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1

Aircraft Speed Instruments  

NASA Technical Reports Server (NTRS)

This report presents a concise survey of the measurement of air speed and ground speed on board aircraft. Special attention is paid to the pitot-static air-speed meter which is the standard in the United States for airplanes. Air-speed meters of the rotating vane type are also discussed in considerable detail on account of their value as flight test instruments and as service instruments for airships. Methods of ground-speed measurement are treated briefly, with reference to the more important instruments. A bibliography on air-speed measurement concludes the report.

Beij, K Hilding

1933-01-01

2

Alaskan flight trials of a synthetic vision system for instrument landings of a piston twin aircraft  

Microsoft Academic Search

Stanford University has developed a low-cost prototype synthetic vision system and flight tested it onboard general aviation aircraft. The display aids pilots by providing an 'out the window' view, making visualization of the desired flight path a simple task. Predictor symbology provides guidance on straight and curved paths presented in a 'tunnel- in-the-sky' format. Based on commodity PC hardware to

Andrew K. Barrows; Keith W. Alter; Chad W. Jennings; J. D. Powell

1999-01-01

3

Pathfinder Aircraft in Flight  

NASA Technical Reports Server (NTRS)

The Pathfinder research aircraft's wing structure was clearly defined as it soared under a clear blue sky during a test flight July 27, 1995, from Dryden Flight Research Center, Edwards, California. The center section and outer wing panels of the aircraft had ribs constructed of thin plastic foam, while the ribs in the inner wing panels are fabricated from lightweight composite material. Developed by AeroVironment, Inc., the Pathfinder was one of several unmanned aircraft being evaluated under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) program. Pathfinder was a lightweight, solar-powered, remotely piloted flying wing aircraft used to demonstrate the use of solar power for long- duration, high-altitude flight. Its name denotes its mission as the 'Pathfinder' or first in a series of solar-powered aircraft that will be able to remain airborne for weeks or months on scientific sampling and imaging missions. Solar arrays covered most of the upper wing surface of the Pathfinder aircraft. These arrays provided up to 8,000 watts of power at high noon on a clear summer day. That power fed the aircraft's six electric motors as well as its avionics, communications, and other electrical systems. Pathfinder also had a backup battery system that could provide power for two to five hours, allowing for limited-duration flight after dark. Pathfinder flew at airspeeds of only 15 to 20 mph. Pitch control was maintained by using tiny elevators on the trailing edge of the wing while turns and yaw control were accomplished by slowing down or speeding up the motors on the outboard sections of the wing. On September 11, 1995, Pathfinder set a new altitude record for solar- powered aircraft of 50,567 feet above Edwards Air Force Base, California, on a 12-hour flight. On July 7, 1997, it set another, unofficial record of 71,500 feet at the Pacific Missile Range Facility, Kauai, Hawaii. In 1998, Pathfinder was modified into the longer-winged Pathfinder Plus configuration.

1995-01-01

4

An Instrumentation System Applied to Formation Flight  

Microsoft Academic Search

As part of a NASA dryden autonomous formation flight program for improved drag reduction of multiple F\\/A-18 aircraft, a new instrument, the formation flight instrumentation system (FFIS), for the precise estimation of the relative position, velocity, and attitude between two moving aircraft without the aid of ground-based instruments, was developed. The FFIS uses a global position system (GPS) receiver and

Walton R. Williamson; Mamoun F. Abdel-Hafez; Ihnseok Rhee; Eun-Jung Song; Jonathan D. Wolfe; David F. Chichka; Jason L. Speyer

2007-01-01

5

ASDAR (aircraft to satellite data relay) flight test report  

NASA Technical Reports Server (NTRS)

The aircraft to Satellite Data Relay (ASDAR), an airborne data collection system that gathers meteorological data from existing aircraft instrumentation and relays it to ground user via a geo-synchronous meteorological satellite, is described and the results of the first test flight on a commercial Boeing 747 aircraft are presented. The flight test was successful and verified system performance in the anticipated environment.

Domino, E. J.; Lovell, R. R.; Conroy, M. J.; Culp, D. H.

1977-01-01

6

Aeronautic Instruments. Section III : Aircraft Speed Instruments  

NASA Technical Reports Server (NTRS)

Part 1 contains a discussion and description of the various types of air speed measuring instruments. The authors then give general specifications and performance requirements with the results of tests on air speed indicators at the Bureau of Standards. Part 2 reports methods and laboratory apparatus used at the Bureau of Standards to make static tests. Methods are also given of combining wind tunnel tests with static tests. Consideration is also given to free flight tests. Part 3 discusses the problem of finding suitable methods for the purpose of measuring the speed of aircraft relative to the ground.

Hunt, Franklin L; Stearns, H O

1923-01-01

7

14 CFR 135.338 - Qualifications: Flight instructors (aircraft) and flight instructors (simulator).  

Code of Federal Regulations, 2014 CFR

...Qualifications: Flight instructors (aircraft) and flight instructors (simulator...RULES GOVERNING PERSONS ON BOARD SUCH AIRCRAFT Training § 135.338 Qualifications: Flight instructors (aircraft) and flight instructors...

2014-01-01

8

14 CFR 135.338 - Qualifications: Flight instructors (aircraft) and flight instructors (simulator).  

Code of Federal Regulations, 2011 CFR

...Qualifications: Flight instructors (aircraft) and flight instructors (simulator...RULES GOVERNING PERSONS ON BOARD SUCH AIRCRAFT Training § 135.338 Qualifications: Flight instructors (aircraft) and flight instructors...

2011-01-01

9

14 CFR 135.338 - Qualifications: Flight instructors (aircraft) and flight instructors (simulator).  

Code of Federal Regulations, 2012 CFR

...Qualifications: Flight instructors (aircraft) and flight instructors (simulator...RULES GOVERNING PERSONS ON BOARD SUCH AIRCRAFT Training § 135.338 Qualifications: Flight instructors (aircraft) and flight instructors...

2012-01-01

10

14 CFR 135.338 - Qualifications: Flight instructors (aircraft) and flight instructors (simulator).  

Code of Federal Regulations, 2010 CFR

...Qualifications: Flight instructors (aircraft) and flight instructors (simulator...RULES GOVERNING PERSONS ON BOARD SUCH AIRCRAFT Training § 135.338 Qualifications: Flight instructors (aircraft) and flight instructors...

2010-01-01

11

14 CFR 135.338 - Qualifications: Flight instructors (aircraft) and flight instructors (simulator).  

Code of Federal Regulations, 2013 CFR

...Qualifications: Flight instructors (aircraft) and flight instructors (simulator...RULES GOVERNING PERSONS ON BOARD SUCH AIRCRAFT Training § 135.338 Qualifications: Flight instructors (aircraft) and flight instructors...

2013-01-01

12

Flight directors for STOl aircraft  

NASA Technical Reports Server (NTRS)

Flight director logic for flight path and airspeed control of a powered-lift STOL aircraft in the approach, transition, and landing configurations are developed. The methods for flight director design are investigated. The first method is based on the Optimal Control Model (OCM) of the pilot. The second method, proposed here, uses a fixed dynamic model of the pilot in a state space formulation similar to that of the OCM, and includes a pilot work-load metric. Several design examples are presented with various aircraft, sensor, and control configurations. These examples show the strong impact of throttle effectiveness on the performance and pilot work-load associated with manual control of powered-lift aircraft during approach. Improved performed and reduced pilot work-load can be achieved by using direct-lift-control to increase throttle effectiveness.

Rabin, U. H.

1983-01-01

13

Laser Powered Aircraft Takes Flight  

NASA Technical Reports Server (NTRS)

A team of NASA researchers from Marshall Space Flight Center (MSFC) and Dryden Flight Research center have proven that beamed light can be used to power an aircraft, a first-in-the-world accomplishment to the best of their knowledge. Using an experimental custom built radio-controlled model aircraft, the team has demonstrated a system that beams enough light energy from the ground to power the propeller of an aircraft and sustain it in flight. Special photovoltaic arrays on the plane, similar to solar cells, receive the light energy and convert it to electric current to drive the propeller motor. In a series of indoor flights this week at MSFC, a lightweight custom built laser beam was aimed at the airplane `s solar panels. The laser tracks the plane, maintaining power on its cells until the end of the flight when the laser is turned off and the airplane glides to a landing. The laser source demonstration represents the capability to beam more power to a plane so that it can reach higher altitudes and have a greater flight range without having to carry fuel or batteries, enabling an indefinite flight time. The demonstration was a collaborative effort between the Dryden Center at Edward's, California, where the aircraft was designed and built, and MSFC, where integration and testing of the laser and photovoltaic cells was done. Laser power beaming is a promising technology for consideration in new aircraft design and operation, and supports NASA's goals in the development of revolutionary aerospace technologies. Photographed with their invention are (from left to right): David Bushman and Tony Frackowiak, both of Dryden; and MSFC's Robert Burdine.

2003-01-01

14

Unmanned reconnaissance aircraft, Predator B in flight.  

NASA Technical Reports Server (NTRS)

Predator B unmanned reconnaissance aircraft, shown here, under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) project. ALTAIR/PREDATOR B -- General Atomics Aeronautical Systems, Inc., is developing the Altair version of its Predator B unmanned reconnaissance aircraft, shown here, under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) project. NASA plans to use the Altair as a technology demonstrator testbed aircraft to validate a variety of command and control technologies for unmanned aerial vehicles (UAV), as well as demonstrate the capability to perform a variety of Earth science missions. The Altair is designed to carry an 700-lb. payload of scientific instruments and imaging equipment for as long as 32 hours at up to 52,000 feet altitude. Ten-foot extensions have been added to each wing, giving the Altair an overall wingspan of 84 feet with an aspect ratio of 23. It is powered by a 700-hp. rear-mounted TPE-331-10 turboprop engine, driving a three-blade propeller. Altair is scheduled to begin flight tests in the fourth quarter of 2002, and be acquired by NASA following successful completion of those basic airworthiness tests in early 2003 for evaluation of over-the-horizon control, detect, see and avoid and other technologies required to allow UAVs to operate safely with other aircraft in the national airspace.

2001-01-01

15

Analysis of wind profile measurements from an instrumented aircraft  

NASA Technical Reports Server (NTRS)

The results of an experimental program to determine the capability of measuring wind profiles on support of STS operations with an instrumented aircraft are discussed. These results are a compilation of the flight experiments and the statistical data comparing the quality of the aircraft measurements with quasi-simultaneous and quasi-spatial overlapping Jimsphere measurements. An instrumented aircraft was chosen as a potential alternative to the Jimsphere/radar system for expediting the wind profile calculation by virtue of the ability of an aircraft to traverse the altitudes of interest in roughly 10 minutes. The two aircraft which participated in the study were F-104 and ER-2.

Paige, Terry S.; Murphy, Patrick J.

1990-01-01

16

Aircraft icing instrumentation: Unfilled needs. [rotary wing aircraft  

NASA Technical Reports Server (NTRS)

A list of icing instrumentation requirements are presented. Because of the Army's helicopter orientation, many of the suggestions are specific to rotary wing aircraft; however, some of the instrumentation are also suitable for general aviation aircraft.

Kitchens, P. F.

1980-01-01

17

PIK-20 Aircraft in Flight  

NASA Technical Reports Server (NTRS)

This photo shows NASA's PIK-20E motor-glider sailplane during a research flight from the Ames-Dryden Flight Research Facility (later, the Dryden Flight Research Center), Edwards, California, in 1991. The PIK-20E was a sailplane flown at NASA's Ames-Dryden Flight Research Facility (now Dryden Flight Research Center, Edwards, California) beginning in 1981. The vehicle, bearing NASA tail number 803, was used as a research vehicle on projects calling for high lift-over-drag and low-speed performance. Later NASA used the PIK-20E to study the flow of fluids over the aircraft's surface at various speeds and angles of attack as part of a study of airflow efficiency over lifting surfaces. The single-seat aircraft was used to begin developing procedures for collecting sailplane glide performance data in a program carried out by Ames-Dryden. It was also used to study high-lift aerodynamics and laminar flow on high-lift airfoils. Built by Eiri-Avion in Finland, the PIK-20E is a sailplane with a two-cylinder 43-horsepower, retractable engine. It is made of carbon fiber with sandwich construction. In this unique configuration, it takes off and climbs to altitude on its own. After reaching the desired altitude, the engine is shut down and folded back into the fuselage and the aircraft is then operated as a conventional sailplane. Construction of the PIK-20E series was rather unusual. The factory used high-temperature epoxies cured in an autoclave, making the structure resistant to deformation with age. Unlike today's normal practice of laying glass over gelcoat in a mold, the PIK-20E was built without gelcoat. The finish is the result of smooth glass lay-up, a small amount of filler, and an acrylic enamel paint. The sailplane was 21.4 feet long and had a wingspan of 49.2 feet. It featured a wooden, fixed-pitch propeller, a roomy cockpit, wingtip wheels, and a steerable tailwheel.

1991-01-01

18

Outsider's look at flight instrumentation  

SciTech Connect

This paper presents ideas and speculations on possible diagnostic instrumentation for use in missile flight testing. A plea is made for increased instrumentation efforts. There is some discussion of telemetry methods.

Lundy, A.S.

1981-01-01

19

Development of flight instrumentation and analysis of an aircraft's lateral response to a discrete two-dimensional vertical gust  

E-print Network

conditions there were directional control problems created by the adverse yaw rate and yaw angle which doubled with maximum f'lap deflection. This decrease in directional stability for the high lift landing configuration indicates that the pilot... of the flight investigation shoved that the maximum adverse yaw rate, creat?d by an a11?ron st?p input, increased from 0 deg/sec iv to 10 deg/sec while the maximum sideslip angle decreased from i5 degrees tc 5 degrees by increasing the flap deflection to its...

Mask, Russell Lane

2012-06-07

20

Bird flight and airplane flight. [instruments to measure air currents and flight characteristics  

NASA Technical Reports Server (NTRS)

Research was based on a series of mechanical, electrical, and cinematographic instruments developed to measure various features of air current behavior as well as bird and airplane flight. Investigation of rising obstruction and thermal currents led to a theory of bird flight, especially of the gliding and soaring types. It was shown how a knowledge of bird flight can be applied to glider and ultimately motorized aircraft construction. The instruments and methods used in studying stress in airplanes and in comparing the lift to drag ratios of airplanes and birds are described.

Magnan, A.

1980-01-01

21

Development and evaluation of a prototype in-flight instrument flight rules (IFR) procedures trainer  

NASA Technical Reports Server (NTRS)

An in-flight instrument flight rules (IFR) procedures trainer capable of providing simulated indications of instrument flight in a typical general aviation aircraft independent of ground based navigation aids was developed. The IFR navaid related instruments and circuits from an ATC 610J table top simulator were installed in a Cessna 172 aircraft and connected to its electrical power and pitot static systems. The benefits expected from this hybridization concept include increased safety by reducing the number of general aviation aircraft conducting IFR training flights in congested terminal areas, and reduced fuel use and instruction costs by lessening the need to fly to and from navaid equipped airports and by increased efficiency of the required in-flight training. Technical feasibility was demonstrated and the operational feasibility of the concept was evaluated. Results indicated that the in-flight simulator is an effective training device for teaching IFR procedural skills.

Aaron, J. B., Jr.; Morris, G. G.

1981-01-01

22

Aircraft Power-Plant Instruments  

NASA Technical Reports Server (NTRS)

This report supersedes NACA-TR-129 which is now obsolete. Aircraft power-plant instruments include tachometers, engine thermometers, pressure gages, fuel-quantity gages, fuel flow meters and indicators, and manifold pressure gages. The report includes a description of the commonly used types and some others, the underlying principle utilized in the design, and some design data. The inherent errors of the instrument, the methods of making laboratory tests, descriptions of the test apparatus, and data in considerable detail in the performance of commonly used instruments are presented. Standard instruments and, in cases where it appears to be of interest, those used as secondary standards are described. A bibliography of important articles is included.

Sontag, Harcourt; Brombacher, W G

1934-01-01

23

Instrumentation for Unmanned Aircraft Systems (UAS)  

E-print Network

Instrumentation for Unmanned Aircraft Systems (UAS) David Delene Department of Atmospheric Sciences Aircraft September 2, 2012 Cloud Deck from Citation Research Aircraft August 30, 2012 #12;Impact Zero Filter #12;Passive Cavity Aerosol Spectrometer Probe on Citation Research Aircraft on July 31

Delene, David J.

24

Aircraft Engine Performance Study Using Flight Data Recorder Archives  

E-print Network

Aircraft Engine Performance Study Using Flight Data Recorder Archives Yashovardhan S. Chati and Hamsa Balakrishnan Massachusetts Institute of Technology, Cambridge, Massachusetts, 02139, USA Aircraft Flight Data Recorder (FDR) is an accurate source of information as it logs operational aircraft data

Gummadi, Ramakrishna

25

Statistical Detection of Atypical Aircraft Flights  

NASA Technical Reports Server (NTRS)

A computational method and software to implement the method have been developed to sift through vast quantities of digital flight data to alert human analysts to aircraft flights that are statistically atypical in ways that signify that safety may be adversely affected. On a typical day, there are tens of thousands of flights in the United States and several times that number throughout the world. Depending on the specific aircraft design, the volume of data collected by sensors and flight recorders can range from a few dozen to several thousand parameters per second during a flight. Whereas these data have long been utilized in investigating crashes, the present method is oriented toward helping to prevent crashes by enabling routine monitoring of flight operations to identify portions of flights that may be of interest with respect to safety issues.

Statler, Irving; Chidester, Thomas; Shafto, Michael; Ferryman, Thomas; Amidan, Brett; Whitney, Paul; White, Amanda; Willse, Alan; Cooley, Scott; Jay, Joseph; Rosenthal, Loren; Swickard, Andrea; Bates, Derrick; Scherrer, Chad; Webb, Bobbie-Jo; Lawrence, Robert; Mosbrucker, Chris; Prothero, Gary; Andrei, Adi; Romanowski, Tim; Robin, Daniel; Prothero, Jason; Lynch, Robert; Lowe, Michael

2006-01-01

26

Comprehensive analysis of transport aircraft flight performance  

NASA Astrophysics Data System (ADS)

This paper reviews the state-of-the art in comprehensive performance codes for fixed-wing aircraft. The importance of system analysis in flight performance is discussed. The paper highlights the role of aerodynamics, propulsion, flight mechanics, aeroacoustics, flight operation, numerical optimisation, stochastic methods and numerical analysis. The latter discipline is used to investigate the sensitivities of the sub-systems to uncertainties in critical state parameters or functional parameters. The paper discusses critically the data used for performance analysis, and the areas where progress is required. Comprehensive analysis codes can be used for mission fuel planning, envelope exploration, competition analysis, a wide variety of environmental studies, marketing analysis, aircraft certification and conceptual aircraft design. A comprehensive program that uses the multi-disciplinary approach for transport aircraft is presented. The model includes a geometry deck, a separate engine input deck with the main parameters, a database of engine performance from an independent simulation, and an operational deck. The comprehensive code has modules for deriving the geometry from bitmap files, an aerodynamics model for all flight conditions, a flight mechanics model for flight envelopes and mission analysis, an aircraft noise model and engine emissions. The model is validated at different levels. Validation of the aerodynamic model is done against the scale models DLR-F4 and F6. A general model analysis and flight envelope exploration are shown for the Boeing B-777-300 with GE-90 turbofan engines with intermediate passenger capacity (394 passengers in 2 classes). Validation of the flight model is done by sensitivity analysis on the wetted area (or profile drag), on the specific air range, the brake-release gross weight and the aircraft noise. A variety of results is shown, including specific air range charts, take-off weight-altitude charts, payload-range performance, atmospheric effects, economic Mach number and noise trajectories at F.A.R. landing points.

Filippone, Antonio

2008-04-01

27

Flight recorders and aircraft safety  

Microsoft Academic Search

This paper discusses flight recorders, particularly the digital flight data recorder. It includes an illustration of how this device provided data to National Transportation Safety Board investigators which, for the first time, proved that wind shear was a primary factor in an air carrier accident. It also discusses the need for technological development in the area of flight recorder systems,

Carol A. Roberts

1976-01-01

28

Digital signal conditioning for flight test instrumentation  

NASA Technical Reports Server (NTRS)

An introduction to digital measurement processes on aircraft is provided. Flight test instrumentation systems are rapidly evolving from analog-intensive to digital intensive systems, including the use of onboard digital computers. The topics include measurements that are digital in origin, as well as sampling, encoding, transmitting, and storing data. Particular emphasis is placed on modern avionic data bus architectures and what to be aware of when extracting data from them. Examples of data extraction techniques are given. Tradeoffs between digital logic families, trends in digital development, and design testing techniques are discussed. An introduction to digital filtering is also covered.

Bever, Glenn A.

1991-01-01

29

AD-1 aircraft in flight  

NASA Technical Reports Server (NTRS)

The Ames-Dryden (AD)-1 was a research aircraft designed to investigate the concept of an oblique (or pivoting) wing. The movie clip runs about 17 seconds and has two air-to-air views of the AD-1. The first shot is from slightly above as the wing pivots to 60 degrees. The other angle is almost directly below the aircraft when the wing is fully pivoted.

1980-01-01

30

Iced Aircraft Flight Data for Flight Simulator Validation  

NASA Technical Reports Server (NTRS)

NASA is developing and validating technology to incorporate aircraft icing effects into a flight training device concept demonstrator. Flight simulation models of a DHC-6 Twin Otter were developed from wind tunnel data using a subscale, complete aircraft model with and without simulated ice, and from previously acquired flight data. The validation of the simulation models required additional aircraft response time histories of the airplane configured with simulated ice similar to the subscale model testing. Therefore, a flight test was conducted using the NASA Twin Otter Icing Research Aircraft. Over 500 maneuvers of various types were conducted in this flight test. The validation data consisted of aircraft state parameters, pilot inputs, propulsion, weight, center of gravity, and moments of inertia with the airplane configured with different amounts of simulated ice. Emphasis was made to acquire data at wing stall and tailplane stall since these events are of primary interest to model accurately in the flight training device. Analyses of several datasets are described regarding wing and tailplane stall. Key findings from these analyses are that the simulated wing ice shapes significantly reduced the C , max, while the simulated tail ice caused elevator control force anomalies and tailplane stall when flaps were deflected 30 deg or greater. This effectively reduced the safe operating margins between iced wing and iced tail stall as flap deflection and thrust were increased. This flight test demonstrated that the critical aspects to be modeled in the icing effects flight training device include: iced wing and tail stall speeds, flap and thrust effects, control forces, and control effectiveness.

Ratvasky, Thomas P.; Blankenship, Kurt; Rieke, William; Brinker, David J.

2003-01-01

31

14 CFR 91.1095 - Initial and transition training and checking: Flight instructors (aircraft), flight instructors...  

Code of Federal Regulations, 2012 CFR

...could adversely affect safety. (5) The corrective...emergency procedures in the aircraft. (7) Except for holders...class, or category aircraft to which the flight instructor...flight instructors (aircraft) must include the following— (1) The safety measures for...

2012-01-01

32

14 CFR 91.1095 - Initial and transition training and checking: Flight instructors (aircraft), flight instructors...  

Code of Federal Regulations, 2011 CFR

...could adversely affect safety. (5) The corrective...emergency procedures in the aircraft. (7) Except for holders...class, or category aircraft to which the flight instructor...flight instructors (aircraft) must include the following— (1) The safety measures for...

2011-01-01

33

14 CFR 135.340 - Initial and transition training and checking: Flight instructors (aircraft), flight instructors...  

Code of Federal Regulations, 2013 CFR

...could adversely affect safety. (5) The corrective...emergency procedures in the aircraft. (7) Except for holders...class, or category aircraft to which the flight instructor...flight instructors (aircraft) must include the following— (1) The safety measures for...

2013-01-01

34

14 CFR 91.1095 - Initial and transition training and checking: Flight instructors (aircraft), flight instructors...  

Code of Federal Regulations, 2014 CFR

...could adversely affect safety. (5) The corrective...emergency procedures in the aircraft. (7) Except for holders...class, or category aircraft to which the flight instructor...flight instructors (aircraft) must include the following— (1) The safety measures for...

2014-01-01

35

14 CFR 135.340 - Initial and transition training and checking: Flight instructors (aircraft), flight instructors...  

Code of Federal Regulations, 2014 CFR

...could adversely affect safety. (5) The corrective...emergency procedures in the aircraft. (7) Except for holders...class, or category aircraft to which the flight instructor...flight instructors (aircraft) must include the following— (1) The safety measures for...

2014-01-01

36

14 CFR 135.340 - Initial and transition training and checking: Flight instructors (aircraft), flight instructors...  

Code of Federal Regulations, 2012 CFR

...could adversely affect safety. (5) The corrective...emergency procedures in the aircraft. (7) Except for holders...class, or category aircraft to which the flight instructor...flight instructors (aircraft) must include the following— (1) The safety measures for...

2012-01-01

37

14 CFR 135.340 - Initial and transition training and checking: Flight instructors (aircraft), flight instructors...  

Code of Federal Regulations, 2011 CFR

...could adversely affect safety. (5) The corrective...emergency procedures in the aircraft. (7) Except for holders...class, or category aircraft to which the flight instructor...flight instructors (aircraft) must include the following— (1) The safety measures for...

2011-01-01

38

14 CFR 91.1095 - Initial and transition training and checking: Flight instructors (aircraft), flight instructors...  

Code of Federal Regulations, 2013 CFR

...could adversely affect safety. (5) The corrective...emergency procedures in the aircraft. (7) Except for holders...class, or category aircraft to which the flight instructor...flight instructors (aircraft) must include the following— (1) The safety measures for...

2013-01-01

39

Development of a Low-Cost Sub-Scale Aircraft for Flight Research: The FASER Project  

NASA Technical Reports Server (NTRS)

An inexpensive unmanned sub-scale aircraft was developed to conduct frequent flight test experiments for research and demonstration of advanced dynamic modeling and control design concepts. This paper describes the aircraft, flight systems, flight operations, and data compatibility including details of some practical problems encountered and the solutions found. The aircraft, named Free-flying Aircraft for Sub-scale Experimental Research, or FASER, was outfitted with high-quality instrumentation to measure aircraft inputs and states, as well as vehicle health parameters. Flight data are stored onboard, but can also be telemetered to a ground station in real time for analysis. Commercial-off-the-shelf hardware and software were used as often as possible. The flight computer is based on the PC104 platform, and runs xPC-Target software. Extensive wind tunnel testing was conducted with the same aircraft used for flight testing, and a six degree-of-freedom simulation with nonlinear aerodynamics was developed to support flight tests. Flight tests to date have been conducted to mature the flight operations, validate the instrumentation, and check the flight data for kinematic consistency. Data compatibility analysis showed that the flight data are accurate and consistent after corrections are made for estimated systematic instrumentation errors.

Owens, Donald B.; Cox, David E.; Morelli, Eugene A.

2006-01-01

40

Real Time Correction of Aircraft Flight Fonfiguration  

NASA Technical Reports Server (NTRS)

Method and system for monitoring and analyzing, in real time, variation with time of an aircraft flight parameter. A time-dependent recovery band, defined by first and second recovery band boundaries that are spaced apart at at least one time point, is constructed for a selected flight parameter and for a selected time recovery time interval length .DELTA.t(FP;rec). A flight parameter, having a value FP(t=t.sub.p) at a time t=t.sub.p, is likely to be able to recover to a reference flight parameter value FP(t';ref), lying in a band of reference flight parameter values FP(t';ref;CB), within a time interval given by t.sub.p.ltoreq.t'.ltoreq.t.sub.p.DELTA.t(FP;rec), if (or only if) the flight parameter value lies between the first and second recovery band boundary traces.

Schipper, John F. (Inventor)

2009-01-01

41

Flight Safety Aircraft Risk: A Growing Problem  

NASA Astrophysics Data System (ADS)

In recent years there has been a growing awareness of the need to have appropriate criteria for protection of aircraft from debris resulting from the flight termination of a malfunctioning space booster. There have been several sequences of events that have interacted to bring us to the current risk management problem. With the advent of the US initiative to have common flight safety analysis processes and criteria, it was recognized that the traditional aircraft protection approach was inadequate. It did not consider the added public concern for catastrophic events. While the probability may have been small for downing a large commercial passenger plane, the public outrage if it happened would not be adequately measured by the individual risk to passengers nor the collective (societal risk) presented by a single airplane. Over a period of a number of years the US has developed and evolved a criterion to address catastrophic risk protection. Beginning in the same time period, it was recognized the assertion that all debris with masses greater than one gram were lethal to aircraft was unduly conservative. Over this same period initiatives have been developed to refine aircraft vulnerability models. There were, however, two significant unconservative assumptions that were made in the early years. It was presumed that significant risk to aircraft could only occur in the launch area. In addition, aircraft risk assessments, when they were made were based on debris lists designed to protect people on the ground (typically debris with an impact kinetic energy greater than 11 ft-lb). Good debris lists for aircraft protection do not yet exist. However, it has become increasingly clear that even with partial breakup lists large regions were required from which aircraft flight would be restricted using the normal exclusion approaches. We provide a review of these events and an indication of the way forward.

Haber, J. M.

2012-01-01

42

A fuzzy logic controller for aircraft flight control  

Microsoft Academic Search

This paper describes a model of an autopilot controller based on fuzzy algorithms. The controller maneuvers an aircraft from level flight into a final-approach flight path and maintains the aircraft along the glide path until just before touchdown. To evaluate the performance and effectiveness of the model, the aircraft response to controller actions is simulated using flight simulation techniques. The

Lawrence I. Larkin

1984-01-01

43

Aircraft Integration and Flight Testing of 4STAR  

SciTech Connect

Under funding from the U.S. Dept. of Energy, in conjunction with a funded NASA 2008 ROSES proposal, with internal support from Battelle Pacific Northwest Division (PNWD), and in collaboration with NASA Ames Research Center, we successfully integrated the Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research (4STAR-Air) instrument for flight operation aboard Battelle’s G-1 aircraft and conducted a series of airborne and ground-based intensive measurement campaigns (hereafter referred to as “intensives”) for the purpose of maturing the initial 4STAR-Ground prototype to a flight-ready science-ready configuration.

Flynn, CJ; Kassianov, E; Russell, P; Redemann, J; Dunagan, S; Holben, B

2012-10-12

44

DESIGN OFA SUPERVISED FLIGHT CONTROLSYSTEM FOR AIRCRAFT RELATIVE GUIDANCE  

E-print Network

of such aircraft are more constrainedthanthose of military aircraft or UAV. In addition, safety and passengerDESIGN OFA SUPERVISED FLIGHT CONTROLSYSTEM FOR AIRCRAFT RELATIVE GUIDANCE Thieny Miquel, CENA is relieved of providing instructions to the trailing aircraft for merging behind the leading aircraft

Paris-Sud XI, Université de

45

SCIP2 flight instrumentation specification for parameter identification: User's guide  

NASA Technical Reports Server (NTRS)

SCIP2 which is a digital computer program that can be used to investigate the effects of instrumentation errors on the accuracy of aircraft stability and control derivatives identified from flight test data is presented. The program is based on the assumptions that the aircraft differential equations of motion are linear and consist of small perturbations about a quasisteady flight condition. It is also assumed that a Newton-Raphson optimization technique is used for identifying the estimates of the parameters. A summary of the equations which are coded in the program are included.

Taniguchi, N.

1972-01-01

46

Identification of flexible aircraft from flight data  

NASA Technical Reports Server (NTRS)

This paper describes a frequency-domain method for the estimation of the aeroelastic equations of motion of an aircraft using discrete sinusoidal inputs to the control surface actuators. The theory of estimation of the signal inputs and outputs is described as well as the method of obtaining accurate transfer functions from the resulting Bode plots. Methods of quantifying the accuracy of the results from more than one control input are discussed along with ways to obtain state-space and reduced-order models from the transfer function estimates. Presented is a summary of the results obtained in using the technique to develop a model of the USAF Total In-Flight Simulator (TIFS) aircraft which includes five symmetrical elastic modes of motion of the aircraft.

Eulrich, B. J.; Rynaski, E. G.

1980-01-01

47

The inverse simulation study of aircraft flight path reconstruction  

Microsoft Academic Search

This paper presents a uniform approach to the modelling and simulation of aircraft prescribed trajectory flight. The aircraft motion is specified by a trajectory in space, a condition on airframe attitude with respect to the trajectory, and a desired flight velocity variation. For an aircraft controlled by aileron, elevator and rudder deflections and thrust changes a tangent realization of trajectory

Wojciech Blajer; Jacek A. Goszczy?ski; Mariusz Krawczyk

2002-01-01

48

ERAST Program Proteus Aircraft in Flight  

NASA Technical Reports Server (NTRS)

The unusual design of the Proteus high-altitude aircraft, incorporating a gull-wing shape for its main wing and a long, slender forward canard, is clearly visible in this view of the aircraft in flight over the Mojave Desert in California. In the Proteus Project, NASA's Dryden Flight Research Center, Edwards, California, is assisting Scaled Composites, Inc., Mojave, California, in developing a sophisticated station-keeping autopilot system and a Satellite Communications (SATCOM)-based uplink-downlink data system for aircraft and payload data under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) project. The ERAST Project is sponsored by the Office of Aero-Space Technology at NASA Headquarters, and is managed by the Dryden Flight Research Center. The Proteus is a unique aircraft, designed as a high-altitude, long-duration telecommunications relay platform with potential for use on atmospheric sampling and Earth-monitoring science missions. The aircraft is designed to be flown by two pilots in a pressurized cabin, but also has the potential to perform its missions semiautonomously or be flown remotely from the ground. Flight testing of the Proteus, beginning in the summer of 1998 at Mojave Airport through the end of 1999, included the installation and checkout of the autopilot system, including the refinement of the altitude hold and altitude change software. The SATCOM equipment, including avionics and antenna systems, had been installed and checked out in several flight tests. The systems performed flawlessly during the Proteus's deployment to the Paris Airshow in 1999. NASA's ERAST project funded development of an Airborne Real-Time Imaging System (ARTIS). Developed by HyperSpectral Sciences, Inc., the small ARTIS camera was demonstrated during the summer of 1999 when it took visual and near-infrared photos over the Experimental Aircraft Association's 'AirVenture 99' Airshow at Oshkosh, Wisconsin. The images were displayed on a computer monitor at the show only moments after they were taken. This was the second successful demonstration of the ARTIS camera. The aircraft is designed to cruise at altitudes from 59,000 to more than 65,000 feet for up to 18 hours. It was designed and built by Burt Rutan, president of Scaled Composites, Inc., to carry an 18-foot diameter telecommunications antenna system for relay of broadband data over major cities. The design allows for Proteus to be reconfigured at will for a variety of other missions such as atmospheric research, reconnaissance, commercial imaging, and launch of small space satellites. It is designed for extreme reliability and low operating costs, and to operate out of general aviation airports with minimal support. The aircraft consists of an all composite airframe with graphite-epoxy sandwich construction. It has a wingspan of 77 feet 7 inches, expandable to 92 feet with removable wingtips installed. It is 56.3 feet long and 17.6 feet high and weighs 5,900 pounds, empty. Proteus is powered by two Williams-Rolls FJ44-2 turbofan engines developing 2,300 pounds of thrust each.

1999-01-01

49

Flight inspection of instrument landing system  

Microsoft Academic Search

?This paper aims to familiarize experts from other fields with issues of flight inspection of instrument landing system (ILS) and its assessment contained in the elaborated documentation. At first in chapter I. the standard volumes of the instrument landing system are described, followed by standard profiles flown during the flight inspection in chapter II. Finally, chapter III. describes the instrument

Andrej Novak; Jan Pitor

2011-01-01

50

Preliminary assessment of a supersonic STOVL flight research and demonstration aircraft  

NASA Technical Reports Server (NTRS)

NASA Ames has conducted a conceptual design study of a supersonic short takeoff and vertical landing (STOVL) flight research and demonstration aircraft sized according to current technology levels. The aircraft would provide the capability for demonstrating advanced technologies required for STOVL and would be instrumented to provide temperature, pressure, and noise data for power-induced-effects research. The propulsion concept for the single-engine aircraft studied operates in mixed flow without thrust augmentation during power-lift flight. The study aircraft is full scale to facilitate STOVL propulsion-system component validation and power-induced aerodynamics research. Performance is sufficient to permit investigation and validation of vertical landing and hover, accelerating and decelerating transitions, short takeoff, reduced-weight vertical takeoff, and supersonic flight. Mission and maneuver capability is sufficient to demonstrate the operational utility of this class of aircraft. Aircraft mission and technology sensitivities were also examined.

Samuels, Jeffrey J.; Payne, Gordon A.

1990-01-01

51

NASA Dryden Flight Research Center: Unmanned Aircraft Operations  

NASA Technical Reports Server (NTRS)

This slide presentation reviews several topics related to operating unmanned aircraft in particular sharing aspects of unmanned aircraft from the perspective of a pilot. There is a section on the Global Hawk project which contains information about the first Global Hawk science mission, (i.e., Global Hawk Pacific (GloPac). Included in this information is GloPac science highlights, a listing of the GloPac Instruments. The second Global Hawk science mission was Genesis and Rapid Intensification Process (GRIP), for the NASA Hurricane Science Research Team. Information includes the instrumentation and the flights that were undertaken during the program. A section on Ikhana is next. This section includes views of the Ground Control Station (GCS), and a discussion of how the piloting of UAS is different from piloting in a manned aircraft. There is also discussion about displays and controls of aircraft. There is also discussion about what makes a pilot. The last section relates the use of Ikhana in the western states fire mission.

Pestana, Mark

2010-01-01

52

Trimming an aircraft model for flight simulation  

NASA Technical Reports Server (NTRS)

Real-time piloted aircraft simulations with digital computers have been performed at Ames Research Center (ARC) for over two decades. For the simulation of conventional aircraft models, the establishment of initial vehicle and control orientations at various operational flight regimes has been adequately handled by either analog techniques or simple inversion processes. However, exotic helicopter configurations have been introduced recently that require more sophisticated techniques because of their expanded degrees of freedom and environmental vibration levels. At ARC, these techniques are used for the backward solutions to real-time simulation models as required for the generation of trim points. These techniques are presented in this paper with examples from a blade-element helicopter simulation model.

Mcfarland, Richard E.

1987-01-01

53

Design and flight test of the Propulsion Controlled Aircraft (PCA) flight control system on the NASA F-15 test aircraft  

NASA Technical Reports Server (NTRS)

This report describes the design, development and flight testing of the Propulsion Controlled Aircraft (PCA) flight control system performed at McDonnell Douglas Aerospace (MDA), St. Louis, Missouri and at the NASA Dryden Flight Research Facility, Edwards Air Force Base, California. This research and development program was conducted by MDA and directed by NASA through the Dryden Flight Research Facility for the period beginning January 1991 and ending December 1993. A propulsion steering backup to the aircraft conventional flight control system has been developed and flight demonstrated on a NASA F-15 test aircraft. The Propulsion Controlled Aircraft (PCA) flight system utilizes collective and differential thrust changes to steer an aircraft that experiences partial or complete failure of the hydraulically actuated control surfaces. The PCA flight control research has shown that propulsion steering is a viable backup flight control mode and can assist the pilot in safe landing recovery of a fighter aircraft that has damage to or loss of the flight control surfaces. NASA, USAF and Navy evaluation test pilots stated that the F-15 PCA design provided the control necessary to land the aircraft. Moreover, the feasibility study showed that PCA technology can be directly applied to transport aircraft and provide a major improvement in the survivability of passengers and crew of controls damaged aircraft.

Wells, Edward A.; Urnes, James M., Sr.

1994-01-01

54

Rapid Automated Aircraft Simulation Model Updating from Flight Data  

NASA Technical Reports Server (NTRS)

Techniques to identify aircraft aerodynamic characteristics from flight measurements and compute corrections to an existing simulation model of a research aircraft were investigated. The purpose of the research was to develop a process enabling rapid automated updating of aircraft simulation models using flight data and apply this capability to all flight regimes, including flight envelope extremes. The process presented has the potential to improve the efficiency of envelope expansion flight testing, revision of control system properties, and the development of high-fidelity simulators for pilot training.

Brian, Geoff; Morelli, Eugene A.

2011-01-01

55

Risk assessment of high altitude free flight commercial aircraft operations  

Microsoft Academic Search

A quantitative model is under development to assess the safety and efficiency of commercial aircraft operations under the Free Flight Program proposed for air traffic control for the US National Airspace System. The major objective of the Free Flight Program is to accommodate the dramatic growth anticipated in air traffic in the US. However, the potential impacts upon aircraft safety

C. Y. Kimura; G. M. Sandquist; D. M. Slaughter; D. L. Sanzo

1998-01-01

56

Advanced solid propellant rocket motor flight instrumentation  

NASA Astrophysics Data System (ADS)

The limitations of one propulsion contractor in interpreting flight failures using existing static and flight test data are presented. It is shown that advancements in instrumentation and data acquisition systems are needed. Test data from static and flight tests are accumulated and data histories are created to analyze trends, identify performance differences between flight and static tests, and identify deviate or anomalous performances. The usual data sampling rates of digital data acquisition system are too slow to define events leading up to failure in both static and flight tests. Existing technologies should be adapted to develop transducers new to rocket motor instrumentation. This would include the use of magnetometers, in-situ transensors, eddy current devices, microwave horns and flash X-ray. Long range instrumentation systems would be on-board televisions, delayed flight data transmission, wide angle and penetrating transducers.

Bergman, G. H.; Boyd, E. W.; Gardiner, D. S.

1981-07-01

57

Flight tests and preliminary aerodynamic parameter extraction of an externally piloted vehicle aircraft model  

NASA Technical Reports Server (NTRS)

Model aircraft flight test investigations have been undertaken to develop a low cost flight data acquisition system and to evaluate aerodynamic parameter estimation techniques. The externally piloted vehicles (EPVs) used are instrumented with sensors measuring acceleration, angular rates, angles of attack and sideslip, flight path velocity, and control deflections. Measured state variables are downlink telemetered to a ground-based real time flight data acquisition system; the data thus recorded are used by flight test engineers and EPV pilots to monitor conditions and aid in piloting tasks. Attention is given to comparisons of F-16 EPV data with wind tunnel data.

White, E. R.; Moul, M. T.; Edwards, A. C.

1985-01-01

58

Adaptive Flight Control for Aircraft Safety Enhancements  

NASA Technical Reports Server (NTRS)

This poster presents the current adaptive control research being conducted at NASA ARC and LaRC in support of the Integrated Resilient Aircraft Control (IRAC) project. The technique "Approximate Stability Margin Analysis of Hybrid Direct-Indirect Adaptive Control" has been developed at NASA ARC to address the needs for stability margin metrics for adaptive control that potentially enables future V&V of adaptive systems. The technique "Direct Adaptive Control With Unknown Actuator Failures" is developed at NASA LaRC to deal with unknown actuator failures. The technique "Adaptive Control with Adaptive Pilot Element" is being researched at NASA LaRC to investigate the effects of pilot interactions with adaptive flight control that can have implications of stability and performance.

Nguyen, Nhan T.; Gregory, Irene M.; Joshi, Suresh M.

2008-01-01

59

LED display for solo aircraft instrument navigation  

NASA Technical Reports Server (NTRS)

Solo pilot's task is made easier through convenient display of landing and navigation data. Use of display shows promise as more efficient means of presenting sequential instructions and data, such as course heading, altitude, and radio frequency, to minimize pilot's workload during solo instrument flight.

Crouch, R. K.; Kelly, W. L., VI; Lina, L. J.; Meredith, B. D.

1979-01-01

60

Instrument for Aircraft-Icing and Cloud-Physics Measurements  

NASA Technical Reports Server (NTRS)

The figure shows a compact, rugged, simple sensor head that is part of an instrumentation system for making measurements to characterize the severity of aircraft-icing conditions and/or to perform research on cloud physics. The quantities that are calculated from measurement data acquired by this system and that are used to quantify the severity of icing conditions include sizes of cloud water drops, cloud liquid water content (LWC), cloud ice water content (IWC), and cloud total water content (TWC). The sensor head is mounted on the outside of an aircraft, positioned and oriented to intercept the ambient airflow. The sensor head consists of an open housing that is heated in a controlled manner to keep it free of ice and that contains four hot-wire elements. The hot-wire sensing elements have different shapes and sizes and, therefore, exhibit different measurement efficiencies with respect to droplet size and water phase (liquid, frozen, or mixed). Three of the hot-wire sensing elements are oriented across the airflow so as to intercept incoming cloud water. For each of these elements, the LWC or TWC affects the power required to maintain a constant temperature in the presence of cloud water.

Lilie, Lyle; Bouley, Dan; Sivo, Chris

2006-01-01

61

The Small Aircraft Transportation System Higher Volume Operations (SATS HVO) Flight Experiment  

NASA Technical Reports Server (NTRS)

This paper provides a summary of conclusions from the Small Aircraft Transportation System (SATS) Higher Volume Operations (HVO) Flight Experiment which NASA conducted to determine pilot acceptability of the HVO concept for normal conditions. The SATS HVO concept improves efficiency at non-towered, non-radar airports in Instrument Meteorological Conditions (IMC) while achieving a level of safety equal to today s system. Reported are results from flight experiment data that indicate that the SATS HVO concept is viable. The success of the SATS HVO concept is based on acceptable pilot workload, performance, and subjective criteria when compared to the procedural control operations in use today at non-towered, non-radar controlled airfields in IMC. The HVO Flight Experiment, flown on NASA's Cirrus SR22, used a subset of the HVO Simulation Experiment scenarios and evaluation pilots in order to validate the simulation experiment results. HVO and Baseline (today s system) scenarios flown included: single aircraft arriving for a GPS non-precision approach; aircraft arriving for the approach with multiple traffic aircraft; and aircraft arriving for the approach with multiple traffic aircraft and then conducting a missed approach. Results reveal that all twelve low-time instrument-rated pilots preferred SATS HVO when compared to current procedural separation operations. These pilots also flew the HVO procedures safely and proficiently without additional workload in comparison to today s system (Baseline). Detailed results of pilot flight technical error, and their subjective assessments of workload and situation awareness are presented in this paper.

Williams, Daniel M.; Murdoch, Jennifer L.; Adams, Catherine H.

2005-01-01

62

Investigations of simulated aircraft flight through thunderstorm outflows  

NASA Technical Reports Server (NTRS)

The effects of wind shear on aircraft flying through thunderstorm gust fronts were investigated. A computer program was developed to solve the two dimensional, nonlinear equations of aircraft motion, including wind shear. The procedure described and documented accounts for spatial and temporal variations of the aircraft within the flow regime. Analysis of flight paths and control inputs necessary to maintain specified trajectories for aircraft having characteristics of DC-8, B-747, augmentor wing STOL, and DHC-6 aircraft was recorded. From the analysis an attempt was made to find criteria for reduction of the hazards associated with landing through thunderstorm gust fronts.

Frost, W.; Crosby, B.

1978-01-01

63

Evaluation of Contrail Reduction Strategies Based on Aircraft Flight Distances  

NASA Technical Reports Server (NTRS)

This paper evaluates a set of contrail reduction strategies based on the flight range of aircraft as contrail reduction strategies have different impacts on aircraft depending on how they plan to fly. In general, aircraft with longer flight distances cruise at the altitudes where contrails are more likely to form. The concept of the contrail frequency index is used to quantify contrail impacts. The strategy for reducing the persistent contrail formation is to minimize the contrail frequency index by altering the aircraft's cruising altitude. A user-defined factor is used to trade off between contrail reduction and extra CO2 emissions. A higher value of tradeoff factor results in more contrail reduction and extra CO2 emissions. Results show that contrail reduction strategies using various tradeo factors behave differently from short-range flights to long-range ights. Analysis shows that short-distance flights (less than 500 miles) are the most frequent flights but contribute least to contrail reduction. Therefore these aircraft have the lowest priority when applying contrail reduction strategies. Medium-distance flights (500 to 1000 miles) have a higher priority if the goal is to achieve maximum contrail reduction in total; long-distance flights (1000 to 1500 miles) have a higher priority if the goal is to achieve maximum contrail reduction per flight. The characteristics of transcontinental flights (greater than 1500 miles) vary with different weather days so the priority of applying contrail reduction strategies to the group needs to be evaluated based on the locations of the contrail areas during any given day. For the days tested, medium-distance ights contribute up to 42.6% of the reduction among the groups during a day. The contrail frequency index per 1,000 miles for medium-distance, long-distance, and transcontinental flights can be reduced by an average of 75%. The results provide a starting point for developing operational policies to reduce the impact of aviation on climate based on aircraft flight distances.

