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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

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

3

Instrumentation of a light twin aircraft for flow energizer flight tests  

E-print Network

the separated region aft of a wing-body junction. However, no vortex associated with the flow energizer was found at the location where initial surveys were made. The force and moment data were almost 1 inear with the airplane angle of attack, but scatter... is photographed in Fig. 4. Surface Pressure Instrumentation Wing surface pressures were measured using a wing glove oF Foam core construction installed over the existing inboard wing structure. The advantages to a pressure glove were that it provided I) a...

Binford, Robert Susumu

1986-01-01

4

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

5

Eclipse program QF-106 aircraft in flight  

NASA Technical Reports Server (NTRS)

This photo shows one of the QF-106s used in the Eclipse project in flight. In 1997 and 1998, the Dryden Flight Research Center at Edwards, California, supported and hosted a Kelly Space & Technology, Inc. project called Eclipse, which sought to demonstrate the feasibility of a reusable tow-launch vehicle concept. The project goal was to successfully tow, inflight, a modified QF-106 delta-wing aircraft with an Air Force C-141A transport aircraft. This would demonstrate the possibility of towing and launching an actual launch vehicle from behind a tow plane. Dryden was the responsible test organization and had flight safety responsibility for the Eclipse project. Dryden provided engineering, instrumentation, simulation, modification, maintenance, range support, and research pilots for the test program. The Air Force Flight Test Center (AFFTC), Edwards, California, supplied the C-141A transport aircraft and crew and configured the aircraft as needed for the tests. The AFFTC also provided the concept and detail design and analysis as well as hardware for the tow system and QF-106 modifications. Dryden performed the modifications to convert the QF-106 drone into the piloted EXD-01 (Eclipse eXperimental Demonstrator-01) experimental aircraft. Kelly Space & Technology hoped to use the results gleaned from the tow test in developing a series of low-cost, reusable launch vehicles. These tests demonstrated the validity of towing a delta-wing aircraft having high wing loading, validated the tow simulation model, and demonstrated various operational procedures, such as ground processing of in-flight maneuvers and emergency abort scenarios.

1997-01-01

6

Design and Development of the Aircraft Instrument Comprehension Program.  

ERIC Educational Resources Information Center

The Aircraft Instrument Comprehension (AIC) Program is a self-instructional program designed to teach undergraduate student pilots to read instruments that indicate the position of the aircraft in flight, based on sequential instructional stages of information, prompted practice, and unprompted practice. The program includes a 36-item multiple…

Higgins, Norman C.

7

Aircraft flight characteristics in icing conditions  

NASA Astrophysics Data System (ADS)

Aircraft flight dynamic characteristics can be greatly changed by ice accretion, which has been considered a considerable threat to aircraft flight safety for a long time. An overview of the studies on several ice accretion effects on aircraft flight dynamics is presented here. Special attention is paid to the following areas: ways to obtain the aerodynamic data of iced aircraft, flight dynamic modeling and simulation for iced aircraft, effects of ice accretion on aircraft stability and control as well as on flight performance and aircraft icing envelope protection and control adaption. Finally based on the progress of existing research in these areas, some key issues which deserve more attention for researchers to resolve are addressed, including obtaining aerodynamic data of iced aircraft through numerical simulation method, consummating the existing calculation models about effects of ice accretion on aircraft aerodynamic derivatives and enhancing the investigation on problems of tailplane ice accretion.

Cao, Yihua; Wu, Zhenlong; Su, Yuan; Xu, Zhongda

2015-04-01

8

Aurora Flight Sciences' Perseus B Remotely Piloted Aircraft in Flight  

NASA Technical Reports Server (NTRS)

A long, slender wing and a pusher propeller at the rear characterize the Perseus B remotely piloted research aircraft, seen here during a test flight in June 1998. Perseus B is a remotely piloted aircraft developed as a design-performance testbed under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) project. Perseus is one of several flight vehicles involved in the ERAST project. A piston engine, propeller-powered aircraft, Perseus was designed and built by Aurora Flight Sciences Corporation, Manassas, Virginia. The objectives of Perseus B's ERAST flight tests have been to reach and maintain horizontal flight above altitudes of 60,000 feet and demonstrate the capability to fly missions lasting from 8 to 24 hours, depending on payload and altitude requirements. The Perseus B aircraft established an unofficial altitude record for a single-engine, propeller-driven, remotely piloted aircraft on June 27, 1998. It reached an altitude of 60,280 feet. In 1999, several modifications were made to the Perseus aircraft including engine, avionics, and flight-control-system improvements. These improvements were evaluated in a series of operational readiness and test missions at the Dryden Flight Research Center, Edwards, California. Perseus is a high-wing monoplane with a conventional tail design. Its narrow, straight, high-aspect-ratio wing is mounted atop the fuselage. The aircraft is pusher-designed with the propeller mounted in the rear. This design allows for interchangeable scientific-instrument payloads to be placed in the forward fuselage. The design also allows for unobstructed airflow to the sensors and other devices mounted in the payload compartment. The Perseus B that underwent test and development in 1999 was the third generation of the Perseus design, which began with the Perseus Proof-Of-Concept aircraft. Perseus was initially developed as part of NASA's Small High-Altitude Science Aircraft (SHASA) program, which later evolved into the ERAST project. The Perseus Proof-Of-Concept aircraft first flew in November 1991 and made three low-altitude flights within a month to validate the Perseus aerodynamic model and flight control systems. Next came the redesigned Perseus A, which incorporated a closed-cycle combustion system that mixed oxygen carried aboard the aircraft with engine exhaust to compensate for the thin air at high altitudes. The Perseus A was towed into the air by a ground vehicle and its engine started after it became airborne. Prior to landing, the engine was stopped, the propeller locked in horizontal position, and the Perseus A glided to a landing on its unique bicycle-type landing gear. Two Perseus A aircraft were built and made 21 flights in 1993-1994. One of the Perseus A aircraft reached over 50,000 feet in altitude on its third test flight. Although one of the Perseus A aircraft was destroyed in a crash after a vertical gyroscope failed in flight, the other aircraft completed its test program and remains on display at Aurora's facility in Manassas. Perseus B first flew Oct. 7, 1994, and made two flights in 1996 before being damaged in a hard landing on the dry lakebed after a propeller shaft failure. After a number of improvements and upgrades-including extending the original 58.5-foot wingspan to 71.5 feet to enhance high-altitude performance--the Perseus B returned to Dryden in the spring of 1998 for a series of four flights. Thereafter, a series of modifications were made including external fuel pods on the wing that more than doubled the fuel capacity to 100 gallons. Engine power was increased by more than 20 percent by boosting the turbocharger output. Fuel consumption was reduced with fuel control modifications and a leaner fuel-air mixture that did not compromise power. The aircraft again crashed on Oct. 1, 1999, near Barstow, California, suffering moderate damage to the aircraft but no property damage, fire, or injuries in the area of the crash. Perseus B is flown remotely by a pilot from a mobile flight control station on the ground. A Global Positioning System (GPS) unit

1998-01-01

9

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

10

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

11

Microgravity research during aircraft parabolic flights: the 20 ESA campaigns.  

PubMed

Aircraft parabolic flights provide repeated periods of up to 20 seconds of reduced gravity during ballistic flight manoeuvres, preceded and followed by 20 seconds of 1.8 g. Such flights are used to conduct short microgravity investigations in physical and life sciences, to test instrumentation and to train astronauts before a spaceflight. Since 1984, ESA's Microgravity Projects Division has organised 20 parabolic flight campaigns using three different types of aircraft. More than 1700 parabolas have been flown, representing nine and half hours of microgravity in slices of 20 seconds, or equivalently, six low Earth orbits. A total of 235 experiments have been performed using this unique microgravity tool. PMID:14971370

Pletser, V

1995-05-01

12

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

13

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

14

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

15

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

16

Flight Controller Software Protects Lightweight Flexible Aircraft  

NASA Technical Reports Server (NTRS)

Lightweight flexible aircraft may be the future of aviation, but a major problem is their susceptibility to flutter-uncontrollable vibrations that can destroy wings. Armstrong Flight Research Center awarded SBIR funding to Minneapolis, Minnesota-based MUSYN Inc. to develop software that helps program flight controllers to suppress flutter. The technology is now available for aircraft manufacturers and other industries that use equipment with automated controls.

2015-01-01

17

Vertical flight path steering system for aircraft  

NASA Technical Reports Server (NTRS)

Disclosed is a vertical flight path angle steering system for aircraft, utilizing a digital flight control computer which processes pilot control inputs and aircraft response parameters into suitable elevator commands and control information for display to the pilot on a cathode ray tube. The system yields desirable airplane control handling qualities and responses as well as improvements in pilot workload and safety during airplane operation in the terminal area and under windshear conditions.

Lambregts, Antonius A. (Inventor)

1983-01-01

18

Measurement of In-Flight Aircraft Emissions  

NASA Technical Reports Server (NTRS)

Aircraft engine emission and their chemical and physical evolution can be measured in flight using high resolution infrared spectroscopy. The Airborne Emission Spectrometer (AES), designed for remote measure- ments of atmosphere emissions from an airborne platform, is an ideal tool for the evaluation of aircraft emissions and their evolution. Capabilities of AES will be discussed. Ground data will be given.

Sokoloski, M.; Arnold, C.; Rider, D.; Beer, R.; Worden, H.; Glavich, T.

1995-01-01

19

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

20

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

21

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

22

Eclipse program F-106 aircraft in flight, front view  

NASA Technical Reports Server (NTRS)

Shot of the QF-106 aircraft in flight with the landing gear deployed. In 1997 and 1998, the Dryden Flight Research Center at Edwards, California, supported and hosted a Kelly Space & Technology, Inc. project called Eclipse, which sought to demonstrate the feasibility of a reusable tow-launch vehicle concept. The project goal was to successfully tow, inflight, a modified QF-106 delta-wing aircraft with an Air Force C-141A transport aircraft. This would demonstrate the possibility of towing and launching an actual launch vehicle from behind a tow plane. Dryden was the responsible test organization and had flight safety responsibility for the Eclipse project. Dryden provided engineering, instrumentation, simulation, modification, maintenance, range support, and research pilots for the test program. The Air Force Flight Test Center (AFFTC), Edwards, California, supplied the C-141A transport aircraft and crew and configured the aircraft as needed for the tests. The AFFTC also provided the concept and detail design and analysis as well as hardware for the tow system and QF-106 modifications. Dryden performed the modifications to convert the QF-106 drone into the piloted EXD-01 (Eclipse eXperimental Demonstrator-01) experimental aircraft. Kelly Space & Technology hoped to use the results gleaned from the tow test in developing a series of low-cost, reusable launch vehicles. These tests demonstrated the validity of towing a delta-wing aircraft having high wing loading, validated the tow simulation model, and demonstrated various operational procedures, such as ground processing of in-flight maneuvers and emergency abort scenarios.

1997-01-01

23

Eclipse program QF-106 aircraft in flight, view from tanker  

NASA Technical Reports Server (NTRS)

View of QF-106 airplane from a KC-135 tanker aircraft. The Eclipse aircraft was not refueling but simply flying below and behind the tanker for purposes of shooting the photograph from the air. In 1997 and 1998, the Dryden Flight Research Center at Edwards, California, supported and hosted a Kelly Space & Technology, Inc. project called Eclipse, which sought to demonstrate the feasibility of a reusable tow-launch vehicle concept. The project goal was to successfully tow, inflight, a modified QF-106 delta-wing aircraft with an Air Force C-141A transport aircraft. This would demonstrate the possibility of towing and launching an actual launch vehicle from behind a tow plane. Dryden was the responsible test organization and had flight safety responsibility for the Eclipse project. Dryden provided engineering, instrumentation, simulation, modification, maintenance, range support, and research pilots for the test program. The Air Force Flight Test Center (AFFTC), Edwards, California, supplied the C-141A transport aircraft and crew and configured the aircraft as needed for the tests. The AFFTC also provided the concept and detail design and analysis as well as hardware for the tow system and QF-106 modifications. Dryden performed the modifications to convert the QF-106 drone into the piloted EXD-01 (Eclipse eXperimental Demonstrator -01) experimental aircraft. Kelly Space & Technology hoped to use the results gleaned from the tow test in developing a series of low-cost, reusable launch vehicles. These tests demonstrated the validity of towing a delta-wing aircraft having high wing loading, validated the tow simulation model, and demonstrated various operational procedures, such as ground processing of in-flight maneuvers and emergency abort scenarios.

1997-01-01

24

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

25

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

26

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

27

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

28

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

29

Schlieren Imaging Of An Aircraft In Flight  

NASA Technical Reports Server (NTRS)

Technique for making schlieren images of airplanes and missiles in supersonic flight devised to help understand physics of compressible aerodynamic flows about complicated aircraft shapes. Technique also used to study far-field sonic booms. Data obtained from schlieren images useful in optimizing designs of prototype aircraft. Technique incorporates elements of focusing schlieren photography, astronomical photography, and streak photography. Using sun or moon as source of light, apparatus forms image revealing gradients of density in air flow.

Weinstein, Leonard M.

1994-01-01

30

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

Code of Federal Regulations, 2012 CFR

...Initial and transition training and checking: Flight instructors (aircraft), flight instructors (simulator). 91.1095 Section...GENERAL OPERATING RULES GENERAL OPERATING AND FLIGHT RULES Fractional Ownership Operations...

2012-01-01

31

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

Code of Federal Regulations, 2014 CFR

...Initial and transition training and checking: Flight instructors (aircraft), flight instructors (simulator). 91.1095 Section...GENERAL OPERATING RULES GENERAL OPERATING AND FLIGHT RULES Fractional Ownership Operations...

2014-01-01

32

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

Code of Federal Regulations, 2013 CFR

...Initial and transition training and checking: Flight instructors (aircraft), flight instructors (simulator). 91.1095 Section...GENERAL OPERATING RULES GENERAL OPERATING AND FLIGHT RULES Fractional Ownership Operations...

2013-01-01

33

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

34

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

35

Pathfinder aircraft returning from a flight  

NASA Technical Reports Server (NTRS)

The Pathfinder solar-powered research aircraft settles in for landing on the bed of Rogers Dry Lake at the Dryden Flight Research Center, Edwards, California, after a successful test flight Nov. 19, 1996. The ultra-light craft flew a racetrack pattern at low altitudes over the flight test area for two hours while project engineers checked out various systems and sensors on the uninhabited aircraft. The Pathfinder was controlled by two pilots, one in a mobile control unit which followed the craft, the other in a stationary control station. Pathfinder, developed by AeroVironment, Inc., is one of several designs 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. (See the Pathfinder Plus photos and project description.)

1996-01-01

36

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

37

Aircraft digital flight control technical review  

NASA Technical Reports Server (NTRS)

The Aircraft Digital Flight Control Technical Review was initiated by two pilot induced oscillation (PIO) incidents in the spring and summer of 1992. Maj. Gen. Franklin (PEO) wondered why the Air Force development process for digital flight control systems was not preventing PIO problems. Consequently, a technical review team was formed to examine the development process and determine why PIO problems continued to occur. The team was also to identify the 'best practices' used in the various programs. The charter of the team was to focus on the PIO problem, assess the current development process, and document the 'best practices.' The team reviewed all major USAF aircraft programs with digital flight controls, specifically, the F-15E, F-16C/D, F-22, F-111, C-17, and B-2. The team interviewed contractor, System Program Office (SPO), and Combined Test Force (CTF) personnel on these programs. The team also went to NAS Patuxent River to interview USN personnel about the F/A-18 program. The team also reviewed experimental USAF and NASA systems with digital flight control systems: X-29, X-31, F-15 STOL and Maneuver Technology Demonstrator (SMTD), and the Variable In-Flight Stability Test Aircraft (VISTA). The team also discussed the problem with other experts in the field including Ralph Smith and personnel from Calspan. The major conclusions and recommendations from the review are presented.

Davenport, Otha B.; Leggett, David B.

1993-01-01

38

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

39

B-52 Launch Aircraft in Flight  

NASA Technical Reports Server (NTRS)

NASA's venerable B-52 mothership is seen here photographed from a KC-135 Tanker aircraft. The X-43 adapter is visible attached to the right wing. The B-52, used for launching experimental aircraft and for other flight research projects, has been a familiar sight in the skies over Edwards for more than 40 years and is also both the oldest B-52 still flying and the aircraft with the lowest flight time of any B-52. NASA B-52, Tail Number 008, is an air launch carrier aircraft, 'mothership,' as well as a research aircraft platform that has been used on a variety of research projects. The aircraft, a 'B' model built in 1952 and first flown on June 11, 1955, is the oldest B-52 in flying status and has been used on some of the most significant research projects in aerospace history. Some of the significant projects supported by B-52 008 include the X-15, the lifting bodies, HiMAT (highly maneuverable aircraft technology), Pegasus, validation of parachute systems developed for the space shuttle program (solid-rocket-booster recovery system and the orbiter drag chute system), and the X-38. The B-52 served as the launch vehicle on 106 X-15 flights and flew a total of 159 captive-carry and launch missions in support of that program from June 1959 to October 1968. Information gained from the highly successful X-15 program contributed to the Mercury, Gemini, and Apollo human spaceflight programs as well as space shuttle development. Between 1966 and 1975, the B-52 served as the launch aircraft for 127 of the 144 wingless lifting body flights. In the 1970s and 1980s, the B-52 was the launch aircraft for several aircraft at what is now the Dryden Flight Research Center, Edwards, California, to study spin-stall, high-angle-of attack, and maneuvering characteristics. These included the 3/8-scale F-15/spin research vehicle (SRV), the HiMAT (Highly Maneuverable Aircraft Technology) research vehicle, and the DAST (drones for aerodynamic and structural testing). The aircraft supported the development of parachute recovery systems used to recover the space shuttle solid rocket booster casings. It also supported eight orbiter (space shuttle) drag chute tests in 1990. In addition, the B-52 served as the air launch platform for the first six Pegasus space boosters. During its many years of service, the B-52 has undergone several modifications. The first major modification was made by North American Aviation (now part of Boeing) in support of the X-15 program. This involved creating a launch-panel-operator station for monitoring the status of the test vehicle being carried, cutting a large notch in the right inboard wing flap to accommodate the vertical tail of the X-15 aircraft, and installing a wing pylon that enables the B-52 to carry research vehicles and test articles to be air-launched/dropped. Located on the right wing, between the inboard engine pylon and the fuselage, this wing pylon was subjected to extensive testing prior to its use. For each test vehicle the B-52 carried, minor changes were made to the launch-panel operator's station. Built originally by the Boeing Company, the NASA B-52 is powered by eight Pratt & Whitney J57-19 turbojet engines, each of which produce 12,000 pounds of thrust. The aircraft's normal launch speed has been Mach 0.8 (about 530 miles per hour) and its normal drop altitude has been 40,000 to 45,000 feet. It is 156 feet long and has a wing span of 185 feet.

2001-01-01

40

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

41

The Communicative Relevancies of Instrument Flight; A Technologically Contingent World.  

ERIC Educational Resources Information Center

The success and safety of flight in actual instrument conditions is dependent upon the communicative competency of the individuals involved. The more obvious elements of communication involved include crew coordination and communication both verbal and nonverbal, aircraft and ground communication links, pilot interpretation of verbally and…

McCoy, Claire Elaine

42

NASA Shuttle Training Aircraft flight simulation overview  

NASA Technical Reports Server (NTRS)

The Shuttle Training Aircraft (STA) is a variable stability, variable control law flying simulator used by NASA/JSC to train astronauts in the final landing phase of a Space Shuttle Orbiter. A general outline is given for the STA flight simulation system. An overview is given of the software generation and verification process through the Advanced Validation System (AVAS). The flight test techniques for software verification will be reviewed and the process for releasing the software for flight training will be covered. The astronaut STA training syllabus is examined. Parameter matching with the Orbiter in the final approach phase of de-orbit and landing is briefly examined. Simulation performance will be assessed against flight data, performance measurement, and cue synchronization.

Justiz, Charles R.; Patel, Suresh M.

1988-01-01

43

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

44

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

45

Practice and Incentive Effects on Learner Performance: Aircraft Instrument Comprehension Task.  

ERIC Educational Resources Information Center

To study the effects of practice and incentive on learner performance on the aircraft instrument comprehension task, 48 third-year Air Force cadets were chosen as subjects. The subjects were expected to be able to identify which one of four pictures of aircraft in flight most nearly corresponded to the position indicated on a panel of attitude and…

Tenpas, Barbara G.; Higgins, Norman C.

