with the goal of obtaining pilot-in-the-loop test data for flight validation, verification, and demonstration of selected SEVS operational and system-level performance capabilities. Nine test flights (38 flight hours) were conducted over the summer and fall of 2011. The evaluations were flown in Gulfstream.s G450 flight test aircraft outfitted with the SEVS technology under very low visibility instrument meteorological conditions. Evaluation pilots flew 108 approaches in low visibility weather conditions (600 ft to 2400 ft visibility) into various airports from Louisiana to Maine. In-situ flight performance and subjective workload and acceptability data were collected in collaboration with ground simulation studies at LaRC.s Research Flight Deck simulator.

Development and flight test of a helicopter compact, portable, precision landing system concept

NASA Technical Reports Server (NTRS)

Clary, G. R.; Bull, J. S.; Davis, T. J.; Chisholm, J. P.

1984-01-01

An airborne, radar-based, precision approach concept is being developed and flight tested as a part of NASA's Rotorcraft All-Weather Operations Research Program. A transponder-based beacon landing system (BLS) applying state-of-the-art X-band radar technology and digital processing techniques, was built and is being flight tested to demonstrate the concept feasibility. The BLS airborne hardware consists of an add-on microprocessor, installed in conjunction with the aircraft weather/mapping radar, which analyzes the radar beacon receiver returns and determines range, localizer deviation, and glide-slope deviation. The ground station is an inexpensive, portable unit which can be quickly deployed at a landing site. Results from the flight test program show that the BLS concept has a significant potential for providing rotorcraft with low-cost, precision instrument approach capability in remote areas.

Unmanned Aerial Vehicle Flight Test Approval Process and Its Implications: A Methodological Approach to Capture and Evaluate Hidden Costs and Value in the Overall Process

DTIC Science & Technology

2012-03-22

world’s first powered and controlled flying machine. Numerous flight designs and tests were done by scientists, engineers, and flight enthusiasts...conceptual flight and preliminary designs before they could control the craft with three-axis control and the correct airfoil design . These pioneers...analysis support. Although wind tunnel testing can provide data to predict and develop control surface designs , few SUAV operators opt to utilize wind

Reusable Launch Vehicle Technology Program

NASA Technical Reports Server (NTRS)

Freeman, Delma C., Jr.; Talay, Theodore A.; Austin, R. Eugene

1996-01-01

Industry/NASA Reusable Launch Vehicle (RLV) Technology Program efforts are underway to design, test, and develop technologies and concepts for viable commercial launch systems that also satisfy national needs at acceptable recurring costs. Significant progress has been made in understanding the technical challenges of fully reusable launch systems and the accompanying management and operational approaches for achieving a low-cost program. This paper reviews the current status of the Reusable Launch Vehicle Technology Program including the DC-XA, X-33 and X-34 flight systems and associated technology programs. It addresses the specific technologies being tested that address the technical and operability challenges of reusable launch systems including reusable cryogenic propellant tanks, composite structures, thermal protection systems, improved propulsion, and subsystem operability enhancements. The recently concluded DC-XA test program demonstrated some of these technologies in ground and flight tests. Contracts were awarded recently for both the X-33 and X-34 flight demonstrator systems. The Orbital Sciences Corporation X-34 flight test vehicle will demonstrate an air-launched reusable vehicle capable of flight to speeds of Mach 8. The Lockheed-Martin X-33 flight test vehicle will expand the test envelope for critical technologies to flight speeds of Mach 15. A propulsion program to test the X-33 linear aerospike rocket engine using a NASA SR-71 high speed aircraft as a test bed is also discussed. The paper also describes the management and operational approaches that address the challenge of new cost-effective, reusable launch vehicle systems.

A flight-test and simulation evaluation of the longitudinal final approach and landing performance of an automatic system for a light wing loading STOL aircraft

NASA Technical Reports Server (NTRS)

Brown, S. C.; Hardy, G. H.; Hindson, W. S.

1983-01-01

As part of a comprehensive flight-test program of STOL operating systems for the terminal area, an automatic landing system was developed and evaluated for a light wing loading turboprop aircraft. The aircraft utilized an onboard advanced digital avionics system. Flight tests were conducted at a facility that included a STOL runway site with a microwave landing system. Longitudinal flight-test results were presented and compared with available (basically CTOL) criteria. These comparisons were augmented by results from a comprehensive simulation of the controlled aircraft which included representations of navigation errors that were encountered in flight and atmospheric disturbances. Acceptable performance on final approach and at touchdown was achieved by the autoland (automatic landing) system for the moderate winds and turbulence conditions encountered in flight. However, some touchdown performance goals were marginally achieved, and simulation results suggested that difficulties could be encountered in the presence of more extreme atmospheric conditions. Suggestions were made for improving performance under those more extreme conditions.

Acoustic flight tests of rotorcraft noise-abatement approaches using local differential GPS guidance

NASA Technical Reports Server (NTRS)

Chen, Robert T. N.; Hindson, William S.; Mueller, Arnold W.

1995-01-01

This paper presents the test design, instrumentation set-up, data acquisition, and the results of an acoustic flight experiment to study how noise due to blade-vortex interaction (BVI) may be alleviated. The flight experiment was conducted using the NASA/Army Rotorcraft Aircrew Systems Concepts Airborne Laboratory (RASCAL) research helicopter. A Local Differential Global Positioning System (LDGPS) was used for precision navigation and cockpit display guidance. A laser-based rotor state measurement system on board the aircraft was used to measure the main rotor tip-path-plane angle-of-attack. Tests were performed at Crows Landing Airfield in northern California with an array of microphones similar to that used in the standard ICAO/FAA noise certification test. The methodology used in the design of a RASCAL-specific, multi-segment, decelerating approach profile for BVI noise abatement is described, and the flight data pertaining to the flight technical errors and the acoustic data for assessing the noise reduction effectiveness are reported.

Development and Testing of a High Stability Engine Control (HISTEC) System

NASA Technical Reports Server (NTRS)

Orme, John S.; DeLaat, John C.; Southwick, Robert D.; Gallops, George W.; Doane, Paul M.

1998-01-01

Flight tests were recently completed to demonstrate an inlet-distortion-tolerant engine control system. These flight tests were part of NASA's High Stability Engine Control (HISTEC) program. The objective of the HISTEC program was to design, develop, and flight demonstrate an advanced integrated engine control system that uses measurement-based, real-time estimates of inlet airflow distortion to enhance engine stability. With improved stability and tolerance of inlet airflow distortion, future engine designs may benefit from a reduction in design stall-margin requirements and enhanced reliability, with a corresponding increase in performance and decrease in fuel consumption. This paper describes the HISTEC methodology, presents an aircraft test bed description (including HISTEC-specific modifications) and verification and validation ground tests. Additionally, flight test safety considerations, test plan and technique design and approach, and flight operations are addressed. Some illustrative results are presented to demonstrate the type of analysis and results produced from the flight test program.

Dream Chaser ALT-2 Free Flight

NASA Image and Video Library

2017-11-11

Sierra Nevada Corp’s Dream Chaser was lifted by helicopter from the ramp at NASA’s Armstrong Flight Research Center in Edwards, California, before its successful approach and landing flight test on Nov. 11, 2017.

Dream Chaser ALT-2 Free Flight

NASA Image and Video Library

2017-11-11

Sierra Nevada Corp’s Dream Chaser crew prepared for helicopter lift off ramp at NASA’s Armstrong Flight Research Center in California, for its successful approach and landing flight test on Nov. 11, 2017.

A revised approach to the ULDB design

NASA Astrophysics Data System (ADS)

Smith, M.; Cathey, H.

The National Aeronautics and Space Administration Balloon Program has experienced problems in the scaling up of the proposed Ultra Long Duration Balloon. Full deployment of the balloon envelope has been the issue for the larger balloons. There are a number of factors that contribute to this phenomenon. Analytical treatments of the deployment issue are currently underway. It has also been acknowledged that the current fabrication approach using foreshortening is costly, labor intensive, and requires significant handling during production thereby increasing the chances of inducing damage to the envelope. Raven Industries has proposed a new design and fabrication approach that should increase the probability of balloon deployment, does not require foreshortening, will reduce the handling, production labor, and reduce the final balloon cost. This paper will present a description of the logic and approach used to develop this innovation. This development consists of a serial set of steps with decision points that build upon the results of the previous steps. The first steps include limited material development and testing. This will be followed by load testing of bi-axial reinforced cylinders to determine the effect of eliminating the foreshortening. This series of tests have the goal of measuring the strain in the material as it is bi-axially loaded in a condition that closely replicated the application in the full-scale balloon. Constant lobe radius pumpkin shaped test structures will be designed and analyzed. This matrix of model tests, in conjunction with the deployment analyses, will help develop a curve that should clearly present the deployment relationship for this kind of design. This will allow the ``design space'' for this type of balloon to be initially determined. The materials used, analyses, and ground testing results of both cylinders and small pumpkin structures will be presented. Following ground testing, a series of test flights, staged in increments of increasing suspended load and balloon volume, will be conducted. The first small scale test flight has been proposed for early Spring 2004. Results of this test flight of this new design and approach will presented. Two additional domestic test flights from Ft. Sumner, New Mexico, and Palestine, Texas, and one circumglobal test flight from Australia are planned as part of this development. Future plans for both ground testing and test flights will also be presented.

A Revised Approach to the ULDB Design

NASA Technical Reports Server (NTRS)

Smith, Michael; Cathey, H. M., Jr.

2004-01-01

The National Aeronautics and Space Administration Balloon Program has experienced problems in the scaling up of the proposed Ultra Long Duration Balloon. Full deployment of the balloon envelope has been the issue for the larger balloons. There are a number of factors that contribute to this phenomenon. Analytical treatments of the deployment issue are currently underway. It has also been acknowledged that the current fabrication approach using foreshortening is costly, labor intensive, and requires significant handling during production thereby increasing the chances of inducing damage to the envelope. Raven Industries has proposed a new design and fabrication approach that should increase the probability of balloon deployment, does not require foreshortening, will reduce the handling, production labor, and reduce the final balloon cost. This paper will present a description of the logic and approach used to develop this innovation. This development consists of a serial set of steps with decision points that build upon the results of the previous steps. The first steps include limited material development and testing. This will be followed by load testing of bi-axial reinforced cylinders to determine the effect of eliminating the foreshortening. This series of tests have the goal of measuring the strain in the material as it is bi-axially loaded in a condition that closely replicated the application in the full-scale balloon. Constant lobe radius pumpkin shaped test structures will be designed and analyzed. This matrix of model tests, in conjunction with the deployment analyses, will help develop a curve that should clearly present the deployment relationship for this kind of design. This will allow the "design space" for this type of balloon to be initially determined. The materials used, analyses, and ground testing results of both cylinders and small pumpkin structures will be presented. Following ground testing, a series of test flights, staged in increments of increasing suspended load and balloon volume, will be conducted. The first small scale test flight has been proposed for early Spring 2004. Results of this test flight of this new design and approach will presented. Two additional domestic test flights from Ft. Sumner, New Mexico, and Palestine, Texas, and one circumglobal test flight from Australia are planned as part of this development. Future plans for both ground testing and test flights will also be presented.

Effects of Inboard Horizontal Field of View Display Limitations on Pilot Path Control During Total In-Flight Simulator (TIFS) Flight Test

NASA Technical Reports Server (NTRS)

Kramer, Lynda J.; Parrish, Russell V.; Williams, Steven P.; Lavell, Jeffrey S.

1999-01-01

A flight test was conducted aboard Calspan's Total In-Flight Simulator (TIFS) aircraft by researchers within the External Visibility System (XVS) element of the High-Speed Research program. The purpose was to investigate the effects of inboard horizontal field of view (FOV) display limitations on pilot path control and to learn about the TIFS capabilities and limitations for possible use in future XVS flight tests. The TIFS cockpit windows were masked to represent the front XVS display area and the High-Speed Civil Transport side windows, as viewed by the pilot. Masking limited the forward FOV to 40 deg. horizontal and 50 deg. vertical for the basic flight condition, With an increase of 10 deg. horizontal in the inboard direction for the increased FOV flight condition. Two right-hand approach tasks (base-downwind-final) with a left crosswind on final were performed by three pilots using visual flight rules at Niagara Falls Airport. Each of the two tasks had three replicates for both horizontal FOV conditions, resulting in twelve approaches per test subject. Limited objective data showed that an increase of inboard FOV had no effect (deficiences in objective data measurement capabilities were noted). However, subjective results showed that a 50 deg. FOV was preferred over the 40 deg. FOV.

SNC’s Dream Chaser Achieves Successful Free Flight at NASA Armstrong

NASA Image and Video Library

2017-11-17

Sierra Nevada Corporation's Dream Chaser® spacecraft underwent a successful free-flight test on November 11, 2017 at NASA’s Armstrong Flight Research Center, Edwards, California. The test verified and validated the performance of the Dream Chaser in the critical final approach and landing phase of flight, meeting expected models for a future return from the International Space Station. The full-scale Dream Chaser test vehicle was lifted to 12,400 feet altitude by a 234-UT Chinook helicopter, released and flew a pre-planned flight path ending with a successful autonomous landing.

An automated calibration laboratory for flight research instrumentation: Requirements and a proposed design approach

NASA Technical Reports Server (NTRS)

Oneill-Rood, Nora; Glover, Richard D.

1990-01-01

NASA's Dryden Flight Research Facility (Ames-Dryden), operates a diverse fleet of research aircraft which are heavily instrumented to provide both real time data for in-flight monitoring and recorded data for postflight analysis. Ames-Dryden's existing automated calibration (AUTOCAL) laboratory is a computerized facility which tests aircraft sensors to certify accuracy for anticipated harsh flight environments. Recently, a major AUTOCAL lab upgrade was initiated; the goal of this modernization is to enhance productivity and improve configuration management for both software and test data. The new system will have multiple testing stations employing distributed processing linked by a local area network to a centralized database. The baseline requirements for the new AUTOCAL lab and the design approach being taken for its mechanization are described.

KSC-2014-4177

NASA Image and Video Library

2014-10-01

CAPE CANAVERAL, Fla. – The United Launch Alliance Delta IV Heavy rocket for Exploration Flight Test-1 is being lifted to the vertical position at the pad at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. The Delta IV Heavy is being readied to launch Orion on its first flight test. During its first flight test, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Daniel Casper

EFT-1 Delta IV Heavy lift to vertical

NASA Image and Video Library

2014-10-01

This close-up view shows the United Launch Alliance Delta IV Heavy rocket for Exploration Flight Test-1 being raised into the vertical position at the pad at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. The Delta IV Heavy is being readied to launch Orion on its first flight test. During its first flight test, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014.

EFT-1 Delta IV Heavy lift to vertical

NASA Image and Video Library

2014-10-01

The United Launch Alliance Delta IV Heavy rocket for Exploration Flight Test-1 is lifted to the vertical position in the mobile service tower on the pad at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. The Delta IV Heavy is being readied to launch Orion on its first flight test. During its first flight test, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014.

KSC-2014-4176

NASA Image and Video Library

2014-10-01

CAPE CANAVERAL, Fla. – The United Launch Alliance Delta IV Heavy rocket for Exploration Flight Test-1 is being lifted to the vertical position at the pad at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. The Delta IV Heavy is being readied to launch Orion on its first flight test. During its first flight test, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Daniel Casper

EFT-1 Delta IV Heavy lift to vertical

NASA Image and Video Library

2014-10-01

The United Launch Alliance Delta IV Heavy rocket for Exploration Flight Test-1 is being lifted to the vertical position at the pad at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. The Delta IV Heavy is being readied to launch Orion on its first flight test. During its first flight test, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014.

KSC-2014-4170

NASA Image and Video Library

2014-09-30

CAPE CANAVERAL, Fla. – The United Launch Alliance Delta IV Heavy rocket for Exploration Flight Test-1 arrives at the pad at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. The rocket is secured on the Elevated Platform Transporter. The Delta IV Heavy will launch Orion on its first flight test. During its first flight test, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Dimitri Gerondidakis

KSC-2014-4174

NASA Image and Video Library

2014-09-30

CAPE CANAVERAL, Fla. – The United Launch Alliance Delta IV Heavy rocket for Exploration Flight Test-1 has arrived at the pad at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. The rocket is secured on the Elevated Platform Transporter. The Delta IV Heavy will launch Orion on its first flight test. During its first flight test, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Dimitri Gerondidakis

KSC-2014-4171

NASA Image and Video Library

2014-09-30

CAPE CANAVERAL, Fla. – The United Launch Alliance Delta IV Heavy rocket for Exploration Flight Test-1 arrives at the pad at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. The rocket is secured on the Elevated Platform Transporter. The Delta IV Heavy will launch Orion on its first flight test. During its first flight test, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Dimitri Gerondidakis

Flight Test Evaluation of the Airborne Information for Lateral Spacing (AILS) Concept

NASA Technical Reports Server (NTRS)

Abbott, Terence S.

2002-01-01

The Airborne Information for Lateral Spacing (AILS) concept is designed to support independent parallel approach operations to runways spaced as close as 2,500 feet. This report briefly describes the AILS operational concept and the results of a flight test of one implementation of this concept. The focus of this flight test experiment was to validate a prior simulator study, evaluating pilot performance, pilot acceptability, and minimum miss-distances for the rare situation in which an aircraft on one approach intrudes into the path of an aircraft on the other approach. Although the flight data set was not meant to be a statistically valid sample, the trends acquired in flight followed those of the simulator and therefore met the intent of validating the findings from the simulator. Results from this study showed that the design-goal mean miss-distance of 1,200 feet to potential collision situations was surpassed with an actual mean miss-distance of 1,859 feet. Pilot reaction times to the alerting system, which was an operational concern, averaged 0.65 seconds, were well below the design goal reaction time of 2.0 seconds. From the results of both of these tests, it can be concluded that this operational concept, with supporting technology and procedures, may provide an operationally viable means for conducting simultaneous, independent instrument approaches to runways spaced as close as 2500 ft.

Flight test of a propulsion controlled aircraft system on the NASA F-15 airplane

NASA Technical Reports Server (NTRS)

Burcham, Frank W., Jr.; Maine, Trindel A.

1995-01-01

Flight tests of the propulsion controlled aircraft (PCA) system on the NASA F-15 airplane evolved as a result of a long series of simulation and flight tests. Initially, the simulation results were very optimistic. Early flight tests showed that manual throttles-only control was much more difficult than the simulation, and a flight investigation was flown to acquire data to resolve this discrepancy. The PCA system designed and developed by MDA evolved as these discrepancies were found and resolved, requiring redesign of the PCA software and modification of the flight test plan. Small throttle step inputs were flown to provide data for analysis, simulation update, and control logic modification. The PCA flight tests quickly revealed less than desired performance, but the extensive flexibility built into the flight PCA software allowed rapid evaluation of alternate gains, filters, and control logic, and within 2 weeks, the PCA system was functioning well. The initial objective of achieving adequate control for up-and-away flying and approaches was satisfied, and the option to continue to actual landings was achieved. After the PCA landings were accomplished, other PCA features were added, and additional maneuvers beyond those originally planned were flown. The PCA system was used to recover from extreme upset conditions, descend, and make approaches to landing. A heading mode was added, and a single engine plus rudder PCA mode was also added and flown. The PCA flight envelope was expanded far beyond that originally designed for. Guest pilots from the USAF, USN, NASA, and the contractor also flew the PCA system and were favorably impressed.

Digital electronic engine control F-15 overview

NASA Technical Reports Server (NTRS)

Kock, B.

1984-01-01

A flight test evaluation of the digital elctronic engine control (DEEC) system was conducted. An overview of the flight program is presented. The roles of the participating parties, the system, and the flight program objectives are described. The test program approach is discussed, and the engine performance benefits are summarized. A description of the follow-on programs is included.

Dream Chaser ALT-2 Free Flight

NASA Image and Video Library

2017-11-11

After a successful approach and landing flight test on Nov. 11, 2017, Sierra Nevada Corp’s Dream Chaser was towed back to NASA Armstrong Flight Research Center in California, and placed in the former space shuttle hangar.

Differential GPS/inertial navigation approach/landing flight test results

NASA Technical Reports Server (NTRS)

Snyder, Scott; Schipper, Brian; Vallot, Larry; Parker, Nigel; Spitzer, Cary

1992-01-01

In November of 1990 a joint Honeywell/NASA-Langley differential GPS/inertial flight test was conducted at Wallops Island, Virginia. The test objective was to acquire a system performance database and demonstrate automatic landing using an integrated differential GPS/INS (Global Positioning System/inertial navigation system) with barometric and radar altimeters. The flight test effort exceeded program objectives with over 120 landings, 36 of which were fully automatic differential GPS/inertial landings. Flight test results obtained from post-flight data analysis are discussed. These results include characteristics of differential GPS/inertial error, using the Wallops Island Laser Tracker as a reference. Data on the magnitude of the differential corrections and vertical channel performance with and without radar altimeter augmentation are provided.

Flight-test evaluation of civil helicopter terminal approach operations using differential GPS

NASA Technical Reports Server (NTRS)

Edwards, F. G.; Hegarty, D. M.

1989-01-01

A civil code differential Global Positioning System (DGPS) has been developed and flight-tested by the NASA Ames Research Center. The system was used to evaluate the performance of the DGPS for support of helicopter terminal approach operations. The airborne component of the DGPS was installed in a NASA helicopter. The ground-reference component was installed in a mobile van and equipped with a real-time VHF telemetry data link to transmit correction information to the aircraft system. An extensive series of tests was conducted to evaluate the performance of the system for several different configurations of the airborne navigation filter. This paper will describe the systems, the results of the flight tests, and the results of the posttest analysis.

HIFIRE Flight 2 Overview and Status Update 2011

NASA Technical Reports Server (NTRS)

Jackson, Kevin R.; Gruber, Mark R.; Buccellato, Salvatore

2011-01-01

A collaborative international effort, the Hypersonic International Flight Research Experimentation (HIFiRE) Program aims to study basic hypersonic phenomena through flight experimentation. HIFiRE Flight 2 teams the United States Air Force Research Lab (AFRL), NASA, and the Australian Defence Science and Technology Organisation (DSTO). Flight 2 will develop an alternative test technique for acquiring high enthalpy scramjet flight test data, allowing exploration of accelerating hydrocarbon-fueled scramjet performance and dual-to-scram mode transition up to and beyond Mach 8 flight. The generic scramjet flowpath is research quality and the test fuel is a simple surrogate for an endothermically cracked liquid hydrocarbon fuel. HIFiRE Flight 2 will be a first of its kind in contribution to scramjets. The HIFiRE program builds upon the HyShot and HYCAUSE programs and aims to leverage the low-cost flight test technique developed in those programs. It will explore suppressed trajectories of a sounding rocket propelled test article and their utility in studying ramjet-scramjet mode transition and flame extinction limits research. This paper describes the overall scramjet flight test experiment mission goals and objectives, flight test approach and strategy, ground test and analysis summary, development status and project schedule. A successful launch and operation will present to the scramjet community valuable flight test data in addition to a new tool, and vehicle, with which to explore high enthalpy scramjet technologies.

Approach and Landing Tests Film Documentary

NASA Image and Video Library

2018-05-09

Documentary of shuttle Enterprise on the Shuttle Carrier Aircraft (SCA), separating from the SCA in flight, and in free-flight. Footage shows SCA pilots Fitzhugh “Fitz” Fulton and Tom McMurtry heading to the aircraft, and Gordon Fullerton and Fred Haise following a flight in the prototype shuttle. During the nearly one-year-long series of tests, Enterprise was taken aloft on the SCA to study the aerodynamics of the mated vehicles and, in a series of five free flights, tested the glide and landing characteristics of the orbiter prototype.

Space Shuttle stability and control flight test techniques

NASA Technical Reports Server (NTRS)

Cooke, D. R.

1980-01-01

A unique approach for obtaining vehicle aerodynamic characteristics during entry has been developed for the Space Shuttle. This is due to the high cost of Shuttle testing, the need to open constraints for operational flights, and the fact that all flight regimes are flown starting with the first flight. Because of uncertainties associated with predicted aerodynamic coefficients, nine flight conditions have been identified at which control problems could occur. A detailed test plan has been developed for testing at these conditions and is presented. Due to limited testing, precise computer initiated maneuvers are implemented. These maneuvers are designed to optimize the vehicle motion for determining aerodynamic coefficients. Special sensors and atmospheric measurements are required to provide stability and control flight data during an entire entry. The techniques employed in data reduction are proven programs developed and used at NASA/DFRC.

Shuttle avionics software development trials: Tribulations and successes, the backup flight system

NASA Technical Reports Server (NTRS)

Chevers, E. S.

1985-01-01

The development and verification of the Backup Flight System software (BFS) is discussed. The approach taken for the BFS was to develop a very simple and straightforward software program and then test it in every conceivable manner. The result was a program that contained approximately 12,000 full words including ground checkout and the built in test program for the computer. To perform verification, a series of tests was defined using the actual flight type hardware and simulated flight conditions. Then simulated flights were flown and detailed performance analysis was conducted. The intent of most BFS tests was to demonstrate that a stable flightpath could be obtained after engagement from an anomalous initial condition. The extention of the BFS to meet the requirements of the orbital flight test phase is also described.

Approach for Structurally Clearing an Adaptive Compliant Trailing Edge Flap for Flight

NASA Technical Reports Server (NTRS)

Miller, Eric J.; Lokos, William A.; Cruz, Josue; Crampton, Glen; Stephens, Craig A.; Kota, Sridhar; Ervin, Gregory; Flick, Pete

2015-01-01

The Adaptive Compliant Trailing Edge (ACTE) flap was flown on the National Aeronautics and Space Administration (NASA) Gulfstream GIII testbed at the NASA Armstrong Flight Research Center. This smoothly curving flap replaced the existing Fowler flaps creating a seamless control surface. This compliant structure, developed by FlexSys Inc. in partnership with the Air Force Research Laboratory, supported NASA objectives for airframe structural noise reduction, aerodynamic efficiency, and wing weight reduction through gust load alleviation. A thorough structures airworthiness approach was developed to move this project safely to flight. A combination of industry and NASA standard practice require various structural analyses, ground testing, and health monitoring techniques for showing an airworthy structure. This paper provides an overview of compliant structures design, the structural ground testing leading up to flight, and the flight envelope expansion and monitoring strategy. Flight data will be presented, and lessons learned along the way will be highlighted.

Simulation to Flight Test for a UAV Controls Testbed

NASA Technical Reports Server (NTRS)

Motter, Mark A.; Logan, Michael J.; French, Michael L.; Guerreiro, Nelson M.

2006-01-01

The NASA Flying Controls Testbed (FLiC) is a relatively small and inexpensive unmanned aerial vehicle developed specifically to test highly experimental flight control approaches. The most recent version of the FLiC is configured with 16 independent aileron segments, supports the implementation of C-coded experimental controllers, and is capable of fully autonomous flight from takeoff roll to landing, including flight test maneuvers. The test vehicle is basically a modified Army target drone, AN/FQM-117B, developed as part of a collaboration between the Aviation Applied Technology Directorate (AATD) at Fort Eustis, Virginia and NASA Langley Research Center. Several vehicles have been constructed and collectively have flown over 600 successful test flights, including a fully autonomous demonstration at the Association of Unmanned Vehicle Systems International (AUVSI) UAV Demo 2005. Simulations based on wind tunnel data are being used to further develop advanced controllers for implementation and flight test.

Orion Pad Abort 1 Crew Module Inertia Test Approach and Results

NASA Technical Reports Server (NTRS)

Herrera, Claudia; Harding, Adam

2010-01-01

The Flight Loads Laboratory at the Dryden Flight Research Center conducted tests to measure the inertia properties of the Orion Pad Abort 1 (PA-1) Crew Module. These measurements were taken to validate analytical predictions of the inertia properties of the vehicle and assist in reducing uncertainty for derived aero performance results calculated post launch. The first test conducted was to determine the Ixx of the Crew Module. This test approach used a modified torsion pendulum test step up that allowed the suspended Crew Module to rotate about the x axis. The second test used a different approach to measure both the Iyy and Izz properties. This test used a Knife Edge fixture that allowed small rotation of the Crew Module about the y and z axes. Discussions of the techniques and equations used to accomplish each test are presented. Comparisons with the predicted values used for the final flight calculations are made. Problem areas, with explanations and recommendations where available, are addressed. Finally, an evaluation of the value and success of these techniques to measure the moments of inertia of the Crew Module is provided.

Quiet Spike(TradeMark) Build-up Ground Vibration Testing Approach

NASA Technical Reports Server (NTRS)

Spivey, Natalie D.; Herrera, Claudia Y.; Truax, Roger; Pak, Chan-gi; Freund, Donald

2007-01-01

Flight tests of the Gulfstream Aerospace Corporation s Quiet Spike(TradeMark) hardware were recently completed on the National Aeronautics and Space Administration Dryden Flight Research Center F-15B airplane. NASA Dryden uses a modified F-15B (836) airplane as a testbed aircraft to cost-effectively fly flight research experiments that are typically mounted underneath the airplane, along the fuselage centerline. For the Quiet Spike(TradeMark) experiment, instead of a centerline mounting, a forward-pointing boom was attached to the radar bulkhead of the airplane. The Quiet Spike(TradeMark) experiment is a stepping-stone to airframe structural morphing technologies designed to mitigate the sonic-boom strength of business jets flying over land. Prior to flying the Quiet Spike(TradeMark) experiment on the F-15B airplane several ground vibration tests were required to understand the Quiet Spike(TradeMark) modal characteristics and coupling effects with the F-15B airplane. Because of flight hardware availability and compressed schedule requirements, a "traditional" ground vibration test of the mated F-15B Quiet Spike(TradeMark) ready-for-flight configuration did not leave sufficient time available for the finite element model update and flutter analyses before flight-testing. Therefore, a "nontraditional" ground vibration testing approach was taken. This report provides an overview of each phase of the "nontraditional" ground vibration testing completed for the Quiet Spike(TradeMark) project.

Flight Test Evaluation of the ATD-1 Interval Management Application

NASA Technical Reports Server (NTRS)

Swieringa, Kurt A.; Wilson, Sara R.; Baxley, Brian T.; Roper, Roy D.; Abbott, Terence S.; Levitt, Ian; Scharl, Julien

2017-01-01

Interval Management (IM) is a concept designed to be used by air traffic controllers and flight crews to more efficiently and precisely manage inter-aircraft spacing. Both government and industry have been working together to develop the IM concept and standards for both ground automation and supporting avionics. NASA contracted with Boeing, Honeywell, and United Airlines to build and flight test an avionics prototype based on NASA's spacing algorithm and conduct a flight test. The flight test investigated four different types of IM operations over the course of nineteen days, and included en route, arrival, and final approach phases of flight. This paper examines the spacing accuracy achieved during the flight test and the rate of speed commands provided to the flight crew. Many of the time-based IM operations met or exceeded the operational design goals set out in the standards for the maintain operations and a subset of the achieve operations. Those operations which did not meet the goals were due to issues that are identified and will be further analyzed.

EFT-1 Delta IV Heavy lift to vertical

NASA Image and Video Library

2014-10-01

The United Launch Alliance Delta IV Heavy rocket for Exploration Flight Test-1 is being lifted to the vertical position in the mobile service tower on the pad at the pad at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. The Delta IV Heavy is being readied to launch Orion on its first flight test. During its first flight test, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014.

KSC-2014-4178

NASA Image and Video Library

2014-10-01

CAPE CANAVERAL, Fla. – This close-up view shows the United Launch Alliance Delta IV Heavy rocket for Exploration Flight Test-1 being raised into the vertical position at the pad at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. The Delta IV Heavy is being readied to launch Orion on its first flight test. During its first flight test, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Daniel Casper

KSC-2014-4179

NASA Image and Video Library

2014-10-01

CAPE CANAVERAL, Fla. – This close-up view shows the United Launch Alliance Delta IV Heavy rocket for Exploration Flight Test-1 being raised into the vertical position at the pad at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. The Delta IV Heavy is being readied to launch Orion on its first flight test. During its first flight test, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Daniel Casper

KSC-2014-4184

NASA Image and Video Library

2014-10-01

CAPE CANAVERAL, Fla. – The United Launch Alliance Delta IV Heavy rocket for Exploration Flight Test-1 is lifted to the vertical position in the mobile service tower on the pad at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. The Delta IV Heavy is being readied to launch Orion on its first flight test. During its first flight test, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Daniel Casper

KSC-2014-4181

NASA Image and Video Library

2014-10-01

CAPE CANAVERAL, Fla. – The United Launch Alliance Delta IV Heavy rocket for Exploration Flight Test-1 is being lifted to the vertical position in the mobile service tower on the pad at the pad at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. The Delta IV Heavy is being readied to launch Orion on its first flight test. During its first flight test, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Daniel Casper

KSC-2014-4180

NASA Image and Video Library

2014-10-01

CAPE CANAVERAL, Fla. – The United Launch Alliance Delta IV Heavy rocket for Exploration Flight Test-1 is lifted to the vertical position in the mobile service tower on the pad at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. The Delta IV Heavy is being readied to launch Orion on its first flight test. During its first flight test, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Daniel Casper

EFT-1 Delta IV Heavy lift to vertical

NASA Image and Video Library

2014-10-01

United Launch Alliance, or ULA, workers monitor the progress as the ULA Delta IV Heavy rocket for Exploration Flight Test-1 is lifted to the vertical position in the mobile service tower on the pad at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. The Delta IV Heavy is being readied to launch Orion on its first flight test. During its first flight test, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014.

KSC-2014-4175

NASA Image and Video Library

2014-09-30

CAPE CANAVERAL, Fla. – Launch pad lights give off a golden glow at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida, as the United Launch Alliance Delta IV Heavy rocket for Exploration Flight Test-1 arrives. The rocket is secured on the Elevated Platform Transporter. The Delta IV Heavy will launch Orion on its first flight test. During its first flight test, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Dimitri Gerondidakis

KSC-2014-4172

NASA Image and Video Library

2014-09-30

CAPE CANAVERAL, Fla. – Launch pad lights give off a golden glow at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida, as the United Launch Alliance Delta IV Heavy rocket for Exploration Flight Test-1 arrives. The rocket is secured on the Elevated Platform Transporter. The Delta IV Heavy will launch Orion on its first flight test. During its first flight test, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Dimitri Gerondidakis

KSC-07pd0913

NASA Image and Video Library

2007-04-17

KENNEDY SPACE CENTER, FLA. -- The Starfighter F-104 approaches the runway at the KSC Shuttle Landing Facility for a landing after its test flight. The aircraft is taking part in a series of pathfinder test missions from the space shuttle runway. Two flights will generate test data to validate sonic boom assumptions about the potential impacts of suborbital and orbital commercial spaceflight from the facility. NASA is assessing the environmental impact of such flights. Starfighters Inc. of Clearwater, Fla., will perform the flights to help in assessing suborbital space launch trajectories from the runway and paving the way for future commercial space tourism and research flights from the facility. Photo credit: NASA/Kim Shiflett

Vista/F-16 Multi-Axis Thrust Vectoring (MATV) control law design and evaluation

NASA Technical Reports Server (NTRS)

Zwerneman, W. D.; Eller, B. G.

1994-01-01

For the Multi-Axis Thrust Vectoring (MATV) program, a new control law was developed using multi-axis thrust vectoring to augment the aircraft's aerodynamic control power to provide maneuverability above the normal F-16 angle of attack limit. The control law architecture was developed using Lockheed Fort Worth's offline and piloted simulation capabilities. The final flight control laws were used in flight test to demonstrate tactical benefits gained by using thrust vectoring in air-to-air combat. Differences between the simulator aerodynamics data base and the actual aircraft aerodynamics led to significantly different lateral-directional flying qualities during the flight test program than those identified during piloted simulation. A 'dial-a-gain' flight test control law update was performed in the middle of the flight test program. This approach allowed for inflight optimization of the aircraft's flying qualities. While this approach is not preferred over updating the simulator aerodynamic data base and then updating the control laws, the final selected gain set did provide adequate lateral-directional flying qualities over the MATV flight envelope. The resulting handling qualities and the departure resistance of the aircraft allowed the 422nd_squadron pilots to focus entirely on evaluating the aircraft's tactical utility.

HUD Guidance for the ASKA Experimental STOL Aircraft using Radar Position Information

NASA Technical Reports Server (NTRS)

Yazawa, Kenji; Terui, Yushi; Hardy, Gordon H.

1992-01-01

The paper describes a high performance HUD guidance system installed on the experimental powered-lift STOL aircraft Aska. Since the maiden flight in October 1985, the HUD system has been used in all the flight tests. The HUD has an accurate flight path symbol generated by inertial velocity from the IRS which is updated by up-linked precision radar position data. The flight path symbol is very useful for precise approach and flare control for Aska which has large ground effects. A synthetic runway is also presented, which is conformal with the real runway, using the position data from the ground tracking radar system. Under instrument meteorological conditions, the pilot can approach and land using the HUD synthetic runway as well as in visual meteorological conditions. The HUD system proved to be a valuable aid to the pilot for all the Aska flight tests. A NASA Ames Research Center test pilot demonstrated touch down accuracy of less than 8 meters (peak to peak) for a series of three landings.

The NASA Hyper-X Program

NASA Technical Reports Server (NTRS)

Freeman, Delman C., Jr.; Reubush, Daivd E.; McClinton, Charles R.; Rausch, Vincent L.; Crawford, J. Larry

1997-01-01

This paper provides an overview of NASA's Hyper-X Program; a focused hypersonic technology effort designed to move hypersonic, airbreathing vehicle technology from the laboratory environment to the flight environment. This paper presents an overview of the flight test program, research objectives, approach, schedule and status. Substantial experimental database and concept validation have been completed. The program is currently concentrating on the first, Mach 7, vehicle development, verification and validation in preparation for wind-tunnel testing in 1998 and flight testing in 1999. Parallel to this effort the Mach 5 and 10 vehicle designs are being finalized. Detailed analytical and experimental evaluation of the Mach 7 vehicle at the flight conditions is nearing completion, and will provide a database for validation of design methods once flight test data are available.

Development and Flight Test of an Augmented Thrust-Only Flight Control System on an MD-11 Transport Airplane

NASA Technical Reports Server (NTRS)

Burcham, Frank W., Jr.; Maine, Trindel A.; Burken, John J.; Pappas, Drew

1996-01-01

An emergency flight control system using only engine thrust, called Propulsion-Controlled Aircraft (PCA), has been developed and flight tested on an MD-11 airplane. In this thrust-only control system, pilot flight path and track commands and aircraft feedback parameters are used to control the throttles. The PCA system was installed on the MD-11 airplane using software modifications to existing computers. Flight test results show that the PCA system can be used to fly to an airport and safely land a transport airplane with an inoperative flight control system. In up-and-away operation, the PCA system served as an acceptable autopilot capable of extended flight over a range of speeds and altitudes. The PCA approaches, go-arounds, and three landings without the use of any non-nal flight controls have been demonstrated, including instrument landing system-coupled hands-off landings. The PCA operation was used to recover from an upset condition. In addition, PCA was tested at altitude with all three hydraulic systems turned off. This paper reviews the principles of throttles-only flight control; describes the MD-11 airplane and systems; and discusses PCA system development, operation, flight testing, and pilot comments.

Autonomous Flying Controls Testbed

NASA Technical Reports Server (NTRS)

Motter, Mark A.

2005-01-01

The Flying Controls Testbed (FLiC) is a relatively small and inexpensive unmanned aerial vehicle developed specifically to test highly experimental flight control approaches. The most recent version of the FLiC is configured with 16 independent aileron segments, supports the implementation of C-coded experimental controllers, and is capable of fully autonomous flight from takeoff roll to landing, including flight test maneuvers. The test vehicle is basically a modified Army target drone, AN/FQM-117B, developed as part of a collaboration between the Aviation Applied Technology Directorate (AATD) at Fort Eustis,Virginia and NASA Langley Research Center. Several vehicles have been constructed and collectively have flown over 600 successful test flights.

Flight Test Results of an Angle of Attack and Angle of Sideslip Calibration Method Using Output-Error Optimization

NASA Technical Reports Server (NTRS)

Siu, Marie-Michele; Martos, Borja; Foster, John V.

2013-01-01

As part of a joint partnership between the NASA Aviation Safety Program (AvSP) and the University of Tennessee Space Institute (UTSI), research on advanced air data calibration methods has been in progress. This research was initiated to expand a novel pitot-static calibration method that was developed to allow rapid in-flight calibration for the NASA Airborne Subscale Transport Aircraft Research (AirSTAR) facility. This approach uses Global Positioning System (GPS) technology coupled with modern system identification methods that rapidly computes optimal pressure error models over a range of airspeed with defined confidence bounds. Subscale flight tests demonstrated small 2-s error bounds with significant reduction in test time compared to other methods. Recent UTSI full scale flight tests have shown airspeed calibrations with the same accuracy or better as the Federal Aviation Administration (FAA) accepted GPS 'four-leg' method in a smaller test area and in less time. The current research was motivated by the desire to extend this method for inflight calibration of angle of attack (AOA) and angle of sideslip (AOS) flow vanes. An instrumented Piper Saratoga research aircraft from the UTSI was used to collect the flight test data and evaluate flight test maneuvers. Results showed that the output-error approach produces good results for flow vane calibration. In addition, maneuvers for pitot-static and flow vane calibration can be integrated to enable simultaneous and efficient testing of each system.

Dream Chaser ALT-2 Free Flight

NASA Image and Video Library

2017-11-11

Sierra Nevada Corp’s Dream Chaser is released for a landing on Edwards Air Force Base runway after departing a ramp at NASA’s Armstrong Flight Research Center in California, for its successful approach and landing flight test on Nov. 11, 2017.

Flight test investigation of the vortex wake characteristics behind a Boeing 727 during two-segment and normal ILS approaches (A joint NASA/FAA report)

NASA Technical Reports Server (NTRS)

Barber, M. R.; Kurkowski, R. L.; Garodz, L. J.; Robinson, G. H.; Smith, H. J.; Jacobsen, R. A.; Stinnett, G. W., Jr.; Mcmurtry, T. C.; Tymczyszyn, J. J.; Devereaux, R. L.

1975-01-01

Flight tests were performed to evaluate the vortex wake characteristics of a Boeing 727 aircraft during conventional and two-segment instrument landing approaches. Smoke generators were used for vortex marking. The vortex was intentionally intercepted by a Lear Jet and a Piper Comanche aircraft. The vortex location during landing approach was measured using a system of phototheodolites. The tests showed that at a given separation distance there are no readily apparent differences in the upsets resulting from deliberate vortex encounters during the two types of approaches. The effect of the aircraft configuration on the extent and severity of the vortices is discussed.

Asymmetry of flight and escape turning responses in horses.

PubMed

Austin, N P; Rogers, L J

2007-09-01

We investigated whether horses display greater reactivity to a novel stimulus presented in the left compared to the right monocular visual field, and whether a population bias exists for escape turning when the same stimulus was presented binocularly. Domestic horses (N=30) were tested on three occasions by a person opening an umbrella five metres away and then approaching. The distance each horse moved away before stopping was measured. Distance was greatest for approach on the left side, indicating right hemisphere control of flight behaviour, and thus followed the same pattern found previously in other species. When order of monocular presentation was considered, an asymmetry was detected. Horses tested initially on the left side exhibited greater reactivity for left approach, whereas horses tested on the right side first displayed no side difference in reactivity. Perhaps left hemisphere inhibition of flight response allowed horses to learn that the stimulus posed no threat and this information was transferred to the right hemisphere. No population bias existed for the direction of escape turning, but horses that turned to the right when approached from the front were found to exhibit longer flight distances than those that turned to the left.

KSC-2014-4182

NASA Image and Video Library

2014-10-01

CAPE CANAVERAL, Fla. – United Launch Alliance, or ULA, workers monitor the progress as the ULA Delta IV Heavy rocket for Exploration Flight Test-1 is lifted to the vertical position in the mobile service tower on the pad at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. The Delta IV Heavy is being readied to launch Orion on its first flight test. During its first flight test, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Daniel Casper

KSC-2014-4183

NASA Image and Video Library

2014-10-01

CAPE CANAVERAL, Fla. – United Launch Alliance, or ULA, workers monitor the progress as the ULA Delta IV Heavy rocket for Exploration Flight Test-1 is lifted to the vertical position in the mobile service tower on the pad at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. The Delta IV Heavy is being readied to launch Orion on its first flight test. During its first flight test, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Daniel Casper

KSC-2014-4173

NASA Image and Video Library

2014-09-30

CAPE CANAVERAL, Fla. – The United Launch Alliance, or ULA, Delta IV Heavy rocket for Exploration Flight Test-1 continues its trek to the pad at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. ULA technicians help guide the transporter to the pad. The rocket is secured on the Elevated Platform Transporter. The Delta IV Heavy will launch Orion on its first flight test. During its first flight test, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Dimitri Gerondidakis

Hyper-X: Flight Validation of Hypersonic Airbreathing Technology

NASA Technical Reports Server (NTRS)

Rausch, Vincent L.; McClinton, Charles R.; Crawford, J. Larry

1997-01-01

This paper provides an overview of NASA's focused hypersonic technology program, i.e. the Hyper-X program. This program is designed to move hypersonic, air breathing vehicle technology from the laboratory environment to the flight environment, the last stage preceding prototype development. This paper presents some history leading to the flight test program, research objectives, approach, schedule and status. Substantial experimental data base and concept validation have been completed. The program is concentrating on Mach 7 vehicle development, verification and validation in preparation for wind tunnel testing in 1998 and flight testing in 1999. It is also concentrating on finalization of the Mach 5 and 10 vehicle designs. Detailed evaluation of the Mach 7 vehicle at the flight conditions is nearing completion, and will provide a data base for validation of design methods once flight test data are available.

A parachute system for upper atmospheric studies

NASA Technical Reports Server (NTRS)

Maksimovic, V. M.

1979-01-01

The Goddard Space Flight Center's Sounding Rocket Division successfully flight tested a high altitude, low velocity, 63.5 foot cross parachute system. The system was developed to provide a platform for atmospheric studies at altitudes higher than those attainable with balloons. This paper represents the approach taken to determine the necessary conditions for a successful apogee deployment of the parachute. The test flight deployed the parachute system at an apogee altitude of 61 kilometers. Post-flight results of rocket and parachute performance are compared to the preflight analyses.

Flight Test Experiment Design for Characterizing Stability and Control of Hypersonic Vehicles

NASA Technical Reports Server (NTRS)

Morelli, Eugene A.

2008-01-01

A maneuver design method that is particularly well-suited for determining the stability and control characteristics of hypersonic vehicles is described in detail. Analytical properties of the maneuver design are explained. The importance of these analytical properties for maximizing information content in flight data is discussed, along with practical implementation issues. Results from flight tests of the X-43A hypersonic research vehicle (also called Hyper-X) are used to demonstrate the excellent modeling results obtained using this maneuver design approach. A detailed design procedure for generating the maneuvers is given to allow application to other flight test programs.

Development of Enhanced Avionics Flight Hardware Selection Process

NASA Technical Reports Server (NTRS)

Smith, K.; Watson, G. L.

2003-01-01

The primary objective of this research was to determine the processes and feasibility of using commercial off-the-shelf PC104 hardware for flight applications. This would lead to a faster, better, and cheaper approach to low-budget programs as opposed to the design, procurement. and fabrication of space flight hardware. This effort will provide experimental evaluation with results of flight environmental testing. Also, a method and/or suggestion used to bring test hardware up to flight standards will be given. Several microgravity programs, such as the Equiaxed Dendritic Solidification Experiment, Self-Diffusion in Liquid Elements, and various other programs, are interested in PC104 environmental testing to establish the limits of this technology.

A Worst-Case Approach for On-Line Flutter Prediction

NASA Technical Reports Server (NTRS)

Lind, Rick C.; Brenner, Martin J.

1998-01-01

Worst-case flutter margins may be computed for a linear model with respect to a set of uncertainty operators using the structured singular value. This paper considers an on-line implementation to compute these robust margins in a flight test program. Uncertainty descriptions are updated at test points to account for unmodeled time-varying dynamics of the airplane by ensuring the robust model is not invalidated by measured flight data. Robust margins computed with respect to this uncertainty remain conservative to the changing dynamics throughout the flight. A simulation clearly demonstrates this method can improve the efficiency of flight testing by accurately predicting the flutter margin to improve safety while reducing the necessary flight time.

Flight testing a propulsion-controlled aircraft emergency flight control system on an F-15 airplane

NASA Technical Reports Server (NTRS)

Burcham, F. W., Jr.; Burken, John; Maine, Trindel A.

1994-01-01

Flight tests of a propulsion-controlled aircraft (PCA) system on an F-15 airplane have been conducted at the NASA Dryden Flight Research Center. The airplane was flown with all flight control surfaces locked both in the manual throttles-only mode and in an augmented system mode. In the latter mode, pilot thumbwheel commands and aircraft feedback parameters were used to position the throttles. Flight evaluation results showed that the PCA system can be used to land an airplane that has suffered a major flight control system failure safely. The PCA system was used to recover the F-15 airplane from a severe upset condition, descend, and land. Pilots from NASA, U.S. Air Force, U.S. Navy, and McDonnell Douglas Aerospace evaluated the PCA system and were favorably impressed with its capability. Manual throttles-only approaches were unsuccessful. This paper describes the PCA system operation and testing. It also presents flight test results and pilot comments.

Flight testing and simulation of an F-15 airplane using throttles for flight control

NASA Technical Reports Server (NTRS)

Burcham, Frank W., Jr.; Maine, Trindel; Wolf, Thomas

1992-01-01

Flight tests and simulation studies using the throttles of an F-15 airplane for emergency flight control have been conducted at the NASA Dryden Flight Research Facility. The airplane and the simulation are capable of extended up-and-away flight, using only throttles for flight path control. Initial simulation results showed that runway landings using manual throttles-only control were difficult, but possible with practice. Manual approaches flown in the airplane were much more difficult, indicating a significant discrepancy between flight and simulation. Analysis of flight data and development of improved simulation models that resolve the discrepancy are discussed. An augmented throttle-only control system that controls bank angle and flight path with appropriate feedback parameters has also been developed, evaluated in simulations, and is planned for flight in the F-15.

An automated calibration laboratory - Requirements and design approach

NASA Technical Reports Server (NTRS)

O'Neil-Rood, Nora; Glover, Richard D.

1990-01-01

NASA's Dryden Flight Research Facility (Ames-Dryden), operates a diverse fleet of research aircraft which are heavily instrumented to provide both real time data for in-flight monitoring and recorded data for postflight analysis. Ames-Dryden's existing automated calibration (AUTOCAL) laboratory is a computerized facility which tests aircraft sensors to certify accuracy for anticipated harsh flight environments. Recently, a major AUTOCAL lab upgrade was initiated; the goal of this modernization is to enhance productivity and improve configuration management for both software and test data. The new system will have multiple testing stations employing distributed processing linked by a local area network to a centralized database. The baseline requirements for the new AUTOCAL lab and the design approach being taken for its mechanization are described.