Chen, Neil Y.; Sridhar, Banavar; Li, Jinhua; Ng, Hok Kwan

2012-01-01

64

14 CFR 91.715 - Special flight authorizations for foreign civil aircraft.  

Code of Federal Regulations, 2010 CFR

...flight authorizations for foreign civil aircraft. 91.715 Section 91.715 Aeronautics...OPERATING AND FLIGHT RULES Foreign Aircraft Operations and Operations of U.S.-Registered Civil Aircraft Outside of the United States; and...

2010-01-01

65

14 CFR 91.715 - Special flight authorizations for foreign civil aircraft.  

Code of Federal Regulations, 2012 CFR

...flight authorizations for foreign civil aircraft. 91.715 Section 91.715 Aeronautics...OPERATING AND FLIGHT RULES Foreign Aircraft Operations and Operations of U.S.-Registered Civil Aircraft Outside of the United States; and...

2012-01-01

66

14 CFR 91.715 - Special flight authorizations for foreign civil aircraft.  

Code of Federal Regulations, 2013 CFR

...flight authorizations for foreign civil aircraft. 91.715 Section 91.715 Aeronautics...OPERATING AND FLIGHT RULES Foreign Aircraft Operations and Operations of U.S.-Registered Civil Aircraft Outside of the United States; and...

2013-01-01

67

14 CFR 91.715 - Special flight authorizations for foreign civil aircraft.  

Code of Federal Regulations, 2014 CFR

...flight authorizations for foreign civil aircraft. 91.715 Section 91.715 Aeronautics...OPERATING AND FLIGHT RULES Foreign Aircraft Operations and Operations of U.S.-Registered Civil Aircraft Outside of the United States; and...

2014-01-01

68

14 CFR 91.715 - Special flight authorizations for foreign civil aircraft.  

Code of Federal Regulations, 2011 CFR

...flight authorizations for foreign civil aircraft. 91.715 Section 91.715 Aeronautics...OPERATING AND FLIGHT RULES Foreign Aircraft Operations and Operations of U.S.-Registered Civil Aircraft Outside of the United States; and...

2011-01-01

69

Flight Test Safety Considerations for Airborne Science Aircraft  

NASA Technical Reports Server (NTRS)

Most of the scientific community that require scientific data or scientific measurements from aircraft do not understand the full implications of putting certain equipment on board high performance aircraft. It is the duty of the NASA Flight Operations personnel to ensure that all Principal Investigators who are given space on NASA flight research aircraft, comply with stringent safety requirements. The attitude of the experienced Flight operations personnel given this duty has been and remains one of insuring that the PI's experiment is allowed to be placed on the aircraft (facility) and can be operated in a manner that will obtain the expected data. This is sometimes a challenge. The success that NASA has in this regard is due to the fact that it is its own authority under public law, to certify its aircraft as airworthy. Airworthiness, fitness for flight, is a complex issue which pulls together all aspects of configuration management, engineering, quality, and flight safety. It is often the case at each NASA Center that is conducting airborne research, that unique solutions to some challenging safety issues are required. These solutions permit NASA to do things that would not be permitted by the Department of Transportation. This paper will use examples of various flight research configurations to show the necessity of a disciplined process leading up to flight test and mission implementation. All new configurations required engineering flight test but many, as noted in this paper, require that the modifications be flight tested to insure that they do not negatively impact on any part of the aircraft operational profiles. The success of these processes has been demonstrated over many years and NASA has accommodated experimental packages that cannot be flown on any other aircraft.

Reynolds, Randolph S.

1997-01-01

70

Aircraft design for flight below the sonic boom speed limit  

NASA Technical Reports Server (NTRS)

The avoidance of sonic booms places a constraint on aircraft design and can lead to unusual new configurations. From a comparison among several candidate designs, it is shown that an oblique-wing aircraft offers many advantages when structure, stability, flight efficiency, and airport noise are considered jointly.

Jones, R. T.

1974-01-01

71

SHEFEX II Flight Instrumentation and Preparation of Post Flight Analysis  

NASA Astrophysics Data System (ADS)

A main disadvantage of modern TPS systems for re- entry vehicles is the expensive manufacturing and maintenance process due to the complex geometry of these blunt nose configurations. To reduce the costs and to improve the aerodynamic performance the German Aerospace Center (DLR) is following a different approach using TPS structures consisting of flat ceramic tiles. To test these new sharp edged TPS structures the SHEFEX I flight experiment was designed and successfully performed by DLR in 2005. To further improve the reliability of the sharp edged TPS design at even higher Mach numbers, a second flight experiment SHEFEX II will be performed in September 2011. In comparison to SHEFEX I the second flight experiment has a fully symmetrical shape and will reach a maximum Mach number of about 11. Furthermore the vehicle has an active steering system using four canards to control the flight attitude during re-entry, e.g. roll angle, angle of attack and sideslip. After a successful flight the evaluation of the flight data will be performed using a combination of numerical and experimental tools. The data will be used for the improvement of the present numerical analysis tools and to get a better understanding of the aerothermal behaviour of sharp TPS structures. This paper presents the flight instrumentation of the SHEFEX II TPS. In addition the concept of the post flight analysis is presented.

Thiele, T.; Siebe, F.; Gülhan, A.

2011-08-01

72

Design of a MIPAS Instrument for high-altitude aircraft  

SciTech Connect

A new MIPAS (Michelson Interferometer for Passive Atmospheric Sounding) is being designed for remote sensing of atmospheric trace constituents from high-altitude aircraft. The main goal is the measurement of cross sections of stratospheric species relevant to ozone research, such as ClONO{sub 2}, N{sub 2}O{sub 5}, NO, NO{sub 2} and HNO{sub 3}. The instrument measures the mid-infrared thermal emission of the atmosphere by limb- and upward sounding. From the spectra the two-dimensional distribution of the trace species along the flight trajectory can be derived. The instrument development is based on the approved balloon-borne MIPAS-B2 and aircraft MIPAS-FT systems. The system will be located in unpressurized compartments and thus operate under ambient temperature and pressure conditions. Major design constraints are the low mass-budget (max. 200 kg) and the automated operation without personnel intervention. The paper presents the concept and current status of the instrument development. 6 refs., 7 figs., 1 tab.

Piesch, C.; Gulde, T.; Sartorius, F.F.V. [Universitae Karlsruhe (Germany)] [and others

1996-11-01

73

19 CFR 10.183 - Duty-free entry of civil aircraft, aircraft engines, ground flight simulators, parts, components...  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Duty-free entry of civil aircraft, aircraft engines, ground flight simulators, parts, components...REDUCED RATE, ETC. General Provisions Civil Aircraft § 10.183 Duty-free entry of civil...

2013-04-01

74

19 CFR 10.183 - Duty-free entry of civil aircraft, aircraft engines, ground flight simulators, parts, components...  

Code of Federal Regulations, 2012 CFR

...2012-04-01 false Duty-free entry of civil aircraft, aircraft engines, ground flight simulators, parts, components...REDUCED RATE, ETC. General Provisions Civil Aircraft § 10.183 Duty-free entry of civil...

2012-04-01

75

19 CFR 10.183 - Duty-free entry of civil aircraft, aircraft engines, ground flight simulators, parts, components...  

Code of Federal Regulations, 2011 CFR

...2011-04-01 false Duty-free entry of civil aircraft, aircraft engines, ground flight simulators, parts, components...REDUCED RATE, ETC. General Provisions Civil Aircraft § 10.183 Duty-free entry of civil...

2011-04-01

76

19 CFR 10.183 - Duty-free entry of civil aircraft, aircraft engines, ground flight simulators, parts, components...  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Duty-free entry of civil aircraft, aircraft engines, ground flight simulators, parts, components...REDUCED RATE, ETC. General Provisions Civil Aircraft § 10.183 Duty-free entry of civil...

2010-04-01

77

Risk assessment of high altitude free flight commercial aircraft operations  

SciTech Connect

A quantitative model is under development to assess the safety and efficiency of commercial aircraft operations under the Free Flight Program proposed for air traffic control for the US National Airspace System. The major objective of the Free Flight Program is to accommodate the dramatic growth anticipated in air traffic in the US. However, the potential impacts upon aircraft safety from implementing the Program have not been fully explored and evaluated. The model is directed at assessing aircraft operations at high altitude over the continental US airspace since this action is the initial step for Free Flight. Sequential steps with analysis, assessment, evaluation, and iteration will be required to satisfactorily accomplish the complete transition of US commercial aircraft traffic operations.

Kimura, C.Y.; Sandquist, G.M.; Slaughter, D.M.; Sanzo, D.L.

1998-04-23

78

Integrated Resilient Aircraft Control Project Full Scale Flight Validation  

NASA Technical Reports Server (NTRS)

Objective: Provide validation of adaptive control law concepts through full scale flight evaluation. Technical Approach: a) Engage failure mode - destabilizing or frozen surface. b) Perform formation flight and air-to-air tracking tasks. Evaluate adaptive algorithm: a) Stability metrics. b) Model following metrics. Full scale flight testing provides an ability to validate different adaptive flight control approaches. Full scale flight testing adds credence to NASA's research efforts. A sustained research effort is required to remove the road blocks and provide adaptive control as a viable design solution for increased aircraft resilience.

Bosworth, John T.

2009-01-01

79

Flight test evaluation of a method to determine the level flight performance propeller-driven aircraft  

NASA Technical Reports Server (NTRS)

A procedure is developed for deriving the level flight drag and propulsive efficiency of propeller-driven aircraft. This is a method in which the overall drag of the aircraft is expressed in terms of the measured increment of power required to overcome a corresponding known increment of drag. The aircraft is flown in unaccelerated, straight and level flight, and thus includes the effects of the propeller drag and slipstream. Propeller efficiency and airplane drag are computed on the basis of data obtained during flight test and do not rely on the analytical calculations of inadequate theory.

Cross, E. J., Jr.

1976-01-01

80

Investigation of damping liquids for aircraft instruments  

NASA Technical Reports Server (NTRS)

This report covers the results of an investigation carried on at the Bureau of Standards under a research authorization from, and with the financial assistance of, the National Advisory Committee for Aeronautics. The choice of a damping liquid for aircraft instruments is difficult owing to the range of temperature at which aircraft operate. Temperature changes affect the viscosity tremendously. The investigation was undertaken with the object of finding liquids of various viscosities otherwise suitable which had a minimum change in viscosity with temperature. The new data relate largely to solutions. The effect of temperature on the kinematic viscosity of the following liquids and solutions was determined in the temperature interval -18 degrees to +30 degrees C. (1) solutions of animal and vegetable oils in xylene. These were poppy-seed oil, two samples of neat's-foot oils, castor oil, and linseed oil. (2) solutions of mineral oil in xylene. These were Squibb's petrolatum of naphthene base and transformer oil. (3) glycerine solutions in ethyl alcohol and in mixture of 50-50 ethyl alcohol and water. (4) mixtures of normal butyl alcohol with methyl alcohol. (5) individual liquids, kerosene, mineral spirits, xylene, recoil oil. The apparatus consisted of four capillary-tube viscometers, which were immersed in a liquid bath in order to secure temperature control. The method of calibration and the related experimental data are presented.

Keulegan, G H

1929-01-01

81

Flight control simulators for unmanned fixed-wing and VTOL aircraft  

Microsoft Academic Search

Flight control simulators for fixed-wing aircraft and VTOL (Vertical Take-off and Landing) aircraft have been developed for understanding flight control dynamics and for improving control strategies and performances. They simulate automatic control of a flight path of the aircraft, using six-degree-of-freedom nonlinear equations to represent aircraft dynamics. The control system is multi-layered. For fixed-wing aircraft, it consists of flight-path controller,

Naoharu Yoshitani; Shin-ichi Hashimoto; Takehiro Kimura; Kazuki Motohashi; Shoh Ueno

2009-01-01

82

Guide to measurement of winds with instrumented aircraft  

NASA Technical Reports Server (NTRS)

Aircraft measurement techniques are reviewed. Review of past and present applications of instrument aircraft to atmospheric observations is presented. Questions to be answered relative to measuring mean wind profiles as contrasted to turbulence measurements are then addressed. Requirements of instrumentation and accuracy, data reduction, data acquisition, and theoretical and certainty analysis are considered.

Frost, Walter; Paige, Terry S.; Nelius, Andrew E.

1991-01-01

83

Introduction to the aerodynamics of flight. [including aircraft stability, and hypersonic flight  

NASA Technical Reports Server (NTRS)

General concepts of the aerodynamics of flight are discussed. Topics considered include: the atmosphere; fluid flow; subsonic flow effects; transonic flow; supersonic flow; aircraft performance; and stability and control.

Talay, T. A.

1975-01-01

84

Pathfinder-Plus aircraft in flight  

NASA Technical Reports Server (NTRS)

The Pathfinder-Plus solar-powered aircraft is shown taking off from a runway, then flying at low altitude over the ocean. The vehicle, which looks like a flying ruler, operates at low airspeed. Among the missions proposed for a solar-powered aircraft are communications relay, atmospheric studies, pipeline monitoring and gas leak detection, environmental monitoring using thermal and radar images, and disaster relief and monitoring.

1998-01-01

85

Shuttle Tile Flight Test Fixture (FTF) on NOAA WP-3D Orion aircraft  

NASA Technical Reports Server (NTRS)

This photo shows the Shuttle tile flight test fixture under the wing of a National Oceanographic and Atmospheric Administration WP-3D aircraft. A National Oceanographic and Atmospheric Administration Lockheed WP-3D made a series of flights off the eastern coast of Florida and from Edwards Air Force Base in a cooperative program with the Ames-Dryden Flight Research Facility (now the Dryden Flight Research Center, Edwards, California) in 1987 to test in-flight rain damage to the Space Shuttle thermal protection system. Dryden performed its tests with an F-104 aircraft over the facilities at Edwards, California. Both sets of tests were done at the behest of NASA's Johnson Space Center, Houston, Texas. These tests revealed that damage can occur to the Shuttle's thermal protection system during flight in rain. This is a concern, since such damage could compromise flight safety for the Space Shuttles and would certainly affect costs of operation and schedules. Sections of the Space Shuttle thermal protection system's 6- by 6-inch tiles were mounted on a pylon under the right wing of the WP-3D aircraft. The aircraft was equipped with raindropsize-measuring instruments and cloud radars. The WP-3D weather research aircraft obtained rain impact data for airspeeds between 180 and 260 knots indicated airspeed. Test samples were mounted on two movable doors contained within the left and right sides of the test fixture (for a total of four doors). The doors could be opened or closed to the free-stream airflow during flight at angles of 0, 15, 30, 45, and 60 degrees. The WP-3D tile testing concentrated on observing the effects of larger drops of moisture at lower speeds. The principle investigator for the tile tests was Robert R. Meyer, Jr., NASA engineer, Ames-Dryden Flight Research Facility (now Director of Research Engineering, Dryen Flight Research Center.) The Department of Commerce WP-3D aircraft was based at the Miami International Airport. It served as an environmental research platform for oceanographic and atmospheric studies by various government agencies and universities. The WP-3D flown in the Shuttle tile tests was specially instrumented for scientific observation with three radars and an onboard data recording capability. The pylon used for the tile tests could be configured so that specialized equipment could be installed for different users in the scientific community.

1987-01-01

86

Flight Test Results of a Thermoelectric Energy Harvester for Aircraft  

NASA Astrophysics Data System (ADS)

The idea of thermoelectric energy harvesting for low-power wireless sensor systems in aircraft and its practical implementation was recently published. The concept of using a thermoelectric generator (TEG) attached to the aircraft inner hull and a thermal storage device to create an artificial temperature gradient at the TEG during take-off and landing from the temperature changes of the fuselage has passed initial tests and is now subject to flight testing. This work presents preflight test results, e.g., vibration and temperature testing of the harvesters, the practical installation of two harvesting devices inside a test plane, and the first test flight results. Several flight cycles with different flight profiles, flight lengths, and outside temperatures have been performed. Although the influence of different flight profiles on the energy output of the harvester can be clearly observed, the results are in good agreement with expectations from numerical simulations with boundary conditions evaluated from initial climate chamber experiments. In addition, the flight test demonstrates that reliable operation of thermoelectric energy harvesting in harsh aircraft environments seems to be feasible, therefore paving the way for realization of energy-autonomous, wireless sensor networks.

Samson, D.; Kluge, M.; Fuss, T.; Schmid, U.; Becker, Th.

2012-06-01

87

Safe automatic flight back and landing of aircraft flight reconfiguration function (FRF)  

Microsoft Academic Search

SOFIA (Safe Automatic Flight Back and Landing of Aircraft) project is a response to the challenge of developing concepts and techniques enabling the safe and automatic return to ground in the event of hostile actions. Activities in this sense have been started in the framework of the SAFEE SP3 (Secure Aircraft in the Future European Environment Sub-Project 3) project. SOFIA

Juan Alberto Herrería García

2008-01-01

88

Safe Automatic Flight Back and Landing of Aircraft Flight Reconfiguration Function (FRF)  

Microsoft Academic Search

SOFIA (safe automatic flight back and landing of aircraft) project is a response to the challenge of developing concepts and techniques enabling the safe and automatic return to ground in the event of hostile actions. Activities in this sense have been started in the framework of the SAFEE SP3 (secure aircraft in the future european environment sub-project 3) project. SOFIA

Juan Alberto Herreria Garcia

2008-01-01

89

Flight experience with manually controlled unconventional aircraft motions  

NASA Technical Reports Server (NTRS)

A modified YF-16 aircraft was used to flight demonstrate decoupled modes under the USAF Fighter Control Configured Vehicle (CCV) Program. The direct force capabilities were used to implement seven manually controlled unconventional modes on the aircraft, allowing flat turns, decoupled normal acceleration control, independent longitudinal and lateral translations, uncoupled elevation and azimuth aiming, and blended direct lift. This paper describes the design, development, and flight testing of these control modes. The need for task-tailored mode authorities, gain-scheduling and selected closed-loop design is discussed.

Barfield, A. F.

1978-01-01

90

Aircraft Configured for Flight in an Atmosphere Having Low Density  

NASA Technical Reports Server (NTRS)

An aircraft is configured for flight in an atmosphere having a low density. The aircraft includes a fuselage, a pair of wings, and a rear stabilizer. The pair of wings extends from the fuselage in opposition to one another. The rear stabilizer extends from the fuselage in spaced relationship to the pair of wings. The fuselage, the wings, and the rear stabilizer each present an upper surface opposing a lower surface. The upper and lower surfaces have X, Y, and Z coordinates that are configured for flight in an atmosphere having low density.

Croom, Mark A. (Inventor); Smith, Stephen C. (Inventor); Gelhausen, Paul A. (Inventor); Guynn, Mark D. (Inventor); Hunter, Craig A. (Inventor); Paddock, David A. (Inventor); Riddick, Steven E. (Inventor); Teter, Jr., John E. (Inventor)

2012-01-01

91

41 CFR 102-36.345 - May we dispose of excess Flight Safety Critical Aircraft Parts (FSCAP)?  

Code of Federal Regulations, 2014 CFR

...we dispose of excess Flight Safety Critical Aircraft Parts (FSCAP)? 102-36...Special Handling Aircraft and Aircraft Parts § 102-36.345 May we dispose of excess Flight Safety Critical Aircraft Parts...

2014-01-01

92

41 CFR 102-36.345 - May we dispose of excess Flight Safety Critical Aircraft Parts (FSCAP)?  

Code of Federal Regulations, 2011 CFR

...we dispose of excess Flight Safety Critical Aircraft Parts (FSCAP)? 102-36...Special Handling Aircraft and Aircraft Parts § 102-36.345 May we dispose of excess Flight Safety Critical Aircraft Parts...

2011-01-01

93

41 CFR 102-36.345 - May we dispose of excess Flight Safety Critical Aircraft Parts (FSCAP)?  

Code of Federal Regulations, 2012 CFR

...we dispose of excess Flight Safety Critical Aircraft Parts (FSCAP)? 102-36...Special Handling Aircraft and Aircraft Parts § 102-36.345 May we dispose of excess Flight Safety Critical Aircraft Parts...

2012-01-01

94

41 CFR 102-36.345 - May we dispose of excess Flight Safety Critical Aircraft Parts (FSCAP)?  

Code of Federal Regulations, 2010 CFR

...we dispose of excess Flight Safety Critical Aircraft Parts (FSCAP)? 102-36...Special Handling Aircraft and Aircraft Parts § 102-36.345 May we dispose of excess Flight Safety Critical Aircraft Parts...

2010-07-01

95

41 CFR 102-36.345 - May we dispose of excess Flight Safety Critical Aircraft Parts (FSCAP)?  

Code of Federal Regulations, 2013 CFR

...we dispose of excess Flight Safety Critical Aircraft Parts (FSCAP)? 102-36...Special Handling Aircraft and Aircraft Parts § 102-36.345 May we dispose of excess Flight Safety Critical Aircraft Parts...

2013-07-01

96

Propeller aircraft noise-certification and flight testing  

NASA Astrophysics Data System (ADS)

Specifications for controlling aircraft noise emission and emission as developed by the ICAO and presently entitled International Standards and Recommended Practices - Environmental Protection, ANNEX 16 to the Convention on International Civil Aviation/ Volume 1, Aircraft Noise are elaborated. Those portions dealing with the noise certification of heavy (commuter and transport) and light (sports and recreational) propeller driven aircraft are discussed. Some information on the practice of noise certification data acquisition and evaluation, based on several hundred measurements, are provided. Current ideas towards changing, consolidating, and improving the present schemes and procedures are described. Specific acoustic problem areas in flight testing and analysis are also covered.

Heller, H.

97

41 CFR 102-33.115 - Are there special requirements for acquiring military Flight Safety Critical Aircraft Parts (FSCAP)?  

Code of Federal Regulations, 2011 CFR

...acquiring military Flight Safety Critical Aircraft Parts (FSCAP)? 102-33...acquiring military Flight Safety Critical Aircraft Parts (FSCAP)? Yes...acquire military Flight Safety Critical Aircraft Parts (FSCAP), you...

2011-01-01

98

41 CFR 102-33.115 - Are there special requirements for acquiring military Flight Safety Critical Aircraft Parts (FSCAP)?  

Code of Federal Regulations, 2012 CFR

...acquiring military Flight Safety Critical Aircraft Parts (FSCAP)? 102-33...acquiring military Flight Safety Critical Aircraft Parts (FSCAP)? Yes...acquire military Flight Safety Critical Aircraft Parts (FSCAP), you...

2012-01-01

99

41 CFR 102-33.115 - Are there special requirements for acquiring military Flight Safety Critical Aircraft Parts (FSCAP)?  

Code of Federal Regulations, 2013 CFR

...acquiring military Flight Safety Critical Aircraft Parts (FSCAP)? 102-33...acquiring military Flight Safety Critical Aircraft Parts (FSCAP)? Yes...acquire military Flight Safety Critical Aircraft Parts (FSCAP), you...

2013-07-01

100

41 CFR 102-33.115 - Are there special requirements for acquiring military Flight Safety Critical Aircraft Parts (FSCAP)?  

Code of Federal Regulations, 2010 CFR

...acquiring military Flight Safety Critical Aircraft Parts (FSCAP)? 102-33...acquiring military Flight Safety Critical Aircraft Parts (FSCAP)? Yes...acquire military Flight Safety Critical Aircraft Parts (FSCAP), you...

2010-07-01

101

41 CFR 102-33.115 - Are there special requirements for acquiring military Flight Safety Critical Aircraft Parts (FSCAP)?  

Code of Federal Regulations, 2014 CFR

...acquiring military Flight Safety Critical Aircraft Parts (FSCAP)? 102-33...acquiring military Flight Safety Critical Aircraft Parts (FSCAP)? Yes...acquire military Flight Safety Critical Aircraft Parts (FSCAP), you...

2014-01-01

102

Knowledge-based processing for aircraft flight control  

NASA Technical Reports Server (NTRS)

The purpose is to develop algorithms and architectures for embedding artificial intelligence in aircraft guidance and control systems. With the approach adopted, AI-computing is used to create an outer guidance loop for driving the usual aircraft autopilot. That is, a symbolic processor monitors the operation and performance of the aircraft. Then, based on rules and other stored knowledge, commands are automatically formulated for driving the autopilot so as to accomplish desired flight operations. The focus is on developing a software system which can respond to linguistic instructions, input in a standard format, so as to formulate a sequence of simple commands to the autopilot. The instructions might be a fairly complex flight clearance, input either manually or by data-link. Emphasis is on a software system which responds much like a pilot would, employing not only precise computations, but, also, knowledge which is less precise, but more like common-sense. The approach is based on prior work to develop a generic 'shell' architecture for an AI-processor, which may be tailored to many applications by describing the application in appropriate processor data bases (libraries). Such descriptions include numerical models of the aircraft and flight control system, as well as symbolic (linguistic) descriptions of flight operations, rules, and tactics.

Painter, John H.

1991-01-01

103

Integrated Flight and Propulsion Controls for Advanced Aircraft Configurations  

NASA Technical Reports Server (NTRS)

The research vision of the NASA Lewis Research Center in the area of integrated flight and propulsion controls technologies is described. In particular, the integrated method for propulsion and airframe controls developed at the Lewis Research Center is described including its application to an advanced aircraft configuration. Additionally, future research directions in integrated controls are described.

Merrill, Walter; Garg, Sanjay

1996-01-01

104

Integrated Flight and Propulsion Controls for Advanced Aircraft Configurations  

NASA Technical Reports Server (NTRS)

The research vision of the NASA Lewis Research Center in the area of integrated flight and propulsion controls technologies is described. In particular the Integrated Method for Propulsion and Airframe Controls developed at the Lewis Research Center is described including its application to an advanced aircraft configuration. Additionally, future research directions in integrated controls are described.

Merrill, Walter; Garg, Sanjay

1995-01-01

105

X-31 Enhanced Fighter Maneuverability Aircraft in Flight  

NASA Technical Reports Server (NTRS)

The X-31 Enhanced Fighter Maneuverability aircraft in flight over California's Mojave desert during a 1992 test flight. The X-31 Enhanced Fighter Maneuverability (EFM) demonstrator flew at the Ames- Dryden Flight Research Facility, Edwards, California (redesignated the Dryden Flight Research Center in 1994) from February 1992 until 1995 and before that at the Air Force's Plant 42 in Palmdale, California. The goal of the project was to provide design information for the next generation of highly maneuverable fighter aircraft. This program demonstrated the value of using thrust vectoring (directing engine exhaust flow) coupled with an advanced flight control system to provide controlled flight to very high angles of attack. The result was a significant advantage over most conventional fighters in close-in combat situations. The X-31 flight program focused on agile flight within the post-stall regime, producing technical data to give aircraft designers a better understanding of aerodynamics, effectiveness of flight controls and thrust vectoring, and airflow phenomena at high angles of attack. Stall is a condition of an airplane or an airfoil in which lift decreases and drag increases due to the separation of airflow. Thrust vectoring compensates for the loss of control through normal aerodynamic surfaces that occurs during a stall. Post-stall refers to flying beyond the normal stall angle of attack, which in the X-31 was at a 30-degree angle of attack. During Dryden flight testing, the X-31 aircraft established several milestones. On November 6, 1992, the X-31 achieved controlled flight at a 70-degree angle of attack. On April 29, 1993, the second X-31 successfully executed a rapid minimum-radius, 180-degree turn using a post-stall maneuver, flying well beyond the aerodynamic limits of any conventional aircraft. This revolutionary maneuver has been called the 'Herbst Maneuver' after Wolfgang Herbst, a German proponent of using post-stall flight in air-to-air combat. It is also called a 'J Turn' when flown to an arbitrary heading change. The aircraft was flown in tactical maneuvers against an F/A-18 and other tactical aircraft as part of the test flight program. During November and December 1993, the X-31 reached a supersonic speed of Mach 1.28. In 1994, the X-31 program installed software to demonstrate quasi-tailless operation. The X-31 flight test program was conducted by an international test organization (ITO) managed by the Advanced Research Projects Office (ARPA), known as the Defense Advanced Research Projects Office (DARPA) before March 1993. The ITO included the U.S. Navy and U.S. Air Force, Rockwell Aerospace, the Federal Republic of Germany, Daimler-Benz (formerly Messerschmitt-Bolkow-Blohm and Deutsche Aerospace), and NASA. Gary Trippensee was the ITO director and NASA Project Manager. Pilots came from participating organizations. The X-31 was 43.33 feet long with a wingspan of 23.83 feet. It was powered by a single General Electric P404-GE-400 turbofan engine that produced 16,000 pounds of thrust in afterburner.

1992-01-01

106

EOS Aqua AMSR-E Arctic Sea Ice Validation Program: Arctic2003 Aircraft Campaign Flight Report  

NASA Technical Reports Server (NTRS)

In March 2003 a coordinated Arctic sea ice validation field campaign using the NASA Wallops P-3B aircraft was successfully completed. This campaign was part of the program for validating the Earth Observing System (EOS) Aqua Advanced Microwave Scanning Radiometer (AMSR-E) sea ice products. The AMSR-E, designed and built by the Japanese National Space Development Agency for NASA, was launched May 4, 2002 on the EOS Aqua spacecraft. The AMSR-E sea ice products to be validated include sea ice concentration, sea ice temperature, and snow depth on sea ice. This flight report describes the suite of instruments flown on the P-3, the objectives of each of the seven flights, the Arctic regions overflown, and the coordination among satellite, aircraft, and surface-based measurements. Two of the seven aircraft flights were coordinated with scientists making surface measurements of snow and ice properties including sea ice temperature and snow depth on sea ice at a study area near Barrow, AK and at a Navy ice camp located in the Beaufort Sea. Two additional flights were dedicated to making heat and moisture flux measurements over the St. Lawrence Island polynya to support ongoing air-sea-ice processes studies of Arctic coastal polynyas. The remaining flights covered portions of the Bering Sea ice edge, the Chukchi Sea, and Norton Sound.

Cavalieri, D. J.; Markus,T.

2003-01-01

107

Neural networks in nonlinear aircraft flight control  

Microsoft Academic Search

This paper describes an approach for incorporating a neural network with real-time learning capability in a flight control architecture. The architecture is also applicable, in general, for the control of processes described by nonlinear differential equations of motion in which there exists a control for each degree of freedom. The main features are that the defining equations of motion for

Anthony J. Calise

1996-01-01

108

Neural networks in nonlinear aircraft flight control  

Microsoft Academic Search

This paper describes an approach for incorporating a neural network with real-time learning capability in a flight control architecture. The architecture is also applicable in general for the control of processes described by nonlinear differential equations of motion in which there exists a control for each degree of freedom. The main features are that the defining equations of motion for

Anthony J. Calise

1995-01-01

109

Longitudinal flying qualities criteria for single-pilot instrument flight operations  

NASA Technical Reports Server (NTRS)

Modern estimation and control theory, flight testing, and statistical analysis were used to deduce flying qualities criteria for General Aviation Single Pilot Instrument Flight Rule (SPIFR) operations. The principal concern is that unsatisfactory aircraft dynamic response combined with high navigation/communication workload can produce problems of safety and efficiency. To alleviate these problems. The relative importance of these factors must be determined. This objective was achieved by flying SPIFR tasks with different aircraft dynamic configurations and assessing the effects of such variations under these conditions. The experimental results yielded quantitative indicators of pilot's performance and workload, and for each of them, multivariate regression was applied to evaluate several candidate flying qualities criteria.

Stengel, R. F.; Bar-Gill, A.

1983-01-01

110

Eye scanning behavior as a discriminator of instrument- and scenery-centered flight task.  

PubMed

Aircraft pilot's eye scanning behavior represented by saccadic amplitudes and dwelling time of eye movements is a promising indicator of discrimination whether some flight task is instrument- or scenery-centered. The saccadic amplitude seems to reflect spatial and temporal values of target information. The dwelling time or gaze duration reflects the changing rate of visual information, amounts extracted from and density and complexity of the target information, or experience level of a relevant pilot. This study is for confirming the validity of the above indicator to discriminate the two types of flight tasks, instrument- and scenery-centered tasks. Five jet aircraft pilots, aged 25 to 32, participated in this experiment. A flight simulator equipped with a computer generated visual scene (field of view: 116 degree (H) x 25 degree (V)) was used. Five kinds of flight tasks were selected. These were takeoff, level flight, low-airspeed flight, acrobatic flight (minimum timed turn), and landing. These tasks were selected with the difference in degree of instrument- or scenery-centered flight, by the pilots' comments. Eye movements during simulator flight were recorded by a conventional electrooculographic apparatus with an 12-channel polygraph system. Analogue data from the amplifiers was digitized at a sampling rate of 2 kHz, and stored in a computer system. Horizontal components of eye movements by flight task were analyzed. Mean saccadic amplitudes (microV) showed significant differences among flight tasks, and no significance between subjects was obtained. The largest mean amplitude was in the acrobatic flight, and the smallest was in the low-airspeed flight.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8522800

Katoh, Z; Kadoo, A; Itoh, H; Maruta, H

1995-06-01

111

In-flight Fault Detection and Isolation in Aircraft Flight Control Systems  

NASA Technical Reports Server (NTRS)

In this paper we consider the problem of test design for real-time fault detection and isolation (FDI) in the flight control system of fixed-wing aircraft. We focus on the faults that are manifested in the control surface elements (e.g., aileron, elevator, rudder and stabilizer) of an aircraft. For demonstration purposes, we restrict our focus on the faults belonging to nine basic fault classes. The diagnostic tests are performed on the features extracted from fifty monitored system parameters. The proposed tests are able to uniquely isolate each of the faults at almost all severity levels. A neural network-based flight control simulator, FLTZ(Registered TradeMark), is used for the simulation of various faults in fixed-wing aircraft flight control systems for the purpose of FDI.

Azam, Mohammad; Pattipati, Krishna; Allanach, Jeffrey; Poll, Scott; Patterson-Hine, Ann

2005-01-01

112

An Evaluation Technique for an F/A-18 Aircraft Loads Model Using F/A-18 Systems Research Aircraft Flight Data  

NASA Technical Reports Server (NTRS)

A limited evaluation of the F/A-18 baseline loads model was performed on the Systems Research Aircraft at NASA Dryden Flight Research Center (Edwards, California). Boeing developed the F/A-18 loads model using a linear aeroelastic analysis in conjunction with a flight simulator to determine loads at discrete locations on the aircraft. This experiment was designed so that analysis of doublets could be used to establish aircraft aerodynamic and loads response at 20 flight conditions. Instrumentation on the right outboard leading edge flap, left aileron, and left stabilator measured the hinge moment so that comparisons could be made between in-flight-measured hinge moments and loads model-predicted values at these locations. Comparisons showed that the difference between the loads model-predicted and in-flight-measured hinge moments was up to 130 percent of the flight limit load. A stepwise regression technique was used to determine new loads derivatives. These derivatives were placed in the loads model, which reduced the error to within 10 percent of the flight limit load. This paper discusses the flight test methodology, a process for determining loads coefficients, and the direct comparisons of predicted and measured hinge moments and loads coefficients.

Olney, Candida D.; Hillebrandt, Heather; Reichenbach, Eric Y.

2000-01-01

113

Autonomous Flight Safety System September 27, 2005, Aircraft Test  

NASA Technical Reports Server (NTRS)

This report describes the first aircraft test of the Autonomous Flight Safety System (AFSS). The test was conducted on September 27, 2005, near Kennedy Space Center (KSC) using a privately-owned single-engine plane and evaluated the performance of several basic flight safety rules using real-time data onboard a moving aerial vehicle. This test follows the first road test of AFSS conducted in February 2005 at KSC. AFSS is a joint KSC and Wallops Flight Facility (WEF) project that is in its third phase of development. AFSS is an independent subsystem intended for use with Expendable Launch Vehicles that uses tracking data from redundant onboard sensors to autonomously make flight termination decisions using software-based rules implemented on redundant flight processors. The goals of this project are to increase capabilities by allowing launches from locations that do not have or cannot afford extensive ground-based range safety assets, to decrease range costs, and to decrease reaction time for special situations. The mission rules are configured for each operation by the responsible Range Safety authorities and can be loosely categorized in four major categories: Parameter Threshold Violations, Physical Boundary Violations present position and instantaneous impact point (TIP), Gate Rules static and dynamic, and a Green-Time Rule. Examples of each of these rules were evaluated during this aircraft test.

Simpson, James C.

2005-01-01

114

An improved aircraft underflight instrument for the derivation of band gains in satellite sensors  

Microsoft Academic Search

There is an increasing need for improved in-flight calibration of visible and near-IR satellite sensors to gather reliable information on global climate mechanisms and climate change. Satellite instruments for the near future, such as MODIS and SeaWiFS, require accurate calibration throughout their lifetimes on orbit, and represent a challenging task. Flying a calibrated transfer spectroradiometer on a high altitude aircraft

P. Abel; B. Subramanya

1996-01-01

115

Modeling flight attendants' exposures to pesticide in disinsected aircraft cabins.  

PubMed

Aircraft cabin disinsection is required by some countries to kill insects that may pose risks to public health and native ecological systems. A probabilistic model has been developed by considering the microenvironmental dynamics of the pesticide in conjunction with the activity patterns of flight attendants, to assess their exposures and risks to pesticide in disinsected aircraft cabins under three scenarios of pesticide application. Main processes considered in the model are microenvironmental transport and deposition, volatilization, and transfer of pesticide when passengers and flight attendants come in contact with the cabin surfaces. The simulated pesticide airborne mass concentration and surface mass loadings captured measured ranges reported in the literature. The medians (means ± standard devitions) of daily total exposure intakes were 0.24 (3.8 ± 10.0), 1.4 (4.2 ± 5.7), and 0.15 (2.1 ± 3.2) ?g day(-1) kg(-1) of body weight for scenarios of residual application, preflight, and top-of-descent spraying, respectively. Exposure estimates were sensitive to parameters corresponding to pesticide deposition, body surface area and weight, surface-to-body transfer efficiencies, and efficiency of adherence to skin. Preflight spray posed 2.0 and 3.1 times higher pesticide exposure risk levels for flight attendants in disinsected aircraft cabins than top-of-descent spray and residual application, respectively. PMID:24251734

Zhang, Yong; Isukapalli, Sastry; Georgopoulos, Panos; Weisel, Clifford

2013-12-17

116

Modeling Flight Attendants’ Exposures to Pesticide in Disinsected Aircraft Cabins  

PubMed Central

Aircraft cabin disinsection is required by some countries to kill insects that may pose risks to public health and native ecological systems. A probabilistic model has been developed by considering the microenvironmental dynamics of the pesticide in conjunction with the activity patterns of flight attendants, to assess their exposures and risks to pesticide in disinsected aircraft cabins under three scenarios of pesticide application. Main processes considered in the model are microenvironmental transport and deposition, volatilization, and transfer of pesticide when passengers and flight attendants come in contact with the cabin surfaces. The simulated pesticide airborne mass concentration and surface mass loadings captured measured ranges reported in the literature. The medians (means±standard devitions) of daily total exposures intakes were 0.24 (3.8±10.0), 1.4 (4.2±5.7) and 0.15 (2.1±3.2) ?g/(day kg BW) for scenarios of Residual Application, Preflight and Top-of-Descent spraying, respectively. Exposure estimates were sensitive to parameters corresponding to pesticide deposition, body surface area and weight, surface-to-body transfer efficiencies, and efficiency of adherence to skin. Preflight spray posed 2.0 and 3.1 times higher pesticide exposure risk levels for flight attendants in disinsected aircraft cabins than Top-of-Descent spray and Residual Application, respectively. PMID:24251734

Zhang, Yong; Isukapalli, Sastry; Georgopoulos, Panos; Weisel, Clifford

2014-01-01

117

In-flight detection and identification and accommodation of aircraft icing  

NASA Astrophysics Data System (ADS)

The recent improvements and research on aviation have focused on the subject of aircraft safe flight even in the severe weather conditions. As one type of such weather conditions, aircraft icing considerably has negative effects on the aircraft flight performance. The risks of the iced aerodynamic surfaces of the flying aircraft have been known since the beginning of the first flights. Until recent years, as a solution for this event, the icing conditions ahead flight route are estimated from radars or other environmental sensors, hence flight paths are changed, or, if it exists, anti-icing/de-icing systems are used. This work aims at the detection and identification of airframe icing based on statistical properties of aircraft dynamics and reconfigurable control protecting aircraft from hazardous icing conditions. In this paper, aircraft icing identification based on neural networks is investigated. Following icing identification, reconfigurable control is applied for protecting the aircraft from hazardous icing conditions.

Caliskan, Fikret; Hajiyev, Chingiz

2012-11-01

118

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

NASA Technical Reports Server (NTRS)

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.

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

1981-01-01

119

Applied Mathematical Sciences, Vol. 6, 2012, no. 25, 1221 -1249 Aircraft Flight Path Optimization  

E-print Network

depends on the ight dynamics of the aircraft and considers ight safety and stability re- quirementsApplied Mathematical Sciences, Vol. 6, 2012, no. 25, 1221 - 1249 Aircraft Flight Path Optimization.khardi@ifsttar.fr )>IJH=?J Flight path optimization is designed for minimizing aircraft noise, fuel consumption and air

Paris-Sud XI, Université de

120

Experts discuss handling qualities and flight deck requirements of next generation transport aircraft  

E-print Network

aircraft The Society of Automotive Engineers' (SAE) S7-Commitee "Flight Deck & Handling Qualities Standards for Transport Aircraft" met from 15 to 18 May 2006 at TU Berlin to define standards for the design of future flight decks and to discuss handling quality requirements for modern transport aircraft. The meeting

Berlin,Technische Universität

121

14 CFR Appendix A to Part 65 - Aircraft Dispatcher Courses  

Code of Federal Regulations, 2013 CFR

...Instruments. F. Instrument Approach Procedures...Flight Manual. B. Systems Overview. (1) Flight...Procedures. (9) Fuel Systems and Sources. C...Balance. (5) Flight instrument errors. (6) Aircraft...performance. (c) Landing performance....

2013-01-01

122

14 CFR Appendix A to Part 65 - Aircraft Dispatcher Courses  

Code of Federal Regulations, 2011 CFR

...Instruments. F. Instrument Approach Procedures...Flight Manual. B. Systems Overview. (1) Flight...Procedures. (9) Fuel Systems and Sources. C...Balance. (5) Flight instrument errors. (6) Aircraft...performance. (c) Landing performance....

2011-01-01

123

14 CFR Appendix A to Part 65 - Aircraft Dispatcher Courses  

Code of Federal Regulations, 2012 CFR

...Instruments. F. Instrument Approach Procedures...Flight Manual. B. Systems Overview. (1) Flight...Procedures. (9) Fuel Systems and Sources. C...Balance. (5) Flight instrument errors. (6) Aircraft...performance. (c) Landing performance....

2012-01-01

124

Realistic localizer courses for aircraft instrument landing simulators  

NASA Technical Reports Server (NTRS)

The realistic instrument landing simulator (ILS) course structures for use in aircraft simulators are described. Software developed for data conversion and translation of ILS course structure measurements and calcomp plots of the courses provided are described. A method of implementing the ILS course structure data in existing aircraft simulators is outlined. A cockpit used in the lab to review the digitized ILS course structures is displayed.

Murphy, T. A.

1984-01-01

125

Instruments and method of air navigation  

NASA Technical Reports Server (NTRS)

Topics discussed include magnetic and astronavigation instruments; flight beyond ground visibility; aircraft radio navigation instruments and communication radio sets; instrument landing systems; and ground controlled landing systems.

1977-01-01

126

The SR-71 Test Bed Aircraft: A Facility for High-Speed Flight Research  

NASA Technical Reports Server (NTRS)

The SR-71 test bed aircraft is shown to be a unique platform to flight-test large experiments to supersonic Mach numbers. The test bed hardware mounted on the SR-71 upper fuselage is described. This test bed hardware is composed of a fairing structure called the "canoe" and a large "reflection plane" flat plate for mounting experiments. Total experiment weights, including the canoe and reflection plane, as heavy as 14,500 lb can be mounted on the aircraft and flight-tested to speeds as fast as Mach 3.2 and altitudes as high as 80,000 ft. A brief description of the SR-71 aircraft is given, including details of the structural modifications to the fuselage, modifications to the J58 engines to provide increased thrust, and the addition of a research instrumentation system. Information is presented based on flight data that describes the SR-71 test bed aerodynamics, stability and control, structural and thermal loads, the canoe internal environment, and reflection plane flow quality. Guidelines for designing SR-71 test bed experiments are also provided.

Corda, Stephen; Moes, Timothy R.; Mizukami, Masashi; Hass, Neal E.; Jones, Daniel; Monaghan, Richard C.; Ray, Ronald J.; Jarvis, Michele L.; Palumbo, Nathan

2000-01-01

127

Application of human-machine modeling technique in the flight safety simulation of civil aircraft  

Microsoft Academic Search

The influence of pilot error and aircraft failure on the safety of civil aircraft is investigated in this paper. Based on the human-machine system modeling technique, the modules in the pilot-aircraft system failure mode are built using objective- oriented technique, and the software system of civil aircraft safety evaluation is developed. A practical example of flight accident shows that the

Wei Zhang; Zhi Ma; Hui Li; DaPeng Guo

2011-01-01

128

Centurion solar-powered high-altitude aircraft in flight  

NASA Technical Reports Server (NTRS)

Since 1980 AeroVironment, Inc. (founded in 1971 by the ultra-light airplane innovator--Dr. Paul MacCready) has been experimenting with solar-powered aircraft, often in conjunction with the NASA Dryden Flight Research Center, Edwards, California. Thus far, AeroVironment, now headquartered in Monrovia, California, has achieved several altitude records with its Solar Challenger, Pathfinder, and Pathfinder-Plus aircraft. It expects to exceed these records with the newer and larger solar-powered Centurion and its successors the Centelios and Helios vehicles, in the NASA Environmental Research Aircraft and Sensor Technology (ERAST) program. The Centurion is a lightweight, solar-powered, remotely piloted flying wing aircraft that is demonstrating the technology of applying solar power for long-duration, high-altitude flight. It is considered to be a prototype technology demonstrator for a future fleet of solar-powered aircraft that could stay airborne for weeks or months on scientific sampling and imaging missions or while serving as telecommunications relay platforms. Although it shares many of the design concepts of the Pathfinder, the Centurion has a wingspan of 206 feet, more than twice the 98-foot span of the original Pathfinder and 70-percent longer than the Pathfinder-Plus' 121-foot span. At the same time, Centurion maintains the 8-foot chord (front to rear distance) of the Pathfinder wing, giving the wing an aspect ratio (length-to-chord) of 26 to 1. Other visible changes from its predecessor include a modified wing airfoil designed for flight at extreme altitude and four underwing pods to support its landing gear and electronic systems (compared with two such pods on the Pathfinder). The flexible wing is primarily fabricated from carbon fiber, graphite epoxy composites, and kevlar. It is built in five sections, a 44-foot-long center section and middle and outer sections just over 40 feet long. All five sections have an identical thickness--12 percent of the chord, or about 11.5 inches, with no taper or sweep. Solar arrays that will cover most of the upper wing surface will provide up to 31 kilowatts of power at high noon on a summer day to power the aircraft's 14 electric motors, avionics, communications and other electronic systems. Centurion also has a backup lithium battery system that can provide power for between two and five hours to allow limited-duration flight after dark. Initial low-altitude test flights at Dryden in 1998 were conducted on battery power alone, prior to installation of the solar cell arrays. Centurion flies at an airspeed of only 17 to 21 mph, or about 15 to 18 knots. Although pitch control is maintained by the use of a full-span 60-segment elevator on the trailing edge of the wing, turns and yaw control are accomplished by applying differential power -- slowing down or speeding up the motors -- on the outboard sections of the wing. The video clip depicts the aircraft on the lakebed prior to and during its first low-altitude check flight under battery power on November 10, 1998.

1998-01-01

129

Single pilot scanning behavior in simulated instrument flight  

NASA Technical Reports Server (NTRS)

A simulation of tasks associated with single pilot general aviation flight under instrument flight rules was conducted as a baseline for future research studies on advanced flight controls and avionics. The tasks, ranging from simple climbs and turns to an instrument landing systems approach, were flown on a fixed base simulator. During the simulation the control inputs, state variables, and the pilots visual scan pattern including point of regard were measured and recorded.

Pennington, J. E.