46

14 CFR 91.1091 - Qualifications: Flight instructors (aircraft) and flight instructors (simulator).  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Qualifications: Flight instructors (aircraft) and flight instructors (simulator). 91.1091 Section...GENERAL OPERATING RULES GENERAL OPERATING AND FLIGHT RULES Fractional Ownership Operations...

2010-01-01

47

14 CFR 91.1091 - Qualifications: Flight instructors (aircraft) and flight instructors (simulator).  

Code of Federal Regulations, 2013 CFR

...2013-01-01 2013-01-01 false Qualifications: Flight instructors (aircraft) and flight instructors (simulator). 91.1091 Section...GENERAL OPERATING RULES GENERAL OPERATING AND FLIGHT RULES Fractional Ownership Operations...

2013-01-01

48

14 CFR 91.1091 - Qualifications: Flight instructors (aircraft) and flight instructors (simulator).  

Code of Federal Regulations, 2011 CFR

...2011-01-01 2011-01-01 false Qualifications: Flight instructors (aircraft) and flight instructors (simulator). 91.1091 Section...GENERAL OPERATING RULES GENERAL OPERATING AND FLIGHT RULES Fractional Ownership Operations...

2011-01-01

49

14 CFR 91.1091 - Qualifications: Flight instructors (aircraft) and flight instructors (simulator).  

Code of Federal Regulations, 2012 CFR

...2012-01-01 2012-01-01 false Qualifications: Flight instructors (aircraft) and flight instructors (simulator). 91.1091 Section...GENERAL OPERATING RULES GENERAL OPERATING AND FLIGHT RULES Fractional Ownership Operations...

2012-01-01

50

14 CFR 91.1091 - Qualifications: Flight instructors (aircraft) and flight instructors (simulator).  

Code of Federal Regulations, 2014 CFR

...2014-01-01 2014-01-01 false Qualifications: Flight instructors (aircraft) and flight instructors (simulator). 91.1091 Section...GENERAL OPERATING RULES GENERAL OPERATING AND FLIGHT RULES Fractional Ownership Operations...

2014-01-01

51

Optimum flight paths of turbojet aircraft  

NASA Technical Reports Server (NTRS)

The climb of turbojet aircraft is analyzed and discussed including the accelerations. Three particular flight performances are examined: minimum time of climb, climb with minimum fuel consumption, and steepest climb. The theoretical results obtained from a previous study are put in a form that is suitable for application on the following simplifying assumptions: the Mach number is considered an independent variable instead of the velocity; the variations of the airplane mass due to fuel consumption are disregarded; the airplane polar is assumed to be parabolic; the path curvatures and the squares of the path angles are disregarded in the projection of the equation of motion on the normal to the path; lastly, an ideal turbojet with performance independent of the velocity is involved. The optimum Mach number for each flight condition is obtained from the solution of a sixth order equation in which the coefficients are functions of two fundamental parameters: the ratio of minimum drag in level flight to the thrust and the Mach number which represents the flight at constant altitude and maximum lift-drag ratio.

Miele, Angelo

1955-01-01

52

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

53

Two YF-12 aircraft in flight  

NASA Technical Reports Server (NTRS)

The YF-12A (60-6935) carries the 'coldwall' heat transfer pod on a pylon beneath the forward fuselage. The pod is seen with its insulating coating intact. In the foreground, the YF-12C flies photo chase. The coldwall project, supported by Langley Research Center, consisted of a stainless steel tube equipped with thermocouples and pressure-sensors. A special insulating coating covered the tube, which was chilled with liquid nitrogen. At Mach 3, the insulation could be pyrotechnically blown away from the tube, instantly exposing it to the thermal environment. The experiment caused many inflight difficulties, such as engine unstarts, but eventually researchers got a successful flight. The Flight Research Center's involvement with the YF-12A, an interceptor version of the Lockheed A-12, began in 1967. Ames Research Center was interested in using wind tunnel data that had been generated at Ames under extreme secrecy. Also, the Office of Advanced Research and Technology (OART) saw the YF-12A as a means to advance high-speed technology, which would help in designing the Supersonic Transport (SST). The Air Force needed technical assistance to get the latest reconnaissance version of the A-12 family, the SR-71A, fully operational. Eventually, the Air Force offered NASA the use of two YF-12A aircraft, 60-6935 and 60-6936. A joint NASA-USAF program was mapped out in June 1969. NASA and Air Force technicians spent three months readying 935 for flight. On 11 December 1969, the flight program got underway with a successful maiden flight piloted by Col. Joe Rogers and Maj. Gary Heidelbaugh of the SR-71/F-12 Test Force. During the program, the Air Force concentrated on military applications, and NASA pursued a loads research program. NASA studies included inflight heating, skin-friction cooling, 'coldwall' research (a heat transfer experiment), flowfield studies, shaker vane research, and tests in support of the Space Shuttle landing program. Ultimately, 935 became the workhorse of the program, with 146 flights between 11 December 1969 and 7 November 1979. The second YF-12A, 936, made 62 flights. It was lost in a non-fatal crash on 24 June 1971. It was replaced by the so-called YF-12C (SR-71A 61-7951, modified with YF-12A inlets and engines and a bogus tail number 06937). The Lockheed A-12 family, known as the Blackbirds, were designed by Clarence 'Kelly' Johnson. They were constructed mostly of titanium to withstand aerodynamic heating. Fueled by JP-7, the Blackbirds were capable of cruising at Mach 3.2 and attaining altitudes in excess of 80,000 feet. The first version, a CIA reconnaissance aircraft that first flew in April 1962 was called the A-12. An interceptor version was developed in 1963 under the designation YF-12A. A USAF reconnaissance variant, called the SR-71, was first flown in 1964. The A-12 and SR-71 designs included leading and trailing edges made of high-temperature fiberglass-asbestos laminates. The NASA YF-12 research program was ambitious; the aircraft flew an average of once a week unless down for extended maintenance or modification. Program expenses averaged $3.1 million per year just to run the flight tests. NASA crews for the YF-12 included pilots Fitzhugh Fulton and Donald Mallick, anf flight test engineers Victor Horton and Ray Young. Other NASA test pilots checked out in the YF-12A included John Manke, William Dana, Gary Krier, Einar Enevoldson, Tom McMurtry, Steve Ishmael, and Michael Swann. The YF-12C was only flown by Fulton, Mallick, Horton, and Ray.

1975-01-01

54

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

Code of Federal Regulations, 2014 CFR

...2014-01-01 2014-01-01 false Special flight authorizations for foreign civil aircraft...OPERATING RULES GENERAL OPERATING AND FLIGHT RULES Foreign Aircraft Operations...Board Such Aircraft § 91.715 Special flight authorizations for foreign civil...

2014-01-01

55

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

Code of Federal Regulations, 2012 CFR

...2012-01-01 2012-01-01 false Special flight authorizations for foreign civil aircraft...OPERATING RULES GENERAL OPERATING AND FLIGHT RULES Foreign Aircraft Operations...Board Such Aircraft § 91.715 Special flight authorizations for foreign civil...

2012-01-01

56

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

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Special flight authorizations for foreign civil aircraft...OPERATING RULES GENERAL OPERATING AND FLIGHT RULES Foreign Aircraft Operations...Board Such Aircraft § 91.715 Special flight authorizations for foreign civil...

2010-01-01

57

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

58

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

59

Flight test techniques for validating simulated nuclear electromagnetic pulse aircraft responses  

NASA Technical Reports Server (NTRS)

An attempt has been made to determine the effects of nuclear EM pulses (NEMPs) on aircraft systems, using a highly instrumented NASA F-106B to document the simulated NEMP environment at the Kirtland Air Force Base's Vertically Polarized Dipole test facility. Several test positions were selected so that aircraft orientation relative to the test facility would be the same in flight as when on the stationary dielectric stand, in order to validate the dielectric stand's use in flight configuration simulations. Attention is given to the flight test portions of the documentation program.

Winebarger, R. M.; Neely, W. R., Jr.

1984-01-01

60

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

61

State estimation applications in aircraft flight-data analysis: A user's manual for SMACK  

NASA Technical Reports Server (NTRS)

The evolution in the use of state estimation is traced for the analysis of aircraft flight data. A unifying mathematical framework for state estimation is reviewed, and several examples are presented that illustrate a general approach for checking instrument accuracy and data consistency, and for estimating variables that are difficult to measure. Recent applications associated with research aircraft flight tests and airline turbulence upsets are described. A computer program for aircraft state estimation is discussed in some detail. This document is intended to serve as a user's manual for the program called SMACK (SMoothing for AirCraft Kinematics). The diversity of the applications described emphasizes the potential advantages in using SMACK for flight-data analysis.

Bach, Ralph E., Jr.

1991-01-01

62

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

NASA Technical Reports Server (NTRS)

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

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

1985-01-01

63

Analysis of instrumentation error effects on the identification accuracy of aircraft parameters  

NASA Technical Reports Server (NTRS)

An analytical investigation is presented of the effect of unmodeled measurement system errors on the accuracy of aircraft stability and control derivatives identified from flight test data. Such error sources include biases, scale factor errors, instrument position errors, misalignments, and instrument dynamics. Two techniques (ensemble analysis and simulated data analysis) are formulated to determine the quantitative variations to the identified parameters resulting from the unmodeled instrumentation errors. The parameter accuracy that would result from flight tests of the F-4C aircraft with typical quality instrumentation is determined using these techniques. It is shown that unmodeled instrument errors can greatly increase the uncertainty in the value of the identified parameters. General recommendations are made of procedures to be followed to insure that the measurement system associated with identifying stability and control derivatives from flight test provides sufficient accuracy.

Sorensen, J. A.

1972-01-01

64

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

65

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

66

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

67

Subscale Flight Testing for Aircraft Loss of Control: Accomplishments and Future Directions  

NASA Technical Reports Server (NTRS)

Subscale flight-testing provides a means to validate both dynamic models and mitigation technologies in the high-risk flight conditions associated with aircraft loss of control. The Airborne Subscale Transport Aircraft Research (AirSTAR) facility was designed to be a flexible and efficient research facility to address this type of flight-testing. Over the last several years (2009-2011) it has been used to perform 58 research flights with an unmanned, remotely-piloted, dynamically-scaled airplane. This paper will present an overview of the facility and its architecture and summarize the experimental data collected. All flights to date have been conducted within visual range of a safety observer. Current plans for the facility include expanding the test volume to altitudes and distances well beyond visual range. The architecture and instrumentation changes associated with this upgrade will also be presented.

Cox, David E.; Cunningham, Kevin; Jordan, Thomas L.

2012-01-01

68

Flight instrumentation specification for parameter identification: Program user's guide. [instrument errors/error analysis  

NASA Technical Reports Server (NTRS)

A set of four digital computer programs is presented which can be used to investigate the effects of instrumentation errors on the accuracy of aircraft and helicopter stability-and-control derivatives identified from flight test data. The programs assume that the differential equations of motion are linear and consist of small perturbations about a quasi-steady flight condition. It is also assumed that a Newton-Raphson optimization technique is used for identifying the estimates of the parameters. Flow charts and printouts are included.

Mohr, R. L.

1975-01-01

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

14 CFR 91.9 - Civil aircraft flight manual, marking, and placard requirements.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Civil aircraft flight manual, marking, and placard requirements...GENERAL OPERATING RULES GENERAL OPERATING AND FLIGHT RULES General § 91.9 Civil aircraft flight manual, marking, and placard...

2013-01-01

71

14 CFR 91.9 - Civil aircraft flight manual, marking, and placard requirements.  

Code of Federal Regulations, 2014 CFR

... 2014-01-01 false Civil aircraft flight manual, marking, and placard requirements...GENERAL OPERATING RULES GENERAL OPERATING AND FLIGHT RULES General § 91.9 Civil aircraft flight manual, marking, and placard...

2014-01-01

72

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

73

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

74

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

75

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

76

Flight Testing the Rotor Systems Research Aircraft (RSRA)  

NASA Technical Reports Server (NTRS)

In the late 1960s, efforts to advance the state-of-the-art in rotor systems technology indicated a significant gap existed between our ability to accurately predict the characteristics of a complex rotor system and the results obtained through flight verification. Even full scale wind tunnel efforts proved inaccurate because of the complex nature of a rotating, maneuvering rotor system. The key element missing, which prevented significant advances, was our inability to precisely measure the exact rotor state as a function of time and flight condition. Two Rotor Research Aircraft (RSRA) were designed as pure research aircraft and dedicated rotor test vehicles whose function is to fill the gap between theory, wind tunnel testing, and flight verification. The two aircraft, the development of the piloting techniques required to safely fly the compound helicopter, the government flight testing accomplished to date, and proposed future research programs.

Hall, G. W.; Merrill, R. K.

1983-01-01

77

Ground and Flight Evaluation of a Small-Scale Inflatable-Winged Aircraft  

NASA Technical Reports Server (NTRS)

A small-scale, instrumented research aircraft was flown to investigate the night characteristics of innersole wings. Ground tests measured the static structural characteristics of the wing at different inflation pressures, and these results compared favorably with analytical predictions. A research-quality instrumentation system was assembled, largely from commercial off-the-shelf components, and installed in the aircraft. Initial flight operations were conducted with a conventional rigid wing having the same dimensions as the inflatable wing. Subsequent flights were conducted with the inflatable wing. Research maneuvers were executed to identify the trim, aerodynamic performance, and longitudinal stability and control characteristics of the vehicle in its different wing configurations. For the angle-of-attack range spanned in this flight program, measured flight data demonstrated that the rigid wing was an effective simulator of the lift-generating capability of the inflatable wing. In-flight inflation of the wing was demonstrated in three flight operations, and measured flight data illustrated the dynamic characteristics during wing inflation and transition to controlled lifting flight. Wing inflation was rapid and the vehicle dynamics during inflation and transition were benign. The resulting angles of attack and of sideslip ere small, and the dynamic response was limited to roll and heave motions.

Murray, James E.; Pahle, Joseph W.; Thornton, Stephen V.; Vogus, Shannon; Frackowiak, Tony; Mello, Joe; Norton, Brook; Bauer, Jeff (Technical Monitor)

2002-01-01

78

A Preliminary Flight Investigation of Formation Flight for Drag Reduction on the C-17 Aircraft  

NASA Technical Reports Server (NTRS)

Many theoretical and experimental studies have shown that aircraft flying in formation could experience significant reductions in fuel use compared to solo flight. To date, formation flight for aerodynamic benefit has not been thoroughly explored in flight for large transport-class vehicles. This paper summarizes flight data gathered during several two ship, C-17 formation flights at a single flight condition of 275 knots, at 25,000 ft MSL. Stabilized test points were flown with the trail aircraft at 1,000 and 3,000 ft aft of the lead aircraft at selected crosstrack and vertical offset locations within the estimated area of influence of the vortex generated by the lead aircraft. Flight data recorded at test points within the vortex from the lead aircraft are compared to data recorded at tare flight test points outside of the influence of the vortex. Since drag was not measured directly, reductions in fuel flow and thrust for level flight are used as a proxy for drag reduction. Estimated thrust and measured fuel flow reductions were documented at several trail test point locations within the area of influence of the leads vortex. The maximum average fuel flow reduction was approximately 7-8%, compared to the tare points flown before and after the test points. Although incomplete, the data suggests that regions with fuel flow and thrust reduction greater than 10% compared to the tare test points exist within the vortex area of influence.

Pahle, Joe; Berger, Dave; Venti, Michael W.; Faber, James J.; Duggan, Chris; Cardinal, Kyle

2012-01-01

79

Flight Testing and Test Instrumentation of PHOENIX  

NASA Astrophysics Data System (ADS)

Within the frame of the German national ASTRA program, the need for in-flight experimentation as a key element in the development of the next generation launcher was addressed by the Phoenix project. The Phoenix 1 flight test vehicle was designed to demonstrate the un-powered horizontal landing of a representative, winged RLV configuration. The Phoenix 1 flight test vehicle is downscaled from the reference RLV shape "Hopper", with the dimensions of 7.8m overall length, 3.8m span, and 1200kg mass. In order to be representative of a full scale RLV, the scaling method preserves all features challenging the automatic landing from the flight control point of view. These are in particular the poor flying qualities of the static unstable vehicle and the high landing velocity of 71m/s, which is same as for the full scale vehicle. The landing demonstration scenario comprises a drop from the helicopter approximately 6km ahead of the runway threshold at 2.4km above runway level. The subsequent free flight includes an accelerating dive to merge with a steep final approach path representative of an RLV, followed by a long flare, touch down on the runway, and rollout to standstill. Besides its mandatory avionics system, the vehicle is also equipped with an additional flight test instrumentation to identify local aerodynamic flow and structural stress. This FTI system is designed to collect data by recording about 130 sensor signals during flight. This test instrumentation system was operated during a test campaign dedicated to verify the aerodynamic data base of Phoenix in the Dutch-German Wind-tunnel (DNW) in August 2003 and during three automatic landing flight tests after helicopter drop in May 2004. Post flight analysis of these data allows to validate the design models and the development tools in order to establish a flight validated data base for future work. This paper gives an overview on the Phoenix system including the flight test instrumentation, the test program and the results and lessons learned from the different campaigns.

Janovsky, R.; Behr, R.

2005-02-01

80

14 CFR 25.1303 - Flight and navigation instruments.  

Code of Federal Regulations, 2010 CFR

...presentation. (3) A direction indicator (nonstabilized magnetic compass). (b) The following flight and navigation instruments...A direction indicator (gyroscopically stabilized, magnetic or nonmagnetic). (c) The following flight...

2010-01-01

81

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

82

X-36 Tailless Fighter Agility Research Aircraft in flight  

NASA Technical Reports Server (NTRS)

The lack of a vertical tail on the X-36 technology demonstrator is evident as the remotely piloted aircraft flies a low-altitude research flight above Rogers Dry Lake at Edwards Air Force Base in the California desert on October 30, 1997. The NASA/Boeing X-36 Tailless Fighter Agility Research Aircraft program successfully demonstrated the tailless fighter design using advanced technologies to improve the maneuverability and survivability of possible future fighter aircraft. The program met or exceeded all project goals. For 31 flights during 1997 at the Dryden Flight Research Center, Edwards, California, the project team examined the aircraft's agility at low speed / high angles of attack and at high speed / low angles of attack. The aircraft's speed envelope reached up to 206 knots (234 mph). This aircraft was very stable and maneuverable. It handled very well. The X-36 vehicle was designed to fly without the traditional tail surfaces common on most aircraft. Instead, a canard forward of the wing was used as well as split ailerons and an advanced thrust-vectoring nozzle for directional control. The X-36 was unstable in both pitch and yaw axes, so an advanced, single-channel digital fly-by-wire control system (developed with some commercially available components) was put in place to stabilize the aircraft. Using a video camera mounted in the nose of the aircraft and an onboard microphone, the X-36 was remotely controlled by a pilot in a ground station virtual cockpit. A standard fighter-type head-up display (HUD) and a moving-map representation of the vehicle's position within the range in which it flew provided excellent situational awareness for the pilot. This pilot-in-the-loop approach eliminated the need for expensive and complex autonomous flight control systems and the risks associated with their inability to deal with unknown or unforeseen phenomena in flight. Fully fueled the X-36 prototype weighed approximately 1,250 pounds. It was 19 feet long and three feet high with a wingspan of just over 10 feet. A Williams International F112 turbofan engine provided close to 700 pounds of thrust. A typical research flight lasted 35 to 45 minutes from takeoff to touchdown. A total of 31 successful research flights were flown from May 17, 1997, to November 12, 1997, amassing 15 hours and 38 minutes of flight time. The aircraft reached an altitude of 20,200 feet and a maximum angle of attack of 40 degrees. In a follow-on effort, the Air Force Research Laboratory (AFRL), Wright-Patterson Air Force Base, Ohio, contracted with Boeing to fly AFRL's Reconfigurable Control for Tailless Fighter Aircraft (RESTORE) software as a demonstration of the adaptability of the neural-net algorithm to compensate for in-flight damage or malfunction of effectors, such as flaps, ailerons and rudders. Two RESTORE research flights were flown in December 1998, proving the viability of the software approach. The X-36 aircraft flown at the Dryden Flight Research Center in 1997 was a 28-percent scale representation of a theoretical advanced fighter aircraft. The Boeing Phantom Works (formerly McDonnell Douglas) in St. Louis, Missouri, built two of the vehicles in a cooperative agreement with the Ames Research Center, Moffett Field, California.