Investigation of air transportation technology at Massachusetts Institute of Technology, 1985

NASA Technical Reports Server (NTRS)

Simpson, Robert W.

1987-01-01

Two areas of research are discussed, an investigation into runway approach flying with Loran C and a series of research topics in the development of experimental validation of methodologies to support aircraft icing analysis. Flight tests with the Loran C led to the conclusion that it is a suitable system for non-precision approaches, and that time-difference corrections made every eight weeks in the instrument approach plates will produce acceptable errors. In the area of aircraft icing analysis, wind tunnel and flight test results are discussed.

Ultraviolet sensor as integrity monitor for enhanced flight vision system (EFVS) approaches to Cat II RVR conditions

NASA Astrophysics Data System (ADS)

McKinley, John B.; Pierson, Roger; Ertem, M. C.; Krone, Norris J., Jr.; Cramer, James A.

2008-04-01

Flight tests were conducted at Greenbrier Valley Airport (KLWB) and Easton Municipal Airport / Newnam Field (KESN) in a Cessna 402B aircraft using a head-up display (HUD) and a Norris Electro Optical Systems Corporation (NEOC) developmental ultraviolet (UV) sensor. These flights were sponsored by NEOC under a Federal Aviation Administration program, and the ultraviolet concepts, technology, system mechanization, and hardware for landing during low visibility landing conditions have been patented by NEOC. Imagery from the UV sensor, HUD guidance cues, and out-the-window videos were separately recorded at the engineering workstation for each approach. Inertial flight path data were also recorded. Various configurations of portable UV emitters were positioned along the runway edge and threshold. The UV imagery of the runway outline was displayed on the HUD along with guidance generated from the mission computer. Enhanced Flight Vision System (EFVS) approaches with the UV sensor were conducted from the initial approach fix to the ILS decision height in both VMC and IMC. Although the availability of low visibility conditions during the flight test period was limited, results from previous fog range testing concluded that UV EFVS has the performance capability to penetrate CAT II runway visual range obscuration. Furthermore, independent analysis has shown that existing runway light emit sufficient UV radiation without the need for augmentation other than lens replacement with UV transmissive quartz lenses. Consequently, UV sensors should qualify as conforming to FAA requirements for EFVS approaches. Combined with Synthetic Vision System (SVS), UV EFVS would function as both a precision landing aid, as well as an integrity monitor for the GPS and SVS database.

Flight Qualification of the NASA's Super Pressure Balloon

NASA Astrophysics Data System (ADS)

Cathey, Henry; Said, Magdi; Fairbrother, Debora

Designs of new balloons to support space science require a number of actual flights under various flight conditions to qualify them to as standard balloon flight offerings to the science community. Development of the new Super Pressure Balloon for the National Aeronautics and Space Administration’s Balloon Program Office has entailed employing new design, analysis, and production techniques to advance the state of the art. Some of these advances have been evolutionary steps and some have been revolutionary steps requiring a maturing understanding of the materials, designs, and manufacturing approaches. The NASA Super Pressure Balloon development end goal is to produce a flight vehicle that is qualified to carry a ton of science instrumentation, at an altitude greater than 33 km while maintaining a near constant pressure altitude for extended periods of up to 100 days, and at any latitude on the globe. The NASA’s Balloon Program Office has pursued this development in a carefully executed incremental approach by gradually increasing payload carrying capability and increasing balloon volume to reach these end goal. A very successful test flight of a ~200,700 m3 balloon was launch in late 2008 from Antarctica. This balloon flew for over 54 days at a constant altitude and circled the Antarctic continent almost three times. A larger balloon was flown from Antarctica in early 2011. This ~422,400 m3 flew at a constant altitude for 22 days making one circuit around Antarctica. Although the performance was nominal, the flight was terminated via command to recover high valued assets from the payload. The balloon designed to reach the program goals is a ~532,200 m3 pumpkin shaped Super Pressure Balloon. A test flight of this balloon was launched from the Swedish Space Corporation’s Esrange Balloon Launch Facilities near Kiruna, Sweden on 14 August, 2012. This flight was another success for this development program. Valuable information was gained from this short test flight by successfully demonstrated balloon vehicle performance, obtained a large amount of videos, measured balloon differential pressure, obtained temperature and altitude data, assessed structure strength through pressurization, and demonstrated the balloon vehicles altitude stability. This flight was the first of several to qualify this design for the science community. Results of the most recent flights will be presented. Some of the related material characterization testing which is vital to the balloon design development for the balloon will also be presented. Additionally, this paper will provide a current overview of the development and qualification approach pursued for the NASA’s Super Pressure Balloon. Future plans and goals of future test flights will also be presented. This will include the projected balloon volumes, payload capabilities, test flight locations, and proposed flight schedule.

NASA Synthetic Vision EGE Flight Test

NASA Technical Reports Server (NTRS)

Prinzel, Lawrence J.; Kramer, Lynda J.; Comstock, J. Raymond; Bailey, Randall E.; Hughes, Monica F.; Parrish, Russell V.

2002-01-01

NASA Langley Research Center conducted flight tests at the Eagle County, Colorado airport to evaluate synthetic vision concepts. Three display concepts (size 'A' head-down, size 'X' head-down, and head-up displays) and two texture concepts (photo, generic) were assessed for situation awareness and flight technical error / performance while making approaches to Runway 25 and Runway 07 and simulated engine-out Cottonwood 2 and KREMM departures. The results of the study confirm the retrofit capability of the HUD and Size 'A' SVS concepts to significantly improve situation awareness and performance over current EFIS glass and non-glass instruments for difficult approaches in terrain-challenged environments.

Orion Pad Abort 1 Crew Module Mass Properties Test Approach and Results

NASA Technical Reports Server (NTRS)

Herrera, Claudia; Harding, Adam

2012-01-01

The Flight Loads Laboratory at the Dryden Flight Research Center conducted tests to measure the inertia properties of the Orion Pad Abort 1 (PA-1) Crew Module (CM). These measurements were taken to validate analytical predictions of the inertia properties of the vehicle and assist in reducing uncertainty for derived aero performance coefficients to be calculated post-launch. The first test conducted was to determine the Ixx of the Crew Module. This test approach used a modified torsion pendulum test setup that allowed the suspended Crew Module to rotate about the x axis. The second test used a different approach to measure both the Iyy and Izz properties. This test used a Knife Edge fixture that allowed small rotation of the Crew Module about the y and z axes. Discussions of the techniques and equations used to accomplish each test are presented. Comparisons with the predicted values used for the final flight calculations are made. Problem areas, with explanations and recommendations where available, are addressed. Finally, an evaluation of the value and success of these techniques to measure the moments of inertia of the Crew Module is provided.

Important factors in the maximum likelihood analysis of flight test maneuvers

NASA Technical Reports Server (NTRS)

Iliff, K. W.; Maine, R. E.; Montgomery, T. D.

1979-01-01

The information presented is based on the experience in the past 12 years at the NASA Dryden Flight Research Center of estimating stability and control derivatives from over 3500 maneuvers from 32 aircraft. The overall approach to the analysis of dynamic flight test data is outlined. General requirements for data and instrumentation are discussed and several examples of the types of problems that may be encountered are presented.

Model-Based GN and C Simulation and Flight Software Development for Orion Missions beyond LEO

NASA Technical Reports Server (NTRS)

Odegard, Ryan; Milenkovic, Zoran; Henry, Joel; Buttacoli, Michael

2014-01-01

For Orion missions beyond low Earth orbit (LEO), the Guidance, Navigation, and Control (GN&C) system is being developed using a model-based approach for simulation and flight software. Lessons learned from the development of GN&C algorithms and flight software for the Orion Exploration Flight Test One (EFT-1) vehicle have been applied to the development of further capabilities for Orion GN&C beyond EFT-1. Continuing the use of a Model-Based Development (MBD) approach with the Matlab®/Simulink® tool suite, the process for GN&C development and analysis has been largely improved. Furthermore, a model-based simulation environment in Simulink, rather than an external C-based simulation, greatly eases the process for development of flight algorithms. The benefits seen by employing lessons learned from EFT-1 are described, as well as the approach for implementing additional MBD techniques. Also detailed are the key enablers for improvements to the MBD process, including enhanced configuration management techniques for model-based software systems, automated code and artifact generation, and automated testing and integration.

Design of Quiet Rotorcraft Approach Trajectories: Verification Phase

NASA Technical Reports Server (NTRS)

Padula, Sharon L.

2010-01-01

Flight testing that is planned for October 2010 will provide an opportunity to evaluate rotorcraft trajectory optimization techniques. The flight test will involve a fully instrumented MD-902 helicopter, which will be flown over an array of microphones. In this work, the helicopter approach trajectory is optimized via a multiobjective genetic algorithm to improve community noise, passenger comfort, and pilot acceptance. Previously developed optimization strategies are modified to accommodate new helicopter data and to increase pilot acceptance. This paper describes the MD-902 trajectory optimization plus general optimization strategies and modifications that are needed to reduce the uncertainty in noise predictions. The constraints that are imposed by the flight test conditions and characteristics of the MD-902 helicopter limit the testing possibilities. However, the insights that will be gained through this research will prove highly valuable.

Predicting flight delay based on multiple linear regression

NASA Astrophysics Data System (ADS)

Ding, Yi

2017-08-01

Delay of flight has been regarded as one of the toughest difficulties in aviation control. How to establish an effective model to handle the delay prediction problem is a significant work. To solve the problem that the flight delay is difficult to predict, this study proposes a method to model the arriving flights and a multiple linear regression algorithm to predict delay, comparing with Naive-Bayes and C4.5 approach. Experiments based on a realistic dataset of domestic airports show that the accuracy of the proposed model approximates 80%, which is further improved than the Naive-Bayes and C4.5 approach approaches. The result testing shows that this method is convenient for calculation, and also can predict the flight delays effectively. It can provide decision basis for airport authorities.

Free Enterprise: Contributions of the Approach and Landing Test (ALT) Program to the Development of the Space Shuttle Orbiter

NASA Technical Reports Server (NTRS)

Merlin, Peter W.

2006-01-01

The space shuttle orbiter was the first spacecraft designed with the aerodynamic characteristics and in-atmosphere handling qualities of a conventional airplane. In order to evaluate the orbiter's flight control systems and subsonic handling characteristics, a series of flight tests were undertaken at NASA Dryden Flight Research Center in 1977. A modified Boeing 747 Shuttle Carrier Aircraft carried the Enterprise, a prototype orbiter, during eight captive tests to determine how well the two vehicles flew together and to test some of the orbiter s systems. The free-flight phase of the ALT program allowed shuttle pilots to explore the orbiter's low-speed flight and landing characteristics. The Enterprise provided realistic, in-flight simulations of how subsequent space shuttles would be flown at the end of an orbital mission. The fifth free flight, with the Enterprise landing on a concrete runway for the first time, revealed a problem with the space shuttle flight control system that made it susceptible to pilot-induced oscillation, a potentially dangerous control problem. Further research using various aircraft, particularly NASA Dryden's F-8 Digital-Fly-By-Wire testbed, led to correction of the problem before the first Orbital Test Flight.

Flight Tests of a 0.13-Scale Model of the Convair XFY-1 Vertically Rising Airplane in a Setup Simulating that Proposed for Captive-Flight Tests in a Hangar, TED No. NACA DE 368

NASA Technical Reports Server (NTRS)

Lovell, Powell M., Jr.

1953-01-01

An experimental investigation has been conducted to determine the dynamic stability and control characteristics of a 0.13-scale free-flight model of the Convair XFY-1 airplane in test setups representing the setup proposed for use in the first flight tests of the full-scale airplane in the Moffett Field airship hangar. The investigation was conducted in two parts: first, tests with the model flying freely in an enclosure simulating the hangar, and second, tests with the model partially restrained by an overhead line attached to the propeller spinner and ground lines attached to the wing and tail tips. The results of the tests indicated that the airplane can be flown without difficulty in the Moffett Field airship hangar if it does not approach too close to the hangar walls. If it does approach too close to the walls, the recirculation of the propeller slipstream might cause sudden trim changes which would make smooth flight difficult for the pilot to accomplish. It appeared that the tethering system proposed by Convair could provide generally satisfactory restraint of large-amplitude motions caused by control failure or pilot error without interfering with normal flying or causing any serious instability or violent jerking motions as the tethering lines restrained the model.

Dream Chaser ALT-2 Free Flight

NASA Image and Video Library

2017-11-11

Sierra Nevada Corp’s Dream Chaser was released from a helicopter for a landing on an Edwards Air Force Base runway after it was lifted from the ramp at NASA’s Armstrong Flight Research Center in California, for its successful approach and landing flight test on Nov. 11, 2017.

Piloted simulation study of an ILS approach of a twin-pusher business/commuter turboprop aircraft configuration

NASA Technical Reports Server (NTRS)

Riley, Donald R.; Brandon, Jay M.; Glaab, Louis J.

1994-01-01

A six-degree-of-freedom nonlinear simulation of a twin-pusher, turboprop business/commuter aircraft configuration representative of the Cessna ATPTB (Advanced turboprop test bed) was developed for use in piloted studies with the Langley General Aviation Simulator. The math models developed are provided, simulation predictions are compared with with Cessna flight-test data for validation purposes, and results of a handling quality study during simulated ILS (instrument landing system) approaches and missed approaches are presented. Simulated flight trajectories, task performance measures, and pilot evaluations are presented for the ILS approach and missed-approach tasks conducted with the vehicle in the presence of moderate turbulence, varying horizontal winds and engine-out conditions. Six test subjects consisting of two research pilots, a Cessna test pilot, and three general aviation pilots participated in the study. This effort was undertaken in cooperation with the Cessna Aircraft Company.

Flight Investigation of Effects of Transition, Landing Approaches, Partial-Power Vertical Descents, and Droop-Stop Pounding on the Bending and Torsional Moments Encountered by a Helicopter Rotor Blade

NASA Technical Reports Server (NTRS)

Ludi, LeRoy H.

1959-01-01

Flight tests have been conducted with a single-rotor helicopter, one blade of which was equipped at 14 percent and 40 percent of the blade radius with strain gages calibrated to measure moments rather than stresses, to determine the effects of transition, landing approaches, and partial-power vertical descents on the rotor-blade bending and torsional moments. In addition, ground tests were conducted to determine the effects of static droop-stop pounding on the rotor-blade moments. The results indicate that partial-power vertical descents and landing approaches produce rotor-blade moments that are higher than the moments encountered in any other flight condition investigated to date with this equipment. Decelerating through the transition region in level flight was found to result in higher vibratory moments than accelerating through this region. Deliberately induced static droop-stop pounding produced flapwise bending moments at the 14-percent-radius station which were as high as the moments experienced in landing approaches and partial-power vertical descents.

KSC-2014-4167

NASA Image and Video Library

2014-09-30

CAPE CANAVERAL, Fla. – A United Launch Alliance technicians drives the transporter that carries the Delta IV Heavy rocket to the pad at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. The rocket is secured on the Elevated Platform Transporter. The Delta IV Heavy will launch Orion on Exploration Flight Test-1. During its first flight test, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Dimitri Gerondidakis

KSC-2014-4168

NASA Image and Video Library

2014-09-30

CAPE CANAVERAL, Fla. – A United Launch Alliance technicians drives the transporter that carries the Delta IV Heavy rocket to the pad at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. The rocket is secured on the Elevated Platform Transporter. The Delta IV Heavy will launch Orion on Exploration Flight Test-1. During its first flight test, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Dimitri Gerondidakis

KSC-2014-4169

NASA Image and Video Library

2014-09-30

CAPE CANAVERAL, Fla. – A United Launch Alliance technicians drives the transporter that carries the Delta IV Heavy rocket to the pad at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. The rocket is secured on the Elevated Platform Transporter. The Delta IV Heavy will launch Orion on Exploration Flight Test-1. During its first flight test, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Dimitri Gerondidakis

KSC-2014-4163

NASA Image and Video Library

2014-09-30

CAPE CANAVERAL, Fla. – The United Launch Alliance Delta IV Heavy rocket exits the Horizontal Integration Facility at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. The rocket is secured on the Elevated Platform Transporter for the trip to the pad. The Delta IV Heavy will launch Orion on Exploration Flight Test-1. During its first flight test, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Dimitri Gerondidakis

Flight simulator fidelity assessment in a rotorcraft lateral translation maneuver

NASA Technical Reports Server (NTRS)

Hess, R. A.; Malsbury, T.; Atencio, A., Jr.

1992-01-01

A model-based methodology for assessing flight simulator fidelity in closed-loop fashion is exercised in analyzing a rotorcraft low-altitude maneuver for which flight test and simulation results were available. The addition of a handling qualities sensitivity function to a previously developed model-based assessment criteria allows an analytical comparison of both performance and handling qualities between simulation and flight test. Model predictions regarding the existence of simulator fidelity problems are corroborated by experiment. The modeling approach is used to assess analytically the effects of modifying simulator characteristics on simulator fidelity.

Automated Test for NASA CFS

NASA Technical Reports Server (NTRS)

McComas, David C.; Strege, Susanne L.; Carpenter, Paul B. Hartman, Randy

2015-01-01

The core Flight System (cFS) is a flight software (FSW) product line developed by the Flight Software Systems Branch (FSSB) at NASA's Goddard Space Flight Center (GSFC). The cFS uses compile-time configuration parameters to implement variable requirements to enable portability across embedded computing platforms and to implement different end-user functional needs. The verification and validation of these requirements is proving to be a significant challenge. This paper describes the challenges facing the cFS and the results of a pilot effort to apply EXB Solution's testing approach to the cFS applications.

Software control and system configuration management - A process that works

NASA Technical Reports Server (NTRS)

Petersen, K. L.; Flores, C., Jr.

1983-01-01

A comprehensive software control and system configuration management process for flight-crucial digital control systems of advanced aircraft has been developed and refined to insure efficient flight system development and safe flight operations. Because of the highly complex interactions among the hardware, software, and system elements of state-of-the-art digital flight control system designs, a systems-wide approach to configuration control and management has been used. Specific procedures are implemented to govern discrepancy reporting and reconciliation, software and hardware change control, systems verification and validation testing, and formal documentation requirements. An active and knowledgeable configuration control board reviews and approves all flight system configuration modifications and revalidation tests. This flexible process has proved effective during the development and flight testing of several research aircraft and remotely piloted research vehicles with digital flight control systems that ranged from relatively simple to highly complex, integrated mechanizations.

Preliminary flight test results of a fly-by-throttle emergency flight control system on an F-15 airplane

NASA Technical Reports Server (NTRS)

Burcham, Frank W., Jr.; Maine, Trindel A.; Fullerton, C. G.; Wells, Edward A.

1993-01-01

A multi-engine aircraft, with some or all of the flight control system inoperative, may use engine thrust for control. NASA Dryden has conducted a study of the capability and techniques for this emergency flight control method for the F-15 airplane. With an augmented control system, engine thrust, along with appropriate feedback parameters, is used to control flightpath and bank angle. Extensive simulation studies have been followed by flight tests. This paper discusses the principles of throttles-only control, the F-15 airplane, the augmented system, and the flight results including landing approaches with throttles-only control to within 10 ft of the ground.

Flight Test Comparison of Different Adaptive Augmentations for Fault Tolerant Control Laws for a Modified F-15 Aircraft

NASA Technical Reports Server (NTRS)

Burken, John J.; Hanson, Curtis E.; Lee, James A.; Kaneshige, John T.

2009-01-01

This report describes the improvements and enhancements to a neural network based approach for directly adapting to aerodynamic changes resulting from damage or failures. This research is a follow-on effort to flight tests performed on the NASA F-15 aircraft as part of the Intelligent Flight Control System research effort. Previous flight test results demonstrated the potential for performance improvement under destabilizing damage conditions. Little or no improvement was provided under simulated control surface failures, however, and the adaptive system was prone to pilot-induced oscillations. An improved controller was designed to reduce the occurrence of pilot-induced oscillations and increase robustness to failures in general. This report presents an analysis of the neural networks used in the previous flight test, the improved adaptive controller, and the baseline case with no adaptation. Flight test results demonstrate significant improvement in performance by using the new adaptive controller compared with the previous adaptive system and the baseline system for control surface failures.

Flight test of the X-29A at high angle of attack: Flight dynamics and controls

NASA Technical Reports Server (NTRS)

Bauer, Jeffrey E.; Clarke, Robert; Burken, John J.

1995-01-01

The NASA Dryden Flight Research Center has flight tested two X-29A aircraft at low and high angles of attack. The high-angle-of-attack tests evaluate the feasibility of integrated X-29A technologies. More specific objectives focus on evaluating the high-angle-of-attack flying qualities, defining multiaxis controllability limits, and determining the maximum pitch-pointing capability. A pilot-selectable gain system allows examination of tradeoffs in airplane stability and maneuverability. Basic fighter maneuvers provide qualitative evaluation. Bank angle captures permit qualitative data analysis. This paper discusses the design goals and approach for high-angle-of-attack control laws and provides results from the envelope expansion and handling qualities testing at intermediate angles of attack. Comparisons of the flight test results to the predictions are made where appropriate. The pitch rate command structure of the longitudinal control system is shown to be a valid design for high-angle-of-attack control laws. Flight test results show that wing rock amplitude was overpredicted and aileron and rudder effectiveness were underpredicted. Flight tests show the X-29A airplane to be a good aircraft up to 40 deg angle of attack.

RLV/X-33 operations overview

NASA Astrophysics Data System (ADS)

Black, Stephen T.; Eshleman, Wally

1997-01-01

This paper describes the VentureStar™ SSTO RLV and X-33 operations concepts. Applications of advanced technologies, automated ground support systems, advanced aircraft and launch vehicle lessons learned have been integrated to develop a streamlined vehicle and mission processing concept necessary to meet the goals of a commercial SSTO RLV. These concepts will be validated by the X-33 flight test program where financial and technical risk mitigation are required. The X-33 flight test program totally demonstrates the vehicle performance, technology, and efficient ground operations at the lowest possible cost. The Skunk Work's test program approach and test site proximity to the production plant are keys. The X-33 integrated flight and ground test program incrementally expands the knowledge base of the overall system allowing minimum risk progression to the next flight test program milestone. Subsequent X-33 turnaround processing flows will be performed with an aircraft operations philosophy. The differences will be based on research and development, component reliability and flight test requirements.

A flight-test and simulation evaluation of the longitudinal final approach and landing performance of an automatic system for a light wing loading STOL aircraft equipped with wing spoilers

NASA Technical Reports Server (NTRS)

Brown, S. C.; Hardy, G. H.; Hindson, W. S.

1984-01-01

As part of a comprehensive flight-test investigation of short takeoff and landing (STOL) operating systems for the terminal systems for the terminal area, an automatic landing system has been developed and evaluated for a light wing-loading turboprop-powered aircraft. An advanced digital avionics system performed display, navigation, guidance, and control functions for the test aircraft. Control signals were generated in order to command powered actuators for all conventional controls and for a set of symmetrically driven wing spoilers. This report describes effects of the spoiler control on longitudinal autoland (automatic landing) performance. Flight-test results, with and without spoiler control, are presented and compared with available (basically, conventional takeoff and landing) performance criteria. These comparisons are augmented by results from a comprehensive simulation of the controlled aircraft that included representations of the microwave landing system navigation errors that were encountered in flight as well as expected variations in atmospheric turbulence and wind shear. Flight-test results show that the addition of spoiler control improves the touchdown performance of the automatic landing system. Spoilers improve longitudinal touchdown and landing pitch-attitude performance, particularly in tailwind conditions. Furthermore, simulation results indicate that performance would probably be satisfactory for a wider range of atmospheric disturbances than those encountered in flight. Flight results also indicate that the addition of spoiler control during the final approach does not result in any measurable change in glidepath track performance, and results in a very small deterioration in airspeed tracking. This difference contrasts with simulations results, which indicate some improvement in glidepath tracking and no appreciable change in airspeed tracking. The modeling problem in the simulation that contributed to this discrepancy with flight was not resolved.

Integrated Testing Approaches for the NASA Ares I Crew Launch Vehicle

NASA Technical Reports Server (NTRS)

Taylor, James L.; Cockrell, Charles E.; Tuma, Margaret L.; Askins, Bruce R.; Bland, Jeff D.; Davis, Stephan R.; Patterson, Alan F.; Taylor, Terry L.; Robinson, Kimberly L.

2008-01-01

The Ares I crew launch vehicle is being developed by the U.S. National Aeronautics and Space Administration (NASA) to provide crew and cargo access to the International Space Station (ISS) and, together with the Ares V cargo launch vehicle, serves as a critical component of NASA's future human exploration of the Moon. During the preliminary design phase, NASA defined and began implementing plans for integrated ground and flight testing necessary to achieve the first human launch of Ares I. The individual Ares I flight hardware elements - including the first stage five segment booster (FSB), upper stage, and J-2X upper stage engine - will undergo extensive development, qualification, and certification testing prior to flight. Key integrated system tests include the upper stage Main Propulsion Test Article (MPTA), acceptance tests of the integrated upper stage and upper stage engine assembly, a full-scale integrated vehicle ground vibration test (IVGVT), aerodynamic testing to characterize vehicle performance, and integrated testing of the avionics and software components. The Ares I-X development flight test will provide flight data to validate engineering models for aerodynamic performance, stage separation, structural dynamic performance, and control system functionality. The Ares I-Y flight test will validate ascent performance of the first stage, stage separation functionality, validate the ability of the upper stage to manage cryogenic propellants to achieve upper stage engine start conditions, and a high-altitude demonstration of the launch abort system (LAS) following stage separation. The Orion 1 flight test will be conducted as a full, un-crewed, operational flight test through the entire ascent flight profile prior to the first crewed launch.

Integrated System Test Approaches for the NASA Ares I Crew Launch Vehicle

NASA Technical Reports Server (NTRS)

Cockrell, Charles E., Jr.; Askins, Bruce R.; Bland, Jeffrey; Davis, Stephan; Holladay, Jon B.; Taylor, James L.; Taylor, Terry L.; Robinson, Kimberly F.; Roberts, Ryan E.; Tuma, Margaret

2007-01-01

The Ares I Crew Launch Vehicle (CLV) is being developed by the U.S. National Aeronautics and Space Administration (NASA) to provide crew access to the International Space Station (ISS) and, together with the Ares V Cargo Launch Vehicle (CaLV), serves as one component of a future launch capability for human exploration of the Moon. During the system requirements definition process and early design cycles, NASA defined and began implementing plans for integrated ground and flight testing necessary to achieve the first human launch of Ares I. The individual Ares I flight hardware elements: the first stage five segment booster (FSB), upper stage, and J-2X upper stage engine, will undergo extensive development, qualification, and certification testing prior to flight. Key integrated system tests include the Main Propulsion Test Article (MPTA), acceptance tests of the integrated upper stage and upper stage engine assembly, a full-scale integrated vehicle dynamic test (IVDT), aerodynamic testing to characterize vehicle performance, and integrated testing of the avionics and software components. The Ares I-X development flight test will provide flight data to validate engineering models for aerodynamic performance, stage separation, structural dynamic performance, and control system functionality. The Ares I-Y flight test will validate ascent performance of the first stage, stage separation functionality, and a highaltitude actuation of the launch abort system (LAS) following separation. The Orion-1 flight test will be conducted as a full, un-crewed, operational flight test through the entire ascent flight profile prior to the first crewed launch.

Dynamics stability derivatives of space shuttle orbiter obtained from wind-tunnel and approach and landing flight tests

NASA Technical Reports Server (NTRS)

Freeman, D. C., Jr.

1980-01-01

A comparison was made between ground facility measurements, the aerodynamic design data book values, and the dynamic damping derivatives extracted from the space shuttle orbiter approach and landing flight tests. The comparison covers an angle of attack range from 2 deg to 10 deg at subsonic Mach numbers. The parameters of pitch, yaw, and roll damping, as well as the yawing moment due to rolling velocity and rolling moment due to yawing velocity are compared.

A historical overview of flight flutter testing

NASA Technical Reports Server (NTRS)

Kehoe, Michael W.

1995-01-01

This paper reviews the test techniques developed over the last several decades for flight flutter testing of aircraft. Structural excitation systems, instrumentation systems, digital data preprocessing, and parameter identification algorithms (for frequency and damping estimates from the response data) are described. Practical experiences and example test programs illustrate the combined, integrated effectiveness of the various approaches used. Finally, comments regarding the direction of future developments and needs are presented.

Recommended Changes to Interval Management to Achieve Operational Implementation

NASA Technical Reports Server (NTRS)

Baxley, Brian; Swieringa, Kurt; Roper, Roy; Hubbs, Clay; Goess, Paul; Shay, Richard

2017-01-01

A 19-day flight test of an Interval Management (IM) avionics prototype was conducted in Washington State using three aircraft to precisely achieve and maintain a spacing interval behind the preceding aircraft. NASA contracted with Boeing, Honeywell, and United Airlines to build this prototype, and then worked closely with them, the FAA, and other industry partners to test this prototype in flight. Four different IM operation types were investigated during this test in the en route, arrival, and final approach phases of flight. Many of the IM operations met or exceeded the design goals established prior to the test. However, there were issues discovered throughout the flight test, including the rate and magnitude of IM commanded speed changes and the difference between expected and actual aircraft deceleration rates.

Convection Weather Detection by General Aviation Pilots with Convectional and Data-Linked Graphical Weather Information Sources

NASA Technical Reports Server (NTRS)

Chamberlain, James P.; Latorella, Kara A.

2001-01-01

This study compares how well general aviation (GA) pilots detect convective weather in flight with different weather information sources. A flight test was conducted in which GA pilot test subjects were given different in-flight weather information cues and flown toward convective weather of moderate or greater intensity. The test subjects were not actually flying the aircraft, but were given pilot tasks representative of the workload and position awareness requirements of the en route portion of a cross country GA flight. On each flight, one test subject received weather cues typical of a flight in visual meteorological conditions (VMC), another received cues typical of flight in instrument meteorological conditions (IMC), and a third received cues typical of flight in IMC but augmented with a graphical weather information system (GWIS). The GWIS provided the subject with near real time data-linked weather products, including a weather radar mosaic superimposed on a moving map with a symbol depicting the aircraft's present position and direction of track. At several points during each flight, the test subjects completed short questionnaires which included items addressing their weather situation awareness and flight decisions. In particular, test subjects were asked to identify the location of the nearest convective cells. After the point of nearest approach to convective weather, the test subjects were asked to draw the location of convective weather on an aeronautical chart, along with the aircraft's present position. This paper reports preliminary results on how accurately test subjects provided with these different weather sources could identify the nearest cell of moderate or greater intensity along their route of flight. Additional flight tests are currently being conducted to complete the data set.

Flight-test evaluation of two electronic display formats for approach to landing under instrument conditions

NASA Technical Reports Server (NTRS)

Morello, S. A.; Knox, C. E.; Steinmetz, G. G.

1977-01-01

The results of a flight evaluation of two electronic display formats for the approach to landing under instrument conditions are presented. The evaluation was conducted for a base-line electronic display format and for the same format with runway symbology and track information added. The evaluation was conducted during 3 deg, manual straight-in approaches with and without initial localizer offsets. Flight path tracking performance data and pilot subjective comments were examined with regard to the pilot's ability to capture and maintain localizer and glide slope by using both display formats.

Analyses of Shuttle Orbiter approach and landing

NASA Technical Reports Server (NTRS)

Ashkenas, I. L.; Hoh, R. H.; Teper, G. L.

1982-01-01

A study of the Shuttle Orbiter approach and landing conditions is summarized. The causes of observed PIO-like flight deficiencies are listed, and possible corrective measures are examined. Closed-loop pilot/vehicle analyses are described, and a description is given of path-attitude stability boundaries. The latter novel approach is found to be of great value in delineating and illustrating the basic causes of this multiloop pilot control problem. It is shown that the analytical results are consistent with flight test and fixed-base simulation. Conclusions are drawn concerning possible improvements in the Shuttle Orbiter/Digital Flight Control System.

Development of a remote digital augmentation system and application to a remotely piloted research vehicle

NASA Technical Reports Server (NTRS)

Edwards, J. W.; Deets, D. A.

1975-01-01

A cost-effective approach to flight testing advanced control concepts with remotely piloted vehicles is described. The approach utilizes a ground based digital computer coupled to the remotely piloted vehicle's motion sensors and control surface actuators through telemetry links to provide high bandwidth feedback control. The system was applied to the control of an unmanned 3/8-scale model of the F-15 airplane. The model was remotely augmented; that is, the F-15 mechanical and control augmentation flight control systems were simulated by the ground-based computer, rather than being in the vehicle itself. The results of flight tests of the model at high angles of attack are discussed.

Dream Chaser ALT-2 Free Flight

NASA Image and Video Library

2017-11-11

Sierra Nevada Corp’s Dream Chaser facing sunrise over Rogers Dry Lake by NASA Armstrong Flight Research Center in California where it was being prepared for a successful approach and landing test Nov. 11, 2017.

Airborne testing and demonstration of a new flight system based on an Aerodyne N2O-CO2-CO-H2O mini-spectrometer

NASA Astrophysics Data System (ADS)

Gvakharia, A.; Kort, E. A.; Smith, M. L.; Conley, S.

2017-12-01

Nitrous oxide (N2O) is a powerful greenhouse gas and ozone depleting substance. With high atmospheric backgrounds and small relative signals, N2O emissions have been challenging to observe and understand on regional scales with traditional instrumentation. Fast-response airborne measurements with high precision and accuracy can potentially bridge this observational gap. Here we present flight assessments of a new flight system based on an Aerodyne mini-spectrometer as well as a Los Gatos N2O/CO analyzer during the Fertilizer Emissions Airborne Study (FEAST). With the Scientific Aviation Mooney aircraft, we conducted test flights for both analyzers where a known calibration gas was sampled throughout the flight (`null' tests). Clear altitude/cabin-pressure dependencies were observed for both analyzers if operated in an "off-the-shelf' manner. For the remainder of test flights and the FEAST campaign we used a new flight system based on an Aerodyne mini-spectrometer with the addition of a custom pressure control/calibration system. Instead of using traditional approaches with spectral-zeros and infrequent in-flight calibrations, we employ a high-flow system with stable flow control to enable high frequency (2 minutes), short duration (15 seconds) sampling of a known calibration gas. This approach, supported by the null test, enables correction for spectral drift caused by a variety of factors while maintaining a 90% duty cycle for 1Hz sampling from an aircraft. Preliminary in-flight precisions are estimated at 0.05 ppb, 0.1 ppm, 1 ppb, and 10 ppm for N2O, CO2, CO, and H2O respectively. We also present a further 40 hours of inter-comparison in flight with a Picarro 2301-f ring-down spectrometer demonstrating consistency between CO2 and H2O measurements and no altitude dependent error.

Flight Test Comparison of Synthetic Vision Display Concepts at Dallas/Fort Worth International Airport

NASA Technical Reports Server (NTRS)

Glaab, Louis J.; Kramer, Lynda J.; Arthur, Trey; Parrish, Russell V.; Barry, John S.

2003-01-01

Limited visibility is the single most critical factor affecting the safety and capacity of worldwide aviation operations. Synthetic Vision Systems (SVS) technology can solve this visibility problem with a visibility solution. These displays employ computer-generated terrain imagery to present 3D, perspective out-the-window scenes with sufficient information and realism to enable operations equivalent to those of a bright, clear day, regardless of weather conditions. To introduce SVS display technology into as many existing aircraft as possible, a retrofit approach was defined that employs existing HDD display capabilities for glass cockpits and HUD capabilities for the other aircraft. This retrofit approach was evaluated for typical nighttime airline operations at a major international airport. Overall, 6 evaluation pilots performed 75 research approaches, accumulating 18 hours flight time evaluating SVS display concepts that used the NASA LaRC's Boeing B-757-200 aircraft at Dallas/Fort Worth International Airport. Results from this flight test establish the SVS retrofit concept, regardless of display size, as viable for tested conditions. Future assessments need to extend evaluation of the approach to operations in an appropriate, terrain-challenged environment with daytime test conditions.

Efficient Testing Combining Design of Experiment and Learn-to-Fly Strategies

NASA Technical Reports Server (NTRS)

Murphy, Patrick C.; Brandon, Jay M.

2017-01-01

Rapid modeling and efficient testing methods are important in a number of aerospace applications. In this study efficient testing strategies were evaluated in a wind tunnel test environment and combined to suggest a promising approach for both ground-based and flight-based experiments. Benefits of using Design of Experiment techniques, well established in scientific, military, and manufacturing applications are evaluated in combination with newly developing methods for global nonlinear modeling. The nonlinear modeling methods, referred to as Learn-to-Fly methods, utilize fuzzy logic and multivariate orthogonal function techniques that have been successfully demonstrated in flight test. The blended approach presented has a focus on experiment design and identifies a sequential testing process with clearly defined completion metrics that produce increased testing efficiency.

Implementation of an Adaptive Controller System from Concept to Flight Test

NASA Technical Reports Server (NTRS)

Larson, Richard R.; Burken, John J.; Butler, Bradley S.; Yokum, Steve

2009-01-01

The National Aeronautics and Space Administration Dryden Flight Research Center (Edwards, California) is conducting ongoing flight research using adaptive controller algorithms. A highly modified McDonnell-Douglas NF-15B airplane called the F-15 Intelligent Flight Control System (IFCS) is used to test and develop these algorithms. Modifications to this airplane include adding canards and changing the flight control systems to interface a single-string research controller processor for neural network algorithms. Research goals include demonstration of revolutionary control approaches that can efficiently optimize aircraft performance in both normal and failure conditions and advancement of neural-network-based flight control technology for new aerospace system designs. This report presents an overview of the processes utilized to develop adaptive controller algorithms during a flight-test program, including a description of initial adaptive controller concepts and a discussion of modeling formulation and performance testing. Design finalization led to integration with the system interfaces, verification of the software, validation of the hardware to the requirements, design of failure detection, development of safety limiters to minimize the effect of erroneous neural network commands, and creation of flight test control room displays to maximize human situational awareness; these are also discussed.

Aeroservoelastic Modeling of Body Freedom Flutter for Control System Design

NASA Technical Reports Server (NTRS)

Ouellette, Jeffrey

2017-01-01

The communication of this method is being used by NASA in the ongoing collaborations with groups interested in the X-56A flight test program. Model generation for body freedom flutter Addressing issues in: State Consistency, Low frequency dynamics, Unsteady aerodynamics. Applied approach to X-56A MUTT: Comparing to flight test data.

Aerial photography flight quality assessment with GPS/INS and DEM data

NASA Astrophysics Data System (ADS)

Zhao, Haitao; Zhang, Bing; Shang, Jiali; Liu, Jiangui; Li, Dong; Chen, Yanyan; Zuo, Zhengli; Chen, Zhengchao

2018-01-01

The flight altitude, ground coverage, photo overlap, and other acquisition specifications of an aerial photography flight mission directly affect the quality and accuracy of the subsequent mapping tasks. To ensure smooth post-flight data processing and fulfill the pre-defined mapping accuracy, flight quality assessments should be carried out in time. This paper presents a novel and rigorous approach for flight quality evaluation of frame cameras with GPS/INS data and DEM, using geometric calculation rather than image analysis as in the conventional methods. This new approach is based mainly on the collinearity equations, in which the accuracy of a set of flight quality indicators is derived through a rigorous error propagation model and validated with scenario data. Theoretical analysis and practical flight test of an aerial photography mission using an UltraCamXp camera showed that the calculated photo overlap is accurate enough for flight quality assessment of 5 cm ground sample distance image, using the SRTMGL3 DEM and the POSAV510 GPS/INS data. An even better overlap accuracy could be achieved for coarser-resolution aerial photography. With this new approach, the flight quality evaluation can be conducted on site right after landing, providing accurate and timely information for decision making.

Autonomous RPRV Navigation, Guidance and Control

NASA Technical Reports Server (NTRS)

Johnston, Donald E.; Myers, Thomas T.; Zellner, John W.

1983-01-01

Dryden Flight Research Center has the responsibility for flight testing of advanced remotely piloted research vehicles (RPRV) to explore highly maneuverable aircraft technology, and to test advanced structural concepts, and related aeronautical technologies which can yield important research results with significant cost benefits. The primary purpose is to provide the preliminary design of an upgraded automatic approach and landing control system and flight director display to improve landing performance and reduce pilot workload. A secondary purpose is to determine the feasibility of an onboard autonomous navigation, orbit, and landing capability for safe vehicle recovery in the event of loss of telemetry uplink communication with the vehicles. The current RPRV approach and landing method, the proposed automatic and manual approach and autoland system, and an autonomous navigation, orbit, and landing system concept which is based on existing operational technology are described.

Annual report to the NASA Administrator by the Aerospace Safety Advisory Panel on the space shuttle program. Part 1: Observations and conclusions

NASA Technical Reports Server (NTRS)

1977-01-01

The panel reviewed the following areas of major significance for the Approach and Landing Test program: mission planning and crew training, flight-readiness of the Carrier Aircraft and the Orbiter, including its flight control and avionics system, facilities, and communications and ground support equipment. The management system for risk assessment was investigated. The Orbital Flight Test Program was also reviewed. Observations and recommendations are presented.

Development and Flight Test of an Emergency Flight Control System Using Only Engine Thrust on an MD-11 Transport Airplane

NASA Technical Reports Server (NTRS)

Burcham, Frank W., Jr.; Burken, John J.; Maine, Trindel A.; Fullerton, C. Gordon

1997-01-01

An emergency flight control system that uses only engine thrust, called the propulsion-controlled aircraft (PCA) system, was developed and flight tested on an MD-11 airplane. The PCA system is a thrust-only control system, which augments pilot flightpath and track commands with aircraft feedback parameters to control engine thrust. The PCA system was implemented on the MD-11 airplane using only software modifications to existing computers. Results of a 25-hr flight test show that the PCA system can be used to fly to an airport and safely land a transport airplane with an inoperative flight control system. In up-and-away operation, the PCA system served as an acceptable autopilot capable of extended flight over a range of speeds, altitudes, and configurations. PCA approaches, go-arounds, and three landings without the use of any normal flight controls were demonstrated, including ILS-coupled hands-off landings. PCA operation was used to recover from an upset condition. The PCA system was also tested at altitude with all three hydraulic systems turned off. This paper reviews the principles of throttles-only flight control, a history of accidents or incidents in which some or all flight controls were lost, the MD-11 airplane and its systems, PCA system development, operation, flight testing, and pilot comments.

Fused Reality for Enhanced Flight Test Capabilities

NASA Technical Reports Server (NTRS)

Bachelder, Ed; Klyde, David

2011-01-01

The feasibility of using Fused Reality-based simulation technology to enhance flight test capabilities has been investigated. In terms of relevancy to piloted evaluation, there remains no substitute for actual flight tests, even when considering the fidelity and effectiveness of modern ground-based simulators. In addition to real-world cueing (vestibular, visual, aural, environmental, etc.), flight tests provide subtle but key intangibles that cannot be duplicated in a ground-based simulator. There is, however, a cost to be paid for the benefits of flight in terms of budget, mission complexity, and safety, including the need for ground and control-room personnel, additional aircraft, etc. A Fused Reality(tm) (FR) Flight system was developed that allows a virtual environment to be integrated with the test aircraft so that tasks such as aerial refueling, formation flying, or approach and landing can be accomplished without additional aircraft resources or the risk of operating in close proximity to the ground or other aircraft. Furthermore, the dynamic motions of the simulated objects can be directly correlated with the responses of the test aircraft. The FR Flight system will allow real-time observation of, and manual interaction with, the cockpit environment that serves as a frame for the virtual out-the-window scene.

Practical Application of a Subscale Transport Aircraft for Flight Research in Control Upset and Failure Conditions

NASA Technical Reports Server (NTRS)

Cunningham, Kevin; Foster, John V.; Morelli, Eugene A.; Murch, Austin M.

2008-01-01

Over the past decade, the goal of reducing the fatal accident rate of large transport aircraft has resulted in research aimed at the problem of aircraft loss-of-control. Starting in 1999, the NASA Aviation Safety Program initiated research that included vehicle dynamics modeling, system health monitoring, and reconfigurable control systems focused on flight regimes beyond the normal flight envelope. In recent years, there has been an increased emphasis on adaptive control technologies for recovery from control upsets or failures including damage scenarios. As part of these efforts, NASA has developed the Airborne Subscale Transport Aircraft Research (AirSTAR) flight facility to allow flight research and validation, and system testing for flight regimes that are considered too risky for full-scale manned transport airplane testing. The AirSTAR facility utilizes dynamically-scaled vehicles that enable the application of subscale flight test results to full scale vehicles. This paper describes the modeling and simulation approach used for AirSTAR vehicles that supports the goals of efficient, low-cost and safe flight research in abnormal flight conditions. Modeling of aerodynamics, controls, and propulsion will be discussed as well as the application of simulation to flight control system development, test planning, risk mitigation, and flight research.

KSC-2014-4160

NASA Image and Video Library

2014-09-30

CAPE CANAVERAL, Fla. – Inside the Horizontal Integration Facility at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida, the Delta IV Heavy rocket is ready for rollout to the pad. The rocket is secured on the Elevated Platform Transporter for the trip to the pad. The Delta IV Heavy will launch Orion on Exploration Flight Test-1. During its first flight test, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Dimitri Gerondidakis

KSC-2014-4166

NASA Image and Video Library

2014-09-30

CAPE CANAVERAL, Fla. – The United Launch Alliance, or ULA, Delta IV Heavy rocket has exited the Horizontal Integration Facility at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. ULA technicians help guide the rocket, secured on the Elevated Platform Transporter, for the trip to the pad. The Delta IV Heavy will launch Orion on Exploration Flight Test-1. During its first flight test, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Dimitri Gerondidakis

KSC-2014-4159

NASA Image and Video Library

2014-09-30

CAPE CANAVERAL, Fla. – Inside the Horizontal Integration Facility at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida, United Launch Alliance technicians prepare the Delta IV Heavy rocket for rollout to the pad. The rocket is secured on the Elevated Platform Transporter for the trip to the pad. The Delta IV Heavy will launch Orion on Exploration Flight Test-1. During its first flight test, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Dimitri Gerondidakis

KSC-2014-4157

NASA Image and Video Library

2014-09-30

CAPE CANAVERAL, Fla. – Inside the Horizontal Integration Facility at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida, United Launch Alliance technicians prepare the Delta IV Heavy rocket for rollout to the pad. The rocket is secured on the Elevated Platform Transporter for the trip to the pad. The Delta IV Heavy will launch Orion on Exploration Flight Test-1. During its first flight test, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Dimitri Gerondidakis

KSC-2014-4165

NASA Image and Video Library

2014-09-30

CAPE CANAVERAL, Fla. – The United Launch Alliance, or ULA, Delta IV Heavy rocket has exited the Horizontal Integration Facility at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. ULA technicians help guide the rocket, secured on the Elevated Platform Transporter, for the trip to the pad. The Delta IV Heavy will launch Orion on Exploration Flight Test-1. During its first flight test, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Dimitri Gerondidakis

KSC-2014-4162

NASA Image and Video Library

2014-09-30

CAPE CANAVERAL, Fla. – The United Launch Alliance Delta IV Heavy rocket begins to rollout from the Horizontal Integration Facility at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. The rocket is secured on the Elevated Platform Transporter for the trip to the pad. The Delta IV Heavy will launch Orion on Exploration Flight Test-1. During its first flight test, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Dimitri Gerondidakis

KSC-2014-4158

NASA Image and Video Library

2014-09-30

CAPE CANAVERAL, Fla. – Inside the Horizontal Integration Facility at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida, United Launch Alliance technicians prepare the Delta IV Heavy rocket for rollout to the pad. The rocket is secured on the Elevated Platform Transporter for the trip to the pad. The Delta IV Heavy will launch Orion on Exploration Flight Test-1. During its first flight test, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Dimitri Gerondidakis

Integrated System Test Approaches for the NASA Ares I Crew Launch Vehicle

NASA Technical Reports Server (NTRS)

Cockrell, Charles

2008-01-01

NASA is maturing test and evaluation plans leading to flight readiness of the Ares I crew launch vehicle. Key development, qualification, and verification tests are planned . Upper stage engine sea-level and altitude testing. First stage development and qualification motors. Upper stage structural and thermal development and qualification test articles. Main Propulsion Test Article (MPTA). Upper stage green run testing. Integrated Vehicle Ground Vibration Testing (IVGVT). Aerodynamic characterization testing. Test and evaluation supports initial validation flights (Ares I-Y and Orion 1) and design certification.

Flight test results from the CV990 simulated space shuttle during unpowered automatic approaches and landings

NASA Technical Reports Server (NTRS)

Edwards, F. G.; Foster, J. D.

1973-01-01

Unpowered automatic approaches and landings with a CV990 aircraft were conducted to study navigation, guidance, and control problems associated with terminal area approach and landing for the space shuttle. The flight tests were designed to study from 11,300 m to touchdown the performance of a navigation and guidance concept which utilized blended radio/inertial navigation using VOR, DME, and ILS as the ground navigation aids. In excess of fifty automatic approaches and landings were conducted. Preliminary results indicate that this concept may provide sufficient accuracy to accomplish automatic landing of the shuttle orbiter without air-breathing engines on a conventional size runway.

NASA Research For Instrument Approaches To Closely Spaced Parallel Runways

NASA Technical Reports Server (NTRS)

Elliott, Dawn M.; Perry, R. Brad

2000-01-01

Within the NASA Aviation Systems Capacity Program, the Terminal Area Productivity (TAP) Project is addressing airport capacity enhancements during instrument meteorological condition (IMC). The Airborne Information for Lateral Spacing (AILS) research within TAP has focused on an airborne centered approach for independent instrument approaches to closely spaced parallel runways using Differential Global Positioning System (DGPS) and Automatic Dependent Surveillance-Broadcast (ADS-B) technologies. NASA Langley Research Center (LaRC), working in partnership with Honeywell, Inc., completed in AILS simulation study, flight test, and demonstration in 1999 examining normal approaches and potential collision scenarios to runways with separation distances of 3,400 and 2,500 feet. The results of the flight test and demonstration validate the simulation study.

Structure Computation of Quiet Spike[Trademark] Flight-Test Data During Envelope Expansion

NASA Technical Reports Server (NTRS)

Kukreja, Sunil L.