1979-01-01

130

Flight Test of ASAC Aircraft Interior Noise Control System  

NASA Technical Reports Server (NTRS)

A flight test is described in which an active structural/acoustic control system reduces turboprop induced interior noise on a Raytheon Aircraft Company 1900D airliner. Control inputs to 21 inertial force actuators were computed adaptively using a transform domain version of the multichannel filtered-X LMS algorithm to minimize the mean square response of 32 microphones. A combinatorial search algorithm was employed to optimize placement of the force actuators on the aircraft frame. Both single frequency and multi-frequency results are presented. Reductions of up to 15 dB were obtained at the blade passage frequency (BPF) during single frequency control tests. Simultaneous reductions of the BPF and next 2 harmonics of 10 dB, 2.5 dB and 3.0 dB, were obtained in a multi-frequency test.

Palumbo, Dan; Cabell, Ran; Cline, John; Sullivan, Brenda

1999-01-01

131

Flight Dynamics Modeling and Simulation of a Damaged Transport Aircraft  

NASA Technical Reports Server (NTRS)

A study was undertaken at NASA Langley Research Center to establish, demonstrate, and apply methodology for modeling and implementing the aerodynamic effects of MANPADS damage to a transport aircraft into real-time flight simulation, and to demonstrate a preliminary capability of using such a simulation to conduct an assessment of aircraft survivability. Key findings from this study include: superpositioning of incremental aerodynamic characteristics to the baseline simulation aerodynamic model proved to be a simple and effective way of modeling damage effects; the primary effect of wing damage rolling moment asymmetry may limit minimum airspeed for adequate controllability, but this can be mitigated by the use of sideslip; combined effects of aerodynamics, control degradation, and thrust loss can result in significantly degraded controllability for a safe landing; and high landing speeds may be required to maintain adequate control if large excursions from the nominal approach path are allowed, but high-gain pilot control during landing can mitigate this risk.

Shah, Gautam H.; Hill, Melissa A.

2012-01-01

132

Flight test techniques for aircraft parameter estimation in ground effect  

E-print Network

^ Aircraft motion can be divided into two separate modes, the longitudinal (Equation (1)) and the lateral-directional (Equation (2)), which are independent for most maneuvers and can be treated separately. In these equations, the X, Y, Zt L, Mf 17 and N....0800 c h = 8.1000 CD = 0.0000 c = -34.0000 CLse = 0.5800 CDSe = 0.0000 c -1.9000 Note: Angular parameters are per radian. With the parameters and other values for the approach flight condition substituted into Equation 4, the longitudinal linear...

Clark, James Matthew

1993-01-01

133

An intercomparison of aircraft instrumentation for tropospheric measurements of sulfur dioxide  

NASA Technical Reports Server (NTRS)

As part of the NASA Tropospheric Chemistry Program, a series of field intercomparisons have been conducted to evaluate the state-of-the art for measuring key tropospheric species. One of the objectives of the third intercomparison campaign in this series, Chemical Instrumentation Test and Evaluation 3 (CITE 3), was to evaluate instrumentation for making reliable tropospheric aircraft measurements of sulfur dioxide, dimethyl sulfide, hydrogen sulfide, carbon disulfide, and carbonyl sulfide. This paper reports the results of the intercomparisons of five sulfur dioxide measurement methods ranging from filter techniques, in which samples collected in flight are returned to the laboratory for analyses (chemiluminescent or ion chromatographic), to near real-time, in-flight measurements via gas chromatographic, mass spectrometric, and chemiluminescent techniques. All techniques showed some tendency to track sizeable changes in ambient SO2 such as those associated with altitude changes. For SO2 mixing ratios in the range of 200 pptv to a few ppbv, agreement among the techniques varies from about 30% to several orders of magnitude, depending upon the pair of measurements intercompared. For SO2 mixing ratios less than 200 pptv, measurements from the techniques are uncorrelated. In general, observed differences in the measurement of standards do not account for the flight results. The CITE 3 results do not unambiguously identify one or more of the measurement techniques as providing valid or invalid SO2 measurements, but identify the range of 'potential' uncertainty in SO2 measurements reported by currently available instrumentation and as measured under realistic aircraft environments.

Gregory, Gerald L.; Davis, Douglas D.; Beltz, Nobert; Bandy, Alan R.; Ferek, Ronald J.; Thornton, Donald C.

1993-01-01

134

Aeroacoustics: Acoustic wave propagation; Aircraft noise prediction; Aeroacoustic instrumentation  

Microsoft Academic Search

The papers in this volume deal with recent research into acoustic-wave propagation through the atmosphere and progress in aeroacoustic instrumentation, facilities, and test techniques. Topics include the propagation of aircraft noise over long distances in the lower atmosphere, measured effects of turbulence on the rise time of a weak shock, sound scattering from atmospheric turbulence, saturation effects associated with sound

I. R. Schwartz

1976-01-01

135

NASA's Shuttle Carrier Aircraft 911's Final Flight - Duration: 1:35.  

NASA Video Gallery

NASA 911, one of NASA's two modified Boeing 747 space shuttle carrier aircraft, flew its final flight Feb. 8, a short hop from NASA's Dryden Flight Research Center at Edwards Air Force Base to the ...

136

In-flight and simulated aircraft fuel temperature measurements  

NASA Technical Reports Server (NTRS)

Fuel tank measurements from ten flights of an L1011 commercial aircraft are reported for the first time. The flights were conducted from 1981 to 1983. A thermocouple rake was installed in an inboard wing tank and another in an outboard tank. During the test periods of either 2 or 5 hr, at altitudes of 10,700 m (35,000 ft) or higher, either the inboard or the outboard tank remained full. Fuel temperature profiles generally developed in the expected manner. The bulk fuel was mixed by natural convection to a nearly uniform temperature, especially in the outboard tank, and a gradient existed at the bottom conduction zone. The data indicated that when full, the upper surface of the inboard tank was wetted and the outboard tank was unwetted. Companion NASA Lewis Research Center tests were conducted in a 0.20 cubic meter (52 gal) tank simulator of the outboard tank, chilled on the top and bottom, and insulated on the sides. Even though the simulator tank had no internal components corresponding to the wing tank, temperatures agreed with the flight measurements for wetted upper surface conditions, but not for unwetted conditions. It was concluded that if boundary conditions are carefully controlled, simulators are a useful way of evaluating actual flight temperatures.

Svehla, Roger A.

1990-01-01

137

Quiet Short-Haul Research Aircraft - The first 3 years of flight research  

NASA Technical Reports Server (NTRS)

NASAs first three years of flight research in an investigation of terminal area flight operation with the Quiet Short-Haul Research Aircraft (QSRA) are presented. An initial flight and modification program was devoted to improving the capabilities of the QSRA and measuring its performance. Later programs included a joint program with the US Navy, a guest pilot program involving 23 pilots from 16 organizations, and a program to measure benefits of propulsive-lift to CTOL aircraft. Development flight research, complemented by the aircraft modification program, has resulted in improvements in the maximum lift coefficient of more than two units, and has greatly improved flight characteristics and handling qualities.

Cochrane, J. A.; Riddle, D. W.; Stevens, V. C.

1981-01-01

138

Calibration of strain-gage installations in aircraft structures for the measurement of flight loads  

NASA Technical Reports Server (NTRS)

A general method has been developed for calibrating strain-gage installations in aircraft structures, which permits the measurement in flight of the shear or lift, the bending moment, and the torque or pitching moment on the principal lifting or control surfaces. Although the stress in structural members may not be a simple function of the three loads of interest, a straightforward procedure is given for numerically combining the outputs of several bridges in such a way that the loads may be obtained. Extensions of the basic procedure by means of electrical combination of the strain-gage bridges are described which permit compromises between strain-gage installation time, availability of recording instruments, and data reduction time. The basic principles of strain-gage calibration procedures are illustrated by reference to the data for two aircraft structures of typical construction, one a straight and the other a swept horizontal stabilizer.

Skopinski, T H; Aiken, William S , Jr; Huston, Wilber B

1954-01-01

139

A wide field-of-view imaging DOAS instrument for continuous trace gas mapping from aircraft  

NASA Astrophysics Data System (ADS)

For the purpose of trace gas measurements and pollution mapping, the Airborne imaging DOAS instrument for Measurements of Atmospheric Pollution (AirMAP) has been developed, characterised and successfully operated from aircraft. From the observations with the AirMAP instrument nitrogen dioxide (NO2) columns were retrieved. A major benefit of the pushbroom imaging instrument is the spatially continuous, gap-free measurement sequence independent of flight altitude, a valuable characteristic for mapping purposes. This is made possible by the use of a frame-transfer detector. With a wide-angle entrance objective, a broad field-of-view across track of around 48° is achieved, leading to a swath width of about the same size as the flight altitude. The use of fibre coupled light intake optics with sorted light fibres allows flexible positioning within the aircraft and retains the very good imaging capabilities. The measurements yield ground spatial resolutions below 100 m. From a maximum of 35 individual viewing directions (lines of sight, LOS) represented by 35 single fibres, the number of viewing directions is adapted to each situation by averaging according to signal-to-noise or spatial resolution requirements. Exploitation of all the viewing directions yields observations at 30 m spatial resolution, making the instrument a suitable tool for mapping trace gas point sources and small scale variability. For accurate spatial mapping the position and aircraft attitude are taken into account using the Attitude and Heading Reference System of the aircraft. A first demonstration mission using AirMAP was undertaken. In June 2011, AirMAP has been operated on the AWI Polar-5 aircraft in the framework of the AIRMETH2011 campaign. During a flight above a medium sized coal-fired power plant in North-West Germany, AirMAP clearly detects the emission plume downwind from the exhaust stack, with NO2 vertical columns around 2 × 1016 molecules cm-2 in the plume center. The emission estimates are consistent with reports in the pollutant transfer register. Strong spatial gradients and variability in NO2 amounts across and along flight direction are observed, and small-scale enhancements of NO2 above a motorway are detected. The present study reports on the experimental setup and characteristics of AirMAP, and the first measurements at high spatial resolution and wide spatial coverage are presented which meet the requirements for NO2 mapping to observe and account for the intrinsic variability of tropospheric NO2.

Schönhardt, A.; Altube, P.; Gerilowski, K.; Krautwurst, S.; Hartmann, J.; Meier, A. C.; Richter, A.; Burrows, J. P.

2014-04-01

140

STDN network operations procedure for Apollo range instrumentation aircraft, revision 1  

NASA Technical Reports Server (NTRS)

The Apollo range instrumentation aircraft (ARIA) fleet which consists of four EC-135N aircraft used for Apollo communication support is discussed. The ARIA aircraft are used to provide coverage of lunar missions, earth orbit missions, command module/service module separation to spacecraft landing, and assist in recovery operations. Descriptions of ARIA aircraft, capabilities, and instrumentation are included.

Vette, A. R.; Pfeiffer, W. A.

1972-01-01

141

Operational Flight Testing of Early Instrument Landing Systems  

Microsoft Academic Search

The development of successful instrument approach and landing involved the solution of not only technical problems, but operational problems as well. A review of methods used to overcome operational problems is made, covering the period from the earliest successful instrument landing to the introduction of instrument approach into routine scheduled operation. Flight techniques are described, using early systems such as

E. A. Cutrell

1959-01-01

142

Miniaturized instrumentation for routine measurement of aerosol and gas phase pollution by lightweight autonomous unmanned aircraft.  

NASA Astrophysics Data System (ADS)

The upcoming California AUAV Pollution Profiling project (CAPPS) will routinely monitor the vertical distribution of aerosol and gas pollutants over California during 2008 using autonomous lightweight unmanned aircraft. The measurements will be used to evaluate the impact of pollutants on California's climate, detect long range transport, and to validate satellite measurements. Proven miniaturized instrumentation for collecting aerosol parameters (concentration, size distribution, absorption), atmospheric solar radiation (flux, heating rates, albedo) and meteorological parameters (thermodynamic structure, water vapor) that were flown during previous studies will be deployed. Validation of these instruments is reviewed. New miniaturized instruments to collect the concentration of gas species are being developed to compliment these established measurements. An ozone monitor with a resolution of 2 ppb has been successfully integrated into the flight package. Results from the laboratory validation of this instrument are presented. In addition, progress on a miniaturized carbon monoxide sensor and NOx sensor are also presented.

Corrigan, C. E.; Ramanathan, V.; Roberts, G.; Ramana, M. V.

2007-12-01

143

Modeling Aircraft Wing Loads from Flight Data Using Neural Networks  

NASA Technical Reports Server (NTRS)

Neural networks were used to model wing bending-moment loads, torsion loads, and control surface hinge-moments of the Active Aeroelastic Wing (AAW) aircraft. Accurate loads models are required for the development of control laws designed to increase roll performance through wing twist while not exceeding load limits. Inputs to the model include aircraft rates, accelerations, and control surface positions. Neural networks were chosen to model aircraft loads because they can account for uncharacterized nonlinear effects while retaining the capability to generalize. The accuracy of the neural network models was improved by first developing linear loads models to use as starting points for network training. Neural networks were then trained with flight data for rolls, loaded reversals, wind-up-turns, and individual control surface doublets for load excitation. Generalization was improved by using gain weighting and early stopping. Results are presented for neural network loads models of four wing loads and four control surface hinge moments at Mach 0.90 and an altitude of 15,000 ft. An average model prediction error reduction of 18.6 percent was calculated for the neural network models when compared to the linear models. This paper documents the input data conditioning, input parameter selection, structure, training, and validation of the neural network models.

Allen, Michael J.; Dibley, Ryan P.

2003-01-01

144

Apollo experience report: Development flight instrumentation. [telemetry equipment for space flight test program  

NASA Technical Reports Server (NTRS)

Development flight instrumentation was delivered for 25 Apollo vehicles as Government-furnished equipment. The problems and philosophies of an activity that was concerned with supplying telemetry equipment to a space-flight test program are discussed. Equipment delivery dates, system-design details, and flight-performance information for each mission also are included.

Farmer, N. B.

1974-01-01

145

Aircraft Flight Management with Actuator Major Failure Felix Mora-Camino, Sebastio Simes Cunha, Andrei Doncescu  

E-print Network

: aircraft flight safety, actuator failure, emergency management, non linear inverse control. I. INTRODUCTION at the French Civil Aviation Institute ­ ENAC, Automation and Operations Research Laboratory-LARA, AirAircraft Flight Management with Actuator Major Failure Felix Mora-Camino, Sebastião Simões Cunha

Boyer, Edmond

146

Full Flight Envelope Direct Thrust Measurement on a Supersonic Aircraft  

NASA Technical Reports Server (NTRS)

Direct thrust measurement using strain gages offers advantages over analytically-based thrust calculation methods. For flight test applications, the direct measurement method typically uses a simpler sensor arrangement and minimal data processing compared to analytical techniques, which normally require costly engine modeling and multisensor arrangements throughout the engine. Conversely, direct thrust measurement has historically produced less than desirable accuracy because of difficulty in mounting and calibrating the strain gages and the inability to account for secondary forces that influence the thrust reading at the engine mounts. Consequently, the strain-gage technique has normally been used for simple engine arrangements and primarily in the subsonic speed range. This paper presents the results of a strain gage-based direct thrust-measurement technique developed by the NASA Dryden Flight Research Center and successfully applied to the full flight envelope of an F-15 aircraft powered by two F100-PW-229 turbofan engines. Measurements have been obtained at quasi-steady-state operating conditions at maximum non-augmented and maximum augmented power throughout the altitude range of the vehicle and to a maximum speed of Mach 2.0 and are compared against results from two analytically-based thrust calculation methods. The strain-gage installation and calibration processes are also described.

Conners, Timothy R.; Sims, Robert L.

1998-01-01

147

Loss-of-Control: Perspectives on Flight Dynamics and Control of Impaired Aircraft  

E-print Network

Loss-of-Control: Perspectives on Flight Dynamics and Control of Impaired Aircraft Harry G. Kwatny, MD, 20705. Loss-of-Control (LOC) is a major factor in fatal aircraft accidents. Although definitions capability of the pilot to control the aircraft. In previous work we considered how the ability to regulate

Kwatny, Harry G.

148

Transfer of Instrument Training and the Synthetic Flight Training System.  

ERIC Educational Resources Information Center

One phase of an innovative flight training program, its development, and initial administration is described in this paper. The operational suitability test activities related to a determination of the transfer of instrument training value of the Army's Synthetic Flight Training System (SFTS) Device 2B24. Sixteen active Army members of an Officer…

Caro, Paul W.

149

A flight evaluation of methods for predicting vortex wake effects on trailing aircraft  

NASA Technical Reports Server (NTRS)

The results of four current analytical methods for predicting wing vortex strength and decay rate are compared with the results of a flight investigation of the wake characteristics of several large jet transport aircraft. An empirical expression defining the strength and decay rate of wake vortices is developed that best represents most of the flight-test data. However, the expression is not applicable to small aircraft that would be immersed in the vortex wake of large aircraft.

Robinson, G. H.; Larson, R. R.

1972-01-01

150

X-38 research aircraft - First drop flight and landing  

NASA Technical Reports Server (NTRS)

In the mid-1990's researchers at the NASA Dryden Flight Research Center, Edwards, California, and Johnson Space Center in Houston, Texas, began working actively with the sub-scale X-38 prototype crew return vehicle (CRV). This was an unpiloted lifting body designed at 80 percent of the size of a projected emergency crew return vehicle for the International Space Station. The X-38 and the actual CRV are patterned after a lifting-body shape first employed in the Air Force X-23 (SV-5) program in the mid-1960's and the Air Force-NASA X-24A lifting-body project in the early to mid-1970's. Built by Scaled Composites, Inc., in Mojave, California, and outfitted with avionics, computer systems, and other hardware at Johnson Space Center, two X-38 aircraft were involved in flight research at Dryden beginning in July of 1997. Before that, however, Dryden conducted some 13 flights at a drop zone near California City, California. Those tests were done with a 1/6-scale model of the X-38 aircraft to test the parafoil concept that would be employed on the X-38 and the actual CRV. The basic concept is that the actual CRV will use an inertial navigation system together with the Global Positioning System of satellites to guide it from the International Space Station into the Earth's atmosphere. A deorbit engine module will redirect the vehicle from orbit into the atmosphere where a series of parachutes and a parafoil will deploy in sequence to bring the vehicle to a landing, possibly in a field next to a hospital. Flight research at NASA Dryden for the X-38 began with an unpiloted captive carry flight in which the vehicle remained attached to its future launch vehicle the Dryden B-52 008. There were four captive flights in 1997 and three in 1998, plus the first drop test on March 12, 1998, using the parachutes and parafoil. Further captive and drop tests occurred in 1999. Although the X-38 landed safely on the lakebed at Edwards after the March 1998 drop test, there had been some problems with the parafoil. Intermediate parafoil tests at the Army Yuma Proving Grounds in Arizona enabled the project to resolve these problems and resume flight research. In the drop tests, the X-38 vehicles have been autonomous after airlaunch from the B-52. After they deploy the parafoil, they have remained autonomous, but there is also a manual mode that allows controls from the ground. The X-38 vehicles (designated V131 and V132) are each 24.5 feet long. The actual CRV to be flown in space is expected to be 30 feet long. This is a 16-second clip showing the X-38 vehicle toward the end of its first drop flight rapidly approaching the ground and then sliding to a landing in the desert test ranges at Edwards Air Force Base in California.

1998-01-01

151

SR-71A in Flight with Test Fixture Mounted Atop the Aft Section of the Aircraft  

NASA Technical Reports Server (NTRS)

This close-up, head-on view of NASA's SR-71A Blackbird in flight shows the aircraft with an experimental test fixture mounted on the back of the airplane. Two SR-71 aircraft have been used by NASA as testbeds for high-speed and high-altitude aeronautical research. The aircraft, an SR-71A and an SR-71B pilot trainer aircraft, have been based here at NASA's Dryden Flight Research Center, Edwards, California. They were transferred to NASA after the U.S. Air Force program was cancelled. As research platforms, the aircraft can cruise at Mach 3 for more than one hour. For thermal experiments, this can produce heat soak temperatures of over 600 degrees Fahrenheit (F). This operating environment makes these aircraft excellent platforms to carry out research and experiments in a variety of areas -- aerodynamics, propulsion, structures, thermal protection materials, high-speed and high-temperature instrumentation, atmospheric studies, and sonic boom characterization. The SR-71 was used in a program to study ways of reducing sonic booms or over pressures that are heard on the ground, much like sharp thunderclaps, when an aircraft exceeds the speed of sound. Data from this Sonic Boom Mitigation Study could eventually lead to aircraft designs that would reduce the 'peak' overpressures of sonic booms and minimize the startling affect they produce on the ground. One of the first major experiments to be flown in the NASA SR-71 program was a laser air data collection system. It used laser light instead of air pressure to produce airspeed and attitude reference data, such as angle of attack and sideslip, which are normally obtained with small tubes and vanes extending into the airstream. One of Dryden's SR-71s was used for the Linear Aerospike Rocket Engine, or LASRE Experiment. Another earlier project consisted of a series of flights using the SR-71 as a science camera platform for NASA's Jet Propulsion Laboratory in Pasadena, California. An upward-looking ultraviolet video camera placed in the SR-71's nosebay studied a variety of celestial objects in wavelengths that are blocked to ground-based astronomers. Earlier in its history, Dryden had a decade of past experience at sustained speeds above Mach 3. Two YF-12A aircraft and an SR-71 designated as a YF-12C were flown at the center between December 1969 and November 1979 in a joint NASA/USAF program to learn more about the capabilities and limitations of high-speed, high-altitude flight. The YF-12As were prototypes of a planned interceptor aircraft based on a design that later evolved into the SR-71 reconnaissance aircraft. Dave Lux was the NASA SR-71 project manger for much of the decade of the 1990s, followed by Steve Schmidt. Developed for the USAF as reconnaissance aircraft more than 30 years ago, SR-71s are still the world's fastest and highest-flying production aircraft. The aircraft can fly at speeds of more than 2,200 miles per hour (Mach 3+, or more than three times the speed of sound) and at altitudes of over 85,000 feet. The Lockheed Skunk Works (now Lockheed Martin) built the original SR-71 aircraft. Each aircraft is 107.4 feet long, has a wingspan of 55.6 feet, and is 18.5 feet high (from the ground to the top of the rudders, when parked). Gross takeoff weight is about 140,000 pounds, including a possible fuel weight of 80,280 pounds. The airframes are built almost entirely of titanium and titanium alloys to withstand heat generated by sustained Mach 3 flight. Aerodynamic control surfaces consist of all-moving vertical tail surfaces, ailerons on the outer wings, and elevators on the trailing edges between the engine exhaust nozzles. The two SR-71s at Dryden have been assigned the following NASA tail numbers: NASA 844 (A model), military serial 61-7980 and NASA 831 (B model), military serial 61-7956. From 1990 through 1994, Dryden also had another 'A' model, NASA 832, military serial 61-7971. This aircraft was returned to the USAF inventory and was the first aircraft reactivated for USAF reconnaissance purposes in 1995. It has since returned to Dryden along with SR-71A 61-79

1999-01-01

152

Instrumentation for measuring aircraft noise and sonic boom  

NASA Technical Reports Server (NTRS)

Improved instrumentation suitable for measuring aircraft noise and sonic booms is described. An electric current proportional to the sound pressure level at a condenser microphone is produced and transmitted over a cable and amplified by a zero drive amplifier. The converter consists of a local oscillator, a dual-gate field-effect transistor mixer, and a voltage regulator/impedance translator. The improvements include automatic tuning compensation against changes in static microphone capacitance and means for providing a remote electrical calibration capability.

Zuckerwar, A. J. (inventor)

1976-01-01

153

Modeled Impact of Cirrus Cloud Increases Along Aircraft Flight Paths  

NASA Technical Reports Server (NTRS)

The potential impact of contrails and alterations in the lifetime of background cirrus due to subsonic airplane water and aerosol emissions has been investigated in a set of experiments using the GISS GCM connected to a q-flux ocean. Cirrus clouds at a height of 12-15km, with an optical thickness of 0.33, were input to the model "x" percentage of clear-sky occasions along subsonic aircraft flight paths, where x is varied from .05% to 6%. Two types of experiments were performed: one with the percentage cirrus cloud increase independent of flight density, as long as a certain minimum density was exceeded; the other with the percentage related to the density of fuel expenditure. The overall climate impact was similar with the two approaches, due to the feedbacks of the climate system. Fifty years were run for eight such experiments, with the following conclusions based on the stable results from years 30-50 for each. The experiments show that adding cirrus to the upper troposphere results in a stabilization of the atmosphere, which leads to some decrease in cloud cover at levels below the insertion altitude. Considering then the total effect on upper level cloud cover (above 5 km altitude), the equilibrium global mean temperature response shows that altering high level clouds by 1% changes the global mean temperature by 0.43C. The response is highly linear (linear correlation coefficient of 0.996) for high cloud cover changes between 0. 1% and 5%. The effect is amplified in the Northern Hemisphere, more so with greater cloud cover change. The temperature effect maximizes around 10 km (at greater than 40C warming with a 4.8% increase in upper level clouds), again more so with greater warming. The high cloud cover change shows the flight path influence most clearly with the smallest warming magnitudes; with greater warming, the model feedbacks introduce a strong tropical response. Similarly, the surface temperature response is dominated by the feedbacks, and shows little geographical relationship to the high cloud input. Considering whether these effects would be observable, changing upper level cloud cover by as little as 0.4% produces warming greater than 2 standard deviations in the Microwave Sounding Unit (MSU) channels 4, 2 and 2r, in flight path regions and in the subtropics. Despite the simplified nature of these experiments, the results emphasize the sensitivity of the modeled climate to high level cloud cover changes, and thus the potential ability of aircraft to influence climate by altering clouds in the upper troposphere.

Rind, David; Lonergan, P.; Shah, K.

1999-01-01

154

Effect of stabilization on VTOL aircraft in hovering flight  

NASA Technical Reports Server (NTRS)

A motion simulator study was conducted to determine the effects of roll and pitch stabilization on the handling qualities and control power requirements of VTOL aircraft during hover and short-distance maneuvering flight. Three levels of stabilization complexity were compared: (1) no stabilization, (2) rate stabilization, and (3) attitude stabilization. Control sensitivities and stabilization gains were optimized prior to comparison. Results are presented to show how the optimum systems were determined and how they compared with each other at different levels of control power. Comparisons were made both in calm air and in the presence of roll disturbances. Results indicate the attitude-stabilized system provides the best handling qualities for the least amount of control power.

Greif, R. K.; Fry, E. B.; Gerdes, R. M.; Gossett, T. D.

1972-01-01

155

Knowledge-based processing for aircraft flight control  

NASA Technical Reports Server (NTRS)

This Contractor Report documents research in Intelligent Control using knowledge-based processing in a manner dual to methods found in the classic stochastic decision, estimation, and control discipline. Such knowledge-based control has also been called Declarative, and Hybid. Software architectures were sought, employing the parallelism inherent in modern object-oriented modeling and programming. The viewpoint adopted was that Intelligent Control employs a class of domain-specific software architectures having features common over a broad variety of implementations, such as management of aircraft flight, power distribution, etc. As much attention was paid to software engineering issues as to artificial intelligence and control issues. This research considered that particular processing methods from the stochastic and knowledge-based worlds are duals, that is, similar in a broad context. They provide architectural design concepts which serve as bridges between the disparate disciplines of decision, estimation, control, and artificial intelligence. This research was applied to the control of a subsonic transport aircraft in the airport terminal area.

Painter, John H.; Glass, Emily; Economides, Gregory; Russell, Paul

1994-01-01

156

Experimental flight test vibration measurements and nondestructive inspection on a USCG HC-130H aircraft  

SciTech Connect

This paper presents results of experimental flight test vibration measurements and structural inspections performed by the Federal Aviation Administration`s Airworthiness Assurance NDI Validation Center (AANC) at Sandia National Laboratories and the US Coast Guard Aircraft Repair and Supply Center (ARSC). Structural and aerodynamic changes induced by mounting a Forward Looking Infrared (FLIR) system on a USCG HC-130H aircraft are described. The FLIR adversely affected the air flow characteristics and structural vibration on the external skin of the aircraft`s right main wheel well fairing. Upon initial discovery of skin cracking and visual observation of skin vibration in flight by the FLIR, a baseline flight without the FLIR was conducted and compared to other measurements with the FLIR installed. Nondestructive inspection procedures were developed to detect cracks in the skin and supporting structural elements and document the initial structural condition of the aircraft. Inspection results and flight test vibration data revealed that the FLIR created higher than expected flight loading and was the possible source of the skin cracking. The Coast Guard performed significant structural repair and enhancement on this aircraft, and additional in-flight vibration measurements were collected on the strengthened area both with and without the FLIR installed. After three months of further operational FLIR usage, the new aircraft skin with the enhanced structural modification was reinspected and found to be free of flaws. Additional US Coast Guard HC-130H aircraft are now being similarly modified to accommodate this FLIR system. Measurements of in-flight vibration levels with and without the FLIR installed, and both before and after the structural enhancement and repair were conducted on the skin and supporting structure in the aircraft`s right main wheel fairing. Inspection results and techniques developed to verify the aircraft`s structural integrity are discussed.

Moore, D.G.; Jones, C.R. [Sandia National Labs., Albuquerque, NM (United States). FAA Airworthiness Assurance NDI Validation Center; Mihelic, J.E.; Barnes, J.D. [Coast Guard Aircraft Repair and Supply Center, Elizabeth City, NC (United States)

1998-08-01

157

SR-71B - in Flight with F-18 Chase Aircraft - View from Air Force Tanker  

NASA Technical Reports Server (NTRS)

NASA 831, an SR-71B operated by the Dryden Flight Research Center, Edwards, California, cruises over the Mojave Desert with an F/A-18 Hornet flying safety chase. They were photographed on a 1996 mission from an Air Force refueling tanker The F/A-18 Hornet is used primarily as a safety chase and support aircraft at Dryden. As support aircraft, the F-18s are used for safety chase, pilot proficiency and aerial photography. Two SR-71 aircraft have been used by NASA as testbeds for high-speed and high-altitude aeronautical research. The aircraft, an SR-71A and an SR-71B pilot trainer aircraft, have been based here at NASA's Dryden Flight Research Center, Edwards, California. They were transferred to NASA after the U.S. Air Force program was cancelled. As research platforms, the aircraft can cruise at Mach 3 for more than one hour. For thermal experiments, this can produce heat soak temperatures of over 600 degrees Fahrenheit (F). This operating environment makes these aircraft excellent platforms to carry out research and experiments in a variety of areas -- aerodynamics, propulsion, structures, thermal protection materials, high-speed and high-temperature instrumentation, atmospheric studies, and sonic boom characterization. The SR-71 was used in a program to study ways of reducing sonic booms or over pressures that are heard on the ground, much like sharp thunderclaps, when an aircraft exceeds the speed of sound. Data from this Sonic Boom Mitigation Study could eventually lead to aircraft designs that would reduce the 'peak' overpressures of sonic booms and minimize the startling affect they produce on the ground. One of the first major experiments to be flown in the NASA SR-71 program was a laser air data collection system. It used laser light instead of air pressure to produce airspeed and attitude reference data, such as angle of attack and sideslip, which are normally obtained with small tubes and vanes extending into the airstream. One of Dryden's SR-71s was used for the Linear Aerospike Rocket Engine, or LASRE Experiment. Another earlier project consisted of a series of flights using the SR-71 as a science camera platform for NASA's Jet Propulsion Laboratory in Pasadena, California. An upward-looking ultraviolet video camera placed in the SR-71's nosebay studied a variety of celestial objects in wavelengths that are blocked to ground-based astronomers. Earlier in its history, Dryden had a decade of past experience at sustained speeds above Mach 3. Two YF-12A aircraft and an SR-71 designated as a YF-12C were flown at the center between December 1969 and November 1979 in a joint NASA/USAF program to learn more about the capabilities and limitations of high-speed, high-altitude flight. The YF-12As were prototypes of a planned interceptor aircraft based on a design that later evolved into the SR-71 reconnaissance aircraft. Dave Lux was the NASA SR-71 project manger for much of the decade of the 1990s, followed by Steve Schmidt. Developed for the USAF as reconnaissance aircraft more than 30 years ago, SR-71s are still the world's fastest and highest-flying production aircraft. The aircraft can fly at speeds of more than 2,200 miles per hour (Mach 3+, or more than three times the speed of sound) and at altitudes of over 85,000 feet. The Lockheed Skunk Works (now Lockheed Martin) built the original SR-71 aircraft. Each aircraft is 107.4 feet long, has a wingspan of 55.6 feet, and is 18.5 feet high (from the ground to the top of the rudders, when parked). Gross takeoff weight is about 140,000 pounds, including a possible fuel weight of 80,280 pounds. The airframes are built almost entirely of titanium and titanium alloys to withstand heat generated by sustained Mach 3 flight. Aerodynamic control surfaces consist of all-moving vertical tail surfaces, ailerons on the outer wings, and elevators on the trailing edges between the engine exhaust nozzles. The two SR-71s at Dryden have been assigned the following NASA tail numbers: NASA 844 (A model), military serial 61-7980 and NASA 831 (B model), military serial 61-7956. From 1990

1996-01-01

158

CID Aircraft in practice flight above target impact site with wing cutters  

NASA Technical Reports Server (NTRS)

In this photograph the B-720 is seen making a practice close approach over the prepared impact site. The wing openers, designed to tear open the wings and spill the fuel, are clearly seen on the ground just at the start of the bed of rocks. In a typical aircraft crash, fuel spilled from ruptured fuel tanks forms a fine mist that can be ignited by a number of sources at the crash site. In 1984 the NASA Dryden Flight Research Facility (after 1994 a full-fledged Center again) and the Federal Aviation Administration (FAA) teamed-up in a unique flight experiment called the Controlled Impact Demonstration (CID), to test crash a Boeing 720 aircraft using standard fuel with an additive designed to supress fire. The additive, FM-9, a high-molecular-weight long-chain polymer, when blended with Jet-A fuel had demonstrated the capability to inhibit ignition and flame propagation of the released fuel in simulated crash tests. This anti-misting kerosene (AMK) cannot be introduced directly into a gas turbine engine due to several possible problems such as clogging of filters. The AMK must be restored to almost Jet-A before being introduced into the engine for burning. This restoration is called 'degradation' and was accomplished on the B-720 using a device called a 'degrader.' Each of the four Pratt & Whitney JT3C-7 engines had a 'degrader' built and installed by General Electric (GE) to break down and return the AMK to near Jet-A quality. In addition to the AMK research the NASA Langley Research Center was involved in a structural loads measurement experiment, which included having instrumented dummies filling the seats in the passenger compartment. Before the final flight on December 1, 1984, more than four years of effort passed trying to set-up final impact conditions considered survivable by the FAA. During those years while 14 flights with crews were flown the following major efforts were underway: NASA Dryden developed the remote piloting techniques necessary for the B-720 to fly as a drone aircraft; General Electric installed and tested four degraders (one on each engine); and the FAA refined AMK (blending, testing, and fueling a full-size aircraft). The 15 flights had 15 takeoffs, 14 landings and a larger number of approaches to about 150 feet above the prepared crash site under remote control. These flight were used to introduce AMK one step at a time into some of the fuel tanks and engines while monitoring the performance of the engines. On the final flight (No. 15) with no crew, all fuel tanks were filled with a total of 76,000 pounds of AMK and the remotely-piloted aircraft landed on Rogers Dry Lakebed in an area prepared with posts to test the effectiveness of the AMK in a controlled impact. The CID, which some wags called the Crash in the Desert, was spectacular with a large fireball enveloping and burning the B-720 aircraft. From the standpoint of AMK the test was a major set-back, but for NASA Langley, the data collected on crashworthiness was deemed successful and just as important.

1984-01-01

159

Measurements of carbon monoxide, condensation nuclei, and ozone on a B 747SP aircraft flight around the world  

NASA Technical Reports Server (NTRS)

Measurements of carbon monoxide, condensation nuclei, and ozone concentrations were obtained during a 54 hour polar flight around the world by an automated instrument package carried by a B-747SP commercial aircraft. These and other data were obtained as part of the NASA Global Atmospheric Sampling Program. All data exhibited longitudinal and hemispheric differences. Analysis of the data indicate increased concentrations of carbon monoxide and condensation nuclei at flight levels in the troposphere over tropical land masses. A background concentration for condensation nuclei was found to be 200 per cu cm for tropical tropospheric maritime air.

Gauntner, D. J.; Nyland, T.; Tiefermann, M.; Dudzinski, T.

1979-01-01

160

Analysis and Monte Carlo simulation of near-terminal aircraft flight paths  

NASA Technical Reports Server (NTRS)

The flight paths of arriving and departing aircraft at an airport are stochastically represented. Radar data of the aircraft movements are used to decompose the flight paths into linear and curvilinear segments. Variables which describe the segments are derived, and the best fitting probability distributions of the variables, based on a sample of flight paths, are found. Conversely, given information on the probability distribution of the variables, generation of a random sample of flight paths in a Monte Carlo simulation is discussed. Actual flight paths at Dulles International Airport are analyzed and simulated.

Schiess, J. R.; Matthews, C. G.

1982-01-01

161

Instrumentation for In-Flight SSME Rocket Engine Plume Spectroscopy  

NASA Technical Reports Server (NTRS)

This paper describes instrumentation that is under development for an in-flight demonstration of a plume spectroscopy system on the space shuttle main engine. The instrumentation consists of a nozzle mounted optical probe for observation of the plume, and a spectrometer for identification and quantification of plume content. This instrumentation, which is intended for use as a diagnostic tool to detect wear and incipient failure in rocket engines, will be validated by a hardware demonstration on the Technology Test Bed engine at the Marshall Space Flight Center.

Madzsar, George C.; Bickford, Randall L.; Duncan, David B.

1994-01-01

162

Instrumentation for in-flight SSME rocket engine plume spectroscopy  

NASA Astrophysics Data System (ADS)

This paper describes instrumentation that is under development for an in-flight demonstration of a plume spectroscopy system on the space shuttle main engine. The instrumentation consists of a nozzle mounted optical probe for observation of the plume, and a spectrometer for identification and quantification of plume content. This instrumentation, which is intended for use as a diagnostic tool to detect wear and incipient failure in rocket engines, will be validated by a hardware demonstration on the Technology Test Bed engine at the Marshall Space Flight Center.

Madzsar, George C.; Bickford, Randall L.; Duncan, David B.

1994-06-01

163

Aeroacoustics: Acoustic wave propagation; Aircraft noise prediction; Aeroacoustic instrumentation  

NASA Technical Reports Server (NTRS)

The papers in this volume deal with recent research into acoustic-wave propagation through the atmosphere and progress in aeroacoustic instrumentation, facilities, and test techniques. Topics include the propagation of aircraft noise over long distances in the lower atmosphere, measured effects of turbulence on the rise time of a weak shock, sound scattering from atmospheric turbulence, saturation effects associated with sound propagation in a turbulent medium, and a computer model of the lightning-thunder process. Other papers discuss the development of a computer system for aircraft noise prediction; aircraft flyover noise measurements; and theories and methods for the prediction of ground effects on aircraft noise propagation, for the prediction of airframe aerodynamic noise, for turbine noise prediction, and for combustion noise prediction. Attention is also given to the use of Hartmann generators as sources of high-intensity sound in a large absorption flow-duct facility, an outdoor jet noise facility, factors in the design and performance of free-jet acoustic wind tunnels, and the use of a laser shadowgraph for jet noise diagnosis.

Schwartz, I. R.

1976-01-01

164

VISUAL FLIGHT RULES (VFR) FLIGHT INTO INSTRUMENT METEOROLOGICAL CONDITIONS (IMC): A REVIEW OF THE ACCIDENT DATA  

Microsoft Academic Search

General Aviation (GA) accident statistics indicate that visual flight rules (VFR) flight into instrument meteorological conditions (IMC) is a major safety hazard within general aviation. Little research has been conducted to identify the factors that influence VFR pilots' decisions to risk flying into deteriorating weather. As accident reports provide a naturalistic source of such information, this paper presents an analysis

Juliana Goh; Douglas Wiegmann

165

Basic principles of flight test instrumentation engineering, volume 1, issue 2  

NASA Technical Reports Server (NTRS)

Volume 1 of the AG 300 series on 'Flight Test Instrumentation' gives a general introduction to the basic principles of flight test instrumentation. The other volumes in the series provide more detailed treatments of selected topics on flight test instrumentation. Volume 1, first published in 1974, has been used extensively as an introduction for instrumentation courses and symposia, as well as being a reference work on the desk of most flight test and instrumentation engineers. It is hoped that this second edition, fully revised, will be used with as much enthusiasm as the first edition. In this edition a flight test system is considered to include both the data collection and data processing systems. In order to obtain an optimal data flow, the overall design of these two subsystems must be carefully matched; the detail development and the operation may have to be done by separate groups of specialists. The main emphasis is on the large automated instrumentation systems used for the initial flight testing of modern military and civil aircraft. This is done because there, many of the problems, which are discussed here, are more critical. It does not imply, however, that smaller systems with manual data processing are no longer used. In general, the systems should be designed to provide the required results at the lowest possible cost. For many tests which require only a few parameters, relatively simple systems are justified, especially if no complex equipment is available to the user. Although many of the aspects discussed in this volume apply to both small and large systems, aspects of the smaller systems are mentioned only when they are of special interest. The volume has been divided into three main parts. Part 1 defines the main starting points for the design of a flight test instrumentation system, as seen from the points of view of the flight test engineer and the instrumentation engineer. In Part 2 the discussion is concentrated on those aspects which apply to each individual measuring channel, and in Part 3 the main emphasis is on the integration of the individual data channels into one data collection system and on those aspects of the data processing which apply to the complete system.

Borek, Robert W., Sr. (editor); Pool, A. (editor)

1994-01-01

166

Flow energizer flight tests on a light twin aircraft  

NASA Technical Reports Server (NTRS)

Experiments were conducted to explore the use of flow energizers (i.e., horizontally mounted vortex generators), using a special instrumentation subsystem installed on a light twin aircraft. The data, collected for energizer configurations with convergence ratios of 1.2, 1.5, and 1.7, included measurements of pressure on the wing surface, velocity components in the wake of the energizer, and forces on the flow energizer itself. Surface pressure data showed that flow energizer effects are highly localized. The energizer with the smallest convergence ratio tested produced an energizer lift/drag ratio about 75 percent lower that that of the other two configurations. For highly swept planforms, cambered energizers with overlaps of the order of 12-15 percent of the local chord provide the best results.

Ward, D. T.; Pradhan, A. A.; Binford, R. S.

1987-01-01

167

Aircraft motion and passenger comfort response data from TIFS ride-quality flight experiments  

NASA Technical Reports Server (NTRS)

The aircraft motion data and passenger comfort response data obtained during ride-quality flight experiments using the USAD Total In-Flight Simulator (TIFS) are given. During each of 40 test flights, 10 passenger subjects individually assessed the ride comfort of various types of aircraft motions. The 115 individuals who served as passenger subjects were selected to be representative of air travelers in general. Aircraft motions tested consisted of both random and sinusoidal oscillations in various combinations of five degrees of freedom (transverse, normal, roll, pitch, and yaw), as well as of terminal-area flight maneuvers. The data are sufficiently detailed to allow analysis of passenger reactions to flight environments, evaluation of the use of a portable environment measuring/recording system and comparison of the in-flight simulator responses with input commands.

Schoonover, W. E., Jr.

1976-01-01

168

A review of in-flight detection and identification of aircraft icing and reconfigurable control  

NASA Astrophysics Data System (ADS)

The recent improvements and research on aviation have focused on the subject of aircraft safe flight even in the severe weather conditions. As one type of such weather conditions, aircraft icing considerably has negative effects on the aircraft flight performance. The risks of the iced aerodynamic surfaces of the flying aircraft have been known since the beginning of the first flights. Until recent years, as a solution for this event, the icing conditions ahead flight route are estimated from radars or other environmental sensors, hence flight paths are changed, or, if it exists, anti-icing/de-icing systems are used. This work aims at the detection and identification of airframe icing based on statistical properties of aircraft dynamics and reconfigurable control protecting aircraft from hazardous icing conditions. In this review paper, aircraft icing identification based on neural network (NN), batch least-squares algorithm, Kalman filtering (KF), combined NN/KF, and H? parameter identification techniques are investigated, and compared with each other. Following icing identification, reconfigurable control is applied for protecting the aircraft from hazardous icing conditions.

Caliskan, Fikret; Hajiyev, Chingiz

2013-07-01

169

Dispersion and dilution of jet aircraft exhaust at high-altitude flight conditions  

NASA Technical Reports Server (NTRS)

A method is presented for estimating the dispersion and dilution of jet aircraft exhaust from aircraft passage through times on the order of weeks thereafter. In the near wake of the aircraft, the solution is that for round turbulent jets in a parallel flow. More rapid dispersion due to atmospheric effects begins when the scale-dependent eddy viscosity becomes larger than the turbulent jet eddy viscosity. In the far wake region, the solution approaches that for scale-dependent dispersion from a point source moving with the aircraft. Calculations are presented for supersonic aircraft at high altitude flight conditions.

Holdeman, J. D.

1973-01-01

170

Flight test of ARINC 741 configuration low gain SATCOM system on Boeing 747-400 aircraft  

NASA Technical Reports Server (NTRS)

The Boeing company conducted a flight test of a SATCOM system similar to the ARINC 741 configuration on a production model 747-400. A flight plan was specifically designed to test the system over a wide variety of satellite elevations and aircraft attitudes as well as over land and sea. Interface bit errors, signal quality and aircraft position and navigational inputs were all recorded as a function of time. Special aircraft maneuvers were performed to demonstrate the potential for shadowing by aircraft structures. Both a compass rose test and the flight test indicated that shadowing from the tail is insignificant for the 747-400. However, satellite elevation angles below the aircraft horizon during banking maneuvers were shown to have a significant deleterious effect on SATCOM communications.

Murphy, Timothy A.; Stapleton, Brian P.

1990-01-01

171

Instrumentation for space flight experiments. [using nonhuman primates  

NASA Technical Reports Server (NTRS)

The selection of measurement systems for experiments conducted in the context of a space flight must be guided by the criteria applicable to any scientific study requiring objective measurements of physiological variables. Steps fundamental to the process of choosing the best instrumentation system are identified and the key factors in matching the operational characteristics of the instrumentation to its intended use are discussed. Special problems in obtaining data from nonhuman primates, whether restrained or unrestrained, are explored. Choices for data processing are evaluated as well as the use of prototype flight tests and simulations to assess future life science experiments for spacelab or payloads for the space shuttle biomedical scientific satellite.

Mccutcheon, E. P.

1977-01-01

172

Dynamic ground effects flight test of an F-15 aircraft  

NASA Technical Reports Server (NTRS)

Flight tests to determine the changes in the aerodynamic characteristics of an F-15 aircraft caused by dynamic ground effects are described. Data were obtained for low and high sink rates between 0.7 and 6.5 ft/sec and at two landing approach speeds and flap settings: 150 kn with the flaps down and 170 kn with the flaps up. Simple correlation curves are given for the change in aerodynamic coefficients because of ground effects as a function of sink rate. Ground effects generally caused an increase in the lift, drag, and nose-down pitching movement coefficients. The change in the lift coefficient increased from approximately 0.05 at the high-sink rate to approximately 0.10 at the low-sink rate. The change in the drag coefficient increased from approximately 0 to 0.03 over this decreasing sink rate range. No significant difference because of the approach configuration was evident for lift and drag; however, a significant difference in pitching movement was observed for the two approach speeds and flap settings. For the 170 kn with the flaps up configuration, the change in the nose-down pitching movement increased from approximately -0.008 to -0.016. For the 150 kn with the flaps down configuration, the change was approximately -0.008 to -0.038.

Corda, Stephen; Stephenson, Mark T.; Burcham, Frank W.; Curry, Robert E.

1994-01-01

173

Use of eternal flight unmanned aircraft in military operations  

NASA Astrophysics Data System (ADS)

Unmanned Aerial Vehicles (UAV), are planned to use solar energy, are being more common and interesting gradually. Today, these systems are very promising while fossil fuels are diminishing rapidly. Academic research is still being conducted to develop unmanned aerial systems which will store energy during day time and use it during night time. Development of unmanned aerial systems, which have eternal flight or very long loiter periods, could be possible by such an energy management. A UAV, which can fly very long time, could provide many advantages that cannot be obtained by conventional aircrafts and satellites. Such systems can be operated as fixed satellites on missions with very low cost in circumstances that require continuous intelligence. By improving automation systems these vehicles could be settled on operation area autonomously and can be grounded easily in case of necessities and maintenance. In this article, the effect of solar powered UAV on operation area has been done a literature review, to be used in surveillance and reconnaissance missions.