1997-01-01

83

X-36 Tailless Fighter Agility Research Aircraft in flight  

NASA Technical Reports Server (NTRS)

The tailless X-36 technology demonstrator research aircraft cruises over the California desert at low altitude during a 1997 research flight. The NASA/Boeing X-36 Tailless Fighter Agility Research Aircraft program successfully demonstrated the tailless fighter design using advanced technologies to improve the maneuverability and survivability of possible future fighter aircraft. The program met or exceeded all project goals. For 31 flights during 1997 at the Dryden Flight Research Center, Edwards, California, the project team examined the aircraft's agility at low speed / high angles of attack and at high speed / low angles of attack. The aircraft's speed envelope reached up to 206 knots (234 mph). This aircraft was very stable and maneuverable. It handled very well. The X-36 vehicle was designed to fly without the traditional tail surfaces common on most aircraft. Instead, a canard forward of the wing was used as well as split ailerons and an advanced thrust-vectoring nozzle for directional control. The X-36 was unstable in both pitch and yaw axes, so an advanced, single-channel digital fly-by-wire control system (developed with some commercially available components) was put in place to stabilize the aircraft. Using a video camera mounted in the nose of the aircraft and an onboard microphone, the X-36 was remotely controlled by a pilot in a ground station virtual cockpit. A standard fighter-type head-up display (HUD) and a moving-map representation of the vehicle's position within the range in which it flew provided excellent situational awareness for the pilot. This pilot-in-the-loop approach eliminated the need for expensive and complex autonomous flight control systems and the risks associated with their inability to deal with unknown or unforeseen phenomena in flight. Fully fueled the X-36 prototype weighed approximately 1,250 pounds. It was 19 feet long and three feet high with a wingspan of just over 10 feet. A Williams International F112 turbofan engine provided close to 700 pounds of thrust. A typical research flight lasted 35 to 45 minutes from takeoff to touchdown. A total of 31 successful research flights were flown from May 17, 1997, to November 12, 1997, amassing 15 hours and 38 minutes of flight time. The aircraft reached an altitude of 20,200 feet and a maximum angle of attack of 40 degrees. In a follow-on effort, the Air Force Research Laboratory (AFRL), Wright-Patterson Air Force Base, Ohio, contracted with Boeing to fly AFRL's Reconfigurable Control for Tailless Fighter Aircraft (RESTORE) software as a demonstration of the adaptability of the neural-net algorithm to compensate for in-flight damage or malfunction of effectors, such as flaps, ailerons and rudders. Two RESTORE research flights were flown in December 1998, proving the viability of the software approach. The X-36 aircraft flown at the Dryden Flight Research Center in 1997 was a 28-percent scale representation of a theoretical advanced fighter aircraft. The Boeing Phantom Works (formerly McDonnell Douglas) in St. Louis, Missouri, built two of the vehicles in a cooperative agreement with the Ames Research Center, Moffett Field, California.

1997-01-01

84

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

85

Instrumentation of sampling aircraft for measurement of launch vehicle effluents  

NASA Technical Reports Server (NTRS)

An aircraft was selected and instrumented to measure effluents emitted from large solid propellant rockets during launch activities. The considerations involved in aircraft selection, sampling probes, and instrumentation are discussed with respect to obtaining valid airborne measurements. Discussions of the data acquisition system used, the instrument power system, and operational sampling procedures are included. Representative measurements obtained from an actual rocket launch monitoring activity are also presented.

Wornom, D. E.; Woods, D. C.; Thomas, M. E.; Tyson, R. W.

1977-01-01

86

Flight evaluation of pursuit displays for precision approach of powered-lift aircraft  

NASA Technical Reports Server (NTRS)

Flight experiments with NASA Ames Research Center's quiet short-haul research aircraft evaluated the influence of pursuit displays on the ability of pilots to execute precision-instrument flight operations in the terminal area, particularly approaches to and landings on a short runway. The aircraft is a powered-lift, short-takeoff and landing configuration equipped with a modern digital fly-by-wire flight control system, a head-up display, and a color head-down display that make it possible to investigate control and display concepts for full-envelope, powered-lift operations. Flight-path-oriented displays that provide status and command information in a format with minimal clutter were investigated. The pilots could fly the aircraft with the precision associated with flight-director guidance and with a high degree of situation awareness. The primary benefits of this display concept were realized when the pilot was required to execute a complex transition and approach under instrument conditions and in the presence of a wide range of wind and turbulence conditions.

Hynes, Charles S.; Franklin, James A.; Hardy, Gordon H.; Martin, James L.; Innis, Robert C.

1989-01-01

87

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

88

Automatic flight envelope protection for light general aviation aircraft  

Microsoft Academic Search

Aircraft loss-of-control accidents account for about 38% of the fatal accidents in U.S. General Aviation operations each year. Loss-of-control accidents include VFR-into-IMC with subsequent disorientation and loss of aircraft control, low-speed stall-spin accidents in the airport traffic pattern, and high-speed accelerated stall accidents during low-level maneuvering. The majority of these accidents could be prevented by full-time flight envelope protection having

John M. Wilson; Mark E. Peters

2009-01-01

89

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

90

X-36 Tailless Fighter Agility Research Aircraft in flight  

NASA Technical Reports Server (NTRS)

The X-36 technology demonstrator shows off its distinctive shape as the remotely piloted aircraft flies a research mission over the Southern California desert on October 30, 1997. The NASA/Boeing X-36 Tailless Fighter Agility Research Aircraft program successfully demonstrated the tailless fighter design using advanced technologies to improve the maneuverability and survivability of possible future fighter aircraft. The program met or exceeded all project goals. For 31 flights during 1997 at the Dryden Flight Research Center, Edwards, California, the project team examined the aircraft's agility at low speed / high angles of attack and at high speed / low angles of attack. The aircraft's speed envelope reached up to 206 knots (234 mph). This aircraft was very stable and maneuverable. It handled very well. The X-36 vehicle was designed to fly without the traditional tail surfaces common on most aircraft. Instead, a canard forward of the wing was used as well as split ailerons and an advanced thrust-vectoring nozzle for directional control. The X-36 was unstable in both pitch and yaw axes, so an advanced, single-channel digital fly-by-wire control system (developed with some commercially available components) was put in place to stabilize the aircraft. Using a video camera mounted in the nose of the aircraft and an onboard microphone, the X-36 was remotely controlled by a pilot in a ground station virtual cockpit. A standard fighter-type head-up display (HUD) and a moving-map representation of the vehicle's position within the range in which it flew provided excellent situational awareness for the pilot. This pilot-in-the-loop approach eliminated the need for expensive and complex autonomous flight control systems and the risks associated with their inability to deal with unknown or unforeseen phenomena in flight. Fully fueled the X-36 prototype weighed approximately 1,250 pounds. It was 19 feet long and three feet high with a wingspan of just over 10 feet. A Williams International F112 turbofan engine provided close to 700 pounds of thrust. A typical research flight lasted 35 to 45 minutes from takeoff to touchdown. A total of 31 successful research flights were flown from May 17, 1997, to November 12, 1997, amassing 15 hours and 38 minutes of flight time. The aircraft reached an altitude of 20,200 feet and a maximum angle of attack of 40 degrees. In a follow-on effort, the Air Force Research Laboratory (AFRL), Wright-Patterson Air Force Base, Ohio, contracted with Boeing to fly AFRL's Reconfigurable Control for Tailless Fighter Aircraft (RESTORE) software as a demonstration of the adaptability of the neural-net algorithm to compensate for in-flight damage or malfunction of effectors, such as flaps, ailerons and rudders. Two RESTORE research flights were flown in December 1998, proving the viability of the software approach. The X-36 aircraft flown at the Dryden Flight Research Center in 1997 was a 28-percent scale representation of a theoretical advanced fighter aircraft. The Boeing Phantom Works (formerly McDonnell Douglas) in St. Louis, Missouri, built two of the vehicles in a cooperative agreement with the Ames Research Center, Moffett Field, California.

1997-01-01

91

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

92

Estimation of aircraft aerodynamic parameters from flight data  

NASA Technical Reports Server (NTRS)

Several ways for obtaining aerodynamic parameters of an aircraft from flight data are presented. A brief description of data analysis from steady measurements is given, and a concept of system identification is introduced. This is followed by a mathematical model of an aircraft with aerodynamic forces and moments approximated either by polynomials or splines and a detailed treatment of two often-used techniques for parameter estimation. Because of renewed interest in frequency-domain analysis, one section of the paper is devoted to this problem. The methods are demonstrated in several examples using real flight data.

Klein, Vladislav

1989-01-01

93

Optimizing aircraft performance with adaptive, integrated flight/propulsion control  

NASA Technical Reports Server (NTRS)

The Performance-Seeking Control (PSC) integrated flight/propulsion adaptive control algorithm presented was developed in order to optimize total aircraft performance during steady-state engine operation. The PSC multimode algorithm minimizes fuel consumption at cruise conditions, while maximizing excess thrust during aircraft accelerations, climbs, and dashes, and simultaneously extending engine service life through reduction of fan-driving turbine inlet temperature upon engagement of the extended-life mode. The engine models incorporated by the PSC are continually upgraded, using a Kalman filter to detect anomalous operations. The PSC algorithm will be flight-demonstrated by an F-15 at NASA-Dryden.

Smith, R. H.; Chisholm, J. D.; Stewart, J. F.

1991-01-01

94

Theory of Aircraft Flight. Aerospace Education II.  

ERIC Educational Resources Information Center

This revised textbook, one in the Aerospace Education II series, provides answers to many questions related to airplanes and properties of air flight. The first chapter provides a description of aerodynamic forces and deals with concepts such as acceleration, velocity, and forces of flight. The second chapter is devoted to the discussion of…

Elmer, James D.

95

Theory of Aircraft Flight. Aerospace Education II.  

ERIC Educational Resources Information Center

The textbook provides answers to many questions related to airplanes and properties of air flight. The first chapter provides a description of aerodynamic forces and deals with concepts such as acceleration, velocity, and forces of flight. The second chapter is devoted to the discussion of properties of the atmosphere. How different…

Glascoff, W. G., III

96

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

97

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

98

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

99

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

100

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

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

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

103

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

104

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

105

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

106

Flight test data for light aircraft spoiler roll control systems  

NASA Technical Reports Server (NTRS)

The results of flight tests to determine the characteristics of spoiler roll control systems on three different light aircraft are summarized. Comparisons are made with wind tunnel data where available. Flight tests indicate that excellent roll characteristics can be achieved with spoilers. Yaw coupling with roll control inputs is virtually eliminated. Roll rates remain high when flaps are deployed at low speed. Very mild nonlinearities in control effectiveness exist, and there was no deadband or lag detected.

Kohlman, D. L.

1977-01-01

107

Dryden B-52 Launch Aircraft in Flight over Dryden  

NASA Technical Reports Server (NTRS)

NASA's venerable B-52 mothership flies over the main building at the Dryden Flight Research Center, Edwards, California. The B-52, used for launching experimental aircraft and for other flight research projects, has been a familiar sight in the skies over Edwards for more than 40 years and has also been both the oldest B-52 still flying and the aircraft with the lowest flight time of any B-52. NASA B-52, Tail Number 008, is an air launch carrier aircraft, 'mothership,' as well as a research aircraft platform that has been used on a variety of research projects. The aircraft, a 'B' model built in 1952 and first flown on June 11, 1955, is the oldest B-52 in flying status and has been used on some of the most significant research projects in aerospace history. Some of the significant projects supported by B-52 008 include the X-15, the lifting bodies, HiMAT (highly maneuverable aircraft technology), Pegasus, validation of parachute systems developed for the space shuttle program (solid-rocket-booster recovery system and the orbiter drag chute system), and the X-38. The B-52 served as the launch vehicle on 106 X-15 flights and flew a total of 159 captive-carry and launch missions in support of that program from June 1959 to October 1968. Information gained from the highly successful X-15 program contributed to the Mercury, Gemini, and Apollo human spaceflight programs as well as space shuttle development. Between 1966 and 1975, the B-52 served as the launch aircraft for 127 of the 144 wingless lifting body flights. In the 1970s and 1980s, the B-52 was the launch aircraft for several aircraft at what is now the Dryden Flight Research Center, Edwards, California, to study spin-stall, high-angle-of attack, and maneuvering characteristics. These included the 3/8-scale F-15/spin research vehicle (SRV), the HiMAT (Highly Maneuverable Aircraft Technology) research vehicle, and the DAST (drones for aerodynamic and structural testing). The aircraft supported the development of parachute recovery systems used to recover the space shuttle solid rocket booster casings. It also supported eight orbiter (space shuttle) drag chute tests in 1990. In addition, the B-52 served as the air launch platform for the first six Pegasus space boosters. During its many years of service, the B-52 has undergone several modifications. The first major modification was made by North American Aviation (now part of Boeing) in support of the X-15 program. This involved creating a launch-panel-operator station for monitoring the status of the test vehicle being carried, cutting a large notch in the right inboard wing flap to accommodate the vertical tail of the X-15 aircraft, and installing a wing pylon that enables the B-52 to carry research vehicles and test articles to be air-launched/dropped. Located on the right wing, between the inboard engine pylon and the fuselage, this wing pylon was subjected to extensive testing prior to its use. For each test vehicle the B-52 carried, minor changes were made to the launch-panel operator's station. Built originally by the Boeing Company, the NASA B-52 is powered by eight Pratt & Whitney J57-19 turbojet engines, each of which produce 12,000 pounds of thrust. The aircraft's normal launch speed has been Mach 0.8 (about 530 miles per hour) and its normal drop altitude has been 40,000 to 45,000 feet. It is 156 feet long and has a wing span of 185 feet. The heaviest load it has carried was the No. 2 X-15 aircraft at 53,100 pounds. Project manager for the aircraft is Roy Bryant.

1996-01-01

108

LFC leading edge glove flight: Aircraft modification design, test article development and systems integration  

NASA Technical Reports Server (NTRS)

Reduction of skin friction drag by suction of boundary layer air to maintain laminar flow has been known since Prandtl's published work in 1904. The dramatic increases in fuel costs and the potential for periods of limited fuel availability provided the impetus to explore technologies to reduce transport aircraft fuel consumption. NASA sponsored the Aircraft Energy Efficiency (ACEE) program in 1976 to develop technologies to improve fuel efficiency. This report documents the Lockheed-Georgia Company accomplishments in designing and fabricating a leading-edge flight test article incorporating boundary layer suction slots to be flown by NASA on their modified JetStar aircraft. Lockheed-Georgia Company performed as the integration contractor to design the JetStar aircraft modification to accept both a Lockheed and a McDonnell Douglas flight test article. McDonnell Douglas uses a porous skin concept. The report describes aerodynamic analyses, fabrication techniques, JetStar modifications, instrumentation requirements, and structural analyses and testing for the Lockheed test article. NASA will flight test the two LFC leading-edge test articles in a simulated commercial environment over a 6 to 8 month period in 1984. The objective of the flight test program is to evaluate the effectiveness of LFC leading-edge systems in reducing skin friction drag and consequently improving fuel efficiency.

Etchberger, F. R.

1983-01-01

109

System identification methods for aircraft flight control development and validation  

NASA Technical Reports Server (NTRS)

System-identification methods compose a mathematical model, or series of models, from measurements of inputs and outputs of dynamic systems. The extracted models allow the characterization of the response of the overall aircraft or component subsystem behavior, such as actuators and on-board signal processing algorithms. This paper discusses the use of frequency-domain system-identification methods for the development and integration of aircraft flight-control systems. The extraction and analysis of models of varying complexity from nonparametric frequency-responses to transfer-functions and high-order state-space representations is illustrated using the Comprehensive Identification from FrEquency Responses (CIFER) system-identification facility. Results are presented for test data of numerous flight and simulation programs at the Ames Research Center including rotorcraft, fixed-wing aircraft, advanced short takeoff and vertical landing (ASTOVL), vertical/short takeoff and landing (V/STOL), tiltrotor aircraft, and rotor experiments in the wind tunnel. Excellent system characterization and dynamic response prediction is achieved for this wide class of systems. Examples illustrate the role of system-identification technology in providing an integrated flow of dynamic response data around the entire life-cycle of aircraft development from initial specifications, through simulation and bench testing, and into flight-test optimization.

Tischler, Mark B.

1995-01-01

110

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

111

Aircraft Instrument, Fire Protection, Warning, Communication, Navigation and Cabin Atmosphere Control System (Course Outline), Aviation Mechanics 3 (Air Frame): 9067.04.  

ERIC Educational Resources Information Center

This document presents an outline for a 135-hour course designed to familiarize the student with manipulative skills and theoretical knowledge concerning aircraft instrument systems like major flight and engine instruments; fire protection and fire fighting systems; warning systems and navigation systems; aircraft cabin control systems, such as…

Dade County Public Schools, Miami, FL.

112

Flight and Maintenance Planning of Military Aircraft for Maximum Fleet Availability  

Microsoft Academic Search

Every aircraft, military or civilian, must be grounded for maintenance after it has completed a certain number of flight hours since its last maintenance check. Flight and maintenance planning (FMP) of military aircraft addresses the problem of deciding which available aircraft to fly and for how long, and which grounded aircraft to perform maintenance operations on, in a group of

George Kozanidis

113

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

114

Flight mechanics of a tailless articulated wing aircraft.  

PubMed

This paper investigates the flight mechanics of a micro aerial vehicle without a vertical tail in an effort to reverse-engineer the agility of avian flight. The key to stability and control of such a tailless aircraft lies in the ability to control the incidence angles and dihedral angles of both wings independently. The dihedral angles can be varied symmetrically on both wings to control aircraft speed independently of the angle of attack and flight path angle, while asymmetric dihedral can be used to control yaw in the absence of a vertical stabilizer. It is shown that wing dihedral angles alone can effectively regulate sideslip during rapid turns and generate a wide range of equilibrium turn rates while maintaining a constant flight speed and regulating sideslip. Numerical continuation and bifurcation analysis are used to compute trim states and assess their stability. This paper lays the foundation for design and stability analysis of a flapping wing aircraft that can switch rapidly from flapping to gliding flight for agile manoeuvring in a constrained environment. PMID:21487173

Paranjape, Aditya A; Chung, Soon-Jo; Selig, Michael S

2011-06-01

115

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

116

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

117

STOVL aircraft simulation for integrated flight and propulsion control research  

NASA Technical Reports Server (NTRS)

The United States is in the initial stages of committing to a national program to develop a supersonic short takeoff and vertical landing (STOVL) aircraft. The goal of the propulsion community in this effort is to have the enabling propulsion technologies for this type aircraft in place to permit a low risk decision regarding the initiation of a research STOVL supersonic attack/fighter aircraft in the late mid-90's. This technology will effectively integrate, enhance, and extend the supersonic cruise, STOVL and fighter/attack programs to enable U.S. industry to develop a revolutionary supersonic short takeoff and vertical landing fighter/attack aircraft in the post-ATF period. A joint NASA Lewis and NASA Ames research program, with the objective of developing and validating technology for integrated-flight propulsion control design methodologies for short takeoff and vertical landing (STOVL) aircraft, was planned and is underway. This program, the NASA Supersonic STOVL Integrated Flight-Propulsion Controls Program, is a major element of the overall NASA-Lewis Supersonic STOVL Propulsion Technology Program. It uses an integrated approach to develop an integrated program to achieve integrated flight-propulsion control technology. Essential elements of the integrated controls research program are realtime simulations of the integrated aircraft and propulsion systems which will be used in integrated control concept development and evaluations. This paper describes pertinent parts of the research program leading up to the related realtime simulation development and remarks on the simulation structure to accommodate propulsion system hardware drop-in for real system evaluation.

Mihaloew, James R.; Drummond, Colin K.

1989-01-01

118

An Indispensable Ingredient: Flight Research and Aircraft Design  

NASA Technical Reports Server (NTRS)

Flight research-the art of flying actual vehicles in the atmosphere in order to collect data about their behavior-has played a historic and decisive role in the design of aircraft. Naturally, wind tunnel experiments, computational fluid dynamics, and mathematical analyses all informed the judgments of the individuals who conceived of new aircraft. But flight research has offered moments of realization found in no other method. Engineer Dale Reed and research pilot Milt Thompson experienced one such epiphany on March 1, 1963, at the National Aeronautics and Space Administration s Dryden Flight Research Center in Edwards, California. On that date, Thompson sat in the cockpit of a small, simple, gumdrop-shaped aircraft known as the M2-F1, lashed by a long towline to a late-model Pontiac Catalina. As the Pontiac raced across Rogers Dry Lake, it eventually gained enough speed to make the M2-F1 airborne. Thompson braced himself for the world s first flight in a vehicle of its kind, called a lifting body because of its high lift-to-drag ratio. Reed later recounted what he saw:

Gorn, Michael H.