2008-01-01

System identification or mathematical modeling is used in the aerospace community for development of simulation models for robust control law design. These models are often described as linear time-invariant processes. Nevertheless, it is well known that the underlying process is often nonlinear. The reason for using a linear approach has been due to the lack of a proper set of tools for the identification of nonlinear systems. Over the past several decades, the controls and biomedical communities have made great advances in developing tools for the identification of nonlinear systems. These approaches are robust and readily applicable to aerospace systems. In this paper, we show the application of one such nonlinear system identification technique, structure detection, for the analysis of F-15B Quiet Spike(TradeMark) aeroservoelastic flight-test data. Structure detection is concerned with the selection of a subset of candidate terms that best describe the observed output. This is a necessary procedure to compute an efficient system description that may afford greater insight into the functionality of the system or a simpler controller design. Structure computation as a tool for black-box modeling may be of critical importance for the development of robust parsimonious models for the flight-test community. Moreover, this approach may lead to efficient strategies for rapid envelope expansion, which may save significant development time and costs. The objectives of this study are to demonstrate via analysis of F-15B Quiet Spike aeroservoelastic flight-test data for several flight conditions that 1) linear models are inefficient for modeling aeroservoelastic data, 2) nonlinear identification provides a parsimonious model description while providing a high percent fit for cross-validated data, and 3) the model structure and parameters vary as the flight condition is altered.

A review of recent developments in flight test techniques at the Ames Research Center, Dryden Flight Research Facility

NASA Technical Reports Server (NTRS)

Layton, G. P.

1984-01-01

New flight test techniques in use at Ames Dryden are reviewed. The use of the pilot in combination with ground and airborne computational capabilities to maximize data return is discussed, including the remotely piloted research vehicle technique for high-risk testing, the remotely augmented vehicle technique for handling qualities research, and use of ground computed flight director information to fly unique profiles such as constant Reynolds number profiles through the transonic flight regime. Techniques used for checkout and design verification of systems-oriented aircraft are discussed, including descriptions of the various simulations, iron bird setups, and vehicle tests. Some newly developed techniques to support the aeronautical research disciplines are discussed, including a new approach to position-error determination, and the use of a large skin friction balance for the measurement of drag caused by various excrescencies.

A rule-based system for real-time analysis of control systems

NASA Astrophysics Data System (ADS)

Larson, Richard R.; Millard, D. Edward

1992-10-01

An approach to automate the real-time analysis of flight critical health monitoring and system status is being developed and evaluated at the NASA Dryden Flight Research Facility. A software package was developed in-house and installed as part of the extended aircraft interrogation and display system. This design features a knowledge-base structure in the form of rules to formulate interpretation and decision logic of real-time data. This technique has been applied for ground verification and validation testing and flight testing monitoring where quick, real-time, safety-of-flight decisions can be very critical. In many cases post processing and manual analysis of flight system data are not required. The processing is described of real-time data for analysis along with the output format which features a message stack display. The development, construction, and testing of the rule-driven knowledge base, along with an application using the X-31A flight test program, are presented.

The X-31A quasi-tailless flight test results

NASA Technical Reports Server (NTRS)

Bosworth, John T.; Stoliker, P. C.

1996-01-01

A quasi-tailless flight investigation was launched using the X-31A enhanced fighter maneuverability airplane. In-flight simulations were used to assess the effect of partial to total vertical tail removal. The rudder control surface was used to cancel the stabilizing effects of the vertical tail, and yaw thrust vector commands were used to restabilize and control the airplane. The quasi-tailless mode was flown supersonically with gentle maneuvering and subsonically in precision approaches and ground attack profiles. Pilot ratings and a full set of flight test measurements were recorded. This report describes the results obtained and emphasizes the lessons learned from the X-31A flight test experiment. Sensor-related issues and their importance to a quasi-tailless simulation and to ultimately controlling a directionally unstable vehicle are assessed. The X-31A quasi-tailless flight test experiment showed that tailless and reduced tail fighter aircraft are definitely feasible. When the capability is designed into the airplane from the beginning, the benefits have the potential to outweigh the added complexity required.

A rule-based system for real-time analysis of control systems

NASA Technical Reports Server (NTRS)

Larson, Richard R.; Millard, D. Edward

1992-01-01

An approach to automate the real-time analysis of flight critical health monitoring and system status is being developed and evaluated at the NASA Dryden Flight Research Facility. A software package was developed in-house and installed as part of the extended aircraft interrogation and display system. This design features a knowledge-base structure in the form of rules to formulate interpretation and decision logic of real-time data. This technique has been applied for ground verification and validation testing and flight testing monitoring where quick, real-time, safety-of-flight decisions can be very critical. In many cases post processing and manual analysis of flight system data are not required. The processing is described of real-time data for analysis along with the output format which features a message stack display. The development, construction, and testing of the rule-driven knowledge base, along with an application using the X-31A flight test program, are presented.

Flight Measurements of the Effect of a Controllable Thrust Reverser on the Flight Characteristics of a Single-Engine Jet Airplane

NASA Technical Reports Server (NTRS)

Anderson, Seth B.; Cooper, George E.; Faye, Alan E., Jr.

1959-01-01

A flight investigation was undertaken to determine the effect of a fully controllable thrust reverser on the flight characteristics of a single-engine jet airplane. Tests were made using a cylindrical target-type reverser actuated by a hydraulic cylinder through a "beep-type" cockpit control mounted at the base of the throttle. The thrust reverser was evaluated as an in-flight decelerating device, as a flight path control and airspeed control in landing approach, and as a braking device during the ground roll. Full deflection of the reverser for one reverser configuration resulted in a reverse thrust ratio of as much as 85 percent, which at maximum engine power corresponded to a reversed thrust of 5100 pounds. Use of the reverser in landing approach made possible a wide selection of approach angles, a large reduction in approach speed at steep approach angles, improved control of flight path angle, and more accuracy in hitting a given touchdown point. The use of the reverser as a speed brake at lower airspeeds was compromised by a longitudinal trim change. At the lower airspeeds and higher engine powers there was insufficient elevator power to overcome the nose-down trim change at full reverser deflection.

SLS Flight Software Testing: Using a Modified Agile Software Testing Approach

NASA Technical Reports Server (NTRS)

Bolton, Albanie T.

2016-01-01

NASA's Space Launch System (SLS) is an advanced launch vehicle for a new era of exploration beyond earth's orbit (BEO). The world's most powerful rocket, SLS, will launch crews of up to four astronauts in the agency's Orion spacecraft on missions to explore multiple deep-space destinations. Boeing is developing the SLS core stage, including the avionics that will control vehicle during flight. The core stage will be built at NASA's Michoud Assembly Facility (MAF) in New Orleans, LA using state-of-the-art manufacturing equipment. At the same time, the rocket's avionics computer software is being developed here at Marshall Space Flight Center in Huntsville, AL. At Marshall, the Flight and Ground Software division provides comprehensive engineering expertise for development of flight and ground software. Within that division, the Software Systems Engineering Branch's test and verification (T&V) team uses an agile test approach in testing and verification of software. The agile software test method opens the door for regular short sprint release cycles. The idea or basic premise behind the concept of agile software development and testing is that it is iterative and developed incrementally. Agile testing has an iterative development methodology where requirements and solutions evolve through collaboration between cross-functional teams. With testing and development done incrementally, this allows for increased features and enhanced value for releases. This value can be seen throughout the T&V team processes that are documented in various work instructions within the branch. The T&V team produces procedural test results at a higher rate, resolves issues found in software with designers at an earlier stage versus at a later release, and team members gain increased knowledge of the system architecture by interfacing with designers. SLS Flight Software teams want to continue uncovering better ways of developing software in an efficient and project beneficial manner. Through agile testing, there has been increased value through individuals and interactions over processes and tools, improved customer collaboration, and improved responsiveness to changes through controlled planning. The presentation will describe agile testing methodology as taken with the SLS FSW Test and Verification team at Marshall Space Flight Center.

KSC-2009-5848

NASA Image and Video Library

2009-10-23

CAPE CANAVERAL, Fla. - As nightfall comes to Launch Complex 39B at NASA's Kennedy Space Center in Florida, xenon lights illuminate the pad and the Ares I-X rocket awaiting the approaching liftoff of its flight test. This is the first time since the Apollo Program's Saturn rockets were retired that a vehicle other than the space shuttle has occupied the pad. Part of the Constellation Program, the Ares I-X is the test vehicle for the Ares I. The Ares I-X flight test is set for Oct. 27. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Kim Shiflett

KSC-2009-5849

NASA Image and Video Library

2009-10-23

CAPE CANAVERAL, Fla. - As nightfall comes to Launch Complex 39B at NASA's Kennedy Space Center in Florida, xenon lights illuminate the pad and the Ares I-X rocket awaiting the approaching liftoff of its flight test. This is the first time since the Apollo Program's Saturn rockets were retired that a vehicle other than the space shuttle has occupied the pad. Part of the Constellation Program, the Ares I-X is the test vehicle for the Ares I. The Ares I-X flight test is set for Oct. 27. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Kim Shiflett

KSC-2009-5850

NASA Image and Video Library

2009-10-23

CAPE CANAVERAL, Fla. - As nightfall comes to Launch Complex 39B at NASA's Kennedy Space Center in Florida, xenon lights illuminate the pad and the Ares I-X rocket awaiting the approaching liftoff of its flight test. This is the first time since the Apollo Program's Saturn rockets were retired that a vehicle other than the space shuttle has occupied the pad. Part of the Constellation Program, the Ares I-X is the test vehicle for the Ares I. The Ares I-X flight test is set for Oct. 27. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Kim Shiflett

KSC-2009-5859

NASA Image and Video Library

2009-10-23

CAPE CANAVERAL, Fla. - As night settles over Launch Complex 39B at NASA's Kennedy Space Center in Florida, xenon lights reveal the Ares I-X rocket awaiting the approaching liftoff of its flight test. This is the first time since the Apollo Program's Saturn rockets were retired that a vehicle other than the space shuttle has occupied the pad. Part of the Constellation Program, the Ares I-X is the test vehicle for the Ares I. The Ares I-X flight test is set for Oct. 27. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Kim Shiflett

KSC-2009-5860

NASA Image and Video Library

2009-10-23

CAPE CANAVERAL, Fla. - As night settles over Launch Complex 39B at NASA's Kennedy Space Center in Florida, xenon lights reveal the Ares I-X rocket awaiting the approaching liftoff of its flight test. This is the first time since the Apollo Program's Saturn rockets were retired that a vehicle other than the space shuttle has occupied the pad. Part of the Constellation Program, the Ares I-X is the test vehicle for the Ares I. The Ares I-X flight test is set for Oct. 27. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Kim Shiflett

KSC-2009-5852

NASA Image and Video Library

2009-10-23

CAPE CANAVERAL, Fla. - As nightfall comes to Launch Complex 39B at NASA's Kennedy Space Center in Florida, xenon lights reveal the Ares I-X rocket awaiting the approaching liftoff of its flight test. This is the first time since the Apollo Program's Saturn rockets were retired that a vehicle other than the space shuttle has occupied the pad. Part of the Constellation Program, the Ares I-X is the test vehicle for the Ares I. The Ares I-X flight test is set for Oct. 27. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Kim Shiflett

KSC-2009-5858

NASA Image and Video Library

2009-10-23

CAPE CANAVERAL, Fla. - As night settles over Launch Complex 39B at NASA's Kennedy Space Center in Florida, xenon lights reveal the Ares I-X rocket awaiting the approaching liftoff of its flight test. This is the first time since the Apollo Program's Saturn rockets were retired that a vehicle other than the space shuttle has occupied the pad. Part of the Constellation Program, the Ares I-X is the test vehicle for the Ares I. The Ares I-X flight test is set for Oct. 27. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Kim Shiflett

KSC-2009-5847

NASA Image and Video Library

2009-10-23

CAPE CANAVERAL, Fla. - As nightfall comes to Launch Complex 39B at NASA's Kennedy Space Center in Florida, xenon lights illuminate the pad and the Ares I-X rocket awaiting the approaching liftoff of its flight test. This is the first time since the Apollo Program's Saturn rockets were retired that a vehicle other than the space shuttle has occupied the pad. Part of the Constellation Program, the Ares I-X is the test vehicle for the Ares I. The Ares I-X flight test is set for Oct. 27. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Kim Shiflett

KSC-2009-5846

NASA Image and Video Library

2009-10-23

CAPE CANAVERAL, Fla. - As nightfall comes to Launch Complex 39B at NASA's Kennedy Space Center in Florida, xenon lights illuminate the pad and the Ares I-X rocket awaiting the approaching liftoff of its flight test. This is the first time since the Apollo Program's Saturn rockets were retired that a vehicle other than the space shuttle has occupied the pad. Part of the Constellation Program, the Ares I-X is the test vehicle for the Ares I. The Ares I-X flight test is set for Oct. 27. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Kim Shiflett

KSC-2009-5853

NASA Image and Video Library

2009-10-23

CAPE CANAVERAL, Fla. - As nightfall comes to Launch Complex 39B at NASA's Kennedy Space Center in Florida, xenon lights reveal the Ares I-X rocket awaiting the approaching liftoff of its flight test. This is the first time since the Apollo Program's Saturn rockets were retired that a vehicle other than the space shuttle has occupied the pad. Part of the Constellation Program, the Ares I-X is the test vehicle for the Ares I. The Ares I-X flight test is set for Oct. 27. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Kim Shiflett

KSC-2009-5854

NASA Image and Video Library

2009-10-23

CAPE CANAVERAL, Fla. - As nightfall comes to Launch Complex 39B at NASA's Kennedy Space Center in Florida, xenon lights reveal the Ares I-X rocket awaiting the approaching liftoff of its flight test. This is the first time since the Apollo Program's Saturn rockets were retired that a vehicle other than the space shuttle has occupied the pad. Part of the Constellation Program, the Ares I-X is the test vehicle for the Ares I. The Ares I-X flight test is set for Oct. 27. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Kim Shiflett

KSC-2009-5855

NASA Image and Video Library

2009-10-23

CAPE CANAVERAL, Fla. - As nightfall comes to Launch Complex 39B at NASA's Kennedy Space Center in Florida, xenon lights reveal the Ares I-X rocket awaiting the approaching liftoff of its flight test. This is the first time since the Apollo Program's Saturn rockets were retired that a vehicle other than the space shuttle has occupied the pad. Part of the Constellation Program, the Ares I-X is the test vehicle for the Ares I. The Ares I-X flight test is set for Oct. 27. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Kim Shiflett

KSC-2009-5856

NASA Image and Video Library

2009-10-23

CAPE CANAVERAL, Fla. - As night settles over Launch Complex 39B at NASA's Kennedy Space Center in Florida, xenon lights reveal the Ares I-X rocket awaiting the approaching liftoff of its flight test. This is the first time since the Apollo Program's Saturn rockets were retired that a vehicle other than the space shuttle has occupied the pad. Part of the Constellation Program, the Ares I-X is the test vehicle for the Ares I. The Ares I-X flight test is set for Oct. 27. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Kim Shiflett

KSC-2009-5851

NASA Image and Video Library

2009-10-23

CAPE CANAVERAL, Fla. - As nightfall comes to Launch Complex 39B at NASA's Kennedy Space Center in Florida, xenon lights reveal the Ares I-X rocket awaiting the approaching liftoff of its flight test. This is the first time since the Apollo Program's Saturn rockets were retired that a vehicle other than the space shuttle has occupied the pad. Part of the Constellation Program, the Ares I-X is the test vehicle for the Ares I. The Ares I-X flight test is set for Oct. 27. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Kim Shiflett

KSC-2009-5857

NASA Image and Video Library

2009-10-23

CAPE CANAVERAL, Fla. - As night settles over Launch Complex 39B at NASA's Kennedy Space Center in Florida, xenon lights reveal the Ares I-X rocket awaiting the approaching liftoff of its flight test. This is the first time since the Apollo Program's Saturn rockets were retired that a vehicle other than the space shuttle has occupied the pad. Part of the Constellation Program, the Ares I-X is the test vehicle for the Ares I. The Ares I-X flight test is set for Oct. 27. For information on the Ares I-X vehicle and flight test, visit http://www.nasa.gov/aresIX. Photo credit: NASA/Kim Shiflett

Full-Scaled Advanced Systems Testbed: Ensuring Success of Adaptive Control Research Through Project Lifecycle Risk Mitigation

NASA Technical Reports Server (NTRS)

Pavlock, Kate M.

2011-01-01

The National Aeronautics and Space Administration's Dryden Flight Research Center completed flight testing of adaptive controls research on the Full-Scale Advance Systems Testbed (FAST) in January of 2011. The research addressed technical challenges involved with reducing risk in an increasingly complex and dynamic national airspace. Specific challenges lie with the development of validated, multidisciplinary, integrated aircraft control design tools and techniques to enable safe flight in the presence of adverse conditions such as structural damage, control surface failures, or aerodynamic upsets. The testbed is an F-18 aircraft serving as a full-scale vehicle to test and validate adaptive flight control research and lends a significant confidence to the development, maturation, and acceptance process of incorporating adaptive control laws into follow-on research and the operational environment. The experimental systems integrated into FAST were designed to allow for flexible yet safe flight test evaluation and validation of modern adaptive control technologies and revolve around two major hardware upgrades: the modification of Production Support Flight Control Computers (PSFCC) and integration of two, fourth-generation Airborne Research Test Systems (ARTS). Post-hardware integration verification and validation provided the foundation for safe flight test of Nonlinear Dynamic Inversion and Model Reference Aircraft Control adaptive control law experiments. To ensure success of flight in terms of cost, schedule, and test results, emphasis on risk management was incorporated into early stages of design and flight test planning and continued through the execution of each flight test mission. Specific consideration was made to incorporate safety features within the hardware and software to alleviate user demands as well as into test processes and training to reduce human factor impacts to safe and successful flight test. This paper describes the research configuration, experiment functionality, overall risk mitigation, flight test approach and results, and lessons learned of adaptive controls research of the Full-Scale Advanced Systems Testbed.

Dream Chaser ALT-2 Free Flight

NASA Image and Video Library

2017-11-11

Sierra Nevada Corp’s Dream Chaser being towed from the former space shuttle hangar at NASA Armstrong Flight Research Center in California where it was housed and prepared for its successful Nov. 11, 2017 approach and landing test.

Modular Infrastructure for Rapid Flight Software Development

NASA Technical Reports Server (NTRS)

Pires, Craig

2010-01-01

This slide presentation reviews the use of modular infrastructure to assist in the development of flight software. A feature of this program is the use of model based approach for application unique software. A review of two programs that this approach was use on are: the development of software for Hover Test Vehicle (HTV), and Lunar Atmosphere and Dust Environment Experiment (LADEE).

Results from a GPS Shuttle Training Aircraft flight test

NASA Technical Reports Server (NTRS)

Saunders, Penny E.; Montez, Moises N.; Robel, Michael C.; Feuerstein, David N.; Aerni, Mike E.; Sangchat, S.; Rater, Lon M.; Cryan, Scott P.; Salazar, Lydia R.; Leach, Mark P.

1991-01-01

A series of Global Positioning System (GPS) flight tests were performed on a National Aeronautics and Space Administration's (NASA's) Shuttle Training Aircraft (STA). The objective of the tests was to evaluate the performance of GPS-based navigation during simulated Shuttle approach and landings for possible replacement of the current Shuttle landing navigation aid, the Microwave Scanning Beam Landing System (MSBLS). In particular, varying levels of sensor data integration would be evaluated to determine the minimum amount of integration required to meet the navigation accuracy requirements for a Shuttle landing. Four flight tests consisting of 8 to 9 simulation runs per flight test were performed at White Sands Space Harbor in April 1991. Three different GPS receivers were tested. The STA inertial navigation, tactical air navigation, and MSBLS sensor data were also recorded during each run. C-band radar aided laser trackers were utilized to provide the STA 'truth' trajectory.

Automatic treatment of flight test images using modern tools: SAAB and Aeritalia joint approach

NASA Astrophysics Data System (ADS)

Kaelldahl, A.; Duranti, P.

The use of onboard cine cameras, as well as that of on ground cinetheodolites, is very popular in flight tests. The high resolution of film and the high frame rate of cinecameras are still not exceeded by video technology. Video technology can successfully enter the flight test scenario once the availability of solid-state optical sensors dramatically reduces the dimensions, and weight of TV cameras, thus allowing to locate them in positions compatible with space or operational limitations (e.g., HUD cameras). A proper combination of cine and video cameras is the typical solution for a complex flight test program. The output of such devices is very helpful in many flight areas. Several sucessful applications of this technology are summarized. Analysis of the large amount of data produced (frames of images) requires a very long time. The analysis is normally carried out manually. In order to improve the situation, in the last few years, several flight test centers have devoted their attention to possible techniques which allow for quicker and more effective image treatment.

Development and evaluation of an airplane electronic display format aligned with the inertial velocity vector

NASA Technical Reports Server (NTRS)

Steinmetz, G. G.

1986-01-01

The development of an electronic primary flight display format aligned with the aircraft velocity vector, a simulation evaluation comparing this format with an electronic attitude-aligned primary flight display format, and a flight evaluation of the velocity-vector-aligned display format are described. Earlier tests in turbulent conditions with the electronic attitude-aligned display format had exhibited unsteadiness. A primary objective of aligning the display format with the velocity vector was to take advantage of a velocity-vector control-wheel steering system to provide steadiness of display during turbulent conditions. Better situational awareness under crosswind conditions was also achieved. The evaluation task was a curved, descending approach with turbulent and crosswind conditions. Primary flight display formats contained computer-drawn perspective runway images and flight-path angle information. The flight tests were conducted aboard the NASA Transport Systems Research Vehicle (TSRV). Comparative results of the simulation and flight tests were principally obtained from subjective commentary. Overall, the pilots preferred the display format aligned with the velocity vector.

A U.S. Army CH-47 Chinook helicopter slowly lowers the X-40 sub-scale technology demonstrator to the ground under the watchful eyes of ground crew at the conclusion of a captive-carry test flight

NASA Image and Video Library

2000-12-08

A U.S. Army CH-47 Chinook helicopter slowly lowers the X-40 sub-scale technology demonstrator to the ground under the watchful eyes of ground crew at the conclusion of a captive-carry test flight at NASA's Dryden Flight Research Center, Edwards, California. Several captive-carry flights were conducted to check out all operating systems and procedures before the X-40 made its first free flight at Edwards, gliding to a fully-autonomous approach and landing on the Edwards runway. The X-40 is an unpowered 82 percent scale version of the X-37, a Boeing-developed spaceplane designed to demonstrate various advanced technologies for development of future lower-cost access to space vehicles. Flight tests of the X-40 are designed to reduce the risks associated with research flights of the larger, more complex X-37.

Flight testing of a luminescent surface pressure sensor

NASA Technical Reports Server (NTRS)

Mclachlan, B. G.; Bell, J. H.; Espina, J.; Gallery, J.; Gouterman, M.; Demandante, C. G. N.; Bjarke, L.

1992-01-01

NASA ARC has conducted flight tests of a new type of aerodynamic pressure sensor based on a luminescent surface coating. Flights were conducted at the NASA ARC-Dryden Flight Research Facility. The luminescent pressure sensor is based on a surface coating which, when illuminated with ultraviolet light, emits visible light with an intensity dependent on the local air pressure on the surface. This technique makes it possible to obtain pressure data over the entire surface of an aircraft, as opposed to conventional instrumentation, which can only make measurements at pre-selected points. The objective of the flight tests was to evaluate the effectiveness and practicality of a luminescent pressure sensor in the actual flight environment. A luminescent pressure sensor was installed on a fin, the Flight Test Fixture (FTF), that is attached to the underside of an F-104 aircraft. The response of one particular surface coating was evaluated at low supersonic Mach numbers (M = 1.0-1.6) in order to provide an initial estimate of the sensor's capabilities. This memo describes the test approach, the techniques used, and the pressure sensor's behavior under flight conditions. A direct comparison between data provided by the luminescent pressure sensor and that produced by conventional pressure instrumentation shows that the luminescent sensor can provide quantitative data under flight conditions. However, the test results also show that the sensor has a number of limitations which must be addressed if this technique is to prove useful in the flight environment.

5-inch-size liquid crystal flat panel display evaluation test by flight simulator

NASA Astrophysics Data System (ADS)

Kawahara, Hiroyasu; Watanabe, Akira; Wakairo, Kaoru; Udagawa, Tomoyuki; Kurihara, Yoichiro

An evaluation test is conducted on the function, performance, and display format of a 5x5 inch flat panel display (FPD) in a flight simulator. The FPD utilizes a color liquid crystal panel that is compact and lightweight and has excellent visibility. The simulator evaluation test is carried out in sequence with the conventional takeoff and landing to altitude, and then conversion to STOL procedures for flight path and subsequent approach and landing. It is shown that the liquid crystal display could be employed as a satisfactory indicator for aircraft instrumentation.

Hypersonic technology-approach to an expanded program

NASA Technical Reports Server (NTRS)

Hearth, D. P.; Preyss, A. E.

1976-01-01

An overview of research, testing, and technology in the hypersonic range. Military and civilian hypersonic flight systems envisaged, ground testing facilities under development, methods for cooling the heated airframe, and use of hydrogen as fuel and coolant are discussed extensively. Air-breathing hypersonic cruise systems are emphasized, the airframe-integrated scramjet configuration is discussed and illustrated, materials proposed for hypersonic vehicles are reviewed, and test results on hypersonic flight (X-15 research aircraft) are indicated. Major advances and major problems in hypersonic flight and hypersonic technology are outlined, and the need for a hypersonic flying-laboratory research craft is stressed.

Flight-testing and frequency-domain analysis for rotorcraft handling qualities

NASA Technical Reports Server (NTRS)

Ham, Johnnie A.; Gardner, Charles K.; Tischler, Mark B.

1995-01-01

A demonstration of frequency-domain flight-testing techniques and analysis was performed on a U.S. Army OH-58D helicopter in support of the OH-58D Airworthiness and Flight Characteristics Evaluation and of the Army's development and ongoing review of Aeronautical Design Standard 33C, Handling Qualities Requirements for Military Rotorcraft. Hover and forward flight (60 kn) tests were conducted in 1 flight hour by Army experimental test pilots. Further processing of the hover data generated a complete database of velocity, angular-rate, and acceleration-frequency responses to control inputs. A joint effort was then undertaken by the Airworthiness Qualification Test Dirtectorate and the U.S. Army Aeroflightdynamics Directorate to derive handling-quality information from the frequency-domain database using a variety of approaches. This report documents numerous results that have been obtained from the simple frequency-domain tests; in many areas, these results provide more insight into the aircraft dynmamics that affect handling qualities than do traditional flight tests. The handling-quality results include ADS-33C bandwidth and phase-delay calculations, vibration spectral determinations, transfer-function models to examine single-axis results, and a six-degree-of-freedom fully coupled state-space model. The ability of this model to accurately predict responses was verified using data from pulse inputs. This report also documents the frequency-sweep flight-test technique and data analysis used to support the tests.

F-15B QuietSpike(TradeMark) Aeroservoelastic Flight Test Data Analysis

NASA Technical Reports Server (NTRS)

Kukreja, Sunil L.

2007-01-01

System identification or mathematical modelling is utilised in the aerospace community for the development of simulation models for robust control law design. These models are often described as linear, time-invariant processes and assumed to be uniform throughout the flight envelope. Nevertheless, it is well known that the underlying process is inherently nonlinear. The reason for utilising a linear approach has been due to the lack of a proper set of tools for the identification of nonlinear systems. Over the past several decades the controls and biomedical communities have made great advances in developing tools for the identification of nonlinear systems. These approaches are robust and readily applicable to aerospace systems. In this paper, we show the application of one such nonlinear system identification technique, structure detection, for the analysis of F-15B QuietSpike(TradeMark) aeroservoelastic flight test data. Structure detection is concerned with the selection of a subset of candidate terms that best describe the observed output. This is a necessary procedure to compute an efficient system description which may afford greater insight into the functionality of the system or a simpler controller design. Structure computation as a tool for black-box modelling may be of critical importance for the development of robust, parsimonious models for the flight-test community. Moreover, this approach may lead to efficient strategies for rapid envelope expansion which may save significant development time and costs. The objectives of this study are to demonstrate via analysis of F-15B QuietSpike(TradeMark) aeroservoelastic flight test data for several flight conditions (Mach number) that (i) linear models are inefficient for modelling aeroservoelastic data, (ii) nonlinear identification provides a parsimonious model description whilst providing a high percent fit for cross-validated data and (iii) the model structure and parameters vary as the flight condition is altered.

Control Oriented Modeling and Validation of Aeroservoelastic Systems

NASA Technical Reports Server (NTRS)

Crowder, Marianne; deCallafon, Raymond (Principal Investigator)

2002-01-01

Lightweight aircraft design emphasizes the reduction of structural weight to maximize aircraft efficiency and agility at the cost of increasing the likelihood of structural dynamic instabilities. To ensure flight safety, extensive flight testing and active structural servo control strategies are required to explore and expand the boundary of the flight envelope. Aeroservoelastic (ASE) models can provide online flight monitoring of dynamic instabilities to reduce flight time testing and increase flight safety. The success of ASE models is determined by the ability to take into account varying flight conditions and the possibility to perform flight monitoring under the presence of active structural servo control strategies. In this continued study, these aspects are addressed by developing specific methodologies and algorithms for control relevant robust identification and model validation of aeroservoelastic structures. The closed-loop model robust identification and model validation are based on a fractional model approach where the model uncertainties are characterized in a closed-loop relevant way.

Development and flight test experiences with a flight-crucial digital control system

NASA Technical Reports Server (NTRS)

Mackall, Dale A.

1988-01-01

Engineers and scientists in the advanced fighter technology integration (AFTI) F-16 program investigated the integration of emerging technologies into an advanced fighter aircraft. AFTI's three major technologies included: flight-crucial digital control, decoupled aircraft flight control, and integration of avionics, flight control, and pilot displays. In addition to investigating improvements in fighter performance, researchers studied the generic problems confronting the designers of highly integrated flight-crucial digital control. An overview is provided of both the advantages and problems of integration digital control systems. Also, an examination of the specification, design, qualification, and flight test life-cycle phase is provided. An overview is given of the fault-tolerant design, multimoded decoupled flight control laws, and integrated avionics design. The approach to qualifying the software and system designs is discussed, and the effects of design choices on system qualification are highlighted.

Guidance, Navigation and Control (GN and C) Design Overview and Flight Test Results from NASA's Max Launch Abort System (MLAS)

NASA Technical Reports Server (NTRS)

Dennehy, Cornelius J.; Lanzi, Raymond J.; Ward, Philip R.

2010-01-01

The National Aeronautics and Space Administration Engineering and Safety Center designed, developed and flew the alternative Max Launch Abort System (MLAS) as risk mitigation for the baseline Orion spacecraft launch abort system already in development. The NESC was tasked with both formulating a conceptual objective system design of this alternative MLAS as well as demonstrating this concept with a simulated pad abort flight test. Less than 2 years after Project start the MLAS simulated pad abort flight test was successfully conducted from Wallops Island on July 8, 2009. The entire flight test duration was 88 seconds during which time multiple staging events were performed and nine separate critically timed parachute deployments occurred as scheduled. This paper provides an overview of the guidance navigation and control technical approaches employed on this rapid prototyping activity; describes the methodology used to design the MLAS flight test vehicle; and lessons that were learned during this rapid prototyping project are also summarized.

Testing Strategies and Methodologies for the Max Launch Abort System

NASA Technical Reports Server (NTRS)

Schaible, Dawn M.; Yuchnovicz, Daniel E.

2011-01-01

The National Aeronautics and Space Administration (NASA) Engineering and Safety Center (NESC) was tasked to develop an alternate, tower-less launch abort system (LAS) as risk mitigation for the Orion Project. The successful pad abort flight demonstration test in July 2009 of the "Max" launch abort system (MLAS) provided data critical to the design of future LASs, while demonstrating the Agency s ability to rapidly design, build and fly full-scale hardware at minimal cost in a "virtual" work environment. Limited funding and an aggressive schedule presented a challenge for testing of the complex MLAS system. The successful pad abort flight demonstration test was attributed to the project s systems engineering and integration process, which included: a concise definition of, and an adherence to, flight test objectives; a solid operational concept; well defined performance requirements, and a test program tailored to reducing the highest flight test risks. The testing ranged from wind tunnel validation of computational fluid dynamic simulations to component ground tests of the highest risk subsystems. This paper provides an overview of the testing/risk management approach and methodologies used to understand and reduce the areas of highest risk - resulting in a successful flight demonstration test.

ARC-1959-A-24953

NASA Image and Video Library

1959-03-19

Lockheed JF-104A (AF56-745A Tail No. 60745) Starfighter airplane piloted by Fred Drinkwater conducted flight testing that demonstrated steep approaches that were ultimately used by the space shuttle. Steep descent testing, including power-off landing approaches and demonstration of minimum lift-to-drag ratio (L/D) landings came out of the interest in the use of low L/D lifting bodies for recovery to landing from space. Note: Used in publication in Flight Research at Ames; 57 Years of Development and Validation of Aeronautical Technology NASA SP-1998-3300 fig 93

Description of a Computer Program Written for Approach and Landing Test Post Flight Data Extraction of Proximity Separation Aerodynamic Coefficients and Aerodynamic Data Base Verification

NASA Technical Reports Server (NTRS)

Homan, D. J.

1977-01-01

A computer program written to calculate the proximity aerodynamic force and moment coefficients of the Orbiter/Shuttle Carrier Aircraft (SCA) vehicles based on flight instrumentation is described. The ground reduced aerodynamic coefficients and instrumentation errors (GRACIE) program was developed as a tool to aid in flight test verification of the Orbiter/SCA separation aerodynamic data base. The program calculates the force and moment coefficients of each vehicle in proximity to the other, using the load measurement system data, flight instrumentation data and the vehicle mass properties. The uncertainty in each coefficient is determined, based on the quoted instrumentation accuracies. A subroutine manipulates the Orbiter/747 Carrier Separation Aerodynamic Data Book to calculate a comparable set of predicted coefficients for comparison to the calculated flight test data.

KSC-2014-3685

NASA Image and Video Library

2014-08-04

CAPE CANAVERAL, Fla. – All three of the United Launch Alliance, or ULA, Delta IV boosters for Exploration Flight Test-1 are in view inside the Horizontal Integration Facility at Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida. The port booster is being mated to the core booster. The ULA Delta IV Heavy rocket will launch an uncrewed Orion spacecraft on Exploration Flight Test-1. During the mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Ben Smegelsky

KSC-2014-3686

NASA Image and Video Library

2014-08-04

CAPE CANAVERAL, Fla. – All three of the United Launch Alliance, or ULA, Delta IV boosters for Exploration Flight Test-1 are in view inside the Horizontal Integration Facility at Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida. The port booster is being mated to the core booster. The ULA Delta IV Heavy rocket will launch an uncrewed Orion spacecraft on Exploration Flight Test-1. During the mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Ben Smegelsky

KSC-2014-4161

NASA Image and Video Library

2014-09-30

CAPE CANAVERAL, Fla. – Inside the Horizontal Integration Facility at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida, United Launch Alliance technicians and engineers prepare the Delta IV Heavy rocket for rollout to the pad. The rocket is secured on the Elevated Platform Transporter for the trip to the pad. The Delta IV Heavy will launch Orion on Exploration Flight Test-1. During its first flight test, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Dimitri Gerondidakis

A flight investigation of simulated data-link communications during single-pilot IFR flight. Volume 1: Experimental design and initial test

NASA Technical Reports Server (NTRS)

Parker, J. F., Jr.; Duffy, J. W.; Christensen, D. G.

1981-01-01

A Flight Data Console simulation of a digital communication link to replace the current voice communication system used in air traffic control (ATC) was developed. The study determined how a digital communications system reduces cockpit workload, improve, flight proficiency, and is acceptable to general aviation pilots. It is shown that instrument flight, including approach and landing, can be accomplished by using a digital data link system for ATC communication.

The calibration and flight test performance of the space shuttle orbiter air data system

NASA Technical Reports Server (NTRS)

Dean, A. S.; Mena, A. L.

1983-01-01

The Space Shuttle air data system (ADS) is used by the guidance, navigation and control system (GN&C) to guide the vehicle to a safe landing. In addition, postflight aerodynamic analysis requires a precise knowledge of flight conditions. Since the orbiter is essentially an unpowered vehicle, the conventional methods of obtaining the ADS calibration were not available; therefore, the calibration was derived using a unique and extensive wind tunnel test program. This test program included subsonic tests with a 0.36-scale orbiter model, transonic and supersonic tests with a smaller 0.2-scale model, and numerous ADS probe-alone tests. The wind tunnel calibration was further refined with subsonic results from the approach and landing test (ALT) program, thus producing the ADS calibration for the orbital flight test (OFT) program. The calibration of the Space Shuttle ADS and its performance during flight are discussed in this paper. A brief description of the system is followed by a discussion of the calibration methodology, and then by a review of the wind tunnel and flight test programs. Finally, the flight results are presented, including an evaluation of the system performance for on-board systems use and a description of the calibration refinements developed to provide the best possible air data for postflight analysis work.

Shuttle payload vibroacoustic test plan evaluation

NASA Technical Reports Server (NTRS)

Stahle, C. V.; Gongloff, H. R.; Young, J. P.; Keegan, W. B.

1977-01-01

Statistical decision theory is used to evaluate seven alternate vibro-acoustic test plans for Space Shuttle payloads; test plans include component, subassembly and payload testing and combinations of component and assembly testing. The optimum test levels and the expected cost are determined for each test plan. By including all of the direct cost associated with each test plan and the probabilistic costs due to ground test and flight failures, the test plans which minimize project cost are determined. The lowest cost approach eliminates component testing and maintains flight vibration reliability by performing subassembly tests at a relatively high acoustic level.

Dream Chaser ALT-2 Free Flight

NASA Image and Video Library

2017-11-11

Sierra Nevada Corp’s Dream Chaser crew attached the wires that the helicopter would use to pick it up from NASA’s Armstrong Flight Research Center in California in preparation for its successful approach and landing test Nov. 11, 2017.

Dream Chaser ALT-2 Free Flight

NASA Image and Video Library

2017-11-07

A lift device was attached to Sierra Nevada Corp’s Dream Chaser for a helicopter to pick it up to drop for its successful approach and landing test at NASA’s Armstrong Flight Research Center in California on Nov. 11, 2017.

Approach for Structurally Clearing an Adaptive Compliant Trailing Edge Flap for Flight

NASA Technical Reports Server (NTRS)

Miller, Eric J.; Lokos, William A.; Cruz, Josue; Crampton, Glen; Stephens, Craig A.; Kota, Sridhar; Ervin, Gregory; Flick, Pete

2015-01-01

The Adaptive Compliant Trailing Edge (ACTE) flap was flown on the NASA Gulfstream GIII test bed at the NASA Armstrong Flight Research Center. This smoothly curving flap replaced the existing Fowler flaps creating a seamless control surface. This compliant structure, developed by FlexSys Inc. in partnership with Air Force Research Laboratory, supported NASA objectives for airframe structural noise reduction, aerodynamic efficiency, and wing weight reduction through gust load alleviation. A thorough structures airworthiness approach was developed to move this project safely to flight.

Analyses of shuttle orbiter approach and landing conditions

NASA Technical Reports Server (NTRS)

Teper, G. L.; Dimarco, R. J.; Ashkenas, I. L.; Hoh, R. H.

1981-01-01

A study of one shuttle orbiter approach and landing conditions are summarized. Causes of observed PIO like flight deficiencies are identified and potential cures are examined. Closed loop pilot/vehicle analyses are described and path/attitude stability boundaries defined. The latter novel technique proved of great value in delineating and illustrating the basic causes of this multiloop pilot control problem. The analytical results are shown to be consistent with flight test and fixed base simulation. Conclusions are drawn relating to possible improvements of the shuttle orbiter/digital flight control system.

Differential GPS/inertial navigation approach/landing flight test results

NASA Technical Reports Server (NTRS)

Snyder, Scott; Schipper, Brian; Vallot, Larry; Parker, Nigel; Spitzer, Cary

1992-01-01

Results of a joint Honeywell/NASA-Langley differential GPS/inertial flight test conducted in November 1990 are discussed focusing on postflight data analysis. The test was aimed at acquiring a system performance database and demonstrating automatic landing based on an integrated differential GPS/INS with barometric and radar altimeters. Particular attention is given to characteristics of DGPS/inertial error and the magnitude of the differential corrections and vertical channel performance with and without altimeter augmentation. It is shown that DGPS/inertial integrated with a radar altimeter is capable of providing a precision approach and autoland guidance of manned return space vehicles within the Space Shuttle accuracy requirements.

The Charlotte (TM) intra-vehicular robot

NASA Technical Reports Server (NTRS)

Swaim, Patrick L.; Thompson, Clark J.; Campbell, Perry D.

1994-01-01

NASA has identified telerobotics and telescience as essential technologies to reduce the crew extra-vehicular activity (EVA) and intra-vehicular activity (IVA) workloads. Under this project, we are developing and flight testing a novel IVA robot to relieve the crew of tedious and routine tasks. Through ground telerobotic control of this robot, we will enable ground researchers to routinely interact with experiments in space. Our approach is to develop an IVA robot system incrementally by employing a series of flight tests with increasing complexity. This approach has the advantages of providing an early IVA capability that can assist the crew, demonstrate capabilities that ground researchers can be confident of in planning for future experiments, and allow incremental refinement of system capabilities and insertion of new technology. In parallel with this approach to flight testing, we seek to establish ground test beds, in which the requirements of payload experimenters can be further investigated. In 1993 we reviewed manifested SpaceHab experiments and defined IVA robot requirements to assist in their operation. We also examined previous IVA robot designs and assessed them against flight requirements. We rejected previous design concepts on the basis of threat to crew safety, operability, and maintainability. Based on this insight, we developed an entirely new concept for IVA robotics, the CHARLOTTE robot system. Ground based testing of a prototype version of the system has already proven its ability to perform most common tasks demanded of the crew, including operation of switches, buttons, knobs, dials, and performing video surveys of experiments and switch panels.

GN and C Design Overview and Flight Test Results from NASA's Max Launch Abort System (MLAS)

NASA Technical Reports Server (NTRS)

Dennehy, Cornelius J.; Lanzi, Ryamond J.; Ward, Philip R.

2010-01-01

The National Aeronautics and Space Administration (NASA) Engineering and Safety Center (NESC) designed, developed and flew the alternative Max Launch Abort System (MLAS) as risk mitigation for the baseline Orion spacecraft launch abort system (LAS) already in development. The NESC was tasked with both formulating a conceptual objective system (OS) design of this alternative MLAS as well as demonstrating this concept with a simulated pad abort flight test. The goal was to obtain sufficient flight test data to assess performance, validate models/tools, and to reduce the design and development risks for a MLAS OS. Less than 2 years after Project start the MLAS simulated pad abort flight test was successfully conducted from Wallops Island on July 8, 2009. The entire flight test duration was 88 seconds during which time multiple staging events were performed and nine separate critically timed parachute deployments occurred as scheduled. Overall, the as-flown flight performance was as predicted prior to launch. This paper provides an overview of the guidance navigation and control (GN&C) technical approaches employed on this rapid prototyping activity. This paper describes the methodology used to design the MLAS flight test vehicle (FTV). Lessons that were learned during this rapid prototyping project are also summarized.

APPROACH & LANDING TEST (ALT) - SHUTTLE PATCH

NASA Image and Video Library

1976-11-01

S76-30340 (1976) --- This circular, red, white and blue emblem has been chosen as the official insignia for the Space Shuttle Approach and Landing Test (ALT) flights. A picture of the Orbiter 101 "Enterprise" is superimposed over a red triangle, which in turn is superimposed over a large inner circle of dark blue. The surnames of the members of the two ALT crews are in white in the field of blue. The four crew men are astronauts Fred W. Haise Jr., commander of the first crew; Joe H. Engle, commander of the second crew; and Richard H. Truly, pilot of the second crew. ALT is a series of flights with a modified Boeing 747 Shuttle Carrier Aircraft (SCA) as a ferry aircraft and airborne launch platform for the 67,300 kilogram (75-ton) "Enterprise". The Shuttle Orbiter atmospheric testing is in preparation for the first Earth-orbital flights scheduled in 1979.

Architecture-Based Unit Testing of the Flight Software Product Line

NASA Technical Reports Server (NTRS)

Ganesan, Dharmalingam; Lindvall, Mikael; McComas, David; Bartholomew, Maureen; Slegel, Steve; Medina, Barbara

2010-01-01

This paper presents an analysis of the unit testing approach developed and used by the Core Flight Software (CFS) product line team at the NASA GSFC. The goal of the analysis is to understand, review, and reconunend strategies for improving the existing unit testing infrastructure as well as to capture lessons learned and best practices that can be used by other product line teams for their unit testing. The CFS unit testing framework is designed and implemented as a set of variation points, and thus testing support is built into the product line architecture. The analysis found that the CFS unit testing approach has many practical and good solutions that are worth considering when deciding how to design the testing architecture for a product line, which are documented in this paper along with some suggested innprovennents.

A Turbine-powered UAV Controls Testbed

NASA Technical Reports Server (NTRS)

Motter, Mark A.; High, James W.; Guerreiro, Nelson M.; Chambers, Ryan S.; Howard, Keith D.

2007-01-01

The latest version of the NASA Flying Controls Testbed (FLiC) integrates commercial-off-the-shelf components including airframe, autopilot, and a small turbine engine to provide a low cost experimental flight controls testbed capable of sustained speeds up to 200 mph. The series of flight tests leading up to the demonstrated performance of the vehicle in sustained, autopiloted 200 mph flight at NASA Wallops Flight Facility's UAV runway in August 2006 will be described. Earlier versions of the FLiC were based on a modified Army target drone, AN/FQM-117B, developed as part of a collaboration between the Aviation Applied Technology Directorate at Fort Eustis, Virginia and NASA Langley Research Center. The newer turbine powered platform (J-FLiC) builds on the successes using the relatively smaller, slower and less expensive unmanned aerial vehicle developed specifically to test highly experimental flight control approaches with the implementation of C-coded experimental controllers. Tracking video was taken during the test flights at Wallops and will be available for presentation at the conference. Analysis of flight data from both remotely piloted and autopiloted flights will be presented. Candidate experimental controllers for implementation will be discussed. It is anticipated that flight testing will resume in Spring 2007 and those results will be included, if possible.

Spacecraft attitude control using a smart control system

NASA Technical Reports Server (NTRS)

Buckley, Brian; Wheatcraft, Louis

1992-01-01

Traditionally, spacecraft attitude control has been implemented using control loops written in native code for a space hardened processor. The Naval Research Lab has taken this approach during the development of the Attitude Control Electronics (ACE) package. After the system was developed and delivered, NRL decided to explore alternate technologies to accomplish this same task more efficiently. The approach taken by NRL was to implement the ACE control loops using systems technologies. The purpose of this effort was to: (1) research capabilities required of an expert system in processing a classic closed-loop control algorithm; (2) research the development environment required to design and test an embedded expert systems environment; (3) research the complexity of design and development of expert systems versus a conventional approach; and (4) test the resulting systems against the flight acceptance test software for both response and accuracy. Two expert systems were selected to implement the control loops. Criteria used for the selection of the expert systems included that they had to run in both embedded systems and ground based environments. Using two different expert systems allowed a comparison of the real-time capabilities, inferencing capabilities, and the ground-based development environment. The two expert systems chosen for the evaluation were Spacecraft Command Language (SCL), and NEXTPERT Object. SCL is a smart control system produced for the NRL by Interface and Control Systems (ICS). SCL was developed to be used for real-time command, control, and monitoring of a new generation of spacecraft. NEXPERT Object is a commercially available product developed by Neuron Data. Results of the effort were evaluated using the ACE test bed. The ACE test bed had been developed and used to test the original flight hardware and software using simulators and flight-like interfaces. The test bed was used for testing the expert systems in a 'near-flight' environment. The technical approach, the system architecture, the development environments, knowledge base development, and results of this effort are detailed.

An improved approach for flight readiness certification: Methodology for failure risk assessment and application examples. Volume 2: Software documentation

NASA Technical Reports Server (NTRS)

Moore, N. R.; Ebbeler, D. H.; Newlin, L. E.; Sutharshana, S.; Creager, M.

1992-01-01

An improved methodology for quantitatively evaluating failure risk of spaceflight systems to assess flight readiness and identify risk control measures is presented. This methodology, called Probabilistic Failure Assessment (PFA), combines operating experience from tests and flights with engineering analysis to estimate failure risk. The PFA methodology is of particular value when information on which to base an assessment of failure risk, including test experience and knowledge of parameters used in engineering analyses of failure phenomena, is expensive or difficult to acquire. The PFA methodology is a prescribed statistical structure in which engineering analysis models that characterize failure phenomena are used conjointly with uncertainties about analysis parameters and/or modeling accuracy to estimate failure probability distributions for specific failure modes, These distributions can then be modified, by means of statistical procedures of the PFA methodology, to reflect any test or flight experience. Conventional engineering analysis models currently employed for design of failure prediction are used in this methodology. The PFA methodology is described and examples of its application are presented. Conventional approaches to failure risk evaluation for spaceflight systems are discussed, and the rationale for the approach taken in the PFA methodology is presented. The statistical methods, engineering models, and computer software used in fatigue failure mode applications are thoroughly documented.

An improved approach for flight readiness certification: Methodology for failure risk assessment and application examples, volume 1

NASA Technical Reports Server (NTRS)

Moore, N. R.; Ebbeler, D. H.; Newlin, L. E.; Sutharshana, S.; Creager, M.

1992-01-01

An improved methodology for quantitatively evaluating failure risk of spaceflight systems to assess flight readiness and identify risk control measures is presented. This methodology, called Probabilistic Failure Assessment (PFA), combines operating experience from tests and flights with engineering analysis to estimate failure risk. The PFA methodology is of particular value when information on which to base an assessment of failure risk, including test experience and knowledge of parameters used in engineering analyses of failure phenomena, is expensive or difficult to acquire. The PFA methodology is a prescribed statistical structure in which engineering analysis models that characterize failure phenomena are used conjointly with uncertainties about analysis parameters and/or modeling accuracy to estimate failure probability distributions for specific failure modes. These distributions can then be modified, by means of statistical procedures of the PFA methodology, to reflect any test or flight experience. Conventional engineering analysis models currently employed for design of failure prediction are used in this methodology. The PFA methodology is described and examples of its application are presented. Conventional approaches to failure risk evaluation for spaceflight systems are discussed, and the rationale for the approach taken in the PFA methodology is presented. The statistical methods, engineering models, and computer software used in fatigue failure mode applications are thoroughly documented.