Kök, Zafer

2014-06-01

174

AIRCRAFT TIME-2D LONGITUDINAL GUIDANCE BASED ON SPATIAL INVERSION OF FLIGHT DYNAMICS  

E-print Network

AIRCRAFT TIME-2D LONGITUDINAL GUIDANCE BASED ON SPATIAL INVERSION OF FLIGHT DYNAMICS Hakim Bouadi, Netherlands Abstract With the growth of civil aviation traffic capacity, safety and environmental with real time corrective actions to maintain the aircraft trajectory as close as possible to the planned

Boyer, Edmond

175

Prepared by: Shawn Coyle, Aircraft Certification, Flight Test. Transport Canada, Ottawa, Ontario.  

E-print Network

Prepared by: Shawn Coyle, Aircraft Certification, Flight Test. Transport Canada, Ottawa, Ontario. ph 613 954 1390, fax 613 996 9178, e-mail CoyleS@tc.gc.ca Aircraft On-Board Navigation Data Integrity A Serious Problem Transport Canada Database Working Group Paper Transport Canada Transports Canada Safety

Ladkin, Peter B.

176

Energy efficient engine flight propulsion system: Aircraft/engine integration evaluation  

NASA Technical Reports Server (NTRS)

Results of aircraft/engine integration studies conducted on an advanced flight propulsion system are reported. Economic evaluations of the preliminary design are included and indicate that program goals will be met. Installed sfc, DOC, noise, and emissions were evaluated. Aircraft installation considerations and growth were reviewed.

Patt, R. F.

1980-01-01

177

Aircraft interrogation and display system: A ground support equipment for digital flight systems  

NASA Technical Reports Server (NTRS)

A microprocessor-based general purpose ground support equipment for electronic systems was developed. The hardware and software are designed to permit diverse applications in support of aircraft flight systems and simulation facilities. The implementation of the hardware, the structure of the software, describes the application of the system to an ongoing research aircraft project are described.

Glover, R. D.

1982-01-01

178

Flight testing of a reconfigurable control system on an unmanned aircraft  

Microsoft Academic Search

A radio-controlled aircraft was built and equipped with air-data and inertial sensors. A radio frequency link was added to transmit data and receive commands from a ground station. Data from several flight tests were used to characterize the dynamic response of the aircraft. Despite the high level of noise associated with the low-cost sensor suite, consistent identification of critical aircraft

David Shore; Marc Bodson

2004-01-01

179

Flight Dynamics of Flexible Aircraft with Aeroelastic and Inertial Force Interactions  

NASA Technical Reports Server (NTRS)

This paper presents an integrated flight dynamic modeling method for flexible aircraft that captures coupled physics effects due to inertial forces, aeroelasticity, and propulsive forces that are normally present in flight. The present approach formulates the coupled flight dynamics using a structural dynamic modeling method that describes the elasticity of a flexible, twisted, swept wing using an equivalent beam-rod model. The structural dynamic model allows for three types of wing elastic motion: flapwise bending, chordwise bending, and torsion. Inertial force coupling with the wing elasticity is formulated to account for aircraft acceleration. The structural deflections create an effective aeroelastic angle of attack that affects the rigid-body motion of flexible aircraft. The aeroelastic effect contributes to aerodynamic damping forces that can influence aerodynamic stability. For wing-mounted engines, wing flexibility can cause the propulsive forces and moments to couple with the wing elastic motion. The integrated flight dynamics for a flexible aircraft are formulated by including generalized coordinate variables associated with the aeroelastic-propulsive forces and moments in the standard state-space form for six degree-of-freedom flight dynamics. A computational structural model for a generic transport aircraft has been created. The eigenvalue analysis is performed to compute aeroelastic frequencies and aerodynamic damping. The results will be used to construct an integrated flight dynamic model of a flexible generic transport aircraft.

Nguyen, Nhan T.; Tuzcu, Ilhan

2009-01-01

180

A Perspective on Development Flight Instrumentation and Flight Test Analysis Plans for Ares I-X  

NASA Technical Reports Server (NTRS)

NASA. s Constellation Program will take a significant step toward completion of the Ares I crew launch vehicle with the flight test of Ares I-X and completion of the Ares I-X post-flight evaluation. The Ares I-X flight test vehicle is an ascent development flight test that will acquire flight data early enough to impact the design and development of the Ares I. As the primary customer for flight data from the Ares I-X mission, Ares I has been the major driver in the definition of the Development Flight Instrumentation (DFI). This paper focuses on the DFI development process and the plans for post-flight evaluation of the resulting data to impact the Ares I design. Efforts for determining the DFI for Ares I-X began in the fall of 2005, and significant effort to refine and implement the Ares I-X DFI has been expended since that time. This paper will present a perspective in the development and implementation of the DFI. Emphasis will be placed on the process by which the list was established and changes were made to that list due to imposed constraints. The paper will also discuss the plans for the analysis of the DFI data following the flight and a summary of flight evaluation tasks to be performed in support of tools and models validation for design and development.

Huebner, Lawrence D.; Richards, James S.; Brunty, Joseph A.; Smith, R. Marshall; Trombetta, Dominic R.

2009-01-01

181

Development of control laws for a flight test maneuver autopilot for an F-15 aircraft  

NASA Technical Reports Server (NTRS)

An autopilot can be used to provide precise control to meet the demanding requirements of flight research maneuvers with high-performance aircraft. This paper presents the development of control laws within the context of flight test maneuver requirements. The control laws are developed using eigensystem assignment and command generator tracking. The eigenvalues and eigenvectors are chosen to provide the necessary handling qualities, while the command generator tracking enables the tracking of a specified state during the maneuver. The effectiveness of the control laws is illustrated by their application to an F-15 aircraft to ensure acceptable aircraft performance during a maneuver.

Alag, G. S.; Duke, E. L.

1985-01-01

182

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

NASA Technical Reports Server (NTRS)

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.

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

2008-01-01

183

Design of Flight Control System for a Small Unmanned Tilt Rotor Aircraft  

Microsoft Academic Search

A tilt rotor is an aircraft of a special kind, which possesses the characteristics of a helicopter and a fixed-wing airplane. However, there are a great number of important technical problems waiting for settlements. Of them, the flight control system might be a critical one. This article presents the progresses of the research work on the design of flight control

Song Yanguo; Wang Huanjin

2009-01-01

184

Scaled Measurements of Instrument-Landing-System Disturbances Due to Large Taxiing Aircraft  

Microsoft Academic Search

It is commonly known that the directional pattern of the instrument landing system (ILS)-localizer antenna system, which constitutes the landing-course information for approaching aircraft, can be disturbed by reflections from large aircraft on the ground. Therefore, airport operators are interested in knowing configurations of landed and taxiing aircraft that lead to such ILS disturbance scenarios. Measurements on a real airport

Robert Geise; Achim Enders; Helge Vahle; Harald Spieker

2008-01-01

185

Launch Vehicle Manual Steering with Adaptive Augmenting Control In-flight Evaluations Using a Piloted Aircraft  

NASA Technical Reports Server (NTRS)

An adaptive augmenting control algorithm for the Space Launch System has been developed at the Marshall Space Flight Center as part of the launch vehicles baseline flight control system. A prototype version of the SLS flight control software was hosted on a piloted aircraft at the Armstrong Flight Research Center to demonstrate the adaptive controller on a full-scale realistic application in a relevant flight environment. Concerns regarding adverse interactions between the adaptive controller and a proposed manual steering mode were investigated by giving the pilot trajectory deviation cues and pitch rate command authority.

Hanson, Curt

2014-01-01

186

A knowledge-based system design/information tool for aircraft flight control systems  

NASA Technical Reports Server (NTRS)

Research aircraft have become increasingly dependent on advanced electronic control systems to accomplish program goals. These aircraft are integrating multiple disciplines to improve performance and satisfy research objective. This integration is being accomplished through electronic control systems. Systems design methods and information management have become essential to program success. The primary objective of the system design/information tool for aircraft flight control is to help transfer flight control system design knowledge to the flight test community. By providing all of the design information and covering multiple disciplines in a structured, graphical manner, flight control systems can more easily be understood by the test engineers. This will provide the engineers with the information needed to thoroughly ground test the system and thereby reduce the likelihood of serious design errors surfacing in flight. The secondary object is to apply structured design techniques to all of the design domains. By using the techniques in the top level system design down through the detailed hardware and software designs, it is hoped that fewer design anomalies will result. The flight test experiences are reviewed of three highly complex, integrated aircraft programs: the X-29 forward swept wing; the advanced fighter technology integration (AFTI) F-16; and the highly maneuverable aircraft technology (HiMAT) program. Significant operating technologies, and the design errors which cause them, is examined to help identify what functions a system design/informatin tool should provide to assist designers in avoiding errors.

Mackall, Dale A.; Allen, James G.

1991-01-01

187

A knowledge-based system design/information tool for aircraft flight control systems  

NASA Technical Reports Server (NTRS)

Research aircraft have become increasingly dependent on advanced control systems to accomplish program goals. These aircraft are integrating multiple disciplines to improve performance and satisfy research objectives. This integration is being accomplished through electronic control systems. Because of the number of systems involved and the variety of engineering disciplines, systems design methods and information management have become essential to program success. The primary objective of the system design/information tool for aircraft flight control system is to help transfer flight control system design knowledge to the flight test community. By providing all of the design information and covering multiple disciplines in a structured, graphical manner, flight control systems can more easily be understood by the test engineers. This will provide the engineers with the information needed to thoroughly ground test the system and thereby reduce the likelihood of serious design errors surfacing in flight. The secondary objective is to apply structured design techniques to all of the design domains. By using the techniques in the top level system design down through the detailed hardware and software designs, it is hoped that fewer design anomalies will result. The flight test experiences of three highly complex, integrated aircraft programs are reviewed: the X-29 forward-swept wing, the advanced fighter technology integration (AFTI) F-16, and the highly maneuverable aircraft technology (HiMAT) program. Significant operating anomalies and the design errors which cause them, are examined to help identify what functions a system design/information tool should provide to assist designers in avoiding errors.

Mackall, Dale A.; Allen, James G.

1989-01-01

188

Aircraft signal definition for flight safety system monitoring system  

NASA Technical Reports Server (NTRS)

A system and method compares combinations of vehicle variable values against known combinations of potentially dangerous vehicle input signal values. Alarms and error messages are selectively generated based on such comparisons. An aircraft signal definition is provided to enable definition and monitoring of sets of aircraft input signals to customize such signals for different aircraft. The input signals are compared against known combinations of potentially dangerous values by operational software and hardware of a monitoring function. The aircraft signal definition is created using a text editor or custom application. A compiler receives the aircraft signal definition to generate a binary file that comprises the definition of all the input signals used by the monitoring function. The binary file also contains logic that specifies how the inputs are to be interpreted. The file is then loaded into the monitor function, where it is validated and used to continuously monitor the condition of the aircraft.

Gibbs, Michael (Inventor); Omen, Debi Van (Inventor)

2003-01-01

189

A Risk Assessment Model for Reduced Aircraft Separation: A Quantitative Method to Evaluate the Safety of Free Flight  

NASA Technical Reports Server (NTRS)

As new technologies and procedures are introduced into the National Airspace System, whether they are intended to improve efficiency, capacity, or safety level, the quantification of potential changes in safety levels is of vital concern. Applications of technology can improve safety levels and allow the reduction of separation standards. An excellent example is the Precision Runway Monitor (PRM). By taking advantage of the surveillance and display advances of PRM, airports can run instrument parallel approaches to runways separated by 3400 feet with the same level of safety as parallel approaches to runways separated by 4300 feet using the standard technology. Despite a wealth of information from flight operations and testing programs, there is no readily quantifiable relationship between numerical safety levels and the separation standards that apply to aircraft on final approach. This paper presents a modeling approach to quantify the risk associated with reducing separation on final approach. Reducing aircraft separation, both laterally and longitudinally, has been the goal of several aviation R&D programs over the past several years. Many of these programs have focused on technological solutions to improve navigation accuracy, surveillance accuracy, aircraft situational awareness, controller situational awareness, and other technical and operational factors that are vital to maintaining flight safety. The risk assessment model relates different types of potential aircraft accidents and incidents and their contribution to overall accident risk. The framework links accident risks to a hierarchy of failsafe mechanisms characterized by procedures and interventions. The model will be used to assess the overall level of safety associated with reducing separation standards and the introduction of new technology and procedures, as envisaged under the Free Flight concept. The model framework can be applied to various aircraft scenarios, including parallel and in-trail approaches. This research was performed under contract to NASA and in cooperation with the FAA's Safety Division (ASY).

Cassell, Rick; Smith, Alex; Connors, Mary; Wojciech, Jack; Rosekind, Mark R. (Technical Monitor)

1996-01-01

190

Design of fine attitude flight control for a highspeed test aircraft  

Microsoft Academic Search

The ramjet is a new type propulsion system for high-speed flight test aircraft. The ultimate success of sustained high-speed flight will depend on configuring a fine and stable attitude flight control and robust airframe-propulsion-control combination. The mathematical models of high-speed aerodynamic forces and moments were established. A bank-to-turn autopilot structure was used for the longitudinal motion and lateral motion study.

Xin Wang

2009-01-01

191

Flight simulator experiments to determine human reaction to aircraft motion environments  

NASA Technical Reports Server (NTRS)

An analysis of human response to aircraft motion is presented using data obtained on the NASA Flight Research Center's Jetstar aircraft. The purpose of these tests was to explore the relationship of vertical and transverse accelerations to human comfort as well as obtain information on the maximum comfortable bank angle for commercial aircraft operations. A preliminary study was also conducted to establish the importance or lack thereof of the low frequency content of aircraft motion due to natural turbulence. An effort has been made to model these data and comparisons with appropriate sources are made.

Jacobson, I. D.; Rudrapatna, A. N.

1974-01-01

192

Analytical design and simulation evaluation of an approach flight director system for a jet STOL aircraft  

NASA Technical Reports Server (NTRS)

A program was undertaken to develop design criteria and operational procedures for STOL transport aircraft. As part of that program, a series of flight tests shall be performed in an Augmentor Wing Jet STOL Aircraft. In preparation for the flight test programs, an analytical study was conducted to gain an understanding of the characteristics of the vehicle for manual control, to assess the relative merits of the variety of manual control techniques available with attitude and thrust vector controllers, and to determine what improvements can be made over manual control of the bare airframe by providing the pilot with suitable command guidance information and by augmentation of the bare airframe dynamics. The objective of the study is to apply closed-loop pilot/vehicle analysis techniques to the analysis of manual flight control of powered-lift STOL aircraft in the landing approach and to the design and experimental verification of an advanced flight director display.

Klein, R. H.; Hofmann, L. G.; Mcruer, D. T.

1974-01-01

193

Acoustic flight testing of advanced design propellers on a JetStar aircraft  

NASA Technical Reports Server (NTRS)

Advanced turboprop-powered aircraft have the potential to reduce fuel consumption by 15 to 30 percent as compared with an equivalent technology turbofan-powered aircraft. An important obstacle to the use of advanced design propellers is the cabin noise generated at Mach numbers up to .8 and at altitudes up to 35,000 feet. As part of the NASA Aircraft Energy Efficiency Program, the near-field acoustic characteristics on a series of advanced design propellers are investigated. Currently, Dryden Flight Research Center is flight testing a series of propellers on a JetStar airplane. The propellers used in the flight test were previously tested in wind tunnels at the Lewis Research Center. Data are presented showing the narrow band spectra, acoustic wave form, and acoustic contours on the fuselage surface. Additional flights with the SR-3 propeller and other advanced propellers are planned in the future.

Lasagna, P.; Mackall, K.

1981-01-01

194

Results of the recent precipitation static flight test program on the Navy P-3B antisubmarine aircraft  

NASA Technical Reports Server (NTRS)

Severe precipitation static problems affecting the communication equipment onboard the P-3B aircraft were recently studied. The study was conducted after precipitation static created potential safety-of-flight problems on Naval Reserve aircraft. A specially designed flight test program was conducted in order to measure, record, analyze, and characterize potential precipitation static problem areas. The test program successfully characterized the precipitation static interference problems while the P-3B was flown in moderate to extreme precipitation conditions. Data up to 400 MHz were collected on the effects of engine charging, precipitation static, and extreme cross fields. These data were collected using a computer controlled acquisition system consisting of a signal generator, RF spectrum and audio analyzers, data recorders, and instrumented static dischargers. The test program is outlined and the computer controlled data acquisition system is described in detail which was used during flight and ground testing. The correlation of test results is also discussed which were recorded during the flight test program and those measured during ground testing.

Whitaker, Mike

1991-01-01

195

Meteorological and operational aspects of 46 clear air turbulence sampling missions with an instrument B-57B aircraft. Volume 1: Program summary  

NASA Technical Reports Server (NTRS)

The results of 46 clear air turbulence (CAT) probing missions conducted with an extensively instrumented B-57B aircraft are summarized. Turbulence samples were obtained under diverse conditions including mountain waves, jet streams, upper level fronts and troughs, and low altitude mechanical and thermal turbulence. CAT was encouraged on 20 flights comprising 77 data runs. In all, approximately 4335 km were flown in light turbulence, 1415 km in moderate turbulence, and 255 km in severe turbulence during the program. The flight planning, operations, and turbulence forecasting aspects conducted with the B-57B aircraft are presented.

Davis, R. E.; Champine, R. A.; Ehernberger, L. J.

1979-01-01

196

A Simplified Instrument for Recording and Indicating Frequency and Intensity of Icing Conditions Encountered in Flight  

NASA Technical Reports Server (NTRS)

An instrument for recording and indicating the frequency and intensity of aircraft icing conditions encountered in flight has been developed by the NACA Lewis Laboratory to obtain statistical icing data over world-wide air routes during routine airline operations. The operation of the instrument is based on the creation of a differential pressure between an ice-free total-pressure system and a total-pressure system in which small total-pressure holes vented to static pressure are allowed to plug with ice accretion. The simplicity of this operating principle permits automatic operation, and provides relative freedom from maintenance and operating problems. The complete unit weighing only 18 pounds records icing rate, airspeed, and altitude on photographic film and provides visual indications of icing intensity to the pilot.

Perkins, Porter J; Mccullough, Stuart; Lewis, Ralph D

1951-01-01

197

Aircraft Flight Envelope Determination using Upset Detection and Physical Modeling Methods  

NASA Technical Reports Server (NTRS)

The development of flight control systems to enhance aircraft safety during periods of vehicle impairment or degraded operations has been the focus of extensive work in recent years. Conditions adversely affecting aircraft flight operations and safety may result from a number of causes, including environmental disturbances, degraded flight operations, and aerodynamic upsets. To enhance the effectiveness of adaptive and envelope limiting controls systems, it is desirable to examine methods for identifying the occurrence of anomalous conditions and for assessing the impact of these conditions on the aircraft operational limits. This paper describes initial work performed toward this end, examining the use of fault detection methods applied to the aircraft for aerodynamic performance degradation identification and model-based methods for envelope prediction. Results are presented in which a model-based fault detection filter is applied to the identification of aircraft control surface and stall departure failures/upsets. This application is supported by a distributed loading aerodynamics formulation for the flight dynamics system reference model. Extensions for estimating the flight envelope due to generalized aerodynamic performance degradation are also described.

Keller, Jeffrey D.; McKillip, Robert M. Jr.; Kim, Singwan

2009-01-01

198

Shuttle flight pressure instrumentation: Experience and lessons for the future  

NASA Technical Reports Server (NTRS)

Flight data obtained from the Space Transportation System orbiter entries are processed and analyzed to assess the accuracy and performance of the Development Flight Instrumentation (DFI) pressure measurement system. Selected pressure measurements are compared with available wind tunnel and computational data and are further used to perform air data analyses using the Shuttle Entry Air Data System (SEADS) computation technique. The results are compared to air data from other sources. These comparisons isolate and demonstrate the effects of the various limitations of the DFI pressure measurement system. The effects of these limitations on orbiter performance analyses are addressed, and instrumentation modifications are recommended to improve the accuracy of similar fight data systems in the future.

Siemers, P. M., III; Bradley, P. F.; Wolf, H.; Flanagan, P. F.; Weilmuenster, K. J.; Kern, F. A.

1983-01-01

199

Pathfinder aircraft liftoff on altitude record setting flight of 71,500 feet  

NASA Technical Reports Server (NTRS)

The Pathfinder aircraft has set a new unofficial world record for high-altitude flight of over 71,500 feet for solar-powered aircraft at the U.S. Navy's Pacific Missile Range Facility, Kauai, Hawaii. Pathfinder was designed and manufactured by AeroVironment, Inc, of Simi Valley, California, and was operated by the firm under a jointly sponsored research agreement with NASA's Dryden Flight Research Center, Edwards, California. Pathfinder's record-breaking flight occurred July 7, 1997. The aircraft took off at 11:34 a.m. PDT, passed its previous record altitude of 67,350 feet at about 5:45 p.m. and then reached its new record altitude at 7 p.m. The mission ended with a perfect nighttime landing at 2:05 a.m. PDT July 8. The new record is the highest altitude ever attained by a propellor-driven aircraft. Before Pathfinder, the altitude record for propellor-driven aircraft was 67,028 feet, set by the experimental Boeing Condor remotely piloted aircraft. Pathfinder was a lightweight, solar-powered, remotely piloted flying wing aircraft used to demonstrate the use of solar power for long-duration, high-altitude flight. Its name denotes its mission as the 'Pathfinder' or first in a series of solar-powered aircraft that will be able to remain airborne for weeks or months on scientific sampling and imaging missions. Solar arrays covered most of the upper wing surface of the Pathfinder aircraft. These arrays provided up to 8,000 watts of power at high noon on a clear summer day. That power fed the aircraft's six electric motors as well as its avionics, communications, and other electrical systems. Pathfinder also had a backup battery system that could provide power for two to five hours, allowing for limited-duration flight after dark. Pathfinder flew at airspeeds of only 15 to 20 mph. Pitch control was maintained by using tiny elevators on the trailing edge of the wing while turns and yaw control were accomplished by slowing down or speeding up the motors on the outboard sections of the wing. On September 11, 1995, Pathfinder set a new altitude record for solar-powered aircraft of 50,567 feet above Edwards Air Force Base, California, on a 12-hour flight. On July 7, 1997, it set another, unofficial record of 71,500 feet at the Pacific Missile Range Facility, Kauai, Hawaii. In 1998, Pathfinder was modified into the longer-winged Pathfinder Plus configuration. (See the Pathfinder Plus photos and project description.)

1997-01-01

200

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)

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.

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

2001-01-01

201

Flight test and evaluation of Omega navigation in a general aviation aircraft. Volume 1: Technical  

NASA Technical Reports Server (NTRS)

A low cost flight research program was conducted to evaluate the performance of differential Omega navigation in a general aviation aircraft. The flight program consisted of two distinct parts corresponding to the two major objectives of the study. The Wallops Flight Program was conducted to obtain Omega signal and phase data in the Wallops Flight Center vicinity to provide preliminary technical information and experience in preparation for a comprehensive NASA/FAA flight test program of an experimental differential Omega system. The Northeast Corridor Flight Program was conducted to examine Omega operational suitability and performance on low altitude area navigation (RNAV) routes for city-center to city-center VTOL commercial operations in the Boston-New York-Washington corridor. The development, execution and conclusions of the flight research program are discribed. The results of the study provide both quantitative and qualitative data on the Omega Navigation System under actual operating conditions.

Howell, J. D.; Hoffman, W. C.; Hwoschinsky, P. V.; Wischmeyer, C. E.

1975-01-01

202

Robotics and Automation for Flight Deck Aircraft Servicing  

SciTech Connect

One of the missions of the Future Aircraft Carriers Program is to investigate methods that would improve aircraft turnaround servicing activities on carrier decks. The major objectives and criteria for evaluating alternative aircraft servicing methods are to reduce workload requirements, turnaround times (TAT), and life-cycle costs (LCC). Technologies in the field of Robotics and Automation (R and A) have the potential to significantly contribute to these objectives. The objective of this study was to investigate aircraft servicing functions on carrier decks which would offer the potentially most significant payoff if improved by various R and A technologies. Improvement in this case means reducing workload, time and LCC. This objective was accomplished using a ''bottom-up'' formalized approach as described in the following.

Chesser, J.B.; Draper, J.V.; Pin, F.G.

1999-03-01

203

Flight Validation of a Handling Qualities Metric for a Damaged Aircraft  

NASA Technical Reports Server (NTRS)

Objectives: a) Develop an asymmetric handling qualities metric to predict cross coupling effects of a damaged aircraft: 1) Initial use of U.S Army Aeronautical Design Specification ADS-33; 2) Modification as required based on flight test results. b) Simulation and Flight Validation of proposed metric: 1) F-16 VISTA (March 2010); 2) F-18 Full Scale Test bed (Potential Early Experiment); and 3) Flight Simulators (GTM, ACFS, F-18 HILS). c) Provide flight validated metric and tool box to control law designers.

Cogan, Bruce R.

2009-01-01

204

Modeling and parameter uncertainties for aircraft flight control system design  

NASA Technical Reports Server (NTRS)

Values of plant dynamic uncertainties for some recent aircraft design and development programs are given. Histories of pertinent aerodynamic, inertial, and structural parameter variations are given for a period of time from program initiation to aircraft certification. These data can be used as typical of future vehicles so that control system design concepts are evaluated with due consideration to their sensitivity to uncertainties in plant dynamics.

Mcdonnell, J. D.; Berg, R. A.; Heimbaugh, R. M.; Felton, C. A.

1977-01-01

205

Design criteria for integrated flight/propulsion control systems for STOVL fighter aircraft  

NASA Technical Reports Server (NTRS)

As part of NASA's program to develop technology for short takeoff and vertical landing (STOVL) fighter aircraft, control system designs have been developed for a conceptual STOVL aircraft. This aircraft is representative of the class of mixed-flow remote-lift concepts that was identified as the preferred design approach by the US/UK STOVL Joint Assessment and Ranking Team. The control system designs have been evaluated throughout the powered-lift flight envelope on Ames Research Center's Vertical Motion Simulator. Items assessed in the control system evaluation were: maximum control power used in transition and vertical flight, control system dynamic response associated with thrust transfer for attitude control, thrust margin in the presence of ground effect and hot gas ingestion, and dynamic thrust response for the engine core. Effects of wind, turbulence, and ship airwake disturbances are incorporated in the evaluation. Results provide the basis for a reassessment of existing flying qualities design criteria applied to STOVL aircraft.

Franklin, James A.

1993-01-01

206

Towards an Improved Pilot-Vehicle Interface for Highly Automated Aircraft: Evaluation of the Haptic Flight Control System  

NASA Technical Reports Server (NTRS)

The control automation and interaction paradigm (e.g., manual, autopilot, flight management system) used on virtually all large highly automated aircraft has long been an exemplar of breakdowns in human factors and human-centered design. An alternative paradigm is the Haptic Flight Control System (HFCS) that is part of NASA Langley Research Center s Naturalistic Flight Deck Concept. The HFCS uses only stick and throttle for easily and intuitively controlling the actual flight of the aircraft without losing any of the efficiency and operational benefits of the current paradigm. Initial prototypes of the HFCS are being evaluated and this paper describes one such evaluation. In this evaluation we examined claims regarding improved situation awareness, appropriate workload, graceful degradation, and improved pilot acceptance. Twenty-four instrument-rated pilots were instructed to plan and fly four different flights in a fictitious airspace using a moderate fidelity desktop simulation. Three different flight control paradigms were tested: Manual control, Full Automation control, and a simplified version of the HFCS. Dependent variables included both subjective (questionnaire) and objective (SAGAT) measures of situation awareness, workload (NASA-TLX), secondary task performance, time to recognize automation failures, and pilot preference (questionnaire). The results showed a statistically significant advantage for the HFCS in a number of measures. Results that were not statistically significant still favored the HFCS. The results suggest that the HFCS does offer an attractive and viable alternative to the tactical components of today s FMS/autopilot control system. The paper describes further studies that are planned to continue to evaluate the HFCS.

Schutte, Paul; Goodrich, Kenneth; Williams, Ralph

2012-01-01

207

A dynamic backpropagation algorithm with application to gain-scheduled aircraft flight control system design  

Microsoft Academic Search

The authors introduce a dynamic backpropagation algorithm for continuous-time dynamic neural fuzzy systems, as a generalization of the standard backpropagation algorithm for feedforward neural network systems. The proposed algorithm is applied to the design and training of a fuzzy-gain-scheduler for an aircraft flight control system. The trained control system is tested on a full-fledged six-degree-of-freedom nonlinear aircraft simulation package. Simulation

Jianliang Wang; Weiqiang Zhang

1997-01-01

208

Flight service evaluation of Kevlar-49/epoxy composite panels in wide-bodied commercial transport aircraft  

NASA Technical Reports Server (NTRS)

Kevlar-49 fairing panels, installed as flight service components on three L-1011s, were inspected after three years' service, and found to be performing satisfactorily. There are six Kevlar-49 panels on each aircraft, including sandwich and solid laminate wing-body panels, and 150 C service aft engine fairings. The service history to date indicates that Kevlar-49 epoxy composite materials have satisfactory service characteristics for use in aircraft secondary structure.

Stone, R. H.

1977-01-01

209

Expansion of flight simulator capability for study and solution of aircraft directional control problems on runways  

NASA Technical Reports Server (NTRS)

The development, evaluation, and evaluation results of a DC-9-10 runway directional control simulator are described. An existing wide bodied flight simulator was modified to this aircraft configuration. The simulator was structured to use either two of antiskid simulations; (1) an analog mechanization that used aircraft hardware; or (2) a digital software simulation. After the simulation was developed it was evaluated by 14 pilots who made 818 simulated flights. These evaluations involved landings, rejected takeoffs, and various ground maneuvers. Qualitatively most pilots evaluated the simulator as realistic with good potential especially for pilot training for adverse runway conditions.

Kibbee, G. W.

1978-01-01

210

Aircraft Configuration and Flight Crew Compliance with Procedures While Conducting Flight Deck Based Interval Management (FIM) Operations  

NASA Technical Reports Server (NTRS)

Flight deck based Interval Management (FIM) applications using ADS-B are being developed to improve both the safety and capacity of the National Airspace System (NAS). FIM is expected to improve the safety and efficiency of the NAS by giving pilots the technology and procedures to precisely achieve an interval behind the preceding aircraft by a specific point. Concurrently but independently, Optimized Profile Descents (OPD) are being developed to help reduce fuel consumption and noise, however, the range of speeds available when flying an OPD results in a decrease in the delivery precision of aircraft to the runway. This requires the addition of a spacing buffer between aircraft, reducing system throughput. FIM addresses this problem by providing pilots with speed guidance to achieve a precise interval behind another aircraft, even while flying optimized descents. The Interval Management with Spacing to Parallel Dependent Runways (IMSPiDR) human-in-the-loop experiment employed 24 commercial pilots to explore the use of FIM equipment to conduct spacing operations behind two aircraft arriving to parallel runways, while flying an OPD during high-density operations. This paper describes the impact of variations in pilot operations; in particular configuring the aircraft, their compliance with FIM operating procedures, and their response to changes of the FIM speed. An example of the displayed FIM speeds used incorrectly by a pilot is also discussed. Finally, this paper examines the relationship between achieving airline operational goals for individual aircraft and the need for ATC to deliver aircraft to the runway with greater precision. The results show that aircraft can fly an OPD and conduct FIM operations to dependent parallel runways, enabling operational goals to be achieved efficiently while maintaining system throughput.

Shay, Rick; Swieringa, Kurt A.; Baxley, Brian T.

2012-01-01

211

The 1999 Leonid Multi-Instrument Aircraft Campaign - An Early Review  

NASA Astrophysics Data System (ADS)

Two B707-type research aircraft of the 452^nd Flight Test Squadron at Edwards Air Force Base were deployed to study the Leonid meteor storm of 1999 over the Mediterranean Sea on Nov. 18. The mission was sponsored by various science programs of NASA, and offered an international team of 35 researchers observing conditions free of clouds and low altitude extinction at a prime location for viewing the storm. This 1999 Leonid Multi-Instrument Aircraft Campaign followed a similar effort in 1998, improving upon mission strategy and scope. As before, spectroscopic and imaging experiments targeted meteors and persistent trains, but also airglow, aurora, elves and sprites. The research aimed to address outstanding questions in astrobiology, planetary science, astronomy, and upper atmospheric research. In addition, USAF co-sponsored the mission to provide near real-time flux measurements for space weather awareness. First results are presented in these issues of Earth, Moon, and Planets in preparation for future missions that will target the exceptional Leonid returns of 2001 and 2002. An early review of the scientific achievements in the context of campaign objectives is given.

Jenniskens, Peter; Butow, Steven J.; Fonda, Mark

212

Flight experiments using the front-side control technique during piloted approach and landing in a powered lift STOL aircraft  

NASA Technical Reports Server (NTRS)

The essential features of using pitch attitude for glidepath control in conjunction with longitudinal thrust modulation for speed control are described, using a simple linearized model for a powered-lift STOL aircraft operating on the backside of the drag curve and at a fixed setting of propulsive lift. It is shown that an automatic speed-hold system incorporating heave-damping augmentation can allow use of the front-side control technique with satisfactory handling qualities, and the results of previous flight investigations are reviewed. Manual control considerations, as they might be involved following failure of the automatic system, are emphasized. The influence of alternative cockpit controller configurations and flight-director display features were assessed for their effect on the control task, which consisted of a straight-in steep approach flown at constant speed in simulated instrument conditions.

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

1982-01-01

213

A crew-centered flight deck design philosophy for High-Speed Civil Transport (HSCT) aircraft  

NASA Technical Reports Server (NTRS)

Past flight deck design practices used within the U.S. commercial transport aircraft industry have been highly successful in producing safe and efficient aircraft. However, recent advances in automation have changed the way pilots operate aircraft, and these changes make it necessary to reconsider overall flight deck design. The High Speed Civil Transport (HSCT) mission will likely add new information requirements, such as those for sonic boom management and supersonic/subsonic speed management. Consequently, whether one is concerned with the design of the HSCT, or a next generation subsonic aircraft that will include technological leaps in automated systems, basic issues in human usability of complex systems will be magnified. These concerns must be addressed, in part, with an explicit, written design philosophy focusing on human performance and systems operability in the context of the overall flight crew/flight deck system (i.e., a crew-centered philosophy). This document provides such a philosophy, expressed as a set of guiding design principles, and accompanied by information that will help focus attention on flight crew issues earlier and iteratively within the design process. This document is part 1 of a two-part set.

Palmer, Michael T.; Rogers, William H.; Press, Hayes N.; Latorella, Kara A.; Abbott, Terence S.

1995-01-01

214

Lockheed ER-2 #809 high altitude research aircraft in flight  

NASA Technical Reports Server (NTRS)

ER-2 tail number 809, is one of two Airborne Science ER-2s used as science platforms by Dryden. The aircraft are platforms for a variety of high-altitude science missions flown over various parts of the world. They are also used for earth science and atmospheric sensor research and development, satellite calibration and data validation. The ER-2s are capable of carrying a maximum payload of 2,600 pounds of experiments in a nose bay, the main equipment bay behind the cockpit, two wing-mounted superpods and small underbody and trailing edges. Most ER-2 missions last about six hours with ranges of about 2,200 nautical miles. The aircraft typically fly at altitudes above 65,000 feet. On November 19, 1998, the ER-2 set a world record for medium weight aircraft reaching an altitude of 68,700 feet. The aircraft is 63 feet long, with a wingspan of 104 feet. The top of the vertical tail is 16 feet above ground when the aircraft is on the bicycle-type landing gear. Cruising speeds are 410 knots, or 467 miles per hour, at altitude. A single General Electric F118 turbofan engine rated at 17,000 pounds thrust powers the ER-2.

1999-01-01

215

Analog and digital dynamic simulations of a rigid body aircraft in straight and level flight  

E-print Network

. , Texas A&M University Directed by: Dr. Balusu M. Rao A study of the dynamic response characteristics of an aircraft at low approach speeds was conducted using both a digital and an analog computer to simulate a DeHavilland "Beaver" DHC-2 in flight... to produce more sideslip and yawing motions than the rudder with analytical solutions. The problem areas of the STOL aircraft at low approach speeds as a result of a study of the DeHavilland "Beaver" were in lateral stability. The aircraft's response...

Stroman, Morris Michael

1973-01-01

216

Hot-wire anemometry for in-flight measurement of aircraft wake vortices  

NASA Technical Reports Server (NTRS)

A development program has demonstrated that hot-wire anemometry can be used successfully on an aircraft in flight to make measurements of wake vortices produced by another aircraft. The probe, whose wires were made of platinum/rhodium, 10 microns in diameter, provides unambiguous results for inflow angles less than about 35 deg. off the probe axis. The high frequency response capability of the hot-wire system allows detailed measurement of the flow structure, and the study of aircraft hazards associated with wake turbulence.

Jacobsen, R. A.

1977-01-01

217

Adaptive Failure Compensation for Aircraft Flight Control Using Engine Differentials: Regulation  

NASA Technical Reports Server (NTRS)

The problem of using engine thrust differentials to compensate for rudder and aileron failures in aircraft flight control is addressed in this paper in a new framework. A nonlinear aircraft model that incorporates engine di erentials in the dynamic equations is employed and linearized to describe the aircraft s longitudinal and lateral motion. In this model two engine thrusts of an aircraft can be adjusted independently so as to provide the control flexibility for rudder or aileron failure compensation. A direct adaptive compensation scheme for asymptotic regulation is developed to handle uncertain actuator failures in the linearized system. A design condition is specified to characterize the system redundancy needed for failure compensation. The adaptive regulation control scheme is applied to the linearized model of a large transport aircraft in which the longitudinal and lateral motions are coupled as the result of using engine thrust differentials. Simulation results are presented to demonstrate the effectiveness of the adaptive compensation scheme.

Yu, Liu; Xidong, Tang; Gang, Tao; Joshi, Suresh M.

2005-01-01

218

Stratospheric Flight of Three Mars Surface Instrument Prototypes  

NASA Astrophysics Data System (ADS)

The Analog Site Testbed for Readiness Advancement (ASTRA) is a high-altitude balloon platform for the testing of Mars surface instrument systems. In September 2012 three prototype instruments, a mass spectrometer and two anemometers, were taken to the 6 mbar pressure level of Earth's stratosphere (~34.5 km) above New Mexico to demonstrate their current capabilities and identify the critical path-to-flight steps for future advancement. Each of the instrument systems deployed on ASTRA were rated at TRL 4 at the start of the project. Through laboratory development, environmental testing, and the ASTRA balloon flight, each has advanced to an overall system TRL of 5, with specific subsystems reaching TRL 6. The results from the Rapid Acquisition Mass Spectrometer (RAMS), the Hot-Wire Anemometer (HWA), and the Single-Axis Sonic Anemometer (SASA) from the mid-September flight are presented, with focus given to both scientific results of the terrestrial atmospheric investigations, and the engineering and technical performance of the individual instrument systems and the balloon platform. The RAMS instrument has unique ion-imaging optics which permit the acquisition of a complete mass spectrum in a single CCD frame (~50 ms minimum). This allows RAMS to see rapid fluctuations in atmospheric constituents (necessary for the study of, for instance, vapor fluxes to and from the Mars surface) and has potential applications for laser ablation mass spectroscopy. The HWA is the latest generation of hot-wire anemometer, with heritage from the Mars Pathfinder MET instrument, and the ATMIS sensors developed for the Mars Polar Lander and the NetLander project. In addition to wind speed, a thermocouple cage around the hot filament detects heat plume direction, thus permitting 2-D wind vectors to be established. The SASA is a proof-of-capability device for an eventual three-axis sonic anemometer design. Developed under PIDDP funding by Dr. Don Banfield of Cornell (thus a contributed instrument to ASTRA), the SASA uses novel ultrasonic transducers capable of acoustic coupling to the thin Mars atmosphere. Rapid resolution of wind vectors (order 20 Hz), eventual 3-D capability, an open sensing volume, and high sensitivity, accuracy, and precision (order 2 cm/s) make this technique attractive for the measurement of turbulent eddies in the planetary boundary layer.

Hudson, T. L.; Neidholdt, E.; Banfield, D. J.; Kokorowski, M.; Kobie, B.; Diaz, E.; Gordon, S.; Doan, D.; Salami, M.

2012-12-01

219

An intercomparison of aircraft instrumentation for tropospheric measurements of carbonyl sulfide, hydrogen sulfide, and carbon disulfide  

NASA Technical Reports Server (NTRS)

This paper reports results of NASA's Chemical Instrumentation and Test Evaluation (CITE 3) during which airborne measurements for carbonyl sulfide (COS), hydrogen sulfide (H2S), and carbon disulfide (CS2) were intercompared. Instrumentation included a gas chromatograph using flame photometric detection (COS, H2S, and CS2), a gas chromatograph using mass spectrometric detection (COS) and CS2), a gas chromatograph using fluorination and subsequent SF6 detection via electron capture (COS and CS2), and the Natusch technique (H2S). The measurements were made over the Atlantic Ocean east of North and South America during flights from NASA's Wallops Flight Center, Virginia, and Natal, Brazil, in August/September 1989. Most of the intercomparisons for H2S and CS2 were at mixing ratios less than 25 pptv and less than 10 pptv, respectively, with a maximum mixing ratio of about 100 pptv and 50 pptv, respectively. Carbonyl sulfide intercomparisons were at mixing ratios between 400 and 600 pptv. Measurements were intercompared from data bases constructed from time periods of simultaneous or overlapping measurements. Agreement among the COS techniques averaged about 5%, and individual measurements were generally within 10%. For H2S and at mixing ratio greater than 25 pptv, the instruments agreed on average to about 15%. At mixing ratios less than 25 pptv the agreement was about 5 pptv. For CS2 (mixing ratios less than 50 pptv), two techniques agreed on average to about 4 pptv, and the third exhibited a bias (relative to the other two) that varied in the range of 3-7 pptv. CS2 mixing ratios over the ocean east of Natal as measured by the gas chromatograph-mass spectrometer technique were only a few pptv and were below the detection limits of the other two techniques. The CITE 3 data are used to estimate the current uncertainty associated with aircraft measurements of COS, H2S, and CS2 in the remote troposphere.

Gregory, Gerald L.; Davis, Douglas D.; Thornton, Donald C.; Johnson, James E.; Bandy, Alan R.; Saltzman, Eric S.; Andreae, Meinrat O.; Barrick, John D.

1993-01-01

220

Identification of Spey engine dynamics in the augmentor wing jet STOL research aircraft from flight data  

NASA Technical Reports Server (NTRS)

The development and validation of a spey engine model is described. An analysis of the dynamical interactions involved in the propulsion unit is presented. The model was reduced to contain only significant effects, and was used, in conjunction with flight data obtained from an augmentor wing jet STOL research aircraft, to develop initial estimates of parameters in the system. The theoretical background employed in estimating the parameters is outlined. The software package developed for processing the flight data is described. Results are summarized.

Dehoff, R. L.; Reed, W. B.; Trankle, T. L.

1977-01-01

221

The flight test program for the hydrogen powered NASP/X-30 research aircraft  

NASA Technical Reports Server (NTRS)

The NASP/X-30 will be the first U.S. manned aircraft to be powered with hydrogen. Flight testing the X-30 powered with liquid and/or slush hydrogen along with its high speed capability will present unique challenges to the flight test community. The paper describes the overall X-30 flight research program along with some of the key technology challenges. A flight test envelope expansion concept is described along with typical mission profiles. Flight test problems unique to this class of vehicle will be outlined as well as some preliminary thoughts as to solutions to those problems. The X-30 ground operations with hydrogen must be compatible with the normal operations at the flight test site. A concept for the ground support system will be introduced.

Wierzbanowski, Theodore; Armstrong, Johnny G.

1991-01-01

222

Emergency Flight Control of a Twin-Jet Commercial Aircraft using Manual Throttle Manipulation  

NASA Technical Reports Server (NTRS)

The Department of Homeland Security (DHS) created the PCAR (Propulsion-Controlled Aircraft Recovery) project in 2005 to mitigate the ManPADS (man-portable air defense systems) threat to the commercial aircraft fleet with near-term, low-cost proven technology. Such an attack could potentially cause a major FCS (flight control system) malfunction or other critical system failure onboard the aircraft, despite the extreme reliability of current systems. For the situations in which nominal flight controls are lost or degraded, engine thrust may be the only remaining means for emergency flight control [ref 1]. A computer-controlled thrust system, known as propulsion-controlled aircraft (PCA), was developed in the mid 1990s with NASA, McDonnell Douglas and Honeywell. PCA's major accomplishment was a demonstration of an automatic landing capability using only engine thrust [ref 11. Despite these promising results, no production aircraft have been equipped with a PCA system, due primarily to the modifications required for implementation. A minimally invasive option is TOC (throttles-only control), which uses the same control principles as PCA, but requires absolutely no hardware, software or other aircraft modifications. TOC is pure piloting technique, and has historically been utilized several times by flight crews, both military and civilian, in emergency situations stemming from a loss of conventional control. Since the 1990s, engineers at NASA Dryden Flight Research Center (DFRC) have studied TOC, in both simulation and flight, for emergency flight control with test pilots in numerous configurations. In general, it was shown that TOC was effective on certain aircraft for making a survivable landing. DHS sponsored both NASA Dryden Flight Research Center (Edwards, CA) and United Airlines (Denver, Colorado) to conduct a flight and simulation study of the TOC characteristics of a twin-jet commercial transport, and assess the ability of a crew to control an aircraft down to a survivable runway landing using TOC. The PCAR project objective was a set of pilot procedures for operation of a specific aircraft without hydraulics that (a) have been validated in both simulation and flight by relevant personnel, and (b) mesh well with existing commercial operations, maintenance, and training at a minimum cost. As a result of this study, a procedure has been developed to assist a crew in making a survivable landing using TOC. In a simulation environment, line pilots with little or no previous TOC experience performed survivable runway landings after a few practice TOC approaches. In-flight evaluations put line pilots in a simulated emergency situation where TOC was used to recover the aircraft, maneuver to a landing site, and perform an approach down to 200 feet AGL. The results of this research, including pilot observations, procedure comments, recommendations, future work and lessons learned, will he discussed. Flight data and video footage of TOC approaches may also be shown.

Cole, Jennifer H.; Cogan, Bruce R.; Fullerton, C. Gordon; Burken, John J.; Venti, Michael W.; Burcham, Frank W.

2007-01-01

223

Investigating Several Wireless Technologies to Build a Heteregeneous Network for the In-Flight Entertainment System Inside an Aircraft Cabin  

E-print Network

-Flight Entertainment System Inside an Aircraft Cabin Ahmed Akl1,2 , Thierry Gayraud1,2 , Pascal Berthou1,2 1 CNRS when investigating communication requirements in an aircraft cabin is the diverse needs of passengers the aircraft's cabin. Keywords - IFE system; WLAN; WUSB; PLC networks I. INTRODUCTION In recent years, market

Paris-Sud XI, Université de

224

Agile flight control techniques for a fixed-wing aircraft  

E-print Network

As unmanned aerial vehicles (UAVs) become more involved in challenging mission objectives, the need for agility controlled flight becomes more of a necessity. The ability to navigate through constrained environments as ...

Sobolic, Frantisek Michal

2009-01-01

225

Celebrating 100 Years of Flight: Testing Wing Designs in Aircraft  

ERIC Educational Resources Information Center

This article describes an investigation involving several designs of airplane wings in trial flight simulations based on a NASA CONNECT program. Students' experiences with data collection and interpretation are highlighted. (Contains 5 figures.)

Pugalee, David K.; Nusinov, Chuck; Giersch, Chris; Royster, David; Pinelli, Thomas E.

2005-01-01

226

The Insulation of Houses against Noise from Aircraft in Flight.  

ERIC Educational Resources Information Center

Three groups of traditional houses were insulated against aircraft noise by double glazing and installing sound attenuating ventilator units. For upper floor rooms of two story houses, overall insulations of 35-40 dB were obtainable, providing transmission through the roofs and down flues were also reduced. The noise levels caused by ventilator…

Scholes, W. E.; Parkin, P. H.