2003-01-01

119

Aircraft automatic flight control system with model inversion  

NASA Technical Reports Server (NTRS)

A simulator study was conducted to verify the advantages of a Newton-Raphson model-inversion technique as a design basis for an automatic trajectory control system in an aircraft with highly nonlinear characteristics. The simulation employed a detailed mathematical model of the aerodynamic and propulsion system performance characteristics of a vertical-attitude takeoff and landing tactical aircraft. The results obtained confirm satisfactory control system performance over a large portion of the flight envelope. System response to wind gusts was satisfactory for various plausible combinations of wind magnitude and direction.

Smith, G. A.; Meyer, George

1990-01-01

120

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

121

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

122

Development and Flight Testing of a Neural Network Based Flight Control System on the NF-15B Aircraft  

NASA Technical Reports Server (NTRS)

The Intelligent Flight Control System (IFCS) project at the NASA Dryden Flight Research Center, Edwards AFB, CA, has been investigating the use of neural network based adaptive control on a unique NF-15B test aircraft. The IFCS neural network is a software processor that stores measured aircraft response information to dynamically alter flight control gains. In 2006, the neural network was engaged and allowed to learn in real time to dynamically alter the aircraft handling qualities characteristics in the presence of actual aerodynamic failure conditions injected into the aircraft through the flight control system. The use of neural network and similar adaptive technologies in the design of highly fault and damage tolerant flight control systems shows promise in making future aircraft far more survivable than current technology allows. This paper will present the results of the IFCS flight test program conducted at the NASA Dryden Flight Research Center in 2006, with emphasis on challenges encountered and lessons learned.

Bomben, Craig R.; Smolka, James W.; Bosworth, John T.; Silliams-Hayes, Peggy S.; Burken, John J.; Larson, Richard R.; Buschbacher, Mark J.; Maliska, Heather A.

2006-01-01

123

Overview of the preparation and use of an OV-10 aircraft for wake vortex hazards flight experiments  

NASA Technical Reports Server (NTRS)

An overview is presented of the development, use, and current flight-test status of a highly instrumented North American Rockwell OV-10A Bronco as a wake-vortex-hazards research aircraft. A description of the operational requirements and measurements criteria, the resulting instrumentation systems and aircraft modifications, system-calibration and research flights completed to date, and current flight status are included. These experiments are being conducted by the National Aeronautics and Space Administration as part of an effort to provide the technology to safely improve the capacity of the nation's air transportation system and specifically to provide key data in understanding and predicting wake vortex decay, transport characteristics, and the dynamics of encountering wake turbulence. The OV-10A performs several roles including meteorological measurements platform, wake-decay quantifier, and trajectory-quantifier for wake encounters. Extensive research instrumentation systems include multiple airdata sensors, video cameras with cockpit displays, aircraft state and control-position measurements, inertial aircraft-position measurements, meteorological measurements, and an on-board personal computer for real-time processing and cockpit display of research data. To date, several of the preliminary system check flights and two meteorological-measurements deployments have been completed. Several wake encounter and wake-decay-measurements flights are planned for the fall of 1995.

Stuever, Robert A.; Stewart, Eric C.; Rivers, Robert A.

1995-01-01

124

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

125

Instrument Display Visual Angles for Conventional Aircraft and the MQ-9 Ground Control Station  

NASA Technical Reports Server (NTRS)

Aircraft instrument panels should be designed such that primary displays are in optimal viewing location to minimize pilot perception and response time. Human Factors engineers define three zones (i.e. "cones") of visual location: 1) "Easy Eye Movement" (foveal vision); 2) "Maximum Eye Movement" (peripheral vision with saccades), and 3) "Head Movement" (head movement required). Instrument display visual angles were measured to determine how well conventional aircraft (T-34, T-38, F- 15B, F-16XL, F/A-18A, U-2D, ER-2, King Air, G-III, B-52H, DC-10, B747-SCA) and the MQ-9 ground control station (GCS) complied with these standards, and how they compared with each other. Methods: Selected instrument parameters included: attitude, pitch, bank, power, airspeed, altitude, vertical speed, heading, turn rate, slip/skid, AOA, flight path, latitude, longitude, course, bearing, range and time. Vertical and horizontal visual angles for each component were measured from the pilot s eye position in each system. Results: The vertical visual angles of displays in conventional aircraft lay within the cone of "Easy Eye Movement" for all but three of the parameters measured, and almost all of the horizontal visual angles fell within this range. All conventional vertical and horizontal visual angles lay within the cone of "Maximum Eye Movement". However, most instrument vertical visual angles of the MQ-9 GCS lay outside the cone of "Easy Eye Movement", though all were within the cone of "Maximum Eye Movement". All the horizontal visual angles for the MQ-9 GCS were within the cone of "Easy Eye Movement". Discussion: Most instrument displays in conventional aircraft lay within the cone of "Easy Eye Movement", though mission-critical instruments sometimes displaced less important instruments outside this area. Many of the MQ-9 GCS systems lay outside this area. Specific training for MQ-9 pilots may be needed to avoid increased response time and potential error during flight.

Bendrick, Gregg A.; Kamine, Tovy Haber

2008-01-01

126

Perseus A High Altitude Remotely Piloted Aircraft being Towed in Flight  

NASA Technical Reports Server (NTRS)

Perseus A, a remotely piloted, high-altitude research vehicle designed by Aurora Flight Sciences Corp., takes off from Rogers Dry Lake at the Dryden Flight Research Center, Edwards, California. The Perseus was towed into the air by a ground vehicle. At about 700 ft. the aircraft was released and the engine turned the propeller to take the plane to its desired altitude. Perseus B is a remotely piloted aircraft developed as a design-performance testbed under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) project. Perseus is one of several flight vehicles involved in the ERAST project. A piston engine, propeller-powered aircraft, Perseus was designed and built by Aurora Flight Sciences Corporation, Manassas, Virginia. The objectives of Perseus B's ERAST flight tests have been to reach and maintain horizontal flight above altitudes of 60,000 feet and demonstrate the capability to fly missions lasting from 8 to 24 hours, depending on payload and altitude requirements. The Perseus B aircraft established an unofficial altitude record for a single-engine, propeller-driven, remotely piloted aircraft on June 27, 1998. It reached an altitude of 60,280 feet. In 1999, several modifications were made to the Perseus aircraft including engine, avionics, and flight-control-system improvements. These improvements were evaluated in a series of operational readiness and test missions at the Dryden Flight Research Center, Edwards, California. Perseus is a high-wing monoplane with a conventional tail design. Its narrow, straight, high-aspect-ratio wing is mounted atop the fuselage. The aircraft is pusher-designed with the propeller mounted in the rear. This design allows for interchangeable scientific-instrument payloads to be placed in the forward fuselage. The design also allows for unobstructed airflow to the sensors and other devices mounted in the payload compartment. The Perseus B that underwent test and development in 1999 was the third generation of the Perseus design, which began with the Perseus Proof-Of-Concept aircraft. Perseus was initially developed as part of NASA's Small High-Altitude Science Aircraft (SHASA) program, which later evolved into the ERAST project. The Perseus Proof-Of-Concept aircraft first flew in November 1991 and made three low-altitude flights within a month to validate the Perseus aerodynamic model and flight control systems. Next came the redesigned Perseus A, which incorporated a closed-cycle combustion system that mixed oxygen carried aboard the aircraft with engine exhaust to compensate for the thin air at high altitudes. The Perseus A was towed into the air by a ground vehicle and its engine started after it became airborne. Prior to landing, the engine was stopped, the propeller locked in horizontal position, and the Perseus A glided to a landing on its unique bicycle-type landing gear. Two Perseus A aircraft were built and made 21 flights in 1993-1994. One of the Perseus A aircraft reached over 50,000 feet in altitude on its third test flight. Although one of the Perseus A aircraft was destroyed in a crash after a vertical gyroscope failed in flight, the other aircraft completed its test program and remains on display at Aurora's facility in Manassas. Perseus B first flew Oct. 7, 1994, and made two flights in 1996 before being damaged in a hard landing on the dry lakebed after a propeller shaft failure. After a number of improvements and upgrades-including extending the original 58.5-foot wingspan to 71.5 feet to enhance high-altitude performance--the Perseus B returned to Dryden in the spring of 1998 for a series of four flights. Thereafter, a series of modifications were made including external fuel pods on the wing that more than doubled the fuel capacity to 100 gallons. Engine power was increased by more than 20 percent by boosting the turbocharger output. Fuel consumption was reduced with fuel control modifications and a leaner fuel-air mixture that did not compromise power. The aircraft again crashed on Oct. 1, 1999, near Barstow, California, suffering moderate damage to th

1994-01-01

127

Test-engine and inlet performance of an aircraft used for investigating flight effects on fan noise  

NASA Technical Reports Server (NTRS)

As part of the NASA Flight Effects on Fan Noise Program, a Grumman OV-1B Mohawk aircraft was modified to carry a modified and instrumented Pratt & Whitney JT15D-1 turbofan engine. Onboard flight data, together with simultaneously measured farfield acoustic data, comprise a flight data base to which JT15D-1 static and wind-tunnel data are compared. The overall objective is to improve the ability to use ground-based facilities for the prediction of flight inlet radiated noise. This report describes the hardware and presents performance results for the research engine.

Golub, R. A.; Preisser, J. S.

1984-01-01

128

Nonlinear simulation of a flexible aircraft in maneuvering flight  

NASA Technical Reports Server (NTRS)

A mathematical model integrating nonlinear rigid-body flight mechanics and linear aeroelastic dynamics is examined; the equations of motion for an elastic aircraft in accelerated flight are developed using Lagrangian mechanics. This approach is used to construct a simulation model of an F/A-18 (configured with tip missiles) which includes angular/elastic inertial coupling (IC). In general, the elastic modes significantly affected by IC were aerodynamically decoupled from the rest of the model. The affected modes were those which induced changes in total aircraft mass distribution. The elastic effect is noticeable if deformation-induced mass distribution changes are significant with respect to modal mass and modal frequencies. A modal parameter is presented which characterizes the level of IC between elastic momentum and rigid-body angular momentum.

Buttrill, Carey S.; Arbuckle, P. Douglas; Zeiler, Thomas A.

1987-01-01

129

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

130

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

131

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

132

Advanced instrumentation for aircraft icing research  

NASA Technical Reports Server (NTRS)

A compact and rugged probe based on the phase Doppler method was evaluated as a means for characterizing icing clouds using airborne platforms and for advancing aircraft icing research in large scale wind tunnels. The Phase Doppler Particle Analyzer (PDPA) upon which the new probe was based is now widely recognized as an accurate method for the complete characterization of sprays. The prototype fiber optic-based probe was evaluated in simulated aircraft icing clouds and found to have the qualities essential to providing information that will advance aircraft icing research. Measurement comparisons of the size and velocity distributions made with the standard PDPA and the fiber optic probe were in excellent agreement as were the measurements of number density and liquid water content. Preliminary testing in the NASA Lewis Icing Research Tunnel (IRT) produced reasonable results but revealed some problems with vibration and signal quality at high speeds. The cause of these problems were identified and design changes were proposed to eliminate the shortcomings of the probe.

Bachalo, W.; Smith, J.; Rudoff, R.

1990-01-01

133

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

134

14 CFR 61.417 - Will my flight instructor certificate with a sport pilot rating list aircraft category and class...  

Code of Federal Regulations, 2011 CFR

...my flight instructor certificate with a sport pilot rating list aircraft category and...INSTRUCTORS Flight Instructors With a Sport Pilot Rating § 61.417 Will my flight instructor certificate with a sport pilot rating list aircraft category...

2011-01-01

135

14 CFR 61.417 - Will my flight instructor certificate with a sport pilot rating list aircraft category and class...  

Code of Federal Regulations, 2012 CFR

...my flight instructor certificate with a sport pilot rating list aircraft category and...INSTRUCTORS Flight Instructors With a Sport Pilot Rating § 61.417 Will my flight instructor certificate with a sport pilot rating list aircraft category...

2012-01-01

136

14 CFR 61.417 - Will my flight instructor certificate with a sport pilot rating list aircraft category and class...  

Code of Federal Regulations, 2013 CFR

...my flight instructor certificate with a sport pilot rating list aircraft category and...INSTRUCTORS Flight Instructors With a Sport Pilot Rating § 61.417 Will my flight instructor certificate with a sport pilot rating list aircraft category...

2013-01-01

137

14 CFR 61.417 - Will my flight instructor certificate with a sport pilot rating list aircraft category and class...  

Code of Federal Regulations, 2014 CFR

...my flight instructor certificate with a sport pilot rating list aircraft category and...INSTRUCTORS Flight Instructors With a Sport Pilot Rating § 61.417 Will my flight instructor certificate with a sport pilot rating list aircraft category...

2014-01-01

138

14 CFR 61.417 - Will my flight instructor certificate with a sport pilot rating list aircraft category and class...  

Code of Federal Regulations, 2010 CFR

...my flight instructor certificate with a sport pilot rating list aircraft category and...INSTRUCTORS Flight Instructors With a Sport Pilot Rating § 61.417 Will my flight instructor certificate with a sport pilot rating list aircraft category...

2010-01-01

139

Flight instruments and helmet-mounted SWIR imaging systems  

NASA Astrophysics Data System (ADS)

Night vision technology has experienced significant advances in the last two decades. Night vision goggles (NVGs) based on gallium arsenide (GaAs) continues to raise the bar for alternative technologies. Resolution, gain, sensitivity have all improved; the image quality through these devices is nothing less than incredible. Panoramic NVGs and enhanced NVGs are examples of recent advances that increase the warfighter capabilities. Even with these advances, alternative night vision devices such as solid-state indium gallium arsenide (InGaAs) focal plane arrays are under development for helmet-mounted imaging systems. The InGaAs imaging system offers advantages over the existing NVGs. Two key advantages are; (1) the new system produces digital image data, and (2) the new system is sensitive to energy in the shortwave infrared (SWIR) spectrum. While it is tempting to contrast the performance of these digital systems to the existing NVGs, the advantage of different spectral detection bands leads to the conclusion that the technologies are less competitive and more synergistic. It is likely, by the end of the decade, pilots within a cockpit will use multi-band devices. As such, flight decks will need to be compatible with both NVGs and SWIR imaging systems. Insertion of NVGs in aircraft during the late 70's and early 80's resulted in many "lessons learned" concerning instrument compatibility with NVGs. These "lessons learned" ultimately resulted in specifications such as MIL-L-85762A and MIL-STD-3009. These specifications are now used throughout industry to produce NVG-compatible illuminated instruments and displays for both military and civilian applications. Inserting a SWIR imaging device in a cockpit will require similar consideration. A project evaluating flight deck instrument compatibility with SWIR devices is currently ongoing; aspects of this evaluation are described in this paper. This project is sponsored by the Air Force Research Laboratory (AFRL).

Robinson, Tim; Green, John; Jacobson, Mickey; Grabski, Greg

2011-06-01

140

FLIGHT AND MAINTENANCE PLANNING OF MILITARY AIRCRAFT FOR MAXIMUM FLEET AVAILABILITY: A BIOBJECTIVE MODEL  

Microsoft Academic Search

Flight and maintenance planning (FMP) of military aircraft addresses the problem of deciding which available aircraft to fly and for how long and which grounded aircraft to perform maintenance operations on, in a set of aircraft that comprise a combat unit. The objective is to achieve maximum availability of the unit over the planning horizon. The large number of parameters

George Kozanidis; Athanasios Skipis; Pedion Areos

2006-01-01

141

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

142

Deflection-Based Aircraft Structural Loads Estimation with Comparison to Flight  

NASA Technical Reports Server (NTRS)

Traditional techniques in structural load measurement entail the correlation of a known load with strain-gage output from the individual components of a structure or machine. The use of strain gages has proved successful and is considered the standard approach for load measurement. However, remotely measuring aerodynamic loads using deflection measurement systems to determine aeroelastic deformation as a substitute to strain gages may yield lower testing costs while improving aircraft performance through reduced instrumentation weight. With a reliable strain and structural deformation measurement system this technique was examined. The objective of this study was to explore the utility of a deflection-based load estimation, using the active aeroelastic wing F/A-18 aircraft. Calibration data from ground tests performed on the aircraft were used to derive left wing-root and wing-fold bending-moment and torque load equations based on strain gages, however, for this study, point deflections were used to derive deflection-based load equations. Comparisons between the strain-gage and deflection-based methods are presented. Flight data from the phase-1 active aeroelastic wing flight program were used to validate the deflection-based load estimation method. Flight validation revealed a strong bending-moment correlation and slightly weaker torque correlation. Development of current techniques, and future studies are discussed.

Lizotte, Andrew M.; Lokos, William A.

2005-01-01

143

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

144

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

145

Pressure drop in tubing in aircraft instrument installations  

NASA Technical Reports Server (NTRS)

The theoretical basis of calculation of pressure drop in tubing is reviewed briefly. The effect of pressure drop in connecting tubing upon the operation and indication of aircraft instruments is discussed. Approximate equations are developed, and charts and tables based upon them are presented for use in designing installations of altimeters, air-speed indicators, rate-of-climb indicators, and air-driven gyroscopic instruments.

Wildhack, W A

1937-01-01

146

Instrument Display Visual Angles for Conventional Aircraft and the MQ-9 Ground Control Station  

NASA Technical Reports Server (NTRS)

Aircraft instrument panels should be designed such that primary displays are in optimal viewing location to minimize pilot perception and response time. Human Factors engineers define three zones (i.e. cones ) of visual location: 1) "Easy Eye Movement" (foveal vision); 2) "Maximum Eye Movement" (peripheral vision with saccades), and 3) "Head Movement (head movement required). Instrument display visual angles were measured to determine how well conventional aircraft (T-34, T-38, F- 15B, F-16XL, F/A-18A, U-2D, ER-2, King Air, G-III, B-52H, DC-10, B747-SCA) and the MQ-9 ground control station (GCS) complied with these standards, and how they compared with each other. Selected instrument parameters included: attitude, pitch, bank, power, airspeed, altitude, vertical speed, heading, turn rate, slip/skid, AOA, flight path, latitude, longitude, course, bearing, range and time. Vertical and horizontal visual angles for each component were measured from the pilot s eye position in each system. The vertical visual angles of displays in conventional aircraft lay within the cone of "Easy Eye Movement" for all but three of the parameters measured, and almost all of the horizontal visual angles fell within this range. All conventional vertical and horizontal visual angles lay within the cone of Maximum Eye Movement. However, most instrument vertical visual angles of the MQ-9 GCS lay outside the cone of Easy Eye Movement, though all were within the cone of Maximum Eye Movement. All the horizontal visual angles for the MQ-9 GCS were within the cone of "Easy Eye Movement". Most instrument displays in conventional aircraft lay within the cone of Easy Eye Movement, though mission-critical instruments sometimes displaced less important instruments outside this area. Many of the MQ-9 GCS systems lay outside this area. Specific training for MQ-9 pilots may be needed to avoid increased response time and potential error during flight. The learning objectives include: 1) Know three physiologic cones of eye/head movement; 2) Understand how instrument displays comply with these design principles in conventional aircraft and an uninhabited aerial vehicle system. Which of the following is NOT a recognized physiologic principle of instrument display design? Cone of Easy Eye Movement 2) Cone of Binocular Eye Movement 3) Cone of Maximum Eye Movement 4) Cone of Head Movement 5) None of the above. Answer: # 2) Cone of Binocular Eye Movement

Kamine, Tovy Haber; Bendrick, Gregg A.

2008-01-01

147

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

148

Altus I aircraft in flight, retracting landing gear after takeoff  

NASA Technical Reports Server (NTRS)

The landing gear of the remotely piloted Altus I aircraft retracts into the fuselage after takeoff from Rogers Dry Lake adjacent to NASA's Dryden Flight Research Center, Edwards, Calif. The short series of test flights sponsored by the Naval Postgraduate School in early August, 1997, was designed to demonstrate the ability of the experimental craft to cruise at altitudes above 40,000 feet for sustained durations. On its final flight Aug. 15, the Altus I reached an altitude of 43,500 feet. The Altus I and its sister ship, the Altus II, are variants of the Predator surveillance drone built by General Atomics/Aeronautical Systems, Inc. They are designed for high-altitude, long-duration scientific sampling missions. The Altus I incorporates a single-stage turbocharger, while the Altus II, built for NASA's Environmental Research Aircraft and Sensor Technology project, sports a two-stage turbocharger to enable the craft to fly at altitudes above 55,000 feet.