KSC-07pd0887

NASA Image and Video Library

2007-04-16

KENNEDY SPACE CENTER, FLA. -- A Starfighter F-104 piloted by Rick Svetkoff approaches the Shuttle Landing Facility at Kennedy Space Center. The aircraft will take part in a series of pathfinder test missions from the space shuttle runway. Two flights will generate test data to validate sonic boom assumptions about the potential impacts of suborbital and orbital commercial spaceflight from the facility. NASA is assessing the environmental impact of such flights. Starfighters Inc. of Clearwater, Fla., will perform the flights to help in assessing suborbital space launch trajectories from the runway and paving the way for future commercial space tourism and research flights from the facility. Photo credit: NASA/Kim Shiflett

In-house experiments in large space structures at the Air Force Wright Aeronautical Laboratories Flight Dynamics Laboratory

NASA Technical Reports Server (NTRS)

Gordon, Robert W.; Ozguner, Umit; Yurkovich, Steven

1989-01-01

The Flight Dynamics Laboratory is committed to an in-house, experimental investigation of several technical areas critical to the dynamic performance of future Air Force large space structures. The advanced beam experiment was successfully completed and provided much experience in the implementation of active control approaches on real hardware. A series of experiments is under way in evaluating ground test methods on the 12 meter trusses with significant passive damping. Ground simulated zero-g response data from the undamped truss will be compared directly with true zero-g flight test data. The performance of several leading active control approaches will be measured and compared on one of the trusses in the presence of significant passive damping. In the future, the PACOSS dynamic test article will be set up as a test bed for the evaluation of system identification and control techniques on a complex, representative structure with high modal density and significant passive damping.

Unsteady Aerodynamic Model Tuning for Precise Flutter Prediction

NASA Technical Reports Server (NTRS)

Pak, Chan-Gi

2011-01-01

A simple method for an unsteady aerodynamic model tuning is proposed in this study. This method is based on the direct modification of the aerodynamic influence coefficient matrices. The aerostructures test wing 2 flight-test data is used to demonstrate the proposed model tuning method. The flutter speed margin computed using only the test validated structural dynamic model can be improved using the additional unsteady aerodynamic model tuning, and then the flutter speed margin requirement of 15 % in military specifications can apply towards the test validated aeroelastic model. In this study, unsteady aerodynamic model tunings are performed at two time invariant flight conditions, at Mach numbers of 0.390 and 0.456. When the Mach number for the unsteady model tuning approaches to the measured fluttering Mach number, 0.502, at the flight altitude of 9,837 ft, the estimated flutter speed is approached to the measured flutter speed at this altitude. The minimum flutter speed difference between the estimated and measured flutter speed is -.14 %.

Unsteady Aerodynamic Model Tuning for Precise Flutter Prediction

NASA Technical Reports Server (NTRS)

Pak, Chan-gi

2011-01-01

A simple method for an unsteady aerodynamic model tuning is proposed in this study. This method is based on the direct modification of the aerodynamic influence coefficient matrices. The aerostructures test wing 2 flight-test data is used to demonstrate the proposed model tuning method. The flutter speed margin computed using only the test validated structural dynamic model can be improved using the additional unsteady aerodynamic model tuning, and then the flutter speed margin requirement of 15 percent in military specifications can apply towards the test validated aeroelastic model. In this study, unsteady aerodynamic model tunings are performed at two time invariant flight conditions, at Mach numbers of 0.390 and 0.456. When the Mach number for the unsteady aerodynamic model tuning approaches to the measured fluttering Mach number, 0.502, at the flight altitude of 9,837 ft, the estimated flutter speed is approached to the measured flutter speed at this altitude. The minimum flutter speed difference between the estimated and measured flutter speed is -0.14 percent.

Lay out, test verification and in orbit performance of HELIOS a temperature control system

NASA Technical Reports Server (NTRS)

Brungs, W.

1975-01-01

HELIOS temperature control system is described. The main design features and the impact of interactions between experiment, spacecraft system, and temperature control system requirements on the design are discussed. The major limitations of the thermal design regarding a closer sun approach are given and related to test experience and performance data obtained in orbit. Finally the validity of the test results achieved with prototype and flight spacecraft is evaluated by comparison between test data, orbit temperature predictions and flight data.

The extension of the thermal-vacuum test optimization program to multiple flights

NASA Technical Reports Server (NTRS)

Williams, R. E.; Byrd, J.

1981-01-01

The thermal vacuum test optimization model developed to provide an approach to the optimization of a test program based on prediction of flight performance with a single flight option in mind is extended to consider reflight as in space shuttle missions. The concept of 'utility', developed under the name of 'availability', is used to follow performance through the various options encountered when the capabilities of reflight and retrievability of space shuttle are available. Also, a 'lost value' model is modified to produce a measure of the probability of a mission's success, achieving a desired utility using a minimal cost test strategy. The resulting matrix of probabilities and their associated costs provides a means for project management to evaluate various test and reflight strategies.

Flight tests of the 4D flight guidance display

NASA Astrophysics Data System (ADS)

Below, Christian; von Viebahn, Harro; Purpus, Matthias

1997-06-01

A perspective primary flight and a navigation display format were evaluated in a flying testbed. The flight tests comprised ILS- and standard approaches as well as low level operations utilizing the depiction of a spatial channel, and demonstrations of the inherent ground proximity warning function. In the cockpit of the VFW614, the left seat was equipped with a sidestick and a flat panel display, which showed both the 4D-display an the Navigation Display format. Airline and airforce pilots flew several missions each. Although most of the pilots criticizes that a typical flight director commanding the aircraft's attitude was missing, they could follow the channel precisely. However, some airline pilots stated a lack of vertical guidance information during the final approach. Leaving and re- entering the channel could be easily accomplished form any direction. In summary pilots' assessment of the display concept yielded an overall improvement of SA. In particular it was stated that displays are an appropriate means to avoid CFIT accidents. With the fist prototypes of 3D- graphics generators designed for avionics available the flight evaluation will continue including feasibility demonstrations of high-performance graphics for civil and military aircraft applications.

Key Topics for High-Lift Research: A Joint Wind Tunnel/Flight Test Approach

NASA Technical Reports Server (NTRS)

Fisher, David; Thomas, Flint O.; Nelson, Robert C.

1996-01-01

Future high-lift systems must achieve improved aerodynamic performance with simpler designs that involve fewer elements and reduced maintenance costs. To expeditiously achieve this, reliable CFD design tools are required. The development of useful CFD-based design tools for high lift systems requires increased attention to unresolved flow physics issues. The complex flow field over any multi-element airfoil may be broken down into certain generic component flows which are termed high-lift building block flows. In this report a broad spectrum of key flow field physics issues relevant to the design of improved high lift systems are considered. It is demonstrated that in-flight experiments utilizing the NASA Dryden Flight Test Fixture (which is essentially an instrumented ventral fin) carried on an F-15B support aircraft can provide a novel and cost effective method by which both Reynolds and Mach number effects associated with specific high lift building block flows can be investigated. These in-flight high lift building block flow experiments are most effective when performed in conjunction with coordinated ground based wind tunnel experiments in low speed facilities. For illustrative purposes three specific examples of in-flight high lift building block flow experiments capable of yielding a high payoff are described. The report concludes with a description of a joint wind tunnel/flight test approach to high lift aerodynamics research.

A weighted optimization approach to time-of-flight sensor fusion.

PubMed

Schwarz, Sebastian; Sjostrom, Marten; Olsson, Roger

2014-01-01

Acquiring scenery depth is a fundamental task in computer vision, with many applications in manufacturing, surveillance, or robotics relying on accurate scenery information. Time-of-flight cameras can provide depth information in real-time and overcome short-comings of traditional stereo analysis. However, they provide limited spatial resolution and sophisticated upscaling algorithms are sought after. In this paper, we present a sensor fusion approach to time-of-flight super resolution, based on the combination of depth and texture sources. Unlike other texture guided approaches, we interpret the depth upscaling process as a weighted energy optimization problem. Three different weights are introduced, employing different available sensor data. The individual weights address object boundaries in depth, depth sensor noise, and temporal consistency. Applied in consecutive order, they form three weighting strategies for time-of-flight super resolution. Objective evaluations show advantages in depth accuracy and for depth image based rendering compared with state-of-the-art depth upscaling. Subjective view synthesis evaluation shows a significant increase in viewer preference by a factor of four in stereoscopic viewing conditions. To the best of our knowledge, this is the first extensive subjective test performed on time-of-flight depth upscaling. Objective and subjective results proof the suitability of our approach to time-of-flight super resolution approach for depth scenery capture.

Flight initiation by Ferruginous Hawks depends on disturbance type, experience, and the anthropogenic landscape

PubMed Central

Wellicome, Troy I.; Bayne, Erin M.

2017-01-01

The expansion of humans and their related infrastructure is increasing the likelihood that wildlife will interact with humans. When disturbed by humans, animals often change their behaviour, which can result in time and energetic costs to that animal. An animal's decision to change behaviour is likely related to the type of disturbance, the individual's past experience with disturbance, and the landscape in which the disturbance occurs. In southern Alberta and Saskatchewan, we quantified probability of flight initiation from the nest by Ferruginous Hawks (Buteo regalis) during approaches to nests by investigators. We tested if probability of flight was related to different disturbance types, previous experience, and the anthropogenic landscape in which individual Ferruginous Hawks nested. Probability of flight was related to the type of approach by the investigator, the number of previous visits by investigators, and the vehicular traffic around the nest. Approaches by humans on foot resulted in a greater probability of flight than those in a vehicle. Approaches in a vehicle via low traffic volume access roads were related to increased probability of flight relative to other road types. The number of previous investigator approaches to the nest increased the probability of flight. Overall, we found support that Ferruginous Hawks show habituation to vehicles and the positive reinforcement hypotheses as probability of flight was negatively related to an index of traffic activity near the nest. Our work emphasizes that complex, dynamic processes drive the decision to initiate flight from the nest, and contributes to the growing body of work explaining how responses to humans vary within species. PMID:28542334

Flight initiation by Ferruginous Hawks depends on disturbance type, experience, and the anthropogenic landscape.

PubMed

Nordell, Cameron J; Wellicome, Troy I; Bayne, Erin M

2017-01-01

The expansion of humans and their related infrastructure is increasing the likelihood that wildlife will interact with humans. When disturbed by humans, animals often change their behaviour, which can result in time and energetic costs to that animal. An animal's decision to change behaviour is likely related to the type of disturbance, the individual's past experience with disturbance, and the landscape in which the disturbance occurs. In southern Alberta and Saskatchewan, we quantified probability of flight initiation from the nest by Ferruginous Hawks (Buteo regalis) during approaches to nests by investigators. We tested if probability of flight was related to different disturbance types, previous experience, and the anthropogenic landscape in which individual Ferruginous Hawks nested. Probability of flight was related to the type of approach by the investigator, the number of previous visits by investigators, and the vehicular traffic around the nest. Approaches by humans on foot resulted in a greater probability of flight than those in a vehicle. Approaches in a vehicle via low traffic volume access roads were related to increased probability of flight relative to other road types. The number of previous investigator approaches to the nest increased the probability of flight. Overall, we found support that Ferruginous Hawks show habituation to vehicles and the positive reinforcement hypotheses as probability of flight was negatively related to an index of traffic activity near the nest. Our work emphasizes that complex, dynamic processes drive the decision to initiate flight from the nest, and contributes to the growing body of work explaining how responses to humans vary within species.

Ground-based and in-flight simulator studies of flight characteristics of a twin-fuselage passenger transport airplane during approach and landing

NASA Technical Reports Server (NTRS)

Grantham, W. D.; Smith, P. M.; Neely, W. R., Jr.; Deal, P. L.; Yenni, K. R.

1985-01-01

Six-degree-of-freedom ground-based and in-flight simulator studies were conducted to evaluate the low-speed flight characteristics of a twin-fuselage passenger transport airplane and to compare these characteristics with those of a large, single-fuselage (reference) transport configuration similar to the Lockheed C-5A airplane. The primary piloting task was the approach and landing task. The results of this study indicated that the twin-fuselage transport concept had acceptable but unsatisfactory longitudinal and lateral-directional low-speed flight characteristics, and that stability and control augmentation would be required in order to improve the handling qualities. Through the use of rate-command/attitude-hold augmentation in the pitch and roll axes, and the use of several turn coordination features, the handling qualities of the simulated transport were improved appreciably. The in-flight test results showed excellent agreement with those of the six-degree-of-freedom ground-based simulator handling qualities tests. As a result of the in-flight simulation study, a roll-control-induced normal-acceleration criterion was developed. The handling qualities of the augmented twin-fuselage passenger transport airplane exhibited an improvement over the handling characteristics of the reference (single-fuselage) transport.

Orion Flight Test 1 Architecture: Observed Benefits of a Model Based Engineering Approach

NASA Technical Reports Server (NTRS)

Simpson, Kimberly A.; Sindiy, Oleg V.; McVittie, Thomas I.

2012-01-01

This paper details how a NASA-led team is using a model-based systems engineering approach to capture, analyze and communicate the end-to-end information system architecture supporting the first unmanned orbital flight of the Orion Multi-Purpose Crew Exploration Vehicle. Along with a brief overview of the approach and its products, the paper focuses on the observed program-level benefits, challenges, and lessons learned; all of which may be applied to improve system engineering tasks for characteristically similarly challenges

A systems approach to solder joint fatigue in spacecraft electronic packaging

NASA Technical Reports Server (NTRS)

Ross, R. G., Jr.

1991-01-01

Differential expansion induced fatigue resulting from temperature cycling is a leading cause of solder joint failures in spacecraft. Achieving high reliability flight hardware requires that each element of the fatigue issue be addressed carefully. This includes defining the complete thermal-cycle environment to be experienced by the hardware, developing electronic packaging concepts that are consistent with the defined environments, and validating the completed designs with a thorough qualification and acceptance test program. This paper describes a useful systems approach to solder fatigue based principally on the fundamental log-strain versus log-cycles-to-failure behavior of fatigue. This fundamental behavior has been useful to integrate diverse ground test and flight operational thermal-cycle environments into a unified electronics design approach. Each element of the approach reflects both the mechanism physics that control solder fatigue, as well as the practical realities of the hardware build, test, delivery, and application cycle.

Flight Test Results on the Stability and Control of the F-15 Quiet Spike(TradeMark) Aircraft

NASA Technical Reports Server (NTRS)

Moua, Cheng M.; McWherter, Shaun C.; Cox, Timothy H.; Gera, Joe

2012-01-01

The Quiet Spike F-15B flight research program investigated supersonic shock reduction using a 24-ft sub-scale telescoping nose boom on an F-15B airplane. The program primary flight test objective was to collect flight data for aerodynamic and structural models validation up to 1.8 Mach. Other objectives were to validate the mechanical feasibility of a morphing fuselage at the operational conditions and determine the near-field shock wave characterization. The stability and controls objectives were to assess the effect of the spike on the stability, controllability, and handling qualities of the aircraft and to ensure adequate stability margins across the entire research flight envelop. The two main stability and controls issues were the effects of the telescoping nose boom influenced aerodynamics on the F-15B aircraft flight dynamics and air data and angle of attack sensors. This paper reports on the stability and controls flight envelope clearance methods and flight test analysis of the F-15B Quiet Spike. Brief pilot commentary on typical piloting tasks, approach and landing, refueling task, and air data sensitivity to the flight control system are also discussed in this report.

Annual Report to the NASA Administrator by the Aerospace Safety Advisory Panel on the Space Shuttle Program. Part 2: Summary of Information Developed in the Panel's Fact-Finding Activities

NASA Technical Reports Server (NTRS)

1977-01-01

The panel focused its attention on those areas that are considered most significant for flight success and safety. Elements required for the Approach and Landing Test Program, the Orbital Flight Test Program, and those management systems and their implementation which directly affect safety, reliability, and quality control, were investigated. Ground facilities and the training programs for the ground and flight crews were studied. Of special interest was the orbiter thermal protection subsystems.

Flight test experience and controlled impact of a remotely piloted jet transport aircraft

NASA Technical Reports Server (NTRS)

Horton, Timothy W.; Kempel, Robert W.

1988-01-01

The Dryden Flight Research Center Facility of NASA Ames Research Center (Ames-Dryden) and the FAA conducted the controlled impact demonstration (CID) program using a large, four-engine, remotely piloted jet transport airplane. Closed-loop primary flight was controlled through the existing onboard PB-20D autopilot which had been modified for the CID program. Uplink commands were sent from a ground-based cockpit and digital computer in conjunction with an up-down telemetry link. These uplink commands were received aboard the airplane and transferred through uplink interface systems to the modified PB-20D autopilot. Both proportional and discrete commands were produced by the ground system. Prior to flight tests, extensive simulation was conducted during the development of ground-based digital control laws. The control laws included primary control, secondary control, and racetrack and final approach guidance. Extensive ground checks were performed on all remotely piloted systems; however, piloted flight tests were the primary method and validation of control law concepts developed from simulation. The design, development, and flight testing of control laws and systems required to accomplish the remotely piloted mission are discussed.

Reduced-gravity environment hardware demonstrations of a prototype miniaturized flow cytometer and companion microfluidic mixing technology.

PubMed

Phipps, William S; Yin, Zhizhong; Bae, Candice; Sharpe, Julia Z; Bishara, Andrew M; Nelson, Emily S; Weaver, Aaron S; Brown, Daniel; McKay, Terri L; Griffin, DeVon; Chan, Eugene Y

2014-11-13

Until recently, astronaut blood samples were collected in-flight, transported to earth on the Space Shuttle, and analyzed in terrestrial laboratories. If humans are to travel beyond low Earth orbit, a transition towards space-ready, point-of-care (POC) testing is required. Such testing needs to be comprehensive, easy to perform in a reduced-gravity environment, and unaffected by the stresses of launch and spaceflight. Countless POC devices have been developed to mimic laboratory scale counterparts, but most have narrow applications and few have demonstrable use in an in-flight, reduced-gravity environment. In fact, demonstrations of biomedical diagnostics in reduced gravity are limited altogether, making component choice and certain logistical challenges difficult to approach when seeking to test new technology. To help fill the void, we are presenting a modular method for the construction and operation of a prototype blood diagnostic device and its associated parabolic flight test rig that meet the standards for flight-testing onboard a parabolic flight, reduced-gravity aircraft. The method first focuses on rig assembly for in-flight, reduced-gravity testing of a flow cytometer and a companion microfluidic mixing chip. Components are adaptable to other designs and some custom components, such as a microvolume sample loader and the micromixer may be of particular interest. The method then shifts focus to flight preparation, by offering guidelines and suggestions to prepare for a successful flight test with regard to user training, development of a standard operating procedure (SOP), and other issues. Finally, in-flight experimental procedures specific to our demonstrations are described.

Visual Advantage of Enhanced Flight Vision System During NextGen Flight Test Evaluation

NASA Technical Reports Server (NTRS)

Kramer, Lynda J.; Harrison, Stephanie J.; Bailey, Randall E.; Shelton, Kevin J.; Ellis, Kyle K.

2014-01-01

Synthetic Vision Systems and Enhanced Flight Vision System (SVS/EFVS) technologies have the potential to provide additional margins of safety for aircrew performance and enable operational improvements for low visibility operations in the terminal area environment. Simulation and flight tests were jointly sponsored by NASA's Aviation Safety Program, Vehicle Systems Safety Technology project and the Federal Aviation Administration (FAA) to evaluate potential safety and operational benefits of SVS/EFVS technologies in low visibility Next Generation Air Transportation System (NextGen) operations. The flight tests were conducted by a team of Honeywell, Gulfstream Aerospace Corporation and NASA personnel with the goal of obtaining pilot-in-the-loop test data for flight validation, verification, and demonstration of selected SVS/EFVS operational and system-level performance capabilities. Nine test flights were flown in Gulfstream's G450 flight test aircraft outfitted with the SVS/EFVS technologies under low visibility instrument meteorological conditions. Evaluation pilots flew 108 approaches in low visibility weather conditions (600 feet to 3600 feet reported visibility) under different obscurants (mist, fog, drizzle fog, frozen fog) and sky cover (broken, overcast). Flight test videos were evaluated at three different altitudes (decision altitude, 100 feet radar altitude, and touchdown) to determine the visual advantage afforded to the pilot using the EFVS/Forward-Looking InfraRed (FLIR) imagery compared to natural vision. Results indicate the EFVS provided a visual advantage of two to three times over that of the out-the-window (OTW) view. The EFVS allowed pilots to view the runway environment, specifically runway lights, before they would be able to OTW with natural vision.

Reduced-gravity Environment Hardware Demonstrations of a Prototype Miniaturized Flow Cytometer and Companion Microfluidic Mixing Technology

PubMed Central

Bae, Candice; Sharpe, Julia Z.; Bishara, Andrew M.; Nelson, Emily S.; Weaver, Aaron S.; Brown, Daniel; McKay, Terri L.; Griffin, DeVon; Chan, Eugene Y.

2014-01-01

Until recently, astronaut blood samples were collected in-flight, transported to earth on the Space Shuttle, and analyzed in terrestrial laboratories. If humans are to travel beyond low Earth orbit, a transition towards space-ready, point-of-care (POC) testing is required. Such testing needs to be comprehensive, easy to perform in a reduced-gravity environment, and unaffected by the stresses of launch and spaceflight. Countless POC devices have been developed to mimic laboratory scale counterparts, but most have narrow applications and few have demonstrable use in an in-flight, reduced-gravity environment. In fact, demonstrations of biomedical diagnostics in reduced gravity are limited altogether, making component choice and certain logistical challenges difficult to approach when seeking to test new technology. To help fill the void, we are presenting a modular method for the construction and operation of a prototype blood diagnostic device and its associated parabolic flight test rig that meet the standards for flight-testing onboard a parabolic flight, reduced-gravity aircraft. The method first focuses on rig assembly for in-flight, reduced-gravity testing of a flow cytometer and a companion microfluidic mixing chip. Components are adaptable to other designs and some custom components, such as a microvolume sample loader and the micromixer may be of particular interest. The method then shifts focus to flight preparation, by offering guidelines and suggestions to prepare for a successful flight test with regard to user training, development of a standard operating procedure (SOP), and other issues. Finally, in-flight experimental procedures specific to our demonstrations are described. PMID:25490614

Flight testing and frequency domain analysis for rotorcraft handling qualities characteristics

NASA Technical Reports Server (NTRS)

Ham, Johnnie A.; Gardner, Charles K.; Tischler, Mark B.

1993-01-01

A demonstration of frequency domain flight testing techniques and analyses was performed on a U.S. Army OH-58D helicopter in support of the OH-58D Airworthiness and Flight Characteristics Evaluation and the Army's development and ongoing review of Aeronautical Design Standard 33C, Handling Qualities Requirements for Military Rotorcraft. Hover and forward flight (60 knots) tests were conducted in 1 flight hour by Army experimental test pilots. Further processing of the hover data generated a complete database of velocity, angular rate, and acceleration frequency responses to control inputs. A joint effort was then undertaken by the Airworthiness Qualification Test Directorate (AQTD) and the U.S. Army Aeroflightdynamics Directorate (AFDD) to derive handling qualities information from the frequency response database. A significant amount of information could be extracted from the frequency domain database using a variety of approaches. This report documents numerous results that have been obtained from the simple frequency domain tests; in many areas, these results provide more insight into the aircraft dynamics that affect handling qualities than to traditional flight tests. The handling qualities results include ADS-33C bandwidth and phase delay calculations, vibration spectral determinations, transfer function models to examine single axis results, and a six degree of freedom fully coupled state space model. The ability of this model to accurately predict aircraft responses was verified using data from pulse inputs. This report also documents the frequency-sweep flight test technique and data analysis used to support the tests.

High-Rate Wireless Airborne Network Demonstration (HiWAND) Flight Test Results

NASA Technical Reports Server (NTRS)

Franz, Russell

2008-01-01

An increasing number of flight research and airborne science experiments now contain network-ready systems that could benefit from a high-rate bidirectional air-to-ground network link. A prototype system, the High-Rate Wireless Airborne Network Demonstration, was developed from commercial off-the-shelf components while leveraging the existing telemetry infrastructure on the Western Aeronautical Test Range. This approach resulted in a cost-effective, long-range, line-of-sight network link over the S and the L frequency bands using both frequency modulation and shaped-offset quadrature phase-shift keying modulation. This report discusses system configuration and the flight test results.

Planned flight test of a mercury ion auxiliary propulsion system. Part 2: Integration with host spacecraft

NASA Technical Reports Server (NTRS)

Knight, R. M.

1978-01-01

The objectives of the flight test and a description on how those objectives are in support of an overall program goal of attaining user application were described. The approach to accomplishment was presented as it applies to integrating the propulsion system with the host spacecraft. A number of known interface design considerations which affect the propulsion system and the spacecraft were discussed. Analogies were drawn comparing the relationship of the organizations involved with this flight test with those anticipated for future operational missions. The paper also expanded upon objectives, system description, mission operations, and measurement of plume effects.

High-Rate Wireless Airborne Network Demonstration (HiWAND) Flight Test Results

NASA Technical Reports Server (NTRS)

Franz, Russell

2007-01-01

An increasing number of flight research and airborne science experiments now contain network-ready systems that could benefit from a high-rate bidirectional air-to-ground network link. A prototype system, the High-Rate Wireless Airborne Network Demonstration, was developed from commercial off-the-shelf components while leveraging the existing telemetry infrastructure on the Western Aeronautical Test Range. This approach resulted in a cost-effective, long-range, line-of-sight network link over the S and the L frequency bands using both frequency modulation and shaped-offset quadrature phase-shift keying modulation. This paper discusses system configuration and the flight test results.

Magnetic Testing, and Modeling, Simulation and Analysis for Space Applications

NASA Technical Reports Server (NTRS)

Boghosian, Mary; Narvaez, Pablo; Herman, Ray

2012-01-01

The Aerospace Corporation (Aerospace) and Lockheed Martin Space Systems (LMSS) participated with Jet Propulsion Laboratory (JPL) in the implementation of a magnetic cleanliness program of the NASA/JPL JUNO mission. The magnetic cleanliness program was applied from early flight system development up through system level environmental testing. The JUNO magnetic cleanliness program required setting-up a specialized magnetic test facility at Lockheed Martin Space Systems for testing the flight system and a testing program with facility for testing system parts and subsystems at JPL. The magnetic modeling, simulation and analysis capability was set up and performed by Aerospace to provide qualitative and quantitative magnetic assessments of the magnetic parts, components, and subsystems prior to or in lieu of magnetic tests. Because of the sensitive nature of the fields and particles scientific measurements being conducted by the JUNO space mission to Jupiter, the imposition of stringent magnetic control specifications required a magnetic control program to ensure that the spacecraft's science magnetometers and plasma wave search coil were not magnetically contaminated by flight system magnetic interferences. With Aerospace's magnetic modeling, simulation and analysis and JPL's system modeling and testing approach, and LMSS's test support, the project achieved a cost effective approach to achieving a magnetically clean spacecraft. This paper presents lessons learned from the JUNO magnetic testing approach and Aerospace's modeling, simulation and analysis activities used to solve problems such as remnant magnetization, performance of hard and soft magnetic materials within the targeted space system in applied external magnetic fields.

Benefits of Spacecraft Level Vibration Testing

NASA Technical Reports Server (NTRS)

Gordon, Scott; Kern, Dennis L.

2015-01-01

NASA-HDBK-7008 Spacecraft Level Dynamic Environments Testing discusses the approaches, benefits, dangers, and recommended practices for spacecraft level dynamic environments testing, including vibration testing. This paper discusses in additional detail the benefits and actual experiences of vibration testing spacecraft for NASA Goddard Space Flight Center (GSFC) and Jet Propulsion Laboratory (JPL) flight projects. JPL and GSFC have both similarities and differences in their spacecraft level vibration test approach: JPL uses a random vibration input and a frequency range usually starting at 5 Hz and extending to as high as 250 Hz. GSFC uses a sine sweep vibration input and a frequency range usually starting at 5 Hz and extending only to the limits of the coupled loads analysis (typically 50 to 60 Hz). However, both JPL and GSFC use force limiting to realistically notch spacecraft resonances and response (acceleration) limiting as necessary to protect spacecraft structure and hardware from exceeding design strength capabilities. Despite GSFC and JPL differences in spacecraft level vibration test approaches, both have uncovered a significant number of spacecraft design and workmanship anomalies in vibration tests. This paper will give an overview of JPL and GSFC spacecraft vibration testing approaches and provide a detailed description of spacecraft anomalies revealed.

Ares-I-X Stability and Control Flight Test: Analysis and Plans

NASA Technical Reports Server (NTRS)

Brandon, Jay M.; Derry, Stephen D.; Heim, Eugene H.; Hueschen, Richard M.; Bacon, Barton J.

2008-01-01

The flight test of the Ares I-X vehicle provides a unique opportunity to reduce risk of the design of the Ares I vehicle and test out design, math modeling, and analysis methods. One of the key features of the Ares I design is the significant static aerodynamic instability coupled with the relatively flexible vehicle - potentially resulting in a challenging controls problem to provide adequate flight path performance while also providing adequate structural mode damping and preventing adverse control coupling to the flexible structural modes. Another challenge is to obtain enough data from the single flight to be able to conduct analysis showing the effectiveness of the controls solutions and have data to inform design decisions for Ares I. This paper will outline the modeling approaches and control system design to conduct this flight test, and also the system identification techniques developed to extract key information such as control system performance (gain/phase margins, for example), structural dynamics responses, and aerodynamic model estimations.

Flight test experience and controlled impact of a large, four-engine, remotely piloted airplane

NASA Technical Reports Server (NTRS)

Kempel, R. W.; Horton, T. W.

1985-01-01

A controlled impact demonstration (CID) program using a large, four engine, remotely piloted transport airplane was conducted. Closed loop primary flight control was performed from a ground based cockpit and digital computer in conjunction with an up/down telemetry link. Uplink commands were received aboard the airplane and transferred through uplink interface systems to a highly modified Bendix PB-20D autopilot. Both proportional and discrete commands were generated by the ground pilot. Prior to flight tests, extensive simulation was conducted during the development of ground based digital control laws. The control laws included primary control, secondary control, and racetrack and final approach guidance. Extensive ground checks were performed on all remotely piloted systems. However, manned flight tests were the primary method of verification and validation of control law concepts developed from simulation. The design, development, and flight testing of control laws and the systems required to accomplish the remotely piloted mission are discussed.

Ares I-X Flight Test Validation of Control Design Tools in the Frequency-Domain

NASA Technical Reports Server (NTRS)

Johnson, Matthew; Hannan, Mike; Brandon, Jay; Derry, Stephen

2011-01-01

A major motivation of the Ares I-X flight test program was to Design for Data, in order to maximize the usefulness of the data recorded in support of Ares I modeling and validation of design and analysis tools. The Design for Data effort was intended to enable good post-flight characterizations of the flight control system, the vehicle structural dynamics, and also the aerodynamic characteristics of the vehicle. To extract the necessary data from the system during flight, a set of small predetermined Programmed Test Inputs (PTIs) was injected directly into the TVC signal. These PTIs were designed to excite the necessary vehicle dynamics while exhibiting a minimal impact on loads. The method is similar to common approaches in aircraft flight test programs, but with unique launch vehicle challenges due to rapidly changing states, short duration of flight, a tight flight envelope, and an inability to repeat any test. This paper documents the validation effort of the stability analysis tools to the flight data which was performed by comparing the post-flight calculated frequency response of the vehicle to the frequency response calculated by the stability analysis tools used to design and analyze the preflight models during the control design effort. The comparison between flight day frequency response and stability tool analysis for flight of the simulated vehicle shows good agreement and provides a high level of confidence in the stability analysis tools for use in any future program. This is true for both a nominal model as well as for dispersed analysis, which shows that the flight day frequency response is enveloped by the vehicle s preflight uncertainty models.

Virtual decoupling flight control via real-time trajectory synthesis and tracking

NASA Astrophysics Data System (ADS)

Zhang, Xuefu

The production of the General Aviation industry has declined in the past 25 years. Ironically, however, the increasing demand for air travel as a fast, safe, and high-quality mode of transportation has been far from satisfied. Addressing this demand shortfall with personal air transportation necessitates advanced systems for navigation, guidance, control, flight management, and flight traffic control. Among them, an effective decoupling flight control system will not only improve flight quality, safety, and simplicity, and increase air space usage, but also reduce expenses on pilot initial and current training, and thus expand the current market and explore new markets. Because of the formidable difficulties encountered in the actual decoupling of non-linear, time-variant, and highly coupled flight control systems through traditional approaches, a new approach, which essentially converts the decoupling problem into a real-time trajectory synthesis and tracking problem, is employed. Then, the converted problem is solved and a virtual decoupling effect is achieved. In this approach, a trajectory in inertial space can be predefined and dynamically modified based on the flight mission and the pilot's commands. A feedforward-feedback control architecture is constructed to guide the airplane along the trajectory as precisely as possible. Through this approach, the pilot has much simpler, virtually decoupled control of the airplane in terms of speed, flight path angle and horizontal radius of curvature. To verify and evaluate this approach, extensive computer simulation is performed. A great deal of test cases are designed for the flight control under different flight conditions. The simulation results show that our decoupling strategy is satisfactory and promising, and therefore the research can serve as a consolidated foundation for future practical applications.

Evaluation of Aerosol Optical Thickness algorithm for Geostationary Environmental Monitoring Spectrometer (GEMS) Using the OMI Instrument over East Asia

NASA Astrophysics Data System (ADS)

Go, S.; Kim, J.; KIM, M.; Choi, M.; Lim, H.; Torres, O.; Chang, L.; Hong, J.

2016-12-01

Nitrous oxide (N2O) is a powerful greenhouse gas and ozone depleting substance. With high atmospheric backgrounds and small relative signals, N2O emissions have been challenging to observe and understand on regional scales with traditional instrumentation. Fast-response airborne measurements with high precision and accuracy can potentially bridge this observational gap. Here we present flight assessments of a new flight system based on an Aerodyne mini-spectrometer as well as a Los Gatos N2O/CO analyzer during the Fertilizer Emissions Airborne Study (FEAST). With the Scientific Aviation Mooney aircraft, we conducted test flights for both analyzers where a known calibration gas was sampled throughout the flight (`null' tests). Clear altitude/cabin-pressure dependencies were observed for both analyzers if operated in an "off-the-shelf' manner. For the remainder of test flights and the FEAST campaign we used a new flight system based on an Aerodyne mini-spectrometer with the addition of a custom pressure control/calibration system. Instead of using traditional approaches with spectral-zeros and infrequent in-flight calibrations, we employ a high-flow system with stable flow control to enable high frequency (2 minutes), short duration (15 seconds) sampling of a known calibration gas. This approach, supported by the null test, enables correction for spectral drift caused by a variety of factors while maintaining a 90% duty cycle for 1Hz sampling from an aircraft. Preliminary in-flight precisions are estimated at 0.05 ppb, 0.1 ppm, 1 ppb, and 10 ppm for N2O, CO2, CO, and H2O respectively. We also present a further 40 hours of inter-comparison in flight with a Picarro 2301-f ring-down spectrometer demonstrating consistency between CO2 and H2O measurements and no altitude dependent error.

Stability and Controls Analysis and Flight Test Results of a 24-Foot Telescoping Nose Boom on an F-15B Airplane

NASA Technical Reports Server (NTRS)

Moua, Cheng M.; Cox, Timothy H.; McWherter, Shaun C.

2008-01-01

The Quiet Spike(TradeMark) F-15B flight research program investigated supersonic shock reduction using a 24-ft telescoping nose boom on an F-15B airplane. The program goal was to collect flight data for model validation up to 1.8 Mach. In the area of stability and controls, the primary concerns were to assess the potential destabilizing effect of the oversized nose boom on the stability, controllability, and handling qualities of the airplane and to ensure adequate stability margins across the entire research flight envelope. This paper reports on the stability and control analytical methods, flight envelope clearance approach, and flight test results of the F-15B telescoping nose boom configuration. Also discussed are brief pilot commentary on typical piloting tasks and refueling tasks.

The flying classroom - a cost effective integrated approach to learning and teaching flight dynamics

NASA Astrophysics Data System (ADS)

Bromfield, Michael A.; Belberov, Aleksandar

2017-11-01

In the UK, the Royal Aeronautical Society recommends the inclusion of practical flight exercises for accredited undergraduate aerospace engineering programmes to enhance learning and student experience. The majority of academic institutions teaching aerospace in the UK separate the theory and practice of flight dynamics with students attending a series of lectures supplemented by an intensive one-day flight exercise. Performance and/or handling qualities flight tests are performed in a dedicated aircraft fitted with specialist equipment for the recording and presentation of flight data. This paper describes an innovative approach to better integrate theory and practice and the use of portable Commercial-off-The-Shelf (COTS) technologies to enable a range of standard, unmodified aircraft to be used. The integration of theory and practice has enriched learning and teaching, improved coursework grades and the student experience. The use of COTS and unmodified aircraft has reduced costs and enabled increased student participation.

X-31 quasi-tailless flight demonstration

NASA Technical Reports Server (NTRS)

Huber, Peter; Schellenger, Harvey G.

1994-01-01

The primary objective of the quasi-tailless flight demonstration is to demonstrate the feasibility of using thrust vectoring for directional control of an unstable aircraft. By using this low-cost, low-risk approach it is possible to get information about required thrust vector control power and deflection rates from an inflight experiment as well as insight in low-power thrust vectoring issues. The quasi-tailless flight demonstration series with the X-31 began in March 1994. The demonstration flight condition was Mach 1.2 at 37,500 feet. A series of basic flying quality maneuvers, doublets, bank to bank rolls, and wind-up-turns have been performed with a simulated 100% vertical tail reduction. Flight test and supporting simulation demonstrated that the quasi-tailless approach is effective in representing the reduced stability of tailless configurations. The flights also demonstrated that thrust vectoring could be effectively used to stabilize a directionally unstable configuration and provide control power for maneuver coordination.

STS Approach and Landing Test (ALT): Flight 5 - Slow Motion video of pilot-induced oscillation (PIO)

NASA Technical Reports Server (NTRS)

1977-01-01

During 1977 the NASA Dryden Flight Research Center, Edwards, California, hosted the Approach and Landing Tests for the space shuttle prototype Enterprise. Since the shuttles would land initially on Rogers Dry Lakebed adjacent to Dryden on Edwards Air Force Base, NASA had already modified a Boeing 747 to carry them back to their launch site at Kennedy Space Center, Florida. Computer calculations and simulations had predicted the mated shuttle and 747 could fly together safely, but NASA wanted to verify that prediction in a controlled flight-test environment before the shuttles went into operation. The agency also wanted to glide test the orbiter to ensure it could land safely before sending it into space with human beings aboard. So NASA's Johnson Space Center, Houston, Texas, developed a three-phase test program. First, an unpiloted-captive phase tested the shuttle/747 combination without a crew on the Enterprise in case of a problem that required jettisoning the prototype. There were three taxi tests and five flight tests without a crew in the shuttle. That phase ended on March 2, 1977. The second or captive-active phase-completed on July 26, 1977, flew the orbiter mated to the 747 with a two-person crew inside. Finally there were five flights-completed on October 26, 1977, in which the orbiter separated from the Shuttle Carrier Aircraft (SCA, as the 747 was designated) and landed. Beginning on August 12, 1977, the first four landings took place uneventfully on lakebed runways, but the fifth occurred on the concrete, 15,000-foot runway at Edwards. For the first three flights, a tail cone was placed around the dummy main engines to reduce buffeting. The tail-cone fairing was removed for the last two flights. This movie clip begins with the Enterprise just prior to touchdown on the main runway at Edwards AFB after it's fifth and final unpowered free flight. Shuttle pilots Gordon Fullerton and Fred Haise were attempting a couple of firsts on this flight--a precision 'spot' landing on the concrete runway and flying the orbiter without it's tail-cone fairing, since the previous lakebed landing without the fairing had been made by Joe Engle and Richard Truly. Both Haise and Fullerton had prepared as well as possible for the variables of this mission by flying simulated approach profiles in NASA's shuttle training aircraft. However, as with most simulations, the performance wasn't completely identical to that of the real vehicle. Consequently Haise, the mission commander in the left seat, was too fast on the orbiter's landing approach. Deploying the speed brakes, he tried vainly to hit the assigned landing mark but in the stress of the moment, began to overcorrect the vehicle. The orbiter entered a pilot-induced oscillation or PIO along both it's roll and pitch axis causing the vehicle to begin to 'porpoise' down the runway. As it settled down to land it began to bounce from one main landing gear to the next before being brought under control and finally landed by the crew. Engineers at Dryden later determined that a roughly 270-millisecond time delay in the space shuttle's fly-by-wire system had been the cause of the problem, which was then explored with NASA Dryden's F-8 Digital Fly-By-Wire aircraft and corrected with a suppression filter integrated into the orbiter's flight control system.

STS Approach and Landing Test (ALT): Flight 5 - pilot-induced oscillation (PIO) on landing

NASA Technical Reports Server (NTRS)

1977-01-01

During 1977 the NASA Dryden Flight Research Center, Edwards, California, hosted the Approach and Landing Tests for the space shuttle prototype Enterprise. Since the shuttles would land initially on Rogers Dry Lakebed adjacent to Dryden on Edwards Air Force Base, NASA had already modified a Boeing 747 to carry them back to their launch site at Kennedy Space Center, Florida. Computer calculations and simulations had predicted the mated shuttle and 747 could fly together safely, but NASA wanted to verify that prediction in a controlled flight-test environment before the shuttles went into operation. The agency also wanted to glide test the orbiter to ensure it could land safely before sending it into space with human beings aboard. So NASA's Johnson Space Center, Houston, Texas, developed a three-phase test program. First, an unpiloted-captive phase tested the shuttle/747 combination without a crew on the Enterprise in case of a problem that required jettisoning the prototype. There were three taxi tests and five flight tests without a crew in the shuttle. That phase ended on March 2, 1977. The second or captive-active phase-completed on July 26, 1977, flew the orbiter mated to the 747 with a two-person crew inside. Finally there were five flights-completed on October 26, 1977, in which the orbiter separated from the Shuttle Carrier Aircraft (SCA, as the 747 was designated) and landed. Beginning on August 12, 1977, the first four landings took place uneventfully on lakebed runways, but the fifth occurred on the concrete, 15,000-foot runway at Edwards. For the first three flights, a tail cone was placed around the dummy main engines to reduce buffeting. The tail-cone fairing was removed for the last two flights. This movie clip begins with the Enterprise just prior to touchdown on the main runway at Edwards AFB after it's fifth and final unpowered free flight. Shuttle pilots Gordon Fullerton and Fred Haise were attempting a couple of firsts on this flight--a precision 'spot' landing on the concrete runway and flying the orbiter without it's tail-cone fairing, since the previous lakebed landing without the fairing had been made by Joe Engle and Richard Truly. Both Haise and Fullerton had prepared as well as possible for the variables of this mission by flying simulated approach profiles in NASA's shuttle training aircraft. However, as with most simulations, the performance wasn't completely identical to that of the real vehicle. Consequently Haise, the mission commander in the left seat, was too fast on the orbiter's landing approach. Deploying the speed brakes, he tried vainly to hit the assigned landing mark but in the stress of the moment, began to overcorrect the vehicle. The orbiter entered a pilot-induced oscillation or PIO along both it's roll and pitch axis causing the vehicle to begin to 'porpoise' down the runway. As it settled down to land it began to bounce from one main landing gear to the next before being brought under control and finally landed by the crew. Engineers at Dryden later determined that a roughly 270-millisecond time delay in the space shuttle's fly-by-wire system had been the cause of the problem, which was then explored with NASA Dryden's F-8 Digital Fly-By-Wire aircraft and corrected with a suppression filter integrated into the orbiter's flight control system.

Quiet Spike(TradeMark) Build-up Ground Vibration Testing Approach

NASA Technical Reports Server (NTRS)

Spivey, Natalie D.; Herrera, Claudia Y.; Truax, Roger; Pak, Chan-gi; Freund, Donald

2007-01-01

Flight tests of Gulfstream Aerospace Corporation s Quiet Spike(TradeMark) hardware were recently completed on the NASA Dryden Flight Research Center F-15B airplane. NASA Dryden uses a modified F-15B airplane as a testbed aircraft to cost-effectively fly flight research experiments that are typically mounted underneath the F-15B airplane, along the fuselage centerline. For the Quiet Spike(TradeMark) experiment, however, instead of a centerline mounting, a relatively long forward-pointing boom was attached to the radar bulkhead of the F-15B airplane. The Quiet Spike(TradeMark) experiment is a stepping-stone to airframe structural morphing technologies designed to mitigate the sonic-boom strength of business jets over land. The Quiet Spike(TradeMark) boom is a concept in which an aircraft s noseboom would be extended prior to supersonic acceleration. This morphing effectively lengthens the aircraft, thus reducing the peak sonic-boom amplitude, but is also expected to partition the otherwise strong bow shock into a series of reduced-strength, noncoalescing shocklets. Prior to flying the Quiet Spike(TradeMark) experiment on the F-15B airplane several ground vibration tests were required to understand the Quiet Spike(TradeMark) modal characteristics and coupling effects with the F-15B airplane. However, due to the flight hardware availability and compressed schedule requirements, a "traditional" ground vibration test of the mated F-15B Quiet Spike(TradeMark) ready-for- flight configuration did not leave sufficient time available for the finite element model update and flutter analyses before flight testing. Therefore, a "nontraditional" ground vibration testing approach was taken. This paper provides an overview of each phase of the "nontraditional" ground vibration testing completed for the Quiet Spike(TradeMark) project which includes the test setup details, instrumentation layout, and modal results obtained in support of the structural dynamic modeling and flutter analyses.

Design and flight test of a differential GPS/inertial navigation system for approach/landing guidance

NASA Technical Reports Server (NTRS)

Vallot, Lawrence; Snyder, Scott; Schipper, Brian; Parker, Nigel; Spitzer, Cary

1991-01-01

NASA-Langley has conducted a flight test program evaluating a differential GPS/inertial navigation system's (DGPS/INS) utility as an approach/landing aid. The DGPS/INS airborne and ground components are based on off-the-shelf transport aircraft avionics, namely a global positioning/inertial reference unit (GPIRU) and two GPS sensor units (GPSSUs). Systematic GPS errors are measured by the ground GPSSU and transmitted to the aircraft GPIRU, allowing the errors to be eliminated or greatly reduced in the airborne equipment. Over 120 landings were flown; 36 of these were fully automatic DGPS/INS landings.

Implementation of an Adaptive Controller System from Concept to Flight Test

NASA Technical Reports Server (NTRS)

Larson, Richard R.; Burken, John J.; Butler, Bradley S.

2009-01-01

The National Aeronautics and Space Administration Dryden Flight Research Center (Edwards, California) is conducting ongoing flight research using adaptive controller algorithms. A highly modified McDonnell-Douglas NF-15B airplane called the F-15 Intelligent Flight Control System (IFCS) was used for these algorithms. This airplane has been modified by the addition of canards and by changing the flight control systems to interface a single-string research controller processor for neural network algorithms. Research goals included demonstration of revolutionary control approaches that can efficiently optimize aircraft performance for both normal and failure conditions, and to advance neural-network-based flight control technology for new aerospace systems designs. Before the NF-15B IFCS airplane was certified for flight test, however, certain processes needed to be completed. This paper presents an overview of these processes, including a description of the initial adaptive controller concepts followed by a discussion of modeling formulation and performance testing. Upon design finalization, the next steps are: integration with the system interfaces, verification of the software, validation of the hardware to the requirements, design of failure detection, development of safety limiters to minimize the effect of erroneous neural network commands, and creation of flight test control room displays to maximize human situational awareness.

Advanced Stirling Convertor Dynamic Test Approach and Results

NASA Technical Reports Server (NTRS)

Meer, David W.; Hill, Dennis; Ursic, Joseph J.

2010-01-01

The U.S. Department of Energy (DOE), Lockheed Martin Corporation (LM), and NASA Glenn Research Center (GRC) have been developing the Advanced Stirling Radioisotope Generator (ASRG) for use as a power system for space science missions. As part of the extended operation testing of this power system, the Advanced Stirling Convertors (ASC) at NASA GRC undergo a vibration test sequence intended to simulate the vibration history that an ASC would experience when used in an ASRG for a space mission. This sequence includes testing at workmanship and flight acceptance levels interspersed with periods of extended operation to simulate prefueling and post fueling. The final step in the test sequence utilizes additional testing at flight acceptance levels to simulate launch. To better replicate the acceleration profile seen by an ASC incorporated into an ASRG, the input spectra used in testing the convertors was modified based on dynamic testing of the ASRG Engineering Unit (ASRG EU) at LM. This paper outlines the overall test approach, summarizes the test results from the ASRG EU, describes the incorporation of those results into the test approach, and presents the results of applying the test approach to the ASC-1 #3 and #4 convertors. The test results include data from several accelerometers mounted on the convertors as well as the piston position and output power variables.

Evaluation of Candidate Millimeter Wave Sensors for Synthetic Vision

NASA Technical Reports Server (NTRS)

Alexander, Neal T.; Hudson, Brian H.; Echard, Jim D.

1994-01-01

The goal of the Synthetic Vision Technology Demonstration Program was to demonstrate and document the capabilities of current technologies to achieve safe aircraft landing, take off, and ground operation in very low visibility conditions. Two of the major thrusts of the program were (1) sensor evaluation in measured weather conditions on a tower overlooking an unused airfield and (2) flight testing of sensor and pilot performance via a prototype system. The presentation first briefly addresses the overall technology thrusts and goals of the program and provides a summary of MMW sensor tower-test and flight-test data collection efforts. Data analysis and calibration procedures for both the tower tests and flight tests are presented. The remainder of the presentation addresses the MMW sensor flight-test evaluation results, including the processing approach for determination of various performance metrics (e.g., contrast, sharpness, and variability). The variation of the very important contrast metric in adverse weather conditions is described. Design trade-off considerations for Synthetic Vision MMW sensors are presented.

Quality assurance plan for Solar Maximum Mission (SSM) Instruments electronic assembly - HRUV spectrometer/polarimeter

NASA Technical Reports Server (NTRS)

1976-01-01

The quality assurance program demonstrates recognition of the quality aspects and an organized approach to achieve them. It ensures that quality requirements are determined and satisfied throughout all phases of contract performance, including preliminary and engineering design, development, fabrication, processing, assembly, inspection, test, checkout, packaging, shipping, storage, maintenance field use, flight preparations, flight operations and post-flight analysis, as applicable.

Analytical study to define a helicopter stability derivative extraction method, volume 1

NASA Technical Reports Server (NTRS)

Molusis, J. A.

1973-01-01

A method is developed for extracting six degree-of-freedom stability and control derivatives from helicopter flight data. Different combinations of filtering and derivative estimate are investigated and used with a Bayesian approach for derivative identification. The combination of filtering and estimate found to yield the most accurate time response match to flight test data is determined and applied to CH-53A and CH-54B flight data. The method found to be most accurate consists of (1) filtering flight test data with a digital filter, followed by an extended Kalman filter (2) identifying a derivative estimate with a least square estimator, and (3) obtaining derivatives with the Bayesian derivative extraction method.