227

Orion Flight Test-1 Thermal Protection System Instrumentation  

NASA Technical Reports Server (NTRS)

The Orion Crew Exploration Vehicle (CEV) was originally under development to provide crew transport to the International Space Station after the retirement of the Space Shuttle, and to provide a means for the eventual return of astronauts to the Moon. With the current changes in the future direction of the United States human exploration programs, the focus of the Orion project has shifted to the project s first orbital flight test, designated Orion Flight Test 1 (OFT-1). The OFT-1 is currently planned for launch in July 2013 and will demonstrate the Orion vehicle s capability for performing missions in low Earth orbit (LEO), as well as extensibility beyond LEO for select, critical areas. Among the key flight test objectives are those related to validation of the re-entry aerodynamic and aerothermal environments, and the performance of the thermal protection system (TPS) when exposed to these environments. A specific flight test trajectory has been selected to provide a high energy entry beyond that which would be experienced during a typical low Earth orbit return, given the constraints imposed by the possible launch vehicles. This trajectory resulted from a trade study that considered the relative benefit of conflicting objectives from multiple subsystems, and sought to provide the maximum integrated benefit to the re-entry state-of-the-art. In particular, the trajectory was designed to provide: a significant, measureable radiative heat flux to the windward surface; data on boundary transition from laminar to turbulent flow; and data on catalytic heating overshoot on non-ablating TPS. In order to obtain the necessary flight test data during OFT-1, the vehicle will need to have an adequate quantity of instrumentation. A collection of instrumentation is being developed for integration in the OFT-1 TPS. In part, this instrumentation builds upon the work performed for the Mars Science Laboratory Entry, Descent and Landing Instrument (MEDLI) suite to instrument the OFT-1 ablative heat shield. The MEDLI integrated sensor plugs and pressure sensors will be adapted for compatibility with the Orion TPS design. The sensor plugs will provide in-depth temperature data to support aerothermal and TPS model correlation, and the pressure sensors will provide a flush air data system for validation of the entry and descent aerodynamic environments. In addition, a radiometer design will be matured to measure the radiative component of the reentry heating at two locations on the heat shield. For the back shell, surface thermocouple and pressure port designs will be developed and applied which build upon the heritage of the Space Shuttle Program for instrumentation of reusable surface insulation (RSI) tiles. The quantity and location of the sensors has been determined to balance the needs of the reentry disciplines with the demands of the hardware development, manufacturing and integration. Measurements which provided low relative value and presented significant engineering development effort were, unfortunately, eliminated. The final TPS instrumentation has been optimized to target priority test objectives. The data obtained will serve to provide a better understanding of reentry environments for the Orion capsule design, reduce margins, and potentially reduce TPS mass or provide TPS extensibility for alternative missions.

Kowal, T. John

2011-01-01

228

Orbiter/shuttle carrier aircraft separation: Wind tunnel, simulation, and flight test overview and results  

NASA Technical Reports Server (NTRS)

A summary of the approach and landing test phase of the space shuttle program is given from the orbiter/shuttle carrier aircraft separation point of view. The data and analyses used during the wind tunnel testing, simulation, and flight test phases in preparation for the orbiter approach and landing tests are reported.

Homan, D. J.; Denison, D. E.; Elchert, K. C.

1980-01-01

229

A New Wireless Architecture for In-Flight Entertainment Systems Inside Aircraft Cabin  

E-print Network

utilize the wireless technology for the purpose of exchanging data -in both directions- between passengers and the entertainment system. Although wired communication gives better performance than wireless communicationA New Wireless Architecture for In-Flight Entertainment Systems Inside Aircraft Cabin Ahmed AKL

Paris-Sud XI, Université de

230

Airline Transport Pilot, Aircraft Dispatcher, and Flight Navigator. Question Book. Expires September 1, 1991.  

ERIC Educational Resources Information Center

This question book was developed by the Federal Aviation Administration (FAA) for testing applicants who are preparing for certification as airline transport pilots, aircraft dispatchers, or flight navigators. The publication contains several innovative features that are a departure from previous FAA publications related to air carrier personnel…

Federal Aviation Administration (DOT), Washington, DC.

231

Efficiency of the Regulation of Otolith Mineralisation and Susceptibility to kinetotic Behaviour in Parabolic Aircraft Flights  

Microsoft Academic Search

Under diminished gravity e g during the respective phase in the course of parabolic aircraft flight PF humans often suffer from motion sickness a kinetsosis due to sensorimotor disorders Using fish as a model system we previously provided ample evidence that an individually differently pronounced asymmetric mineralisation calcification of inner ear stones otoliths leads to the individually different susceptibility to

M. Knie; J. Weigele; R. Hilbig; R. Anken

2006-01-01

232

Flight of a UV spectrophotometer aboard Galileo 2, the NASA Convair 990 aircraft  

NASA Technical Reports Server (NTRS)

An ultraviolet interference-filter spectrophotometer (UVS) fabricated for aircraft-borne use on the DOT Climatic Impact Assessment Program (CIAP) has been successfully tested in a series of flights on the NASA Convair 990, Galileo II. UV flux data and the calculated total ozone above the flight path are reported for several of the flights. Good agreement is obtained with the total ozone as deducted by integration of an ozone sonde vertical profile obtained at Wallops Island, Virginia near the time of a CV-990 underpass. Possible advantages of use of the UVS in the NASA Global Atmospheric Sampling Program are discussed.

Sellers, B.; Hunderwadel, J. L.; Hanser, F. A.

1976-01-01

233

Non-intrusive testing of an aircraft installed instrument landing system based on DGNSS  

Microsoft Academic Search

This paper describes and analyzes a method of dynamically testing an aircraft installed DGNSS Instrument Approach System, while the aircraft is stationary on the airport ramp, without direct system interconnection. The portable test system produces differential corrections, integrity checks and final approach segment path construction data for each of the pseudoranges transmitted in accordance with the agreed to protocol in

J. F. Michaels

1998-01-01

234

The Genesis Solar Wind Concentrator: Flight and Post-Flight Conditions and Modeling of Instrumental Fractionation  

NASA Astrophysics Data System (ADS)

The Genesis mission Solar Wind Concentrator was built to enhance fluences of solar wind by an average of 20x over the 2.3 years that the mission exposed substrates to the solar wind. The Concentrator targets survived the hard landing upon return to Earth and were used to determine the isotopic composition of solar-wind—and hence solar—oxygen and nitrogen. Here we report on the flight operation of the instrument and on simulations of its performance. Concentration and fractionation patterns obtained from simulations are given for He, Li, N, O, Ne, Mg, Si, S, and Ar in SiC targets, and are compared with measured concentrations and isotope ratios for the noble gases. Carbon is also modeled for a Si target. Predicted differences in instrumental fractionation between elements are discussed. Additionally, as the Concentrator was designed only for ions ?22 AMU, implications of analyzing elements as heavy as argon are discussed. Post-flight simulations of instrumental fractionation as a function of radial position on the targets incorporate solar-wind velocity and angular distributions measured in flight, and predict fractionation patterns for various elements and isotopes of interest. A tighter angular distribution, mostly due to better spacecraft spin stability than assumed in pre-flight modeling, results in a steeper isotopic fractionation gradient between the center and the perimeter of the targets. Using the distribution of solar-wind velocities encountered during flight, which are higher than those used in pre-flight modeling, results in elemental abundance patterns slightly less peaked at the center. Mean fractionations trend with atomic mass, with differences relative to the measured isotopes of neon of +4.1±0.9 ‰/amu for Li, between -0.4 and +2.8 ‰/amu for C, +1.9±0.7‰/amu for N, +1.3±0.4 ‰/amu for O, -7.5±0.4 ‰/amu for Mg, -8.9±0.6 ‰/amu for Si, and -22.0±0.7 ‰/amu for S (uncertainties reflect Monte Carlo statistics). The slopes of the fractionation trends depend to first order only on the relative differential mass ratio, ? m/ m. This article and a companion paper (Reisenfeld et al. 2012, this issue) provide post-flight information necessary for the analysis of the Genesis solar wind samples, and thus serve to complement the Space Science Review volume, The Genesis Mission (v. 105, 2003).

Wiens, Roger C.; Reisenfeld, Daniel B.; Olinger, Chad; Wurz, Peter; Heber, Veronika S.; Burnett, Donald S.

2013-06-01

235

Research Aircraft - Controlling Instruments from the Ground in a Secure and Authenticated Fashion  

NASA Astrophysics Data System (ADS)

At NCAR's Research Aviation Facility (RAF) we're finding a number of factors motivating the desire to be able to control instruments fielded on the aircraft we operate for the NSF. Investigators are increasingly interested in fielding greater numbers of research instruments for projects, instruments are becoming increasingly complicated, and adjustment of instrument behavior to adapt to changing conditions around the aircraft and to meet project goals are just a few of these factors. Usually there are not enough seats on the aircraft to accommodate all the instrument PIs and crew members who do occupy the seats are being asked to monitor and control increasing numbers of instruments about which they have limited knowledge. We use Satellite Communications (SatCom) to allow researchers to communicate with colleagues/crew on the aircraft and so that some of the real-time data can be sent to the ground for helping to optimize the research. Historically, challenges of authentication, security and the disruptive SatCom system have motivated us to avoid providing for remote instrument control. Now we have now reached an era where remote instrument control is a necessity. This poster will discuss the approach we are implementing to provide this capability for our instrument investigators. Particular attention is paid to how we assure authentication and security so that only the instrument investigators are capable of communicating with their instruments.;

Baltzer, T.; Martin, C.; Fawaz, S.; Webster, C.

2012-12-01

236

Jet transport flight operations using cockpit display of traffic information during instrument meteorological conditions: Simulation evaluation  

NASA Technical Reports Server (NTRS)

A simulation study was undertaken to evaluate flight operations using cockpit display of traffic information (CDTI) in a conventional jet transport aircraft. Eight two-person airline flight crews participated as test subjects flying simulated terminal area approach and departure operations under instrument meteorological conditions (IMC). A fixed-base cockpit simulator configured with a full complement of conventional electromechanical instrumentation to permit full workload operations was utilized. Traffic information was displayed on a color cathode-ray tube (CRT) mounted above the throttle quadrant in the typical weather radar location. A transparent touchpanel overlay was utilized for pilot interface with the display. Air traffic control (ATC) simulation included an experienced controller and full partyline radio environment for evaluation of pilot-controlled self-separation and traffic situation monitoring tasks. Results of the study revealed the CDTI to be well received by the test subjects as a useful system which could be incorporated into an existing jet transport cockpit. Crew coordination and consistent operating procedures were identified as important considerations in operational implementation of traffic displays. Cockpit workload was increased with active CDTI tasks. However, all test subjects rated the increase to be acceptable.

Williams, David H.; Wells, Douglas C.

1986-01-01

237

Modern digital flight control system design for VTOL aircraft  

NASA Technical Reports Server (NTRS)

Methods for and results from the design and evaluation of a digital flight control system (DFCS) for a CH-47B helicopter are presented. The DFCS employed proportional-integral control logic to provide rapid, precise response to automatic or manual guidance commands while following conventional or spiral-descent approach paths. It contained altitude- and velocity-command modes, and it adapted to varying flight conditions through gain scheduling. Extensive use was made of linear systems analysis techniques. The DFCS was designed, using linear-optimal estimation and control theory, and the effects of gain scheduling are assessed by examination of closed-loop eigenvalues and time responses.

Broussard, J. R.; Berry, P. W.; Stengel, R. F.

1979-01-01

238

Advanced piloted aircraft flight control system design methodology. Volume 2: The FCX flight control design expert system  

NASA Technical Reports Server (NTRS)

The development of a comprehensive and electric methodology for conceptual and preliminary design of flight control systems is presented and illustrated. The methodology is focused on the design states starting with the layout of system requirements and ending when some viable competing system architectures (feedback control structures) are defined. The approach is centered on the human pilot and the aircraft as both the sources of, and the keys to the solution of, many flight control problems. The methodology relies heavily on computational procedures which are highly interactive with the design engineer. To maximize effectiveness, these techniques, as selected and modified to be used together in the methodology, form a cadre of computational tools specifically tailored for integrated flight control system preliminary design purposes. The FCX expert system as presently developed is only a limited prototype capable of supporting basic lateral-directional FCS design activities related to the design example used. FCX presently supports design of only one FCS architecture (yaw damper plus roll damper) and the rules are largely focused on Class IV (highly maneuverable) aircraft. Despite this limited scope, the major elements which appear necessary for application of knowledge-based software concepts to flight control design were assembled and thus FCX represents a prototype which can be tested, critiqued and evolved in an ongoing process of development.

Myers, Thomas T.; Mcruer, Duane T.

1988-01-01

239

The Goodrich 3rd generation DB-110 system: successful flight test on the F-16 aircraft  

NASA Astrophysics Data System (ADS)

The 3rd Generation Goodrich DB-110 system provides users with a three (3) field-of-view high performance Airborne Reconnaissance capability that incorporates a dual-band day and nighttime imaging sensor, a real time recording and a real time data transmission capability to support long range, medium range, and short range standoff and over-flight mission scenarios, all within a single pod. Goodrich developed their 3rd Generation Airborne Reconnaissance Pod for operation on a range of aircraft types including F-16, F-15, F-18, Euro-fighter and older aircraft such as the F-4, F-111, Mirage and Tornado. This system upgrades the existing, operationally proven, 2nd generation DB-110 design with enhancements in sensor resolution, flight envelope and other performance improvements. Goodrich recently flight tested their 3rd Generation Reconnaissance System on a Block 52 F-16 aircraft with first flight success and excellent results. This paper presents key highlights of the system and presents imaging results from flight test.

Lange, Davis; Iyengar, Mrinal; Maver, Larry; Dyer, Gavin; Francis, John

2007-04-01

240

Induced Moment Effects of Formation Flight Using Two F/A-18 Aircraft  

NASA Technical Reports Server (NTRS)

Previous investigations into formation flight have shown the possibility for significant fuel savings through drag reduction. Using two F/A-18 aircraft, NASA Dryden Flight Research Center has investigated flying aircraft in autonomous formation. Positioning the trailing airplane for best drag reduction requires investigation of the wingtip vortex effects induced by the leading airplane. A full accounting of the vortex effect on the trailing airplane is desired to validate vortex-effect prediction methods and provide a database for the design of a formation flight autopilot. A recent flight phase has mapped the complete wingtip vortex effects at two flight conditions with the trailing airplane at varying distances behind the leading one. Force and moment data at Mach 0.56 and an altitude of 25,000 ft and Mach 0.86 and an altitude of 36,000 ft have been obtained with 20, 55, 110, and 190 ft of longitudinal distance between the aircraft. The moments induced by the vortex on the trailing airplane were well within the pilot's ability to control. This report discusses the data analysis methods and vortex-induced effects on moments and side force. An assessment of the impact of the nonlinear vortex effects on the design of a formation autopilot is offered.

Hansen, Jennifer L.; Cobleigh, Brent R.

2002-01-01

241

Simulator Evaluation of Simplified Propulsion-Only Emergency Flight Control Systems on Transport Aircraft  

NASA Technical Reports Server (NTRS)

With the advent of digital engine control systems, considering the use of engine thrust for emergency flight control has become feasible. Many incidents have occurred in which engine thrust supplemented or replaced normal aircraft flight controls. In most of these cases, a crash has resulted, and more than 1100 lives have been lost. The NASA Dryden Flight Research Center has developed a propulsion-controlled aircraft (PCA) system in which computer-controlled engine thrust provides emergency flight control capability. Using this PCA system, an F-15 and an MD-11 airplane have been landed without using any flight controls. In simulations, C-17, B-757, and B-747 PCA systems have also been evaluated successfully. These tests used full-authority digital electronic control systems on the engines. Developing simpler PCA systems that can operate without full-authority engine control, thus allowing PCA technology to be installed on less capable airplanes or at lower cost, is also a desire. Studies have examined simplified ?PCA Ultralite? concepts in which thrust control is provided using an autothrottle system supplemented by manual differential throttle control. Some of these concepts have worked well. The PCA Ultralite study results are presented for simulation tests of MD-11, B-757, C-17, and B-747 aircraft.

Burcham, Frank W., Jr.; Kaneshige, John; Bull, John; Maine, Trindel A.

1999-01-01

242

A USA Commercial Flight Track Database for Upper Tropospheric Aircraft Emission Studies  

NASA Technical Reports Server (NTRS)

A new air traffic database over the contiguous United States of America (USA) has been developed from a commercially available real-time product for 2001-2003 for all non-military flights above 25,000 ft. Both individual flight tracks and gridded spatially integrated flight legs are available. On average, approximately 24,000 high-altitude flights were recorded each day. The diurnal cycle of air traffic over the USA is characterized by a broad daytime maximum with a 0130-LT minimum and a mean day-night air traffic ratio of 2.4. Each week, the air traffic typically peaks on Thursday and drops to a low Saturday with a range of 18%. Flight density is greatest during late summer and least during winter. The database records the disruption of air traffic after the air traffic shutdown during September 2001. The dataset should be valuable for realistically simulating the atmospheric effects of aircraft in the upper troposphere.

Garber, Donald P.; Minnis, Patrick; Costulis, Kay P.

2003-01-01

243

Advanced AFCS developments on the XV-15 tilt rotor research aircraft. [Automatic Flight Control System  

NASA Technical Reports Server (NTRS)

The design criteria and control and handling qualities of the Automatic Flight Control System (AFCS), developed in the framework of the XV-15 tilt-rotor research aircraft, are evaluated, differentiating between the stability and control criteria. A technically aggressive SCAS control law was implemented, demonstrating that significant benefits accrue when stability criteria are separated from design criteria; the design analyses for application of the control law are presented, and the limit bandwidth for stabilization in hovering flight is shown to be defined by rotor or control lag functions. Flight tests of the aircraft resulted in a rating of 3 on the Cooper-Harper scale; a possibility of achieving a rating of 2 is expected if the system is applied to the yaw and heave control modes.

Churchill, G. B.; Gerdes, R. M.

1984-01-01

244

Multiplexing electro-optic architectures for advanced aircraft integrated flight control systems  

NASA Technical Reports Server (NTRS)

This report describes the results of a 10 month program sponsored by NASA. The objective of this program was to evaluate various optical sensor modulation technologies and to design an optimal Electro-Optic Architecture (EOA) for servicing remote clusters of sensors and actuators in advanced aircraft flight control systems. The EOA's supply optical power to remote sensors and actuators, process the modulated optical signals returned from the sensors, and produce conditioned electrical signals acceptable for use by a digital flight control computer or Vehicle Management System (VMS) computer. This study was part of a multi-year initiative under the Fiber Optic Control System Integration (FOCSI) program to design, develop, and test a totally integrated fiber optic flight/propulsion control system for application to advanced aircraft. Unlike earlier FOCSI studies, this program concentrated on the design of the EOA interface rather than the optical transducer technology itself.

Seal, D. W.

1989-01-01

245

Piloting Vertical Flight Aircraft: A Conference on Flying Qualities and Human Factors  

NASA Technical Reports Server (NTRS)

This document contains papers from a specialists' meeting entitled 'Piloting Vertical Flight Aircraft: A Conference on Flying Qualities and Human Factors.' Vertical flight aircraft, including helicopters and a variety of Vertical Takeoff and Landing (VTOL) concepts, place unique requirements on human perception, control, and performance for the conduct of their design missions. The intent of this conference was to examine, for these vehicles, advances in: (1) design of flight control systems for ADS-33C standards; (2) assessment of human factors influences of cockpit displays and operational procedures; (3) development of VTOL design and operational criteria; and (4) development of theoretical methods or models for predicting pilot/vehicle performance and mission suitability. A secondary goal of the conference was to provide an initial venue for enhanced interaction between human factors and handling qualities specialists.

Blanken, Christopher L. (editor); Whalley, Matthew S. (editor)

1993-01-01

246

Flight control system design for a small unmanned aircraft  

Microsoft Academic Search

The Naval Research Laboratory (NRL) has designed, fabricated and successfully tested a small electrically-powered autonomous unmanned aerial vehicle (UAV). The UAV, which is intended to be a missile decoy, is designed to be deployed with wings and tail surfaces folded from a standard shipboard chaff round launcher. This paper describes the design and development of a microcontroller based automatic flight

C. D. Ozimina; S. K. Tayman; H. E. Chaplin

1995-01-01

247

Parameter estimation techniques and application in aircraft flight testing  

NASA Technical Reports Server (NTRS)

Technical papers presented at the symposium by selected representatives from industry, universities, and various Air Force, Navy, and NASA installations are given. The topics covered include the newest developments in identification techniques, the most recent flight-test experience, and the projected potential for the near future.

1974-01-01

248

The History of the XV-15 Tilt Rotor Research Aircraft from Concept to Flight  

NASA Technical Reports Server (NTRS)

This monograph is a testament to the efforts of many people overcoming multiple technical challenges encountered while developing the XV-15 tilt rotor research aircraft. The Ames involvement with the tilt rotor aircraft began in 1957 with investigations of the performance and dynamic behavior of the Bell XV-3 tilt rotor aircraft. At that time, Ames Research Center was known as the Ames Aeronautical Laboratory of the National Advisory Committee for Aeronautics (NACA). As we approach the new millennium, and after more than 40 years of effort and the successful completion of our initial goals, it is appropriate to reflect on the technical accomplishments and consider the future applications of this unique aircraft class, the tilt rotor. The talented engineers, technicians, managers, and leaders at Ames have worked hard with their counterparts in the U.S. rotorcraft industry to overcome technology barriers and to make the military and civil tilt rotor aircraft safer, environmentally acceptable, and more efficient. The tilt rotor aircraft combines the advantages of vertical takeoff and landing capabilities, inherent to the helicopter, with the forward speed and range of a fixed wing turboprop airplane. Our studies have shown that this new vehicle type can provide the aviation transportation industry with the flexibility for highspeed, long-range flight, coupled with runway-independent operations, thus having a significant potential to relieve airport congestion. We see the tilt rotor aircraft as an element of the solution to this growing air transport problem.

Maisel, Martin D.; Giulianetti, Demo J.; Dugan, Daniel C.

2000-01-01

249

Manual Throttles-Only Control Effectivity for Emergency Flight Control of Transport Aircraft  

NASA Technical Reports Server (NTRS)

If normal aircraft flight controls are lost, emergency flight control may be attempted using only the thrust of engines. Collective thrust is used to control flightpath, and differential thrust is used to control bank angle. One issue is whether a total loss of hydraulics (TLOH) leaves an airplane in a recoverable condition. Recoverability is a function of airspeed, altitude, flight phase, and configuration. If the airplane can be recovered, flight test and simulation results on several transport-class airplanes have shown that throttles-only control (TOC) is usually adequate to maintain up-and-away flight, but executing a safe landing is very difficult. There are favorable aircraft configurations, and also techniques that will improve recoverability and control and increase the chances of a survivable landing. The DHS and NASA have recently conducted a flight and simulator study to determine the effectivity of manual throttles-only control as a way to recover and safely land a range of transport airplanes. This paper discusses TLOH recoverability as a function of conditions, and TOC landability results for a range of transport airplanes, and some key techniques for flying with throttles and making a survivable landing. Airplanes evaluated include the B-747, B-767, B-777, B-757, A320, and B-737 airplanes.

Stevens, Richard; Burcham, Frank W., Jr.

2009-01-01

250

Flight-service program for advanced composite rudders on transport aircraft  

NASA Technical Reports Server (NTRS)

Flight service experience and in-service inspection results are reported for DC-10 graphite composite rudders during the third year of airline service. Test results and status are also reported for ground-based and airborne graphite-epoxy specimens with three different epoxy resin systems to obtain moisture absorption data. Twenty graphite composite rudders were produced, nine of which were installed on commercial aircraft during the past three years. The rudders collectively accumulated 75,863 flight hours. The high time rudder accumulated 12,740 flight hours in slightly over 36 months. The graphite composite rudders were inspected visually at approximately 1000 flight hour intervals and ultrasonically at approximately 3000 flight hour intervals in accordance with in-service inspection plans. All rudders were judged acceptable for continued service as a result of these inspections. Composite moisture absorption data on small specimens, both ground-based and carried aboard three flight-service aircraft, are given. The specimens include Thornel 300 fibers in Narmco 5208 and 5209 resin systems, and Type AS fibers in the Hercules 3501-6 resin system.

1979-01-01

251

Analytical redundancy management mechanization and flight data analysis for the F-8 digital fly-by-wire aircraft flight control sensors  

NASA Technical Reports Server (NTRS)

The details are presented of an onboard digital computer algorithm designed to reliably detect and isolate the first failure in a duplex set of flight control sensors aboard the NASA F-8 digital fly-by-wire aircraft. The algorithm's successful flight test program is summarized, and specific examples are presented of algorithm behavior in response to software-induced signal faults, both with and without aircraft parameter modeling errors.

Deckert, J. C.

1983-01-01

252

Noise of military aircraft in the range of airports and at low level flights  

NASA Astrophysics Data System (ADS)

Military airport noise differs from that of civilian airports in its origins, characteristics, and potential effects. While civilian aircraft frequency spectra are characterized by amplitudes ranging from 75 dB(A) to 85 dB(A), military aircraft amplitudes can range from 70 dB(A) to 120 dB(A). The validity of the equivalent continuous sound level (Leq) as a measure of aircraft noise is evaluated, and the distribution of sound level versus time at various distances is indicated schematically for low-flying aircraft. The distribution reaches 75-80 dB(A) at 5 sec, after which the distribution goes to a plateau at 80-90 dB(A) in a period of 5-10 sec. Low level flights exhibit sound levels greater than 95 dB(A). Through an analysis of these distributions, plotted during landing approach and low-level flights, it is concluded that the Leq is a poor measure of aircraft disturbance.

Hans, V.

253

Flight Test Experience With an Electromechanical Actuator on the F-18 Systems Research Aircraft  

NASA Technical Reports Server (NTRS)

Development of reliable power-by-wire actuation systems for both aeronautical and space applications has been sought recently to eliminate hydraulic systems from aircraft and spacecraft and thus improve safety, efficiency, reliability, and maintainability. The Electrically Powered Actuation Design (EPAD) program was a joint effort between the Air Force, Navy, and NASA to develop and fly a series of actuators validating power-by-wire actuation technology on a primary flight control surface of a tactical aircraft. To achieve this goal, each of the EPAD actuators was installed in place of the standard hydraulic actuator on the left aileron of the NASA F/A-18B Systems Research Aircraft (SRA) and flown throughout the SRA flight envelope. Numerous parameters were recorded, and overall actuator performance was compared with the performance of the standard hydraulic actuator on the opposite wing. This paper discusses the integration and testing of the EPAD electromechanical actuator (EMA) on the SRA. The architecture of the EMA system is discussed, as well as its integration with the F/A-18 Flight Control System. The flight test program is described, and actuator performance is shown to be very close to that of the standard hydraulic actuator it replaced. Lessons learned during this program are presented and discussed, as well as suggestions for future research.

Jensen, Stephen C.; Jenney, Gavin D.; Raymond, Bruce; Dawson, David

2000-01-01

254

Flight Test Experience with an Electromechanical Actuator on the F-18 Systems Research Aircraft  

NASA Technical Reports Server (NTRS)

Development of reliable power-by-wire actuation systems for both aeronautical and space applications has been sought recently to eliminate hydraulic systems from aircraft and spacecraft and thus improve safety, efficiency, reliability, and maintainability. The Electrically Powered Actuation Design (EPAD) program was a joint effort between the Air Force, Navy, and NASA to develop and fly a series of actuators validating power-by-wire actuation technology on a primary flight control surface of a tactical aircraft. To achieve this goal, each of the EPAD actuators was installed in place of the standard hydraulic actuator on the left aileron of the NASA F/A-18B Systems Research Aircraft (SRA) and flown throughout the SRA flight envelope. Numerous parameters were recorded, and overall actuator performance was compared with the performance of the standard hydraulic actuator on the opposite wing. This paper discusses the integration and testing of the EPAD electromechanical actuator (EMA) on the SRA. The architecture of the EMA system is discussed, as well as its integration with the F/A-18 Flight Control System. The flight test program is described, and actuator performance is shown to be very close to that of the standard hydraulic actuator it replaced. Lessons learned during this program are presented and discussed, as well as suggestions for future research.

Jensen, Stephen C.; Jenney, Gavin D.; Raymond, Bruce; Dawson, David; Flick, Brad (Technical Monitor)

2000-01-01

255

Investigation of Flight Test Methods for measuring the performance of general aviation aircraft  

NASA Technical Reports Server (NTRS)

A theoretical and experimental investigation of methods for measuring the performance of general aviation airplanes was conducted using relatively simple instrumentation currently available and data extraction techniques established from efforts in other disciplines. The possibilities of improving flight test data by use of improved modern instrumentation and digital data recording and data analysis were considered.

Bull, G.; Bridges, P.

1981-01-01

256

Monitoring Disasters by Use of Instrumented Robotic Aircraft  

NASA Technical Reports Server (NTRS)

Efforts are under way to develop data-acquisition, data-processing, and data-communication systems for monitoring disasters over large geographic areas by use of uninhabited aerial systems (UAS) robotic aircraft that are typically piloted by remote control. As integral parts of advanced, comprehensive disaster- management programs, these systems would provide (1) real-time data that would be used to coordinate responses to current disasters and (2) recorded data that would be used to model disasters for the purpose of mitigating the effects of future disasters and planning responses to them. The basic idea is to equip UAS with sensors (e.g., conventional video cameras and/or multispectral imaging instruments) and to fly them over disaster areas, where they could transmit data by radio to command centers. Transmission could occur along direct line-of-sight paths and/or along over-the-horizon paths by relay via spacecraft in orbit around the Earth. The initial focus is on demonstrating systems for monitoring wildfires; other disasters to which these developments are expected to be applicable include floods, hurricanes, tornadoes, earthquakes, volcanic eruptions, leaks of toxic chemicals, and military attacks. The figure depicts a typical system for monitoring a wildfire. In this case, instruments aboard a UAS would generate calibrated thermal-infrared digital image data of terrain affected by a wildfire. The data would be sent by radio via satellite to a data-archive server and image-processing computers. In the image-processing computers, the data would be rapidly geo-rectified for processing by one or more of a large variety of geographic-information- system (GIS) and/or image-analysis software packages. After processing by this software, the data would be both stored in the archive and distributed through standard Internet connections to a disaster-mitigation center, an investigator, and/or command center at the scene of the fire. Ground assets (in this case, firefighters and/or firefighting equipment) would also be monitored in real time by use of Global Positioning System (GPS) units and radio communication links between the assets and the UAS. In this scenario, the UAS would serve as a data-relay station in the sky, sending packets of information concerning the locations of assets to the image-processing computer, wherein this information would be incorporated into the geo-rectified images and maps. Hence, the images and maps would enable command-center personnel to monitor locations of assets in real time and in relation to locations affected by the disaster. Optionally, in case of a disaster that disrupted communications, the UAS could be used as an airborne communication relay station to partly restore communications to the affected area. A prototype of a system of this type was demonstrated in a project denoted the First Response Experiment (Project FiRE). In this project, a controlled outdoor fire was observed by use of a thermal multispectral scanning imager on a UAS that delivered image data to a ground station via a satellite uplink/ downlink telemetry system. At the ground station, the image data were geo-rectified in nearly real time for distribution via the Internet to firefighting managers. Project FiRE was deemed a success in demonstrating several advances essential to the eventual success of the continuing development effort.

Wegener, Steven S.; Sullivan, Donald V.; Dunagan, Steven E.; Brass, James A.; Ambrosia, Vincent G.; Buechel, Sally W.; Stoneburner, Jay; Schoenung, Susan M.

2009-01-01

257

Flight test results for the Daedalus and Light Eagle human powered aircraft  

NASA Technical Reports Server (NTRS)

The results of the flight test program of the Daedalus and Light Eagle human powered aircraft in the winter of 1987/88 are given. The results from experiments exploring the Light Eagle's rigid body and structural dynamics are presented. The interactions of these dynamics with the autopilot design are investigated. Estimates of the power required to fly the Daedalus aircraft are detailed. The system of sensors, signal conditioning boards, and data acquisition equipment used to record the flight data is also described. In order to investigate the dynamics of the aircraft, flight test maneuvers were developed to yield maximum data quality from the point of view of estimating lateral and longitudinal stability derivatives. From this data, structural flexibility and unsteady aerodynamics have been modeled in an ad hoc manner and are used to augment the equations of motion with flexibility effects. Results of maneuvers that were flown are compared with the predictions from the flexibility model. To extend the ad hoc flexibility model, a fully flexible aeroelastic model has been developed. The model is unusual in the approximate equality of many structural natural frequencies and the importance of unsteady aerodynamic effects. the Gossamer Albatross. It is hypothesized that this inverse ground effect is caused by turbulence in the Earth's boundary layer. The diameters of the largest boundary layer eddies (which represent most of the turbulent kinetic energy) are proportional to altitude; thus, closer to the ground, the energy in the boundary layer becomes concentrated in eddies of smaller and smaller diameter. Eventually the eddies become sufficiently small (approximately 0.5 cm) that they trip the laminar boundary layer on the wing. As a result, a greater percentage of the wing area is covered with turbulent flow. Consequently the aircraft's drag and the pow er required both increase as the aircraft flies closer to the ground. The results of the flight test program are examined critically, especially with respect to future applications. Maneuvers that allow the observation of stability derivatives for flexible aircraft are detailed. Considerations for the design of autopilots for future human power aircraft and high-altitude RPV's are discussed. Techniques useful in estimating the power required to fly aircraft of very high lift to drag ratio are described.

Sullivan, R. Bryan; Zerweckh, Siegfried H.

1988-01-01

258

What ASRS incident data tell about flight crew performance during aircraft malfunctions  

NASA Technical Reports Server (NTRS)

This research examined 230 reports in NASA's Aviation Safety Reporting System's (ASRS) database to develop a better understanding of factors that can affect flight crew performance when crew are faced with inflight aircraft malfunctions. Each report was placed into one of two categories, based on severity of the malfunction. Report analysis was then conducted to extract information regarding crew procedural issues, crew communications and situational awareness. A comparison of these crew factors across malfunction type was then performed. This comparison revealed a significant difference in ways that crews dealt with serious malfunctions compared to less serious malfunctions. The authors offer recommendations toward improving crew performance when faced with inflight aircraft malfunctions.

Sumwalt, Robert L.; Watson, Alan W.

1995-01-01

259

Pathfinder aircraft prepared for flight showing solar cell arrays on wing  

NASA Technical Reports Server (NTRS)

The solar cell arrays, which cover about 75 percent of its upper wing surface, are clearly evident in this view of the Pathfinder solar-electric aircraft. The solar arrays are capable not only of absorbing direct sunlight, but can also absorb light reflected from the ground through the transparent lower surface of the 98-foot-long wing. Engineers and technicians from Pathfinder's developer, AeroVironment, Inc., conducted a successful two-hour check-out flight from NASA's Dryden Flight Research Center, Edwards, California, on Nov. 19, 1996. The craft then underwent preperations at AeroVironment's Simi Valley, California, facility for a new series of flight tests in Hawaii, during summer, 1997. Pathfinder was a lightweight, solar-powered, remotely piloted flying wing aircraft used to demonstrate the use of solar power for long-duration, high-altitude flight. Its name denotes its mission as the 'Pathfinder' or first in a series of solar-powered aircraft that will be able to remain airborne for weeks or months on scientific sampling and imaging missions. Solar arrays covered most of the upper wing surface of the Pathfinder aircraft. These arrays provided up to 8,000 watts of power at high noon on a clear summer day. That power fed the aircraft's six electric motors as well as its avionics, communications, and other electrical systems. Pathfinder also had a backup battery system that could provide power for two to five hours, allowing for limited-duration flight after dark. Pathfinder flew at airspeeds of only 15 to 20 mph. Pitch control was maintained by using tiny elevators on the trailing edge of the wing while turns and yaw control were accomplished by slowing down or speeding up the motors on the outboard sections of the wing. On September 11, 1995, Pathfinder set a new altitude record for solar-powered aircraft of 50,567 feet above Edwards Air Force Base, California, on a 12-hour flight. On July 7, 1997, it set another, unofficial record of 71,500 feet at the Pacific Missile Range Facility, Kauai, Hawaii. In 1998, Pathfinder was modified into the longer-winged Pathfinder Plus configuration. (See the Pathfinder Plus photos and project description.)

1996-01-01

260

Dryden F-8 Research Aircraft Fleet 1973 in flight, DFBW and SCW  

NASA Technical Reports Server (NTRS)

F-8 Digital Fly-By-Wire (left) and F-8 Supercritical Wing in flight. These two aircraft fundamentally changed the nature of aircraft design. The F-8 DFBW pioneered digital flight controls and led to such computer-controlled airacrft as the F-117A, X-29, and X-31. Airliners such as the Boeing 777 and Airbus A320 also use digital fly-by-wire systems. The other aircraft is a highly modified F-8A fitted with a supercritical wing. Dr. Richard T. Whitcomb of Langley Research Center originated the supercritical wing concept in the late 1960s. (Dr. Whitcomb also developed the concept of the 'area rule' in the early 1950s. It singificantly reduced transonic drag.) The F-8 Digital Fly-By-Wire (DFBW) flight research project validated the principal concepts of all-electric flight control systems now used on nearly all modern high-performance aircraft and on military and civilian transports. The first flight of the 13-year project was on May 25, 1972, with research pilot Gary E. Krier at the controls of a modified F-8C Crusader that served as the testbed for the fly-by-wire technologies. The project was a joint effort between the NASA Flight Research Center, Edwards, California, (now the Dryden Flight Research Center) and Langley Research Center. It included a total of 211 flights. The last flight was December 16, 1985, with Dryden research pilot Ed Schneider at the controls. The F-8 DFBW system was the forerunner of current fly-by-wire systems used in the space shuttles and on today's military and civil aircraft to make them safer, more maneuverable, and more efficient. Electronic fly-by-wire systems replaced older hydraulic control systems, freeing designers to design aircraft with reduced in-flight stability. Fly-by-wire systems are safer because of their redundancies. They are more maneuverable because computers can command more frequent adjustments than a human pilot can. For airliners, computerized control ensures a smoother ride than a human pilot alone can provide. Digital-fly-by-wire is more efficient because it is lighter and takes up less space than the hydraulic systems it replaced. This either reduces the fuel required to fly or increases the number of passengers or pounds of cargo the aircraft can carry. Digital fly-by-wire is currently used in a variety of aircraft ranging from F/A-18 fighters to the Boeing 777. The DFBW research program is considered one of the most significant and most successful NASA aeronautical programs since the inception of the agency. F-8 aircraft were built originally for the U.S. Navy by LTV Aerospace of Dallas, Texas. The aircraft had a wingspan of 35 feet, 2 inches; was 54 feet, 6 inches long; and was powered by a Pratt & Whitney J57 turbojet engine. The F-8 Supercritical Wing was a flight research project designed to test a new wing concept designed by Dr. Richard Whitcomb, chief of the Transonic Aerodynamics Branch, Langley Research Center, Hampton, Virginia. Compared to a conventional wing, the supercritical wing (SCW) is flatter on the top and rounder on the bottom with a downward curve at the trailing edge. The Supercritical Wing was designed to delay the formation of and reduce the shock wave over the wing just below and above the speed of sound (transonic region of flight). Delaying the shock wave at these speeds results in less drag. Results of the NASA flight research at the Flight Research Center, Edwards, California, (later renamed the Dryden Flight Research Center) demonstrated that aircraft using the supercritical wing concept would have increased cruising speed, improved fuel efficiency, and greater flight range than those using conventional wings. As a result, supercritical wings are now commonplace on virtually every modern subsonic commercial transport. Results of the NASA project showed the SCW had increased the transonic efficiency of the F-8 as much as 15 percent and proved that passenger transports with supercritical wings, versus conventional wings, could save $78 million (in 1974 dollars) per year for a fleet of 280 200-passenger airliners. The F-8 Supercritical Wing

1973-01-01

261

Determination of longitudinal aerodynamic derivatives using flight data from an icing research aircraft  

NASA Technical Reports Server (NTRS)

A flight test was performed with the NASA Lewis Research Center's DH-6 icing research aircraft. The purpose was to employ a flight test procedure and data analysis method, to determine the accuracy with which the effects of ice on aircraft stability and control could be measured. For simplicity, flight testing was restricted to the short period longitudinal mode. Two flights were flown in a clean (baseline) configuration, and two flights were flown with simulated horizontal tail ice. Forty-five repeat doublet maneuvers were performed in each of four test configurations, at a given trim speed, to determine the ensemble variation of the estimated stability and control derivatives. Additional maneuvers were also performed in each configuration, to determine the variation in the longitudinal derivative estimates over a wide range of trim speeds. Stability and control derivatives were estimated by a Modified Stepwise Regression (MSR) technique. A measure of the confidence in the derivative estimates was obtained by comparing the standard error for the ensemble of repeat maneuvers, to the average of the estimated standard errors predicted by the MSR program. A multiplicative relationship was determined between the ensemble standard error, and the averaged program standard errors. In addition, a 95 percent confidence interval analysis was performed for the elevator effectiveness estimates, C sub m sub delta e. This analysis identified the speed range where changes in C sub m sub delta e could be attributed to icing effects. The magnitude of icing effects on the derivative estimates were strongly dependent on flight speed and aircraft wing flap configuration. With wing flaps up, the estimated derivatives were degraded most at lower speeds corresponding to that configuration. With wing flaps extended to 10 degrees, the estimated derivatives were degraded most at the higher corresponding speeds. The effects of icing on the changes in longitudinal stability and control derivat

Ranaudo, R. J.; Reehorst, A. L.; Bond, T. H.; Batterson, J. G.; O'Mara, T. M.

1989-01-01

262

Simulation and Flight Evaluation of a Parameter Estimation Input Design Method for Hybrid-Wing-Body Aircraft  

NASA Technical Reports Server (NTRS)

As part of an effort to improve emissions, noise, and performance of next generation aircraft, it is expected that future aircraft will make use of distributed, multi-objective control effectors in a closed-loop flight control system. Correlation challenges associated with parameter estimation will arise with this expected aircraft configuration. Research presented in this paper focuses on addressing the correlation problem with an appropriate input design technique and validating this technique through simulation and flight test of the X-48B aircraft. The X-48B aircraft is an 8.5 percent-scale hybrid wing body aircraft demonstrator designed by The Boeing Company (Chicago, Illinois, USA), built by Cranfield Aerospace Limited (Cranfield, Bedford, United Kingdom) and flight tested at the National Aeronautics and Space Administration Dryden Flight Research Center (Edwards, California, USA). Based on data from flight test maneuvers performed at Dryden Flight Research Center, aerodynamic parameter estimation was performed using linear regression and output error techniques. An input design technique that uses temporal separation for de-correlation of control surfaces is proposed, and simulation and flight test results are compared with the aerodynamic database. This paper will present a method to determine individual control surface aerodynamic derivatives.

Taylor, Brian R.; Ratnayake, Nalin A.

2010-01-01

263

Hybrid Kalman Filter: A New Approach for Aircraft Engine In-Flight Diagnostics  

NASA Technical Reports Server (NTRS)

In this paper, a uniquely structured Kalman filter is developed for its application to in-flight diagnostics of aircraft gas turbine engines. The Kalman filter is a hybrid of a nonlinear on-board engine model (OBEM) and piecewise linear models. The utilization of the nonlinear OBEM allows the reference health baseline of the in-flight diagnostic system to be updated to the degraded health condition of the engines through a relatively simple process. Through this health baseline update, the effectiveness of the in-flight diagnostic algorithm can be maintained as the health of the engine degrades over time. Another significant aspect of the hybrid Kalman filter methodology is its capability to take advantage of conventional linear and nonlinear Kalman filter approaches. Based on the hybrid Kalman filter, an in-flight fault detection system is developed, and its diagnostic capability is evaluated in a simulation environment. Through the evaluation, the suitability of the hybrid Kalman filter technique for aircraft engine in-flight diagnostics is demonstrated.

Kobayashi, Takahisa; Simon, Donald L.

2006-01-01

264

Estimation of Handling Qualities Parameters of the Tu-144 Supersonic Transport Aircraft from Flight Test Data  

NASA Technical Reports Server (NTRS)

Low order equivalent system (LOES) models for the Tu-144 supersonic transport aircraft were identified from flight test data. The mathematical models were given in terms of transfer functions with a time delay by the military standard MIL-STD-1797A, "Flying Qualities of Piloted Aircraft," and the handling qualities were predicted from the estimated transfer function coefficients. The coefficients and the time delay in the transfer functions were estimated using a nonlinear equation error formulation in the frequency domain. Flight test data from pitch, roll, and yaw frequency sweeps at various flight conditions were used for parameter estimation. Flight test results are presented in terms of the estimated parameter values, their standard errors, and output fits in the time domain. Data from doublet maneuvers at the same flight conditions were used to assess the predictive capabilities of the identified models. The identified transfer function models fit the measured data well and demonstrated good prediction capabilities. The Tu-144 was predicted to be between level 2 and 3 for all longitudinal maneuvers and level I for all lateral maneuvers. High estimates of the equivalent time delay in the transfer function model caused the poor longitudinal rating.

Curry, Timothy J.; Batterson, James G. (Technical Monitor)

2000-01-01

265

Sound Pressures and Correlations of Noise on the Fuselage of a Jet Aircraft in Flight  

NASA Technical Reports Server (NTRS)

Tests were conducted at altitudes of 10,000, 20,000, and 30,000 feet at speeds of Mach 0.4, 0.6, and O.8. It was found that the sound pressure levels on the aft fuselage of a jet aircraft in flight can be estimated using an equation involving the true airspeed and the free air density. The cross-correlation coefficient over a spacing of 2.5 feet was generalized with Strouhal number. The spectrum of the noise in flight is comparatively flat up to 10,000 cycles per second.

Shattuck, Russell D.

1961-01-01

266

A flight simulator for advanced aircraft - Servo design to realization.  

NASA Technical Reports Server (NTRS)

Discussion of computer-aided design results obtained for a moving-base, three-man flight simulator. From a control viewpoint, the structure is discussed in terms of disturbance torques, damping ratios, natural frequencies, load acceleration, and smoothness. The use of inertia to achieve well-behaved structural transfer functions and smooth or high fidelity load accelerations is demonstrated. Transfer functions in the complex frequency domain, as well as time-dependent solutions to the system, are derived. The relative merits of using position and/or velocity as primary feedback, for a limited travel acceleration device, are discussed. Root locus plots, which were utilized in the control-system design, Bode plots, and time-dependent plots are drawn. In addition, the theoretical ratio of velocity to commanded input Bode plot is compared to the experimental results, and the dramatic effect on the load smoothness plot caused by selecting velocity over position as primary feedback is shown.

King, R. F.

1973-01-01

267

The 1999 Leonid Multi-Instrument Aircraft Campaign - An Early Review  

Microsoft Academic Search

Two B707-type research aircraft of the 452nd Flight Test Squadron at Edwards Air Force Base were deployed to study the Leonid meteor storm of 1999 over the Mediterranean Sea on Nov. 18. The mission was sponsored by various science programs of NASA, and offered an international team of 35 researchers observing conditions free of clouds and low altitude extinction at

Peter Jenniskens; Steven J. Butow; Mark Fonda

1998-01-01

268

The 1999 Leonid Multi-Instrument Aircraft Campaign - An Early Review  

Microsoft Academic Search

Two B707-type research aircraft of the 452^nd Flight Test Squadron at Edwards Air Force Base were deployed to study the Leonid meteor storm of 1999 over the Mediterranean Sea on Nov. 18. The mission was sponsored by various science programs of NASA, and offered an international team of 35 researchers observing conditions free of clouds and low altitude extinction at

Peter Jenniskens; Steven J. Butow; Mark Fonda

2000-01-01

269

The NASA Dryden Flight Research Center Unmanned Aircraft System Service Capabilities  

NASA Technical Reports Server (NTRS)

Over 60 years of Unmanned Aircraft System (UAS) expertise at the NASA Dryden Flight Research Center are being leveraged to provide capability and expertise to the international UAS community. The DFRC brings together technical experts, UAS, and an operational environment to provide government and industry a broad capability to conduct research, perform operations, and mature systems, sensors, and regulation. The cornerstone of this effort is the acquisition of both a Global Hawk (Northrop Grumman Corporation, Los Angeles, California) and Predator B (General Atomics Aeronautical Systems, Inc., San Diego, California) unmanned aircraft system (UAS). In addition, a test range for small UAS will allow developers to conduct research and development flights without the need to obtain approval from civil authorities. Finally, experts are available to government and industry to provide safety assessments in support of operations in civil airspace. These services will allow developers to utilize limited resources to their maximum capability in a highly competitive environment.