1997-01-01

149

Satellite images to aircraft in flight. [GEOS image transmission feasibility analysis  

NASA Technical Reports Server (NTRS)

A study has been initiated to evaluate the feasibility of transmitting selected GOES images to aircraft in flight. Pertinent observations that could be made from satellite images on board aircraft include jet stream activity, cloud/wind motion, cloud temperatures, tropical storm activity, and location of severe weather. The basic features of the Satellite Aircraft Flight Environment System (SAFES) are described. This system uses East GOES and West GOES satellite images, which are interpreted, enhanced, and then retransmitted to designated aircraft.

Camp, D.; Luers, J. K.; Kadlec, P. W.

1977-01-01

150

Flight assessment of a large supersonic drone aircraft for research use  

NASA Technical Reports Server (NTRS)

An assessment is made of the capabilities of the BQM-34E supersonic drone aircraft as a test bed research vehicle. This assessment is made based on a flight conducted for the purpose of obtaining flight test measurements of wing loads at various maneuver flight conditions. Flight plan preparation, flight simulation, and conduct of the flight test are discussed along with a presentation of the test data obtained and an evaluation of how closely the flight test followed the test plan.

Eckstrom, C. V.; Peele, E. L.

1974-01-01

151

Emergency in-flight egress opening for general aviation aircraft  

NASA Technical Reports Server (NTRS)

In support of a stall/spin research program, an emergency in-flight egress system is being installed in a light general aviation airplane. To avoid a major structural redesign for a mechanical door, an add-on 11.2 kg pyrotechnic-actuated system was developed to create an opening in the existing structure. The airplane skin will be 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 will be 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 mock-ups, and an actual aircraft fuselage. These tests proved explosive sizing/severance margins, explosive initiation, explosive product containment, and system dynamics.

Bement, L. J.

1980-01-01

152

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

153

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

NASA Technical Reports Server (NTRS)

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

Oneill-Rood, Nora; Glover, Richard D.

1990-01-01

154

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

155

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

156

Flight testing of a remotely piloted vehicle for aircraft parameter estimation purposes  

NASA Astrophysics Data System (ADS)

The contribution of this research effort was to show that a reliable RPV could be built, tested, and successfully used for flight testing and parameter estimation purposes, in an academic setting. This was a fundamental step towards the creation of an automated Unmanned Aerial Vehicle (UAV). This research project was divided into four phases. Phase one involved the construction, development, and initial flight of a Remotely Piloted Vehicle (RPV), the West Virginia University (WVU) Boeing 777 (B777) aircraft. This phase included the creation of an onboard instrumentation system to provide aircraft flight data. The objective of the second phase was to estimate the longitudinal and lateral-directional stability and control derivatives from actual flight data for the B777 model. This involved performing and recording flight test maneuvers used for analysis of the longitudinal and lateral-directional estimates. Flight maneuvers included control surface doublets produced by the elevator, aileron, and rudder controls. A parameter estimation program known as pEst, developed at NASA Dryden Flight Research Center (DFRC), was used to compute the off-line estimates of parameters from collected flight data. This estimation software uses the Maximum Likelihood (ML) method with a Newton-Raphson (NR) minimization algorithm. The mathematical model used a traditional static and dynamic derivative buildup. Phase three focused on comparing a linear model obtained from the phase two ML estimates, with linear models obtained from a (i) Batch Least Squares Technique (BLS) and (ii) a technique from the Matlab system identification toolbox. Historically, aircraft parameter estimation has been performed off-line using recorded flight data from specifically designed maneuvers. In recent years, several on-line parameter identification techniques have been evaluated for real-time on-line applications. Along this research line, a novel contribution of this work was to compare the off-line estimation results with results obtained using a recently introduced frequency based on-line estimation method. Specifically, phase four focused on comparing the ML results with a frequency domain based on-line estimation technique. The RPV vehicle and payload was designed and constructed with the combined efforts of WVU researchers, graduate and undergraduate students of the Mechanical and Aerospace Engineering Department, and a private sub-contractor, Craig Aviation.

Seanor, Brad A.

2002-01-01

157

Stability derivative extraction from flight test data for a general aviation aircraft  

E-print Network

The Gulfstream Commander 700 (N700AE) aircraft owned by the Texas A&M Flight Mechanics Laboratory (FML) is currently being modeled on the Engineering Flight Simulator (EFS) for testing of an integrated cockpit system for general aviation (GA...

Randall, Brian Edward

1996-01-01

158

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 ...

159

5 CFR 532.267 - Special wage schedules for aircraft, electronic, and optical instrument overhaul and repair...  

Code of Federal Regulations, 2010 CFR

...schedules for aircraft, electronic, and optical instrument overhaul and repair positions...schedules for aircraft, electronic, and optical instrument overhaul and repair positions...aircraft, electronic equipment, and optical instrument overhaul and repair....

2010-01-01

160

5 CFR 532.267 - Special wage schedules for aircraft, electronic, and optical instrument overhaul and repair...  

Code of Federal Regulations, 2011 CFR

...schedules for aircraft, electronic, and optical instrument overhaul and repair positions...schedules for aircraft, electronic, and optical instrument overhaul and repair positions...aircraft, electronic equipment, and optical instrument overhaul and repair....

2011-01-01

161

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

162

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

163

Flight tests of the total automatic flight control system (Tafcos) concept on a DHC-6 Twin Otter aircraft  

NASA Technical Reports Server (NTRS)

Flight control systems capable of handling the complex operational requirements of the STOL and VTOL aircraft designs as well as designs using active control concepts are considered. Emphasis is placed on the total automatic flight control system (TACOS) (TAFCOS). Flight test results which verified the performance of the system concept are presented.

Wehrend, W. R., Jr.; Meyer, G.

1980-01-01

164

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

165

One of NASA's Two Modified Boeing 747 Shuttle Carrier (SCA) Aircraft in Flight over NASA Dryden Flig  

NASA Technical Reports Server (NTRS)

One of NASA's Boeing 747 Shuttle Carrier Aircraft flies over the Dryden Flight Research Center main building at Edwards Air Force Base, Edwards, California, in May 1999. NASA uses two modified Boeing 747 jetliners, originally manufactured for commercial use, as Space Shuttle Carrier Aircraft (SCA). One is a 747-100 model, while the other is designated a 747-100SR (short range). The two aircraft are identical in appearance and in their performance as Shuttle Carrier Aircraft. The 747 series of aircraft are four-engine intercontinental-range swept-wing 'jumbo jets' that entered commercial service in 1969. The SCAs are used to ferry space shuttle orbiters from landing sites back to the launch complex at the Kennedy Space Center, and also to and from other locations too distant for the orbiters to be delivered by ground transportation. The orbiters are placed atop the SCAs by Mate-Demate Devices, large gantry-like structures which hoist the orbiters off the ground for post-flight servicing, and then mate them with the SCAs for ferry flights. Features which distinguish the two SCAs from standard 747 jetliners are: o Three struts, with associated interior structural strengthening, protruding from the top of the fuselage (two aft, one forward) on which the orbiter is attached o Two additional vertical stabilizers, one on each end of the standard horizontal stabilizer, to enhance directional stability o Removal of all interior furnishings and equipment aft of the forward No. 1 doors o Instrumentation used by SCA flight crews and engineers to monitor orbiter electrical loads during the ferry flights and also during pre- and post-ferry flight operations. The two SCAs are under the operational control of NASA's Johnson Space Center, Houston, Tex. NASA 905 NASA 905 was the first SCA. It was obtained from American Airlines in 1974. Shortly after it was accepted by NASA it was flown in a series of wake vortex research flights at the Dryden Flight Research Center in a study to seek ways of reducing turbulence produced by large aircraft. Pilots flying as much as several miles behind large aircraft have encountered wake turbulence that have caused control problems. The NASA study helped the Federal Aviation Administration modify flight procedures for commercial aircraft during airport approaches and departures. Following the wake vortex studies, NASA 905 was modified by Boeing to its present SCA configuration and the aircraft was returned to Dryden for its role in the 1977 Space Shuttle Approach and Landing Tests (ALT). This series of eight captive and five free flights with the orbiter prototype Enterprise, in addition to ground taxi tests, validated the aircraft's performance as an SCA, in addition to verifying the glide and landing characteristics of the orbiter configuration -- paving the way for orbital flights. A flight crew escape system, consisting of an exit tunnel extending from the flight deck to a hatch in the bottom of the fuselage, was installed during the modifications. The system also included a pyrotechnic system to activate the hatch release and cabin window release mechanisms. The flight crew escape system was removed from the NASA 905 following the successful completion of the ALT program. NASA 905 was the only SCA used by the space shuttle program until November 1990, when NASA 911 was delivered as an SCA. Along with ferrying Enterprise and the flight-rated orbiters between the launch and landing sites and other locations, NASA 905 also ferried Enterprise to Europe for display in England and at the Paris Air Show. NASA 911 The second SCA is designated NASA 911. It was obtained by NASA from Japan Airlines (JAL) in 1989. It was also modified by Boeing Corporation. It was delivered to NASA 20 November 1990.

1999-01-01

166

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

Code of Federal Regulations, 2010 CFR

...2010-10-01 true Aircraft ground and flight risk. 1852.228-70 Section 1852.228-70...228-70 Aircraft ground and flight risk. As prescribed in 1828.370(a...clause is to have the Government assume risks that generally entail unusually...

2010-10-01

167

Analysis of the Cyclotron Facility Calibration and Aircraft Results Obtained by LIULIN-3M Instrument  

NASA Technical Reports Server (NTRS)

The LIULIN-3M instrument is a further development of the LIULIN dosimeter-radiometer, which has been used on the NffR space station in the 1988-1994 time period, The LIULIN-3M is designed for continuous monitoring of the radiation environment during the BION-12 satellite flight in 1999. A semiconductor detector with 1 mm thickness and 1 cm(exp 2) area is used in the instrument. Pulse high analysis technique is used for measurement of the energy losses in the detector. The final data sets from the instrument are the flux and the dose rate for the exposition time and 256 channels of LET spectra if a non-nal coincidence of the particles to the detector is considered. The LIULIN-3M instrument was calibrated by proton fluxes with different energies at the Indiana University Cyclotron Facility in June 1997 and was used for space radiation measurements during commercial aircraft flights. Obtained calibration and flight results are analyzed in the paper.

Dachev, T. P.; Stassinopoulos, E. G.; Tomov, B. T.; Dimitrov, P. G.; Matviichuk, Y. N.; Shurshakov, V. A.; Petrov, V. M.

1998-01-01

168

Wind tunnel and flight test of the XV-15 Tilt Rotor Research Aircraft  

NASA Technical Reports Server (NTRS)

The XV-15 Tilt Rotor Research Aircraft Project involves design, fabrication, and flight testing of two aircraft. This program is currently in the test phase for concept evaluation and substantiation of design. As part of this evaluation, one of the aircraft was tested in the NASA-Ames 40- by 80-foot wind tunnel. The status of testing to date and some of the results of the wind tunnel and flight tests are presented.

Marr, R. L.; Blackman, S.; Weiberg, J. A.; Schroers, L. G.

1979-01-01

169

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

170

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

171

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

172

14 CFR 25.1303 - Flight and navigation instruments.  

Code of Federal Regulations, 2011 CFR

...attitude instrument system useable through flight attitudes of 360° of pitch and roll and installed in accordance with § 121.305(k) of this title. (5) A bank and pitch indicator (gyroscopically stabilized). (6) A direction...

2011-01-01

173

Fiber optic (flight quality) sensors for advanced aircraft propulsion  

NASA Technical Reports Server (NTRS)

Development of flight prototype, fiber-optic sensing system components for measuring nine sensed parameters (three temperatures, two speeds, three positions, and one flame) on an F404-400 aircraft engine is described. Details of each sensor's design, functionality, and environmental testing, and the electro-optics architecture for sensor signal conditioning are presented. Eight different optical sensing techniques were utilized. Design, assembly, and environmental testing of an engine-mounted, electro-optics chassis unit (EOU), providing MIL-C-1553 data output, are related. Interconnection cables and connectors between the EOU and the sensors are identified. Results of sensor/cable/circuitry integrated testing, and installation and ground testing of the sensor system on an engine in October 1993 and April 1994 are given, including comparisons with the engine control system's electrical sensors. Lessons learned about the design, fabrication, testing, and integration of the sensor system components are included.

Poppel, Gary L.

1994-01-01

174

Dynamics of tilting proprotor aircraft in cruise flight  

NASA Technical Reports Server (NTRS)

A nine degree-of-freedom theoretical model is developed for investigations of the dynamics of a proprotor operating in high inflow axial flight on a cantilever wing. The basic characteristics of the rotor high inflow aerodynamics and the resulting rotor aeroelastic behavior are discussed. The problems of classical whirl flutter, the two-bladed rotor, and the influence of the proprotor on the stability derivatives of the aircraft are treated briefly. The influence of various elements of the theoretical model is discussed, including the modeling used for the blade and wing aerodynamics, and the influence of the rotor lag degree of freedom. The results from tests of two full-scale proprotors - a gimballed, stiff-inplane rotor and a hingeless, soft-inplane rotor - are presented; comparisons with the theoretical results show good correlation.

Johnson, W.

1974-01-01

175

Scanning laser aircraft surveillance system for carrier flight operations  

Microsoft Academic Search

The Scanning Laser Aircraft Surveillance System (SLASS) uses two scanning infrared laser beams to illuminate retroreflectors located on aircraft landing gears and hook to determine very precisely the azimuthal, ascension, yaw, roll, and pitch angles of the aircraft in the approach corridor. The range, approach velocity, and aircraft type are also determined. Aircraft configuration is determined by the presence or

Alan A. Vetter; David M. Shemwell; R. I. Gellert; J. Black

1992-01-01

176

Flight control synthesis for flexible aircraft using Eigenspace assignment  

NASA Technical Reports Server (NTRS)

The use of eigenspace assignment techniques to synthesize flight control systems for flexible aircraft is explored. Eigenspace assignment techniques are used to achieve a specified desired eigenspace, chosen to yield desirable system impulse residue magnitudes for selected system responses. Two of these are investigated. The first directly determines constant measurement feedback gains that will yield a close-loop system eigenspace close to a desired eigenspace. The second technique selects quadratic weighting matrices in a linear quadratic control synthesis that will asymptotically yield the close-loop achievable eigenspace. Finally, the possibility of using either of these techniques with state estimation is explored. Application of the methods to synthesize integrated flight-control and structural-mode-control laws for a large flexible aircraft is demonstrated and results discussed. Eigenspace selection criteria based on design goals are discussed, and for the study case it would appear that a desirable eigenspace can be obtained. In addition, the importance of state-space selection is noted along with problems with reduced-order measurement feedback. Since the full-state control laws may be implemented with dynamic compensation (state estimation), the use of reduced-order measurement feedback is less desirable. This is especially true since no change in the transient response from the pilot's input results if state estimation is used appropriately. The potential is also noted for high actuator bandwidth requirements if the linear quadratic synthesis approach is utilized. Even with the actuator pole location selected, a problem with unmodeled modes is noted due to high bandwidth. Some suggestions for future research include investigating how to choose an eigenspace that will achieve certain desired dynamics and stability robustness, determining how the choice of measurements effects synthesis results, and exploring how the phase relationships between desired eigenvector elements effects the synthesis results.

Davidson, J. B.; Schmidt, D. K.

1986-01-01

177

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.

178

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

179

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

180

Applications of the unsteady vortex-lattice method in aircraft aeroelasticity and flight dynamics  

NASA Astrophysics Data System (ADS)

The unsteady vortex-lattice method provides a medium-fidelity tool for the prediction of non-stationary aerodynamic loads in low-speed, but high-Reynolds-number, attached flow conditions. Despite a proven track record in applications where free-wake modelling is critical, other less-computationally expensive potential-flow models, such as the doublet-lattice method and strip theory, have long been favoured in fixed-wing aircraft aeroelasticity and flight dynamics. This paper presents how the unsteady vortex-lattice method can be implemented as an enhanced alternative to those techniques for diverse situations that arise in flexible-aircraft dynamics. A historical review of the methodology is included, with latest developments and practical applications. Different formulations of the aerodynamic equations are outlined, and they are integrated with a nonlinear beam model for the full description of the dynamics of a free-flying flexible vehicle. Nonlinear time-marching solutions capture large wing excursions and wake roll-up, and the linearisation of the equations lends itself to a seamless, monolithic state-space assembly, particularly convenient for stability analysis and flight control system design. The numerical studies emphasise scenarios where the unsteady vortex-lattice method can provide an advantage over other state-of-the-art approaches. Examples of this include unsteady aerodynamics in vehicles with coupled aeroelasticity and flight dynamics, and in lifting surfaces undergoing complex kinematics, large deformations, or in-plane motions. Geometric nonlinearities are shown to play an instrumental, and often counter-intuitive, role in the aircraft dynamics. The unsteady vortex-lattice method is unveiled as a remarkable tool that can successfully incorporate all those effects in the unsteady aerodynamics modelling.

Murua, Joseba; Palacios, Rafael; Graham, J. Michael R.

2012-11-01

181

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

182

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

183

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

184

FAULT TOLERANT FLIGHT CONTROLLER FOR A HIGH PERFORMANCE FIGHTER AIRCRAFT DURING AUTO-LANDING  

Microsoft Academic Search

In this paper the auto-landing problem of a high performance fighter aircraft has been addressed. During landing, the flight path consists of flight segments such as a wing-level flight, a coordinated turn, glide slope descent and finally the flare maneuver and touchdown on the runway. The trajectory segments corresponding to these phases have to be flown in the presence of

NAGARAJ RAMRAO

2007-01-01

185

The Altus II remotely piloted aircraft carried a variety of specialized instruments and cameras duri  

NASA Technical Reports Server (NTRS)

The Altus II remotely piloted aircraft carried a variety of specialized instruments and cameras during a lightning study over Florida during the summer of 2002, including one sensor mounted on a boom extending from Altus' nose. The Altus Cumulus Electrification Study (ACES), led by Dr. Richard Blakeslee of NASA Marshall Space Flight center, focused on the collection of electrical, magnetic and optical measurements of thunderstorms. Data collected will help scientists understand the development and life cycles of thunderstorms, which in turn may allow meteorologists to more accurately predict when destructive storms may hit. The Altus II, built by General Atomics Aeronautical Systems, Inc., is one of several remotely operated aircraft developed and matured under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) program. The program focused on developing airframe, propulsion, control system and communications technologies to allow unmanned aerial vehicles (UAVs) to operate at very high altitudes for long durations while carrying a variety of sensors, cameras or other instruments for science experiments, surveillance or telecommunications relay missions.

2002-01-01

186

Flight control system development and flight test experience with the F-111 mission adaptive wing aircraft  

NASA Technical Reports Server (NTRS)

The wing on the NASA F-111 transonic aircraft technology airplane was modified to provide flexible leading and trailing edge flaps. This wing is known as the mission adaptive wing (MAW) because aerodynamic efficiency can be maintained at all speeds. Unlike a conventional wing, the MAW has no spoilers, external flap hinges, or fairings to break the smooth contour. The leading edge flaps and three-segment trailing edge flaps are controlled by a redundant fly-by-wire control system that features a dual digital primary system architecture providing roll and symmetric commands to the MAW control surfaces. A segregated analog backup system is provided in the event of a primary system failure. This paper discusses the design, development, testing, qualification, and flight test experience of the MAW primary and backup flight control systems.

Larson, R. R.

1986-01-01

187

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

188

Scanning laser aircraft surveillance system for carrier flight operations  

NASA Astrophysics Data System (ADS)

The Scanning Laser Aircraft Surveillance System (SLASS) uses two scanning infrared laser beams to illuminate retroreflectors located on aircraft landing gears and hook to determine very precisely the azimuthal, ascension, yaw, roll, and pitch angles of the aircraft in the approach corridor. The range, approach velocity, and aircraft type are also determined. Aircraft configuration is determined by the presence or absence of each return signal, and aircraft type is identified with an encoded sequence of retroreflectors on one landing gear. The position of the aircraft is determined by the time in the scan that the beam encounters the retroreflectors.

Vetter, Alan A.; Shemwell, David M.; Gellert, R. I.; Black, J.