Flight evaluation of a pneumatic system for unsteady pressure measurements using conventional sensors

NASA Technical Reports Server (NTRS)

Curry, Robert E.; Gilyard, Glenn B.

1989-01-01

A flight experiment was conducted to evaluate a pressure measurement system which uses pneumatic tubing and remotely located electronically scanned pressure transducer modules for in-flight unsteady aerodynamic studies. A parametric study of tubing length and diameter on the attenuation and lag of the measured signals was conducted. The hardware was found to operate satisfactorily at rates of up to 500 samples/sec per port in flight. The signal attenuation and lag due to tubing were shown to increase with tubing length, decrease with tubing diameter, and increase with altitude over the ranges tested. Measurable signal levels were obtained for even the longest tubing length tested, 4 ft, at frequencies up to 100 Hz. This instrumentation system approach provides a practical means of conducting detailed unsteady pressure surveys in flight.

Preliminary design of flight hardware for two-phase fluid research

NASA Technical Reports Server (NTRS)

Hustvedt, D. C.; Oonk, R. L.

1982-01-01

This study defined the preliminary designs of flight software for the Space Shuttle Orbiter for three two-phase fluid research experiments: (1) liquid reorientation - to study the motion of liquid in tanks subjected to small accelerations; (2) pool boiling - to study low-gravity boiling from horizontal cylinders; and (3) flow boiling - to study low-gravity forced flow boiling heat transfer and flow phenomena in a heated horizontal tube. The study consisted of eight major tasks: reassessment of the existing experiment designs, assessment of the Spacelab facility approach, assessment of the individual carry-on approach, selection of the preferred approach, preliminary design of flight hardware, safety analysis, preparation of a development plan, estimates of detailed design, fabrication and ground testing costs. The most cost effective design approach for the experiments is individual carry-ons in the Orbiter middeck. The experiments were designed to fit into one or two middeck lockers. Development schedules for the detailed design, fabrication and ground testing ranged from 15 1/2 to 18 months. Minimum costs (in 1981 dollars) ranged from $463K for the liquid reorientation experiment to $998K for the pool boiling experiment.

third "free flight" of Shuttle Orbiter 101 Spacecraft

NASA Image and Video Library

1977-09-23

S77-28542 (23 Sept 1977) --- The shuttle Orbiter 101 "Enterprise" separates from the NASA 747 carrier aircraft during the third free flight of the Shuttle Approach and Landing Tests (ALT) conducted on September 23, 1977, at the Dryden Flight Research Center (DFRC) in Southern California. The vehicle, with astronauts Fred W. Haise Jr., commander, and C. Gordon Fullerton, pilot, remained in unpowered flight for five-minutes and 34-seconds before landing on the desert land of Edwards Air Force Base.

The X-33 Extended Flight Test Range

NASA Technical Reports Server (NTRS)

Mackall, Dale A.; Sakahara, Robert; Kremer, Steven E.

1998-01-01

Development of an extended test range, with range instrumentation providing continuous vehicle communications, is required to flight-test the X-33, a scaled version of a reusable launch vehicle. The extended test range provides vehicle communications coverage from California to landing at Montana or Utah. This paper provides an overview of the approaches used to meet X-33 program requirements, including using multiple ground stations, and methods to reduce problems caused by reentry plasma radio frequency blackout. The advances used to develop the extended test range show other hypersonic and access-to-space programs can benefit from the development of the extended test range.

Degradation of learned skills: Effectiveness of practice methods on visual approach and landing skill retention

NASA Technical Reports Server (NTRS)

Sitterley, T. E.; Zaitzeff, L. P.; Berge, W. A.

1972-01-01

Flight control and procedural task skill degradation, and the effectiveness of retraining methods were evaluated for a simulated space vehicle approach and landing under instrument and visual flight conditions. Fifteen experienced pilots were trained and then tested after 4 months either without the benefits of practice or with static rehearsal, dynamic rehearsal or with dynamic warmup practice. Performance on both the flight control and procedure tasks degraded significantly after 4 months. The rehearsal methods effectively countered procedure task skill degradation, while dynamic rehearsal or a combination of static rehearsal and dynamic warmup practice was required for the flight control tasks. The quality of the retraining methods appeared to be primarily dependent on the efficiency of visual cue reinforcement.

An improved approach for flight readiness certification: Methodology for failure risk assessment and application examples. Volume 3: Structure and listing of programs

NASA Technical Reports Server (NTRS)

Moore, N. R.; Ebbeler, D. H.; Newlin, L. E.; Sutharshana, S.; Creager, M.

1992-01-01

An improved methodology for quantitatively evaluating failure risk of spaceflight systems to assess flight readiness and identify risk control measures is presented. This methodology, called Probabilistic Failure Assessment (PFA), combines operating experience from tests and flights with engineering analysis to estimate failure risk. The PFA methodology is of particular value when information on which to base an assessment of failure risk, including test experience and knowledge of parameters used in engineering analyses of failure phenomena, is expensive or difficult to acquire. The PFA methodology is a prescribed statistical structure in which engineering analysis models that characterize failure phenomena are used conjointly with uncertainties about analysis parameters and/or modeling accuracy to estimate failure probability distributions for specific failure modes. These distributions can then be modified, by means of statistical procedures of the PFA methodology, to reflect any test or flight experience. Conventional engineering analysis models currently employed for design of failure prediction are used in this methodology. The PFA methodology is described and examples of its application are presented. Conventional approaches to failure risk evaluation for spaceflight systems are discussed, and the rationale for the approach taken in the PFA methodology is presented. The statistical methods, engineering models, and computer software used in fatigue failure mode applications are thoroughly documented.

XV-15 Low-Noise Terminal Area Operations Testing

NASA Technical Reports Server (NTRS)

Edwards, B. D.

1998-01-01

Test procedures related to XV-15 noise tests conducted by NASA-Langley and Bell Helicopter Textron, Inc. are discussed. The tests. which took place during October and November 1995, near Waxahachie, Texas, documented the noise signature of the XV-15 tilt-rotor aircraft at a wide variety of flight conditions. The stated objectives were to: -provide a comprehensive acoustic database for NASA and U.S. Industry -validate noise prediction methodologies, and -develop and demonstrate low-noise flight profiles. The test consisted of two distinct phases. Phase 1 provided an acoustic database for validating analytical noise prediction techniques; Phase 2 directly measured noise contour information at a broad range of operating profiles, with emphasis on minimizing 'approach' noise. This report is limited to a documentation of the test procedures, flight conditions, microphone locations, meteorological conditions, and test personnel used in the test. The acoustic results are not included.

KSC-2014-3694

NASA Image and Video Library

2014-08-29

CAPE CANAVERAL, Fla. – Inside the Delta Operations Center at Cape Canaveral Air Force Station, United Launch Alliance technicians lower the second stage of a Delta IV Heavy rocket following testing in preparation for the unpiloted Exploration Flight Test-1, or EFT-1. The second stage will be moved to the Horizontal Integration Facility at Space Launch Complex 37 for mating with the Delta IV Heavy booster stages. During the mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Kim Shiflett

KSC-2014-3696

NASA Image and Video Library

2014-08-29

CAPE CANAVERAL, Fla. – Inside the Delta Operations Center at Cape Canaveral Air Force Station, United Launch Alliance technicians stand by with a transporter to move the second stage of a Delta IV Heavy rocket following testing in preparation for the unpiloted Exploration Flight Test-1, or EFT-1. The second stage will be transported to the Horizontal Integration Facility at Space Launch Complex 37 for mating with the Delta IV Heavy booster stages. During the mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Kim Shiflett

KSC-2014-3699

NASA Image and Video Library

2014-08-29

CAPE CANAVERAL, Fla. – Inside the Delta Operations Center at Cape Canaveral Air Force Station, United Launch Alliance technicians place the second stage of a Delta IV Heavy rocket on a transporter following testing in preparation for the unpiloted Exploration Flight Test-1, or EFT-1. The second stage will be moved to the Horizontal Integration Facility at Space Launch Complex 37 for mating with the Delta IV Heavy booster stages. During the mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Kim Shiflett

New Approaches in Force-Limited Vibration Testing of Flight Hardware

NASA Technical Reports Server (NTRS)

Kolaini, Ali R.; Kern, Dennis L.

2012-01-01

To qualify flight hardware for random vibration environments the following methods are used to limit the loads in the aerospace industry: (1) Response limiting and notching (2) Simple TDOF model (3) Semi-empirical force limits (4) Apparent mass, etc. and (5) Impedance method. In all these methods attempts are made to remove conservatism due to the mismatch in impedances between the test and the flight configurations of the hardware that are being qualified. Assumption is the hardware interfaces have correlated responses. A new method that takes into account the un-correlated hardware interface responses are described in this presentation.

The development of an augmentor wing jet STOL research aircraft (modified C-8A). Volume 2: Analysis of contractor's flight test

NASA Technical Reports Server (NTRS)

Skavdahl, H.; Patterson, D. H.

1972-01-01

The initial flight test phase of the modified C-8A airplane was conducted. The primary objective of the testing was to establish the basic airworthiness of the research vehicle. This included verification of the structural design and evaluation of the aircraft's systems. Only a minimum amount of performance testing was scheduled; this has been used to provide a preliminary indication of the airplane's performance and flight characteristics for future flight planning. The testing included flutter and loads investigations up to the maximum design speed. The operational characteristics of all systems were assessed including hydraulics, environmental control system, air ducts, the vectoring conical nozzles, and the stability augmentation system (SAS). Approaches to stall were made at three primary flap settings: up, 30 deg and 65 deg, but full stalls were not scheduled. Minimum control speeds and maneuver margins were checked. All takeoffs and landings were conventional, and STOL performance was not scheduled during this phase of the evaluation.

Feasibility of Turing-Style Tests for Autonomous Aerial Vehicle "Intelligence"

NASA Technical Reports Server (NTRS)

Young, Larry A.

2007-01-01

A new approach is suggested to define and evaluate key metrics as to autonomous aerial vehicle performance. This approach entails the conceptual definition of a "Turing Test" for UAVs. Such a "UAV Turing test" would be conducted by means of mission simulations and/or tailored flight demonstrations of vehicles under the guidance of their autonomous system software. These autonomous vehicle mission simulations and flight demonstrations would also have to be benchmarked against missions "flown" with pilots/human-operators in the loop. In turn, scoring criteria for such testing could be based upon both quantitative mission success metrics (unique to each mission) and by turning to analog "handling quality" metrics similar to the well-known Cooper-Harper pilot ratings used for manned aircraft. Autonomous aerial vehicles would be considered to have successfully passed this "UAV Turing Test" if the aggregate mission success metrics and handling qualities for the autonomous aerial vehicle matched or exceeded the equivalent metrics for missions conducted with pilots/human-operators in the loop. Alternatively, an independent, knowledgeable observer could provide the "UAV Turing Test" ratings of whether a vehicle is autonomous or "piloted." This observer ideally would, in the more sophisticated mission simulations, also have the enhanced capability of being able to override the scripted mission scenario and instigate failure modes and change of flight profile/plans. If a majority of mission tasks are rated as "piloted" by the observer, when in reality the vehicle/simulation is fully- or semi- autonomously controlled, then the vehicle/simulation "passes" the "UAV Turing Test." In this regards, this second "UAV Turing Test" approach is more consistent with Turing s original "imitation game" proposal. The overall feasibility, and important considerations and limitations, of such an approach for judging/evaluating autonomous aerial vehicle "intelligence" will be discussed from a theoretical perspective.

Model-Based Verification and Validation of Spacecraft Avionics

NASA Technical Reports Server (NTRS)

Khan, M. Omair; Sievers, Michael; Standley, Shaun

2012-01-01

Verification and Validation (V&V) at JPL is traditionally performed on flight or flight-like hardware running flight software. For some time, the complexity of avionics has increased exponentially while the time allocated for system integration and associated V&V testing has remained fixed. There is an increasing need to perform comprehensive system level V&V using modeling and simulation, and to use scarce hardware testing time to validate models; the norm for thermal and structural V&V for some time. Our approach extends model-based V&V to electronics and software through functional and structural models implemented in SysML. We develop component models of electronics and software that are validated by comparison with test results from actual equipment. The models are then simulated enabling a more complete set of test cases than possible on flight hardware. SysML simulations provide access and control of internal nodes that may not be available in physical systems. This is particularly helpful in testing fault protection behaviors when injecting faults is either not possible or potentially damaging to the hardware. We can also model both hardware and software behaviors in SysML, which allows us to simulate hardware and software interactions. With an integrated model and simulation capability we can evaluate the hardware and software interactions and identify problems sooner. The primary missing piece is validating SysML model correctness against hardware; this experiment demonstrated such an approach is possible.

MMW radar enhanced vision systems: the Helicopter Autonomous Landing System (HALS) and Radar-Enhanced Vision System (REVS) are rotary and fixed wing enhanced flight vision systems that enable safe flight operations in degraded visual environments

NASA Astrophysics Data System (ADS)

Cross, Jack; Schneider, John; Cariani, Pete

2013-05-01

Sierra Nevada Corporation (SNC) has developed rotary and fixed wing millimeter wave radar enhanced vision systems. The Helicopter Autonomous Landing System (HALS) is a rotary-wing enhanced vision system that enables multi-ship landing, takeoff, and enroute flight in Degraded Visual Environments (DVE). HALS has been successfully flight tested in a variety of scenarios, from brown-out DVE landings, to enroute flight over mountainous terrain, to wire/cable detection during low-level flight. The Radar Enhanced Vision Systems (REVS) is a fixed-wing Enhanced Flight Vision System (EFVS) undergoing prototype development testing. Both systems are based on a fast-scanning, threedimensional 94 GHz radar that produces real-time terrain and obstacle imagery. The radar imagery is fused with synthetic imagery of the surrounding terrain to form a long-range, wide field-of-view display. A symbology overlay is added to provide aircraft state information and, for HALS, approach and landing command guidance cuing. The combination of see-through imagery and symbology provides the key information a pilot needs to perform safe flight operations in DVE conditions. This paper discusses the HALS and REVS systems and technology, presents imagery, and summarizes the recent flight test results.

Real-Time Aerodynamic Parameter Estimation without Air Flow Angle Measurements

NASA Technical Reports Server (NTRS)

Morelli, Eugene A.

2010-01-01

A technique for estimating aerodynamic parameters in real time from flight data without air flow angle measurements is described and demonstrated. The method is applied to simulated F-16 data, and to flight data from a subscale jet transport aircraft. Modeling results obtained with the new approach using flight data without air flow angle measurements were compared to modeling results computed conventionally using flight data that included air flow angle measurements. Comparisons demonstrated that the new technique can provide accurate aerodynamic modeling results without air flow angle measurements, which are often difficult and expensive to obtain. Implications for efficient flight testing and flight safety are discussed.

Control Design and Performance Analysis for Autonomous Formation Flight Experimentss

NASA Astrophysics Data System (ADS)

Rice, Caleb Michael

Autonomous Formation Flight is a key approach for reducing greenhouse gas emissions and managing traffic in future high density airspace. Unmanned Aerial Vehicles (UAV's) have made it possible for the physical demonstration and validation of autonomous formation flight concepts inexpensively and eliminates the flight risk to human pilots. This thesis discusses the design, implementation, and flight testing of three different formation flight control methods, Proportional Integral and Derivative (PID); Fuzzy Logic (FL); and NonLinear Dynamic Inversion (NLDI), and their respective performance behavior. Experimental results show achievable autonomous formation flight and performance quality with a pair of low-cost unmanned research fixed wing aircraft and also with a solo vertical takeoff and landing (VTOL) quadrotor.

Seeing the Invisible: Embedding Tests in Code That Cannot be Modified

NASA Technical Reports Server (NTRS)

O'Malley, Owen; Mansouri-Samani, Masoud; Mehlitz, Peter; Penix, John

2005-01-01

The difficulty of characterizing and observing valid software behavior during testing can be very difficult in flight systems. To address this issue, we evaluated several approaches to increasing test observability on the Shuttle Abort Flight Management (SAFM) system. To increase test observability, we added probes into the running system to evaluate the internal state and analyze test data. To minimize the impact of the instrumentation and reduce manual effort, we used Aspect-Oriented Programming (AOP) tools to instrument the source code. We developed and elicited a spectrum of properties, from generic to application specific properties, to be monitored via the instrumentation. To evaluate additional approaches, SAFM was ported to Linux, enabling the use of gcov for measuring test coverage, Valgrind for looking for memory usage errors, and libraries for finding non-normal floating point values. An in-house C++ source code scanning tool was also used to identify violations of SAFM coding standards, and other potentially problematic C++ constructs. Using these approaches with the existing test data sets, we were able to verify several important properties, confirm several problems and identify some previously unidentified issues.

Analysis of a Channeled Centerbody Supersonic Inlet for F-15B Flight Research

NASA Technical Reports Server (NTRS)

Ratnayake, Nalin A.

2010-01-01

The Propulsion Flight Test Fixture at the NASA Dryden Flight Research Center is a unique test platform available for use on the NASA F-15B airplane, tail number 836, as a modular host for a variety of aerodynamics and propulsion research. The first experiment that is to be flown on the test fixture is the Channeled Centerbody Inlet Experiment. The objectives of this project at Dryden are twofold: 1) flight evaluation of an innovative new approach to variable geometry for high-speed inlets, and 2) flight validation of channeled inlet performance prediction by complex computational fluid dynamics codes. The inlet itself is a fixed-geometry version of a mixed-compression, variable-geometry, supersonic in- let developed by TechLand Research, Inc. (North Olmsted, Ohio) to improve the efficiency of supersonic flight at off-nominal conditions. The concept utilizes variable channels in the centerbody section to vary the mass flow of the inlet, enabling efficient operation at a range of flight conditions. This study is particularly concerned with the starting characteristics of the inlet. Computational fluid dynamics studies were shown to align well with analytical predictions, showing the inlet to remain unstarted as designed at the primary test point of Mach 1.5 at an equivalent pressure altitude of 29,500 ft local conditions. Mass-flow-related concerns such as the inlet start problem, as well as inlet efficiency in terms of total pressure loss, are assessed using the flight test geometry.

Fuel-conservative guidance system for powered-lift aircraft

NASA Technical Reports Server (NTRS)

Erzberger, H.; Mclean, J. D.

1979-01-01

A concept for automatic terminal area guidance, comprising two modes of operation, was developed and evaluated in flight tests. In the predictive mode, fuel efficient approach trajectories are synthesized in fast time. In the tracking mode, the synthesized trajectories are reconstructed and tracked automatically. An energy rate performance model derived from the lift, drag, and propulsion system characteristics of the aircraft is used in the synthesis algorithm. The method optimizes the trajectory for the initial aircraft position and wind and temperature profiles encountered during each landing approach. The design theory and the results of simulations and flight tests using the Augmentor Wing Jet STOL Research Aircraft are described.

Characteristics of wake vortex generated by a Boeing 727 jet transport during two-segment and normal ILS approach flight paths

NASA Technical Reports Server (NTRS)

Kurkowski, R. L.; Barber, M. R.; Garodz, L. J.

1976-01-01

A series of flight tests was conducted to evaluate the vortex wake characteristics of a Boeing 727 (B727-200) aircraft during conventional and two-segment ILS approaches. Twelve flights of the B727, which was equipped with smoke generators for vortex marking, were flown and its vortex wake was intentionally encountered by a Lear Jet model 23 (LR-23) and a Piper Twin Comanche (PA-30). Location of the B727 vortex during landing approach was measured using a system of photo-theodolites. The tests showed that at a given separation distance there were no readily apparent differences in the upsets resulting from deliberate vortex encounters during the two types of approaches. Timed mappings of the position of the landing configuration vortices showed that they tended to descend approximately 91 m(300 ft) below the flight path of the B727. The flaps of the B727 have a dominant effect on the character of the trailed wake vortex. The clean wing produces a strong, concentrated vortex but as the flaps are lowered, the vortex system becomes more diffuse. Pilot opinion and roll acceleration data indicate that 4.5 n.mi. would be a minimum separation distance at which roll control of light aircraft (less than 5,670 kg (12,500 lb) could be maintained during parallel encounters of the B727's landing configuration wake. This minimum separation distance is generally in scale with results determined from previous tests of other aircraft using the small roll control criteria.

Aeroservoelastic Modeling of Body Freedom Flutter for Control System Design

NASA Technical Reports Server (NTRS)

Ouellette, Jeffrey

2017-01-01

One of the most severe forms of coupling between aeroelasticity and flight dynamics is an instability called freedom flutter. The existing tools often assume relatively weak coupling, and are therefore unable to accurately model body freedom flutter. Because the existing tools were developed from traditional flutter analysis models, inconsistencies in the final models are not compatible with control system design tools. To resolve these issues, a number of small, but significant changes have been made to the existing approaches. A frequency domain transformation is used with the unsteady aerodynamics to ensure a more physically consistent stability axis rational function approximation of the unsteady aerodynamic model. The aerodynamic model is augmented with additional terms to account for limitations of the baseline unsteady aerodynamic model and to account for the gravity forces. An assumed modes method is used for the structural model to ensure a consistent definition of the aircraft states across the flight envelope. The X-56A stiff wing flight-test data were used to validate the current modeling approach. The flight-test data does not show body-freedom flutter, but does show coupling between the flight dynamics and the aeroelastic dynamics and the effects of the fuel weight.

Recent Loads Calibration Experience With a Delta Wing Airplane

NASA Technical Reports Server (NTRS)

Jenkins, Jerald M.; Kuhl, Albert E.

1977-01-01

Aircraft which are designed for supersonic and hypersonic flight are evolving with delta wing configurations. An integral part of the evolution of all new aircraft is the flight test phase. Included in the flight test phase is an effort to identify and evaluate the loads environment of the aircraft. The most effective way of examining the loads environment is to utilize calibrated strain gages to provide load magnitudes. Using strain gage data to accomplish this has turned out to be anything but a straightforward task. The delta wing configuration has turned out to be a very difficult type of wing structure to calibrate. Elevated structural temperatures result in thermal effects which contaminate strain gage data being used to deduce flight loads. The concept of thermally calibrating a strain gage system is an approach to solving this problem. This paper will address how these problems were approached on a program directed toward measuring loads on the wing of a large, flexible supersonic aircraft. Structural configurations typical of high-speed delta wing aircraft will be examined. The temperature environment will be examined to see how it induces thermal stresses which subsequently cause errors in loads equations used to deduce the flight loads.

Flight-Test Validation and Flying Qualities Evaluation of a Rotorcraft UAV Flight Control System

NASA Technical Reports Server (NTRS)

Mettler, Bernard; Tuschler, Mark B.; Kanade, Takeo

2000-01-01

This paper presents a process of design and flight-test validation and flying qualities evaluation of a flight control system for a rotorcraft-based unmanned aerial vehicle (RUAV). The keystone of this process is an accurate flight-dynamic model of the aircraft, derived by using system identification modeling. The model captures the most relevant dynamic features of our unmanned rotorcraft, and explicitly accounts for the presence of a stabilizer bar. Using the identified model we were able to determine the performance margins of our original control system and identify limiting factors. The performance limitations were addressed and the attitude control system was 0ptimize.d for different three performance levels: slow, medium, fast. The optimized control laws will be implemented in our RUAV. We will first determine the validity of our control design approach by flight test validating our optimized controllers. Subsequently, we will fly a series of maneuvers with the three optimized controllers to determine the level of flying qualities that can be attained. The outcome enable us to draw important conclusions on the flying qualities requirements for small-scale RUAVs.

KSC-2014-3675

NASA Image and Video Library

2014-08-04

CAPE CANAVERAL, Fla. – Preparations are underway to begin mating the United Launch Alliance Delta IV port booster to the core booster inside the Horizontal Integration Facility at Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida. The Delta IV Heavy rocket will launch an uncrewed Orion spacecraft on Exploration Flight Test-1. During the mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Ben Smegelsky

KSC-2014-3676

NASA Image and Video Library

2014-08-04

CAPE CANAVERAL, Fla. – In this close-up photograph, the United Launch Alliance Delta IV port booster is being mated to the core booster inside the Horizontal Integration Facility at Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida. The Delta IV Heavy rocket will launch an uncrewed Orion spacecraft on Exploration Flight Test-1. During the mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Ben Smegelsky

KSC-2014-3910

NASA Image and Video Library

2014-09-12

CAPE CANAVERAL, Fla. – Inside the Horizontal Integration Facility at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida, the second stage of the United Launch Alliance Delta IV Heavy rocket has been mated to the core booster of the three booster stages for the unpiloted Exploration Flight Test-1, or EFT-1. During the mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Daniel Casper

KSC-2014-3902

NASA Image and Video Library

2014-09-12

CAPE CANAVERAL, Fla. – Inside the Horizontal Integration Facility at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida, preparations are underway to mate the second stage of a Delta IV Heavy rocket to the central core booster of the three booster stages for the unpiloted Exploration Flight Test-1, or EFT-1. During the mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Daniel Casper

KSC-2014-3682

NASA Image and Video Library

2014-08-04

CAPE CANAVERAL, Fla. – The United Launch Alliance Delta IV port booster is being mated to the core booster inside the Horizontal Integration Facility at Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida. The Delta IV Heavy rocket will launch an uncrewed Orion spacecraft on Exploration Flight Test-1. During the mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Ben Smegelsky

Modeling, Analysis and Simulation Approaches Used in Development of the National Aeronautics and Space Administration Max Launch Abort System

NASA Technical Reports Server (NTRS)

Yuchnovicz, Daniel E.; Dennehy, Cornelius J.; Schuster, David M.

2011-01-01

The National Aeronautics and Space Administration (NASA) Engineering and Safety Center was chartered to develop an alternate launch abort system (LAS) as risk mitigation for the Orion Project. Its successful flight test provided data for the design of future LAS vehicles. Design of the flight test vehicle (FTV) and pad abort trajectory relied heavily on modeling and simulation including computational fluid dynamics for vehicle aero modeling, 6-degree-of-freedom kinematics models for flight trajectory modeling, and 3-degree-of-freedom kinematics models for parachute force modeling. This paper highlights the simulation techniques and the interaction between the aerodynamics, flight mechanics, and aerodynamic decelerator disciplines during development of the Max Launch Abort System FTV.

Development and in-flight performance of the Mariner 9 spacecraft propulsion system

NASA Technical Reports Server (NTRS)

Evans, D. D.; Cannova, R. D.; Cork, M. J.

1972-01-01

On November 14, 1971, Mariner 9 was decelerated into orbit about Mars by a 1334-newton (300-lbf) liquid bipropellant propulsion system. The development and in-flight performance are described and summarized of this pressure-fed, nitrogen tetroxide/monomethyl hydrazine bipropellant system. The design of all Mariner propulsion subsystems has been predicated upon the premise that simplicity of approach, coupled with thorough qualification and margin-limits testing, is the key to cost-effective reliability. The qualification test program and analytical modeling of the Mariner 9 subsystem are discussed. Since the propulsion subsystem is modular in nature, it was completely checked, serviced, and tested independent of the spacecraft. Proper prediction of in-flight performance required the development of three significant modeling tools to predict and account for nitrogen saturation of the propellant during the six-month coast period and to predict and statistically analyze in-flight data. The flight performance of the subsystem was excellent, as were the performance prediction correlations. These correlations are presented.

ARC-1957-A-22640

NASA Image and Video Library

1957-05-01

NACA Photographer North American F-100A (NACA-200) Super Sabre Airplane take-off. The blowing-tupe boundary-layer control on the leading- and trailing-edge provided large reductions in takeoff and landing approach speeds. Approach speeds were reduced by about 10 knots (Mar 1960). Note: Used in publication in Flight Research at Ames; 57 Years of Development and Validation of Aeronautical Technology NASA SP-1998-3300 fig. 102 and and Memoirs of a Flight Test Engneer NASA SP-2002-4525

Ares I-X Malfunction Turn Range Safety Analysis

NASA Technical Reports Server (NTRS)

Beaty, J. R.

2011-01-01

Ares I-X was the designation given to the flight test version of the Ares I rocket which was developed by NASA (also known as the Crew Launch Vehicle (CLV) component of the Constellation Program). The Ares I-X flight test vehicle achieved a successful flight test on October 28, 2009, from Pad LC-39B at Kennedy Space Center, Florida (KSC). As part of the flight plan approval for the test vehicle, a range safety malfunction turn analysis was performed to support the risk assessment and vehicle destruct criteria development processes. Several vehicle failure scenarios were identified which could have caused the vehicle trajectory to deviate from its normal flight path. The effects of these failures were evaluated with an Ares I-X 6 degrees-of-freedom (6-DOF) digital simulation, using the Program to Optimize Simulated Trajectories Version II (POST2) simulation tool. The Ares I-X simulation analysis provided output files containing vehicle trajectory state information. These were used by other risk assessment and vehicle debris trajectory simulation tools to determine the risk to personnel and facilities in the vicinity of the launch area at KSC, and to develop the vehicle destruct criteria used by the flight test range safety officer in the event of a flight test anomaly of the vehicle. The simulation analysis approach used for this study is described, including descriptions of the failure modes which were considered and the underlying assumptions and ground rules of the study.

Control structural interaction testbed: A model for multiple flexible body verification

NASA Technical Reports Server (NTRS)

Chory, M. A.; Cohen, A. L.; Manning, R. A.; Narigon, M. L.; Spector, V. A.

1993-01-01

Conventional end-to-end ground tests for verification of control system performance become increasingly complicated with the development of large, multiple flexible body spacecraft structures. The expense of accurately reproducing the on-orbit dynamic environment and the attendant difficulties in reducing and accounting for ground test effects limits the value of these tests. TRW has developed a building block approach whereby a combination of analysis, simulation, and test has replaced end-to-end performance verification by ground test. Tests are performed at the component, subsystem, and system level on engineering testbeds. These tests are aimed at authenticating models to be used in end-to-end performance verification simulations: component and subassembly engineering tests and analyses establish models and critical parameters, unit level engineering and acceptance tests refine models, and subsystem level tests confirm the models' overall behavior. The Precision Control of Agile Spacecraft (PCAS) project has developed a control structural interaction testbed with a multibody flexible structure to investigate new methods of precision control. This testbed is a model for TRW's approach to verifying control system performance. This approach has several advantages: (1) no allocation for test measurement errors is required, increasing flight hardware design allocations; (2) the approach permits greater latitude in investigating off-nominal conditions and parametric sensitivities; and (3) the simulation approach is cost effective, because the investment is in understanding the root behavior of the flight hardware and not in the ground test equipment and environment.

Full-Field Reconstruction of Structural Deformations and Loads from Measured Strain Data on a Wing Using the Inverse Finite Element Method

NASA Technical Reports Server (NTRS)

Miller, Eric J.; Manalo, Russel; Tessler, Alexander

2016-01-01

A study was undertaken to investigate the measurement of wing deformation and internal loads using measured strain data. Future aerospace vehicle research depends on the ability to accurately measure the deformation and internal loads during ground testing and in flight. The approach uses the inverse Finite Element Method (iFEM). The iFEM is a robust, computationally efficient method that is well suited for real-time measurement of real-time structural deformation and loads. The method has been validated in previous work, but has yet to be applied to a large-scale test article. This work is in preparation for an upcoming loads test of a half-span test wing in the Flight Loads Laboratory at the National Aeronautics and Space Administration Armstrong Flight Research Center (Edwards, California). The method has been implemented into an efficient MATLAB® (The MathWorks, Inc., Natick, Massachusetts) code for testing different sensor configurations. This report discusses formulation and implementation along with the preliminary results from a representative aerospace structure. The end goal is to investigate the modeling and sensor placement approach so that the best practices can be applied to future aerospace projects.

Determining Damping Trends from a Range of Cable Harness Assemblies on a Launch Vehicle Panel from Test Measurements

NASA Technical Reports Server (NTRS)

Smith, Andrew; Davis, R. Ben; LaVerde, Bruce; Jones, Douglas

2012-01-01

The team of authors at Marshall Space Flight Center (MSFC) has been investigating estimating techniques for the vibration response of launch vehicle panels excited by acoustics and/or aero-fluctuating pressures. Validation of the approaches used to estimate these environments based on ground tests of flight like hardware is of major importance to new vehicle programs. The team at MSFC has recently expanded upon the first series of ground test cases completed in December 2010. The follow on tests recently completed are intended to illustrate differences in damping that might be expected when cable harnesses are added to the configurations under test. This validation study examines the effect on vibroacoustic response resulting from the installation of cable bundles on a curved orthogrid panel. Of interest is the level of damping provided by the installation of the cable bundles and whether this damping could be potentially leveraged in launch vehicle design. The results of this test are compared with baseline acoustic response tests without cables. Damping estimates from the measured response data are made using a new software tool that employs a finite element model (FEM) of the panel in conjunction with advanced optimization techniques. This paper will report on the \\damping trend differences. observed from response measurements for several different configurations of cable harnesses. The data should assist vibroacoustics engineers to make more informed damping assumptions when calculating vibration response estimates when using model based analysis approach. Achieving conservative estimates that have more flight like accuracy is desired. The paper may also assist analysts in determining how ground test data may relate to expected flight response levels. Empirical response estimates may also need to be adjusted if the measured response used as an input to the study came from a test article without flight like cable harnesses.

A New Approach in Force-Limited Vibration Testing of Flight Hardware

NASA Technical Reports Server (NTRS)

Kolaini, Ali R.; Kern, Dennis L.

2012-01-01

The force-limited vibration test approaches discussed in NASA-7004C were developed to reduce overtesting associated with base shake vibration tests of aerospace hardware where the interface responses are excited coherently. This handbook outlines several different methods of specifying the force limits. The rationale for force limiting is based on the disparity between the impedances of typical aerospace mounting structures and the large impedances of vibration test shakers when the interfaces in general are coherently excited. Among these approaches, the semi-empirical method is presently the most widely used method to derive the force limits. The inclusion of the incoherent excitation of the aerospace structures at mounting interfaces has not been accounted for in the past and provides the basis for more realistic force limits for qualifying the hardware using shaker testing. In this paper current methods for defining the force limiting specifications discussed in the NASA handbook are reviewed using data from a series of acoustic and vibration tests. A new approach based on considering the incoherent excitation of the structural mounting interfaces using acoustic test data is also discussed. It is believed that the new approach provides much more realistic force limits that may further remove conservatism inherent in shaker vibration testing not accounted for by methods discussed in the NASA handbook. A discussion on using FEM/BEM analysis to obtain realistic force limits for flight hardware is provided.

Bringing UAVs to the fight: recent army autonomy research and a vision for the future

NASA Astrophysics Data System (ADS)

Moorthy, Jay; Higgins, Raymond; Arthur, Keith

2008-04-01

The Unmanned Autonomous Collaborative Operations (UACO) program was initiated in recognition of the high operational burden associated with utilizing unmanned systems by both mounted and dismounted, ground and airborne warfighters. The program was previously introduced at the 62nd Annual Forum of the American Helicopter Society in May of 20061. This paper presents the three technical approaches taken and results obtained in UACO. All three approaches were validated extensively in contractor simulations, two were validated in government simulation, one was flight tested outside the UACO program, and one was flight tested in Part 2 of UACO. Results and recommendations are discussed regarding diverse areas such as user training and human-machine interface, workload distribution, UAV flight safety, data link bandwidth, user interface constructs, adaptive algorithms, air vehicle system integration, and target recognition. Finally, a vision for UAV As A Wingman is presented.

Use of the flight simulator in the design of a STOL research aircraft.

NASA Technical Reports Server (NTRS)

Spitzer, R. E.; Rumsey, P. C.; Quigley, H. C.

1972-01-01

Piloted simulator tests on the NASA-Ames Flight Simulator for Advanced Aircraft motion base played a major role in guiding the design of the Modified C-8A 'Buffalo' augmentor wing jet flap STOL research airplane. Design results are presented for the flight control systems, lateral-directional SAS, hydraulic systems, and engine and thrust vector controls. Emphasis is given to lateral control characteristics on STOL landing approach, engine-out control and recovery techniques in the powered-lift regime, and operational flight procedures which affected airplane design.

AFFTC commander Brig. Gen. Curtis Bedke experienced a Shuttle approach and landing in NASA's Shuttle Training Aircraft from STS-114 commander Eileen Collins

NASA Image and Video Library

2005-03-29

Brig. Gen. Curtis Bedke, commander of the Air Force Flight Test Center at Edwards Air Force Base, received some first-hand insight on how to fly a Space Shuttle approach and landing, courtesy of NASA astronaut and STS-114 mission commander Eileen Collins. The series of proficiency flights in NASA's modified Grumman Gulfstream-II Shuttle Training Aircraft were in preparation for the STS-114 mission with the shuttle Discovery. Although NASA's Kennedy Space Center in Florida is the primary landing site for Space Shuttle missions, flight crews also practice the shuttle's steep approach and landing at Edwards in case weather or other situations preclude a landing at the Florida site and force a diversion to Edwards AFB.

Development and in-flight performance of the Mariner 9 spacecraft propulsion system

NASA Technical Reports Server (NTRS)

Evans, D. D.; Cannova, R. D.; Cork, M. J.

1973-01-01

On November 14, 1971, Mariner 9 was decelerated into orbit about Mars by a 1334 N (300 lbf) liquid bipropellant propulsion system. This paper describes and summarizes the development and in-flight performance of this pressure-fed, nitrogen tetroxide/monomethyl hydrazine bipropellant system. The design of all Mariner propulsion subsystems has been predicted upon the premise that simplicity of approach, coupled with thorough qualification and margin-limits testing, is the key to cost-effective reliability. The qualification test program and analytical modeling are also discussed. Since the propulsion subsystem is modular in nature, it was completely checked, serviced, and tested independent of the spacecraft. Proper prediction of in-flight performance required the development of three significant modeling tools to predict and account for nitrogen saturation of the propellant during the six-month coast period and to predict and statistically analyze in-flight data.

KSC-2014-3695

NASA Image and Video Library

2014-08-29

CAPE CANAVERAL, Fla. – Inside the Delta Operations Center at Cape Canaveral Air Force Station, United Launch Alliance technicians place the second stage of a Delta IV Heavy rocket on a support fixture following testing in preparation for the unpiloted Exploration Flight Test-1, or EFT-1. The second stage will be placed on a transporter for the move to the Horizontal Integration Facility at Space Launch Complex 37 for mating with the Delta IV Heavy booster stages. During the mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Kim Shiflett

Assessment of noise in the airplane cabin environment.

PubMed

Zevitas, Christopher D; Spengler, John D; Jones, Byron; McNeely, Eileen; Coull, Brent; Cao, Xiaodong; Loo, Sin Ming; Hard, Anna-Kate; Allen, Joseph G

2018-03-15

To measure sound levels in the aircraft cabin during different phases of flight. Sound level was measured on 200 flights, representing six aircraft groups using continuous monitors. A linear mixed-effects model with random intercept was used to test for significant differences in mean sound level by aircraft model and across each flight phase as well as by flight phase, airplane type, measurement location and proximity to engine noise. Mean sound levels across all flight phases and aircraft groups ranged from 37.6 to >110 dB(A) with a median of 83.5 dB(A). Significant differences in noise levels were also observed based on proximity to the engines and between aircraft with fuselage- and wing mounted engines. Nine flights (4.5%) exceeded the recommended 8-h TWA exposure limit of 85 dB(A) by the NIOSH and ACGIH approach, three flights (1.5%) exceeded the 8-h TWA action level of 85 dB(A) by the OSHA approach, and none of the flights exceeded the 8-h TWA action level of 90 dB(A) by the OSHA PEL approach. Additional characterization studies, including personal noise dosimetry, are necessary to document accurate occupational exposures in the aircraft cabin environment and identify appropriate response actions. FAA should consider applying the more health-protective NIOSH/ACGIH occupational noise recommendations to the aircraft cabin environment.

Helicopter flight test demonstration of differential GPS

NASA Technical Reports Server (NTRS)

Denaro, R. P.; Beser, J.

1985-01-01

An off-line post-mission processing facility is being established by NASA Ames Research Center to analyze differential GPS flight tests. The current and future differential systems are described, comprising an airborne segment in an SH-3 helicopter, a GPS ground reference station, and a tracking system. The post-mission processing system provides for extensive measurement analysis and differential computation. Both differential range residual corrections and navigation corrections are possible. Some preliminary flight tests were conducted in a landing approach scenario and statically. Initial findings indicate the possible need for filter matching between airborne and ground systems (if used in a navigation correction technique), the advisability of correction smoothing before airborne incorporation, and the insensitivity of accuracy to either of the differential techniques or to update rates.

Noise measurements for a twin-engine commercial jet aircraft during 3 deg approaches and level flyovers

NASA Technical Reports Server (NTRS)

Hastings, E. C., Jr.; Shanks, R. E.; Mueller, A. W.

1976-01-01

Noise measurements have been made with a twin-engine commercial jet aircraft making 3 deg approaches and level flyovers. The flight-test data showed that, in the standard 3 deg approach configuration with 40 deg flaps, effective perceived noise level (EPNL) had a value of 109.5 effective perceived noise decibels (EPNdB). This result was in agreement with unpublished data obtained with the same type of aircraft during noise certification tests; the 3 deg approaches made with 30 deg flaps and slightly reduced thrust reduced the EPNL value by 1 EPNdB. Extended center-line noise determined during the 3 deg approaches with 40 deg flaps showed that the maximum reference A-weighted sound pressure level (LA,max)ref varied from 100.0 A-weighted decibels 2.01 km (108 n. mi.) from the threshold to 87.4 db(A) at 6.12 km (3.30 n. mi.) from the threshold. These test values were about 3 db(A) higher than estimates used for comparison. The test data along the extended center line during approaches with 30 deg flaps were 1 db(A) lower than those for approaches with 40 deg flaps. Flight-test data correlating (LA,max)ref with thrust at altitudes of 122 m (400 ft) and 610 m (2000 ft) were in agreement with reference data used for comparison.

HyBoLT Flight Experiment

NASA Technical Reports Server (NTRS)

Chen, Fang-Jeng (Frank); Berry, Scott A.

2010-01-01

HyBoLT was a Hypersonic Boundary Layer Transition flight experiment funded by the Hypersonics Project of the Fundamental Aeronautics Program in NASA's Aeronautics Research Mission Directorate. The HyBoLT test article mounted on the top of the ALV X-1 rocket was launched from Virginia's Wallops Island on August 22, 2008. Unfortunately a problem in the rocket's flight control system caused the vehicle to veer off the designed flight course. Launch officials activated a self-destruct mechanism in the rocket's nose cone after 20 seconds into flight. This report is a closeout document about the HyBoLT flight experiment. Details are provided of the objectives and approach associated with this experimental program as well as the 20 seconds flight data acquired before the vehicle was destroyed.

Analysis and flight evaluation of a small, fixed-wing aircraft equipped with hinged plate spoilers

NASA Technical Reports Server (NTRS)

Olcott, J. W.; Sackel, E.; Ellis, D. R.

1981-01-01

The results of a four phase effort to evaluate the application of hinged plate spoilers/dive brakes to a small general aviation aircraft are presented. The test vehicle was a single engine light aircraft modified with an experimental set of upper surface spoilers and lower surface dive brakes similar to the type used on sailplanes. The lift, drag, stick free stability, trim, and dynamic response characteristics of four different spoiler/dive brake configurations were determined. Tests also were conducted, under a wide range of flight conditions and with pilots of various experience levels, to determine the most favorable methods of spoiler control and to evaluate how spoilers might best be used during the approach and landing task. The effects of approach path angle, approach airspeed, and pilot technique using throttle/spoiler integrated control were investigated for day, night, VFR, and IFR approaches and landings. The test results indicated that spoilers offered significant improvements in the vehicle's performance and flying qualities for all elements of the approach and landing task, provided a suitable method of control was available.

Orbiter thermal protection system

NASA Technical Reports Server (NTRS)

Dotts, R. L.; Curry, D. M.; Tillian, D. J.

1985-01-01

The major material and design challenges associated with the orbiter thermal protection system (TPS), the various TPS materials that are used, the different design approaches associated with each of the materials, and the performance during the flight test program are described. The first five flights of the Orbiter Columbia and the initial flight of the Orbiter Challenger provided the data necessary to verify the TPS thermal performance, structural integrity, and reusability. The flight performance characteristics of each TPS material are discussed, based on postflight inspections and postflight interpretation of the flight instrumentation data. Flights to date indicate that the thermal and structural design requirements for the orbiter TPS are met and that the overall performance is outstanding.

Effectively Transforming IMC Flight into VMC Flight: An SVS Case Study

NASA Technical Reports Server (NTRS)

Glaab, Louis J.; Hughes, Monic F.; Parrish, Russell V.; Takallu, Mohammad A.

2006-01-01

A flight-test experiment was conducted using the NASA LaRC Cessna 206 aircraft. Four primary flight and navigation display concepts, including baseline and Synthetic Vision System (SVS) concepts, were evaluated in the local area of Roanoke Virginia Airport, flying visual and instrument approach procedures. A total of 19 pilots, from 3 pilot groups reflecting the diverse piloting skills of the GA population, served as evaluation pilots. Multi-variable Discriminant Analysis was applied to three carefully selected and markedly different operating conditions with conventional instrumentation to provide an extension of traditional analysis methods as well as provide an assessment of the effectiveness of SVS displays to effectively transform IMC flight into VMC flight.

MLS Multipath Studies. Phase 3. Volume II. Development and Valiadation of Model for MLS Techniques.

DTIC Science & Technology

1980-02-07

2-40 2-32 Coherent interference phenomena encountered during TRSB field tests at JFK airport . 2-41 2-33 JFK airport environment near MLS elevation...24 4-8 Comparison of DMLS simulation and flight test on -380 radial at 2000 feet at JFK airport . 4-26 4-9 Comparison of DMLS simulation and flight...test on +380 radial at 2000 feet at JFK airport . 4-28 xv ( 4-10 Comparison of simulation with DMLS JFK centerline approach data. 4-29 4-11 DMLS "clean

Orbiter windward surface entry Heating: Post-orbital flight test program update

NASA Technical Reports Server (NTRS)

Harthun, M. H.; Blumer, C. B.; Miller, B. A.

1983-01-01

Correlations of orbiter windward surface entry heating data from the first five flights are presented with emphasis on boundary layer transition and the effects of catalytic recombination. Results show that a single roughness boundary layer transition correlation developed for spherical element trips works well for the orbiter tile system. Also, an engineering approach for predicting heating in nonequilibrium flow conditions shows good agreement with the flight test data in the time period of significant heating. The results of these correlations, when used to predict orbiter heating for a high cross mission, indicate that the thermal protection system on the windward surface will perform successfully in such a mission.

Flight test trajectory control analysis

NASA Technical Reports Server (NTRS)

Walker, R.; Gupta, N.

1983-01-01

Recent extensions to optimal control theory applied to meaningful linear models with sufficiently flexible software tools provide powerful techniques for designing flight test trajectory controllers (FTTCs). This report describes the principal steps for systematic development of flight trajectory controllers, which can be summarized as planning, modeling, designing, and validating a trajectory controller. The techniques have been kept as general as possible and should apply to a wide range of problems where quantities must be computed and displayed to a pilot to improve pilot effectiveness and to reduce workload and fatigue. To illustrate the approach, a detailed trajectory guidance law is developed and demonstrated for the F-15 aircraft flying the zoom-and-pushover maneuver.

Description and flight tests of an oculometer

NASA Technical Reports Server (NTRS)

Middleton, D. B.; Hurt, G. J., Jr.; Wise, M. A.; Holt, J. D.

1977-01-01

A remote sensing oculometer was successfully operated during flight tests with a NASA experimental Twin Otter aircraft at the Langley Research Center. Although the oculometer was designed primarily for the laboratory, it was able to track the pilot's eye-point-of-regard (lookpoint) consistently and unobtrusively in the flight environment. The instantaneous position of the lookpoint was determined to within approximately 1 deg. Data were recorded on both analog and video tape. The video data consisted of continuous scenes of the aircraft's instrument display and a superimposed white dot (simulating the lookpoint) dwelling on an instrument or moving from instrument to instrument as the pilot monitored the display information during landing approaches.

A Risk-Based Approach for Aerothermal/TPS Analysis and Testing

NASA Technical Reports Server (NTRS)

Wright, Michael J.; Grinstead, Jay H.; Bose, Deepak

2007-01-01

The current status of aerothermal and thermal protection system modeling for civilian entry missions is reviewed. For most such missions, the accuracy of our simulations is limited not by the tools and processes currently employed, but rather by reducible deficiencies in the underlying physical models. Improving the accuracy of and reducing the uncertainties in these models will enable a greater understanding of the system level impacts of a particular thermal protection system and of the system operation and risk over the operational life of the system. A strategic plan will be laid out by which key modeling deficiencies can be identified via mission-specific gap analysis. Once these gaps have been identified, the driving component uncertainties are determined via sensitivity analyses. A Monte-Carlo based methodology is presented for physics-based probabilistic uncertainty analysis of aerothermodynamics and thermal protection system material response modeling. These data are then used to advocate for and plan focused testing aimed at reducing key uncertainties. The results of these tests are used to validate or modify existing physical models. Concurrently, a testing methodology is outlined for thermal protection materials. The proposed approach is based on using the results of uncertainty/sensitivity analyses discussed above to tailor ground testing so as to best identify and quantify system performance and risk drivers. A key component of this testing is understanding the relationship between the test and flight environments. No existing ground test facility can simultaneously replicate all aspects of the flight environment, and therefore good models for traceability to flight are critical to ensure a low risk, high reliability thermal protection system design. Finally, the role of flight testing in the overall thermal protection system development strategy is discussed.

Saberliner flight test for airborne wind shear forward looking detection and avoidance radar systems

NASA Technical Reports Server (NTRS)

Mathews, Bruce D.

1991-01-01

Westinghouse conducted a flight test with its Sabreliner AN/APG-68 instrumented radar to assess the urban discrete/ground moving vehicle clutter environment. Glideslope approaches were flown into Washington National, BWI, and Georgetown, Delaware, airports employing radar mode timing, waveform, and processing configurations plausible for microburst windshear avoidance. The perceptions, both general and specific, of the clutter environment furnish an empirical foundation for beginning low false alarm detection algorithm development.

A pilot's opinion - VTOL control design requirements for the instrument approach task.

NASA Technical Reports Server (NTRS)

Patton, J. M., Jr.

1972-01-01

This paper presents pilot opinion supported by test data concerning flight control and display concepts and control system design requirements for VTOL aircraft in the instrument approach task. Material presented is drawn from research flights in the following aircraft: Dornier DO-31, Short SC-1, LTV XC-142A, and Boeing-Vertol CH-46. The control system concepts and mechanizations employed in the above aircraft are discussed, and the effect of control system augmentation is shown on performance. Operational procedures required in the instrument approach task are described, with comments on need for automation and combining of control functions.