Bauer, Jeff

2007-01-01

270

The NASA Dryden Flight Research Center Unmanned Aircraft System Service Capabilities  

NASA Technical Reports Server (NTRS)

Over 60 years of Unmanned Aircraft System (UAS) expertise at the National Aeronautics and Space Administration (NASA) Dryden Flight Research Center are being leveraged to provide capability and expertise to the international UAS community. The DFRC brings together technical experts, UAS, and an operational environment to provide government and industry a broad capability to conduct research, perform operations, and mature systems, sensors, and regulation. The cornerstone of this effort is the acquisition of both a Global Hawk (Northrop Grumman Corporation, Los Angeles, California) and Predator B (General Atomics Aeronautical Systems, Inc., San Diego, California) unmanned aircraft system (UAS). In addition, a test range for small UAS will allow developers to conduct research and development flights without the need to obtain approval from civil authorities. Finally, experts are available to government and industry to provide safety assessments in support of operations in civil airspace. These services will allow developers to utilize limited resources to their maximum capability in a highly competitive environment.

Bauer, Jeff

2007-01-01

271

In-Flight Lightning Measurements and Reconstruction on a Metallic and Composite Aircraft  

NASA Astrophysics Data System (ADS)

Based on the success of the In-flight Lightning Strike Damage Assessment System (ILDAS) project launched within the scope of the Sixth Framework Programme of the European Commission and completed in July 2009, the results described in this paper form part of the ILDAS2 project initiated by Airbus Operations SAS in partnership with EADS IW and NLR. The principle aim of ILDAS2 project is to develop a system installed aboard an aircraft in order to determine the level, the current waveform and the attachments points of a lightning strike during an aircraft flight. The expectations linked to ILDAS2, the functional architecture of the system, the status and the projection of this development will be presented.

Boiddin, J.-F.; Flourens, F.; De Boer, A.; Bardet, M.; Herve, A.; Perez, G.; Riccio, L.

2012-05-01

272

Flight test evaluation of predicted light aircraft drag, performance, and stability  

NASA Technical Reports Server (NTRS)

A technique was developed which permits simultaneous extraction of complete lift, drag, and thrust power curves from time histories of a single aircraft maneuver such as a pull up (from V max to V stall) and pushover (to V max for level flight). The technique, which is an extension of nonlinear equations of motion of the parameter identification methods of Iliff and Taylor and includes provisions for internal data compatibility improvement as well, was shown to be capable of correcting random errors in the most sensitive data channel and yielding highly accurate results. Flow charts, listings, sample inputs and outputs for the relevant routines are provided as appendices. This technique was applied to flight data taken on the ATLIT aircraft. Lack of adequate knowledge of the correct full throttle thrust horsepower true airspeed variation and considerable internal data inconsistency made it impossible to apply the trajectory matching features of the technique.

Smetana, F. O.; Fox, S. R.

1979-01-01

273

In-flight alignment using H ? filter for strapdown INS on aircraft.  

PubMed

In-flight alignment is an effective way to improve the accuracy and speed of initial alignment for strapdown inertial navigation system (INS). During the aircraft flight, strapdown INS alignment was disturbed by lineal and angular movements of the aircraft. To deal with the disturbances in dynamic initial alignment, a novel alignment method for SINS is investigated in this paper. In this method, an initial alignment error model of SINS in the inertial frame is established. The observability of the system is discussed by piece-wise constant system (PWCS) theory and observable degree is computed by the singular value decomposition (SVD) theory. It is demonstrated that the system is completely observable, and all the system state parameters can be estimated by optimal filter. Then a H ? filter was designed to resolve the uncertainty of measurement noise. The simulation results demonstrate that the proposed algorithm can reach a better accuracy under the dynamic disturbance condition. PMID:24511300

Pei, Fu-Jun; Liu, Xuan; Zhu, Li

2014-01-01

274

48 CFR 1852.228-70 - Aircraft ground and flight risk.  

Code of Federal Regulations, 2011 CFR

...Federal Acquisition Regulations System 6 2011-10-01 2011-10-01...Federal Acquisition Regulations System NATIONAL AERONAUTICS AND...aircraft has completed its landing run upon return and is beached...suits and the execution of instruments of assignment or...

2011-10-01

275

48 CFR 1852.228-70 - Aircraft ground and flight risk.  

Code of Federal Regulations, 2012 CFR

...Federal Acquisition Regulations System 6 2012-10-01 2012-10-01...Federal Acquisition Regulations System NATIONAL AERONAUTICS AND...aircraft has completed its landing run upon return and is beached...suits and the execution of instruments of assignment or...

2012-10-01

276

48 CFR 1852.228-70 - Aircraft ground and flight risk.  

Code of Federal Regulations, 2013 CFR

...Federal Acquisition Regulations System 6 2013-10-01 2013-10-01...Federal Acquisition Regulations System NATIONAL AERONAUTICS AND...aircraft has completed its landing run upon return and is beached...suits and the execution of instruments of assignment or...

2013-10-01

277

48 CFR 1852.228-70 - Aircraft ground and flight risk.  

Code of Federal Regulations, 2014 CFR

...Federal Acquisition Regulations System 6 2014-10-01 2014-10-01...Federal Acquisition Regulations System NATIONAL AERONAUTICS AND...aircraft has completed its landing run upon return and is beached...suits and the execution of instruments of assignment or...

2014-10-01

278

Existence of oscillatory solutions along the path of longitudinal flight equilibriums of an unmanned aircraft, when the automatic flight control system fails  

Microsoft Academic Search

The motion around the center of mass of a rigid unmanned aircraft, whose flight control system fails, in an “Aero Data Model In a Research Environment” is described, by a set of nine nonlinear ordinary differential equations. The longitudinal flight with constant forward velocity is described by a subset of three nonlinear differential equations, obtained from the general system. In

St. Balint; A. M. Balint; E. Kaslik

2010-01-01

279

Mechanical ventilation of critically ill newborns on scheduled flights of commercial passenger aircraft.  

PubMed

Transport of critically sick neonates of any gestation on scheduled commercial passenger aircraft is practical, safe, and cost effective. There is no disruption to boarding or egress of passengers and no seats need be removed or rearranged. Civil Aviation and Federal Aviation Authority regulations are obeyed. Power supply modifications and strengthening of the transport incubator are necessary. Other standard neonatal intensive care equipment can be used in battery mode. Replacement of an endotracheal tube in-flight is not difficult. PMID:3985909

Johnson, R A; Blackler, A D; Lill, B R; Evans, G B

1985-03-01

280

Meteorologically induced variability of sonic-boom characteristics of supersonic aircraft in cruising flight  

Microsoft Academic Search

The influence of the meteorological variability on the characteristics of the primary sonic boom emerging from an aircraft in cruising flight is investigated. The sonic-boom propagation is calculated by means of an advanced ray-tracing algorithm which takes meteorological influences into account. Real meteorological situations are considered based on a full 10-year data set in 12- and\\/or 24-h resolution. Three different

Reinhard Blumrich; François Coulouvrat; Dietrich Heimann

2005-01-01

281

14 CFR 91.1095 - Initial and transition training and checking: Flight instructors (aircraft), flight instructors...  

Code of Federal Regulations, 2010 CFR

...transition training and checking: Flight... Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... AIR TRAFFIC AND GENERAL OPERATING...action in the case of unsatisfactory... (i) The fundamental principles of...Training and practice from the...

2010-01-01

282

14 CFR 135.340 - Initial and transition training and checking: Flight instructors (aircraft), flight instructors...  

Code of Federal Regulations, 2010 CFR

...transition training and checking: Flight... Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... AIR CARRIERS AND OPERATORS FOR...action in the case of unsatisfactory... (i) The fundamental principles of...Training and practice from the...

2010-01-01

283

Ground-Recorded Sonic Boom Signatures of F-18 Aircraft in Formation Flight  

NASA Technical Reports Server (NTRS)

Two F-18 aircraft were flown, one above the other, in two formations, in order for the shock systems of the two aircraft to merge and propagate to the ground. The first formation had the canopy of the lower F-18 in the tail shock of the upper F-18 (called tail-canopy). The second formation had the canopy of the lower F- 18 in the inlet shock of the upper F-18 (called inlet-canopy). The flight conditions were Mach 1.22 and an altitude of 23,500 ft . An array of five sonic boom recorders was used on the ground to record the sonic boom signatures. This paper describes the flight test technique and the ground level sonic boom signatures. The tail-canopy formation resulted in two, separated, N-wave signatures. Such signatures probably resulted from aircraft positioning error. The inlet-canopy formation yielded a single modified signature; two recorders measured an approximate flattop signature. Loudness calculations indicated that the single inlet-canopy signatures were quieter than the two, separated tail-canopy signatures. Significant loudness occurs after a sonic boom signature. Such loudness probably comes from the aircraft engines.

Bahm, Catherine M.; Haering, Edward A., Jr.

1996-01-01

284

Ground-recorded sonic boom signatures of F-18 aircraft formation flight  

NASA Technical Reports Server (NTRS)

Two F-18 aircraft were flown, one above the other, in two formations, in order for the shock systems of the two aircraft to merge and propagate to the ground. The first formation had the canopy of the lower F-18 in the inlet shock of the upper F-18 (called inlet-canopy). The flight conditions were Mach 1.22 and an altitude of 23,500 ft. An array of five sonic boom recorders was used on the ground to record the sonic boom signatures. This paper describes the flight test technique and the ground level sonic boom signatures. The tail-canopy formation resulted in two, separated, N-wave signatures. Such signatures probably resulted from aircraft positioning error. The inlet-canopy formation yielded a single modified signature; two recorders measured an approximate flattop signature. Loudness calculations indicated that the single inlet-canopy signatures were quieter than the two, separated tail-canopy signatures. Significant loudness occurs after a sonic boom signature. Such loudness probably comes from the aircraft engines.

Bahm, Catherine M.; Haering, Edward A., Jr.

1995-01-01

285

14 CFR 125.225 - Flight data recorders.  

Code of Federal Regulations, 2013 CFR

...BOARD SUCH AIRCRAFT Instrument and Equipment Requirements...it has completed the landing roll at an airport...the flight recorder system. Any erasure made...the first pilot's instruments associated with the...recorder. The most recent instrument calibration,...

2013-01-01

286

14 CFR 125.225 - Flight data recorders.  

Code of Federal Regulations, 2011 CFR

...BOARD SUCH AIRCRAFT Instrument and Equipment Requirements...it has completed the landing roll at an airport...the flight recorder system. Any erasure made...the first pilot's instruments associated with the...recorder. The most recent instrument calibration,...

2011-01-01

287

14 CFR 125.225 - Flight data recorders.  

Code of Federal Regulations, 2010 CFR

...BOARD SUCH AIRCRAFT Instrument and Equipment Requirements...it has completed the landing roll at an airport...the flight recorder system. Any erasure made...the first pilot's instruments associated with the...recorder. The most recent instrument calibration,...

2010-01-01

288

14 CFR 125.225 - Flight data recorders.  

Code of Federal Regulations, 2014 CFR

...BOARD SUCH AIRCRAFT Instrument and Equipment Requirements...it has completed the landing roll at an airport...the flight recorder system. Any erasure made...the first pilot's instruments associated with the...recorder. The most recent instrument calibration,...

2014-01-01

289

14 CFR 125.225 - Flight data recorders.  

Code of Federal Regulations, 2012 CFR

...BOARD SUCH AIRCRAFT Instrument and Equipment Requirements...it has completed the landing roll at an airport...the flight recorder system. Any erasure made...the first pilot's instruments associated with the...recorder. The most recent instrument calibration,...

2012-01-01

290

Probing Aircraft Flight Test Hazard Mitigation for the Alternative Fuel Effects on Contrails & Cruise Emissions (ACCESS) Research Team  

NASA Technical Reports Server (NTRS)

The Alternative Fuel Effects on Contrails & Cruise Emissions (ACCESS) Project Integration Manager requested in July 2012 that the NASA Engineering and Safety Center (NESC) form a team to independently assess aircraft structural failure hazards associated with the ACCESS experiment and to identify potential flight test hazard mitigations to ensure flight safety. The ACCESS Project Integration Manager subsequently requested that the assessment scope be focused predominantly on structural failure risks to the aircraft empennage raft empennage.

Kelly, Michael J.

2013-01-01

291

Theseus in Flight  

NASA Technical Reports Server (NTRS)

The twin pusher engines of the prototype Theseus research aircraft can be clearly seen in this photo of the aircraft during a 1996 research flight from the Dryden Flight Research Center, Edwards, California. The Theseus aircraft, built and operated by Aurora Flight Sciences Corporation, Manassas, Virginia, was a unique aircraft flown at NASA's Dryden Flight Research Center, Edwards, California, under a cooperative agreement between NASA and Aurora. Dryden hosted the Theseus program, providing hangar space and range safety for flight testing. Aurora Flight Sciences was responsible for the actual flight testing, vehicle flight safety, and operation of the aircraft. The Theseus remotely piloted aircraft flew its maiden flight on May 24, 1996, at Dryden. During its sixth flight on November 12, 1996, Theseus experienced an in-flight structural failure that resulted in the loss of the aircraft. As of the beginning of the year 2000, Aurora had not rebuilt the aircraft. Theseus was built for NASA under an innovative, $4.9 million fixed-price contract by Aurora Flight Sciences Corporation and its partners, West Virginia University, Morgantown, West Virginia, and Fairmont State College, Fairmont, West Virginia. The twin-engine, unpiloted vehicle had a 140-foot wingspan, and was constructed largely of composite materials. Powered by two 80-horsepower, turbocharged piston engines that drove twin 9-foot-diameter propellers, Theseus was designed to fly autonomously at high altitudes, with takeoff and landing under the active control of a ground-based pilot in a ground control station 'cockpit.' With the potential ability to carry 700 pounds of science instruments to altitudes above 60,000 feet for durations of greater than 24 hours, Theseus was intended to support research in areas such as stratospheric ozone depletion and the atmospheric effects of future high-speed civil transport aircraft engines. Instruments carried aboard Theseus also would be able to validate satellite-based global environmental change measurements. Dryden's Project Manager was John Del Frate.

1996-01-01

292

Assessment of future solid rocket motor flight instrumentation\\/data needs  

Microsoft Academic Search

Results of an assessment of a designer's data needs for solid rocket motor instrumentation is described, along with the state-of-the-art and specialized instrumentation used to date. It is determined that solid rocket motor data obtained during static testing does not always agree with flight test data, and more quantitative data is necessary for motor design. The most promising new flight

W. L. Allen

1981-01-01

293

Complexity and Pilot Workload Metrics for the Evaluation of Adaptive Flight Controls on a Full Scale Piloted Aircraft  

NASA Technical Reports Server (NTRS)

Flight research has shown the effectiveness of adaptive flight controls for improving aircraft safety and performance in the presence of uncertainties. The National Aeronautics and Space Administration's (NASA)'s Integrated Resilient Aircraft Control (IRAC) project designed and conducted a series of flight experiments to study the impact of variations in adaptive controller design complexity on performance and handling qualities. A novel complexity metric was devised to compare the degrees of simplicity achieved in three variations of a model reference adaptive controller (MRAC) for NASA's F-18 (McDonnell Douglas, now The Boeing Company, Chicago, Illinois) Full-Scale Advanced Systems Testbed (Gen-2A) aircraft. The complexity measures of these controllers are also compared to that of an earlier MRAC design for NASA's Intelligent Flight Control System (IFCS) project and flown on a highly modified F-15 aircraft (McDonnell Douglas, now The Boeing Company, Chicago, Illinois). Pilot comments during the IRAC research flights pointed to the importance of workload on handling qualities ratings for failure and damage scenarios. Modifications to existing pilot aggressiveness and duty cycle metrics are presented and applied to the IRAC controllers. Finally, while adaptive controllers may alleviate the effects of failures or damage on an aircraft's handling qualities, they also have the potential to introduce annoying changes to the flight dynamics or to the operation of aircraft systems. A nuisance rating scale is presented for the categorization of nuisance side-effects of adaptive controllers.

Hanson, Curt; Schaefer, Jacob; Burken, John J.; Larson, David; Johnson, Marcus

2014-01-01

294

Flight evaluation of configuration management system concepts during transition to the landing approach for a powered-lift STOL aircraft  

NASA Technical Reports Server (NTRS)

Flight experiments were conducted to evaluate two control concepts for configuration management during the transition to landing approach for a powered-lift STOL aircraft. NASA Ames' augmentor wing research aircraft was used in the program. Transitions from nominal level-flight configurations at terminal area pattern speeds were conducted along straight and curved descending flightpaths. Stabilization and command augmentation for attitude and airspeed control were used in conjunction with a three-cue flight director that presented commands for pitch, roll, and throttle controls. A prototype microwave system provided landing guidance. Results of these flight experiments indicate that these configuration management concepts permit the successful performance of transitions and approaches along curved paths by powered-lift STOL aircraft. Flight director guidance was essential to accomplish the task.

Franklin, J. A.; Innis, R. C.

1980-01-01

295

Pulmonary Function Abnormalities in Never Smoking Flight Attendants Exposed to Secondhand Tobacco Smoke in the Aircraft Cabin  

PubMed Central

Objective To determine whether the flight attendants who were exposed to secondhand tobacco smoke (SHS) in the aircraft cabin have abnormal pulmonary function. Methods We administered questionnaires and performed pulmonary function testing in 61 never-smoking female flight attendants who worked in active air crews before the smoking ban on commercial aircraft (pre-ban). Results While the pre-ban flight attendants had normal FVC, FEV1, and FEV1/FVC ratio, they had significantly decreased flow at mid- and low-lung volumes, curvilinear flow-volume curves, and evidence of air trapping. Furthermore, the flight attendants had significantly decreased diffusing capacity (77.5±11.2 %predicted normal) with 51% having a diffusing capacity below their 95% normal prediction limit. Conclusions This cohort of healthy never-smoking flight attendants who were exposed to SHS in the aircraft cabin showed pulmonary function abnormalities suggestive of airway obstruction and impaired diffusion. PMID:19448573

Arjomandi, Mehrdad; Haight, Thaddeus; Redberg, Rita; Gold, Warren M

2009-01-01

296

Genetic algorithms for tuning fuzzy membership functions in flight control software  

E-print Network

to their general aviation brethren. One project developed during the course of this research was a Flight Mode Interpreter (FMI). The FMI performs real-time, high-level situation recognition based on data from aircraft flight instruments. Flight modes...

Harral, Vance Quinton

2012-06-07

297

A Flight Evaluation of an Airborne Physiological Instrumentation System, Including Preliminary Results Under Conditions of Varying Accelerations  

NASA Technical Reports Server (NTRS)

A physiological instrumentation system capable of recording the electrocardiogram, pulse rate, respiration rate, and systolic and diastolic blood pressures during flight has been developed. This instrumentation system was designed for use during control studies at varied levels of acceleration in order to monitor the well-being of the pilot and at the same time to obtain data for study of the relationships between his various physiological functions and his performance capability. Flights, made in a T-33 aircraft, demonstrated the ability of the system to obtain the desired physiological data in flight. The data obtained in these flights, although limited in nature, indicate a slowing of the pulse rate under the subgravity conditions of brief duration. There appeared to be a proportional nearly in-phase relationship between pulse rate and acceleration. A decrease in diastolic blood pressure together with an increase in pulse pressure was noted during subgravity conditions and an elevation of the diastolic pressure together with a decrease in pulse pressure du-ring increased accelerations. No change worthy of note was seen in the records of the systolic blood pressure, the respiration rate, or the electrocardiogram over the range of acceleration studied (0 to 3 g).

Smedal, Harald A.; Holden, George R.; Smith, Joseph R., Jr.

1960-01-01

298

NASA rotor systems research aircraft: Fixed-wing configuration flight-test results  

NASA Technical Reports Server (NTRS)

The fixed-wing, airplane configuration flight-test results of the Rotor System Research Aircraft (RSRA), NASA 740, at Ames/Dryden Flight Research Center are documented. Fourteen taxi and flight tests were performed from December 1983 to October 1984. This was the first time the RSRA was flown with the main rotor removed; the tail rotor was installed. These tests confirmed that the RSRA is operable as a fixed-wing aircraft. Data were obtained for various takeoff and landing distances, control sensitivity, trim and dynamics stability characteristics, performance rotor-hub drag, and acoustics signature. Stability data were obtained with the rotor hub both installed and removed. The speed envelope was developed to 261 knots true airspeed (KTAS), 226 knots calibrated airspeed (KCAS) at 10,000 ft density altitude. The airplane was configured at 5 deg. wing incidence with 5 deg. wing flaps as a normal configuration. Level-flight data were acquired at 167 KCAS for wing incidence from 0 to 10 deg. Step inputs and doublet inputs of various magnitudes were utilized to acquire dynamic stability and control sensitivity data. Sine-wave inputs of constantly increasing frequency were used to generate parameter identification data. The maximum load factor attained was 2.34 g at 206 KCAS.

Erickson, R. E.; Cross, J. L.; Kufeld, R. M.; Acree, C. W.; Nguyen, D.; Hodge, R. W.

1986-01-01

299

Design and piloted simulation evaluation of integrated flight/propulsion controls for STOVL aircraft  

NASA Technical Reports Server (NTRS)

Integrated flight/propulsion control systems have been designed for operation of STOVL aircraft over the low speed powered-lift flight envelope. The control system employs command modes for attitude, flightpath angle and flightpath acceleration during transition, and translational velocity command for hover and vertical landing. The command modes and feedback control are implemented in the form of a state-rate feedback implicit model follower to achieve the desired flying qualities and to suppress the effects of external disturbances and variations in the aircraft characteristics over the low speed envelope. A nonlinear inverse system was used to translate the output from these commands and feedback control into commands for the various aerodynamic and propulsion control effectors that are employed in powered-lift flight. Piloted evaluations of these STOVL integrated control designs have been conducted on Ames Research Center's Vertical Motion Simulator to assess flying qualities over the low-speed flight envelope. Results indicate that Level 1 flying qualities are achieved with this control system concept for each of these low-speed operations over a wide range of wind, atmospheric turbulence, and visibility conditions.

Franklin, James A.; Engelland, Shawn A.

1991-01-01

300

Advanced piloted aircraft flight control system design methodology. Volume 1: Knowledge base  

NASA Technical Reports Server (NTRS)

The development of a comprehensive and electric methodology for conceptual and preliminary design of flight control systems is presented and illustrated. The methodology is focused on the design stages starting with the layout of system requirements and ending when some viable competing system architectures (feedback control structures) are defined. The approach is centered on the human pilot and the aircraft as both the sources of, and the keys to the solution of, many flight control problems. The methodology relies heavily on computational procedures which are highly interactive with the design engineer. To maximize effectiveness, these techniques, as selected and modified to be used together in the methodology, form a cadre of computational tools specifically tailored for integrated flight control system preliminary design purposes. While theory and associated computational means are an important aspect of the design methodology, the lore, knowledge and experience elements, which guide and govern applications are critical features. This material is presented as summary tables, outlines, recipes, empirical data, lists, etc., which encapsulate a great deal of expert knowledge. Much of this is presented in topical knowledge summaries which are attached as Supplements. The composite of the supplements and the main body elements constitutes a first cut at a a Mark 1 Knowledge Base for manned-aircraft flight control.

Mcruer, Duane T.; Myers, Thomas T.

1988-01-01

301

The measurement of aircraft performance and stability and control after flight through natural icing conditions  

NASA Technical Reports Server (NTRS)

The effects of airframe icing on the performance and stability and control of a twin-engine commuter-class aircraft were measured by the NASA Lewis Research Center. This work consisted of clear air tests with artificial ice shapes attached to the horizontal tail, and natural icing flight tests in measured icing clouds. The clear air tests employed static longitudinal flight test methods to determine degradation in stability margins for four simulated ice shapes. The natural icing flight tests employed a data acquisition system, which was provided under contract to NASA by Kohlman Systems Research Incorporated. This system used a performance modeling method and modified maximum likelihood estimation (MMLE) technique to determine aircraft performance degradation and stability and control. Flight test results with artificial ice shapes showed that longitudinal, stick-fixed, static margins are reduced on the order of 5 percent with flaps up. Natural icing tests with the KSR system corroborated these results and showed degradation in the elevator control derivatives on the order of 8 to 16 percent depending on wing flap configuration. Performance analyses showed the individual contributions of major airframe components to the overall degradation in lift and drag.

Ranaudo, R. J.; Mikkelsen, K. L.; Mcknight, R. C.; Ide, R. F.; Reehorst, A. L.

1986-01-01

302

The measurement of aircraft performance and stability and control after flight through natural icing conditions  

NASA Technical Reports Server (NTRS)

The effects of airframe icing on the performance and stability and control of a twin-engine commuter-class aircraft were measured by the NASA Lewis Research Center. This work consisted of clear air tests with artificial ice shapes attached to the horizontal tail, and natural icing flight tests in measured icing clouds. The clear air tests employed static longitudinal flight test methods to determine degradation in stability margins for four simulated ice shapes. The natural icing flight tests employed a data acquisition system, which was provided under contract to NASA by Kohlman Systems Research Incorporated. This system used a performance modeling method and modified maximum likelihood estimation (MMLE) technique to determine aircraft performance degradation and stability and control. Flight test results with artificial ice shapes showed that longitudinal, stick-fixed, static margins are reduced on the order of 5 percent with flaps up. Natural icing tests with the KSR system corroborated these results and showed degradation in the elevator control derivatives on the order of 8 to 16 percent depending on wing flap configuration. Performance analyses showed the individual contributions of major airframe components to the overall degration in lift and drag.

Ranaudo, R. J.; Mikkelsen, K. L.; Mcknight, R. C.; Ide, R. F.; Reehorst, A. L.; Jordan, J. L.; Schinstock, W. C.; Platz, S. J.

1986-01-01

303

High-angle-of-attack yawing moment asymmetry of the X-31 aircraft from flight test  

NASA Technical Reports Server (NTRS)

Significant yawing moment asymmetries were encountered during the high-angle-of-attack envelope expansion of the two X-31 aircraft. These asymmetries led to position saturations of the thrust vector vanes and trailing-edge flaps during some of the dynamic stability axis rolling maneuvers at high angles of attack. This slowed the high-angle-of-attack envelope expansion and resulted in maneuver restrictions. Several aerodynamic modifications were made to the X-31 forebody with the goal of minimizing the asymmetry. A method for determining the yawing moment asymmetry from flight data was developed and an analysis of the various configuration changes completed. The baseline aircraft were found to have significant asymmetries above 45 deg angle of attack with the largest asymmetry typically occurring around 60 deg angle of attack. Applying symmetrical boundary layer transition strips along the forebody sides increased the magnitude of the asymmetry and widened the angle-of-attack range over which the largest asymmetry acted. Installing longitudinal forebody strakes and rounding the sharp nose of the aircraft caused the yawing moment asymmetry magnitude to be reduced. The transition strips and strakes made the asymmetry characteristic of the aircraft more repeatable than the clean forebody configuration. Although no geometric differences between the aircraft were known, ship 2 consistently had larger yawing moment asymmetries than ship 1.

Cobleigh, Brent R.

1994-01-01

304

Follow on Researches for X-56A Aircraft at NASA Dryden Flight Research Center (Progress Report)  

NASA Technical Reports Server (NTRS)

A lot of composite materials are used for the modern aircraft to reduce its weight. Aircraft aeroservoelastic models are typically characterized by significant levels of model parameter uncertainty due to composite manufacturing process. Small modeling errors in the finite element model will eventually induce errors in the structural flexibility and mass, thus propagating into unpredictable errors in the unsteady aerodynamics and the control law design. One of the primary objectives of X-56A aircraft is the flight demonstration of active flutter suppression, and therefore in this study, the identification of the primary and secondary modes is based on the flutter analysis of X-56A aircraft. It should be noted that for all three Mach number cases rigid body modes and mode numbers seven and nine are participated 89.1 92.4 % of the first flutter mode. Modal participation of the rigid body mode and mode numbers seven and nine for the second flutter mode are 94.6 96.4%. Rigid body mode and the first two anti-symmetric modes, eighth and tenth modes, are participated 93.2 94.6% of the third flutter mode. Therefore, rigid body modes and the first four flexible modes of X-56A aircraft are the primary modes during the model tuning procedure. The ground vibration test-validated structural dynamic finite element model of the X-56A aircraft is to obtain in this study. The structural dynamics finite element model of X-56A aircraft is improved using the parallelized big-bang big-crunch algorithm together with a hybrid optimization technique.

Pak, Chan-Gi

2012-01-01

305

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

NASA Technical Reports Server (NTRS)

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.

Neuman, F.; Hardy, G. H.

1981-01-01

306

A review of supersonic cruise flight path control experience with the YF-12 aircraft  

NASA Technical Reports Server (NTRS)

Flight research with the YF-12 aircraft indicates that solutions to many handling qualities problems of supersonic cruise are at hand. Airframe/propulsion system interactions in the Dutch roll mode can be alleviated by the use of passive filters or additional feedback loops in the propulsion and flight control systems. Mach and altitude excursions due to atmospheric temperature fluctuations can be minimized by the use of a cruise autothrottle. Autopilot instabilities in the altitude hold mode have been traced to angle of attack-sensitive static ports on the compensated nose boom. For the YF-12, the feedback of high-passed pitch rate to the autopilot resolves this problem. Manual flight path control is significantly improved by the use of an inertial rate of climb display in the cockpit.

Berry, D. T.; Gilyard, G. B.

1976-01-01

307

ERAST Program Proteus Aircraft in Flight over the Mojave Desert in California  

NASA Technical Reports Server (NTRS)

The unusual design of the Proteus high-altitude aircraft, incorporating a gull-wing shape for its main wing and a long, slender forward canard, is clearly visible in this view of the aircraft in flight over the Mojave Desert in California. In the Proteus Project, NASA's Dryden Flight Research Center, Edwards, California, is assisting Scaled Composites, Inc., Mojave, California, in developing a sophisticated station-keeping autopilot system and a Satellite Communications (SATCOM)-based uplink-downlink data system for aircraft and payload data under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) project. The ERAST Project is sponsored by the Office of Aero-Space Technology at NASA Headquarters, and is managed by the Dryden Flight Research Center. The Proteus is a unique aircraft, designed as a high-altitude, long-duration telecommunications relay platform with potential for use on atmospheric sampling and Earth-monitoring science missions. The aircraft is designed to be flown by two pilots in a pressurized cabin, but also has the potential to perform its missions semiautonomously or be flown remotely from the ground. Flight testing of the Proteus, beginning in the summer of 1998 at Mojave Airport through the end of 1999, included the installation and checkout of the autopilot system, including the refinement of the altitude hold and altitude change software. The SATCOM equipment, including avionics and antenna systems, had been installed and checked out in several flight tests. The systems performed flawlessly during the Proteus's deployment to the Paris Airshow in 1999. NASA's ERAST project funded development of an Airborne Real-Time Imaging System (ARTIS). Developed by HyperSpectral Sciences, Inc., the small ARTIS camera was demonstrated during the summer of 1999 when it took visual and near-infrared photos over the Experimental Aircraft Association's 'AirVenture 99' Airshow at Oshkosh, Wisconsin. The images were displayed on a computer monitor at the show only moments after they were taken. This was the second successful demonstration of the ARTIS camera. The aircraft is designed to cruise at altitudes from 59,000 to more than 65,000 feet for up to 18 hours. It was designed and built by Burt Rutan, president of Scaled Composites, Inc., to carry an 18-foot diameter telecommunications antenna system for relay of broadband data over major cities. The design allows for Proteus to be reconfigured at will for a variety of other missions such as atmospheric research, reconnaissance, commercial imaging, and launch of small space satellites. It is designed for extreme reliability and low operating costs, and to operate out of general aviation airports with minimal support. The aircraft consists of an all composite airframe with graphite-epoxy sandwich construction. It has a wingspan of 77 feet 7 inches, expandable to 92 feet with removable wingtips installed. It is 56.3 feet long and 17.6 feet high and weighs 5,900 pounds, empty. Proteus is powered by two Williams-Rolls FJ44-2 turbofan engines developing 2,300 pounds of thrust each.

1999-01-01

308

Validation of Aqua satellite data in the upper troposphere and lower stratosphere with in situ aircraft instruments  

E-print Network

aircraft instruments A. Gettelman,1 E. M. Weinstock,2 E. J. Fetzer,3 F. W. Irion,3 A. Eldering,3 E. C June 2004; revised 3 September 2004; accepted 26 October 2004; published 24 November 2004. [1] Aircraft in the upper troposphere and lower stratosphere. Satellite observations compare well to aircraft data

Gettelman, Andrew

309

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)

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).

Gerren, Donna S.

1993-01-01

310

ERAST Program Proteus Aircraft in Flight over the Tehachapi Mountains in Southern California  

NASA Technical Reports Server (NTRS)

The unique shape of the Proteus high-altitude aircraft is clearly visible in this photo of the plane in flight above the rocky slopes of the Tehachapi Mountains near Mojave, California, where the Proteus was designed and built. In the Proteus Project, NASA's Dryden Flight Research Center, Edwards, California, is assisting Scaled Composites, Inc., Mojave, California, in developing a sophisticated station-keeping autopilot system and a Satellite Communications (SATCOM)-based uplink-downlink data system for aircraft and payload data under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) project. The ERAST Project is sponsored by the Office of Aero-Space Technology at NASA Headquarters, and is managed by the Dryden Flight Research Center. The Proteus is a unique aircraft, designed as a high-altitude, long-duration telecommunications relay platform with potential for use on atmospheric sampling and Earth-monitoring science missions. The aircraft is designed to be flown by two pilots in a pressurized cabin, but also has the potential to perform its missions semiautonomously or be flown remotely from the ground. Flight testing of the Proteus, beginning in the summer of 1998 at Mojave Airport through the end of 1999, included the installation and checkout of the autopilot system, including the refinement of the altitude hold and altitude change software. The SATCOM equipment, including avionics and antenna systems, had been installed and checked out in several flight tests. The systems performed flawlessly during the Proteus's deployment to the Paris Airshow in 1999. NASA's ERAST project funded development of an Airborne Real-Time Imaging System (ARTIS). Developed by HyperSpectral Sciences, Inc., the small ARTIS camera was demonstrated during the summer of 1999 when it took visual and near-infrared photos over the Experimental Aircraft Association's 'AirVenture 99' Airshow at Oshkosh, Wisconsin. The images were displayed on a computer monitor at the show only moments after they were taken. This was the second successful demonstration of the ARTIS camera. The aircraft is designed to cruise at altitudes from 59,000 to more than 65,000 feet for up to 18 hours. It was designed and built by Burt Rutan, president of Scaled Composites, Inc., to carry an 18-foot diameter telecommunications antenna system for relay of broadband data over major cities. The design allows for Proteus to be reconfigured at will for a variety of other missions such as atmospheric research, reconnaissance, commercial imaging, and launch of small space satellites. It is designed for extreme reliability and low operating costs, and to operate out of general aviation airports with minimal support. The aircraft consists of an all composite airframe with graphite-epoxy sandwich construction. It has a wingspan of 77 feet 7 inches, expandable to 92 feet with removable wingtips installed. It is 56.3 feet long and 17.6 feet high and weighs 5,900 pounds,empty. Proteus is powered by two Williams-Rolls FJ44-2 turbofan engines developing 2,300 pounds of thrust each.

1999-01-01

311

ERAST Program Proteus Aircraft in Flight over the Mojave Desert in California  

NASA Technical Reports Server (NTRS)

The uniquely shaped Proteus high-altitude aircraft soars over California's Mojave Desert during a July 1999 flight. In the Proteus Project, NASA's Dryden Flight Research Center, Edwards, California, is assisting Scaled Composites, Inc., Mojave, California, in developing a sophisticated station-keeping autopilot system and a Satellite Communications (SATCOM)-based uplink-downlink data system for aircraft and payload data under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) project. The ERAST Project is sponsored by the Office of Aero-Space Technology at NASA Headquarters, and is managed by the Dryden Flight Research Center. The Proteus is a unique aircraft, designed as a high-altitude, long-duration telecommunications relay platform with potential for use on atmospheric sampling and Earth-monitoring science missions. The aircraft is designed to be flown by two pilots in a pressurized cabin, but also has the potential to perform its missions semiautonomously or be flown remotely from the ground. Flight testing of the Proteus, beginning in the summer of 1998 at Mojave Airport through the end of 1999, included the installation and checkout of the autopilot system, including the refinement of the altitude hold and altitude change software. The SATCOM equipment, including avionics and antenna systems, had been installed and checked out in several flight tests. The systems performed flawlessly during the Proteus's deployment to the Paris Airshow in 1999. NASA's ERAST project funded development of an Airborne Real-Time Imaging System (ARTIS). Developed by HyperSpectral Sciences, Inc., the small ARTIS camera was demonstrated during the summer of 1999 when it took visual and near-infrared photos over the Experimental Aircraft Association's 'AirVenture 99' Airshow at Oshkosh, Wisconsin. The images were displayed on a computer monitor at the show only moments after they were taken. This was the second successful demonstration of the ARTIS camera. The aircraft is designed to cruise at altitudes from 59,000 to more than 65,000 feet for up to 18 hours. It was designed and built by Burt Rutan, president of Scaled Composites, Inc., to carry an 18-foot diameter telecommunications antenna system for relay of broadband data over major cities. The design allows for Proteus to be reconfigured at will for a variety of other missions such as atmospheric research, reconnaissance, commercial imaging, and launch of small space satellites. It is designed for extreme reliability and low operating costs, and to operate out of general aviation airports with minimal support. The aircraft consists of an all composite airframe with graphite-epoxy sandwich construction. It has a wingspan of 77 feet 7 inches, expandable to 92 feet with removable wingtips installed. It is 56.3 feet long and 17.6 feet high and weighs 5,900 pounds, empty. Proteus is powered by two Williams-Rolls FJ44-2 turbofan engines developing 2,300 pounds of thrust each.

1999-01-01

312

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

NASA Technical Reports Server (NTRS)

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.

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

1995-01-01

313

Aircraft as Research Tools  

NASA Technical Reports Server (NTRS)

Aeronautical research usually begins with computers, wind tunnels, and flight simulators, but eventually the theories must fly. This is when flight research begins, and aircraft are the primary tools of the trade. Flight research involves doing precision maneuvers in either a specially built experimental aircraft or an existing production airplane that has been modified. For example, the AD-1 was a unique airplane made only for flight research, while the NASA F-18 High Alpha Research Vehicle (HARV) was a standard fighter aircraft that was transformed into a one-of-a-kind aircraft as it was fitted with new propulsion systems, flight controls, and scientific equipment. All research aircraft are able to perform scientific experiments because of the onboard instruments that record data about its systems, aerodynamics, and the outside environment. Since the 1970's, NASA flight research has become more comprehensive, with flights involving everything form Space Shuttles to ultralights. NASA now flies not only the fastest airplanes, but some of the slowest. Flying machines continue to evolve with new wing designs, propulsion systems, and flight controls. As always, a look at today's experimental research aircraft is a preview of the future.

1999-01-01

314

A Correlation Between Flight-Determined Derivatives and Wind-Tunnel Data for the X-24B Research Aircraft  

NASA Technical Reports Server (NTRS)

Longitudinal and lateral-directional estimates of the aerodynamic derivatives of the X-24B research aircraft were obtained from flight data by using a modified maximum likelihood estimation method. Data were obtained over a Mach number range from 0.35 to 1.72 and over an angle of attack range from 3.5 deg. to 15.7 deg. Data are presented for a subsonic and transonic configuration. The flight derivatives were generally consistent and documented the aircraft well. The correlation between the flight data and wind-tunnel predictions is presented and discussed.

Sim, Alex G.

1997-01-01

315

A Correlation Between Flight-Determined Derivatives and Wind-Tunnel Data for the X-24B Research Aircraft  

NASA Technical Reports Server (NTRS)

Longitudinal and lateral-directional estimates of the aerodynamic derivatives of the X-24B research aircraft were obtained from flight data by using a modified maximum likelihooa estimation method. Data were obtained over a Mach number range from 0.35 to 1.72 and over an angle of attack range from 3.5deg to 15.7deg. Data are presented for a subsonic and a transonic configuration. The flight derivatives were generally consistent and documented the aircraft well. The correlation between the flight data and wind-tunnel predictions is presented and discussed.

Sim, Alex G.

1976-01-01

316

Flight Test Evaluation of Situation Awareness Benefits of Integrated Synthetic Vision System Technology f or Commercial Aircraft  

NASA Technical Reports Server (NTRS)

Research was conducted onboard a Gulfstream G-V aircraft to evaluate integrated Synthetic Vision System concepts during flight tests over a 6-week period at the Wallops Flight Facility and Reno/Tahoe International Airport. The NASA Synthetic Vision System incorporates database integrity monitoring, runway incursion prevention alerting, surface maps, enhanced vision sensors, and advanced pathway guidance and synthetic terrain presentation. The paper details the goals and objectives of the flight test with a focus on the situation awareness benefits of integrating synthetic vision system enabling technologies for commercial aircraft.

Prinzel, Lawrence J., III; Kramer, Lynda J.; Arthur, Jarvis J., III

2005-01-01

317

14 CFR 29.1331 - Instruments using a power supply.  

Code of Federal Regulations, 2011 CFR

... Instruments using a power supply. 29.1331 Section...DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS... Instruments using a power supply. For category A rotorcraft...flight instrument using a power supply must have—...

2011-01-01

318

14 CFR 29.1331 - Instruments using a power supply.  

Code of Federal Regulations, 2014 CFR

... Instruments using a power supply. 29.1331 Section...DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS... Instruments using a power supply. For category A rotorcraft...flight instrument using a power supply must have—...

2014-01-01

319

14 CFR 29.1331 - Instruments using a power supply.  

Code of Federal Regulations, 2013 CFR

... Instruments using a power supply. 29.1331 Section...DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS... Instruments using a power supply. For category A rotorcraft...flight instrument using a power supply must have—...

2013-01-01

320

14 CFR 29.1331 - Instruments using a power supply.  

Code of Federal Regulations, 2012 CFR

... Instruments using a power supply. 29.1331 Section...DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS... Instruments using a power supply. For category A rotorcraft...flight instrument using a power supply must have—...

2012-01-01

321

14 CFR 29.1331 - Instruments using a power supply.  

Code of Federal Regulations, 2010 CFR

... Instruments using a power supply. 29.1331 Section...DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS... Instruments using a power supply. For category A rotorcraft...flight instrument using a power supply must have—...

2010-01-01

322

Aircraft ground vibration testing at the NASA Dryden Flight Research Facility, 1993  

NASA Technical Reports Server (NTRS)

The NASA Dryden Flight Research Facility performs ground vibration testing to assess the structural characteristics of new and modified research vehicles. This paper updates the research activities, techniques used, and experiences in applying this technology to aircraft since 1987. Test equipment, data analysis methods, and test procedures used for typical test programs are discussed. The data presented illustrate the use of modal test and analysis in flight research programs for a variety of aircraft. This includes a technique to acquire control surface free-play measurements on the X-31 airplane more efficiently, and to assess the effects of structural modifications on the modal characteristics of an F-18 aircraft. In addition, the status and results from current research activities are presented. These data show the effectiveness of the discrete modal filter as a preprocessor to uncouple response measurements into simple single-degree-of-freedom responses, a database for the comparison of different excitation methods on a JetStar airplane, and the effect of heating on modal frequency and damping.

Kehoe, Michael W.; Freudinger, Lawrence C.

1994-01-01

323

Theseus in Flight  

NASA Technical Reports Server (NTRS)

The Theseus prototype research aircraft shows off its unique design as it flies low over Rogers Dry Lake during a 1996 test flight from NASA's Dryden Flight Research Center, Edwards, California. The Theseus aircraft, built and operated by Aurora Flight Sciences Corporation, Manassas, Virginia, was a unique aircraft flown at NASA's Dryden Flight Research Center, Edwards, California, under a cooperative agreement between NASA and Aurora. Dryden hosted the Theseus program, providing hangar space and range safety for flight testing. Aurora Flight Sciences was responsible for the actual flight testing, vehicle flight safety, and operation of the aircraft. The Theseus remotely piloted aircraft flew its maiden flight on May 24, 1996, at Dryden. During its sixth flight on November 12, 1996, Theseus experienced an in-flight structural failure that resulted in the loss of the aircraft. As of the beginning of the year 2000, Aurora had not rebuilt the aircraft Theseus was built for NASA under an innovative, $4.9 million fixed-price contract by Aurora Flight Sciences Corporation and its partners, West Virginia University, Morgantown, West Virginia, and Fairmont State College, Fairmont, West Virginia. The twin-engine, unpiloted vehicle had a 140-foot wingspan, and was constructed largely of composite materials. Powered by two 80-horsepower, turbocharged piston engines that drove twin 9-foot-diameter propellers, Theseus was designed to fly autonomously at high altitudes, with takeoff and landing under the active control of a ground-based pilot in a ground control station 'cockpit.' With the potential ability to carry 700 pounds of science instruments to altitudes above 60,000 feet for durations of greater than 24 hours, Theseus was intended to support research in areas such as stratospheric ozone depletion and the atmospheric effects of future high-speed civil transport aircraft engines. Instruments carried aboard Theseus also would be able to validate satellite-based global environmental change measurements. Dryden's Project Manager was John Del Frate.

1996-01-01

324

Theseus in Flight  

NASA Technical Reports Server (NTRS)

The twin pusher propeller-driven engines of the Theseus research aircraft can be clearly seen in this photo, taken during a 1996 research flight at NASA's Dryden Flight Research Center, Edwards, California. The Theseus aircraft, built and operated by Aurora Flight Sciences Corporation, Manassas, Virginia, was a unique aircraft flown at NASA's Dryden Flight Research Center, Edwards, California, under a cooperative agreement between NASA and Aurora. Dryden hosted the Theseus program, providing hangar space and range safety for flight testing. Aurora Flight Sciences was responsible for the actual flight testing, vehicle flight safety, and operation of the aircraft. The Theseus remotely piloted aircraft flew its maiden flight on May 24, 1996, at Dryden. During its sixth flight on November 12, 1996, Theseus experienced an in-flight structural failure that resulted in the loss of the aircraft. As of the beginning of the year 2000, Aurora had not rebuilt the aircraft. Theseus was built for NASA under an innovative, $4.9 million fixed-price contract by Aurora Flight Sciences Corporation and its partners, West Virginia University, Morgantown, West Virginia, and Fairmont State College, Fairmont, West Virginia. The twin-engine, unpiloted vehicle had a 140-foot wingspan, and was constructed largely of composite materials. Powered by two 80-horsepower, turbocharged piston engines that drove twin 9-foot-diameter propellers, Theseus was designed to fly autonomously at high altitudes, with takeoff and landing under the active control of a ground-based pilot in a ground control station 'cockpit.' With the potential ability to carry 700 pounds of science instruments to altitudes above 60,000 feet for durations of greater than 24 hours, Theseus was intended to support research in areas such as stratospheric ozone depletion and the atmospheric effects of future high-speed civil transport aircraft engines. Instruments carried aboard Theseus also would be able to validate satellite-based global environmental change measurements. Dryden's Project Manager was John Del Frate.

1996-01-01

325

Theseus in Flight  

NASA Technical Reports Server (NTRS)

The Theseus research aircraft in flight over Rogers Dry Lake, Edwards, California, during a 1996 research flight. The Theseus aircraft, built and operated by Aurora Flight Sciences Corporation, Manassas, Virginia, was a unique aircraft flown at NASA's Dryden Flight Research Center, Edwards, California, under a cooperative agreement between NASA and Aurora. Dryden hosted the Theseus program, providing hangar space and range safety for flight testing. Aurora Flight Sciences was responsible for the actual flight testing, vehicle flight safety, and operation of the aircraft. The Theseus remotely piloted aircraft flew its maiden flight on May 24, 1996, at Dryden. During its sixth flight on November 12, 1996, Theseus experienced an in-flight structural failure that resulted in the loss of the aircraft. As of the beginning of the year 2000, Aurora had not rebuilt the aircraft. Theseus was built for NASA under an innovative, $4.9 million fixed-price contract by Aurora Flight Sciences Corporation and its partners, West Virginia University, Morgantown, West Virginia, and Fairmont State College, Fairmont, West Virginia. The twin-engine, unpiloted vehicle had a 140-foot wingspan, and was constructed largely of composite materials. Powered by two 80-horsepower, turbocharged piston engines that drove twin 9-foot-diameter propellers, Theseus was designed to fly autonomously at high altitudes, with takeoff and landing under the active control of a ground-based pilot in a ground control station 'cockpit.' With the potential ability to carry 700 pounds of science instruments to altitudes above 60,000 feet for durations of greater than 24 hours, Theseus was intended to support research in areas such as stratospheric ozone depletion and the atmospheric effects of future high-speed civil transport aircraft engines. Instruments carried aboard Theseus also would be able to validate satellite-based global environmental change measurements. Dryden's Project Manager was John Del Frate.