1992-07-01

189

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

190

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

191

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

192

Biosignal alterations generated by parabolic flights of small aerobatic aircrafts  

NASA Astrophysics Data System (ADS)

Since the pioneering works of Prof. Strughold in 1948, the aerospace medicine aimed to characterize the modifications induced in the human body by changes in the gravity level. In this respect, it is nowadays well known that one of the most serious problems of these kind of environments is the fluid shift. If this effect is enough severe and persistent, serious changes in the hemodynamic of the brain (cerebral blood flow and blood oxigenation level) appear which could be detected as alterations in the electroencephalogram, EEG [1]. Also, this fluid redistribution, together with the relocation of the heart in the thorax, induces detectable changes in the electrocardiogram, ECG [2]. Other kind of important problems are related with vestibular instability, kinetosis and illusory sensations. In particular since the seventies [3,4] it is known that in parabolic flights and due to eye movements triggered by the changing input from the otholith system, fixed real targets appeared to have moved downward while visual afterimages appeared to have moved upward (oculogravic illusions). In order to cover all the above-mentioned potential alterations, the present work, together with the gravity level, continuously monitors the electroencephalogram, EEG, the electrocardiogram, ECG and the electrooculogram, EOG of a normal subject trying to detect correlations between the different alterations observed in these signals and the changes of gravity during parabolic flights. The small aerobatic aircraft used is a CAP10B and during the flight the subject is located near the pilot. To properly cover all the range of accelerations we have used two sensitive triaxial accelerometers covering the high and low ranges of acceleration. Biosignals have been gathered using a Biopac data unit together with the Acknowledge software package (from BionicÔ). It is important to finally remark that, due to the obvious difference between the power of the different engines, the accelerometric characteristics of the aerobatic parabolic flights are different from the ones corresponding to the big Airbus-300 of Novespace-CNES-ESA aircraft. In this case, the two episodes of hypergravity reach 1.8g for 3 seconds with 20-25 seconds of low gravity in between whereas the small aerobatic plane reaches 3g level during roughly 2.5 seconds and 8 seconds period of low gravity. This means that the present potential alterations of the human body are more aggressive but also faster. [1] Y. Kawai, M. Doi, A. Setogawa, R. Shimoyama, K. Ueda, Y. Asai, K. Tatebayashi, Effects of Microgravity on Cerebral Hemodynamics, Yonago Acta Medica, 46 (2003) 1-8. [2] E.A.I. Aidu, V.G. Trunov, L.I. Titomir, A. Capderou, P. Vaïda, Transformation of Vectorcardiogram Due to Gravitation Alteration, Measurement, Science Review, 3 (2003) 29-32. [3] R.J. Von Baumgarten, G. Baldrighi, G.L. Schillinger, O. Harth, R. Thuemler, Vestibular function in the space environment, Acta Astronautica, 2 (1975) 49-58. [4] http://reversiblefigures.blogspot.com.es/p/outreach.html

Simon, M. Jose; Perez-Poch, Antoni; Ruiz, Xavier; Gavalda, Fina; Saez, Nuria

193

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

194

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

195

NDE of Damage in Aircraft Flight Control Surfaces  

SciTech Connect

Flight control surfaces on an aircraft, such as ailerons, flaps, spoilers and rudders, are typically adhesively bonded composite or aluminum honeycomb sandwich structures. These components can suffer from damage caused by hail stone, runway debris, or dropped tools during maintenance. On composites, low velocity impact damages can escape visual inspection, whereas on aluminum honeycomb sandwich, budding failure of the honeycomb core may or may not be accompanied by a disbond. This paper reports a study of the damage morphology in such structures and the NDE methods for detecting and characterizing them. Impact damages or overload failures in composite sandwiches with Nomex or fiberglass core tend to be a fracture or crinkle or the honeycomb cell wall located a distance below the facesheet-to-core bondline. The damage in aluminum honeycomb is usually a buckling failure, propagating from the top skin downward. The NDE methods used in this work for mapping out these damages were: air-coupled ultrasonic scan, and imaging by computer aided tap tester. Representative results obtained from the field will be shown.

Hsu, David K.; Barnard, Daniel J.; Dayal, Vinay [Center for Nondestructive Evaluation, Iowa State University, Ames, IA 50011 (United States)

2007-03-21

196

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

197

Piracetam and fish orientation during parabolic aircraft flight  

NASA Technical Reports Server (NTRS)

Goldfish were flown in parabolic Keplerian trajectories in a KC-135 aircraft to assay both the effectiveness of piracetam as an antimotion sickness drug and the effectiveness of state-dependent training during periods of oscillating gravity levels. Single-frame analyses of infrared films were performed for two classes of responses - role rates in hypogravity or hypogravity orienting responses (LGR) and climbing responses in hypergravity or hypergravity orienting responses (HGR). In Experiment I, preflight training with the vestibular stressor facilitated suppression of LGR by the 10th parabola. An inverse correlation was found between the magnitudes of LGR and HGR. Piracetam was not effective in a state-dependent design, but the drug did significantly increase HGR when injected into trained fish shortly before flight. In Experiment II, injections of saline, piracetam, and modifiers of gamma-aminobutyric acid - aminooxyacetic acid (AOAA) and isonicotinic acid did not modify LGR. AOAA did significantly increase HGR. Thus, the preflight training has a beneficial effect in reducing disorientation in the fish in weightlessness, but the drugs employed were ineffective.

Hoffman, R. B.; Salinas, G. A.; Homick, J. L.

1980-01-01

198

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

199

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

NASA Technical Reports Server (NTRS)

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.; Mihelic, J. E.; Barnes, J. D.

1998-01-01

200

Modeling of Selected Aircraft Flight Phases Using Data from Flight Data Recorder  

NASA Astrophysics Data System (ADS)

While observing the dynamic air traffic increase, the issue of continuous controlling and monitoring every individual phase of flights becomes an essential matter. One of the phase of flight that has been studied is landing. At the commercial airports, landings take place every several dozen seconds up to few minutes. The correctness of carrying out required procedures has a crucial impact on the runway throughput, number of operations performed in the aerodrome vicinity and, above all, safety of the passengers. For obvious reasons the research and analysis of these processes cannot be done on objects in real conditions. Therefore, there is a tendency to use IT tools and other methods for the purpose of the analysis of the operations which take place in the aerodrome vicinity. In order to make use of the computer simulation it is essential to have mathematical models of these operations. The purpose of this article is to present methodology and defined a model that is based on parameters recorded by the flight data recorder. Models developed in that way map reality with high accuracy. Such models map the real aircraft operations in the aerodrome vicinity and can be applied in practice.

Stelmach, Anna

2012-02-01

201

Application of trajectory optimization techniques to upper atmosphere sampling flights using the F-15 Eagle aircraft  

NASA Technical Reports Server (NTRS)

Atmospheric sampling has been carried out by flights using an available high-performance supersonic aircraft. Altitude potential of an off-the-shelf F-15 aircraft is examined. It is shown that the standard F-15 has a maximum altitude capability in excess of 100,000 feet for routine flight operation by NASA personnel. 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.

1976-01-01

202

Design of a reconfigurable lateral flight control system for a C-135 aircraft  

E-print Network

DESIGN OF A RECONFIGURABLE LATERAL FLIGHT CONTROL SYSTEM FOR A C ? 135 AIRCRAFT A Thesis by COLIN ANDREW SWANEY Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE December 1990 Major Subject: Mechanical Engineering DESIGN OF A RECONFIGURABLE LATERA. L FLIGHT CONTROL SYSTEM FOR A C ? 135 AIRCRAFT A Thesis COLIN ANDREW SWANEY Approved as to style and content by: S. Jayasuriya (Chair...

Swaney, Colin Andrew

1990-01-01

203

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

204

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.

205

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

206

Flight Tests of the KO1 Aircraft at Night  

Microsoft Academic Search

The KO-1 aircraft which has the functionality of tactical observation, was successfully developed in August of 2004 in South Korea. It is important for the KO-1 aircraft to achieve successful missions at nighttime as well as during daytime. The aircraft, equipped with interior and exterior lighting systems and lighting control panel modified from those of the KT-1 basic trainer, provides

Jong-Kwang Kwon; Whan-Woo Kim

2007-01-01

207

Intercomparison of aircraft instruments on board the C-130 and Falcon 20 over southern Germany during EXPORT 2000  

NASA Astrophysics Data System (ADS)

In the summer 2000 Export aircraft campaign (European eXport of Precursors and Ozone by long-Range Transport), two comprehensively instrumented research aircraft measuring a variety of chemical species flew wing tip to wing tip for a period of one and a quarter hours. During this interval a comparison was undertaken of the measurements of nitrogen oxide (NO), odd nitrogen species (NOy), carbon monoxide (CO) and ozone (O3). The comparison was performed at two different flight levels, which provided a 10-fold variation in the concentrations of both NO (10 to 1000 parts per trillion by volume (pptv)) and NOy (200 to over 2500 pptv). Large peaks of NO and NOy observed from the Falcon 20, which were at first thought to be from the exhaust of the C-130, were also detected on the 4 channel NOx,y instrument aboard the C-130. These peaks were a good indication that both aircraft were in the same air mass and that the Falcon 20 was not in the exhaust plume of the C-130. Correlations and statistical analysis are presented between the instruments used on the two separate aircraft platforms. These were found to be in good agreement giving a high degree of correlation for the ambient air studied. Any deviations from the correlations are accounted for in the estimated inaccuracies of the instruments. These results help to establish that the instruments aboard the separate aircraft are reliably able to measure the corresponding chemical species in the range of conditions sampled and that data collected by both aircraft can be co-ordinated for purposes of interpretation.

Brough, N.; Reeves, C. E.; Penkett, S. A.; Dewey, K.; Kent, J.; Barjat, H.; Monks, P. S.; Ziereis, H.; Stock, P.; Huntrieser, H.; Schlager, H.

2003-07-01

208

Intercomparison of aircraft instruments on board the C-130 and Falcon 20 over southern Germany during EXPORT 2000  

NASA Astrophysics Data System (ADS)

In the summer 2000 EXPORT aircraft campaign (European eXport of Precursors and Ozone by long-Range Transport), two comprehensively instrumented research aircraft measuring a variety of chemical species flew wing tip to wing tip for a period of one and a quarter hours. During this interval a comparison was undertaken of the measurements of nitrogen oxide (NO), odd nitrogen species (NOy), carbon monoxide (CO) and ozone (O3). The comparison was performed at two different flight levels, which provided a 10-fold variation in the concentrations of both NO (10 to 1000 parts per trillion by volume (pptv)) and NOy (200 to over 2500 pptv). Large peaks of NO and NOy observed from the Falcon 20, which were at first thought to be from the exhaust of the C-130, were also detected on the 4 channel NOxy instrument aboard the C-130. These peaks were a good indication that both aircraft were in the same air mass and that the Falcon 20 was not in the exhaust plume of the C-130. Correlations and statistical analysis are presented between the instruments used on the two separate aircraft platforms. These were found to be in good agreement giving a high degree of correlation for the ambient air studied. Any deviations from the correlations are accounted for in the estimated inaccuracies of the instruments. These results help to establish that the instruments aboard the separate aircraft are reliably able to measure the corresponding chemical species in the range of conditions sampled and that data collected by both aircraft can be co-ordinated for purposes of interpretation.

Brough, N.; Reeves, C. E.; Penkett, S. A.; Stewart, D. J.; Dewey, K.; Kent, J.; Barjat, H.; Monks, P. S.; Ziereis, H.; Stock, P.; Huntrieser, H.; Schlager, H.

2003-12-01

209

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

210

An optical technique for examining aircraft shock wave structures in flight  

NASA Technical Reports Server (NTRS)

The detailed properties of sonic booms have to be better understood before commercial, next generation, supersonic and hypersonic aircraft can be properly developed. Experimental tests and measurements are needed to help sort the physical details of the flows at realistic test conditions. Some of these tests can be made in wind tunnels, but the need for full flight conditions simulation, the problem of tunnel wall interference, and the short distance the shocks can be examined from the aircraft, limit the usefulness of wind tunnel tests. Previous measurement techniques for examining the flow field of aircraft in flight have included pressure measurements on the aircraft, ground based pressure measurements, and flow field measurements made with chase aircraft. Obtaining data with chase planes is a slow and difficult process, and is limited in how close it can be obtained to the test aircraft. A need clearly existed for a better technique to examine the shock structure from the plane to large distances from the plane. A new technique has been recently developed to obtain schlieren photographs of aircraft in flight (SAF). Preliminary results have been obtained, and the technique holds promise as a tool to study the shape and approximate strength of the shock wave structure around the test aircraft, and examine shock wave details all the way from the aircraft to near the ground. The current paper describes this approach, and gives some preliminary test results.

Weinstein, Leonard M.

1994-01-01

211

Reduction environmental effects of civil aircraft through multi-objective flight plan optimisation  

NASA Astrophysics Data System (ADS)

With rising environmental alarm, the reduction of critical aircraft emissions including carbon dioxides (CO2) and nitrogen oxides (NOx) is one of most important aeronautical problems. There can be many possible attempts to solve such problem by designing new wing/aircraft shape, new efficient engine, etc. The paper rather provides a set of acceptable flight plans as a first step besides replacing current aircrafts. The paper investigates a green aircraft design optimisation in terms of aircraft range, mission fuel weight (CO2) and NOx using advanced Evolutionary Algorithms coupled to flight optimisation system software. Two multi-objective design optimisations are conducted to find the best set of flight plans for current aircrafts considering discretised altitude and Mach numbers without designing aircraft shape and engine types. The objectives of first optimisation are to maximise range of aircraft while minimising NOx with constant mission fuel weight. The second optimisation considers minimisation of mission fuel weight and NOx with fixed aircraft range. Numerical results show that the method is able to capture a set of useful trade-offs that reduce NOx and CO2 (minimum mission fuel weight).

Lee, D. S.; Gonzalez, L. F.; Walker, R.; Periaux, J.; Onate, E.

2010-06-01

212

Tunable diode laser in-situ CH4 measurements aboard the CARIBIC passenger aircraft: instrument performance assessment  

NASA Astrophysics Data System (ADS)

A laser spectrometer for automated monthly measurements of methane (CH4) mixing ratios aboard the CARIBIC passenger aircraft is presented. The instrument is based on a commercial Fast Greenhouse Gas Analyzer (FGGA, Los Gatos Res.), which was adapted to meet the requirements imposed by unattended airborne employment. The modified instrument is described. A laboratory characterization was performed to determine the instrument stability, precision, cross sensitivity to H2O, and accuracy. For airborne operation a calibration strategy is described, that utilizes CH4 measurements obtained from flask samples taken during the same flights. The precision of airborne measurements is 2 ppbv for 10 s averages. The accuracy at aircraft cruising altitude is 3.85 ppbv. During aircraft ascent and descent, where no flask samples were obtained, instrumental drifts can be less accurately considered and the uncertainty is estimated to be 12.4 ppbv. A linear humidity bias correction was applied to the CH4 measurements, which was most important in the lower troposphere. On average, the correction bias was around 6.5 ppbv at an altitude of 2 km, and negligible at cruising flight level. Observations from 103 long-distance flights are presented that span a large part of the northern hemispheric upper troposphere and lowermost stratosphere (UT/LMS), with occasional crossing of the tropics on flights to southern Africa. These accurate data mark the largest UT/LMS in-situ CH4 dataset worldwide. An example of a tracer-tracer correlation study with ozone is given, highlighting the possibility for accurate cross-tropopause transport analyses.

Dyroff, C.; Zahn, A.; Sanati, S.; Christner, E.; Rauthe-Schöch, A.; Schuck, T. J.

2013-10-01

213

Subminiaturization for ERAST instrumentation (Environmental Research Aircraft and Sensor Technology)  

NASA Technical Reports Server (NTRS)

We are focusing on the Argus as an example to demonstrate our philosophy on miniaturization of airborne analytical instruments for the study of atmospheric chemistry. Argus is a two channel, tunable-diode laser absorption spectrometer developed at NASA for the measurement of nitrogen dioxide (N2O) (4.5 micrometers) and ammonia (CH3) (3.3 micrometers) at the 0.1 parts per billion (ppb) level from the Perseus aircraft platform at altitudes up to 30 km. Although Argus' mass is down to 23 kg from the 197 kg Atlas, its predecessor, our goal is to design a next-generation subminiaturized instrument weighing less than 1 kg, measuring a few cm(exp 3) and able to eliminate dewars for cooling. Current designs enable use to make a small,inexpensive, monolithic spectrometer without the required sensitivity range. Further work is on its way to increase sensitivity. We are continuing to zero-base the technical approach in terms of the specifications for the given instrument. We are establishing a check list of questions to hone into the best micromachining approach and to superpose on the answers insights in scaling laws and flexible engineering designs to enable more relaxed tolerances for the smallest of the components.

Madou, Marc; Lowenstein, Max; Wegener, Steven

1995-01-01

214

Aircraft instrumentation system for the remote sensing of carbon monoxide  

NASA Technical Reports Server (NTRS)

A light twin-engine aircraft has been instrumented with a carbon monoxide remote gas sensor system and test flown over the Southern Lake Michigan basin during August, 1976. The remote sensor is based on the gas filter correlation technique. The radiance levels from the sensor along with the data on the surface temperature, air temperature, dewpoint, and altitude were digitized and recorded on seven-track magnetic tape. Air samples were collected at various altitudes over selected sites for later analysis of carbon monoxide concentration and comparison with the inferred concentration from the remote sensor. The values of carbon monoxide obtained from the air samples and the values inferred from the remote sensor for data collected over water are in good agreement.

Beck, S. M.; Hesketh, W. D.; Sherrill, R. T.

1978-01-01

215

Volume-imaging lidar observations of the convective structure surrounding the flight path of a flux-measuring aircraft  

NASA Technical Reports Server (NTRS)

The University of Wisconsin volume imaging lidar has been used to portray images of the three-dimensional structure of clear air convective plumes in the atmosphere surrounding the flight path of the instrumented Twin Otter aircraft operated by the National Aeronautical Establishment of Canada. Lidar images provide a context for interpretation of the aircraft measurements. The position of data points within a convective element can be determined and the temporal development of the plume can be observed to time the observation with respect to the life cycle of the plume. Plots of the vertical flux of water vapor, superimposed on lidar images clearly demonstrate the well-known sampling difficulties encountered when attempting to measure fluxes near the top of the convective layer. When loran was used to determine average aircraft velocity, flight-leg-averaged horizontal winds measured by the aircraft and area-averaged winds measured by lidar agree to within 0.2 m/s in speed and 1 deg in direction.

Eloranta, Edwin W.; Forrest, Daniel K.

1992-01-01

216

An integrated model for fleet routing, flight scheduling and aircraft rental planning  

Microsoft Academic Search

Fleet routing, flight scheduling and aircraft renting playa key role in airline carrier operations. This research rums at developmg a model to assist carriers in drafting flight timetables, providing better fleet routes, and making rental plans when market demand conditions are expected to change in the near future. The model is constructed as a time-space network and formulated as a

Shangyao Yan; Shwu-Ping Ho; Ta-Hui Yang

1997-01-01

217

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

218

Crew systems and flight station concepts for a 1995 transport aircraft  

NASA Technical Reports Server (NTRS)

Aircraft functional systems and crew systems were defined for a 1995 transport aircraft through a process of mission analysis, preliminary design, and evaluation in a soft mockup. This resulted in a revolutionary pilot's desk flight station design featuring an all-electric aircraft, fly-by-wire/light flight and thrust control systems, large electronic color head-down displays, head-up displays, touch panel controls for aircraft functional systems, voice command and response systems, and air traffic control systems projected for the 1990s. The conceptual aircraft, for which crew systems were designed, is a generic twin-engine wide-body, low-wing transport, capable of worldwide operation. The flight control system consists of conventional surfaces (some employed in unique ways) and new surfaces not used on current transports. The design will be incorporated into flight simulation facilities at NASA-Langley, NASA-Ames, and the Lockheed-Georgia Company. When interfaced with advanced air traffic control system models, the facilities will provide full-mission capability for researching issues affecting transport aircraft flight stations and crews of the 1990s.

Sexton, G. A.

1983-01-01

219

A Flight Study of the Conversion Maneuver of a Tilt-Duct VTOL Aircraft  

NASA Technical Reports Server (NTRS)

Flight records are presented from an early flight test of a wing-tip mounted tilting-ducted-fan, vertical-take-off and landing (VTOL) aircraft configuration. Time histories of the aircraft motions, control positions, and duct pitching-moment variation are presented to illustrate the characteristics of the aircraft in hovering, in conversion from hovering to forward flight, and in conversion from forward flight to hovering. The results indicate that during essentially continuous slow level- flight conversions, this aircraft experiences excessive longitudinal trim changes. Studies have shown that the large trim changes are caused primarily by the variation of aerodynamic moments acting on the duct units. Action of the duct-induced downwash on the horizontal stabilizer during the conversion also contributes to the longitudinal trim variations. Time histories of hovering and slow vertical descent in the final stages of landing in calm air show angular motions of the aircraft as great as +/- 10 deg. about all axes. Stick and pedal displacements required to control the aircraft during the landing maneuver were on the order of 50 to 60 percent of the total travel available.