KSC-2014-3688

NASA Image and Video Library

2014-08-04

CAPE CANAVERAL, Fla. – A United Launch Alliance, or ULA, technician monitors the progress as the Delta IV port booster is mated to the core booster inside the Horizontal Integration Facility at Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida. The ULA Delta IV Heavy rocket will launch an uncrewed Orion spacecraft on Exploration Flight Test-1. During the mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Ben Smegelsky

KSC-2014-3680

NASA Image and Video Library

2014-08-04

CAPE CANAVERAL, Fla. – United Launch Alliance, or ULA, technicians monitor the progress as the Delta IV port booster is mated to the core booster inside the Horizontal Integration Facility at Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida. The ULA Delta IV Heavy rocket will launch an uncrewed Orion spacecraft on Exploration Flight Test-1. During the mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Ben Smegelsky

KSC-2014-3683

NASA Image and Video Library

2014-08-04

CAPE CANAVERAL, Fla. – United Launch Alliance, or ULA, technicians monitor the progress as the Delta IV port booster is mated to the core booster inside the Horizontal Integration Facility at Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida. The ULA Delta IV Heavy rocket will launch an uncrewed Orion spacecraft on Exploration Flight Test-1. During the mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Ben Smegelsky

KSC-2014-3908

NASA Image and Video Library

2014-09-12

CAPE CANAVERAL, Fla. – Inside the Horizontal Integration Facility at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida, a United Launch Alliance technician on a scissor lift monitors the progress as the second stage of a Delta IV Heavy rocket is mated to the central core booster of the three booster stages for the unpiloted Exploration Flight Test-1, or EFT-1. During the mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Daniel Casper

KSC-2014-3678

NASA Image and Video Library

2014-08-04

CAPE CANAVERAL, Fla. – United Launch Alliance, or ULA, technicians monitor the progress as the Delta IV port booster is mated to the core booster inside the Horizontal Integration Facility at Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida. The ULA Delta IV Heavy rocket will launch an uncrewed Orion spacecraft on Exploration Flight Test-1. During the mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Ben Smegelsky

KSC-2014-3681

NASA Image and Video Library

2014-08-04

CAPE CANAVERAL, Fla. – United Launch Alliance, or ULA, technicians monitor the progress as the Delta IV port booster is mated to the core booster inside the Horizontal Integration Facility at Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida. The ULA Delta IV Heavy rocket will launch an uncrewed Orion spacecraft on Exploration Flight Test-1. During the mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Ben Smegelsky

KSC-2014-3677

NASA Image and Video Library

2014-08-04

CAPE CANAVERAL, Fla. – United Launch Alliance, or ULA, technicians monitor the progress as the Delta IV port booster is mated to the core booster inside the Horizontal Integration Facility at Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida. The ULA Delta IV Heavy rocket will launch an uncrewed Orion spacecraft on Exploration Flight Test-1. During the mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Ben Smegelsky

KSC-2014-3679

NASA Image and Video Library

2014-08-04

CAPE CANAVERAL, Fla. – United Launch Alliance, or ULA, technicians monitor the progress as the Delta IV port booster is mated to the core booster inside the Horizontal Integration Facility at Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida. The ULA Delta IV Heavy rocket will launch an uncrewed Orion spacecraft on Exploration Flight Test-1. During the mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Ben Smegelsky

KSC-2014-3906

NASA Image and Video Library

2014-09-12

CAPE CANAVERAL, Fla. – Inside the Horizontal Integration Facility at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida, United Launch Alliance technicians monitor the progress as the second stage of a Delta IV Heavy rocket is mated to the central core booster of the three booster stages for the unpiloted Exploration Flight Test-1, or EFT-1. During the mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Daniel Casper

KSC-2014-3907

NASA Image and Video Library

2014-09-12

CAPE CANAVERAL, Fla. – Inside the Horizontal Integration Facility at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida, a United Launch Alliance technician on a scissor lift monitors the progress as the second stage of a Delta IV Heavy rocket is mated to the central core booster of the three booster stages for the unpiloted Exploration Flight Test-1, or EFT-1. During the mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Daniel Casper

KSC-2014-3684

NASA Image and Video Library

2014-08-04

CAPE CANAVERAL, Fla. – United Launch Alliance, or ULA, technicians monitor the progress as the Delta IV port booster is mated to the core booster inside the Horizontal Integration Facility at Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida. The ULA Delta IV Heavy rocket will launch an uncrewed Orion spacecraft on Exploration Flight Test-1. During the mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Ben Smegelsky

KSC-2014-3700

NASA Image and Video Library

2014-08-29

CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station, United Launch Alliance technicians transport the second stage of a Delta IV Heavy rocket to the Horizontal Integration Facility at Space Launch Complex 37. The second stage then will be mated with the Delta IV Heavy booster stages in preparation for the unpiloted Exploration Flight Test-1, or EFT-1. During the mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Kim Shiflett

KSC-2014-3687

NASA Image and Video Library

2014-08-04

CAPE CANAVERAL, Fla. – United Launch Alliance, or ULA, technicians monitor the progress as the Delta IV port booster is mated to the core booster inside the Horizontal Integration Facility at Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida. The ULA Delta IV Heavy rocket will launch an uncrewed Orion spacecraft on Exploration Flight Test-1. During the mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Ben Smegelsky

Flight investigation of a four-dimensional terminal area guidance system for STOL aircraft

NASA Technical Reports Server (NTRS)

Neuman, F.; Hardy, G. H.

1981-01-01

A series of flight tests and fast-time simulations were conducted, using the augmentor wing jet STOL research aircraft and the STOLAND 4D-RNAV system to add to the growing data base of 4D-RNAV system performance capabilities. To obtain statistically meaningful data a limited amount of flight data were supplemented by a statistically significant amount of data obtained from fast-time simulation. The results of these tests are reported. Included are comparisons of the 4D-RNAV estimated winds with actual winds encountered in flight, as well as data on along-track navigation and guidance errors, and time-of-arrival errors at the final approach waypoint. In addition, a slight improvement of the STOLAND 4D-RNAV system is proposed and demonstrated, using the fast-time simulation.

Fuel-conservative guidance system for powered-lift aircraft

NASA Technical Reports Server (NTRS)

Erzberger, H.; Mclean, J. D.

1979-01-01

A concept for automatic terminal-area guidance, comprising two modes of operation, has been developed and evaluated in flight tests. In the first or predictive mode, fuel-efficient approach trajectories are synthesized in fast time. In the second or tracking mode, the synthesized trajectories are reconstructed and tracked automatically. An energy rate performance model derived from the lift, drag, and propulsion-system characteristics of the aircraft is used in the synthesis algorithm. The method optimizes the trajectory for the initial aircraft position and wind and temperature profiles encountered during each landing approach. The paper describes the design theory and discusses the results of simulations and flight tests using the Augmentor Wing Jet STOL Research Aircraft.

Modeling methodology for MLS range navigation system errors using flight test data

NASA Technical Reports Server (NTRS)

Karmali, M. S.; Phatak, A. V.

1982-01-01

Flight test data was used to develop a methodology for modeling MLS range navigation system errors. The data used corresponded to the constant velocity and glideslope approach segment of a helicopter landing trajectory. The MLS range measurement was assumed to consist of low frequency and random high frequency components. The random high frequency component was extracted from the MLS range measurements. This was done by appropriate filtering of the range residual generated from a linearization of the range profile for the final approach segment. This range navigation system error was then modeled as an autoregressive moving average (ARMA) process. Maximum likelihood techniques were used to identify the parameters of the ARMA process.

An improved approach for flight readiness certification: Probabilistic models for flaw propagation and turbine blade failure. Volume 1: Methodology and applications

NASA Technical Reports Server (NTRS)

Moore, N. R.; Ebbeler, D. H.; Newlin, L. E.; Sutharshana, S.; Creager, M.

1992-01-01

An improved methodology for quantitatively evaluating failure risk of spaceflight systems to assess flight readiness and identify risk control measures is presented. This methodology, called Probabilistic Failure Assessment (PFA), combines operating experience from tests and flights with analytical modeling of failure phenomena to estimate failure risk. The PFA methodology is of particular value when information on which to base an assessment of failure risk, including test experience and knowledge of parameters used in analytical modeling, is expensive or difficult to acquire. The PFA methodology is a prescribed statistical structure in which analytical models that characterize failure phenomena are used conjointly with uncertainties about analysis parameters and/or modeling accuracy to estimate failure probability distributions for specific failure modes. These distributions can then be modified, by means of statistical procedures of the PFA methodology, to reflect any test or flight experience. State-of-the-art analytical models currently employed for designs failure prediction, or performance analysis are used in this methodology. The rationale for the statistical approach taken in the PFA methodology is discussed, the PFA methodology is described, and examples of its application to structural failure modes are presented. The engineering models and computer software used in fatigue crack growth and fatigue crack initiation applications are thoroughly documented.

An improved approach for flight readiness certification: Probabilistic models for flaw propagation and turbine blade failure. Volume 2: Software documentation

NASA Technical Reports Server (NTRS)

Moore, N. R.; Ebbeler, D. H.; Newlin, L. E.; Sutharshana, S.; Creager, M.

1992-01-01

An improved methodology for quantitatively evaluating failure risk of spaceflights systems to assess flight readiness and identify risk control measures is presented. This methodology, called Probabilistic Failure Assessment (PFA), combines operating experience from tests and flights with analytical modeling of failure phenomena to estimate failure risk. The PFA methodology is of particular value when information on which to base an assessment of failure risk, including test experience and knowledge of parameters used in analytical modeling, is expensive or difficult to acquire. The PFA methodology is a prescribed statistical structure in which analytical models that characterize failure phenomena are used conjointly with uncertainties about analysis parameters and/or modeling accuracy to estimate failure probability distributions for specific failure modes. These distributions can then be modified, by means of statistical procedures of the PFA methodology, to reflect any test or flight experience. State-of-the-art analytical models currently employed for design, failure prediction, or performance analysis are used in this methodology. The rationale for the statistical approach taken in the PFA methodology is discussed, the PFA methodology is described, and examples of its application to structural failure modes are presented. The engineering models and computer software used in fatigue crack growth and fatigue crack initiation applications are thoroughly documented.

The First Flight Decision for New Human Spacecraft Vehicles - A General Approach

NASA Technical Reports Server (NTRS)

Schaible, Dawn M.; Sumrall, John Phillip

2011-01-01

Determining when it is safe to fly a crew on a launch vehicle/spacecraft for the first time, especially when the test flight is a part of the overall system certification process, has long been a challenge for program decision makers. The decision on first flight is ultimately the judgment of the program and agency management in conjunction with the design and operations team. To aid in this decision process, a NASA team undertook the task to develop a generic framework for evaluating whether any given program or commercial provider has sufficiently complete and balanced plans in place to allow crewmembers to safely fly on human spaceflight systems for the first time. It was the team s goal to establish a generic framework that could easily be applied to any new system, although the system design and intended mission would require specific assessment. Historical data shows that there are multiple approaches that have been successful in first flight with crew. These approaches have always been tailored to the specific system design, mission objectives, and launch environment. Because specific approaches may vary significantly between different system designs and situations, prescriptive instructions or thorough checklists cannot be provided ahead of time. There are, however, certain general approaches that should be applied in thinking through the decision for first flight. This paper addresses some of the most important factors to consider when developing a new system or evaluating an existing system for whether or not it is safe to fly humans to/from space. In the simplest terms, it is time to fly crew for the first time when it is safe to do so and the benefit of the crewed flight is greater than the residual risk. This is rarely a straight-forward decision. The paper describes the need for experience, sound judgment, close involvement of the technical and management teams, and established decision processes. In addition, the underlying level of confidence the manager has in making the decision will also be discussed. By applying the outlined thought processes and approaches to a specific design, test program and mission objectives, a project team will be better able to focus the debate and discussion on critical areas for consideration and added scrutiny -- allowing decision makers to adequately address the first crewed flight decision.

STS-1 landing at Edwards - first orbital mission

NASA Technical Reports Server (NTRS)

1981-01-01

The first flight of a space shuttle into space and back occurred from April 12 to April 14, 1981. After years of testing of the space shuttle Columbia and training the astronauts in simulators, the orbiter lifted off into space on the 12th, boosted by the seven million pounds of thrust supplied by its solid-propellant rockets and liquid-hydrogen engines. The flight, one of four Orbital Flight Tests of Columbia, served as a two-day demonstration of the first reusable, piloted spacecraft's ability to go into orbit and return safely to Earth. Columbia carried as its main payload a Developmental Flight Instrumentation pallet with instruments to record pressures, temperatures, and levels of acceleration at various points on the vehicle during launch, flight, and landing. One of many cameras aboard--a remote television camera--revealed some of the thermal protection tiles had disengaged during launch. As Columbia reentered the atmosphere from space at Mach 24 (24 times the speed of sound) after 36 orbits, aerodynamic heating built up to over 3,000 degrees Fahrenheit, causing some concern during the moments when ionized gases disrupted radio communication. But at 188,000 feet and Mach 10, mission commander John W. Young and pilot Robert L. Crippen reported that the orbiter was performing as expected. After a series of maneuvers to reduce speed, the mission commander and pilot prepared to land. In flight, Young and Crippen tested the spacecraft's on-board systems, fired the orbital maneuvering system for changing orbits, employed the reaction control system for controlling attitude, and opened and closed the payload doors. Columbia was the first reusable, piloted spacecraft, the first piloted lifting-reentry vehicle, and the first piloted spacecraft without a crew escape system. Energy management for the space shuttles was based on previous experience with the X-15 at NASA's Flight Research Center (which had become the Dryden Flight Research Center in 1976). Landing the shuttles without power--and therefore without the weight penalty of an additional engine and fuel--was based on previous experience at the Flight Research Center with piloted lifting bodies that also landed without power, as had the X-15s. Dryden and Edwards Air Force Base (AFB) had also hosted the approach and landing tests of the shuttle prototype Enterprise in 1977 and had tested the computers used for the shuttles' flight control systems in the F-8 Digital Fly-By-Wire aircraft, which also contributed to the solution of a dangerous pilot induced oscillation that occurred on the final approach and landing test. In this clip Young and Crippen fly the orbiter Columbia to a picture-perfect, unpowered landing on the dry lakebed runway 23 at Edwards AFB, CA, after it's first orbital flight, which ended on April 14.

Reentry Motion and Aerodynamics of the MUSES-C Sample Return Capsule

NASA Astrophysics Data System (ADS)

Ishii, Nobuaki; Yamada, Tetsuya; Hiraki, Koju; Inatani, Yoshifumi

The Hayabusa spacecraft (MUSES-C) carries a small capsule for bringing asteroid samples back to the earth. The initial spin rate of the reentry capsule together with the flight path angle of the reentry trajectory is a key parameter for the aerodynamic motion during the reentry flight. The initial spin rate is given by the spin-release mechanism attached between the capsule and the mother spacecraft, and the flight path angle can be modified by adjusting the earth approach orbit. To determine the desired values of both parameters, the attitude motion during atmospheric flight must be clarified, and angles of attack at the maximum dynamic pressure and the parachute deployment must be assessed. In previous studies, to characterize the aerodynamic effects of the reentry capsule, several wind-tunnel tests were conducted using the ISAS high-speed flow test facilities. In addition to the ground test data, the aerodynamic properties in hypersonic flows were analyzed numerically. Moreover, these data were made more accurate using the results of balloon drop tests. This paper summarized the aerodynamic properties of the reentry capsule and simulates the attitude motion of the full-configuration capsule during atmospheric flight in three dimensions with six degrees of freedom. The results show the best conditions for the initial spin rates and flight path angles of the reentry trajectory.

Application of Calspan pitch rate control system to the Space Shuttle for approach and landing

NASA Technical Reports Server (NTRS)

Weingarten, N. C.; Chalk, C. R.

1983-01-01

A pitch rate control system designed for use in the shuttle during approach and landing was analyzed and compared with a revised control system developed by NASA and the existing OFT control system. The design concept control system uses filtered pitch rate feedback with proportional plus integral paths in the forward loop. Control system parameters were designed as a function of flight configuration. Analysis included time and frequency domain techniques. Results indicate that both the Calspan and NASA systems significantly improve the flying qualities of the shuttle over the OFT. Better attitude and flight path control and less time delay are the primary reasons. The Calspan system is preferred because of reduced time delay and simpler mechanization. Further testing of the improved flight control systems in an in-flight simulator is recommended.

The Development of the Ares I-X Flight Test

NASA Technical Reports Server (NTRS)

Ess, Robert H.

2008-01-01

The National Aeronautics and Space Administration (NASA) Constellation Program (CxP) has identified a series of tests to provide insight into the design and development of the Ares I Crew Launch Vehicle (CLV) and the Orion Crew Exploration Vehicle (CEV). Ares I-X was created as the first suborbital development flight test to help meet CxP objectives. The Ares I-X flight vehicle is an early operational model of Ares, with specific emphasis on Ares I and ground operation characteristics necessary to meet Ares I-X flight test objectives. Ares I-X will encompass the design and construction of an entire system that includes the Flight Test Vehicle (FTV) and associated operations. The FTV will be a test model based on the Ares I design. Select design features will be incorporated in the FTV design to emulate the operation of the CLV in order to meet the flight test objectives. The operations infrastructure and processes will be customized for Ares I-X, while still providing data to inform the developers of the launch processing system for Ares/Orion. The FTV is comprised of multiple elements and components that will be developed at different locations. The components will be delivered to the launch/assembly site, Kennedy Space Center (KSC), for assembly of the elements and components into an integrated, flight-ready, launch vehicle. The FTV will fly a prescribed trajectory in order to obtain the necessary data to meet the objectives. Ares I-X will not be commanded or controlled from the ground during flight, but the FTV will be equipped with telemetry systems, a data recording capability and a flight termination system (FTS). The in-flight part of the test includes a trajectory to simulate maximum dynamic pressure during flight and perform a stage separation representative of the CLV. The in-flight test also includes separation of the Upper Stage Simulator (USS) from the First Stage and recovery of the First Stage. The data retrieved from the flight test will be analyzed and used in the design and development of the Ares I vehicle. This paper will discuss the challenges in developing a new launch vehicle in a very short timeframe. The duration from formal Authority to Proceed to launch is 32 months with launch scheduled for April, 2009. The discussion will include changes to organizational structure, system engineering approaches, and early lessons learned for a fast tracked and highly visible project.

Approaching birds with drones: first experiments and ethical guidelines

PubMed Central

Vas, Elisabeth; Lescroël, Amélie; Duriez, Olivier; Boguszewski, Guillaume; Grémillet, David

2015-01-01

Unmanned aerial vehicles, commonly called drones, are being increasingly used in ecological research, in particular to approach sensitive wildlife in inaccessible areas. Impact studies leading to recommendations for best practices are urgently needed. We tested the impact of drone colour, speed and flight angle on the behavioural responses of mallards Anas platyrhynchos in a semi-captive situation, and of wild flamingos (Phoenicopterus roseus) and common greenshanks (Tringa nebularia) in a wetland area. We performed 204 approach flights with a quadricopter drone, and during 80% of those we could approach unaffected birds to within 4 m. Approach speed, drone colour and repeated flights had no measurable impact on bird behaviour, yet they reacted more to drones approaching vertically. We recommend launching drones farther than 100 m from the birds and adjusting approach distance according to species. Our study is a first step towards a sound use of drones for wildlife research. Further studies should assess the impacts of different drones on other taxa, and monitor physiological indicators of stress in animals exposed to drones according to group sizes and reproductive status. PMID:25652220

Flight evaluation of two-segment approaches using area navigation guidance equipment

NASA Technical Reports Server (NTRS)

Schwind, G. K.; Morrison, J. A.; Nylen, W. E.; Anderson, E. B.

1976-01-01

A two-segment noise abatement approach procedure for use on DC-8-61 aircraft in air carrier service was developed and evaluated. The approach profile and procedures were developed in a flight simulator. Full guidance is provided throughout the approach by a Collins Radio Company three-dimensional area navigation (RNAV) system which was modified to provide the two-segment approach capabilities. Modifications to the basic RNAV software included safety protection logic considered necessary for an operationally acceptable two-segment system. With an aircraft out of revenue service, the system was refined and extensively flight tested, and the profile and procedures were evaluated by representatives of the airlines, airframe manufacturers, the Air Line Pilots Association, and the Federal Aviation Adminstration. The system was determined to be safe and operationally acceptable. It was then placed into scheduled airline service for an evaluation during which 180 approaches were flown by 48 airline pilots. The approach was determined to be compatible with the airline operational environment, although operation of the RNAV system in the existing terminal area air traffic control environment was difficult.

Generic Helicopter-Based Testbed for Surface Terrain Imaging Sensors

NASA Technical Reports Server (NTRS)

Alexander, James; Goldberg, Hannah; Montgomery, James; Spiers, Gary; Liebe, Carl; Johnson, Andrew; Gromov, Konstantin; Konefat, Edward; Lam, Raymond; Meras, Patrick

2008-01-01

To be certain that a candidate sensor system will perform as expected during missions, we have developed a field test system and have executed test flights with a helicopter-mounted sensor platform over desert terrains, which simulate Lunar features. A key advantage to this approach is that different sensors can be tested and characterized in an environment relevant to the flight needs prior to flight. Testing the various sensors required the development of a field test system, including an instrument to validate the truth of the sensor system under test. The field test system was designed to be flexible enough to cover the test needs of many sensors (lidar, radar, cameras) that require an aerial test platform, including helicopters, airplanes, unmanned aerial vehicles (UAV), or balloons. To validate the performance of the sensor under test, the dynamics of the test platform must be known with sufficient accuracy to provide accurate models for input into algorithm development. The test system provides support equipment to measure the dynamics of the field test sensor platform, and allow computation of the truth position, velocity, attitude, and time.

Utility of an airframe referenced spatial auditory display for general aviation operations

NASA Astrophysics Data System (ADS)

Naqvi, M. Hassan; Wigdahl, Alan J.; Ranaudo, Richard J.

2009-05-01

The University of Tennessee Space Institute (UTSI) completed flight testing with an airframe-referenced localized audio cueing display. The purpose was to assess its affect on pilot performance, workload, and situational awareness in two scenarios simulating single-pilot general aviation operations under instrument meteorological conditions. Each scenario consisted of 12 test procedures conducted under simulated instrument meteorological conditions, half with the cue off, and half with the cue on. Simulated aircraft malfunctions were strategically inserted at critical times during each test procedure. Ten pilots participated in the study; half flew a moderate workload scenario consisting of point to point navigation and holding pattern operations and half flew a high workload scenario consisting of non precision approaches and missed approach procedures. Flight data consisted of aircraft and navigation state parameters, NASA Task Load Index (TLX) assessments, and post-flight questionnaires. With localized cues there was slightly better pilot technical performance, a reduction in workload, and a perceived improvement in situational awareness. Results indicate that an airframe-referenced auditory display has utility and pilot acceptance in general aviation operations.

Aeroacoustics of advanced propellers

NASA Technical Reports Server (NTRS)

Groeneweg, John F.

1990-01-01

The aeroacoustics of advanced, high speed propellers (propfans) are reviewed from the perspective of NASA research conducted in support of the Advanced Turboprop Program. Aerodynamic and acoustic components of prediction methods for near and far field noise are summarized for both single and counterrotation propellers in uninstalled and configurations. Experimental results from tests at both takeoff/approach and cruise conditions are reviewed with emphasis on: (1) single and counterrotation model tests in the NASA Lewis 9 by 15 (low speed) and 8 by 6 (high speed) wind tunnels, and (2) full scale flight tests of a 9 ft (2.74 m) diameter single rotation wing mounted tractor and a 11.7 ft (3.57 m) diameter counterrotation aft mounted pusher propeller. Comparisons of model data projected to flight with full scale flight data show good agreement validating the scale model wind tunnel approach. Likewise, comparisons of measured and predicted noise level show excellent agreement for both single and counterrotation propellers. Progress in describing angle of attack and installation effects is also summarized. Finally, the aeroacoustic issues associated with ducted propellers (very high bypass fans) are discussed.

System Engineering Strategy for Distributed Multi-Purpose Simulation Architectures

NASA Technical Reports Server (NTRS)

Bhula, Dlilpkumar; Kurt, Cindy Marie; Luty, Roger

2007-01-01

This paper describes the system engineering approach used to develop distributed multi-purpose simulations. The multi-purpose simulation architecture focuses on user needs, operations, flexibility, cost and maintenance. This approach was used to develop an International Space Station (ISS) simulator, which is called the International Space Station Integrated Simulation (ISIS)1. The ISIS runs unmodified ISS flight software, system models, and the astronaut command and control interface in an open system design that allows for rapid integration of multiple ISS models. The initial intent of ISIS was to provide a distributed system that allows access to ISS flight software and models for the creation, test, and validation of crew and ground controller procedures. This capability reduces the cost and scheduling issues associated with utilizing standalone simulators in fixed locations, and facilitates discovering unknowns and errors earlier in the development lifecycle. Since its inception, the flexible architecture of the ISIS has allowed its purpose to evolve to include ground operator system and display training, flight software modification testing, and as a realistic test bed for Exploration automation technology research and development.

XV-15 Tiltrotor Low Noise Approach Operations

NASA Technical Reports Server (NTRS)

Conner, David A.; Marcolini, Michael A.; Decker, William A.; Cline, John H.; Edwards, Bryan D.; Nicks, Colby O.; Klein, Peter D.

1999-01-01

Acoustic data have been acquired for the XV-15 tiltrotor aircraft performing approach operations for a variety of different approach profile configurations. This flight test program was conducted jointly by NASA, the U.S. Army, and Bell Helicopter Textron, Inc. (BHTI) in June 1997. The XV-15 was flown over a large area microphone array, which was deployed to directly measure the noise footprint produced during actual approach operations. The XV-15 flew realistic approach profiles that culminated in IGE hover over a landing pad. Aircraft tracking and pilot guidance was provided by a Differential Global Positioning System (DGPS) and a flight director system developed at BHTI. Approach profile designs emphasized noise reduction while maintaining handling qualities sufficient for tiltrotor commercial passenger ride comfort and flight safety under Instrument Flight Rules (IFR) conditions. A discussion of the approach profile design philosophy is provided. Five different approach profiles are discussed in detail -- 3 deg., 6 deg., and 9 deg. approaches, and two very different 3 deg. to 9 deg. segmented approaches. The approach profile characteristics are discussed in detail, followed by the noise footprints and handling qualities. Sound exposure levels are also presented on an averaged basis and as a function of the sideline distance for a number of up-range distances from the landing point. A comparison of the noise contour areas is also provided. The results document the variation in tiltrotor noise due to changes in operating condition, and indicate the potential for significant noise reduction using the unique tiltrotor capability of nacelle tilt.

Trajectory Approaches for Launching Hypersonic Flight Tests (Preprint)

DTIC Science & Technology

2014-08-01

This paper presents some approaches toward designing trajectories for hypersonic testing at up to Mach 10 speed using a reusable rocket -powered first...Program to Optimize Simulated Trajectories (POST) code to look at different ways of flying to Mach 10 with a reusable first stage rocket . These trajectories...are good starting points for how to setup a trajectory simulation to meet hypersonic testing needs. 15. SUBJECT TERMS responsive and reusable rocket

A flight test method for pilot/aircraft analysis

NASA Technical Reports Server (NTRS)

Koehler, R.; Buchacker, E.

1986-01-01

In high precision flight maneuvres a pilot is a part of a closed loop pilot/aircraft system. The assessment of the flying qualities is highly dependent on the closed loop characteristics related to precision maneuvres like approach, landing, air-to-air tracking, air-to-ground tracking, close formation flying and air-to air refueling of the receiver. The object of a research program at DFVLR is the final flight phase of an air to ground mission. In this flight phase the pilot has to align the aircraft with the target, correct small deviations from the target direction and keep the target in his sights for a specific time period. To investigate the dynamic behavior of the pilot-aircraft system a special ground attack flight test technique with a prolonged tracking maneuvres was developed. By changing the targets during the attack the pilot is forced to react continously on aiming errors in his sights. Thus the closed loop pilot/aircraft system is excited over a wide frequency range of interest, the pilot gets more information about mission oriented aircraft dynamics and suitable flight test data for a pilot/aircraft analysis can be generated.

Evaluation philosophy for shuttle launched payloads

NASA Technical Reports Server (NTRS)

Heuser, R. E.

1975-01-01

Potential benefits of factory-to-pad testing constitute major cost savings and increase test effectiveness. Overall flight performance will be improved. The factory-to-pad approach is compatible with space shuttle processing and the large space telescope program.

EM-0115-02

NASA Image and Video Library

2013-05-22

During a visit to NASA's Dryden Flight Research Center on May 22, 2013, NASA Administrator Charlie Bolden spoke at a media event showcasing Sierra Nevada Corporation’s (SNC) Dream Chaser flight test vehicle that had recently arrived at the center. Bolden, a former Marine Corps pilot and space shuttle astronaut, also flew a simulation of the Dream Chaser's approach and landing profile at Dryden.

Overturning conclusions of Lévy flight movement patterns by fishing boats and foraging animals.

PubMed

Edwards, Andrew M

2011-06-01

A surprisingly diverse variety of foragers have previously been concluded to exhibit movement patterns known as Lévy flights, a special type of random walk. These foragers range in size from microzooplankton in experiments to fishermen in the Pacific Ocean and the North Sea. The Lévy flight conclusion implies that all the foragers have similar scale-free movement patterns that can be described by a single dimensionless parameter, the exponent micro of a power-law (Pareto) distribution. However, the previous conclusions have been made using methods that have since been shown to be problematic: inaccurate techniques were used to estimate micro, and the power-law distribution was usually assumed to hold without testing any alternative hypotheses. Therefore, I address the open question of whether the previous data still support the Lévy flight hypothesis, and thus determine whether Lévy flights really are so ubiquitous in ecology. I present a comprehensive reanalysis of 17 data sets from seven previous studies for which Lévy flight behavior had been concluded, covering marine, terrestrial, and experimental systems from four continents. I use the modern likelihood and Akaike weights approach to test whether simple alternative models are more supported by the data than Lévy flights. The previously estimated values of the power-law exponent micro do not match those calculated here using the accurate likelihood approach, and almost all of them lie outside of the likelihood-based 95% confidence intervals. Furthermore, the original power-law Lévy flight model is overwhelmingly rejected for 16 out of the 17 data sets when tested against three other simple models. For one data set, the data are consistent with coming from a bounded power-law distribution (a truncated Lévy flight). For three other data sets, an exponential distribution corresponding to a simple Poisson process is suitable. Thus, Lévy flight movement patterns are not the common phenomena that was once thought, and are not suitable for use as ecosystem indicators for fisheries management, as has been proposed.

Advances in Experiment Design for High Performance Aircraft

NASA Technical Reports Server (NTRS)

Morelli, Engene A.

1998-01-01

A general overview and summary of recent advances in experiment design for high performance aircraft is presented, along with results from flight tests. General theoretical background is included, with some discussion of various approaches to maneuver design. Flight test examples from the F-18 High Alpha Research Vehicle (HARV) are used to illustrate applications of the theory. Input forms are compared using Cramer-Rao bounds for the standard errors of estimated model parameters. Directions for future research in experiment design for high performance aircraft are identified.

Antimisting kerosene JT3 engine fuel system integration study

NASA Technical Reports Server (NTRS)

Fiorentino, A.

1987-01-01

An analytical study and laboratory tests were conducted to assist NASA in determining the safety and mission suitability of the modified fuel system and flight tests for the Full-Scale Transport Controlled Impact Demonstration (CID) program. This twelve-month study reviewed and analyzed both the use of antimisting kerosene (AMK) fuel and the incorporation of a fuel degrader on the operational and performance characteristics of the engines tested. Potential deficiencies and/or failures were identified and approaches to accommodate these deficiencies were recommended to NASA Ames -Dryden Flight Research Facility. The result of flow characterization tests on degraded AMK fuel samples indicated levels of degradation satisfactory for the planned missions of the B-720 aircraft. The operability and performance with the AMK in a ground test engine and in the aircraft engines during the test flights were comparable to those with unmodified Jet A. For the final CID test, the JT-3C-7 engines performed satisfactorily while operating on AMK right up to impact.

SHARP Demonstration Flight: Video Broadcast System for Research in Intelligent Flight Characterization and Control

NASA Technical Reports Server (NTRS)

Kitts, Christopher

2001-01-01

The NASA Ames Research Center (Thermal Protection Materials and Systems Branch) is investigating new ceramic materials for the thermal protection of atmospheric entry vehicles. An incremental approach to proving the capabilities of these materials calls for a lifting entry flight test of a sharp leading edge component on the proposed SHARP (Slender Hypervelocity Aerothermodynamic Research Probe) vehicle. This flight test will establish the aerothermal performance constraint under real lifting entry conditions. NASA Ames has been developing the SHARP test flight with SSDL (responsible for the SHARP S I vehicle avionics), Montana State University (responsible for the SHARP S I vehicle airframe), the Wickman Spacecraft and Propulsion Company (responsible for the sounding rocket and launch operations), and with the SCU Intelligent Robotics Program, The SCU team was added well after the rest of the development team had formed. The SCU role was to assist with the development of a real-time video broadcast system which would relay onboard flight video to a communication groundstation. The SCU team would also assist with general vehicle preparation as well as flight operations. At the time of the submission of the original SCU proposal, a test flight in Wyoming was originally targeted for September 2000. This date was moved several times into the Fall of 2000. It was then postponed until the Spring of 2001, and later pushed into late Summer 2001. To date, the flight has still not taken place. These project delays resulted in SCU requesting several no-cost extensions to the project. Based on the most recent conversations with the project technical lead, Paul Kolodjiez, the current plan is for the overall SHARP team to assemble what exists of the vehicle, to document the system, and to 'mothball' the vehicle in anticipation of future flight and funding opportunities.

Airborne Systems Technology Application to the Windshear Threat

NASA Technical Reports Server (NTRS)

Arbuckle, P. Douglas; Lewis, Michael S.; Hinton, David A.

1996-01-01

The general approach and products of the NASA/FAA Airborne Windshear Program conducted by NASA Langley Research Center are summarized, with references provided for the major technical contributions. During this period, NASA conducted 2 years of flight testing to characterize forward-looking sensor performance. The NASA/FAA Airborne Windshear Program was divided into three main elements: Hazard Characterization, Sensor Technology, and Flight Management Systems. Simulation models developed under the Hazard Characterization element are correlated with flight test data. Flight test results comparing the performance and characteristics of the various Sensor Technologies (microwave radar, lidar, and infrared) are presented. Most of the activities in the Flight Management Systems element were conducted in simulation. Simulation results from a study evaluating windshear crew procedures and displays for forward-looking sensor-equipped airplanes are discussed. NASA Langley researchers participated heavily in the FAA process of generating certification guidelines for predictive windshear detection systems. NASA participants felt that more valuable technology products were generated by the program because of this interaction. NASA involvement in the process and the resulting impact on products and technology transfer are discussed in this paper.

Navigation errors encountered using weather-mapping radar for helicopter IFR guidance to oil rigs

NASA Technical Reports Server (NTRS)

Phillips, J. D.; Bull, J. S.; Hegarty, D. M.; Dugan, D. C.

1980-01-01

In 1978 a joint NASA-FAA helicopter flight test was conducted to examine the use of weather-mapping radar for IFR guidance during landing approaches to oil rig helipads. The following navigation errors were measured: total system error, radar-range error, radar-bearing error, and flight technical error. Three problem areas were identified: (1) operational problems leading to pilot blunders, (2) poor navigation to the downwind final approach point, and (3) pure homing on final approach. Analysis of these problem areas suggests improvement in the radar equipment, approach procedure, and pilot training, and gives valuable insight into the development of future navigation aids to serve the off-shore oil industry.

[Peculiarities of research of flying thinking].

PubMed

Kovalenko, P A; Chulaevskiĭ, A O

2011-01-01

New approach to the research of flying thinking is offered. This approach is based on principals of stage-by-stage approach (research of the reflection of every parameter of flight, than its aggregate in figured and conceptual framework), on the usage of the methods of registration of inner and external characteristics of activity of the air staff with the priority of research of content area and mechanisms of flying thinking, typology of content area and mechanisms of flying thinking. This approach is also based on the effectiveness of reflection by means of correlation of the detected figured and conceptual framework with time and correctness of decisions of test flight tasks and with different psychophysiological characteristics.

Decline in Aerobic Fitness After Long-Term Stays on the International Space Station

NASA Technical Reports Server (NTRS)

Lynn, Peggy A.; Minard, Charles; Moore, Alan; Babiak-Vazquez, Adriana

2010-01-01

U.S. and non-Russian International Partner astronauts who participate in long-term International Space Station (ISS) expeditions perform submaximal cycle exercise tests before, during, and after space flight. The heart rate (HR) and oxygen uptake (VO2) responses to exercise are used to estimate peak VO2 (EVO2pk). Purpose: To determine if the following factors are associated with the preflight-to-post flight change in EVO2pk: gender, age, body weight (BW), number of aerobic exercise sessions/wk- during flight, length of flight, EVO2pk measured before and late during the flight, ISS Expedition number and time between landing and the first post flight test. Methods: Records of 37 ISS astronauts (30 male, BW=81.6 plus or minus 8.6 kg; 7 female BW=66.1 plus or minus 4.9 kg [mean plus or minus SD]), age 46 plus or minus 4 years, were retrospectively examined. Peak HR and VO2 were measured approximately 9 months before flight to establish the test protocol. The submaximal cycle test consisted of three 5-minute stages designed to elicit 25, 50, and 75% of VO2pk. EVO2pk was calculated using linear least-squares extrapolation of average HR and VO2 during the last minute of each stage to predict VO2 at maximal HR. VO2 was not measured during flight and was assumed to not be different from preflight. Testing was performed 45 days before launch, late during flight, and during the week after landing. A random-intercept multivariate model was used to determine which characteristics significantly contributed to post flight EVO2pk. Results: In-flight aerobic exercise averaged 5.4 plus or minus 1.2 sessions/wk. ISS flight duration averaged 163 plus or minus 39 d. Mean EVO2pk values were 3.41 plus or minus 0.64 L (raised dot) per minute before flight, 3.09 plus or minus 0.57 L (raised dot) per minute late in flight, and 3.02 plus or minus 0.65 L (raised dot) per minute after flight. Late- and after-flight values were lower (p less than 0.05) than preflight values and did not differ from each other. Time between landing and post flight testing was 4.5 plus or minus 1.6 days. The only factor significantly associated with the post flight EVO2pk value was the late-flight EVO2pk score. Conclusion: Testing performed late during a mission provides a prediction of EVO2pk after landing. This approach may be implemented during longer missions.

Modeling human response errors in synthetic flight simulator domain

NASA Technical Reports Server (NTRS)

Ntuen, Celestine A.

1992-01-01

This paper presents a control theoretic approach to modeling human response errors (HRE) in the flight simulation domain. The human pilot is modeled as a supervisor of a highly automated system. The synthesis uses the theory of optimal control pilot modeling for integrating the pilot's observation error and the error due to the simulation model (experimental error). Methods for solving the HRE problem are suggested. Experimental verification of the models will be tested in a flight quality handling simulation.

Development of the Lens Antenna Deployment Demonstration (LADD) shuttle-attached flight experiment

NASA Technical Reports Server (NTRS)

Hill, H.; Johnston, D.; Frauenberger, H.

1986-01-01

The primary objective of the LADD Program is to develop a technology demonstration test article that can be used for both ground and flight tests to demonstrate the structural and mechanical feasibility and reliability of the single-axis roll-out space based radar (SBR) approach. As designed, the LADD will essentially be a generic strucutural experiment which incorporates all critical technology elements of the operational satellite and is applicable to a number of future antenna systems. However, to fully determine its design integrity for meeting the lens flatness and constant geometry requirements in a zero g environment under extreme thermal conditions, the LADD must be space flight tested. By accurately surveying the structure under varying conditions the membrane tolerance-holding capabilities of the structure will be demonstrated. The flight test will provide data to verify analytical tools used to predict thermal and structural behavior. Most important, the experiment will provide an initial indication of structural damping in a zero g vacuum environment. The recently completed Solar Array Flight Experiment (SAFE) showed orbital damping greater than that experienced during ground testing. From the experience and the information obtained from LADD it is hoped that designs can be confidently extrapolated to operational satellites with apertures in the 20 m by 60 m size range.

General Aviation Interior Noise. Part 2; In-Flight Source/Verification

NASA Technical Reports Server (NTRS)

Unruh, James F.; Till, Paul D.; Palumbo, Daniel L. (Technical Monitor)

2002-01-01

The technical approach made use of the Cessna Model 182E aircraft used in the previous effort as a test bed for noise control application. The present phase of the project reports on flight test results during application of various passive noise treatments in an attempt to verify the noise sources and paths for the aircraft. The data presented establishes the level of interior noise control that can be expected for various passive noise control applications within the aircraft cabin. Subsequent testing will address specific testing to demonstrate the technology available to meet a specified level of noise control by application of passive and/or active noise control technology.

Control integration concept for hypersonic cruise-turn maneuvers

NASA Technical Reports Server (NTRS)

Raney, David L.; Lallman, Frederick J.

1992-01-01

Piloting difficulties associated with conducting aircraft maneuvers in hypersonic flight are caused in part by the nonintuitive nature of the aircraft response and the stringent constraints anticipated on allowable angle of attack and dynamic pressure variations. An approach is documented that provides precise, coordinated maneuver control during excursions from a hypersonic cruise flight path and the necessary flight condition constraints. The approach is to achieve specified guidance commands by resolving altitude and cross range errors into a load factor and bank angle command by using a coordinate transformation that acts as an interface between outer and inner loop flight controls. This interface, referred to as a 'resolver', applies constraints on angle of attack and dynamic pressure perturbations while prioritizing altitude regulation over cross range. An unpiloted test simulation, in which the resolver was used to drive inner loop flight controls, produced time histories of responses to guidance commands and atmospheric disturbances at Mach numbers of 6, 10, 15, and 20. Angle of attack and throttle perturbation constraints, combined with high speed flight effects and the desire to maintain constant dynamic pressure, significantly impact the maneuver envelope for a hypersonic vehicle.

Autonomous rendezvous and capture development infrastructure

NASA Technical Reports Server (NTRS)

Bryan, Thomas C.; Roe, Fred; Coker, Cindy; Nelson, Pam; Johnson, B.

1991-01-01

In the development of the technology for autonomous rendezvous and docking, key infrastructure capabilities must be used for effective and economical development. This involves facility capabilities, both equipment and personnel, to devise, develop, qualify, and integrate ARD elements and subsystems into flight programs. One effective way of reducing technical risks in developing ARD technology is the use of the ultimate test facility, using a Shuttle-based reusable free-flying testbed to perform a Technology Demonstration Test Flight which can be structured to include a variety of additional sensors, control schemes, and operational approaches. This conceptual testbed and flight demonstration will be used to illustrate how technologies and facilities at MSFC can be used to develop and prove an ARD system.

ATD-1 Avionics Phase 2: Post-Flight Data Analysis Report

NASA Technical Reports Server (NTRS)

Scharl, Julien

2017-01-01

This report aims to satisfy Air Traffic Management Technology Demonstration - 1 (ATD-1) Statement of Work (SOW) 3.6.19 and serves as the delivery mechanism for the analysis described in Annex C of the Flight Test Plan. The report describes the data collected and derived as well as the analysis methodology and associated results extracted from the data set collected during the ATD-1 Flight Test. All analyses described in the SOW were performed and are covered in this report except for the analysis of Final Approach Speed and its effect on performance. This analysis was de-prioritized and, at the time of this report, is not considered feasible in the schedule and costs remaining.

Real-time flutter analysis

NASA Technical Reports Server (NTRS)

Walker, R.; Gupta, N.

1984-01-01

The important algorithm issues necessary to achieve a real time flutter monitoring system; namely, the guidelines for choosing appropriate model forms, reduction of the parameter convergence transient, handling multiple modes, the effect of over parameterization, and estimate accuracy predictions, both online and for experiment design are addressed. An approach for efficiently computing continuous-time flutter parameter Cramer-Rao estimate error bounds were developed. This enables a convincing comparison of theoretical and simulation results, as well as offline studies in preparation for a flight test. Theoretical predictions, simulation and flight test results from the NASA Drones for Aerodynamic and Structural Test (DAST) Program are compared.

Noise Prediction of NASA SR2 Propeller in Transonic Conditions

NASA Astrophysics Data System (ADS)

Gennaro, Michele De; Caridi, Domenico; Nicola, Carlo De

2010-09-01

In this paper we propose a numerical approach for noise prediction of high-speed propellers for Turboprop applications. It is based on a RANS approach for aerodynamic simulation coupled with Ffowcs Williams-Hawkings (FW-H) Acoustic Analogy for propeller noise prediction. The test-case geometry adopted for this study is the 8-bladed NASA SR2 transonic cruise propeller, and simulated Sound Pressure Levels (SPL) have been compared with experimental data available from Wind Tunnel and Flight Tests for different microphone locations in a range of Mach numbers between 0.78 and 0.85 and rotational velocities between 7000 and 9000 rpm. Results show the ability of this approach to predict noise to within a few dB of experimental data. Moreover corrections are provided to be applied to acoustic numerical results in order for them to be compared with Wind Tunnel and Flight Test experimental data, as well computational grid requirements and guidelines in order to perform complete aerodynamic and aeroacoustic calculations with highly competitive computational cost.

Structural and Optical Properties Studies Of Ar2+ Ion Implanted Mn Deposited GaAs

NASA Astrophysics Data System (ADS)

De Gennaro, Michele; Caridi, Domenico; de Nicola, Carlo

2010-09-01

In this paper we propose a numerical approach for noise prediction of high-speed propellers for Turboprop applications. It is based on a RANS approach for aerodynamic simulation coupled with Ffowcs Williams-Hawkings (FW-H) Acoustic Analogy for propeller noise prediction. The test-case geometry adopted for this study is the 8-bladed NASA SR2 transonic cruise propeller, and simulated Sound Pressure Levels (SPL) have been compared with experimental data available from Wind Tunnel and Flight Tests for different microphone locations in a range of Mach numbers between 0.78 and 0.85 and rotational velocities between 7000 and 9000 rpm. Results show the ability of this approach to predict noise to within a few dB of experimental data. Moreover corrections are provided to be applied to acoustic numerical results in order for them to be compared with Wind Tunnel and Flight Test experimental data, as well computational grid requirements and guidelines in order to perform complete aerodynamic and aeroacoustic calculations with highly competitive computational cost.

Flying qualities design criteria applicable to supersonic cruise aircraft

NASA Technical Reports Server (NTRS)

Chalk, C. R.

1980-01-01

A comprehensive set of flying qualities design criteria was prepared for use in the supersonic cruise research program. The framework for stating the design criteria is established and design criteria are included which address specific failures, approach to dangerous flight conditions, flight at high angle of attack, longitudinal and lateral directional stability and control, the primary flight control system, and secondary flight controls. Examples are given of lateral directional design criteria limiting lateral accelerations at the cockpit, time to roll through 30 deg of bank, and time delay in the pilot's command path. Flight test data from the Concorde certification program are used to substantiate a number of the proposed design criteria.

Verification and Validation of Adaptive and Intelligent Systems with Flight Test Results

NASA Technical Reports Server (NTRS)

Burken, John J.; Larson, Richard R.

2009-01-01

F-15 IFCS project goals are: a) Demonstrate Control Approaches that can Efficiently Optimize Aircraft Performance in both Normal and Failure Conditions [A] & [B] failures. b) Advance Neural Network-Based Flight Control Technology for New Aerospace Systems Designs with a Pilot in the Loop. Gen II objectives include; a) Implement and Fly a Direct Adaptive Neural Network Based Flight Controller; b) Demonstrate the Ability of the System to Adapt to Simulated System Failures: 1) Suppress Transients Associated with Failure; 2) Re-Establish Sufficient Control and Handling of Vehicle for Safe Recovery. c) Provide Flight Experience for Development of Verification and Validation Processes for Flight Critical Neural Network Software.

KSC-2014-3909

NASA Image and Video Library

2014-09-12

CAPE CANAVERAL, Fla. – Inside the Horizontal Integration Facility at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida, a United Launch Alliance technician on a scissor lift watches as mating of the second stage of a Delta IV Heavy rocket to the core booster of the three booster stages is nearly complete. The rocket will launch the unpiloted Exploration Flight Test-1, or EFT-1. During the mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on the first flight test is planned for December 2014. Photo credit: NASA/Daniel Casper

An in-flight simulator investigation of roll and yaw control power requirements for STOL approach and landing: Development of capability and preliminary results

NASA Technical Reports Server (NTRS)

Ellis, D. R.; Raisinghani, S. C.

1979-01-01

A six-degree-of-freedom variable-response research aircraft was used to determine the minimum lateral-directional control power required for desirable and acceptable levels of handling qualities for the STOL landing approach task in a variety of simulated atmospheric disturbance conditions for a range of lateral-directional response characteristics. Topics covered include the in-flight simulator, crosswind simulation, turbulence simulation, test configurations, and evaluation procedures. Conclusions based on a limited sampling of simulated STOL transport configurations flown to touchdown out of 6 deg, 75 kt MLS approaches, usually with a sidestep maneuver are discussed.

Ares I-X Test Flight Reference Trajectory Development

NASA Technical Reports Server (NTRS)

Starr, Brett R.; Gumbert, Clyde R.; Tartabini, Paul V.

2011-01-01

Ares I-X was the first test flight of NASA's Constellation Program's Ares I crew launch vehicle. Ares I is a two stage to orbit launch vehicle that provides crew access to low Earth orbit for NASA's future manned exploration missions. The Ares I first stage consists of a Shuttle solid rocket motor (SRM) modified to include an additional propellant segment and a liquid propellant upper stage with an Apollo J2X engine modified to increase its thrust capability. The modified propulsion systems were not available for the first test flight, thus the test had to be conducted with an existing Shuttle 4 segment reusable solid rocket motor (RSRM) and an inert Upper Stage. The test flight's primary objective was to demonstrate controllability of an Ares I vehicle during first stage boost and the ability to perform a successful separation. In order to demonstrate controllability, the Ares I-X ascent control algorithms had to maintain stable flight throughout a flight environment equivalent to Ares I. The goal of the test flight reference trajectory development was to design a boost trajectory using the existing RSRM that results in a flight environment equivalent to Ares I. A trajectory similarity metric was defined as the integrated difference between the Ares I and Ares I-X Mach versus dynamic pressure relationships. Optimization analyses were performed that minimized the metric by adjusting the inert upper stage weight and the ascent steering profile. The sensitivity of the optimal upper stage weight and steering profile to launch month was also investigated. A response surface approach was used to verify the optimization results. The analyses successfully defined monthly ascent trajectories that matched the Ares I reference trajectory dynamic pressure versus Mach number relationship to within 10% through Mach 3.5. The upper stage weight required to achieve the match was found to be feasible and varied less than 5% throughout the year. The paper will discuss the flight test requirements, provide Ares I-X vehicle background, discuss the optimization analyses used to meet the requirements, present analysis results, and compare the reference trajectory to the reconstructed flight trajectory.