1996-01-01

326

Flight test techniques for low speed airfoil evaluation  

NASA Technical Reports Server (NTRS)

Techniques for in-flight evaluation of new airfoils by modifying a single engine general aviation aircraft and measuring and recording airfoil surface pressures, airfoil wake pressures, and aircraft angle of attack and airspeed are presented. Included are descriptions of the aircraft modifications, instrumentation, data reduction techniques, illustrations of typical results and comments on new equipment for flight test applications.

Hoffmann, M. J.; Gregorek, G. M.; Weislogel, G. S.

1978-01-01

327

Piloted simulator investigation of helicopter control systems effects on handling qualities during instrument flight  

NASA Technical Reports Server (NTRS)

An exploratory piloted simulation was conducted to investigate the effects of the characteristics of helicopter flight control systems on instrument flight handling qualities. This joint FAA/NASA study was motivated by the need to improve instrument flight capability. A near-term objective is to assist in updating the airworthiness criteria for helicopter instrument flight. The experiment consisted of variations of single-rotor helicopter types and levels of stability and control augmentation systems (SCAS). These configurations were evaluated during an omnirange approach task under visual and instrument flight conditions. The levels of SCAS design included a simple rate damping system, collective decoupling plus rate damping, and an attitude command system with collective decoupling. A limited evaluation of stick force versus airspeed stability was accomplished. Some problems were experienced with control system mechanization which had a detrimental effect on longitudinal stability. Pilot ratings, pilot commentary, and performance data related to the task are presented.

Forrest, R. D.; Chen, R. T. N.; Gerdes, R. M.; Alderete, T. S.; Gee, D. R.

1979-01-01

328

The development of an airborne instrumentation computer system for flight test  

NASA Technical Reports Server (NTRS)

Instrumentation interfacing frequently requires the linking of intelligent systems together, as well as requiring the link itself to be intelligent. The airborne instrumentation computer system (AICS) was developed to address this requirement. Its small size, approximately 254 by 133 by 140 mm (10 by 51/4 by 51/2 in), standard bus, and modular board configuration give it the ability to solve instrumentation interfacing and computation problems without forcing a redesign of the entire unit. This system has been used on the F-15 aircraft digital electronic engine control (DEEC) and its follow on engine model derivative (EMD) project and in an OV-1C Mohawk aircraft stall speed warning system. The AICS is presently undergoing configuration for use on an F-104 pace aircraft and on the advanced fighter technology integration (AFTI) F-111 aircraft.

Bever, G. A.

1984-01-01

329

Wireless Sensor Networks for Developmental and Flight Instrumentation  

NASA Technical Reports Server (NTRS)

Wireless sensor networks (WSN) based on the IEEE 802.15.4 Personal Area Network and ZigBee Pro 2007 standards are finding increasing use in home automation and smart energy markets providing a framework for interoperable software. The Wireless Connections in Space Project, funded by the NASA Engineering and Safety Center, is developing technology, metrics and requirements for next-generation spacecraft avionics incorporating wireless data transport. The team from Stennis Space Center and Mobitrum Corporation, working under a NASA SBIR grant, has developed techniques for embedding plug-and-play software into ZigBee WSN prototypes implementing the IEEE 1451 Transducer Electronic Datasheet (TEDS) standard. The TEDS provides meta-information regarding sensors such as serial number, calibration curve and operational status. Incorporation of TEDS into wireless sensors leads directly to building application level software that can recognize sensors at run-time, dynamically instantiating sensors as they are added or removed. The Ames Research Center team has been experimenting with this technology building demonstration prototypes for on-board health monitoring. Innovations in technology, software and process can lead to dramatic improvements for managing sensor systems applied to Developmental and Flight Instrumentation (DFI) aboard aerospace vehicles. A brief overview of the plug-and-play ZigBee WSN technology is presented along with specific targets for application within the aerospace DFI market. The software architecture for the sensor nodes incorporating the TEDS information is described along with the functions of the Network Capable Gateway processor which bridges 802.15.4 PAN to the TCP/IP network. Client application software connects to the Gateway and is used to display TEDS information and real-time sensor data values updated every few seconds, incorporating error detection and logging to help measure performance and reliability in relevant target environments. Test results from our prototype WSN running the Mobitrum software system are summarized and the implications to the scalability and reliability for DFI applications are discussed. Our demonstration system, incorporating sensors for life support system and structural health monitoring is described along with test results obtained by running the demonstration prototype in relevant environments such as the Wireless Habitat Testbed at Johnson Space Center in Houston. An operations concept for improved sensor process flow from design to flight test is outlined specific to the areas of Environmental Control and Life Support System performance characterization and structural health monitoring of human-rated spacecraft. This operations concept will be used to highlight the areas where WSN technology, particularly plug-and-play software based on IEEE 1451, can improve the current process, resulting in significant reductions in the technical effort, overall cost and schedule for providing DFI capability for future spacecraft. RELEASED -

Alena, Richard; Figueroa, Fernando; Becker, Jeffrey; Foster, Mark; Wang, Ray; Gamudevelli, Suman; Studor, George

2011-01-01

330

Flight Evaluation of an Aircraft with Side and Center Stick Controllers and Rate-Limited Ailerons  

NASA Technical Reports Server (NTRS)

As part of an ongoing government and industry effort to study the flying qualities of aircraft with rate-limited control surface actuators, two studies were previously flown to examine an algorithm developed to reduce the tendency for pilot-induced oscillation when rate limiting occurs. This algorithm, when working properly, greatly improved the performance of the aircraft in the first study. In the second study, however, the algorithm did not initially offer as much improvement. The differences between the two studies caused concern. The study detailed in this paper was performed to determine whether the performance of the algorithm was affected by the characteristics of the cockpit controllers. Time delay and flight control system noise were also briefly evaluated. An in-flight simulator, the Calspan Learjet 25, was programmed with a low roll actuator rate limit, and the algorithm was programmed into the flight control system. Side- and center-stick controllers, force and position command signals, a rate-limited feel system, a low-frequency feel system, and a feel system damper were evaluated. The flight program consisted of four flights and 38 evaluations of test configurations. Performance of the algorithm was determined to be unaffected by using side- or center-stick controllers or force or position command signals. The rate-limited feel system performed as well as the rate-limiting algorithm but was disliked by the pilots. The low-frequency feel system and the feel system damper were ineffective. Time delay and noise were determined to degrade the performance of the algorithm.

Deppe, P. R.; Chalk, C. R.; Shafer, M. F.

1996-01-01

331

In-flight adaptive performance optimization (APO) control using redundant control effectors of an aircraft  

NASA Technical Reports Server (NTRS)

Practical application of real-time (or near real-time) Adaptive Performance Optimization (APO) is provided for a transport aircraft in steady climb, cruise, turn descent or other flight conditions based on measurements and calculations of incremental drag from a forced response maneuver of one or more redundant control effectors defined as those in excess of the minimum set of control effectors required to maintain the steady flight condition in progress. The method comprises the steps of applying excitation in a raised-cosine form over an interval of from 100 to 500 sec. at the rate of 1 to 10 sets/sec of excitation, and data for analysis is gathered in sets of measurements made during the excitation to calculate lift and drag coefficients C.sub.L and C.sub.D from two equations, one for each coefficient. A third equation is an expansion of C.sub.D as a function of parasitic drag, induced drag, Mach and altitude drag effects, and control effector drag, and assumes a quadratic variation of drag with positions .delta..sub.i of redundant control effectors i=1 to n. The third equation is then solved for .delta..sub.iopt the optimal position of redundant control effector i, which is then used to set the control effector i for optimum performance during the remainder of said steady flight or until monitored flight conditions change by some predetermined amount as determined automatically or a predetermined minimum flight time has elapsed.

Gilyard, Glenn B. (Inventor)

1999-01-01

332

Program for establishing long-time flight service performance of composite materials in the center wing structure of C-130 aircraft. Phase 5: Flight service and inspection  

NASA Technical Reports Server (NTRS)

Inspections of the C-130 composite-reinforced center wings were conducted over the flight service monitoring period of more than six years. Twelve inspections were conducted on each of the two C-130H airplanes having composite reinforced center wing boxes. Each inspection consisted of visual and ultrasonic inspection of the selective boron-epoxy reinforced center wings which included the inspection of the boron-epoxy laminates and the boron-epoxy reinforcement/aluminum structure adhesive bondlines. During the flight service monitoring period, the two C-130H aircraft accumulated more than 10,000 flight hours and no defects were detected in the inspections over this period. The successful performance of the C-130H aircraft with composite-reinforced center wings allowed the transfer of the responsibilities of inspecting and maintaining these two aircraft to the U. S. Air Force.

Kizer, J. A.

1981-01-01

333

Aerodynamic Parameters of High Performance Aircraft Estimated from Wind Tunnel and Flight Test Data  

NASA Technical Reports Server (NTRS)

A concept of system identification applied to high performance aircraft is introduced followed by a discussion on the identification methodology. Special emphasis is given to model postulation using time invariant and time dependent aerodynamic parameters, model structure determination and parameter estimation using ordinary least squares and mixed estimation methods. At the same time problems of data collinearity detection and its assessment are discussed. These parts of methodology are demonstrated in examples using flight data of the X-29A and X-31A aircraft. In the third example wind tunnel oscillatory data of the F-16XL model are used. A strong dependence of these data on frequency led to the development of models with unsteady aerodynamic terms in the form of indicial functions. The paper is completed by concluding remarks.

Klein, Vladislav; Murphy, Patrick C.

1999-01-01

334

Flight service evaluation of Kevlar-49 epoxy composite panels in wide-bodies commercial transport aircraft  

NASA Technical Reports Server (NTRS)

Kevlar-49 fairing panels, installed as flight service components on three L-1011s, were inspected after 9 years of service. There are six Kevlar-49 panels on each aircraft: a left hand and right hand set of a wing body sandwich fairing; a solid laminate under wing fillet panel; and a 422 K (300 F) service aft engine fairing. The fairings have accumulated a total of 70,000 hours, with one ship set having over 24,000 hours service. The Kevlar-49 components were found to be performing satisfactorily in service with no major problems, or any condition requiring corrective action. The only defects noted were minor impact damage, a few minor disbonds and a minor degree of fastener hole fraying and elongation. These are for the most part comparable to damage noted on fiberglass fairings. The service history to date indicates that Kevlar-49 epoxy composite materials have satisfactory service characteristics for use in aircraft secondary structure.

Stone, R. H.

1983-01-01

335

Estimation of longitudinal stability and control derivatives for an icing research aircraft from flight data  

NASA Technical Reports Server (NTRS)

The results of applying a modified stepwise regression algorithm and a maximum likelihood algorithm to flight data from a twin-engine commuter-class icing research aircraft are presented. The results are in the form of body-axis stability and control derivatives related to the short-period, longitudinal motion of the aircraft. Data were analyzed for the baseline (uniced) and for the airplane with an artificial glaze ice shape attached to the leading edge of the horizontal tail. The results are discussed as to the accuracy of the derivative estimates and the difference between the derivative values found for the baseline and the iced airplane. Additional comparisons were made between the maximum likelihood results and the modified stepwise regression results with causes for any discrepancies postulated.

Batterson, James G.; Omara, Thomas M.

1989-01-01

336

Aerodynamic Parameters of High Performance Aircraft Estimated from Wind Tunnel and Flight Test Data  

NASA Technical Reports Server (NTRS)

A concept of system identification applied to high performance aircraft is introduced followed by a discussion on the identification methodology. Special emphasis is given to model postulation using time invariant and time dependent aerodynamic parameters, model structure determination and parameter estimation using ordinary least squares an mixed estimation methods, At the same time problems of data collinearity detection and its assessment are discussed. These parts of methodology are demonstrated in examples using flight data of the X-29A and X-31A aircraft. In the third example wind tunnel oscillatory data of the F-16XL model are used. A strong dependence of these data on frequency led to the development of models with unsteady aerodynamic terms in the form of indicial functions. The paper is completed by concluding remarks.

Klein, Vladislav; Murphy, Patrick C.

1998-01-01

337

Flight study of on-board enhanced vision system for all-weather aircraft landing  

NASA Astrophysics Data System (ADS)

On-board enhanced vision system for all-weather aircraft navigation and landing which is currently under development in State research institute of aviation systems is described. The system is based on combination of three imagers sensitive in visible, short wave infrared (SWIR) and long wave infrared (LWIR) spectral ranges and demonstrating to the pilot only the most informative images from the time-aligned multi-sensor data. The results of flight tests at glissade trajectories of the light aircraft OR-5 MO obtained at various weather conditions are presented. It is shown that each spectral range may be informative under certain conditions of observation. In adverse and poor-visibility conditions, such as fog, high humidity and low clouds, SWIR range has the biggest information content.

Akopdjanan, Yuri A.; Machikhin, Alexander S.; Bilanchuk, Vyacheslav V.; Drynkin, Vladimir N.; Falkov, Eduard Y.; Tsareva, Tatiana I.; Fomenko, Anatoly I.

2014-11-01

338

Flight service evaluation of kevlar-49 epoxy composite panels in wide-bodied commercial transport aircraft: Flight service report  

NASA Technical Reports Server (NTRS)

Kevlar-49 fairing panels, installed as flight service components on three L-1011s, were inspected after 7 years service. There are six Kevlar-49 panels on each aircraft: a left hand and right hand set of a wing-body sandwich fairing; a slid laminate under-wing fillet panel; and a 422 K service aft engine fairing. The three L-1011s include one each in service with Eastern, Air Canada, and TWA. The fairings have accumulated a total of 52,500 hours, with one ship set having 17.700 hours service. The inspections were conducted at the airlines' major maintenance bases with the participation of Lockheed Engineering. The Kevlar-49 components were found to be performing satisfactorily in service with no major problems or any condition requiring corrective action. The only defects noted were minor impact damage and a minor degree of fastener hole fraying and elongation. These are for the most part comparable to damage noted on fiberglass fairings. The service history to date indicates that Kevlar-49 epoxy composite materials have satisfactory service characteristics for use in aircraft secondary structure.

Stone, R. H.

1981-01-01

339

Flight service evaluation of Kevlar-49 epoxy composite panels in wide-bodied commercial transport aircraft  

NASA Technical Reports Server (NTRS)

Kevlar-49 fairing panels, installed as flight service components on three l-1011's, were inspected after 8 years service. The fairings had accumulated a total of 62,000 hours, with one ship set having 20,850 hours service. Kevlar-49 components were found to be performing satisfactorily in service with no major problems. The only defects noted were minor impact damage, a few minor disbonds and a minor degree of fastener hole fraying and elongation. The service history to date indicates that Kevlar-49 epoxy composite materials have satisfactory service characteristics for use in aircraft secondary structures.

Stone, R. H.

1982-01-01

340

19 CFR 10.183 - Duty-free entry of civil aircraft, aircraft engines, ground flight simulators, parts, components...  

Code of Federal Regulations, 2014 CFR

...2014-04-01 2014-04-01 false Duty-free entry of civil aircraft, aircraft...THE TREASURY ARTICLES CONDITIONALLY FREE, SUBJECT TO A REDUCED RATE, ETC... Civil Aircraft § 10.183 Duty-free entry of civil aircraft,...

2014-04-01

341

STS-93 Commander Collins and daughter prepare to board aircraft for return flight to Houston  

NASA Technical Reports Server (NTRS)

At the Skid Strip at the Cape Canaveral Air Station, Commander Eileen Collins and her daughter, Bridget Youngs, prepare to board an aircraft for their return flight to Houston following the completion of the STS-93 Space Shuttle mission. Landing occurred on runway 33 at KSC's Shuttle Landing Facility on July 27 with main gear touchdown at 11:20:35 p.m. EDT. The mission's primary objective was to deploy the Chandra X-ray Observatory, which will allow scientists from around the world to study some of the most distant, powerful and dynamic objects in the universe. This was the 95th flight in the Space Shuttle program and the 26th for Columbia. The landing was the 19th consecutive Shuttle landing in Florida and the 12th night landing in Shuttle program history. On this mission, Collins became the first woman to serve as a Shuttle commander.

1999-01-01

342

STS-93 Commander Collins and daughter prepare to board aircraft for return flight to Houston  

NASA Technical Reports Server (NTRS)

At the Skid Strip at the Cape Canaveral Air Station, Commander Eileen Collins and her daughter Bridget Youngs prepare to board an aircraft for their return flight to Houston following the completion of the STS-93 Space Shuttle mission. Landing occurred on runway 33 at KSC's Shuttle Landing Facility with main gear touchdown at 11:20:35 p.m. EDT on July 27. The mission's primary objective was to deploy the Chandra X-ray Observatory, which will allow scientists from around the world to study some of the most distant, powerful and dynamic objects in the universe. This was the 95th flight in the Space Shuttle program and the 26th for Columbia. The landing was the 19th consecutive Shuttle landing in Florida and the 12th night landing in Shuttle program history. On this mission, Collins became the first woman to serve as a Shuttle commander.

1999-01-01

343

A safety margin and flight reference system and display for powered-lift aircraft  

NASA Technical Reports Server (NTRS)

A study was conducted to explore the feasibility of a safety margin and flight reference system for those powered-lift aircraft which require a backside piloting technique. The main objective was to display multiple safety margin criteria as a single variable which could be tracked both manually and automatically and which could be monitored in order to derive safety margin status. The study involved a pilot-in-the-loop analysis of several system concepts and a simulator experiment to evaluate those concepts showing promise. A system was ultimately configured which yielded reasonable compromises in controllability, status information content, and the ability to regulate safety margins at some expense of the allowable low speed flight path envelope.

Heffley, R. K.; Hardy, G. H.

1978-01-01

344

Flight service evaluation of PRD-49/epoxy composite panels in wide-bodied commercial transport aircraft  

NASA Technical Reports Server (NTRS)

Fairing panels were fabricated to evaluate the fabrication characteristics and flight service performance of PRD-49 (Kevlar-49) a composite reinforcing material and to compare it with the fiberglass which is currently in use. Panel configurations were selected to evaluate the PRD-49 with two resin matrix materials in sandwich and solid laminate construction. Left and right hand versions of these configurations were installed on L-1011's which will accumulate approximately 3000 flight hours per year per aircraft. The direct substitution of PRD-49 for fiberglass produced a twenty-six percent weight reduction on the panel configurations. Examination of these panels revealed that there was no visible difference between the PRD-49 and adjacent fiberglass panels.

Wooley, J. H.

1974-01-01

345

NUVU: handheld instruments for video inspection of aircraft wiring  

NASA Astrophysics Data System (ADS)

Most of the current practices of manual visual inspection of aircraft wiring bundles can be replaced or assisted by a portable test system consisting of a miniature B/W or color TV camera and controllable uniform illumination mounted in a flashlight-sized, hand-held unit weighing less than one pound. The location and configuration of the battery power supply and image viewing and storage means are at the discretion of the inspector. A typical viewed area is nominally 1 inch by 1.3 inches, with a depth of field up to 1.5 inches. Tradeoffs among pixel dimensions, geometrical optics, and lens diffraction which arise in the design of such a unit are discussed. Data are presented showing actuator measured depths of field and image resolutions vs. variable camera lens aperture under real conditions. The image size in these tests provided an overall 12X enlargement of the target, as viewed by the inspector in real time. On insulated wires as small as 1mm OD, printed markings are easily seen and read, as are common chafes, radial surface cracks, and other surface anomalies of the insulation. The present mechanical design permits the small unit not only to inspect areas in any direction to which the hand and wrist can point, but also allows insertion of the unit in areas not easily accessible to the hand or eye.

Pike, John N.; Mehrotra, Yogesh; Kaplan, Herbert

1999-01-01

346

Development of TPS flight test and operational instrumentation  

NASA Technical Reports Server (NTRS)

Thermal and flow sensor instrumentation was developed for use as an integral part of the space shuttle orbiter reusable thermal protection system. The effort was performed in three tasks: a study to determine the optimum instruments and instrument installations for the space shuttle orbiter RSI and RCC TPS; tests and/or analysis to determine the instrument installations to minimize measurement errors; and analysis using data from the test program for comparison to analytical methods. A detailed review of existing state of the art instrumentation in industry was performed to determine the baseline for the departure of the research effort. From this information, detailed criteria for thermal protection system instrumentation were developed.

Carnahan, K. R.; Hartman, G. J.; Neuner, G. J.

1975-01-01

347

Instrumentation and Performance Analysis Plans for the HIFiRE Flight 2 Experiment  

NASA Technical Reports Server (NTRS)

Supersonic combustion performance of a bi-component gaseous hydrocarbon fuel mixture is one of the primary aspects under investigation in the HIFiRE Flight 2 experiment. In-flight instrumentation and post-test analyses will be two key elements used to determine the combustion performance. Pre-flight computational fluid dynamics (CFD) analyses provide valuable information that can be used to optimize the placement of a constrained set of wall pressure instrumentation in the experiment. The simulations also allow pre-flight assessments of performance sensitivities leading to estimates of overall uncertainty in the determination of combustion efficiency. Based on the pre-flight CFD results, 128 wall pressure sensors have been located throughout the isolator/combustor flowpath to minimize the error in determining the wall pressure force at Mach 8 flight conditions. Also, sensitivity analyses show that mass capture and combustor exit stream thrust are the two primary contributors to uncertainty in combustion efficiency.

Gruber, Mark; Barhorst, Todd; Jackson, Kevin; Eklund, Dean; Hass, Neal; Storch, Andrea M.; Liu, Jiwen

2009-01-01

348

Lessons Learned from Numerical Simulations of the F-16XL Aircraft at Flight Conditions  

NASA Technical Reports Server (NTRS)

Nine groups participating in the Cranked Arrow Wing Aerodynamics Project International (CAWAPI) project have contributed steady and unsteady viscous simulations of a full-scale, semi-span model of the F-16XL aircraft. Three different categories of flight Reynolds/Mach number combinations were computed and compared with flight-test measurements for the purpose of code validation and improved understanding of the flight physics. Steady-state simulations are done with several turbulence models of different complexity with no topology information required and which overcome Boussinesq-assumption problems in vortical flows. Detached-eddy simulation (DES) and its successor delayed detached-eddy simulation (DDES) have been used to compute the time accurate flow development. Common structured and unstructured grids as well as individually-adapted unstructured grids were used. Although discrepancies are observed in the comparisons, overall reasonable agreement is demonstrated for surface pressure distribution, local skin friction and boundary velocity profiles at subsonic speeds. The physical modeling, steady or unsteady, and the grid resolution both contribute to the discrepancies observed in the comparisons with flight data, but at this time it cannot be determined how much each part contributes to the whole. Overall it can be said that the technology readiness of CFD-simulation technology for the study of vehicle performance has matured since 2001 such that it can be used today with a reasonable level of confidence for complex configurations.

Rizzi, Arthur; Jirasek, Adam; Lamar, John; Crippa, Simone; Badcock, Kenneth; Boelens, Oklo

2009-01-01

349

Icing effects on aircraft stability and control determined from flight data: Preliminary results  

NASA Technical Reports Server (NTRS)

The effects of airframe icing on the stability and control characteristics of the NASA DH-6 Twin Otter icing research aircraft were investigated by flight test. The flight program was developed to obtain the stability and control parameters of the DH-6 in a baseline ('uniced') configuration and an 'artificially iced' configuration for specified thrust conditions. Stability and control parameter identification maneuvers were performed over a wide range of angles of attack for wing flaps retracted (0 deg) and wing flaps partially deflected (10 deg). Engine power was adjusted to hold thrust constant at one of three thrust coefficients (C(sub T) = 0.14, C(sub T) = 0.07, C(subT) = 0.00). This paper presents only the pitching- and yawing-moment results from the flight test program. Stability and control parameters were estimated for the uniced and artificially iced configurations using a modified stepwise regression algorithm. Comparisons of the uniced and iced stability and control parameters are presented for the majority of the flight envelope. The artificial ice reduced the elevator and rudder control effectiveness by 12 percent and 8 percent respectively for the 0 deg flap setting. The longitudinal static stability was also decreased substantially (approximately 10 percent) because of the tail ice. Further discussion is provided to explain some of the effects of ice on the stability and control parameters.

Ratvasky, T. P.; Ranaudo, R. J.

1993-01-01

350

Icing effects on aircraft stability and control determined from flight data - Preliminary results  

NASA Technical Reports Server (NTRS)

The effects of airframe icing on the stability and control characteristics of the NASA DH-6 Twin Otter icing research aircraft were investigated by flight test. The flight program was developed to obtain stability and control parameters of the DH-6 in a baseline ('uniced') configuration and an 'artificially iced' configuration for specified thrust conditions. Stability and control parameter identification maneuvers were performed over a wide range of angles of attack for wing flaps retraced (0 deg) and wing flaps partially deflected (10 deg). Engine power was adjusted to hold thrust constant at one of three thrust coefficients (C(sub T) = 0.14, C(sub T) = 0.07, C(sub T) = 0.00). This paper presents only the pitching- and yawing-moment results from the flight test program. Stability and control parameters were estimated for the uniced and artificially iced configurations using a modified stepwise regression algorithm. Comparisons of the uniced and iced stability and control parameters are presented for the majority of the flight envelope. The artificial ice reduced the elevator and rudder control effectiveness by 12 percent and 8 percent respectively for the 0 deg flap setting. The longitudinal static stability was also decreased substantially (approximately 10 percent) because of the tail ice. Further discussion is provided to explain some of the effects of ice on the stability and control parameters.

Ratvasky, T. P.; Ranaudo, R. J.

1993-01-01

351

Shift in arm-pointing movements during gravity changes produced by aircraft parabolic flight.  

PubMed

It has been shown that target-pointing arm movements without visual feedback shift downward in space microgravity and upward in centrifuge hypergravity. Under gravity changes in aircraft parabolic flight, however, arm movements have been reported shifting upward in hypergravity as well, but a downward shift under microgravity is contradicted. In order to explain this discrepancy, we reexamined the pointing movements using an experimental design which was different from prior ones. Arm-pointing movements were measured by goniometry around the shoulder joint of subjects with and without eyes closed or with a weight in the hand, during hyper- and microgravity in parabolic flight. Subjects were fastened securely to the seat with the neck fixed and the elbow maintained in an extended position, and the eyes were kept closed for a period of time before each episode of parabolic flight. Under these new conditions, the arm consistently shifted downward during microgravity and mostly upward during hypergravity, as expected. We concluded that arm-pointing deviation induced by parabolic flight could be also be valid for studying the mechanism underlying disorientation under varying gravity conditions. PMID:11542494

Chen, Y; Mori, S; Koga, K; Ohta, Y; Wada, Y; Tanaka, M

1999-06-01

352

Cockpit simulation study of use of flight path angle for instrument approaches  

NASA Technical Reports Server (NTRS)

The results of a piloted simulation experiment to evaluate the effect of integrating flight path angle information into a typical transport electronic attitude director indicator display format for flight director instrument landing system approaches are presented. Three electronic display formats are evaluated during 3 deg straight-in approaches with wind shear and turbulence conditions. Flight path tracking data and pilot subjective comments are analyzed with regard to the pilot's tracking performance and workload for all three display formats.

Hanisch, B.; Ernst, H.; Johnston, R.

1981-01-01

353

Performance of Helicopter Pilots During Inadvertent Flight Into Instrument Meteorological Conditions  

Microsoft Academic Search

Inadvertent flight into instrument meteorological conditions (IMC) is a major cause of general aviation accidents. However, performance of helicopter pilots during inadvertent IMC encounters has not been investigated. We developed objective methods to quantify helicopter pilot effort and performance and applied these to simulated flight into IMC. Results showed strong effects of visibility and weaker effects of altitude and airspeed.

Michael A. Crognale; William K. Krebs

2011-01-01

354

Flight test evaluation of predicted light aircraft drag, performance, and stability  

NASA Technical Reports Server (NTRS)

A technique was developed which permits simultaneous extraction of complete lift, drag, and thrust power curves from time histories of a single aircraft maneuver such as a pullup (from V sub max to V sub stall) and pushover (to sub V max for level flight.) The technique is an extension to non-linear equations of motion of the parameter identification methods of lliff and Taylor and includes provisions for internal data compatibility improvement as well. The technique was show to be capable of correcting random errors in the most sensitive data channel and yielding highly accurate results. This technique was applied to flight data taken on the ATLIT aircraft. The drag and power values obtained from the initial least squares estimate are about 15% less than the 'true' values. If one takes into account the rather dirty wing and fuselage existing at the time of the tests, however, the predictions are reasonably accurate. The steady state lift measurements agree well with the extracted values only for small values of alpha. The predicted value of the lift at alpha = 0 is about 33% below that found in steady state tests while the predicted lift slope is 13% below the steady state value.

Smetana, F. O.; Fox, S. R.

1979-01-01

355

Application of linear subspace stabilization and linear adaptive techniques to aircraft flight control problems. II. The outer loop  

Microsoft Academic Search

For pt. I see ibid., p.146-50. Robust flight control laws are developed for a combat aircraft. The control problem is layered into an outer-loop of control, or automatic pilot, controlling motion of the center of gravity of the aircraft and an inner-loop of control that controls the angular motion around the center of gravity. This paper is concerned with application

C. Tournes; C. D. Johnson

1998-01-01

356

Emergency in-flight egress opening for general aviation aircraft. [pilot bailout  

NASA Technical Reports Server (NTRS)

An emergency in-flight egress system was installed in a light general aviation airplane. The airplane had no provision for egress on the left side. To avoid a major structural redesign for a mechanical door, an add on 11.2 kg (24.6 lb) pyrotechnic-actuated system was developed to create an opening in the existing structure. The skin of the airplane was explosively severed around the side window, across a central stringer, and down to the floor, creating an opening of approximately 76 by 76 cm. The severed panel was jettisoned at an initial velocity of approximately 13.7 m/sec. System development included a total of 68 explosive severance tests on aluminum material using small samples, small and full scale flat panel aircraft structural mockups, and an actual aircraft fuselage. These tests proved explosive sizing/severance margins, explosive initiation, explosive product containment, and system dynamics. This technology is applicable to any aircraft of similar construction.

Bement, L. J.

1980-01-01

357

Robustness Analysis and Reliable Flight Regime Estimation of an Integrated Resilent Control System for a Transport Aircraft  

NASA Technical Reports Server (NTRS)

Formal robustness analysis of aircraft control upset prevention and recovery systems could play an important role in their validation and ultimate certification. As a part of the validation process, this paper describes an analysis method for determining a reliable flight regime in the flight envelope within which an integrated resilent control system can achieve the desired performance of tracking command signals and detecting additive faults in the presence of parameter uncertainty and unmodeled dynamics. To calculate a reliable flight regime, a structured singular value analysis method is applied to analyze the closed-loop system over the entire flight envelope. To use the structured singular value analysis method, a linear fractional transform (LFT) model of a transport aircraft longitudinal dynamics is developed over the flight envelope by using a preliminary LFT modeling software tool developed at the NASA Langley Research Center, which utilizes a matrix-based computational approach. The developed LFT model can capture original nonlinear dynamics over the flight envelope with the ! block which contains key varying parameters: angle of attack and velocity, and real parameter uncertainty: aerodynamic coefficient uncertainty and moment of inertia uncertainty. Using the developed LFT model and a formal robustness analysis method, a reliable flight regime is calculated for a transport aircraft closed-loop system.

Shin, Jong-Yeob; Belcastro, Christine

2008-01-01

358

Flying the North American Adirondack whitetail on instruments  

Microsoft Academic Search

We compare ecosystem-based wildlife management to instrument flight of aircraft. Airplanes cannot be controlled without visual ground reference, or if this is impossible to a cluster of flight instruments. Instrument pilots are trained to develop a rhythmic scan of the cluster to monitor and correct flight path and attitude. The untrained tendency is to fixate on a single gauge. Then,

Richard W. Sage; Bernard C. Patten; Paulette A. Salmon

2003-01-01

359

Modeling of Aircraft Unsteady Aerodynamic Characteristics/Part 3 - Parameters Estimated from Flight Data. Part 3; Parameters Estimated from Flight Data  

NASA Technical Reports Server (NTRS)

A nonlinear least squares algorithm for aircraft parameter estimation from flight data was developed. The postulated model for the analysis represented longitudinal, short period motion of an aircraft. The corresponding aerodynamic model equations included indicial functions (unsteady terms) and conventional stability and control derivatives. The indicial functions were modeled as simple exponential functions. The estimation procedure was applied in five examples. Four of the examples used simulated and flight data from small amplitude maneuvers to the F-18 HARV and X-31A aircraft. In the fifth example a rapid, large amplitude maneuver of the X-31 drop model was analyzed. From data analysis of small amplitude maneuvers ft was found that the model with conventional stability and control derivatives was adequate. Also, parameter estimation from a rapid, large amplitude maneuver did not reveal any noticeable presence of unsteady aerodynamics.

Klein, Vladislav; Noderer, Keith D.

1996-01-01

360

14 CFR 91.205 - Powered civil aircraft with standard category U.S. airworthiness certificates: Instrument and...  

Code of Federal Regulations, 2014 CFR

...anticollision light system, operations...electric landing light... (d) Instrument flight rules...suitable RNAV system. When the DME or RNAV system required...intended landing where repairs...operations are the instruments and...

2014-01-01

361

14 CFR 91.205 - Powered civil aircraft with standard category U.S. airworthiness certificates: Instrument and...  

Code of Federal Regulations, 2010 CFR

...anticollision light system, operations...electric landing light... (d) Instrument flight rules...suitable RNAV system. When the DME or RNAV system required...intended landing where repairs...operations are the instruments and...

2010-01-01

362

14 CFR 91.205 - Powered civil aircraft with standard category U.S. airworthiness certificates: Instrument and...  

Code of Federal Regulations, 2012 CFR

...anticollision light system, operations...electric landing light... (d) Instrument flight rules...suitable RNAV system. When the DME or RNAV system required...intended landing where repairs...operations are the instruments and...

2012-01-01

363

14 CFR 91.205 - Powered civil aircraft with standard category U.S. airworthiness certificates: Instrument and...  

Code of Federal Regulations, 2013 CFR

...anticollision light system, operations...electric landing light... (d) Instrument flight rules...suitable RNAV system. When the DME or RNAV system required...intended landing where repairs...operations are the instruments and...

2013-01-01

364

14 CFR 91.205 - Powered civil aircraft with standard category U.S. airworthiness certificates: Instrument and...  

Code of Federal Regulations, 2011 CFR

...anticollision light system, operations...electric landing light... (d) Instrument flight rules...suitable RNAV system. When the DME or RNAV system required...intended landing where repairs...operations are the instruments and...

2011-01-01

365

Aircraft automatic digital flight control system with inversion of the model in the feed-forward path  

NASA Technical Reports Server (NTRS)

A full-flight-envelope automatic trajectory control system concept is being investigated at Ames Research Center. This concept was developed for advanced aircraft configurations with severe nonlinear characteristics. A feature of the system is an inverse of the complete nonlinear aircraft model as part of the feed-forward control path. Simulation and flight tests have been reported at previous Digital Avionics Systems conferences. A new method for the continuous real-time inversion of the aircraft model using a Newton-Raphson trim algorithm instead of the original inverse table look-up procedure has been developed. The results of a simulation study of a vertical attitude takeoff and landing aircraft using the new inversion technique are presented. Maneuvers were successfully carried out in all directions in the vertical-attitude hover mode. Transition runs from conventional flight through the region of lift-curve-slope reversal at an angle of attack of about 32 deg and to hover at zero speed in the vertical attitude showed satisfactory transient response. Simulations were also conducted in conventional flight at high subsonic speed in steep climb and with turns up to 4 g. Successful flight tests of the system with the new model-inversion technique in a UH-1H helicopter have recently been carried out.

Smith, G. A.; Meyer, G.

1984-01-01

366

An Overview of NASA's Subsonic Research Aircraft Testbed (SCRAT)  

NASA Technical Reports Server (NTRS)

National Aeronautics and Space Administration Dryden Flight Research Center acquired a Gulfstream III (GIII) aircraft to serve as a testbed for aeronautics flight research experiments. The aircraft is referred to as SCRAT, which stands for SubsoniC Research Aircraft Testbed. The aircraft's mission is to perform aeronautics research; more specifically raising the Technology Readiness Level (TRL) of advanced technologies through flight demonstrations and gathering high-quality research data suitable for verifying the technologies, and validating design and analysis tools. The SCRAT has the ability to conduct a range of flight research experiments throughout a transport class aircraft's flight envelope. Experiments ranging from flight-testing of a new aircraft system or sensor to those requiring structural and aerodynamic modifications to the aircraft can be accomplished. The aircraft has been modified to include an instrumentation system and sensors necessary to conduct flight research experiments along with a telemetry capability. An instrumentation power distribution system was installed to accommodate the instrumentation system and future experiments. An engineering simulation of the SCRAT has been developed to aid in integrating research experiments. A series of baseline aircraft characterization flights has been flown that gathered flight data to aid in developing and integrating future research experiments. This paper describes the SCRAT's research systems and capabilities.

Baumann, Ethan; Hernandez, Joe; Ruhf, John C.

2013-01-01

367

Development of a computer technique for the prediction of transport aircraft flight profile sonic boom signatures. M.S. Thesis  

NASA Technical Reports Server (NTRS)

A new computer technique for the analysis of transport aircraft sonic boom signature characteristics was developed. This new technique, based on linear theory methods, combines the previously separate equivalent area and F function development with a signature propagation method using a single geometry description. The new technique was implemented in a stand-alone computer program and was incorporated into an aircraft performance analysis program. Through these implementations, both configuration designers and performance analysts are given new capabilities to rapidly analyze an aircraft's sonic boom characteristics throughout the flight envelope.

Coen, Peter G.

1991-01-01

368

Flight test investigation of certification issues pertaining to general-aviation-type aircraft with natural laminar flow  

NASA Technical Reports Server (NTRS)

Development of Natural Laminar Flow (NLF) technology for application to general aviation-type aircraft has raised some question as to the adequacy of FAR Part 23 for certification of aircraft with significant NLF. A series of flight tests were conducted with a modified Cessna T210R to allow quantitative comparison of the aircraft's ability to meet certification requirements with significant NLF and with boundary layer transition fixed near the leading edge. There were no significant differences between the two conditions except an increasing in drag, which resulted in longer takeoff distances and reduced climb performance.

Doty, Wayne A.

1990-01-01

369

Near-field noise prediction for aircraft in cruising flight: Methods manual. [laminar flow control noise effects analysis  

NASA Technical Reports Server (NTRS)

Methods for predicting noise at any point on an aircraft while the aircraft is in a cruise flight regime are presented. Developed for use in laminar flow control (LFC) noise effects analyses, they can be used in any case where aircraft generated noise needs to be evaluated at a location on an aircraft while under high altitude, high speed conditions. For each noise source applicable to the LFC problem, a noise computational procedure is given in algorithm format, suitable for computerization. Three categories of noise sources are covered: (1) propulsion system, (2) airframe, and (3) LFC suction system. In addition, procedures are given for noise modifications due to source soundproofing and the shielding effects of the aircraft structure wherever needed. Sample cases, for each of the individual noise source procedures, are provided to familiarize the user with typical input and computed data.

Tibbetts, J. G.

1979-01-01

370

Comparison of Orbiter STS-2 development flight instrumentation data with thermal math model predictions  

NASA Technical Reports Server (NTRS)

Thermal performance verification of Reusable Surface Insulation (RSI) has been accomplished by comparisons of STS-2 Orbiter Flight Test (OFT) data with Thermal Math Model (TMM) predictions. The OFT data was obtained from Development Flight Instrumentation RSI plug and gap thermocouples. Quartertile RSI TMMs were developed using measured flight data for surface temperature and pressure environments. Reference surface heating rates, derived from surface temperature data, were multiplied by gap heating ratios to obtain tile sidewall heating rates. This TMM analysis resulted in good agreement of predicted temperatures with flight data for thermocouples located in the RSI, Strain Isolation Pad, filler bar and structure.

Norman, I.; Rochelle, W. C.; Kimbrough, B. S.; Ritrivi, C. A.; Ting, P. C.; Dotts, R. L.

1982-01-01

371

Assessment of future solid rocket motor flight instrumentation/data needs  

NASA Astrophysics Data System (ADS)

Results of an assessment of a designer's data needs for solid rocket motor instrumentation is described, along with the state-of-the-art and specialized instrumentation used to date. It is determined that solid rocket motor data obtained during static testing does not always agree with flight test data, and more quantitative data is necessary for motor design. The most promising new flight test instrumentation/data techniques for future flight programs are presented: microwave horns, ultrasonics, thermovision, in situ transensors, isotopes, and parachute recovery of flight hardware. It is noted that a development effort (minimum one to two years) and adequate funding will be required to have these concepts available for the design of future solid rocket motors.

Allen, W. L.

1981-07-01

372

Predicting the effects of unmodeled dynamics on an aircraft flight control system design using eigenspace assignment  

NASA Technical Reports Server (NTRS)

When using eigenspace assignment to design an aircraft flight control system, one must first develop a model of the plant. Certain questions arise when creating this model as to which dynamics of the plant need to be included in the model and which dynamics can be left out or approximated. The answers to these questions are important because a poor choice can lead to closed-loop dynamics that are unpredicted by the design model. To alleviate this problem, a method has been developed for predicting the effect of not including certain dynamics in the design model on the final closed-loop eigenspace. This development provides insight as to which characteristics of unmodeled dynamics will ultimately affect the closed-loop rigid-body dynamics. What results from this insight is a guide for eigenstructure control law designers to aid them in determining which dynamics need or do not need to be included and a new way to include these dynamics in the flight control system design model to achieve a required accuracy in the closed-loop rigid-body dynamics. The method is illustrated for a lateral-directional flight control system design using eigenspace assignment for the NASA High Alpha Research Vehicle (HARV).

Johnson, Eric N.; Davidson, John B.; Murphy, Patrick C.

1994-01-01

373

V/STOL tilt rotor research aircraft. Volume 3: Ship 2 instrumentation  

NASA Technical Reports Server (NTRS)

Information covering sensor cables, sensor installation, and sensor calibration for the XV-15 aircraft number 2 is included. For each junction box (J-box) designation there is a schematic of the J-box disconnect harness, instrumentation worksheets which show sensor location, and calibration data sheets for each sensor associated with that J-box. An index of measurement data codes to J-box locations is given in a table. Cross references are given.

1978-01-01

374

V/STOL tilt rotor research aircraft. Volume 2: Ship 1 instrumentation  

NASA Technical Reports Server (NTRS)

Information covering sensor cables, sensor installation, and sensor calibration for the XV-15 aircraft number 1 is included. For each junction box (J-box) designation there is a schematic of the J-box disconnect harness instrumentation worksheets which show sensor location, and calibration data sheets for each sensor associated with that J-box. An index of measurement item codes to J-box locations is given in a table. Cross references are given.

1978-01-01

375

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

NASA Technical Reports Server (NTRS)

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.

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

2012-01-01

376

Development and Calibration of Space Flight Instruments at the University of Bern  

NASA Astrophysics Data System (ADS)

Since more than 40 years the division for Space Research and Planetary Sciences of the Physical Institute of the University of Bern develops space flight instruments, such as mass spectrometers, pressure gauges, laser altimeters, and more. Consequently, space flight instruments developed in Bern or with Bernese participation were flown on multiple space missions, for example GEOS, GIOTTO, ULYSSES, SOHO, ROSETTA, and IBEX. All these instruments need to be tested for functionality upon their different development stages (prototypes and engineering units) and the flight units need to be calibrated. Furthermore, these instruments do also need to be tested for survival regarding vibration, shock and thermal loads. Over the years different facilities have been set up at the Physical Institute of the University of Bern to do such work. This report will present these facilities with special respect to the aspect of calibration.

Scheer, Jürgen A.; Wurz, Peter

2014-05-01

377

X-38 research aircraft - second drop flight from NB-52B mothership  

NASA Technical Reports Server (NTRS)

In the mid-1990's researchers at the NASA Dryden Flight Research Center, Edwards, California, and Johnson Space Center in Houston, Texas, began working actively with the sub-scale X-38 prototype crew return vehicle (CRV). This was an unpiloted lifting body designed at 80 percent of the size of a projected emergency crew return vehicle for the International Space Station. The X-38 and the actual CRV are patterned after a lifting-body shape first employed in the Air Force X-23 (SV-5) program in the mid-1960's and the Air Force-NASA X-24A lifting-body project in the early to mid-1970's. Built by Scaled Composites, Inc., in Mojave, California, and outfitted with avionics, computer systems, and other hardware at Johnson Space Center, two X-38 aircraft were involved in flight research at Dryden beginning in July of 1997. Before that, however, Dryden conducted some 13 flights at a drop zone near California City, California. These tests were done with a 1/6-scale model of the X-38 aircraft to test the parafoil concept that would be employed on the X-38 and the actual CRV. The basic concept is that the actual CRV will use an inertial navigation system together with the Global Positioning System of satellites to guide it from the International Space Station into the Earth's atmosphere. A deorbit engine module will redirect the vehicle from orbit into the atmosphere where a series of parachutes and a parafoil will deploy in sequence to bring the vehicle to a landing, possibly in a field next to a hospital. Flight research at NASA Dryden for the X-38 began with an unpiloted captive carry flight in which the vehicle remained attached to its future launch vehicle, the Dryden B-52 008. There were four captive flights in 1997 and three in 1998, plus the first drop test on March 12, 1998, using the parachutes and parafoil. Further captive and drop tests occurred in 1999, including one on February 6, 1999. Although the X-38 landed safely on the lakebed at Edwards after the March 1998 drop test, there had been some problems with the parafoil. Intermediate parafoil tests at the Army Yuma Proving Grounds in Arizona enabled the project to resolve these problems and resume flight research. In the drop tests, the X-38 vehicles have been autonomous after airlaunch from the B-52. After they deploy the parafoil, they have remained autonomous, but there is also a manual mode which allows control from the ground. The X-38 vehicles (designated V131 and V132) are each 24.5 feet long. The actual CRV to be flown in space is expected to be 30 feet long. This 32-second film clip shows the X-38 vehicle on its second test flight, dropping away for the NB-52B mothership and jettisoning the stabilizing drogue chute door. Included are several shots of the vehicle under its main parachute (parafoil) until it finally touches down on Rogers Dry Lake at Edwards Air Force Base, California.

1999-01-01

378

First flight of the Cloud Detection Lidar Instrument Package  

SciTech Connect

The Cloud Detection Lidar Instrument Package is composed of three instruments: the Cloud Detection Lidar (CDL) and two Wide Field of View (WFOV) cameras. The CDL can be rotated to operate in either a nadir-looking or zenith-looking mode. The WFOV cameras provide imagery to complement the CDL measurements. One camera is fixed at nadir looking and the other at zenith looking. Only one camera may be operational at a time. All instruments were successfully flown in September--November 1995.

Henderson, J.R.; Ledebuhr, A.G.; Cameron, G.; Carter, P.; Hugenberger, R.E.; Kordas, J.F.; Nielsen, D.P.; Stratton, P.; Taylor, B. [Lawrence Livermore National Lab., CA (United States)

1996-03-01

379

Navier-Stokes, flight, and wind tunnel flow analysis for the F/A-18 aircraft  

NASA Technical Reports Server (NTRS)

Computational analysis of flow over the F/A-18 aircraft is presented along with complementary data from both flight and wind tunnel experiments. The computational results are based on the three-dimensional thin-layer Navier-Stokes formulation and are obtained from an accurate surface representation of the fuselage, leading-edge extension (LEX), and the wing geometry. However, the constraints imposed by either the flow solver and/or the complexity associated with the flow-field grid generation required certain geometrical approximations to be implemented in the present numerical model. In particular, such constraints inspired the removal of the empennage and the blocking (fairing) of the inlet face. The results are computed for three different free-stream flow conditions and compared with flight test data of surface pressure coefficients, surface tuft flow, and off-surface vortical flow characteristics that included breakdown phenomena. Excellent surface pressure coefficient correlations, both in terms of magnitude and overall trend, are obtained on the forebody throughout the range of flow conditions. Reasonable pressure agreement was obtained over the LEX; the general correlation tends to improve at higher angles of attack. The surface tuft flow and the off-surface vortex flow structures compared qualitatively well with the flight test results. To evaluate the computational results, a wind tunnel investigation was conducted to determine the effects of existing configurational differences between the flight vehicle and the numerical model on aerodynamic characteristics. In most cases, the geometrical approximations made to the numerical model had very little effect on overall aerodynamic characteristics.