Tapscott, Robert J.; Kelley, Henry L.

1960-01-01

220

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

221

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

222

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

223

Utilization of satellite imagery by in-flight aircraft. [for weather information  

NASA Technical Reports Server (NTRS)

Present and future utilization of satellite weather data by commercial aircraft while in flight was assessed. Weather information of interest to aviation that is available or will become available with future geostationary satellites includes the following: severe weather areas, jet stream location, weather observation at destination airport, fog areas, and vertical temperature profiles. Utilization of this information by in-flight aircraft is especially beneficial for flights over the oceans or over remote land areas where surface-based observations and communications are sparse and inadequate.

Luers, J. K.

1976-01-01

224

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

225

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

226

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

227

Tunable diode laser in-situ CH4 measurements aboard the CARIBIC passenger aircraft: instrument performance assessment  

NASA Astrophysics Data System (ADS)

A laser spectrometer for automated monthly measurements of methane (CH4) mixing ratios aboard the CARIBIC passenger aircraft is presented. The instrument is based on a commercial Fast Greenhouse Gas Analyser (FGGA, Los Gatos Res.), which was adapted to meet the requirements imposed by unattended airborne operation. It was characterised in the laboratory with respect to instrument stability, precision, cross sensitivity to H2O, and accuracy. For airborne operation, a calibration strategy is described that utilises CH4 measurements obtained from flask samples taken during the same flights. The precision of airborne measurements is 2 ppb for 10 s averages. The accuracy at aircraft cruising altitude is 3.85 ppb. During aircraft ascent and descent, where no flask samples were obtained, instrumental drifts can be less accurately determined and the uncertainty is estimated to be 12.4 ppb. A linear humidity bias correction was applied to the CH4 measurements, which was most important in the lower troposphere. On average, the correction bias was around 6.5 ppb at an altitude of 2 km, and negligible at cruising flight level. Observations from 103 long-distance flights are presented that span a large part of the northern hemispheric upper troposphere and lowermost stratosphere (UT/LMS), with occasional crossing of the tropics on flights to southern Africa. These accurate data mark the largest UT/LMS in-situ CH4 dataset worldwide. An example of a tracer-tracer correlation study with ozone is given, highlighting the possibility for accurate cross-tropopause transport analyses.

Dyroff, C.; Zahn, A.; Sanati, S.; Christner, E.; Rauthe-Schöch, A.; Schuck, T. J.

2014-03-01

228

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

229

Beyond the cockpit: The visual world as a flight instrument  

NASA Technical Reports Server (NTRS)

The use of cockpit instruments to guide flight control is not always an option (e.g., low level rotorcraft flight). Under such circumstances the pilot must use out-the-window information for control and navigation. Thus it is important to determine the basis of visually guided flight for several reasons: (1) to guide the design and construction of the visual displays used in training simulators; (2) to allow modeling of visibility restrictions brought about by weather, cockpit constraints, or distortions introduced by sensor systems; and (3) to aid in the development of displays that augment the cockpit window scene and are compatible with the pilot's visual extraction of information from the visual scene. The authors are actively pursuing these questions. We have on-going studies using both low-cost, lower fidelity flight simulators, and state-of-the-art helicopter simulation research facilities. Research results will be presented on: (1) the important visual scene information used in altitude and speed control; (2) the utility of monocular, stereo, and hyperstereo cues for the control of flight; (3) perceptual effects due to the differences between normal unaided daylight vision, and that made available by various night vision devices (e.g., light intensifying goggles and infra-red sensor displays); and (4) the utility of advanced contact displays in which instrument information is made part of the visual scene, as on a 'scene linked' head-up display (e.g., displaying altimeter information on a virtual billboard located on the ground).

Johnson, W. W.; Kaiser, M. K.; Foyle, D. C.

1992-01-01

230

Buffet induced structural/flight-control system interaction of the X-29A aircraft  

NASA Technical Reports Server (NTRS)

High angle-of-attack flight regime research is currently being conducted for modern fighter aircraft at the NASA Ames Research Center's Dryden Flight Research Facility. This flight regime provides enhanced maneuverability to fighter pilots in combat situations. Flight research data are being acquired to compare and validate advanced computational fluid dynamic solutions and wind-tunnel models. High angle-of-attack flight creates unique aerodynamic phenomena including wing rock and buffet on the airframe. These phenomena increase the level of excitation of the structural modes, especially on the vertical and horizontal stabilizers. With high gain digital flight-control systems, this structural response may result in an aeroservoelastic interaction. A structural interaction on the X-29A aircraft was observed during high angle-of-attack flight testing. The roll and yaw rate gyros sensed the aircraft's structural modes at 11, 13, and 16 Hz. The rate gyro output signals were then amplified through the flight-control laws and sent as commands to the flaperons and rudder. The flight data indicated that as the angle of attack increased, the amplitude of the buffet on the vertical stabilizer increased, which resulted in more excitation to the structural modes. The flight-control system sensors and command signals showed this increase in modal power at the structural frequencies up to a 30 degree angle-of-attack. Beyond a 30 degree angle-of-attack, the vertical stabilizer response, the feedback sensor amplitude, and control surface command signal amplitude remained relatively constant. Data are presented that show the increased modal power in the aircraft structural accelerometers, the feedback sensors, and the command signals as a function of angle of attack. This structural interaction is traced from the aerodynamic buffet to the flight-control surfaces.

Voracek, David F.; Clarke, Robert

1991-01-01

231

Instrumented personal exercise during long-duration space flights  

NASA Technical Reports Server (NTRS)

The present work reports the results of instrumented personal exercise performed in flight by Skylab 3 and 4 crewmen. Inflight cycle ergometer data provide conclusive evidence that man can perform earthbound equivalent maximum levels of physical work while in the zero-G environment. Moreover, SL4 crewmen were able to improve their physical condition during 84 days of space flight relative to launch condition, due to rigorous personal exercise regimens. Biological data measured included oxygen consumption, CO2 production, minute volume, and heart rate.

Sawin, C. F.; Rummel, J. A.; Michel, E. L.

1975-01-01

232

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

233

Developmental Flight Instrumentation System for the Crew Launch Vehicle  

NASA Technical Reports Server (NTRS)

The National Aeronautics and Space Administration is developing a new launch vehicle to replace the Space Shuttle. The Crew Launch Vehicle (CLV) will be a combination of new design hardware and heritage Apollo and Space Shuttle hardware. The current CLV configuration is a 5 segment solid rocket booster first stage and a new upper stage design with a modified Apollo era J-2 engine. The current schedule has two test flights with a first stage and a structurally identical, but without engine, upper stage. Then there will be two more test flights with a full complement of flight hardware. After the completion of the test flights, the first manned flight to the International Space Station is scheduled for late 2012. To verify the CLV's design margins a developmental flight instrumentation (DFI) system is needed. The DFI system will collect environmental and health data from the various CLV subsystem's and either transmit it to the ground or store it onboard for later evaluation on the ground. The CLV consists of 4 major elements: the first stage, the upper stage, the upper stage engine and the integration of the first stage, upper stage and upper stage engine. It is anticipated that each of CLVs elements will have some version of DFI. This paper will discuss a conceptual DFI design for each element and also of an integrated CLV DFI system.

Crawford, Kevin; Thomas, John

2006-01-01

234

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

235

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

236

Design of an intelligent flight instrumentation unit using embedded RTOS  

NASA Astrophysics Data System (ADS)

Micro Unmanned Aerial Vehicles (MUAV) must calculate its spatial position to control the flight dynamics, which is done by Inertial Measurement Units (IMUs). MEMS Inertial sensors have made possible to reduce the size and power consumption of such units. Commonly the flight instrumentation operates independently of the main processor. This work presents an instrumentation block design, which reduces size and power consumption of the complete system of a MUAV. This is done by coupling the inertial sensors to the main processor without considering any intermediate level of processing aside. Using Real Time Operating Systems (RTOS) reduces the number of intermediate components, increasing MUAV reliability. One advantage is the possibility to control several different sensors with a single communication bus. This feature of the MEMS sensors makes a smaller and less complex MUAV design possible.

Estrada-Marmolejo, R.; García-Torales, G.; Torres-Ortega, H. H.; Flores, J. L.

2011-09-01

237

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

238

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

239

Nonlinear vibration phenomenon of an aircraft rub-impact rotor system due to hovering flight  

NASA Astrophysics Data System (ADS)

This paper focuses on the nonlinear vibration phenomenon caused by aircraft hovering flight in a rub-impact rotor system supported by two general supports with cubic stiffness. The effect of aircraft hovering flight on the rotor system is considered as a maneuver load to formulate the equations of motion, which might result in periodic response instability to the rotor system even the eccentricity is small. The dynamic responses of the system under maneuver load are presented by bifurcation diagrams and the corresponding Lyapunov exponent spectrums. Numerical analyses are carried out to detect the periodic, sub-harmonic and quasi-periodic motions of the system, which are presented by orbit diagrams, phase trajectories, Poincare maps and amplitude power spectrums. The results obtained in this paper will contribute an understanding of the nonlinear dynamic behaviors of aircraft rotor systems in maneuvering flight.

Hou, Lei; Chen, Yushu; Cao, Qingjie

2014-01-01

240

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

241

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

242

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

243

Army-Navy Precipitation-Static Project: Part V-The High-Voltage Characteristics of Aircraft in Flight  

Microsoft Academic Search

The important high-voltage electrical characteristics of aircraft in flight are determined from (a) flight operations in precipitation areas; (b) flight operations using a new artificial charger to electrify the airplane in flight; (c) high-voltage experiments on the airplane supported in a giant hangar; and (d) theoretical analysis. It is shown how the fundamental electrical constants of the airplane may be

R. Gunn; J. P. Parker

1946-01-01

244

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

245

Aircraft ground vibration testing at NASA Ames-Dryden Flight Research Facility  

NASA Technical Reports Server (NTRS)

At the NASA Ames Research Center's Dryden Flight Research Facility at Edwards Air Force Base, California, a variety of ground vibration test techniques has been applied to an assortment of new or modified aerospace research vehicles. This paper presents a summary of these techniques and the experience gained from various applications. The role of ground vibration testing in the qualification of new and modified aircraft for flight is discussed. Data are presented for a wide variety of aircraft and component tests, including comparisons of sine-dwell, single-input random, and multiple-input random excitation methods on a JetStar airplane.

Kehoe, Michael W.

1987-01-01

246

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

247

Lockheed ER-2 #806 high altitude research aircraft in flight  

NASA Technical Reports Server (NTRS)

ER-2 tail number 806, 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 F-118 turbofan engine rated at 17,000 pounds thrust powers the ER-2.

1998-01-01

248

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 F-118 turbofan engine rated at 17,000 pounds thrust powers the ER-2.

1998-01-01

249

Lockheed ER-2 high altitude research aircraft in flight  

NASA Technical Reports Server (NTRS)

ER-2 tail number 706, 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 F-118 turbofan engine rated at 17,000 pounds thrust powers the ER-2.

1997-01-01

250

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

251

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

252

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

253

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

254

Operational Concept for Flight Crews to Participate in Merging and Spacing of Aircraft  

NASA Technical Reports Server (NTRS)

The predicted tripling of air traffic within the next 15 years is expected to cause significant aircraft delays and create a major financial burden for the airline industry unless the capacity of the National Airspace System can be increased. One approach to improve throughput and reduce delay is to develop new ground tools, airborne tools, and procedures to reduce the variance of aircraft delivery to the airport, thereby providing an increase in runway throughput capacity and a reduction in arrival aircraft delay. The first phase of the Merging and Spacing Concept employs a ground based tool used by Air Traffic Control that creates an arrival time to the runway threshold based on the aircraft s current position and speed, then makes minor adjustments to that schedule to accommodate runway throughput constraints such as weather and wake vortex separation criteria. The Merging and Spacing Concept also employs arrival routing that begins at an en route metering fix at altitude and continues to the runway threshold with defined lateral, vertical, and velocity criteria. This allows the desired spacing interval between aircraft at the runway to be translated back in time and space to the metering fix. The tool then calculates a specific speed for each aircraft to fly while enroute to the metering fix based on the adjusted land timing for that aircraft. This speed is data-linked to the crew who fly this speed, causing the aircraft to arrive at the metering fix with the assigned spacing interval behind the previous aircraft in the landing sequence. The second phase of the Merging and Spacing Concept increases the timing precision of the aircraft delivery to the runway threshold by having flight crews using an airborne system make minor speed changes during enroute, descent, and arrival phases of flight. These speed changes are based on broadcast aircraft state data to determine the difference between the actual and assigned time interval between the aircraft pair. The airborne software then calculates a speed adjustment to null that difference over the remaining flight trajectory. Follow-on phases still under development will expand the concept to all types of aircraft, arriving from any direction, merging at different fixes and altitudes, and to any airport. This paper describes the implementation phases of the Merging and Spacing Concept, and provides high-level results of research conducted to date.

Baxley, Brian T.; Barmore, Bryan E.; Abbott, Terence S.; Capron, William R.

2006-01-01

255

Production Support Flight Control Computers: Research Capability for F/A-18 Aircraft at Dryden Flight Research Center  

NASA Technical Reports Server (NTRS)

NASA Dryden Flight Research Center (DFRC) is working with the United States Navy to complete ground testing and initiate flight testing of a modified set of F/A-18 flight control computers. The Production Support Flight Control Computers (PSFCC) can give any fleet F/A-18 airplane an in-flight, pilot-selectable research control law capability. NASA DFRC can efficiently flight test the PSFCC for the following four reasons: (1) Six F/A-18 chase aircraft are available which could be used with the PSFCC; (2) An F/A-18 processor-in-the-loop simulation exists for validation testing; (3) The expertise has been developed in programming the research processor in the PSFCC; and (4) A well-defined process has been established for clearing flight control research projects for flight. This report presents a functional description of the PSFCC. Descriptions of the NASA DFRC facilities, PSFCC verification and validation process, and planned PSFCC projects are also provided.

Carter, John F.

1997-01-01

256

NASA rotor system research aircraft flight-test data report: Helicopter and compound configuration  

NASA Technical Reports Server (NTRS)

The flight test activities of the Rotor System Research Aircraft (RSRA), NASA 740, from June 30, 1981 to August 5, 1982 are reported. Tests were conducted in both the helicopter and compound configurations. Compound tests reconfirmed the Sikorsky flight envelope except that main rotor blade bending loads reached endurance at a speed about 10 knots lower than previously. Wing incidence changes were made from 0 to 10 deg.

Erickson, R. E.; Kufeld, R. M.; Cross, J. L.; Hodge, R. W.; Ericson, W. F.; Carter, R. D. G.

1984-01-01

257

Some vortical-flow flight experiments on slender aircraft that impacted the advancement of aeronautics  

Microsoft Academic Search

This paper highlights the three aerodynamic pillars of aeronautics; namely, theory\\/CFD, wind-tunnel experiments and flight tests, and notes that at any given time these three are not necessarily at the same level of maturity. After an initial history of these three pillars, the focus narrows to a brief history of some vortical-flow flight experiments on slender aircraft that have impacted

John E. Lamar

2009-01-01

258

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

259

The experimental determination of atmospheric absorption from aircraft acoustic flight tests  

NASA Technical Reports Server (NTRS)

A method for determining atmospheric absorption coefficients from acoustic flight test data is presented. Measurements from five series of acoustic flight tests were included in the study. The number of individual flights totaled 24: six Boeing 707 flights performed in May 1969 in connection with the turbofan nacelle modification program, eight flights from Boeing tests conducted during the same period, and 10 flights of the Boeing 747 airplane. The effects of errors in acoustic, meteorological, and aircraft performance and position measurements are discussed. Tabular data of the estimated sample variance of the data for each test are given for source directivity angles from 75 deg to 120 deg and each 1/3-octave frequency band. Graphic comparisons are made of absorption coefficients derived from ARP 866, using atmospheric profile data, with absorption coefficients determined by the experimental method described in the report.

Miller, R. L.; Oncley, P. B.

1971-01-01

260

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

261

Video Analysis of the Flight of a Model Aircraft  

ERIC Educational Resources Information Center

A video-analysis software tool has been employed in order to measure the steady-state values of the kinematics variables describing the longitudinal behaviour of a radio-controlled model aircraft during take-off, climbing and gliding. These experimental results have been compared with the theoretical steady-state configurations predicted by the…

Tarantino, Giovanni; Fazio, Claudio

2011-01-01

262

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.

263

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

264

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

265

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

266

Application of fiber Bragg grating sensors in light aircraft: ground and flight test  

NASA Astrophysics Data System (ADS)

Fiber optic sensors are being spotlighted as the means to monitoring aircraft conditions due to their excellent characteristics. This paper presents an affordable structural health monitoring system based on a fiber Bragg grating sensor (FBG) for application in light aircrafts. A total of 24 FBG sensors were installed in the main wing of the test bed aircraft. In the ground test, the intactness of the installed sensors and device operability were confirmed. During the flight test, the strain and temperature responses of the wing structure were measured by the on-board low-speed FBG interrogator. The measured strains were successfully converted into the flight load history through the load calibration coefficient obtained from the ground calibration test.

Kim, Jin-Hyuk; Shrestha, Pratik; Park, Yurim; Kim, Chun-Gon

2014-05-01

267

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

268

A study for active control research and validation using the Total In-Flight Simulator (TIFS) aircraft  

NASA Technical Reports Server (NTRS)

The results of a feasibility study and preliminary design for active control research and validation using the Total In-Flight Simulator (TIFS) aircraft are documented. Active control functions which can be demonstrated on the TIFS aircraft and the cost of preparing, equipping, and operating the TIFS aircraft for active control technology development are determined. It is shown that the TIFS aircraft is as a suitable test bed for inflight research and validation of many ACT concepts.

Chen, R. T. N.; Daughaday, H.; Andrisani, D., II; Till, R. D.; Weingarten, N. C.

1975-01-01

269

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

270

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

271

Parabolic flight experiments on physiological data acquisition and processing technologies using small jet aircraft (MU300).  

PubMed

The parabolic aircraft flight provides a short low gravity environment for approximately 20 seconds, which may not be sufficient for a research on the physiological phenomenon induced by actual weightlessness in space. However, the method is still useful to reveal essential and characteristic feature of physiological signs, and is available for testing hardware and also training of crew member during altered gravity. This paper reports the summary of parabolic flight experiments recently conducted as a NASDA program (1990-1992). The program is providing opportunities in low gravity research with small jet aircraft for researchers and agencies. The flight experiments in the life science area have been conducted mostly focused on a physiological changes and basic methodology which may be effective under the altered gravity condition. In this study, the following research team, NASDA, Research Institute of Environmental Medicine, Nagoya University, Toyohashi University of Technology, Tokyo Metropolitan Hospital, Torey Research Center and JSUP were involved and coordinated for the research. PMID:11538779

Watanabe, S; Nagaoka, S; Usui, S; Miyamoto, A; Suzuki, H; Hirata, T; Yoshimoto, S; Ueno, T; Kojima, T; Yamagata, M; Ishikura, S

1994-05-01

272

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

273

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

274

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

275

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

276

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

277

Ground and flight testing for aircraft guidance and control  

SciTech Connect

A simple airborne flight management descent algorithm designed to define a flight profile subject to the constraints of using idle thrust, a clean airplane configuration (landing gear up, flaps zero, and speed brakes retracted), and fixed-time end conditions was developed and flight tested in the NASA TSRV B-737 research airplane. The research test flights, conducted in the Denver ARTCC automated time-based metering LFM/PD ATC environment, demonstrated that time guidance and control in the cockpit was acceptable to the pilots and ATC controllers and resulted in arrival of the airplane over the metering fix with standard deviations in airspeed error of 6.5 knots, in altitude error of 23.7 m (77.8 ft), and in arrival time accuracy of 12 sec. These accuracies indicated a good representation of airplane performance and wind modeling. Fuel savings will be obtained on a fleet-wide basis through a reduction of the time error dispersions at the metering fix and on a single-airplane basis by presenting the pilot with guidance for a fuel-efficient descent.

Onken, R.; Rediess, H.A.

1984-12-01

278

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

279

An object-oriented, abductive interpreter for aircraft flight control  

E-print Network

. Abductive Inference PRELIMINARY WORK Eiffel. . Jet Simulation Project Interfaces. Executive . GUI. Pmgramming X Graphics. . . . . . . . . . . . . . . . Eiffel Graphic Library Bugs. Blackboard Interpmcess Communications BSD Unix Communication... Facilities. System V Unix Communication Facilities. X Event Queues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Membership Function Tool/Editor, FLIGHT MODE INTERPRETATION. . Decision Confidence Measure: Elementary...