Development of a Ground Test Concept Based on Multi-Rotors for In-Flight RVD Experimentation

DTIC Science & Technology

2015-08-01

approach was tried by [2, 23]. The drawback of this second approach is that to perform the flight experiments to acquire identification data, the...the idea is to use the rules of compound pendulum [27] for evaluating the moments of inertia of the body. It is also a prototypical system for...Lagrangian dynamics L = K − V where K is the kinetic energy and V is the potential energy of the pendulum . We assume that the total energy at the zero

When the Wheels Touch Earth and the Flight is Through, Pilots Find One Eye is Better Than Two?

NASA Technical Reports Server (NTRS)

Valimont, Brian; Wise, John A.; Nichols, Troy; Best, Carl; Suddreth, John; Cupero, Frank

2009-01-01

This study investigated the impact of near to eye displays on both operational and visual performance by employing a human-in-the-loop simulation of straight-in ILS approaches while using a near to eye (NTE) display. The approaches were flown in simulated visual and instrument conditions while using either a biocular NTE or a monocular NTE display on either the dominant or non dominant eye. The pilot s flight performance, visual acuity, and ability to detect unsafe conditions on the runway were tested.

NACA Photographer North American F-100A (NACA-200) Super Sabre Airplane take-off. The blowing-tupe

NASA Technical Reports Server (NTRS)

1957-01-01

NACA Photographer North American F-100A (NACA-200) Super Sabre Airplane take-off. The blowing-tupe boundary-layer control on the leading- and trailing-edge provided large reductions in takeoff and landing approach speeds. Approach speeds were reduced by about 10 knots (Mar 1960). Note: Used in publication in Flight Research at Ames; 57 Years of Development and Validation of Aeronautical Technology NASA SP-1998-3300 fig. 102 and and Memoirs of a Flight Test Engneer NASA SP-2002-4525

Recent NASA Research on Aerodynamic Modeling of Post-Stall and Spin Dynamics of Large Transport Airplanes

NASA Technical Reports Server (NTRS)

Murch, Austin M.; Foster, John V.

2007-01-01

A simulation study was conducted to investigate aerodynamic modeling methods for prediction of post-stall flight dynamics of large transport airplanes. The research approach involved integrating dynamic wind tunnel data from rotary balance and forced oscillation testing with static wind tunnel data to predict aerodynamic forces and moments during highly dynamic departure and spin motions. Several state-of-the-art aerodynamic modeling methods were evaluated and predicted flight dynamics using these various approaches were compared. Results showed the different modeling methods had varying effects on the predicted flight dynamics and the differences were most significant during uncoordinated maneuvers. Preliminary wind tunnel validation data indicated the potential of the various methods for predicting steady spin motions.

The JT9D Jet Engine Diagnostics Program

NASA Technical Reports Server (NTRS)

Olsson, W. J.

1982-01-01

The various engine deterioration phenomena that affect JT9D performance retention were studied, and approaches to improve performance retention of engines were identified. The program included surveys of historical data, monitoring of in service engines, ground and flight testing of instrumented engines, analysis, and analytical modeling. Performance deterioration is made up of both short and long term modes, both of which are flight cycle related phenomena. Short term deterioration occurs primarily during airplane acceptance testing prior to delivery to the airline. This effect is caused by flight load and power induced clearance closures and engine deflections with resulting rubbing of airfoils and seals. Long term deterioration is caused by erosion of airfoils and gas path seals during ground operation and take off and by cyclic induced thermal distortion of the high pressure turbine airfoils. Studies of possible remedial approaches have shown that performance retention within 1 to 2 percent of initial revenue service performance can be achieved with a proper program of hot section and cold section maintenance.

Flight results from a study of aided inertial navigation applied to landing operations

NASA Technical Reports Server (NTRS)

Mcgee, L. A.; Smith, G. L.; Hegarty, D. M.; Carson, T. M.; Merrick, R. B.; Schmidt, S. F.; Conrad, B.

1973-01-01

An evaluation is presented of the approach and landing performance of a Kalman filter aided inertial navigation system using flight data obtained from a series of approaches and landings of the CV-340 aircraft at an instrumented test area. A description of the flight test is given, in which data recorded included: (1) accelerometer signals from the platform of an INS; (2) three ranges from the Ames-Cubic Precision Ranging System; and (3) radar and barometric altimeter signals. The method of system evaluation employed was postflight processing of the recorded data using a Kalman filter which was designed for use on the XDS920 computer onboard the CV-340 aircraft. Results shown include comparisons between the trajectories as estimated by the Kalman filter aided system and as determined from cinetheodolite data. Data start initialization of the Kalman filter, operation at a practical data rate, postflight modeling of sensor errors and operation under the adverse condition of bad data are illustrated.

Practical input optimization for aircraft parameter estimation experiments. Ph.D. Thesis, 1990

NASA Technical Reports Server (NTRS)

Morelli, Eugene A.

1993-01-01

The object of this research was to develop an algorithm for the design of practical, optimal flight test inputs for aircraft parameter estimation experiments. A general, single pass technique was developed which allows global optimization of the flight test input design for parameter estimation using the principles of dynamic programming with the input forms limited to square waves only. Provision was made for practical constraints on the input, including amplitude constraints, control system dynamics, and selected input frequency range exclusions. In addition, the input design was accomplished while imposing output amplitude constraints required by model validity and considerations of safety during the flight test. The algorithm has multiple input design capability, with optional inclusion of a constraint that only one control move at a time, so that a human pilot can implement the inputs. It is shown that the technique can be used to design experiments for estimation of open loop model parameters from closed loop flight test data. The report includes a new formulation of the optimal input design problem, a description of a new approach to the solution, and a summary of the characteristics of the algorithm, followed by three example applications of the new technique which demonstrate the quality and expanded capabilities of the input designs produced by the new technique. In all cases, the new input design approach showed significant improvement over previous input design methods in terms of achievable parameter accuracies.

KSC-2014-3662

NASA Image and Video Library

2014-08-25

CAPE CANAVERAL, Fla. – The umbilical swing arm for Orion's Exploration Flight Test 1, or EFT-1, has been attached to the uppermost location on the fixed umbilical tower at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. All three swing arms on the tower are undergoing tests to confirm that they are operating correctly. The uppermost swing arm will carry umbilicals that will be mated to Orion's launch abort system and environmental control system. During launch, all three umbilicals will pull away from Orion and the United Launch Alliance Delta IV Heavy rocket at T-0. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on its first flight test is planned for fall 2014. Photo credit: NASA/Daniel Casper

KSC-2014-3660

NASA Image and Video Library

2014-08-25

CAPE CANAVERAL, Fla. – The umbilical swing arm for Orion's Exploration Flight Test 1, or EFT-1, has been attached to the uppermost location on the fixed umbilical tower at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. All three swing arms on the tower will undergo tests to confirm that they are operating correctly. The uppermost swing arm will carry umbilicals that will be mated to Orion's launch abort system and environmental control system. During launch, all three umbilicals will pull away from Orion and the United Launch Alliance Delta IV Heavy rocket at T-0. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on its first flight test is planned for fall 2014. Photo credit: NASA/Daniel Casper

KSC-2014-3661

NASA Image and Video Library

2014-08-25

CAPE CANAVERAL, Fla. – The umbilical swing arm for Orion's Exploration Flight Test 1, or EFT-1, has been attached to the uppermost location on the fixed umbilical tower at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. All three swing arms on the tower will undergo tests to confirm that they are operating correctly. The uppermost swing arm will carry umbilicals that will be mated to Orion's launch abort system and environmental control system. During launch, all three umbilicals will pull away from Orion and the United Launch Alliance Delta IV Heavy rocket at T-0. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on its first flight test is planned for fall 2014. Photo credit: NASA/Daniel Casper

Design and Analysis of Modules for Segmented X-Ray Optics

NASA Technical Reports Server (NTRS)

McClelland, Ryan S.; BIskach, Michael P.; Chan, Kai-Wing; Saha, Timo T; Zhang, William W.

2012-01-01

Future X-ray astronomy missions demand thin, light, and closely packed optics which lend themselves to segmentation of the annular mirrors and, in turn, a modular approach to the mirror design. The modular approach to X-ray Flight Mirror Assembly (FMA) design allows excellent scalability of the mirror technology to support a variety of mission sizes and science objectives. This paper describes FMA designs using slumped glass mirror segments for several X-ray astrophysics missions studied by NASA and explores the driving requirements and subsequent verification tests necessary to qualify a slumped glass mirror module for space-flight. A rigorous testing program is outlined allowing Technical Development Modules to reach technical readiness for mission implementation while reducing mission cost and schedule risk.

Report of the Aircraft Systems/Flight Test Workshop (1979) Aircraft Engineering Division, Systems and Flight Test Branches, held October 2 - 10, 1979, NASA/AMES Research Center, Moffett Field, CA

DTIC Science & Technology

1979-10-10

intercept the ILS at Allegheny County. The outside air temperature was +60 at 3000 feet. It was possible to perform the ILS approach within one dot...stMatr wW lrve of the Aru paca roferomd -L Zt* AMU taliax. JAM4 0. E8DLMSM cc: P-13Ol/13iA/1O/203/200/g-21-O/23/C-E’Ifl-4 no 0Ai3 ..c /2 .89 AGENDA ITEM...to intercept the ILS at Allegheny County. The outside air temperature was +60 at 3000 feet. It was possible to perform the ILS approach within one dot

Flight evaluation of the terminal guidance system

NASA Technical Reports Server (NTRS)

Sandlin, D. R.

1981-01-01

The terminal guidance system (TGS) is avionic equipment which gives guidance along a curved descending flight path to a landing. A Cessna 182 was used as the test aircraft and the TGS was installed and connected to the altimeter, DME, RMI, and gyro compass. Approaches were flown by three different pilots. When the aircraft arrives at the termination point, it is set up on final approach for a landing. The TGS provides guidance for curved descending approaches with guideslopes of 6 deg which required, for experienced pilots, workloads that are approximately the same as for an ILS. The glideslope is difficult to track within 1/2 n.m. of the VOR/DME station. The system permits, for experienced pilots, satisfactory approaches with a turn radius as low as 1/2 n.m. and a glideslope of 6 deg. Turn angles have little relation to pilot workload for curved approaches. Pilot experience is a factor for curved approaches. Pilots with low instrument time have difficulty flying steep approaches with small turn radius. Turbulence increases the pilot workload for curved approaches. The TGS does not correct to a given flight path over the ground nor does it adequately compensate for wind drift.

The Use of Information Technology To Enhance Learning in Geological Field Trips.

ERIC Educational Resources Information Center

Hesthammer, Jonny; Fossen, Haakon; Sautter, Michael; Saether, Bjorn; Johansen, Stale Emile

2002-01-01

Reports on the testing of two approaches to enhance learning in geological field trips through the use of technology. One approach used an advanced flight simulator and the other used digital cameras and computers. (Contains 18 references.) (DDR)

Commercial Parts Technology Qualification Processes

NASA Technical Reports Server (NTRS)

Cooper, Mark S.

2013-01-01

Many high-reliability systems, including space systems, use selected commercial parts (including Plastic Encapsulated Microelectronics or PEMs) for unique functionality, small size, low weight, high mechanical shock resistance, and other factors. Predominantly this usage is subjected to certain 100% tests (typically called screens) and certain destructive tests usually (but not always) performed on the flight lot (typically called qualification tests). Frequently used approaches include those documented in EEE-INST-002 and JPL DocID62212 (which are sometimes modified by the particular aerospace space systems manufacturer). In this study, approaches from these documents and several space systems manufacturers are compared to approaches from a launch systems manufacturer (SpaceX), an implantable medical electronics manufacturer (Medtronics), and a high-reliability transport system process (automotive systems). In the conclusions section, these processes are outlined for all of these cases and presented in tabular form. Then some simple comparisons are made. In this introduction section, the PEM technology qualification process is described, as documented in EEE-INST-002 (written by the Goddard Space Flight Center, GSFC), as well as the somewhat modified approach employed at the Jet Propulsion Laboratory (JPL). Approaches used at several major NASA contractors are also described

KSC-2014-3668

NASA Image and Video Library

2014-08-25

CAPE CANAVERAL, Fla. – The umbilical swing arm for Orion's Exploration Flight Test 1, or EFT-1, has been attached to the uppermost location on the fixed umbilical tower at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. The swing arm is undergoing a test to confirm that it is operating correcting. During the test, the arm was swung out and closer to the Vertical Integration Facility at the pad. The uppermost swing arm will carry umbilicals that will be mated to Orion's launch abort system and environmental control system. During launch, all three umbilicals will pull away from Orion and the United Launch Alliance Delta IV Heavy rocket at T-0. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on its first flight test is planned for fall 2014. Photo credit: NASA/Daniel Casper

Input design for identification of aircraft stability and control derivatives

NASA Technical Reports Server (NTRS)

Gupta, N. K.; Hall, W. E., Jr.

1975-01-01

An approach for designing inputs to identify stability and control derivatives from flight test data is presented. This approach is based on finding inputs which provide the maximum possible accuracy of derivative estimates. Two techniques of input specification are implemented for this objective - a time domain technique and a frequency domain technique. The time domain technique gives the control input time history and can be used for any allowable duration of test maneuver, including those where data lengths can only be of short duration. The frequency domain technique specifies the input frequency spectrum, and is best applied for tests where extended data lengths, much longer than the time constants of the modes of interest, are possible. These technqiues are used to design inputs to identify parameters in longitudinal and lateral linear models of conventional aircraft. The constraints of aircraft response limits, such as on structural loads, are realized indirectly through a total energy constraint on the input. Tests with simulated data and theoretical predictions show that the new approaches give input signals which can provide more accurate parameter estimates than can conventional inputs of the same total energy. Results obtained indicate that the approach has been brought to the point where it should be used on flight tests for further evaluation.

Man-vehicle systems research facility advanced aircraft flight simulator throttle mechanism

NASA Technical Reports Server (NTRS)

Kurasaki, S. S.; Vallotton, W. C.

1985-01-01

The Advanced Aircraft Flight Simulator is equipped with a motorized mechanism that simulates a two engine throttle control system that can be operated via a computer driven performance management system or manually by the pilots. The throttle control system incorporates features to simulate normal engine operations and thrust reverse and vary the force feel to meet a variety of research needs. While additional testing to integrate the work required is principally now in software design, since the mechanical aspects function correctly. The mechanism is an important part of the flight control system and provides the capability to conduct human factors research of flight crews with advanced aircraft systems under various flight conditions such as go arounds, coupled instrument flight rule approaches, normal and ground operations and emergencies that would or would not normally be experienced in actual flight.

Investigating the benefits of scene linking for a pathway HMD: from laboratory flight experiments to flight tests

NASA Astrophysics Data System (ADS)

Schmerwitz, Sven; Többen, Helmut; Lorenz, Bernd; Iijima, Tomoko; Kuritz-Kaiser, Anthea

2006-05-01

Pathway-in-the-sky displays enable pilots to accurately fly difficult trajectories. However, these displays may drive pilots' attention to the aircraft guidance task at the expense of other tasks particularly when the pathway display is located head-down. A pathway HUD may be a viable solution to overcome this disadvantage. Moreover, the pathway may mitigate the perceptual segregation between the static near domain and the dynamic far domain and hence, may improve attention switching between both sources. In order to more comprehensively overcome the perceptual near-to-far domain disconnect alphanumeric symbols could be attached to the pathway leading to a HUD design concept called 'scene-linking'. Two studies are presented that investigated this concept. The first study used a simplified laboratory flight experiment. Pilots (N=14) flew a curved trajectory through mountainous terrain and had to detect display events (discrete changes in a command speed indicator to be matched with current speed) and outside scene events (hostile SAM station on ground). The speed indicators were presented in superposition to the scenery either in fixed position or scene-linked to the pathway. Outside scene event detection was found improved with scene linking, however, flight-path tracking was markedly deteriorated. In the second study a scene-linked pathway concept was implemented on a monocular retinal scanning HMD and tested in real flights on a Do228 involving 5 test pilots. The flight test mainly focused at usability issues of the display in combination with an optical head tracker. Visual and instrument departure and approach tasks were evaluated comparing HMD navigation with standard instrument or terrestrial navigation. The study revealed limitations of the HMD regarding its see-through capability, field of view, weight and wearing comfort that showed to have a strong influence on pilot acceptance rather than rebutting the approach of the display concept as such.

Project Morpheus: Lessons Learned in Lander Technology Development

NASA Technical Reports Server (NTRS)

Olansen, Jon B.; Munday, Stephen R.; Mitchell, Jennifer D.

2013-01-01

NASA's Morpheus Project has developed and tested a prototype planetary lander capable of vertical takeoff and landing, that is designed to serve as a testbed for advanced spacecraft technologies. The lander vehicle, propelled by a LOX/Methane engine and sized to carry a 500kg payload to the lunar surface, provides a platform for bringing technologies from the laboratory into an integrated flight system at relatively low cost. Designed, developed, manufactured and operated in-house by engineers at Johnson Space Center, the initial flight test campaign began on-site at JSC less than one year after project start. After two years of testing, including two major upgrade periods, and recovery from a test crash that caused the loss of a vehicle, flight testing will evolve to executing autonomous flights simulating a 500m lunar approach trajectory, hazard avoidance maneuvers, and precision landing, incorporating the Autonomous Landing and Hazard Avoidance (ALHAT) sensor suite. These free-flights are conducted at a simulated planetary landscape built at Kennedy Space Center's Shuttle Landing Facility. The Morpheus Project represents a departure from recent NASA programs and projects that traditionally require longer development lifecycles and testing at remote, dedicated testing facilities. This paper expands on the project perspective that technologies offer promise, but capabilities offer solutions. It documents the integrated testing campaign, the infrastructure and testing facilities, and the technologies being evaluated in this testbed. The paper also describes the fast pace of the project, rapid prototyping, frequent testing, and lessons learned during this departure from the traditional engineering development process at NASA's Johnson Space Center.

Equivalence Testing as a Tool for Fatigue Risk Management in Aviation.

PubMed

Wu, Lora J; Gander, Philippa H; van den Berg, Margo; Signal, T Leigh

2018-04-01

Many civilian aviation regulators favor evidence-based strategies that go beyond hours-of-service approaches for managing fatigue risk. Several countries now allow operations to be flown outside of flight and duty hour limitations, provided airlines demonstrate an alternative method of compliance that yields safety levels "at least equivalent to" the prescriptive regulations. Here we discuss equivalence testing in occupational fatigue risk management. We present suggested ratios/margins of practical equivalence when comparing operations inside and outside of prescriptive regulations for two common aviation safety performance indicators: total in-flight sleep duration and psychomotor vigilance task reaction speed. Suggested levels of practical equivalence, based on expertise coupled with evidence from field and laboratory studies, are ≤ 30 min in-flight sleep and ± 15% of reference response speed. Equivalence testing is illustrated in analyses of a within-subjects field study during an out-and-back long-range trip. During both sectors of their trip, 41 pilots were monitored via actigraphy, sleep diary, and top of descent psychomotor vigilance task. Pilots were assigned to take rest breaks in a standard lie-flat bunk on one sector and in a bunk tapered 9 from hip to foot on the other sector. Total in-flight sleep duration (134 ± 53 vs. 135 ± 55 min) and mean reaction speed at top of descent (3.94 ± 0.58 vs. 3.77 ± 0.58) were equivalent after rest in the full vs. tapered bunk. Equivalence testing is a complimentary statistical approach to difference testing when comparing levels of fatigue and performance in occupational settings and can be applied in transportation policy decision making.Wu LJ, Gander PH, van den Berg M, Signal TL. Equivalence testing as a tool for fatigue risk management in aviation. Aerosp Med Hum Perform. 2018; 89(4):383-388.

Full-envelope aerodynamic modeling of the Harrier aircraft

NASA Technical Reports Server (NTRS)

Mcnally, B. David

1986-01-01

A project to identify a full-envelope model of the YAV-8B Harrier using flight-test and parameter identification techniques is described. As part of the research in advanced control and display concepts for V/STOL aircraft, a full-envelope aerodynamic model of the Harrier is identified, using mathematical model structures and parameter identification methods. A global-polynomial model structure is also used as a basis for the identification of the YAV-8B aerodynamic model. State estimation methods are used to ensure flight data consistency prior to parameter identification.Equation-error methods are used to identify model parameters. A fixed-base simulator is used extensively to develop flight test procedures and to validate parameter identification software. Using simple flight maneuvers, a simulated data set was created covering the YAV-8B flight envelope from about 0.3 to 0.7 Mach and about -5 to 15 deg angle of attack. A singular value decomposition implementation of the equation-error approach produced good parameter estimates based on this simulated data set.

Reverse Engineering Crosswind Limits - A New Flight Test Technique?

NASA Technical Reports Server (NTRS)

Asher, Troy A.; Willliams, Timothy L.; Strovers, Brian K.

2013-01-01

During modification of a Gulfstream III test bed aircraft for an experimental flap project, all roll spoiler hardware had to be removed to accommodate the test article. In addition to evaluating the effects on performance and flying qualities resulting from the modification, the test team had to determine crosswind limits for an airplane previously certified with roll spoilers. Predictions for the modified aircraft indicated the maximum amount of steady state sideslip available during the approach and landing phase would be limited by aileron authority rather than by rudder. Operating out of a location that tends to be very windy, an arbitrary and conservative wind limit would have either been overly restrictive or potentially unsafe if chosen poorly. When determining a crosswind limit, how much reserve roll authority was necessary? Would the aircraft, as configured, have suitable handling qualities for long-term use as a flying test bed? To answer these questions, the test team combined two typical flight test techniques into a new maneuver called the sideslip-to-bank maneuver, and was able to gather flying qualities data, evaluate aircraft response and measure trends for various crosswind scenarios. This paper will describe the research conducted, the maneuver, flight conditions, predictions, and results from this in-flight evaluation of crosswind capability.

Helicopter precision approach capability using the Global Positioning System

NASA Technical Reports Server (NTRS)

Kaufmann, David N.

1992-01-01

The period between 1 July and 31 December, 1992, was spent developing a research plan as well as a navigation system document and flight test plan to investigate helicopter precision approach capability using the Global Positioning System (GPS). In addition, all hardware and software required for the research was acquired, developed, installed, and verified on both the test aircraft and the ground-based reference station.

Tiltrotor Acoustic Flight Test: Terminal Area Operations

NASA Technical Reports Server (NTRS)

SantaMaria, O. L.; Wellman, J. B.; Conner, D. A.; Rutledge, C. K.

1991-01-01

This paper provides a comprehensive description of an acoustic flight test of the XV- 15 Tiltrotor Aircraft with Advanced Technology Blades (ATB) conducted in August and September 1991 at Crows Landing, California. The purpose of this cooperative research effort of the NASA Langley and Ames Research Centers was to obtain a preliminary, high quality database of far-field acoustics for terminal area operations of the XV-15 at a takeoff gross weight of approximately 14,000 lbs for various glide slopes, airspeeds, rotor tip speeds, and nacelle tilt angles. The test also was used to assess the suitability of the Crows Landing complex for full scale far-field acoustic testing. This was the first acoustic flight test of the XV-15 aircraft equipped with ATB involving approach and level flyover operations. The test involved coordination of numerous personnel, facilities and equipment. Considerable effort was made to minimize potential extraneous noise sources unique to the region during the test. Acoustic data from the level flyovers were analyzed, then compared with data from a previous test of the XV-15 equipped with Standard Metal Blades

A Vision-Based Relative Navigation Approach for Autonomous Multirotor Aircraft

NASA Astrophysics Data System (ADS)

Leishman, Robert C.

Autonomous flight in unstructured, confined, and unknown GPS-denied environments is a challenging problem. Solutions could be tremendously beneficial for scenarios that require information about areas that are difficult to access and that present a great amount of risk. The goal of this research is to develop a new framework that enables improved solutions to this problem and to validate the approach with experiments using a hardware prototype. In Chapter 2 we examine the consequences and practical aspects of using an improved dynamic model for multirotor state estimation, using only IMU measurements. The improved model correctly explains the measurements available from the accelerometers on a multirotor. We provide hardware results demonstrating the improved attitude, velocity and even position estimates that can be achieved through the use of this model. We propose a new architecture to simplify some of the challenges that constrain GPS-denied aerial flight in Chapter 3. At the core, the approach combines visual graph-SLAM with a multiplicative extended Kalman filter (MEKF). More importantly, we depart from the common practice of estimating global states and instead keep the position and yaw states of the MEKF relative to the current node in the map. This relative navigation approach provides a tremendous benefit compared to maintaining estimates with respect to a single global coordinate frame. We discuss the architecture of this new system and provide important details for each component. We verify the approach with goal-directed autonomous flight-test results. The MEKF is the basis of the new relative navigation approach and is detailed in Chapter 4. We derive the relative filter and show how the states must be augmented and marginalized each time a new node is declared. The relative estimation approach is verified using hardware flight test results accompanied by comparisons to motion capture truth. Additionally, flight results with estimates in the control loop are provided. We believe that the relative, vision-based framework described in this work is an important step in furthering the capabilities of indoor aerial navigation in confined, unknown environments. Current approaches incur challenging problems by requiring globally referenced states. Utilizing a relative approach allows more flexibility as the critical, real-time processes of localization and control do not depend on computationally-demanding optimization and loop-closure processes.

The Effect of Instrument Approach Procedure Chart Design on Pilot Search Speed and Response Accuracy - Flight Test Results

DOT National Transportation Integrated Search

1995-06-01

Instrument approach procedure (IAP) charts can be densely packed with information. This high information density can : make information difficult to find, particularly in a poorly lit cockpit during turbulence. The Voipe Center's Cockpit : Hunan Fact...

A-5A on lakebed.

NASA Image and Video Library

1963-03-25

A North American Aviation A-5A Vigilante (Navy serial number 147858/NASA tail number 858) arrived from the Naval Air Test Center, Patuxent River, MD, on December 19, 1962, at the NASA Flight Research Center (now, Dryden Flight Research Center, Edwards, CA). The Center flew the A-5A in a year-long series of flights in support of the U.S. supersonic transport program. The Center flew the aircraft to determine the let-down and approach conditions of a supersonic transport flying into a dense air traffic network. With the completion of the research flights, the Center sent the A-5A back to the Navy on December 20, 1963.

A-5A on lakebed.

NASA Image and Video Library

1963-10-25

A North American Aviation A-5A Vigilante (Navy serial number 147858/NASA tail number 858) arrived from the Naval Air Test Center, Patuxent River, MD, on December 19, 1962, at the NASA Flight Research Center (now, Dryden Flight Research Center, Edwards, CA). The Center flew the A-5A in a year-long series of flights in support of the U.S. supersonic transport program. The Center flew the aircraft to determine the let-down and approach conditions of a supersonic transport flying into a dense air traffic network. With the completion of the research flights, the Center sent the A-5A back to the Navy on December 20, 1963.

Orbiter 'Enterprise' rides 'piggy-back' atop NASA 747 carrier

NASA Technical Reports Server (NTRS)

1977-01-01

The Orbiter 101 'Enterprise' rides 'piggy-back' atop the NASA 747 carrier aircraft during the second free flight of the Shuttle Apporach and Landing Tests (ALTs) conducted on September 13, 1977 at Dryden Flight Research Center in Southern California. One chase plane can be seen in the left background, another appearing to be directly under the Boeing 747. Astronauts Joe H. Engle, and Richard H. Truly were the crew of the 'Enterprise.' The ALT free flights are designed to verify Orbiter subsonic airworthiness, integrated systems operations and pilot-guided approach and landing capability and satisfying prerequisites to automatic flight control and navigation mode.

Approaching birds with drones: first experiments and ethical guidelines.

PubMed

Vas, Elisabeth; Lescroël, Amélie; Duriez, Olivier; Boguszewski, Guillaume; Grémillet, David

2015-02-01

Unmanned aerial vehicles, commonly called drones, are being increasingly used in ecological research, in particular to approach sensitive wildlife in inaccessible areas. Impact studies leading to recommendations for best practices are urgently needed. We tested the impact of drone colour, speed and flight angle on the behavioural responses of mallards Anas platyrhynchos in a semi-captive situation, and of wild flamingos (Phoenicopterus roseus) and common greenshanks (Tringa nebularia) in a wetland area. We performed 204 approach flights with a quadricopter drone, and during 80% of those we could approach unaffected birds to within 4 m. Approach speed, drone colour and repeated flights had no measurable impact on bird behaviour, yet they reacted more to drones approaching vertically. We recommend launching drones farther than 100 m from the birds and adjusting approach distance according to species. Our study is a first step towards a sound use of drones for wildlife research. Further studies should assess the impacts of different drones on other taxa, and monitor physiological indicators of stress in animals exposed to drones according to group sizes and reproductive status. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Testing of Environmental Satellite Bus-Instrument Interfaces Using Engineering Models

NASA Technical Reports Server (NTRS)

Gagnier, Don; Hayner, Rick; Roza, Michael; Nosek, Thomas; Razzaghi, Andrea

2004-01-01

This paper discusses the formulation and execution of a laboratory test of the electrical interfaces between multiple atmospheric science instruments and the spacecraft bus that carries them. The testing, performed in 2002, used engineering models of the instruments that will be flown on the Aura s p a c m and of the Aura spacecraft bus electronics. Aura is one of NASA's Earth Observing System @OS) Program missions managed by the Goddard Space Flight Center. The test was designed to evaluate the complex interfaces in the spacecraft and instrument command and data handling (C&DH) subsystems prior to integration of the complete flight instruments on the spacecraft. A problem discovered during (and not before) the flight hardware integration phase can cause significant cost and schedule impacts. The testing successfully surfaced problems and led to their resolution before the full-up integration phase, saving significant cost and schedule time. This approach could be used on future environmental satellite programs involving multiple, complex scientific instruments being integrated onto a bus.

Exploring Modeling Options and Conversion of Average Response to Appropriate Vibration Envelopes for a Typical Cylindrical Vehicle Panel with Rib-stiffened Design

NASA Technical Reports Server (NTRS)

Harrison, Phil; LaVerde, Bruce; Teague, David

2009-01-01

Although applications for Statistical Energy Analysis (SEA) techniques are more widely used in the aerospace industry today, opportunities to anchor the response predictions using measured data from a flight-like launch vehicle structure are still quite valuable. Response and excitation data from a ground acoustic test at the Marshall Space Flight Center permitted the authors to compare and evaluate several modeling techniques available in the SEA module of the commercial code VA One. This paper provides an example of vibration response estimates developed using different modeling approaches to both approximate and bound the response of a flight-like vehicle panel. Since both vibration response and acoustic levels near the panel were available from the ground test, the evaluation provided an opportunity to learn how well the different modeling options can match band-averaged spectra developed from the test data. Additional work was performed to understand the spatial averaging of the measurements across the panel from measured data. Finally an evaluation/comparison of two conversion approaches from the statistical average response results that are output from an SEA analysis to a more useful envelope of response spectra appropriate to specify design and test vibration levels for a new vehicle.

Three-dimensional landing zone joint capability technology demonstration

NASA Astrophysics Data System (ADS)

Savage, James; Goodrich, Shawn; Ott, Carl; Szoboszlay, Zoltan; Perez, Alfonso; Soukup, Joel; Burns, H. N.

2014-06-01

The Three-Dimensional Landing Zone (3D-LZ) Joint Capability Technology Demonstration (JCTD) is a 27-month program to develop an integrated LADAR and FLIR capability upgrade for USAF Combat Search and Rescue HH-60G Pave Hawk helicopters through a retrofit of current Raytheon AN/AAQ-29 turret systems. The 3D-LZ JCTD builds upon a history of technology programs using high-resolution, imaging LADAR to address rotorcraft cruise, approach to landing, landing, and take-off in degraded visual environments with emphasis on brownout, cable warning and obstacle avoidance, and avoidance of controlled flight into terrain. This paper summarizes ladar development, flight test milestones, and plans for a final flight test demonstration and Military Utility Assessment in 2014.

Sierra Nevada Corporation (SNC) Dream Chaser arrival at Armstron

NASA Image and Video Library

2017-01-25

Sierra Nevada Corporation’s Dream Chaser spacecraft arrives by truck at NASA’s Armstrong Flight Research Center in California, located on Edwards Air Force Base. The spacecraft will undergo several months of testing in preparation for its approach and landing flight on the base’s 22L runway. The test series is part of a developmental space act agreement SNC has with NASA’s Commercial Crew Program and will help SNC validate aerodynamic properties, flight software and control system performance. The Dream Chaser is also being prepared to deliver cargo to the International Space Station under NASA’s Commercial Resupply Services 2 contract beginning in 2019. The cargo Dream Chaser will fly at least six delivery missions to and from the space station by 2024.

Sierra Nevada Corporation (SNC) Dream Chaser arrival at Armstrong

NASA Image and Video Library

2017-01-25

Sierra Nevada Corporation’s Dream Chaser spacecraft arrives by truck at NASA’s Armstrong Flight Research Center in California, located on Edwards Air Force Base. The spacecraft will undergo several months of testing in preparation for its approach and landing flight on the base’s 22L runway. The test series is part of a developmental space act agreement SNC has with NASA’s Commercial Crew Program and will help SNC validate aerodynamic properties, flight software and control system performance. The Dream Chaser is also being prepared to deliver cargo to the International Space Station under NASA’s Commercial Resupply Services 2 contract beginning in 2019. The cargo Dream Chaser will fly at least six delivery missions to and from the space station by 2024.

Autonomous rendezvous and capture development infrastructure

NASA Technical Reports Server (NTRS)

Bryan, Thomas C.

1991-01-01

In the development of the technology for autonomous rendezvous and docking, key infrastructure capabilities must be used for effective and economical development. This need involves facility capabilities, both equipment and personnel, to devise, develop, qualify, and integrate ARD elements and subsystems into flight programs. One effective way of reducing technical risks in developing ARD technology is the use of the Low Earth Orbit test facility. Using a reusable free-flying testbed carried in the Shuttle, as a technology demonstration test flight, can be structured to include a variety of sensors, control schemes, and operational approaches. This testbed and flight demonstration concept will be used to illustrate how technologies and facilities at MSFC can be used to develop and prove an ARD system.

NASA's approach to space commercialization

NASA Technical Reports Server (NTRS)

Gillam, Isaac T., IV

1986-01-01

The NASA Office of Commercial Programs fosters private participation in commercially oriented space projects. Five Centers for the Commercial Development of Space encourage new ideas and perform research which may yield commercial processes and products for space ventures. Joint agreements allow companies who present ideas to NASA and provide flight hardware access to a free launch and return from orbit. The experimenters furnish NASA with sufficient data to demonstrate the significance of the results. Ground-based tests are arranged for smaller companies to test the feasibility of concepts before committing to the costs of developing hardware. Joint studies of mutual interest are performed by NASA and private sector researchers, and two companies have signed agreements for a series of flights in which launch costs are stretched out to meet projected income. Although Shuttle flights went on hold following the Challenger disaster, extensive work continues on the preparation of commercial research payloads that will fly when Shuttle flights resume.

Determining XV-15 aeroelastic modes from flight data with frequency-domain methods

NASA Technical Reports Server (NTRS)

Acree, C. W., Jr.; Tischler, Mark B.

1993-01-01

The XV-15 tilt-rotor wing has six major aeroelastic modes that are close in frequency. To precisely excite individual modes during flight test, dual flaperon exciters with automatic frequency-sweep controls were installed. The resulting structural data were analyzed in the frequency domain (Fourier transformed). All spectral data were computed using chirp z-transforms. Modal frequencies and damping were determined by fitting curves to frequency-response magnitude and phase data. The results given in this report are for the XV-15 with its original metal rotor blades. Also, frequency and damping values are compared with theoretical predictions made using two different programs, CAMRAD and ASAP. The frequency-domain data-analysis method proved to be very reliable and adequate for tracking aeroelastic modes during flight-envelope expansion. This approach required less flight-test time and yielded mode estimations that were more repeatable, compared with the exponential-decay method previously used.

System design from mission definition to flight validation

NASA Technical Reports Server (NTRS)

Batill, S. M.

1992-01-01

Considerations related to the engineering systems design process and an approach taken to introduce undergraduate students to that process are presented. The paper includes details on a particular capstone design course. This course is a team oriented aircraft design project which requires the students to participate in many phases of the system design process, from mission definition to validation of their design through flight testing. To accomplish this in a single course requires special types of flight vehicles. Relatively small-scale, remotely piloted vehicles have provided the class of aircraft considered in this course.

Apollo experience report: Flight anomaly resolution

NASA Technical Reports Server (NTRS)

Lobb, J. D.

1975-01-01

The identification of flight anomalies, the determination of their causes, and the approaches taken for corrective action are described. Interrelationships of the broad range of disciplines involved with the complex systems and the team concept employed to ensure timely and accurate resolution of anomalies are discussed. The documentation techniques and the techniques for management of anomaly resolution are included. Examples of specific anomalies are presented in the original form of their progressive documentation. Flight anomaly resolution functioned as a part of the real-time mission support and postflight testing, and results were included in the postflight documentation.

Bayes Analysis and Reliability Implications of Stress-Rupture Testing a Kevlar/Epoxy COPV Using Temperature and Pressure Acceleration

NASA Technical Reports Server (NTRS)

Phoenix, S. Leigh; Kezirian, Michael T.; Murthy, Pappu L. N.

2009-01-01

Composite Overwrapped Pressure Vessels (COPVs) that have survived a long service time under pressure generally must be recertified before service is extended. Flight certification is dependent on the reliability analysis to quantify the risk of stress rupture failure in existing flight vessels. Full certification of this reliability model would require a statistically significant number of lifetime tests to be performed and is impractical given the cost and limited flight hardware for certification testing purposes. One approach to confirm the reliability model is to perform a stress rupture test on a flight COPV. Currently, testing of such a Kevlar49 (Dupont)/epoxy COPV is nearing completion. The present paper focuses on a Bayesian statistical approach to analyze the possible failure time results of this test and to assess the implications in choosing between possible model parameter values that in the past have had significant uncertainty. The key uncertain parameters in this case are the actual fiber stress ratio at operating pressure, and the Weibull shape parameter for lifetime; the former has been uncertain due to ambiguities in interpreting the original and a duplicate burst test. The latter has been uncertain due to major differences between COPVs in the database and the actual COPVs in service. Any information obtained that clarifies and eliminates uncertainty in these parameters will have a major effect on the predicted reliability of the service COPVs going forward. The key result is that the longer the vessel survives, the more likely the more optimistic stress ratio model is correct. At the time of writing, the resulting effect on predicted future reliability is dramatic, increasing it by about one "nine," that is, reducing the predicted probability of failure by an order of magnitude. However, testing one vessel does not change the uncertainty on the Weibull shape parameter for lifetime since testing several vessels would be necessary.

Wind and Wake Sensing with UAV Formation Flight: System Development and Flight Testing

NASA Astrophysics Data System (ADS)

Larrabee, Trenton Jameson

Wind turbulence including atmospheric turbulence and wake turbulence have been widely investigated; however, only recently it become possible to use Unmanned Aerial Vehicles (UAVs) as a validation tool for research in this area. Wind can be a major contributing factor of adverse weather for aircraft. More importantly, it is an even greater risk towards UAVs because of their small size and weight. Being able to estimate wind fields and gusts can potentially provide substantial benefits for both unmanned and manned aviation. Possible applications include gust suppression for improving handling qualities, a better warning system for high wind encounters, and enhanced control for small UAVs during flight. On the other hand, the existence of wind can be advantageous since it can lead to fuel savings and longer duration flights through dynamic soaring or thermal soaring. Wakes are an effect of the lift distribution across an aircraft's wing or tail. Wakes can cause substantial disturbances when multiple aircraft are moving through the same airspace. In fact, the perils from an aircraft flying through the wake of another aircraft is a leading cause of the delay between takeoff times at airports. Similar to wind, though, wakes can be useful for energy harvesting and increasing an aircraft's endurance when flying in formation which can be a great advantage to UAVs because they are often limited in flight time due to small payload capacity. Formation flight can most often be seen in manned aircraft but can be adopted for use with unmanned systems. Autonomous flight is needed for flying in the "sweet spot" of the generated wakes for energy harvesting as well as for thermal soaring during long duration flights. For the research presented here formation flight was implemented for the study of wake sensing and gust alleviation. The major contributions of this research are in the areas of a novel technique to estimate wind using an Unscented Kalman filter and experimental wake sensing data using UAVs in formation flight. This has been achieved and well documented before in manned aircraft but very little work has been done on UAV wake sensing especially during flight testing. This document describes the development and flight testing of small unmanned aerial system (UAS) for wind and wake sensing purpose including a Ground Control Station (GCS) and UAVs. This research can be stated in four major components. Firstly, formation flight was obtained by integrating a formation flight controller on the WVU Phastball Research UAV aircraft platform from the Flight Control Systems Laboratory (FCSL) at West Virginia University (WVU). Second, a new approach to wind estimation using an Unscented Kalman filter (UKF) is discussed along with results from flight data. Third, wake modeling within a simulator and wake sensing during formation flight is shown. Finally, experimental results are used to discuss the "sweet spot" for energy harvesting in formation flight, a novel approach to cooperative wind estimation, and gust suppression control for a follower aircraft in formation flight.

Model-Based Fault Diagnosis for Turboshaft Engines

NASA Technical Reports Server (NTRS)

Green, Michael D.; Duyar, Ahmet; Litt, Jonathan S.

1998-01-01

Tests are described which, when used to augment the existing periodic maintenance and pre-flight checks of T700 engines, can greatly improve the chances of uncovering a problem compared to the current practice. These test signals can be used to expose and differentiate between faults in various components by comparing the responses of particular engine variables to the expected. The responses can be processed on-line in a variety of ways which have been shown to reveal and identify faults. The combination of specific test signals and on-line processing methods provides an ad hoc approach to the isolation of faults which might not otherwise be detected during pre-flight checkout.

Ames Research Center life sciences payload

NASA Technical Reports Server (NTRS)

Callahan, P. X.; Tremor, J. W.

1982-01-01

In response to a recognized need for an in-flight animal housing facility to support Spacelab life sciences investigators, a rack and system compatible Research Animal Holding Facility (RAHF) has been developed. A series of ground tests is planned to insure its satisfactory performance under certain simulated conditions of flight exposure and use. However, even under the best conditions of simulation, confidence gained in ground testing will not approach that resulting from actual spaceflight operation. The Spacelab Mission 3 provides an opportunity to perform an inflight Verification Test (VT) of the RAHF. Lessons learned from the RAHF-VT and baseline performance data will be invaluable in preparation for subsequent dedicated life sciences missions.

EMC system test performance on Spacelab

NASA Astrophysics Data System (ADS)

Schwan, F.

1982-07-01

Electromagnetic compatibility testing of the Spacelab engineering model is discussed. Documentation, test procedures (including data monitoring and test configuration set up) and performance assessment approach are described. Equipment was assembled into selected representative flight configurations. The physical and functional interfaces between the subsystems were demonstrated within the integration and test sequence which culminated in the flyable configuration Long Module plus one Pallet.

Simulation of a weather radar display for over-water airborne radar approaches

NASA Technical Reports Server (NTRS)

Clary, G. R.

1983-01-01

Airborne radar approach (ARA) concepts are being investigated as a part of NASA's Rotorcraft All-Weather Operations Research Program on advanced guidance and navigation methods. This research is being conducted using both piloted simulations and flight test evaluations. For the piloted simulations, a mathematical model of the airborne radar was developed for over-water ARAs to offshore platforms. This simulated flight scenario requires radar simulation of point targets, such as oil rigs and ships, distributed sea clutter, and transponder beacon replies. Radar theory, weather radar characteristics, and empirical data derived from in-flight radar photographs are combined to model a civil weather/mapping radar typical of those used in offshore rotorcraft operations. The resulting radar simulation is realistic and provides the needed simulation capability for ongoing ARA research.

CFD Predictions of Sonic-Boom Characteristics for Unmodified and Modified SR-71 Configurations

NASA Technical Reports Server (NTRS)

Fouladi, Kamran

1999-01-01

Shaped sonic-boom signatures refer to signatures that look something other than the typical N-waves. Shaped sonic-boom signatures such as "flat-top," "ramp-type," or "hybrid-type" waveforms have been shown to reduce the subjective loudness without requiring reductions in overpressure peaks. The shaping of sonic-boom signatures requires increasing the shock rise time and changes in frequency spectra. So far, a flat-top waveform was shown to be achievable in wind tunnels; however, the influence of long propagation distance and real atmosphere on shaped signatures should be addressed using flight tests. Two different approaches have been proposed for sonic-boom minimization flight tests. The first approach, proposed by Eagle Aerospace, is for a flight test using a modified BQM-34 "FIREBEE" remotely piloted vehicle. The 30-foot long FIREBEE has a steady state flight condition at the Mach number and altitude of interest, and it can be recovered by helicopter from the water. As an alternative approach, a modified SR-71 vehicle has been proposed by the McDonnell Douglas Corporation. Benefits of the SR-71 include its variable geometry supersonic inlets, small cockpit bulge, higher Mach number capabilities, slender design, and longer length (105 foot). The present investigation addresses the sonic-boom analysis for the second vehicle.The objective of the current investigation is to assess the feasibility of a modified SR-71 configuration, with McDonnell Douglas-designed fuselage modifications, intended to produce shaped sonic-boom signatures on the ground. The present study describes the use of a higher-order computational fluid dynamics (CFD) method to predict the sonic-boom characteristics for both unmodified and modified SR-71 configurations. An Euler unstructured grid methodology is used to predict the near-field, three-dimensional pressure patterns generated by both SR-71 models. The computed near-field pressure signatures are extrapolated to specified distances below the aircraft down to impingement on the ground using the code MDBOOM. Comparisons of the near-field pressure signatures with available flight-test data are presented in the current paper.

Coupled Facility-Payload Vibration Modeling Improvements

NASA Technical Reports Server (NTRS)

Carnahan, Timothy M.; Kaiser, Michael A.

2015-01-01

A major phase of aerospace hardware verification is vibration testing. The standard approach for such testing is to use a shaker to induce loads into the payload. In preparation for vibration testing at National Aeronautics and Space Administration/Goddard Space Flight Center an analysis is performed to assess the responses of the payload. A new method of modeling the test is presented that takes into account dynamic interactions between the facility and the payload. This dynamic interaction has affected testing in the past, but been ignored or adjusted for during testing. By modeling the combined dynamics of the facility and test article (payload) it is possible to improve the prediction of hardware responses. Many aerospace test facilities work in similar way to those at NASA/Goddard Space Flight Center. Lessons learned here should be applicable to other test facilities with similar setups.

Terminal area energy management regime investigations utilizing an 0.030-scale model (47-0) of the space shuttle vehicle orbiter configuration 140A/B/C/R in the Ames Research Center 11 x 11 foot transonic wind tunnel (OA148), volume 5

NASA Technical Reports Server (NTRS)

Hawthorne, P. J.

1976-01-01

Data obtained in wind tunnel test OA148 are presented. The objectives of the test series were to: (1) obtain pressure distributions, forces and moments over the vehicle 5 orbiter in the thermal area energy management (TAEM) and approach phases of flight; (2) obtain elevon and rudder hinge moments in the TAEM and approach phases of flight; (3) obtain body flap and elevon loads for verification of loads balancing with integrated pressure distributions; and (4) obtain pressure distributions near the short OMS pods in the high subsonic, transonic and low supersonic Mach number regimes.

Manned remote work station development article

NASA Technical Reports Server (NTRS)

1978-01-01

The two prime objectives of the Manned Remote Work Station (MRWS) Development Article Study are to first, evaluate the MRWS flight article roles and associated design concepts for fundamental requirements and embody key technology developments into a simulation program; and to provide detail manufacturing drawings and schedules for a simulator development test article. An approach is outlined which establishes flight article requirements based on past studies of Solar Power Satellite, orbital construction support equipments, construction bases and near term shuttle operations. Simulation objectives are established for those technology issues that can best be addressed on a simulator. Concepts for full-scale and sub-scale simulators are then studied to establish an overall approach to studying MRWS requirements. Emphasis then shifts to design and specification of a full-scale development test article.

Workload Influence on Fatigue Related Psychological and Physiological Performance Changes of Aviators

PubMed Central

Liu, Xi-Wen; Bian, Ka; Wen, Zhi-Hong; Li, Xiao-Jing; Zhang, Zuo-Ming; Hu, Wen-Dong

2014-01-01

Objective We evaluated a variety of non-invasive physiological technologies and a series of test approaches for examination of aviator performances under conditions of mental workload in order to provide a standard real-time test for physiological and psychological pilot fatigue assessments. Methods Twenty-one male aviators were selected for a simulated flight in a hypobaric cabin with artificial altitude conditions of 2400 meter above sea level. The simulated flight lasted for 1.5 h, and was repeated for two times with an intervening 0.5 h rest period outside the hypobaric cabin. Subjective criteria (a fatigue assessment instrument [FAI]) and objective criteria (a standing-position balance test as well as a critical flicker fusion frequency (CFF) test) were used for fatigue evaluations. Results No significant change was observed in the FAI scores before and after the simulated flight, indicating that there was no subjective fatigue feeling among the participants. However, significant differences were observed in the standing-position balance and CFF tests among the subjects, suggesting that psychophysiological indexes can reflect mental changes caused by workload to a certain extent. The CFF test was the simplest and clearly indicated the occurrence of workload influences on pilot performances after a simulated flight. Conclusions Results showed that the CFF test was the easiest way to detect workload caused mental changes after a simulated flight in a hypobaric cabin and reflected the psychophysiological state of aviators. We suggest that this test might be used as an effective routine method for evaluating the workload influences on mental conditions of aviators. PMID:24505277

A fault-tolerant control architecture for unmanned aerial vehicles

NASA Astrophysics Data System (ADS)

Drozeski, Graham R.