Ghaffari, Farhad

1994-01-01

380

Intelligent adaptive nonlinear flight control for a high performance aircraft with neural networks.  

PubMed

This paper describes the development of a neural network (NN) based adaptive flight control system for a high performance aircraft. The main contribution of this work is that the proposed control system is able to compensate the system uncertainties, adapt to the changes in flight conditions, and accommodate the system failures. The underlying study can be considered in two phases. The objective of the first phase is to model the dynamic behavior of a nonlinear F-16 model using NNs. Therefore a NN-based adaptive identification model is developed for three angular rates of the aircraft. An on-line training procedure is developed to adapt the changes in the system dynamics and improve the identification accuracy. In this procedure, a first-in first-out stack is used to store a certain history of the input-output data. The training is performed over the whole data in the stack at every stage. To speed up the convergence rate and enhance the accuracy for achieving the on-line learning, the Levenberg-Marquardt optimization method with a trust region approach is adapted to train the NNs. The objective of the second phase is to develop intelligent flight controllers. A NN-based adaptive PID control scheme that is composed of an emulator NN, an estimator NN, and a discrete time PID controller is developed. The emulator NN is used to calculate the system Jacobian required to train the estimator NN. The estimator NN, which is trained on-line by propagating the output error through the emulator, is used to adjust the PID gains. The NN-based adaptive PID control system is applied to control three angular rates of the nonlinear F-16 model. The body-axis pitch, roll, and yaw rates are fed back via the PID controllers to the elevator, aileron, and rudder actuators, respectively. The resulting control system has learning, adaptation, and fault-tolerant abilities. It avoids the storage and interpolation requirements for the too many controller parameters of a typical flight control system. Performance of the control system is successfully tested by performing several six-degrees-of-freedom nonlinear simulations. PMID:16649568

Savran, Aydogan; Tasaltin, Ramazan; Becerikli, Yasar

2006-04-01

381

Development of a flight data acquisition system for small unmanned aircraft  

NASA Astrophysics Data System (ADS)

Current developments surrounding the use of unmanned aerial vehicles have produced a need for a high quality data acquisition platform developed specifically a research environment. This work was undertaken to produce such a system that is low cost, extensible, and better supports fixed wing research through the inclusion of a custom vane based air data probe capable of measuring airspeed, angle of attack, and angle of sideslip. This was accomplished by starting with the open source Pixhawk system as the core and then modifying the device firmware and adding sensors to suit the needs of current aerospace research at OSU. An overview of each component of the system is presented, as well as a description of various firmware modifications to the stock Pixhawk system. Tests were then performed on all of the major sensors using bench testing, wind tunnel analysis, and flight maneuvers to determine the final performance of each part of the system. This research shows that all of the critical sensors on the data acquisition platform produce data acceptable for flight research. The accelerometer has been shown to have an overall tolerance of +/-0.0545 m/s², with +/-0.223 deg/s for the gyroscopic sensor, +/-1.32 hPa for the barometric sensor, +/-0.318 m/s for the airspeed sensor, +/-1.65 °C for the outside air temperature sensor, and +/-0.00115 V for the analog to digital converter. The stock calibration curve for the airspeed sensor was determined to be correct to within +/-0.5 in H2O through wind tunnel testing, and an experimental step input analysis on the flow direction vanes showed that worst case steady state error and time to damp are acceptable for the system. Power spectral density and spectral coherence analysis of flight data was used to show that the custom air data probe is capable of following the flight dynamics of a given aircraft to within a 10 percent tolerance across a range of frequencies. Finally, general performance of the system was proven using basic aircraft system identification data collection as a test case.

Hood, Scott

382

Impact of Aircraft Emissions on Reactive Nitrogen over the North Atlantic Flight Corridor Region  

NASA Technical Reports Server (NTRS)

The impact of aircraft emissions on reactive nitrogen in the upper troposphere (UT) and lowermost stratosphere (LS) was estimated using the NO(y)-O3 correlation obtained during the SASS Ozone and NO(x) Experiment (SONEX) carried out over the US continent and North Atlantic Flight Corridor (NAFC) region in October and November 1997. To evaluate the large scale impact, we made a reference NO(y)-O3 relationship in air masses, upon which aircraft emissions were considered to have little impact. For this purpose, the integrated input of NO(x) from aircraft into an air mass along a 10-d back trajectory (DELTA-NO(y)) was calculated based on the ANCAT/EC2 emission inventory. The excess NO(y) (dNO(y)) was calculated from the observed NO(y) and the reference NO(y)-O3 relationship. As a result, a weak positive correlation was found between the dNO(y) and DELTA-NO(y), and dNO(y) and NO(x)/NO(y) values, while no positive correlation between the dNO(y) and CO values was found, suggesting that dNO(y) values can be used as a measure of the NO(x) input from aircraft emissions. The excess NO(y) values calculated from another NO(y)-O3 reference relationship made using in-situ CN data also agreed with these dNO(y) values, within the uncertainties. At the NAFC region (45 N - 60 N), the median value of dNO(y) in the troposphere increased with altitude above 9 km and reached 70 pptv (20% of NO(y)) at 11 km. The excess NO(x) was estimated to be about half of the dNO(y) values, corresponding to 30% of the observed NO(x) level. Higher dNO(y) values were generally found in air masses where O3 = 75 - 125 ppbv, suggesting a more pronounced effect around the tropopause. The median value of dNO(y) in the stratosphere at the NAFC region at 8.5 - 11.5 km was about 120 pptv. The higher dNO(y) values in the LS were probably due to the accumulated effect of aircraft emissions, given the long residence time of affected air in the LS. Similar dNO(y) values were also obtained in air masses sampled over the US continent.

Koike, M.; Kondo, Y.; Ikeda, H.; Gregory, G. L.; Anderson, B. E.; Sachse, G. W.; Blake, D.; Liu, S. C.; Singh, H. B.; Thompson, A.

1999-01-01

383

Full-scale flight and model-scale wind tunnel tests on the nearfield noise characteristics of aircraft propellers  

Microsoft Academic Search

Flight noise tests employing a single engine Cessna T 207 aircraft with an array of wing mounted microphones were conducted to investigate nearfield acoustic characteristics of a 3 blade variable pitch propeller under different operational conditions, varying helical blade tip Mach number, propeller advance ratio, and blade loading. A special technique to minimize the engine exhaust influence on the propeller

H. Heller; M. Kallergis; B. Gehlhar

1985-01-01

384

Real-time aircraft structural damage identification with flight condition variations  

NASA Astrophysics Data System (ADS)

This paper presents a real-time structural damage identification method for aircraft with flight condition variations. The proposed approach begins by identifying the dynamic models under various test conditions from time-domain input/output data. A singular value decomposition technique is then used to characterize and quantify the parameter uncertainties from the identified models. The uncertainty coordinates, corresponding to the identified principal directions, of the identified models are computed, and the residual errors between the identified uncertainty coordinates and the estimated uncertainty coordinates of the health structure are used to identify damage status. A correlation approach is applied to identify damage type and intensity, based on the difference between the identified parameters and the estimated parameters of the healthy structure. The proposed approach is demonstrated by application to the Benchmark Active Controls Technology (BACT) wind-tunnel model.

Lew, Jiann-Shiun; Loh, Chin-Hsiung

2012-04-01

385

Flight service evaluation of PRD-49/epoxy composite panels in wide bodied commercial transport aircraft  

NASA Technical Reports Server (NTRS)

L-1011 aircraft fairing panel configurations were selected as test parts to compare the fabrication, costs and service performance characteristics of PRD-49 and fiberglass. These parts are currently fiberglass reinforced structure and the purpose of this program is to evaluate the results of direct substitution of PRD-49 fabric for the fiberglass. Three ship sets of these panels have been fabricated for a five year flight service evaluation on three L-1011 commercial airlines operating in widely diverse route structures. The standard tools and machining techniques used for fiberglass parts are unacceptable for cutting, trimming, and drilling the tougher PRD-49 fibers. Therefore, a machining development study was undertaken to provide the necessary new tools and machining techniques. After incorporating these new developments in the fabrication and installation of the panels, a manufacturing cost study revealed that the labor hours were only increased by about 12.5 percent.

Wooley, J. H.; Paschal, D. R.; Crilly, E. R.

1973-01-01

386

Enabling Electric Propulsion for Flight - Hybrid Electric Aircraft Research at AFRC  

NASA Technical Reports Server (NTRS)

Advances in electric machine efficiency and energy storage capability are enabling a new alternative to traditional propulsion systems for aircraft. This has already begun with several small concept and demonstration vehicles, and NASA projects this technology will be essential to meet energy and emissions goals for commercial aviation in the next 30 years. In order to raise the Technology Readiness Level of electric propulsion systems, practical integration and performance challenges will need to be identified and studied in the near-term so that larger, more advanced electric propulsion system testbeds can be designed and built. Researchers at NASA Armstrong Flight Research Center are building up a suite of test articles for the development, integration, and validation of these systems in a real world environment.

Clarke, Sean; Lin, Yohan; Kloesel, Kurt; Ginn, Starr

2014-01-01

387

Susceptibility to motion sickness in fish: a parabolic aircraft flight study.  

PubMed

Juvenile swordtail fish and larval cichlids were subjected to parabolic aircraft flights (PAFs) and individually observed. After the PAFs, inner ear otoliths and sensory epithelia were examined on the light microscopical level. Otolith asymmetry (differences in otolith size between the left and the right side) was especially pronounced in those fish, who exhibited a kinetotic behaviour (e.g., spinning movements) during microgravity. This speaks in favour of a theoretical concept according to which susceptibility to space motion sickness in humans may be based on asymmetric inner ear stones. The cell density of sensory epithelia was lower in kinetotic animals as compared to normally swimming fish. Thus, asymmetric otoliths can cause kinetosis in fish during PAFs, but susceptibility to kinetosis may also be based on an aberrative inner ear morphology. PMID:14703672

Hilbig, R; Anken, R H; Bauerle, A; Rahmann, H

2002-07-01

388

An Overview of NASA's SubsoniC Research Aircraft Testbed (SCRAT)  

NASA Technical Reports Server (NTRS)

National Aeronautics and Space Administration Dryden Flight Research Center acquired a Gulfstream III (GIII) aircraft to serve as a testbed for aeronautics flight research experiments. The aircraft is referred to as SCRAT, which stands for SubsoniC Research Aircraft Testbed. The aircraft’s mission is to perform aeronautics research; more specifically raising the Technology Readiness Level (TRL) of advanced technologies through flight demonstrations and gathering high-quality research data suitable for verifying the technologies, and validating design and analysis tools. The SCRAT has the ability to conduct a range of flight research experiments throughout a transport class aircraft’s flight envelope. Experiments ranging from flight-testing of a new aircraft system or sensor to those requiring structural and aerodynamic modifications to the aircraft can be accomplished. The aircraft has been modified to include an instrumentation system and sensors necessary to conduct flight research experiments along with a telemetry capability. An instrumentation power distribution system was installed to accommodate the instrumentation system and future experiments. An engineering simulation of the SCRAT has been developed to aid in integrating research experiments. A series of baseline aircraft characterization flights has been flown that gathered flight data to aid in developing and integrating future research experiments. This paper describes the SCRAT’s research systems and capabilities

Baumann, Ethan; Hernandez, Joe; Ruhf, John

2013-01-01

389

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

NASA Technical Reports Server (NTRS)

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.

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

1981-01-01

390

Flight service evaluation of Kevlar-49 epoxy composite panels in wide-bodied commercial transport aircraft  

NASA Technical Reports Server (NTRS)

Kevlar-49 fairing panels, installed as flight service components on three L-1011s, were inspected after 10 years of service. There are six Kevlar-49 panels on each aircraft: a left-hand and right-hand set of a wing-body sandwich fairing; a solid laminate under-wing fillet panel; and a 422 K (300 F) service aft engine fairing. The three L-1011s include one each in service with Eastern, Air Canada, and TWA. The fairings have accumulated a total of 79,568 hours, with one ship set having nearly 28,000 hours service. The inspections were conducted at the airlines' major maintenance bases with the participation of Lockheed Engineering. The Kevlar-49 components were found to be performing satisfactorily in service with no major problems, or any condition requiring corrective action. The only defects noted were minor impact damage, a few minor disbonds and a minor degree of fastener hole fraying and elongation. These are for the most part comparable to damage noted on fiberglass fairings. The service history obtained in this program indicates that Kevlar-49 epoxy composite materials have satisfactory service characteristics for use in aircraft secondary structure.

Stone, R. H.

1984-01-01

391

A generalized method for the identification of aircraft stability and control derivatives from flight test data.  

NASA Technical Reports Server (NTRS)

This paper discusses the application of a generalized identification method for flight test data analysis. The method is based on the maximum likelihood (ML) criterion and includes output error and equation error methods as special cases. Both the linear and nonlinear models with and without process noise are considered. The flight test data from lateral maneuvers of HL-10 and M2/F3 lifting bodies are processed to determine the lateral stability and control derivatives, instrumentation accuracies and biases. A comparison is made between the results of the output error method and the generalized ML method for M2/F3 data containing gusts. It is shown that better fits to time histories are obtained by using the generalized ML method.

Mehra, R. K.; Stepner, D. E.; Tyler, J. S., Jr.

1972-01-01

392

Knowledge-Based Aircraft Automation: Managers Guide on the use of Artificial Intelligence for Aircraft Automation and Verification and Validation Approach for a Neural-Based Flight Controller  

NASA Technical Reports Server (NTRS)

The ultimate goal of this report was to integrate the powerful tools of artificial intelligence into the traditional process of software development. To maintain the US aerospace competitive advantage, traditional aerospace and software engineers need to more easily incorporate the technology of artificial intelligence into the advanced aerospace systems being designed today. The future goal was to transition artificial intelligence from an emerging technology to a standard technology that is considered early in the life cycle process to develop state-of-the-art aircraft automation systems. This report addressed the future goal in two ways. First, it provided a matrix that identified typical aircraft automation applications conducive to various artificial intelligence methods. The purpose of this matrix was to provide top-level guidance to managers contemplating the possible use of artificial intelligence in the development of aircraft automation. Second, the report provided a methodology to formally evaluate neural networks as part of the traditional process of software development. The matrix was developed by organizing the discipline of artificial intelligence into the following six methods: logical, object representation-based, distributed, uncertainty management, temporal and neurocomputing. Next, a study of existing aircraft automation applications that have been conducive to artificial intelligence implementation resulted in the following five categories: pilot-vehicle interface, system status and diagnosis, situation assessment, automatic flight planning, and aircraft flight control. The resulting matrix provided management guidance to understand artificial intelligence as it applied to aircraft automation. The approach taken to develop a methodology to formally evaluate neural networks as part of the software engineering life cycle was to start with the existing software quality assurance standards and to change these standards to include neural network development. The changes were to include evaluation tools that can be applied to neural networks at each phase of the software engineering life cycle. The result was a formal evaluation approach to increase the product quality of systems that use neural networks for their implementation.

Broderick, Ron

1997-01-01

393

The use of an aircraft test stand for VTOL handling qualities studies. [pilot evaluation of flight controllability  

NASA Technical Reports Server (NTRS)

The VTOL flight tests stand for testing control concepts on the X-14B VSS aircraft in hover, is described. This stand permits realistic and safe piloted evaluation and checkout of various control systems and of parameter variations within each system to determine acceptability to the pilot. Pilots can use it as a practical training tool to practice procedures and flying techniques and become familiar with the aircraft characteristics. Some examples of test experience are given. The test stand allows the X14B to maneuver in hover from centered position + or - 9.7 deg in roll and + or - 9.3 deg in pitch, about + or - 6 deg in yaw, and + or - 15 cm in vertical translation. The unique vertical free flight freedom enables study of liftoffs and landings with power conditions duplicated. The response on the stand agrees well with that measured in free hovering flight, and pilot comments confirm this.

Pauli, F. A.; Corliss, L. D.; Selan, S. D.; Gerdes, R. M.; Gossett, T. D.

1974-01-01

394

NASA Langley Distributed Propulsion VTOL Tilt-Wing Aircraft Testing, Modeling, Simulation, Control, and Flight Test Development  

NASA Technical Reports Server (NTRS)

Control of complex Vertical Take-Off and Landing (VTOL) aircraft traversing from hovering to wing born flight mode and back poses notoriously difficult modeling, simulation, control, and flight-testing challenges. This paper provides an overview of the techniques and advances required to develop the GL-10 tilt-wing, tilt-tail, long endurance, VTOL aircraft control system. The GL-10 prototype's unusual and complex configuration requires application of state-of-the-art techniques and some significant advances in wind tunnel infrastructure automation, efficient Design Of Experiments (DOE) tunnel test techniques, modeling, multi-body equations of motion, multi-body actuator models, simulation, control algorithm design, and flight test avionics, testing, and analysis. The following compendium surveys key disciplines required to develop an effective control system for this challenging vehicle in this on-going effort.

Rothhaar, Paul M.; Murphy, Patrick C.; Bacon, Barton J.; Gregory, Irene M.; Grauer, Jared A.; Busan, Ronald C.; Croom, Mark A.

2014-01-01

395

Stability and Control Estimation Flight Test Results for the SR-71 Aircraft With Externally Mounted Experiments  

NASA Technical Reports Server (NTRS)

A maximum-likelihood output-error parameter estimation technique is used to obtain stability and control derivatives for the NASA Dryden Flight Research Center SR-71A airplane and for configurations that include experiments externally mounted to the top of the fuselage. This research is being done as part of the envelope clearance for the new experiment configurations. Flight data are obtained at speeds ranging from Mach 0.4 to Mach 3.0, with an extensive amount of test points at approximately Mach 1.0. Pilot-input pitch and yaw-roll doublets are used to obtain the data. This report defines the parameter estimation technique used, presents stability and control derivative results, and compares the derivatives for the three configurations tested. The experimental configurations studied generally show acceptable stability, control, trim, and handling qualities throughout the Mach regimes tested. The reduction of directional stability for the experimental configurations is the most significant aerodynamic effect measured and identified as a design constraint for future experimental configurations. This report also shows the significant effects of aircraft flexibility on the stability and control derivatives.

Moes, Timothy R.; Iliff, Kenneth

2002-01-01

396

Meteorologically induced variability of sonic-boom characteristics of supersonic aircraft in cruising flight  

NASA Astrophysics Data System (ADS)

The influence of the meteorological variability on the characteristics of the primary sonic boom emerging from an aircraft in cruising flight is investigated. The sonic-boom propagation is calculated by means of an advanced ray-tracing algorithm which takes meteorological influences into account. Real meteorological situations are considered based on a full 10-year data set in 12- and/or 24-h resolution. Three different climate regions are studied: a mid-latitude coastal sea region, a tropical coastal sea area, and a subpolar land region. Frequency distributions of sonic-boom characteristics such as wave amplitude, rise time, and carpet width are shown for each area, all seasons, and opposing flight directions. It turns out that while variability is low at the ground track, it is high laterally for carpet width or boom amplitude at the outer carpet edges. A correlation analysis is applied which shows specific relationships between meteorological profile parameters and acoustical response. In addition, a meteorological classification is introduced and tested.

Blumrich, Reinhard; Coulouvrat, François; Heimann, Dietrich

2005-08-01

397

Flight Data Reduction of Wake Velocity Measurements Using an Instrumented OV-10 Airplane  

NASA Technical Reports Server (NTRS)

A series of flight tests to measure the wake of a Lockheed C- 130 airplane and the accompanying atmospheric state have been conducted. A specially instrumented North American Rockwell OV-10 airplane was used to measure the wake and atmospheric conditions. An integrated database has been compiled for wake characterization and validation of wake vortex computational models. This paper describes the wake- measurement flight-data reduction process.

Vicroy, Dan D.; Stuever, Robert A.; Stewart, Eric C.; Rivers, Robert A.

1999-01-01

398

Planck early results: First assessment of the Low Frequency Instrument in-flight performance  

E-print Network

The scientific performance of the Planck Low Frequency Instrument (LFI) after one year of in-orbit operation is presented. We describe the main optical parameters and discuss photometric calibration, white noise sensitivity, and noise properties. A preliminary evaluation of the impact of the main systematic effects is presented. For each of the performance parameters, we outline the methods used to obtain them from the flight data and provide a comparison with pre-launch ground assessments, which are essentially confirmed in flight.

Mennella, A; Butler, R C; Curto, A; Cuttaia, F; Davis, R J; Dick, J; Frailis, M; Galeotta, S; Gregorio, A; Kurki-Suonio, H; Lawrence, C R; Leach, S; Leahy, J P; Lowe, S; Maino, D; Mandolesi, N; Maris, M; Mart\\'\\inez-González, E; Meinhold, P R; Morgante, G; Pearson, D; Perrotta, F; Polenta, G; Poutanen, T; Sandri, M; Seiffert, M D; Suur-Uski, A -S; Tavagnacco, D; Terenzi, L; Tomasi, M; Valiviita, J; Villa, F; Watson, R; Wilkinson, A; Zacchei, A; Zonca, A; Aja, B; Artal, E; Baccigalupi, C; Banday, A J; Barreiro, R B; Bartlett, J G; Bartolo, N; Battaglia, P; Bennett, K; Bonaldi, A; Bonavera, L; Borrill, J; Bouchet, F R; Burigana, C; Cabella, P; Cappellini, B; Chen, X; Colombo, L; Cruz, M; Danese, L; D'Arcangelo, O; Davies, R D; de Gasperis, G; de Rosa, A; de Zotti, G; Dickinson, C; Diego, J M; Donzelli, S; Efstathiou, G; En\\sslin, T A; Eriksen, H K; Falvella, M C; Finelli, F; Foley, S; Franceschet, C; Franceschi, E; Gaier, T C; Génova-Santos, R T; George, D; Gómez, F; González-Nuevo, J; Górski, K M; Gruppuso, A; Hansen, F K; Herranz, D; Herreros, J M; Hoyland, R J; Hughes, N; Jewell, J; Jukkala, P; Juvela, M; Kangaslahti, P; Keihänen, E; Keskitalo, R; Kilpia, V -H; Kisner, T S; Knoche, J; Knox, L; Laaninen, M; Lähteenmäki, A; Lamarre, J -M; Leonardi, R; León-Tavares, J; Leutenegger, P; Lilje, P B; López-Caniego, M; Lubin, P M; Malaspina, M; Marinucci, D; Massardi, M; Matarrese, S; Matthai, F; Melchiorri, A; Mendes, L; Miccolis, M; Migliaccio, M; Mitra, S; Moss, A; Natoli, P; Nesti, R; N\\orgaard-Nielsen, H U; Pagano, L; Paladini, R; Paoletti, D; Partridge, B; Pasian, F; Pettorino, V; Pietrobon, D; Pospieszalski, M; Prézeau, G; Prina, M; Procopio, P; Puget, J -L; Quercellini, C; Rachen, J P; Rebolo, R; Reinecke, M; Ricciardi, S; Robbers, G; Rocha, G; Roddis, N; Rubi\; Savelainen, M; Scott, D; Silvestri, R; Simonetto, A; Sjoman, P; Smoot, G F; Sozzi, C; Stringhetti, L; Tauber, J A; Tofani, G; Tuovinen, J; Türler, M; Umana, G; Valenziano, L; Varis, J; Vielva, P; Vittorio, N; Wade, L A; Watson, C; White, S; Winder, F

2011-01-01

399

Planck pre-launch status: Calibration of the Low Frequency Instrument flight model radiometers  

Microsoft Academic Search

The Low Frequency Instrument (LFI) on-board the ESA Planck satellite carries eleven radiometer subsystems, called radiometer chain assemblies (RCAs), each composed of a pair of pseudo-correlation receivers. We describe the on-ground calibration campaign performed to qualify the flight model RCAs and to measure their pre-launch performances. Each RCA was calibrated in a dedicated flight-like cryogenic environment with the radiometer front-end

F. Villa; L. Terenzi; M. Sandri; P. Meinhold; T. Poutanen; P. Battaglia; C. Franceschet; N. Hughes; M. Laaninen; P. Lapolla; M. Bersanelli; R. C. Butler; F. Cuttaia; O. D'Arcangelo; M. Frailis; E. Franceschi; S. Galeotta; A. Gregorio; R. Leonardi; S. R. Lowe; N. Mandolesi; M. Maris; L. Mendes; A. Mennella; G. Morgante; L. Stringhetti; M. Tomasi; L. Valenziano; A. Zacchei; A. Zonca; B. Aja; E. Artal; M. Balasini; T. Bernardino; E. Blackhurst; L. Boschini; B. Cappellini; F. Cavaliere; A. Colin; F. Colombo; R. J. Davis; L. de La Fuente; J. Edgeley; T. Gaier; A. Galtress; R. Hoyland; P. Jukkala; D. Kettle; V.-H. Kilpia; C. R. Lawrence; D. Lawson; J. P. Leahy; P. Leutenegger; S. Levin; D. Maino; M. Malaspina; A. Mediavilla; M. Miccolis; L. Pagan; J. P. Pascual; F. Pasian; M. Pecora; M. Pospieszalski; N. Roddis; M. J. Salmon; M. Seiffert; R. Silvestri; A. Simonetto; P. Sjoman; C. Sozzi; J. Tuovinen; J. Varis; A. Wilkinson; F. Winder

2010-01-01

400

In-Flight Thermal Performance of the Geoscience Laser Altimeter System (GLAS) Instrument  

NASA Technical Reports Server (NTRS)

The Geoscience Laser Altimeter System (GLAS) instrument is NASA Goddard Space Flight Center's first application of Loop Heat Pipe technology that provides selectable/stable temperature levels for the lasers and other electronics over a widely varying mission environment. GLAS was successfully launched as the sole science instrument aboard the Ice, Clouds, and Land Elevation Satellite (ICESat) from Vandenberg AFB at 4:45pm PST on January 12, 2003. After SC commissioning, the LHPs started easily and have provided selectable and stable temperatures for the lasers and other electronics. This paper discusses the thermal development background and testing, along with details of early flight thermal performance data.

Grob, Eric; Baker, Charles; McCarthy, Tom

2003-01-01

401

ET TPS Development Criteria and Flight Instrumentation Program  

NASA Technical Reports Server (NTRS)

The objective was to verify the design thermal environments for the Space Shuttle External Tank. These environments encompassed a myraid of potential flight cases which included nominal and dispersed trajectories launched from Kennedy Space Center (KSC) and Vandenberg and abort cases. Many iterations of environments have been produced during the evolution of the Space Shuttle system which required an analysis and assessment of each environment. A significant effort was expended in the analysis and application of wind tunnel and heat transfer data to develop math/computer models. Various versions of the aeroheating computer code MINIVER were tailored to calculate ascent aeroheating environments for the External Tank. The significant environment assessment results are summarized.

Warmbrod, John D.

1986-01-01

402

Header for SPIE use Alaskan Flight Trials of a Synthetic Vision System  

E-print Network

Header for SPIE use Alaskan Flight Trials of a Synthetic Vision System for Instrument Landings, situational awareness, instrument approach 1. INTRODUCTION Synthetic vision systems for aircraft have been a low-cost prototype synthetic vision system and flight tested it onboard general aviation aircraft

Stanford University

403

Case Study: Test Results of a Tool and Method for In-Flight, Adaptive Control System Verification on a NASA F-15 Flight Research Aircraft  

NASA Technical Reports Server (NTRS)

Adaptive control technologies that incorporate learning algorithms have been proposed to enable autonomous flight control and to maintain vehicle performance in the face of unknown, changing, or poorly defined operating environments [1-2]. At the present time, however, it is unknown how adaptive algorithms can be routinely verified, validated, and certified for use in safety-critical applications. Rigorous methods for adaptive software verification end validation must be developed to ensure that. the control software functions as required and is highly safe and reliable. A large gap appears to exist between the point at which control system designers feel the verification process is complete, and when FAA certification officials agree it is complete. Certification of adaptive flight control software verification is complicated by the use of learning algorithms (e.g., neural networks) and degrees of system non-determinism. Of course, analytical efforts must be made in the verification process to place guarantees on learning algorithm stability, rate of convergence, and convergence accuracy. However, to satisfy FAA certification requirements, it must be demonstrated that the adaptive flight control system is also able to fail and still allow the aircraft to be flown safely or to land, while at the same time providing a means of crew notification of the (impending) failure. It was for this purpose that the NASA Ames Confidence Tool was developed [3]. This paper presents the Confidence Tool as a means of providing in-flight software assurance monitoring of an adaptive flight control system. The paper will present the data obtained from flight testing the tool on a specially modified F-15 aircraft designed to simulate loss of flight control faces.

Jacklin, Stephen A.; Schumann, Johann; Guenther, Kurt; Bosworth, John

2006-01-01

404

Operational performance of vapor-screen systems for in-flight visualization of leading-edge vortices on the F-106B aircraft  

NASA Technical Reports Server (NTRS)

A flight research program was undertaken at the NASA Langley Research Center to apply the vapor-screen technique, widely used in wind tunnels, to an aircraft. The purpose was to obtain qualitative and quantitative information about near-field vortex flows above the wings of fighter aircraft and ascertain the effects of Reynolds and Mach numbers over the angle-of-attack range. The hardware for the systems required for flight application of the vapor-screen technique was successfully developed and integrated. Details of each system, its operational performance on the F-106B aircraft, and pertinent aircraft and environmental data collected are presented.

Lamar, John E.; Bruce, Robert A.; Bruce, Robert A.; Bruce, Robert A.; Bruce, Robert A.; Bruce, Robert A.; Bruce, Robert A.

1987-01-01

405

A perspective on 15 years of proof-of-concept aircraft development and flight research at Ames-Moffett by the Rotorcraft and Powered-Lift Flight Projects Division, 1970-1985  

NASA Technical Reports Server (NTRS)

A proof-of-concept (POC) aircraft is defined and the concept of interest described for each of the six aircraft developed by the Ames-Moffet Rotorcraft and Powered-Lift Flight Projects Division from 1970 through 1985; namely, the OV-10, the C-8A Augmentor Wing, the Quiet Short-Haul Research Aircraft (QSRA), the XV-15 Tilt Rotor Research Aircraft (TRRA), the Rotor Systems Research Aircraft (RSRA)-compound, and the yet-to-fly RSRA/X-Wing Aircraft. The program/project chronology and most noteworthy features of the concepts are reviewed. The paper discusses the significance of each concept and the project demonstrating it; it briefly looks at what concepts are on the horizon as potential POC research aircraft and emphasizes that no significant advanced concept in aviation technology has ever been accepted by civilian or military users without first completing a demonstration through flight testing.

Few, David D.

1987-01-01

406

Estimation of energetic efficiency of heat supply in front of the aircraft at supersonic accelerated flight. Part 1. Mathematical models  

NASA Astrophysics Data System (ADS)

Fuel economy at boost trajectory of the aerospace plane was estimated during energy supply to the free stream. Initial and final flight velocities were specified. The model of a gliding flight above cold air in an infinite isobaric thermal wake was used. The fuel consumption rates were compared at optimal trajectory. The calculations were carried out using a combined power plant consisting of ramjet and liquid-propellant engine. An exergy model was built in the first part of the paper to estimate the ramjet thrust and specific impulse. A quadratic dependence on aerodynamic lift was used to estimate the aerodynamic drag of aircraft. The energy for flow heating was obtained at the expense of an equivalent reduction of the exergy of combustion products. The dependencies were obtained for increasing the range coefficient of cruise flight for different Mach numbers. The second part of the paper presents a mathematical model for the boost interval of the aircraft flight trajectory and the computational results for the reduction of fuel consumption at the boost trajectory for a given value of the energy supplied in front of the aircraft.

Latypov, A. F.

2008-12-01

407

A complementary filtering technique for deriving aircraft velocity and position information. [onboard navigation system and radar tracking signals for instrument landing approach guidance  

NASA Technical Reports Server (NTRS)

An onboard navigation system which employed complementary filtering was developed to provide velocity and position information. The inputs to the mix filter included both acceleration inputs, which provided high-frequency position and velocity information, and radar position inputs, which provided the low-frequency position and velocity information. Onboard aircraft instrumentation, including attitude reference gyros and body-mounted accelerometers, was used to provide the acceleration information. An in-flight comparison of signal quality and accuracy showed good agreement between the complementary filtering system and an aided inertial navigation system. Furthermore, the complementary filtering system was proven to be satisfactory in control and display system applications for both automatic and pilot-in-the-loop instrument approaches and landings.

Niessen, F. R.

1975-01-01

408

Temperature Coefficient of the Modulus of Rigidity of Aircraft Instrument Diaphragm and Spring Materials  

NASA Technical Reports Server (NTRS)

Experimental data are presented on the variation of the modulus of rigidity in the temperature range -20 to +50 degrees C. of a number of metals which are of possible use for elastic elements for aircraft and other instruments. The methods of the torsional pendulum was used to determine the modulus of rigidity and its temperature coefficient for aluminum, duralumin, monel metal, brass, phosphor bronze, coin silver, nickel silver, three high carbon steels, and three alloy steels. It was observed that tensile stress affected the values of the modulus by amounts of 1 per cent or less.

Brombacher, W G; Melton, E R

1931-01-01

409

Reflectron Time-of-Flight Mass Spectrometer (REMAS) Instrumentation  

NASA Technical Reports Server (NTRS)

The restricted mass and power budgets of landed science missions present a challenge to obtaining detailed analyses of planetary bodies. In situ studies, whether alone or as reconnaissance for sample return, must rely on highly miniaturized and autonomous instrumentation. Such devices must still produce useful data sets from a minimum of measurements. The great desire to understand the surfaces and interiors of planets, moons, and small bodies had driven the development of small, robotic techniques with ever-increasing capabilities. One of the most important goals on a surface mission is to study composition in many geological contexts. The mineralogical, molecular, elemental, and isotopic content of near-surface materials (regolith, rocks, soils, dust, etc.) at a variety of sites can complement broader imaging to describe the makeup and formative history of the body in question. Instruments that perform this site-to-site analysis must be highly transportable and work as a suite. For instance, a camera, microscope, spectrophotometer, and mass spectrometer can share several components and operate under a parallel command structure. Efficient use of multiple systems on a small rover has been demonstrated on the Mars Pathfinder mission.

Brinckerhoff, W. B.; McEntire, R. W.; Cheng, A. F.

2000-01-01

410

Propulsion Control and Health Management (PCHM) Technology for Flight Test on the C-17 T-1 Aircraft  

NASA Technical Reports Server (NTRS)

The C-I 7 T-l Globemaster III is an Air Force flight research vehicle located at Edwards Air Force Base. NASA Dryden and the C-17 System Program Office have entered into a Memorandum of Agreement to permit NASA the use of the C-I 7 T-I to conduct flight research on a mutually coordinated schedule. The C-17 Propulsion Control and Health Management (PCHM) Working Group was formed in order to foster discussion and coordinate planning amongst the various government agencies conducting PCHM research with a potential need for flight testing, and to communicate to the PCHM community the capabilities of the C-17 T-l aircraft to support such flight testing. This paper documents the output of this Working Group, including a summary of the candidate PCHM technologies identified and their associated benefits relative to NASA goals and objectives.

Simon, Donald L.; Garg, Sanjay; Venti, Michael

2004-01-01

411

Flight Demonstration of X-33 Vehicle Health Management System Components on the F/A-18 Systems Research Aircraft  

NASA Technical Reports Server (NTRS)

The X-33 reusable launch vehicle demonstrator has identified the need to implement a vehicle health monitoring system that can acquire data that monitors system health and performance. Sanders, a Lockheed Martin Company, has designed and developed a commercial off-the-shelf (COTS)-based open architecture system that implements a number of technologies that have not been previously used in a flight environment. NASA Dryden Flight Research Center and Sanders teamed to demonstrate that the distributed remote health nodes, fiber optic distributed strain sensor, and fiber distributed data interface communications components of the X-33 vehicle health management (VHM) system could be successfully integrated and flown on a NASA F-18 aircraft. This paper briefly describes components of X-33 VHM architecture flown at Dryden and summarizes the integration and flight demonstration of these X-33 VHM components. Finally, it presents early results from the integration and flight efforts.

Schweikhard, Keith A.; Richards, W. Lance; Theisen, John; Mouyos, William; Garbos, Raymond; Schkolnik, Gerald (Technical Monitor)

1998-01-01

412

Flight Demonstration of X-33 Vehicle Health Management System Components on the F/A-18 Systems Research Aircraft  

NASA Technical Reports Server (NTRS)

The X-33 reusable launch vehicle demonstrator has identified the need to implement a vehicle health monitoring system that can acquire data that monitors system health and performance. Sanders, a Lockheed Martin Company, has designed and developed a COTS-based open architecture system that implements a number of technologies that have not been previously used in a flight environment. NASA Dryden Flight Research Center and Sanders teamed to demonstrate that the distributed remote health nodes, fiber optic distributed strain sensor, and fiber distributed data interface communications components of the X-33 vehicle health management (VHM) system could be successfully integrated and flown on a NASA F-18 aircraft. This paper briefly describes components of X-33 VHM architecture flown at Dryden and summarizes the integration and flight demonstration of these X-33 VHM components. Finally, it presents early results from the integration and flight efforts.

Schweikhard, Keith A.; Richards, W. Lance; Theisen, John; Mouyos, William; Garbos, Raymond

2001-01-01

413

THE MARS SCIENCE LABORATORY (MSL) MARS DESCENT IMAGER (MARDI) FLIGHT INSTRUMENT. M. C. Malin1  

E-print Network

algorithms for future autonomous landing and hazard avoidance systems. Although not an original requirementTHE MARS SCIENCE LABORATORY (MSL) MARS DESCENT IMAGER (MARDI) FLIGHT INSTRUMENT. M. C. Malin1 , M , and R. A. Yingst17 , 1 Malin Space Science Systems, PO Box 910148, San Diego CA 92191-0148, 2 Jet

Willson, Reg

414

The Effect of Feedback on the Accuracy of Checklist Completion during Instrument Flight Training  

ERIC Educational Resources Information Center

This study examined whether pilots completed airplane checklists more accurately when they receive postflight graphic and verbal feedback. Participants were 8 college students who are pilots with an instrument rating. The task consisted of flying a designated flight pattern using a personal computer aviation training device (PCATD). The dependent…

Rantz, William G.; Dickinson, Alyce M.; Sinclair, Gilbert A.; Van Houten, Ron

2009-01-01

415

Low-speed wind-tunnel investigation of the flight dynamic characteristics of an advanced turboprop business/commuter aircraft configuration  

NASA Technical Reports Server (NTRS)

An investigation was conducted to determine the low-speed flight dynamic behavior of a representative advanced turboprop business/commuter aircraft concept. Free-flight tests were conducted in the NASA Langley Research Center's 30- by 60-Foot Tunnel. In support of the free-flight tests, conventional static, dynamic, and free-to-roll oscillation tests were performed. Tests were intended to explore normal operating and post stall flight conditions, and conditions simulating the loss of power in one engine.

Coe, Paul L., Jr.; Turner, Steven G.; Owens, D. Bruce

1990-01-01

416

Aircraft Sensor Platform Has Increased Angular Range  

NASA Technical Reports Server (NTRS)

Mechanism rotates and translates instrument platform within pressure housing in aircraft to aim remote-sensing instrument toward target on ground below. Enables instrument to look under aircraft structure at larger fore and aft angles without having to deploy instrument into air stream outside. Also provides 10 degrees of yaw compensation, reducing further need for adjustment of attitude of aircraft to keep target in sight. With yaw compensation, pilot can fly with wings level and nose pointed into crosswind while on desired flight path over target.

Dabney, Philip W.; Bhardwaj, Suneel

1995-01-01

417

Behavioural Adaptation to diminished Gravity in Fish - a Parabolic Aircraft Flight Study  

NASA Astrophysics Data System (ADS)

During the micro gravity phases in the course of parabolic aircraft flights PFs some fish of a given batch were frequently shown to exhibit sensorimotor disorders in terms of revealing so-called looping responses LR or spinning movements SM both forms of motion sickness a kinetosis In order to gain some insights into the time-course of the behavioural adaptation towards diminished gravity in total 272 larval cichlid fish Oreochromis mossambicus were subjected to PFs and their respective behaviour was monitored With the onset of the first parabola P1 15 9 of the animals revealed a kinetotic behaviour whereas kinetoses were shown in 6 5 1 5 and 1 of the animals in P5 P10 and P15 With P20 the animals had adapted completely 0 swimming kinetotically Since the relative decrease of kinetotic animals was especially prominent from P5 to P10 a detailed analysis of the behaviour was undertaken Regarding SM a ratio of 2 9 in P5 decreased to 0 5 in P10 Virtually all individuals showing a SM in P5 had regained a normal behaviour with P10 The SM animals in P10 had all exhibited a normal swimming behaviour in P5 The ratio of LR-fish also decreased from P5 3 6 to P10 1 0 In contrast to the findings regarding SM numerous LM specimens did not regain a normal postural control and only very few animals behaving normally in P5 began to sport a LM behaviour by P10 Summarizing most kinetotic animals rapidly adapted to diminished gravity but few individual fish who swam normally at the beginning of the flights may loose sensorimotor control

Forster, A.; Anken, R.; Hilbig, R.

418

Application of trajectory optimization techniques to upper atmosphere sampling flights using the F4-C Phantom aircraft  

NASA Technical Reports Server (NTRS)

Altitude potential of an off-the-shelf F4-C aircraft is examined. It is shown that the standard F4-C has a maximum altitude capability in the region from 85000 to 95000 ft, depending on the minimum dynamic pressures deemed acceptable for adequate flight control. By using engine overspeed capability and by making use of prevailing winds in the stratosphere, it is suggested that the maximum altitude achievable by an F4-C should be in the vicinity of 95000 ft for routine flight operation. This altitude is well in excess of the minimum altitudes which must be achieved for monitoring the possible growth of suspected aerosol contaminants.

Hague, D. S.; Merz, A. W.

1975-01-01

419

Investigations Using Laboratory Testbeds to Interpret Flight Instrument Datasets from Mars Robotic Missions  

NASA Technical Reports Server (NTRS)

The Astromaterials Research and Exploration Science Directorate at the NASA Johnson Space Center (JSC) has laboratory instrumentation that mimic the capabilities of corresponding flight instruments to enable interpretation of datasets returned from Mars robotic missions. The lab instruments have been and continue to be applied to datasets for the Moessbauer Spectrometer (MB) on the Mars Exploration Rovers (MER), the Thermal & Evolved Gas Analyzer (TEGA) on the Mars Phoenix Scout, the CRISM instrument on the Mars Reconnaissance Orbiter Missions and will be applied to datasets for the Sample Analysis at Mars (SAM), Chemistry and Mineralogy (CheMin) and Chemistry & Camera (ChemCam) instruments onboard the Mars Science Laboratory (MSL). The laboratory instruments can analyze analog samples at costs that are substantially lower than engineering models of flight instruments, but their success to enable interpretation of flight data depends on how closely their capabilities mimic those of the flight instrument. The JSC lab MB instruments are equivalent to the MER instruments except without flight qualified components and no reference channel Co-57 source. Data from analog samples were critical for identification of Mg-Fe carbonate at Gusev crater. Fiber-optic VNIR spectrometers are used to obtain CRISM-like spectral data over the range 350-2500 nm, and data for Fephyllosilicates show irreversible behavior in the electronic transition region upon dessication. The MB and VNIR instruments can be operated within chambers where, for example, the absolute H2O concentration can be measured and controlled. Phoenix's TEGA consisted of a calorimeter coupled to a mass spectrometer (MS). The JSC laboratory testbed instrument consisted of a differential scanning calorimeter (DSC) coupled to a MS configured to operate under total pressure (12 mbar), heating rate (20 C/min), and purge gas composition (N2) analogous to the flight TEGA. TEGA detected CO2 release at both low (400-680 C) and high (725-820 C) temperature and an endothermic reaction in concert with the high temperature release. The high-temperature thermal decomposition is consistent with calcite, dolomite, or ankerite, (3-6 wt.%) or any combination of these phase based upon laboratory testbed experiments. Recent laboratory experiments suggest that the low temperature CO2 release was caused by a reaction between calcium carbonate and hydrated magnesium perchlorate; although, CO2 release by the oxidation of organic materials and Fe-/Mg-rich carbonates cannot be ruled out. MSL landed in Gale crater on August 5, 2012. Although numerous analog samples have been analyzed on the JSC laboratory testbeds, no SAM, CheMin, or ChemCam analyses have been acquired by MSL to date. The JSC SAM laboratory testbed consists of a thermal analyzer coupled with a MS configured to operate under total pressure (30 mbar), heating rate (35 C/min), and purge gas composition (He) analogous to the flight SAM. The CheMin and ChemCam laboratory testbeds were developed and built by inXitu, Inc. and Los Alamos National Laboratory, respectively, to acquire datasets relevant to the MSL CheMin and ChemCam flight instruments.

Ming, D. W.; Morris, R. V.; Sutter, B.; Archer, P. D., Jr.; Achilles, C. N.

2012-01-01

420

Flight experience with advanced controls and displays during piloted curved decelerating approaches in a powered-lift STOL aircraft  

NASA Technical Reports Server (NTRS)

A program to assess the feasibility of piloted STOL approaches along predefined, steep, curved, and decelerating approach profiles was carried out with a powered-lift STOL aircraft. To reduce the pilot workload associated with the basic control requirements of a powered-lift aircraft equipped with redundant controls and operating on the backside of the power curve, separate stability augmentation systems for attitude and speed were provided, as well as a supporting flight director and special electronic cockpit displays. The control, display, and procedural features are described for the flight experiment that led to the conclusion that, given an adequate navigation environment, such constrained approaches may be feasible from a pilot acceptance point of view.

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

1979-01-01

421

Preliminary system design study for a digital fly-by-wire flight control system for an F-8C aircraft  

NASA Technical Reports Server (NTRS)

The design of a fly-by-wire control system having a mission failure probability of less than one millionth failures per flight hour is examined. Emphasis was placed on developing actuator configurations that would improve the system performance, and consideration of the practical aspects of sensor/computer and computer/actuator interface implementation. Five basic configurations were defined as appropriate candidates for the F-8C research aircraft. Options on the basic configurations were included to cover variations in flight sensors, redundancy levels, data transmission techniques, processor input/output methods, and servo actuator arrangements. The study results can be applied to fly by wire systems for transport aircraft in general and the space shuttle.

Seacord, C. L.; Vaughn, D. K.

1976-01-01

422

Simulation model of the integrated flight/propulsion control system, displays, and propulsion system for ASTOVL lift-fan aircraft  

NASA Technical Reports Server (NTRS)

A simulation model has been developed for use in piloted evaluations of takeoff, transition, hover, and landing characteristics of an advanced, short takeoff, vertical landing lift fan fighter aircraft. The flight/propulsion control system includes modes for several response types which are coupled to the aircraft's aerodynamic and propulsion system effectors through a control selector tailored to the lift fan propulsion system. Head-up display modes for approach and hover, tailored to their corresponding control modes are provided in the simulation. Propulsion system components modeled include a remote lift and a lift/cruise engine. Their static performance and dynamic response are represented by the model. A separate report describes the subsonic, power-off aerodynamics and jet induced aerodynamics in hover and forward flight, including ground effects.

Chung, W. Y. William; Borchers, Paul F.; Franklin, James A.

1995-01-01

423

A flight investigation of the wake turbulence alleviation resulting from a flap configuration change on a B-747 aircraft  

NASA Technical Reports Server (NTRS)

A flight test investigation was conducted to evaluate the effects of a flap configuration change on the vortex wake characteristics of a Boeing 747 (B-747) aircraft as measured by differences in upset response resulting from deliberate vortex encounters by a following Learjet aircraft and by direct measurement of the velocities in the wake. The flaps of the B-747 have a predominant effect on the wake. The normal landing flap configuration produces a strong vortex that is attenuated when the outboard flap segments are raised; however, extension of the landing gear at that point increa