Research has presented several approaches to achieve varying degrees of fault-tolerance in unmanned aircraft. Approaches in reconfigurable flight control are generally divided into two categories: those which incorporate multiple non-adaptive controllers and switch between them based on the output of a fault detection and identification element, and those that employ a single adaptive controller capable of compensating for a variety of fault modes. Regardless of the approach for reconfigurable flight control, certain fault modes dictate system restructuring in order to prevent a catastrophic failure. System restructuring enables active control of actuation not employed by the nominal system to recover controllability of the aircraft. After system restructuring, continued operation requires the generation of flight paths that adhere to an altered flight envelope. The control architecture developed in this research employs a multi-tiered hierarchy to allow unmanned aircraft to generate and track safe flight paths despite the occurrence of potentially catastrophic faults. The hierarchical architecture increases the level of autonomy of the system by integrating five functionalities with the baseline system: fault detection and identification, active system restructuring, reconfigurable flight control; reconfigurable path planning, and mission adaptation. Fault detection and identification algorithms continually monitor aircraft performance and issue fault declarations. When the severity of a fault exceeds the capability of the baseline flight controller, active system restructuring expands the controllability of the aircraft using unconventional control strategies not exploited by the baseline controller. Each of the reconfigurable flight controllers and the baseline controller employ a proven adaptive neural network control strategy. A reconfigurable path planner employs an adaptive model of the vehicle to re-shape the desired flight path. Generation of the revised flight path is posed as a linear program constrained by the response of the degraded system. Finally, a mission adaptation component estimates limitations on the closed-loop performance of the aircraft and adjusts the aircraft mission accordingly. A combination of simulation and flight test results using two unmanned helicopters validates the utility of the hierarchical architecture.

Degradation of learned skills. Static practice effectiveness for visual approach and landing skill retention

NASA Technical Reports Server (NTRS)

Sitterley, T. E.

1974-01-01

The effectivess of an improved static retraining method was evaluated for a simulated space vehicle approach and landing under instrument and visual flight conditions. Experienced pilots were trained and then tested after 4 months without flying to compare their performance using the improved method with three methods previously evaluated. Use of the improved static retraining method resulted in no practical or significant skill degradation and was found to be even more effective than methods using a dynamic presentation of visual cues. The results suggested that properly structured open loop methods of flight control task retraining are feasible.

Flight Avionics Sequencing Telemetry (FAST) DIV Latching Display

NASA Technical Reports Server (NTRS)

Moore, Charlotte

2010-01-01

The NASA Engineering (NE) Directorate at Kennedy Space Center provides engineering services to major programs such as: Space Shuttle, Inter national Space Station, and the Launch Services Program (LSP). The Av ionics Division within NE, provides avionics and flight control syste ms engineering support to LSP. The Launch Services Program is respons ible for procuring safe and reliable services for transporting critical, one of a kind, NASA payloads into orbit. As a result, engineers mu st monitor critical flight events during countdown and launch to asse ss anomalous behavior or any unexpected occurrence. The goal of this project is to take a tailored Systems Engineering approach to design, develop, and test Iris telemetry displays. The Flight Avionics Sequen cing Telemetry Delta-IV (FAST-D4) displays will provide NASA with an improved flight event monitoring tool to evaluate launch vehicle heal th and performance during system-level ground testing and flight. Flight events monitored will include data from the Redundant Inertial Fli ght Control Assembly (RIFCA) flight computer and launch vehicle comma nd feedback data. When a flight event occurs, the flight event is ill uminated on the display. This will enable NASA Engineers to monitor c ritical flight events on the day of launch. Completion of this project requires rudimentary knowledge of launch vehicle Guidance, Navigatio n, and Control (GN&C) systems, telemetry, and console operation. Work locations for the project include the engineering office, NASA telem etry laboratory, and Delta launch sites.

Quiet Spike Build-Up Ground Vibration Testing Approach

NASA Technical Reports Server (NTRS)

Spivey, Natalie D.; Herrera, Claudia Y.; Truax, Roger; Pak, Chan-gi; Freund, Donald

2007-01-01

NASA's Dryden Flight Research Center uses a modified F-15B (836) aircraft as a testbed for a variety of flight research:experiments mounted underneath the aircraft fuselage. The F-15B was selected to fly Gulfstream Aerospace Corporation's (GAC)QuietSpike(TM)(QS) project; however, this experiment is very unique and unlike any of the previous testbed experiments flown on the F-15B. It involves the addition of a relatively long quiet spike boom attached to the radar bulkhead of the aircraft. This QS experiment is a stepping stone to airframe structural morphing technologies designed to mitigate sonic born strength of business jets over land. The QS boom is a concept in Which an aircraft's front-end would be extended prior to supersonic acceleration. This morphing would effectively lengthen the aircraft, reducing peak sonic boom amplitude, but is also expected to partition the otherwise strong bow shock into a series of reduced-strength, non-coalescing shocklets. Prior to flying the Quietspike(TM) experiment on the F-15B aircraft several ground vibration tests (GVT) were required in order to understand the QS modal characteristics and coupling effects with the F-15B. However, due to the project's late hardware delivery of the QS and the intense schedule, a "traditional" GVT of the mated F-1513 Quietspike(tm) ready-for-flight configuration would not have left sufficient time available for the finite element model update and flutter analyses before flight testing. Therefore, a "nontraditional" ground vibration testing approach was taken. The objective of the QuietSpike (TM) build-up ground testing approach was to ultimately obtain confidence in the F-15B Quietspike(TM) finite element model (FEM) to be used for the flutter analysis. In order to obtain the F15B QS FEM with reliable foundation stiffness between the QS and the F-15B radar bulkhead as well as QS modal characteristics, several different GVT configurations were performed. EAch of the four GVT's performed had a specific objective. The overall intent was to provide adequate data which would replicate a "traditional" F-15B QS GVT with actual ready-for-flight hardware. NASA Dryden was tasked with the conduct of the 1st, 2nd and 4th GVT and the 3rd GVT was GAC's responsibility. In order for this build-up GVT approach to be feasible, it was absolutely critical that each GVT configuration matched as closely as possible the connection interface configuration between the and aircraft bulkhead.

Synergistic Development, Test, and Qualification Approaches for the Ares I and V Launch Vehicles

NASA Technical Reports Server (NTRS)

Cockrell, Charles E.; Taylor, James L.; Patterson, Alan; Stephens, Samuel E.; Tuma, Margaret; Bartolotta, Paul; Huetter, Uwe; Kaderback, Don; Goggin, David

2009-01-01

The U.S. National Aeronautics and Space Administration (NASA) initiated plans to develop the Ares I and Ares V launch vehicles in 2005 to meet the mission objectives for future human exploration of space. Ares I is designed to provide the capability to deliver the Orion crew exploration vehicle (CEV) to low-Earth orbit (LEO), either for docking to the International Space Station (ISS) or docking with an Earth departure stage (EDS) and lunar lander for transit to the Moon. Ares V provides the heavy-lift capability to deliver the EDS and lunar lander to orbit. An integrated test plan was developed for Ares I that includes un-crewed flight validation testing and ground testing to qualify structural components and propulsion systems prior to operational deployment. The overall test program also includes a single development test flight conducted prior to the Ares I critical design review (CDR). Since the Ares V concept was formulated to maximize hardware commonality between the Ares V and Ares I launch vehicles, initial test planning for Ares V has considered the extensibility of test approaches and facilities from Ares I. The Ares V test plan was part of a successful mission concept review (MCR) in 2008.

Vision based flight procedure stereo display system

NASA Astrophysics Data System (ADS)

Shen, Xiaoyun; Wan, Di; Ma, Lan; He, Yuncheng

2008-03-01

A virtual reality flight procedure vision system is introduced in this paper. The digital flight map database is established based on the Geographic Information System (GIS) and high definitions satellite remote sensing photos. The flight approaching area database is established through computer 3D modeling system and GIS. The area texture is generated from the remote sensing photos and aerial photographs in various level of detail. According to the flight approaching procedure, the flight navigation information is linked to the database. The flight approaching area vision can be dynamic displayed according to the designed flight procedure. The flight approaching area images are rendered in 2 channels, one for left eye images and the others for right eye images. Through the polarized stereoscopic projection system, the pilots and aircrew can get the vivid 3D vision of the flight destination approaching area. Take the use of this system in pilots preflight preparation procedure, the aircrew can get more vivid information along the flight destination approaching area. This system can improve the aviator's self-confidence before he carries out the flight mission, accordingly, the flight safety is improved. This system is also useful in validate the visual flight procedure design, and it helps to the flight procedure design.

Frictional Ignition Testing of Composite Materials

NASA Technical Reports Server (NTRS)

Peralta, Steve; Rosales, Keisa; Robinson, Michael J.; Stoltzfus, Joel

2006-01-01

The space flight community has been investigating lightweight composite materials for use in propellant tanks for both liquid and gaseous oxygen for space flight vehicles. The use of these materials presents some risks pertaining to ignition and burning hazards in the presence of oxygen. Through hazard analysis process, some ignition mechanisms have been identified as being potentially credible. One of the ignition mechanisms was reciprocal friction; however, test data do not exist that could be used to clear or fail these types of materials as "oxygen compatible" for the reciprocal friction ignition mechanism. Therefore, testing was performed at White Sands Test Facility (WSTF) to provide data to evaluate this ignition mechanism. This paper presents the test system, approach, data results, and findings of the reciprocal friction testing performed on composite sample materials being considered for propellant tanks.

Evaluation of the usefulness of various simulation technology options for TERPS enhancement

NASA Technical Reports Server (NTRS)

Phatak, A. V.; Sorensen, J. A.

1986-01-01

Current approved terminal instrument procedures (TERPS) do not permit the full exploitation of the helicopter's unique flying characteristics. Enhanced TERPS need to be developed for a host of non-standard landing sites and navigation aids. Precision navigation systems such as microwave landing systems (MLS) and the Global Positioning System (GPS) open the possibility of curved paths, steep glide slopes, and decelerating helicopter approaches. This study evaluated the feasibility, benefits, and liabilities of using helicopter cockpit simulators in place of flight testing to develop enhanced TERPS criteria for non-standard flight profiles and navigation equipment. Near-term (2 to 5 year) requirements for conducting simulator studies to verify that they produce suitable data comparable to that obtained from previous flight tests are discussed. The long-term (5 to 10 year) research and development requirements to provide necessary modeling for continued simulator-based testing to develop enhanced TERPS criteria are also outlined.

Using Vision System Technologies for Offset Approaches in Low Visibility Operations

NASA Technical Reports Server (NTRS)

Kramer, Lynda J.; Bailey, Randall E.; Ellis, Kyle K.

2015-01-01

Flight deck-based vision systems, such as Synthetic Vision Systems (SVS) and Enhanced Flight Vision Systems (EFVS), have the potential to provide additional margins of safety for aircrew performance and enable the implementation of operational improvements for low visibility surface, arrival, and departure operations in the terminal environment with equivalent efficiency to visual operations. Twelve air transport-rated crews participated in a motion-base simulation experiment to evaluate the use of SVS/EFVS in Next Generation Air Transportation System low visibility approach and landing operations at Chicago O'Hare airport. Three monochromatic, collimated head-up display (HUD) concepts (conventional HUD, SVS HUD, and EFVS HUD) and three instrument approach types (straight-in, 3-degree offset, 15-degree offset) were experimentally varied to test the efficacy of the SVS/EFVS HUD concepts for offset approach operations. The findings suggest making offset approaches in low visibility conditions with an EFVS HUD or SVS HUD appear feasible. Regardless of offset approach angle or HUD concept being flown, all approaches had comparable ILS tracking during the instrument segment and were within the lateral confines of the runway with acceptable sink rates during the visual segment of the approach. Keywords: Enhanced Flight Vision Systems; Synthetic Vision Systems; Head-up Display; NextGen

Flight management research utilizing an oculometer. [pilot scanning behavior during simulated approach and landing

NASA Technical Reports Server (NTRS)

Spady, A. A., Jr.; Kurbjun, M. C.

1978-01-01

This paper presents an overview of the flight management work being conducted using NASA Langley's oculometer system. Tests have been conducted in a Boeing 737 simulator to investigate pilot scan behavior during approach and landing for simulated IFR, VFR, motion versus no motion, standard versus advanced displays, and as a function of various runway patterns and symbology. Results of each of these studies are discussed. For example, results indicate that for the IFR approaches a difference in pilot scan strategy was noted for the manual versus coupled (autopilot) conditions. Also, during the final part of the approach when the pilot looks out-of-the-window he fixates on his aim or impact point on the runway and holds this point until flare initiation.

A Flight Control Approach for Small Reentry Vehicles

NASA Technical Reports Server (NTRS)

Bevacqoa, Tim; Adams, Tony; Zhu. J. Jim; Rao, P. Prabhakara

2004-01-01

Flight control of small crew return vehicles during atmospheric reentry will be an important technology in any human space flight mission undertaken in the future. The control system presented in this paper is applicable to small crew return vehicles in which reaction control system (RCS) thrusters are the only actuators available for attitude control. The control system consists of two modules: (i) the attitude controller using the trajectory linearization control (TLC) technique, and (ii) the reaction control system (RCS) control allocation module using a dynamic table-lookup technique. This paper describes the design and implementation of the TLC attitude control and the dynamic table-lookup RCS control allocation for nonimal flight along with design verification test results.

Performance analysis of mini-propellers based on FlightGear

NASA Astrophysics Data System (ADS)

Vogeltanz, Tomáš

2016-06-01

This paper presents a performance analysis of three mini-propellers based on the FlightGear flight simulator. Although a basic propeller analysis has to be performed before the use of FlightGear, for a complex and more practical performance analysis, it is advantageous to use a propeller model in cooperation with a particular aircraft model. This approach may determine whether the propeller has sufficient quality in respect of aircraft requirements. In the first section, the software used for the analysis is illustrated. Then, the parameters of the analyzed mini-propellers and the tested UAV are described. Finally, the main section shows and discusses the results of the performance analysis of the mini-propellers.

SNC's Dream Chaser Arrives at NASA Armstrong

NASA Image and Video Library

2017-03-08

This 58-second video shows Sierra Nevada Corporation (SNC) delivering its Dream Chaser spacecraft on Jan. 25, 2017, to NASA's Armstrong Flight Research Center in California, located on Edwards Air Force Base. The spacecraft will undergo several months of testing at the Center in preparation for its approach and landing flight on the base's runway. The test series is part of a developmental space act agreement SNC has with NASA’s HYPERLINK Commercial Crew Program. The upcoming test campaign will help SNC validate the aerodynamic properties, flight software and control system performance of the Dream Chaser. The Dream Chaser is also being prepared to deliver cargo to the International Space Station under NASA’s Commercial Resupply Services 2 (CRS2) contract beginning in 2019. The data that SNC gathers from this test campaign will help influence and inform the final design of the cargo Dream Chaser, which will fly at least six cargo delivery missions to and from the Space Station by 2024.

Early flight test experience with Cockpit Displayed Traffic Information (CDTI)

NASA Technical Reports Server (NTRS)

Abbott, T. S.; Moen, G. C.; Person, L. H., Jr.; Keyser, G. L., Jr.; Yenni, K. R.; Garren, J. F., Jr.

1980-01-01

Coded symbology, based on the results of early human factors studies, was displayed on the electronic horizontal situation indicator and flight tested on an advanced research aircraft in order to subject the coded traffic symbology to a realistic flight environment and to assess its value by means of a direct comparison with simple, uncoded traffic symbology. The tests consisted of 28 curved, decelerating approaches, flown by research-pilot flight crews. The traffic scenarios involved both conflict-free and blunder situations. Subjective pilot commentary was obtained through the use of a questionnaire and extensive pilot debriefing sessions. The results of these debriefing sessions group conveniently under either of two categories: display factors or task performance. A major item under the display factor category was the problem of display clutter. The primary contributors to clutter were the use of large map-scale factors, the use of traffic data blocks, and the presentation of more than a few aircraft. In terms of task performance, the cockpit displayed traffic information was found to provide excellent overall situation awareness.

KSC-2014-3665

NASA Image and Video Library

2014-08-25

CAPE CANAVERAL, Fla. – The umbilical swing arm for Orion's Exploration Flight Test 1, or EFT-1, has been attached to the uppermost location on the fixed umbilical tower at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. All three swing arms on the tower are undergoing tests to confirm that they are operating correctly. They are being swung out and closer to the Vertical Integration Facility at the pad. The uppermost swing arm will carry umbilicals that will be mated to Orion's launch abort system and environmental control system. During launch, all three umbilicals will pull away from Orion and the United Launch Alliance Delta IV Heavy rocket at T-0. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on its first flight test is planned for fall 2014. Photo credit: NASA/Daniel Casper

KSC-2014-3664

NASA Image and Video Library

2014-08-25

CAPE CANAVERAL, Fla. – The umbilical swing arm for Orion's Exploration Flight Test 1, or EFT-1, has been attached to the uppermost location on the fixed umbilical tower at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. All three swing arms on the tower are undergoing tests to confirm that they are operating correctly. They are being swung out and closer to the Vertical Integration Facility at the pad. The uppermost swing arm will carry umbilicals that will be mated to Orion's launch abort system and environmental control system. During launch, all three umbilicals will pull away from Orion and the United Launch Alliance Delta IV Heavy rocket at T-0. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on its first flight test is planned for fall 2014. Photo credit: NASA/Daniel Casper

KSC-2014-3667

NASA Image and Video Library

2014-08-25

CAPE CANAVERAL, Fla. – The umbilical swing arm for Orion's Exploration Flight Test 1, or EFT-1, has been attached to the uppermost location on the fixed umbilical tower at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. All three swing arms on the tower are undergoing tests to confirm that they are operating correctly. They are being swung out and closer to the Vertical Integration Facility at the pad. The uppermost swing arm will carry umbilicals that will be mated to Orion's launch abort system and environmental control system. During launch, all three umbilicals will pull away from Orion and the United Launch Alliance Delta IV Heavy rocket at T-0. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on its first flight test is planned for fall 2014. Photo credit: NASA/Daniel Casper

KSC-2014-3663

NASA Image and Video Library

2014-08-25

CAPE CANAVERAL, Fla. – The umbilical swing arm for Orion's Exploration Flight Test 1, or EFT-1, has been attached to the uppermost location on the fixed umbilical tower at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. All three swing arms on the tower are undergoing tests to confirm that they are operating correctly. They are being swung out and closer to the Vertical Integration Facility at the pad. The uppermost swing arm will carry umbilicals that will be mated to Orion's launch abort system and environmental control system. During launch, all three umbilicals will pull away from Orion and the United Launch Alliance Delta IV Heavy rocket at T-0. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on its first flight test is planned for fall 2014. Photo credit: NASA/Daniel Casper

KSC-2014-3666

NASA Image and Video Library

2014-08-25

CAPE CANAVERAL, Fla. – The umbilical swing arm for Orion's Exploration Flight Test 1, or EFT-1, has been attached to the uppermost location on the fixed umbilical tower at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. All three swing arms on the tower are undergoing tests to confirm that they are operating correctly. They are being swung out and closer to the Vertical Integration Facility at the pad. The uppermost swing arm will carry umbilicals that will be mated to Orion's launch abort system and environmental control system. During launch, all three umbilicals will pull away from Orion and the United Launch Alliance Delta IV Heavy rocket at T-0. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on its first flight test is planned for fall 2014. Photo credit: NASA/Daniel Casper

Abort Flight Test Project Overview

NASA Technical Reports Server (NTRS)

Sitz, Joel

2007-01-01

A general overview of the Orion abort flight test is presented. The contents include: 1) Abort Flight Test Project Overview; 2) DFRC Exploration Mission Directorate; 3) Abort Flight Test; 4) Flight Test Configurations; 5) Flight Test Vehicle Engineering Office; 6) DFRC FTA Scope; 7) Flight Test Operations; 8) DFRC Ops Support; 9) Launch Facilities; and 10) Scope of Launch Abort Flight Test

Photonic Component Qualification and Implementation Activities at NASA Goddard Space Flight Center

NASA Technical Reports Server (NTRS)

Ott, Melanie N.; Jin, Xiaodan Linda; Chuska, Richard F.; LaRocca, Frank V.; MacMurphy, Shawn L.; Matuszeski, Adam J.; Zellar, Ronald S.; Friedberg, Patricia R.; Malenab, Mary C.

2006-01-01

The photonics group in Code 562 at NASA Goddard Space Flight Center supports a variety of space flight programs at NASA including the: International Space Station (ISS), Shuttle Return to Flight Mission, Lunar Reconnaissance Orbiter (LRO), Express Logistics Carrier, and the NASA Electronic Parts and Packaging Program (NEPP). Through research, development, and testing of the photonic systems to support these missions much information has been gathered on practical implementations for space environments. Presented here are the highlights and lessons learned as a result of striving to satisfy the project requirements for high performance and reliable commercial optical fiber components for space flight systems. The approach of how to qualify optical fiber components for harsh environmental conditions, the physics of failure and development lessons learned will be discussed.

Performance, physiological, and oculometer evaluation of VTOL landing displays

NASA Technical Reports Server (NTRS)

North, R. A.; Stackhouse, S. P.; Graffunder, K.

1979-01-01

A methodological approach to measuring workload was investigated for evaluation of new concepts in VTOL aircraft displays. Physiological, visual response, and conventional flight performance measures were recorded for landing approaches performed in the NASA Visual Motion Simulator (VMS). Three displays (two computer graphic and a conventional flight director), three crosswind amplitudes, and two motion base conditions (fixed vs. moving base) were tested in a factorial design. Multivariate discriminant functions were formed from flight performance and/or visual response variables. The flight performance variable discriminant showed maximum differentation between crosswind conditions. The visual response measure discriminant maximized differences between fixed vs. motion base conditions and experimental displays. Physiological variables were used to attempt to predict the discriminant function values for each subject/condition trial. The weights of the physiological variables in these equations showed agreement with previous studies. High muscle tension, light but irregular breathing patterns, and higher heart rate with low amplitude all produced higher scores on this scale and thus represent higher workload levels.

Optimal Control Allocation with Load Sensor Feedback for Active Load Suppression, Flight-Test Performance

NASA Technical Reports Server (NTRS)

Miller, Christopher J.; Goodrick, Dan

2017-01-01

The problem of control command and maneuver induced structural loads is an important aspect of any control system design. The aircraft structure and the control architecture must be designed to achieve desired piloted control responses while limiting the imparted structural loads. The classical approach is to utilize high structural margins, restrict control surface commands to a limited set of analyzed combinations, and train pilots to follow procedural maneuvering limitations. With recent advances in structural sensing and the continued desire to improve safety and vehicle fuel efficiency, it is both possible and desirable to develop control architectures that enable lighter vehicle weights while maintaining and improving protection against structural damage. An optimal control technique has been explored and shown to achieve desirable vehicle control performance while limiting sensed structural loads to specified values. This technique has been implemented and flown on the National Aeronautics and Space Administration Full-scale Advanced Systems Testbed aircraft. The flight tests illustrate that the approach achieves the desired performance and show promising potential benefits. The flights also uncovered some important issues that will need to be addressed for production application.

Sierra Nevada Corporation (SNC) Dream Chaser arrival at Armstron

NASA Image and Video Library

2017-01-25

Sierra Nevada Corporation’s Dream Chaser spacecraft is removed from its delivery truck after arriving at NASA’s Armstrong Flight Research Center in California, located on Edwards Air Force Base. The spacecraft will undergo several months of testing in preparation for its approach and landing flight on the base’s 22L runway. The test series is part of a developmental space act agreement SNC has with NASA’s Commercial Crew Program and will help SNC validate aerodynamic properties, flight software and control system performance. The Dream Chaser is also being prepared to deliver cargo to the International Space Station under NASA’s Commercial Resupply Services 2 contract beginning in 2019. The cargo Dream Chaser will fly at least six delivery missions to and from the space station by 2024.

A GPS-Based Pitot-Static Calibration Method Using Global Output-Error Optimization

NASA Technical Reports Server (NTRS)

Foster, John V.; Cunningham, Kevin

2010-01-01

Pressure-based airspeed and altitude measurements for aircraft typically require calibration of the installed system to account for pressure sensing errors such as those due to local flow field effects. In some cases, calibration is used to meet requirements such as those specified in Federal Aviation Regulation Part 25. Several methods are used for in-flight pitot-static calibration including tower fly-by, pacer aircraft, and trailing cone methods. In the 1990 s, the introduction of satellite-based positioning systems to the civilian market enabled new inflight calibration methods based on accurate ground speed measurements provided by Global Positioning Systems (GPS). Use of GPS for airspeed calibration has many advantages such as accuracy, ease of portability (e.g. hand-held) and the flexibility of operating in airspace without the limitations of test range boundaries or ground telemetry support. The current research was motivated by the need for a rapid and statistically accurate method for in-flight calibration of pitot-static systems for remotely piloted, dynamically-scaled research aircraft. Current calibration methods were deemed not practical for this application because of confined test range size and limited flight time available for each sortie. A method was developed that uses high data rate measurements of static and total pressure, and GPSbased ground speed measurements to compute the pressure errors over a range of airspeed. The novel application of this approach is the use of system identification methods that rapidly compute optimal pressure error models with defined confidence intervals in nearreal time. This method has been demonstrated in flight tests and has shown 2- bounds of approximately 0.2 kts with an order of magnitude reduction in test time over other methods. As part of this experiment, a unique database of wind measurements was acquired concurrently with the flight experiments, for the purpose of experimental validation of the optimization method. This paper describes the GPS-based pitot-static calibration method developed for the AirSTAR research test-bed operated as part of the Integrated Resilient Aircraft Controls (IRAC) project in the NASA Aviation Safety Program (AvSP). A description of the method will be provided and results from recent flight tests will be shown to illustrate the performance and advantages of this approach. Discussion of maneuver requirements and data reduction will be included as well as potential applications.

PHYSX Glove Test

NASA Technical Reports Server (NTRS)

1995-01-01

A mock-up of the stainless-steel Pegasus Hypersonic Experiment (PHYSX) Projects experimental 'glove' undergoes hot-loads tests at NASA's Dryden Flight Research Center, Edwards, California. The thermal ground test simulates heats and pressures the wing glove will experience at hypersonic speeds. Quartz heat lamps subject this model of a Pegasus booster rocket's right wing glove to the extreme heats it will experience at speeds approaching Mach 8. The glove has a highly reflective surface, underneath which are hundreds of temperature and pressure sensors that will send hypersonic flight data to ground tracking facilities during the experimental flight. Pegasus is an air-launched space booster produced by Orbital Sciences Corporation and Hercules Aerospace Company (initially; later, Alliant Tech Systems) to provide small satellite users with a cost-effective, flexible, and reliable method for placing payloads into low earth orbit. Pegasus has been used to launch a number of satellites and the PHYSX experiment. That experiment consisted of a smooth glove installed on the first-stage delta wing of the Pegasus. The glove was used to gather data at speeds of up to Mach 8 and at altitudes approaching 200,000 feet. The flight took place on October 22, 1998. The PHYSX experiment focused on determining where boundary-layer transition occurs on the glove and on identifying the flow mechanism causing transition over the glove. Data from this flight-research effort included temperature, heat transfer, pressure measurements, airflow, and trajectory reconstruction. Hypersonic flight-research programs are an approach to validate design methods for hypersonic vehicles (those that fly more than five times the speed of sound, or Mach 5). Dryden Flight Research Center, Edwards, California, provided overall management of the glove experiment, glove design, and buildup. Dryden also was responsible for conducting the flight tests. Langley Research Center, Hampton, Virginia, was responsible for the design of the aerodynamic glove as well as development of sensor and instrumentation systems for the glove. Other participating NASA centers included Ames Research Center, Mountain View, California; Goddard Space Flight Center, Greenbelt, Maryland; and Kennedy Space Center, Florida. Orbital Sciences Corporation, Dulles, Virginia, is the manufacturer of the Pegasus vehicle, while Vandenberg Air Force Base served as a pre-launch assembly facility for the launch that included the PHYSX experiment. NASA used data from Pegasus launches to obtain considerable data on aerodynamics. By conducting experiments in a piggyback mode on Pegasus, some critical and secondary design and development issues were addressed at hypersonic speeds. The vehicle was also used to develop hypersonic flight instrumentation and test techniques. NASA's B-52 carrier-launch vehicle was used to get the Pegasus airborne during six launches from 1990 to 1994. Thereafter, an Orbital Sciences L-1011 aircraft launched the Pegasus. The Pegasus launch vehicle itself has a 400- to 600-pound payload capacity in a 61-cubic-foot payload space at the front of the vehicle. The vehicle is capable of placing a payload into low earth orbit. This vehicle is 49 feet long and 50 inches in diameter. It has a wing span of 22 feet. (There is also a Pegasus XL vehicle that was introduced in 1994. Dryden has never launched one of these vehicles, but they have greater thrust and are 56 feet long.)

Marshall Space Flight Center ECLSS technology activities

NASA Technical Reports Server (NTRS)

Wieland, Paul

1990-01-01

Viewgraphs on Environmental Control and Life Support System (ECLSS) technology activities are presented. Topics covered include: analytical development; ECLSS modeling approach; example of water reclamation modeling needs; and hardware development and testing.

Design, analysis, and control of large transport aircraft utilizing engine thrust as a backup system for the primary flight controls

NASA Technical Reports Server (NTRS)

Gerren, Donna S.

1993-01-01

A review of accidents that involved the loss of hydraulic flight control systems serves as an introduction to this project. In each of the accidents--involving transport aircraft such as the DC-10, the C-5A, the L-1011, and the Boeing 747--the flight crew attempted to control the aircraft by means of thrust control. Although these incidents had tragic endings, in the absence of control power due to primary control system failure, control power generated by selective application of engine thrust has proven to be a viable alternative. NASA Dryden has demonstrated the feasibility of controlling an aircraft during level flight, approach, and landing conditions using an augmented throttles-only control system. This system has been successfully flown in the flight test simulator for the B-720 passenger transport and the F-15 air superiority fighter and in actual flight tests for the F-15 aircraft. The Douglas Aircraft Company is developing a similar system for the MD-11 aircraft. The project's ultimate goal is to provide data for the development of thrust control systems for mega-transports (600+ passengers).

Flight Team Development in Support of LCROSS - A Class D Mission

NASA Technical Reports Server (NTRS)

Tompkins, Paul D.; Hunt, Rusty; Bresina, John; Galal, Ken; Shirley, Mark; Munger, James; Sawyer, Scott

2010-01-01

The LCROSS (Lunar Crater Observation and Sensing Satellite) project presented a number of challenges to the preparation for mission operations. A class D mission under NASA s risk tolerance scale, LCROSS was governed by a $79 million cost cap and a 29 month schedule from "authority to proceed" to flight readiness. LCROSS was NASA Ames Research Center s flagship mission in its return to spacecraft flight operations after many years of pursuing other strategic goals. As such, ARC needed to restore and update its mission support infrastructure, and in parallel, the LCROSS project had to newly define operational practices and to select and train a flight team combining experienced operators and staff from other arenas of ARC research. This paper describes the LCROSS flight team development process, which deeply involved team members in spacecraft and ground system design, implementation and test; leveraged collaborations with strategic partners; and conducted extensive testing and rehearsals that scaled in realism and complexity in coordination with ground system and spacecraft development. As a testament to the approach, LCROSS successfully met its full mission objectives, despite many in-flight challenges, with its impact on the lunar south pole on October 9, 2009.

Testing flight software on the ground: Introducing the hardware-in-the-loop simulation method to the Alpha Magnetic Spectrometer on the International Space Station

NASA Astrophysics Data System (ADS)

Sun, Wenhao; Cai, Xudong; Meng, Qiao

2016-04-01

Complex automatic protection functions are being added to the onboard software of the Alpha Magnetic Spectrometer. A hardware-in-the-loop simulation method has been introduced to overcome the difficulties of ground testing that are brought by hardware and environmental limitations. We invented a time-saving approach by reusing the flight data as the data source of the simulation system instead of mathematical models. This is easy to implement and it works efficiently. This paper presents the system framework, implementation details and some application examples.

Overview of medical operations for a manned stratospheric balloon flight.

PubMed

Blue, Rebecca S; Law, Jennifer; Norton, Sean C; Garbino, Alejandro; Pattarini, James M; Turney, Matthew W; Clark, Jonathan B

2013-03-01

Red Bull Stratos was a commercial program designed to bring a test parachutist protected by a full-pressure suit via a stratospheric balloon with a pressurized capsule to 120,000 ft (36,576 m), from which he would freefall and subsequently parachute to the ground. On March 15, 2012, the Red Bull Stratos program successfully conducted a preliminary manned balloon test flight and parachute jump, reaching a final altitude of 71,581 ft (21,818 m). In light of the uniqueness of the operation and medical threats faced, a comprehensive medical plan was needed to ensure prompt and efficient response to any medical contingencies. This report will serve to discuss the medical plans put into place before the first manned balloon flight and the actions of the medical team during that flight. The medical operations developed for this program will be systematically evaluated, particularly, specific recommendations for improvement in future high-altitude and commercial space activities. A multipronged approach to medical support was developed, consisting of event planning, medical personnel, equipment, contingency-specific considerations, and communications. Medical operations were found to be highly successful when field-tested during this stratospheric flight, and the experience allowed for refinement of medical operations for future flights. The lessons learned and practices established for this program can easily be used to tailor a plan specific to other aviation or spaceflight events.

Innovative Test Operations to Support Orion and Future Human Rated Missions

NASA Technical Reports Server (NTRS)

Koenig, William J.; Garcia, Rafael; Harris, Richard F.; See, Michael J.; Van Lear, Benjamin S.; Dobson, Jill M.; Norris, Scott Douglas

2017-01-01

This paper describes how the Orion program is implementing new and innovative test approaches and strategies in an evolving development environment. The early flight test spacecraft are evolving in design maturity and complexity requiring significant changes in the ground test operations for each mission. The testing approach for EM-2 is planned to validate innovative Orion production acceptance testing methods to support human exploration missions in the future. Manufacturing and testing at Kennedy Space Center in the Neil Armstrong Operations and Checkout facility will provide a seamless transition directly to the launch site avoiding transportation and checkout of the spacecraft from other locations.

Numerical and flight simulator test of the flight deterioration concept

NASA Technical Reports Server (NTRS)

Mccarthy, J.; Norviel, V.

1982-01-01

Manned flight simulator response to theoretical wind shear profiles was studied in an effort to calibrate fixed-stick and pilot-in-the-loop numerical models of jet transport aircraft on approach to landing. Results of the study indicate that both fixed-stick and pilot-in-the-loop models overpredict the deleterious effects of aircraft approaches when compared to pilot performance in the manned simulator. Although the pilot-in-the-loop model does a better job than does the fixed-stick model, the study suggests that the pilot-in-the-loop model is suitable for use in meteorological predictions of adverse low-level wind shear along approach and departure courses to identify situations in which pilots may find difficulty. The model should not be used to predict the success or failure of a specific aircraft. It is suggested that the pilot model be used as part of a ground-based Doppler radar low-level wind shear detection and warning system.

Comparison of Wind-Tunnel and Flight Measurements of Stability and Control Characteristics of a Douglas A-26 Airplane

NASA Technical Reports Server (NTRS)

Kayten, Gerald G; Koven, William

1945-01-01

Stability and control characteristics determined from tests in the Langley 19-foot pressure tunnel of a 0.2375-scale model of the Douglas XA-26 airplane are compared with those measured in flight tests of a Douglas A-26 airplane. Agreement regarding static longitudinal stability as indicated by the elevator-fixed neutral points and by the variation of elevator deflection in both straight and turning flight was found to be good except at speeds approaching the stall. At these low speeds the airplane possessed noticeably improved stability, which was attributed to pronounced stalling at the root of the production wing. The pronounced root stalling did not occur on the smooth, well-faired model wing. Elevator tab effectiveness determined from model tests agreed well with flight-test tab effectiveness, but control-force variations with speed and acceleration were not in good agreement. The use of model hinge-moment data obtained at zero sideslip appeared to be satisfactory for the determination of aileron forces in sideslip. Fairly good correlation in aileron effectiveness and control forces was obtained; fabric distortion may have been responsible to some extent for higher flight values of aileron force at high speeds. Estimation of sideslip developed in an abrupt aileron roll was fair, but determination of the rudder deflection required to maintain zero sideslip in a rapid aileron roll was not entirely satisfactory.

Stability and Control Analysis of the F-15B Quiet SpikeTM Aircraft

NASA Technical Reports Server (NTRS)

McWherter, Shaun C.; Moua, Cheng M.; Gera, Joseph; Cox, Timothy H.

2009-01-01

The primary purpose of the Quiet Spike(TradeMark) flight research program was to analyze the aerodynamic, structural, and mechanical proof-of-concept of a large multi-stage telescoping nose spike installed on the National Aeronautics and Space Administration Dryden Flight Research Center (Edwards, California) F-15B airplane. This report describes the preflight stability and control analysis performed to assess the effect of the spike on the stability, controllability, and handling qualities of the airplane; and to develop an envelope expansion approach to maintain safety of flight. The overall flight test objective was to collect flight data to validate the spike structural dynamics and loads model up to Mach 1.8. Other objectives included validating the mechanical feasibility of a morphing fuselage at operational conditions and determining the near-field shock wave characterization. The two main issues relevant to the stability and control objectives were the effects of the spike-influenced aerodynamics on the F-15B airplane flight dynamics, and the air data and angle-of-attack sensors. The analysis covered the sensitivity of the stability margins, and the handling qualities due to aerodynamic variation and the maneuvering limitations of the F-15B Quiet Spike configuration. The results of the analysis and the implications for the flight test program are also presented.

Structural dynamic model obtained from flight use with piloted simulation and handling qualities analysis

NASA Technical Reports Server (NTRS)

Powers, Bruce G.

1996-01-01

The ability to use flight data to determine an aircraft model with structural dynamic effects suitable for piloted simulation. and handling qualities analysis has been developed. This technique was demonstrated using SR-71 flight test data. For the SR-71 aircraft, the most significant structural response is the longitudinal first-bending mode. This mode was modeled as a second-order system, and the other higher order modes were modeled as a time delay. The distribution of the modal response at various fuselage locations was developed using a uniform beam solution, which can be calibrated using flight data. This approach was compared to the mode shape obtained from the ground vibration test, and the general form of the uniform beam solution was found to be a good representation of the mode shape in the areas of interest. To calibrate the solution, pitch-rate and normal-acceleration instrumentation is required for at least two locations. With the resulting structural model incorporated into the simulation, a good representation of the flight characteristics was provided for handling qualities analysis and piloted simulation.

Flying the orbiter in the approach/landing phase

NASA Technical Reports Server (NTRS)

Nagel, S. R.

1983-01-01

The Columbia has completed a spectacularly successful four flight Orbital Flight Test program as well as the first operational mission in which two satellites were deployed. It is unprecedented that a vehicle so complex as the Shuttle could have reached such a state of maturity in so few missions. This maturity is reflected not only in terms of basic performance during dynamic flight phases, but also in the outstanding performance of individual spacecraft systems. Appreciably more CSS time has been logged during entry and particularly in the approach and landing phase than any other segment of the mission profile. The discussion that follows, therefore, will outline this phase in some detail including pilot comments, techniques, crew displays and landing aids. Some problem areas related to landing the Orbiter will be discussed, as well as possible solutions.

Simulating flight boundary conditions for orbiter payload modal survey

NASA Technical Reports Server (NTRS)

Chung, Y. T.; Sernaker, M. L.; Peebles, J. H.

1993-01-01

An approach to simulate the characteristics of the payload/orbiter interfaces for the payload modal survey was developed. The flexure designed for this approach is required to provide adequate stiffness separation in the free and constrained interface degrees of freedom to closely resemble the flight boundary condition. Payloads will behave linearly and demonstrate similar modal effective mass distribution and load path as the flight if the flexure fixture is used for the payload modal survey. The potential non-linearities caused by the trunnion slippage during the conventional fixed base modal survey may be eliminated. Consequently, the effort to correlate the test and analysis models can be significantly reduced. An example is given to illustrate the selection and the sensitivity of the flexure stiffness. The advantages of using flexure fixtures for the modal survey and for the analytical model verification are also demonstrated.

Upgrades to Electronic Speckle Interferometer (ESPI) Operation and Data Analysis at NASA's Goddard Space Flight Center

NASA Technical Reports Server (NTRS)

Connelly, Joseph; Blake, Peter; Jones, Joycelyn

2008-01-01

The authors report operational upgrades and streamlined data analysis of a commissioned electronic speckle interferometer (ESPI) in a permanent in-house facility at NASA's Goddard Space Flight Center. Our ESPI was commercially purchased for use by the James Webb Space Telescope (JWST) development team. We have quantified and reduced systematic error sources, improved the software operability with a user-friendly graphic interface, developed an instrument simulator, streamlined data analysis for long-duration testing, and implemented a turn-key approach to speckle interferometry. We also summarize results from a test of the JWST support structure (previously published), and present new results from several pieces of test hardware at various environmental conditions.

Knowledge-based system for flight information management. Thesis

NASA Technical Reports Server (NTRS)

Ricks, Wendell R.

1990-01-01

The use of knowledge-based system (KBS) architectures to manage information on the primary flight display (PFD) of commercial aircraft is described. The PFD information management strategy used tailored the information on the PFD to the tasks the pilot performed. The KBS design and implementation of the task-tailored PFD information management application is described. The knowledge acquisition and subsequent system design of a flight-phase-detection KBS is also described. The flight-phase output of this KBS was used as input to the task-tailored PFD information management KBS. The implementation and integration of this KBS with existing aircraft systems and the other KBS is described. The flight tests are examined of both KBS's, collectively called the Task-Tailored Flight Information Manager (TTFIM), which verified their implementation and integration, and validated the software engineering advantages of the KBS approach in an operational environment.

A tactual display aid for primary flight training

NASA Technical Reports Server (NTRS)

Gilson, R. D.

1979-01-01

A means of flight instruction is discussed. In addition to verbal assistance, control feedback was continously presented via a nonvisual means utilizing touch. A kinesthetic-tactile (KT) display was used as a readout and tracking device for a computer generated signal of desired angle of attack during the approach and landing. Airspeed and glide path information was presented via KT or visual heads up display techniques. Performance with the heads up display of pitch information was shown to be significantly better than performance with the KT pitch display. Testing without the displays showed that novice pilots who had received tactile pitch error information performed both pitch and throttle control tasks significantly better than those who had received the same information from the visual heads up display of pitch during the test series of approaches to landing.

Reduced Uncertainties in the Flutter Analysis of the Aerostructures Test Wing

NASA Technical Reports Server (NTRS)

Pak, Chan-gi; Lung, Shun-fat

2010-01-01

Tuning the finite element model using measured data to minimize the model uncertainties is a challenging task in the area of structural dynamics. A test validated finite element model can provide a reliable flutter analysis to define the flutter placard speed to which the aircraft can be flown prior to flight flutter testing. Minimizing the difference between numerical and experimental results is a type of optimization problem. Through the use of the National Aeronautics and Space Administration Dryden Flight Research Center s (Edwards, California, USA) multidisciplinary design, analysis, and optimization tool to optimize the objective function and constraints; the mass properties, the natural frequencies, and the mode shapes are matched to the target data and the mass matrix orthogonality is retained. The approach in this study has been applied to minimize the model uncertainties for the structural dynamic model of the aerostructures test wing, which was designed, built, and tested at the National Aeronautics and Space Administration Dryden Flight Research Center. A 25-percent change in flutter speed has been shown after reducing the uncertainties

Reduced Uncertainties in the Flutter Analysis of the Aerostructures Test Wing

NASA Technical Reports Server (NTRS)

Pak, Chan-Gi; Lung, Shun Fat

2011-01-01

Tuning the finite element model using measured data to minimize the model uncertainties is a challenging task in the area of structural dynamics. A test validated finite element model can provide a reliable flutter analysis to define the flutter placard speed to which the aircraft can be flown prior to flight flutter testing. Minimizing the difference between numerical and experimental results is a type of optimization problem. Through the use of the National Aeronautics and Space Administration Dryden Flight Research Center's (Edwards, California) multidisciplinary design, analysis, and optimization tool to optimize the objective function and constraints; the mass properties, the natural frequencies, and the mode shapes are matched to the target data, and the mass matrix orthogonality is retained. The approach in this study has been applied to minimize the model uncertainties for the structural dynamic model of the aerostructures test wing, which was designed, built, and tested at the National Aeronautics and Space Administration Dryden Flight Research Center. A 25 percent change in flutter speed has been shown after reducing the uncertainties.

Family System of Advanced Charring Ablators for Planetary Exploration Missions

NASA Technical Reports Server (NTRS)

Congdon, William M.; Curry, Donald M.

2005-01-01

Advanced Ablators Program Objectives: 1) Flight-ready(TRL-6) ablative heat shields for deep-space missions; 2) Diversity of selection from family-system approach; 3) Minimum weight systems with high reliability; 4) Optimized formulations and processing; 5) Fully characterized properties; and 6) Low-cost manufacturing. Definition and integration of candidate lightweight structures. Test and analysis database to support flight-vehicle engineering. Results from production scale-up studies and production-cost analyses.

Quasi-steady aerodynamic model of clap-and-fling flapping MAV and validation using free-flight data.

PubMed

Armanini, S F; Caetano, J V; Croon, G C H E de; Visser, C C de; Mulder, M

2016-06-30

Flapping-wing aerodynamic models that are accurate, computationally efficient and physically meaningful, are challenging to obtain. Such models are essential to design flapping-wing micro air vehicles and to develop advanced controllers enhancing the autonomy of such vehicles. In this work, a phenomenological model is developed for the time-resolved aerodynamic forces on clap-and-fling ornithopters. The model is based on quasi-steady theory and accounts for inertial, circulatory, added mass and viscous forces. It extends existing quasi-steady approaches by: including a fling circulation factor to account for unsteady wing-wing interaction, considering real platform-specific wing kinematics and different flight regimes. The model parameters are estimated from wind tunnel measurements conducted on a real test platform. Comparison to wind tunnel data shows that the model predicts the lift forces on the test platform accurately, and accounts for wing-wing interaction effectively. Additionally, validation tests with real free-flight data show that lift forces can be predicted with considerable accuracy in different flight regimes. The complete parameter-varying model represents a wide range of flight conditions, is computationally simple, physically meaningful and requires few measurements. It is therefore potentially useful for both control design and preliminary conceptual studies for developing new platforms.

Flight assessment of the onboard propulsion system model for the Performance Seeking Control algorithm on an F-15 aircraft

NASA Technical Reports Server (NTRS)

Orme, John S.; Schkolnik, Gerard S.

1995-01-01

Performance Seeking Control (PSC), an onboard, adaptive, real-time optimization algorithm, relies upon an onboard propulsion system model. Flight results illustrated propulsion system performance improvements as calculated by the model. These improvements were subject to uncertainty arising from modeling error. Thus to quantify uncertainty in the PSC performance improvements, modeling accuracy must be assessed. A flight test approach to verify PSC-predicted increases in thrust (FNP) and absolute levels of fan stall margin is developed and applied to flight test data. Application of the excess thrust technique shows that increases of FNP agree to within 3 percent of full-scale measurements for most conditions. Accuracy to these levels is significant because uncertainty bands may now be applied to the performance improvements provided by PSC. Assessment of PSC fan stall margin modeling accuracy was completed with analysis of in-flight stall tests. Results indicate that the model overestimates the stall margin by between 5 to 10 percent. Because PSC achieves performance gains by using available stall margin, this overestimation may represent performance improvements to be recovered with increased modeling accuracy. Assessment of thrust and stall margin modeling accuracy provides a critical piece for a comprehensive understanding of PSC's capabilities and limitations.

An analytic modeling and system identification study of rotor/fuselage dynamics at hover

NASA Technical Reports Server (NTRS)

Hong, Steven W.; Curtiss, H. C., Jr.

1993-01-01

A combination of analytic modeling and system identification methods have been used to develop an improved dynamic model describing the response of articulated rotor helicopters to control inputs. A high-order linearized model of coupled rotor/body dynamics including flap and lag degrees of freedom and inflow dynamics with literal coefficients is compared to flight test data from single rotor helicopters in the near hover trim condition. The identification problem was formulated using the maximum likelihood function in the time domain. The dynamic model with literal coefficients was used to generate the model states, and the model was parametrized in terms of physical constants of the aircraft rather than the stability derivatives resulting in a significant reduction in the number of quantities to be identified. The likelihood function was optimized using the genetic algorithm approach. This method proved highly effective in producing an estimated model from flight test data which included coupled fuselage/rotor dynamics. Using this approach it has been shown that blade flexibility is a significant contributing factor to the discrepancies between theory and experiment shown in previous studies. Addition of flexible modes, properly incorporating the constraint due to the lag dampers, results in excellent agreement between flight test and theory, especially in the high frequency range.

An analytic modeling and system identification study of rotor/fuselage dynamics at hover

NASA Technical Reports Server (NTRS)

Hong, Steven W.; Curtiss, H. C., Jr.

1993-01-01

A combination of analytic modeling and system identification methods have been used to develop an improved dynamic model describing the response of articulated rotor helicopters to control inputs. A high-order linearized model of coupled rotor/body dynamics including flap and lag degrees of freedom and inflow dynamics with literal coefficients is compared to flight test data from single rotor helicopters in the near hover trim condition. The identification problem was formulated using the maximum likelihood function in the time domain. The dynamic model with literal coefficients was used to generate the model states, and the model was parametrized in terms of physical constants of the aircraft rather than the stability derivatives, resulting in a significant reduction in the number of quantities to be identified. The likelihood function was optimized using the genetic algorithm approach. This method proved highly effective in producing an estimated model from flight test data which included coupled fuselage/rotor dynamics. Using this approach it has been shown that blade flexibility is a significant contributing factor to the discrepancies between theory and experiment shown in previous studies. Addition of flexible modes, properly incorporating the constraint due to the lag dampers, results in excellent agreement between flight test and theory, especially in the high frequency range.

Modeling methods for high-fidelity rotorcraft flight mechanics simulation

NASA Technical Reports Server (NTRS)

Mansur, M. Hossein; Tischler, Mark B.; Chaimovich, Menahem; Rosen, Aviv; Rand, Omri

1992-01-01

The cooperative effort being carried out under the agreements of the United States-Israel Memorandum of Understanding is discussed. Two different models of the AH-64 Apache Helicopter, which may differ in their approach to modeling the main rotor, are presented. The first model, the Blade Element Model for the Apache (BEMAP), was developed at Ames Research Center, and is the only model of the Apache to employ a direct blade element approach to calculating the coupled flap-lag motion of the blades and the rotor force and moment. The second model was developed at the Technion-Israel Institute of Technology and uses an harmonic approach to analyze the rotor. The approach allows two different levels of approximation, ranging from the 'first harmonic' (similar to a tip-path-plane model) to 'complete high harmonics' (comparable to a blade element approach). The development of the two models is outlined and the two are compared using available flight test data.

Large space structures controls research and development at Marshall Space Flight Center: Status and future plans

NASA Technical Reports Server (NTRS)

Buchanan, H. J.

1983-01-01

Work performed in Large Space Structures Controls research and development program at Marshall Space Flight Center is described. Studies to develop a multilevel control approach which supports a modular or building block approach to the buildup of space platforms are discussed. A concept has been developed and tested in three-axis computer simulation utilizing a five-body model of a basic space platform module. Analytical efforts have continued to focus on extension of the basic theory and subsequent application. Consideration is also given to specifications to evaluate several algorithms for controlling the shape of Large Space Structures.