Economides, Gregory Theo

1993-01-01

280

In-Flight Assessment of a Pursuit Guidance Display Format for Manually Flown Precision Instrument Approaches  

NASA Technical Reports Server (NTRS)

In-flight evaluations of a pursuit guidance display system for manually flown precision instrument approaches were performed. The guidance system was integrated into the RASCAL JUH-60A Black Hawk helicopter. The applicability of the pursuit guidance disp1aFs to the operation of Runway Independent Aircraft (RIA) is made evident because the displays allow the pilot to fly a complex, multi-segment, descending, decelerating approach trajectory. The complex trajectory chosen for this in-flight assessment began from a downwind abeam position at 110 knots and was hand-flown to a 50 ft decision altitude at 40 knots using a rate-command/attitude-hold plus turn-coordination control system. The elements of the pursuit guidance format displayed on a 10-inch liquid crystal display (LCD) flat panel consisted of a flightpath vector and a "leader" aircraft as the pursuit guidance element. Approach guidance was based primarily on carrier-phase differential Global Positioning System (GPS) navigation, and secondarily on both medium accuracy inertial navigation unit states and air data computer states. Required Navigation Performance (RNP) concepts were applied to the construction of display elements such as lateral/vertical deviation indicators and a tunnel that indicated to the pilot, in real-time, the performance with respect to RNP error bounds. The results of the flight evaluations of the guidance display show that precise path control for operating within tight RNP boundaries (RNP 0.007NM/24ft for initial approach, RNP 0.008NM/19ft for intermediate approach, and RNP 0.002NM/9ft for final approach) is attainable with minimal to moderate pilot workload.

Moralez, Ernesto, III; Tucker, George E.; Hindson, William S.; Frost, Chad R.; Hardy, Gordon H.

2004-01-01

281

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

282

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

283

Analysis of Control Strategies for Aircraft Flight Upset Recovery  

NASA Technical Reports Server (NTRS)

This paper proposes a framework for studying the ability of a control strategy, consisting of a control law and a command law, to recover an aircraft from ight conditions that may extend beyond the normal ight envelope. This study was carried out (i) by evaluating time responses of particular ight upsets, (ii) by evaluating local stability over an equilibrium manifold that included stall, and (iii) by bounding the set in the state space from where the vehicle can be safely own to wings-level ight. These states comprise what will be called the safely recoverable ight envelope (SRFE), which is a set containing the aircraft states from where a control strategy can safely stabilize the aircraft. By safe recovery it is implied that the tran- sient response stays between prescribed limits before converging to a steady horizontal ight. The calculation of the SRFE bounds yields the worst-case initial state corresponding to each control strategy. This information is used to compare alternative recovery strategies, determine their strengths and limitations, and identify the most e ective strategy. In regard to the control law, the authors developed feedback feedforward laws based on the gain scheduling of multivariable controllers. In regard to the command law, which is the mechanism governing the exogenous signals driving the feed- forward component of the controller, we developed laws with a feedback structure that combines local stability and transient response considera- tions. The upset recovery of the Generic Transport Model, a sub-scale twin-engine jet vehicle developed by NASA Langley Research Center, is used as a case study.

Crespo, Luis G.; Kenny, Sean P.; Cox, David E.; Muri, Daniel G.

2012-01-01

284

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

285

EOS Aqua AMSR-E Arctic Sea-Ice Validation Program: Arctic2006 Aircraft Campaign Flight Report  

NASA Technical Reports Server (NTRS)

In March 2006, a coordinated Arctic sea-ice validation field campaign using the NASA Wallops P-3B aircraft was successfully completed. This campaign was the second Alaskan Arctic field campaign for validating the Earth Observing System (EOS) Aqua Advanced Microwave Scanning Radiometer (AMSR-E) sea-ice products. The first campaign was completed in March 2003. The AMSR-E, designed and built by the Japanese Space 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. The focus of this campaign was on the validation of snow depth on sea ice and sea-ice temperature. This flight report describes the suite of instruments flown on the P-3, the objectives of each of the six flights, the Arctic regions overflown, and the coordination among satellite, aircraft, and surface-based measurements.

Cavalieri, D. J.; Markus, T.

2006-01-01

286

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

287

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

288

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

289

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

290

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

291

In-flight lift-drag characteristics for a forward-swept wing aircraft and comparisons with contemporary aircraft)  

NASA Technical Reports Server (NTRS)

Lift (L) and drag (D) characteristics have been obtained in flight for the X-29A airplane (a forward swept-wing demonstrator) for Mach numbers (M) from 0.4 to 1.3. Most of the data were obtained near an altitude of 30,000 ft. A representative Reynolds number for M = 0.9, and a pressure altitude of 30,000 ft, is 18.6 x 10(exp 6) based on the mean aerodynamic chord. The X-29A data (forward-swept wing) are compared with three high-performance fighter aircraft: the F-15C, F-16C, and F/A18. The lifting efficiency of the X-29A, as defined by the Oswald lifting efficiency factor, e, is about average for a cantilevered monoplane for M = 0.6 and angles of attack up to those required for maximum L/D. At M = 0.6 the level of L/D and e, as a function of load factor, for the X-29A was about the same as for the contemporary aircraft. The X-29A and its contemporaries have high transonic wave drag and equivalent parasite area compared with aircraft of the 1940's through 1960's.

Saltzman, Edwin J.; Hicks, John W.; Luke, Sue (editor)

1994-01-01

292

Salmonellosis outbreak on transatlantic flights; foodborne illness on aircraft: 1947-1984.  

PubMed

In March 1984, 186 cases of gastroenteritis due to Salmonella enteritidis were reported after 29 flights to the United States on an international airline. An estimated 2,747 passengers on flights to the United States were affected. Illness was associated with flying supersonic or first class (odds ratio = 15, p less than 0.001). Eating food from the first-class menu was associated with illness (p = 0.09), and eating a tourist-class entree was protective (p less than 0.01). In 23 reported outbreaks of foodborne illness on aircraft, Salmonella has been the most common pathogen (seven outbreaks), followed by Staphylococcus (five outbreaks), and Vibrio species (five outbreaks). Outbreaks are most often the result of an improper temperature for preparation or for holding food in the flight kitchens. Serving the flight crew meals from one kitchen carries the risk that the entire crew will become ill. PMID:3788944

Tauxe, R V; Tormey, M P; Mascola, L; Hargrett-Bean, N T; Blake, P A

1987-01-01

293

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

294

Interactive aircraft flight control and aeroelastic stabilization. [forward swept wing flight vehicles  

NASA Technical Reports Server (NTRS)

Several examples are presented in which flutter involving interaction between flight mechanics modes and elastic wind bending occurs for a forward swept wing flight vehicle. These results show the basic mechanism by which the instability occurs and form the basis for attempts to actively control such a vehicle.

Weisshaar, T. A.; Schmidt, D. K.

1981-01-01

295

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

296

On the problem of large perturbation flow created by near-hovering flight of aircraft  

E-print Network

Resultant force "H" force F F FH Wang force "H" force for which G'& O "H" force for wnich G & C3 'H" for. e for which Q= O The set vf points oocupieti by the configuration Total presents Total. pressure in ultimate wake The c ass of helicopters... of change of momentum caused by flow deflection in fast flight. The typical aircraft struoture producing flow deflection snd foroe F? ie the fixed wing, although the autogiro and helicopter rotors in fast flight behave substantially like fixed wings...

Rudderow, William Henry

1960-01-01

297

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

298

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

299

In-Flight Alignment Using H? Filter for Strapdown INS on Aircraft  

PubMed Central

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

300

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

301

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

302

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

303

Flight dynamics simulation modeling and control of a large flexible tiltrotor aircraft  

NASA Astrophysics Data System (ADS)

A high order rotorcraft mathematical model is developed and validated against the XV-15 and a Large Civil Tiltrotor (LCTR) concept. The mathematical model is generic and allows for any rotorcraft configuration, from single main rotor helicopters to coaxial and tiltrotor aircraft. Rigid-body and inflow states, as well as flexible wing and blade states are used in the analysis. The separate modeling of each rotorcraft component allows for structural flexibility to be included, which is important when modeling large aircraft where structural modes affect the flight dynamics frequency ranges of interest, generally 1 to 20 rad/sec. Details of the formulation of the mathematical model are given, including derivations of structural, aerodynamic, and inertial loads. The linking of the components of the aircraft is developed using an approach similar to multibody analyses by exploiting a tree topology, but without equations of constraints. Assessments of the effects of wing flexibility are given. Flexibility effects are evaluated by looking at the nature of the couplings between rigid-body modes and wing structural modes and vice versa. The effects of various different forms of structural feedback on aircraft dynamics are analyzed. A proportional-integral feedback on the structural acceleration is deemed to be most effective at both improving the damping and reducing the overall excitation of a structural mode. A model following control architecture is then implemented on full order flexible LCTR models. For this aircraft, the four lowest frequency structural modes are below 20 rad/sec, and are thus needed for control law development and analysis. The impact of structural feedback on both Attitude-Command, Attitude-Hold (ACAH) and Translational Rate Command (TRC) response types are investigated. A rigid aircraft model has optimistic performance characteristics, and a control system designed for a rigid aircraft could potentially destabilize a flexible one. The various control systems are flown in a fixed-base simulator. Pilot inputs and aircraft performance are recorded and analyzed.

Juhasz, Ondrej

304

Adaptation of an In Situ Ground-Based Tropospheric OH/HO2 Instrument for Aircraft Use  

NASA Technical Reports Server (NTRS)

In-situ HO(x) (OH and HO2) measurements are an essential part of understanding the photochemistry of aircraft exhaust in the atmosphere. HO(x) affects the partitioning of nitrogen species in the NO(y) family. Its reactions are important sources and sinks for tropospheric ozone, thus providing a link between the NO(x) in aircraft exhaust and tropospheric ozone. OH mixing ratios are enhanced in aircraft wakes due to the photolysis of the HONO that is made close to the engine. Measurements of HO(x) in aircraft wakes, along with NO(x) measurements, thus provides a constraint on chemical models of the engine combustion and exhaust. The development of the Airborne Tropospheric Hydrogen Oxides Sensor (ATHOS) is reported. We designed, developed, and successfully flew this instrument. It was part of the instrument complement on board the NASA DC-8 during SUCCESS, which took place in Kansas in April and May, 1996. ATHOS has a limit-of-detection for OH (S/N = 2) of 10(exp 5) OH molecules cm(exp -3) in less than 150 seconds. While this sensitivity is about 2-3 times less than the initial projections in the proposal, it is more than adequate for good measurements of OH and HO2 from the planetary boundary layer to the stratosphere. Our participation in SUCCESS was to be engineering test flights for ATHOS; however, the high-quality measurements we obtained are being used to study HO(x) photochemistry in contrails, clouds, and the clear air.

Brune, William H.

1997-01-01

305

A wake bending unsteady dynamic inflow model of tiltrotor in conversion flight of tiltrotor aircraft  

Microsoft Academic Search

The aerodynamics, dynamic responses and aeroelasticity of tiltrotor aircraft in the tilting of rotor i.e. in conversion flight\\u000a are extraordinarily complicated. The traditional quasi-steady assumption model can not reflect the unsteady aerodynamic problems\\u000a in the tilting of rotor. The CFD method based on the vortex theory can get better results, but it consumes a lot of computing\\u000a resources. In this

HaiLong Yue; PinQi Xia

2009-01-01

306

V/STOL tilt rotor aircraft study. Volume 7: Tilt rotor flight control program feedback studies  

NASA Technical Reports Server (NTRS)

An exploratory study has been made of the use of feedback control in tilt rotor aircraft. This has included the use of swashplate cyclic and collective controls and direct lift control. Various sensor and feedback systems are evaluated in relation to blade loads alleviation, improvement in flying qualities, and modal suppression. Recommendations are made regarding additional analytical and wind tunnel investigations and development of feedback systems in the full scale flight vehicle. Estimated costs and schedules are given.

Alexander, H. R.; Eason, W.; Gillmore, K.; Morris, J.; Spittle, R.

1973-01-01

307

Criteria for design of 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 U.S./U.K. STOVL Joint Assessment and Ranking Team. The control system designs have been evaluated throughout the powered-lift flight envelope on the Vertical Motion Simulator (VMS) at Ames Research Center. 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

308

Aircraft Fuel Savings in Jet Streams by Maximising Features of Flight Mechanics and Navigation  

NASA Astrophysics Data System (ADS)

Performance enhancement and cost reduction are driving forces in today's airline industry. In a world of cost pressures and escalating charges, research was conducted into better use of jet streams as a means of reducing costs. When operating on international airline routes, specific features of flight mechanics were adapted and tailored to fit a B747-200 aircraft, major emphasis being placed on intercepting, or avoiding where necessary, the high energy jet stream winds of the global weather system, adjusting flight profiles and modifying route structures. Operations were conducted both into wind and down wind, over a period of five years. Techniques employed show fuel may be saved regardless of the wind being a tailwind or headwind. Both fuel and time have a significant bearing on airline direct operating costs: savings of more than 1·1 percent being made on fuel and 0·786 percent on time. Limitations on using the techniques to gain maximum benefit are related to the high volume of aircraft blocking all major airways, and better quality, real time weather forecasts. The discussion looks at ways of improving the use of jet streams, as the world's airline traffic continues to grow. Forecasting upper winds, particularly in oceanic areas, needs to improve if airlines are to derive maximum benefits from these winds. There is need for further study utilising other aircraft types to ascertain what savings can result. Initial results were encouraging, using a Tristar L1011 aircraft.

Houghton, Ronald C. C.

1998-09-01

309

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

310

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

311

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

312

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

313

Tiltrotor noise reduction through flight trajectory management and aircraft configuration control  

NASA Astrophysics Data System (ADS)

A tiltrotor can hover, takeoff and land vertically as well as cruise at high speeds and fly long distances. Because of these unique capabilities, tiltrotors are envisioned as an aircraft that could provide a solution to the issue of airport gridlock by operating on stub runways, helipads, or from smaller regional airports. However, during an approach-to-land a tiltrotor is susceptible to radiating strong impulsive noise, in particular, Blade-Vortex Interaction noise (BVI), a phenomenon highly dependent on the vehicle's performance-state. A mathematical model was developed to predict the quasi-static performance characteristics of a tiltrotor during a converting approach in the longitudinal plane. Additionally, a neural network was designed to model the acoustic results from a flight test of the XV-15 tiltrotor as a function of the aircraft's performance parameters. The performance model was linked to the neural network to yield a combined performance/acoustic model that is capable of predicting tiltrotor noise emitted during a decelerating approach. The model was then used to study noise trends associated with different combinations of airspeed, nacelle tilt, and flight path angle. It showed that BVI noise is the dominant noise source during a descent and that its strength increases with steeper descent angles. Strong BVI noise was observed at very steep flight path angles, suggesting that the tiltrotor's high downwash prevents the wake from being pushed above the rotor, even at such steep descent angles. The model was used to study the effects of various aircraft configuration and flight trajectory parameters on the rotor inflow, which adequately captured the measured BVI noise trends. Flight path management effectively constrained the rotor inflow during a converting approach and thus limited the strength of BVI noise. The maximum deceleration was also constrained by controlling the nacelle tilt-rate during conversion. By applying these constraints, low BVI noise approaches that take into account the first-order effects of deceleration on the acoustics were systematically designed and compared to a baseline approach profile. The low-noise approaches yielded substantial noise reduction benefits on a hemisphere surrounding the aircraft and on a ground plane below the aircraft's trajectory.

Gervais, Marc

314

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

315

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

316

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

317

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

318

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

319

Design Considerations for a Launch Vehicle Development Flight Instrumentation System  

NASA Technical Reports Server (NTRS)

When embarking into the design of a new launch vehicle, engineering models of expected vehicle performance are always generated. While many models are well established and understood, some models contain design features that are only marginally known. Unfortunately, these analytical models produce uncertainties in design margins. The best way to answer these analytical issues is with vehicle level testing. The National Aeronautics and Space Administration respond to these uncertainties by using a vehicle level system called the Development Flight Instrumentation, or DFI. This DFI system can be simple to implement, with only a few measurements, or it may be a sophisticated system with hundreds of measurement and video, without a recording capability. From experience with DFI systems, DFI never goes away. The system is renamed and allowed to continue, in most cases. Proper system design can aid the transition to future data requirements. This paper will discuss design features that need to be considered when developing a DFI system for a launch vehicle. It will briefly review the data acquisition units, sensors, multiplexers and recorders, telemetry components and harnessing. It will present a reasonable set of requirements which should be implemented in the beginning of the program in order to start the design. It will discuss a simplistic DFI architecture that could be the basis for the next NASA launch vehicle. This will be followed by a discussion of the "experiences gained" from a past DFI system implementation, such as the very successful Ares I-X test flight. Application of these design considerations may not work for every situation, but they may direct a path toward success or at least make one pause and ask the right questions.

Johnson, Martin L.; Crawford, Kevin

2011-01-01

320

Evaluation of cloud detection instruments and performance of laminar-flow leading-edge test articles during NASA Leading-Edge Flight-Test Program  

NASA Technical Reports Server (NTRS)

Summary evaluations of the performance of laminar-flow control (LFC) leading edge test articles on a NASA JetStar aircraft are presented. Statistics, presented for the test articles' performance in haze and cloud situations, as well as in clear air, show a significant effect of cloud particle concentrations on the extent of laminar flow. The cloud particle environment was monitored by two instruments, a cloud particle spectrometer (Knollenberg probe) and a charging patch. Both instruments are evaluated as diagnostic aids for avoiding laminar-flow detrimental particle concentrations in future LFC aircraft operations. The data base covers 19 flights in the simulated airline service phase of the NASA Leading-Edge Flight-Test (LEFT) Program.

Davis, Richard E.; Maddalon, Dal V.; Wagner, Richard D.; Fisher, David F.; Young, Ronald

1989-01-01

321

Instrumentation requirements for aircraft parameter identification with application to the helicopter  

NASA Technical Reports Server (NTRS)

The extent to which instrumentation errors cause degradation in the knowledge of stability and control derivatives identified for flight tests was studied along with the resultant degradation of the flight system performance base on these derivatives. The error in measurement and data processing systems used for parameter identification, error analysis techniques, and the effects of instrumentation, errors on the accuracy of parameter estimates are discussed. The analysis programs were used to study instrumentation error effects on the accuracy of the identified stability and control derivatives of the CH-46 helicopter.

Sorensen, J. A.; Mohr, R. L.; Cline, T. B.

1975-01-01

322

Development and application of linear and nonlinear methods for interpretation of lightning strikes to in-flight aircraft  

NASA Technical Reports Server (NTRS)

Since 1980, NASA has been collecting direct strike lightning data by flying an instrumented F-106B aircraft into thunderstorms. The continuing effort to interpret the measured data is reported here. Both linear and nonlinear finite difference modeling techniques are applied to the problem of lightning triggered by an aircraft in a thunderstorm. Five different aircraft are analyzed to determine the effect of aircraft size and shape on lightning triggering. The effect of lightning channel impedance on aircraft response is investigated. The particle environment in thunderstorms and electric field enhancements by typical ice particles is also investigated.

Rudolph, Terence; Perala, Rodney A.; Easterbrook, Calvin C.; Parker, Steven L.

1986-01-01

323

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

324

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

325

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

Code of Federal Regulations, 2014 CFR

...TRAFFIC AND GENERAL OPERATING RULES GENERAL OPERATING AND FLIGHT RULES...unless the aircraft is operating under part 121 of this...16) For normal, utility, and acrobatic category...adequate source of electrical energy for all...

2014-01-01

326

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

Code of Federal Regulations, 2013 CFR

...TRAFFIC AND GENERAL OPERATING RULES GENERAL OPERATING AND FLIGHT RULES...unless the aircraft is operating under part 121 of this...16) For normal, utility, and acrobatic category...adequate source of electrical energy for all...

2013-01-01

327

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

Code of Federal Regulations, 2012 CFR

...TRAFFIC AND GENERAL OPERATING RULES GENERAL OPERATING AND FLIGHT RULES...unless the aircraft is operating under part 121 of this...16) For normal, utility, and acrobatic category...adequate source of electrical energy for all...

2012-01-01

328

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

Code of Federal Regulations, 2011 CFR

...TRAFFIC AND GENERAL OPERATING RULES GENERAL OPERATING AND FLIGHT RULES...unless the aircraft is operating under part 121 of this...16) For normal, utility, and acrobatic category...adequate source of electrical energy for all...

2011-01-01

329

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

330

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

331

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

332

Ground Vibration and Flight Flutter Tests of the Single-seat F-16XL Aircraft with a Modified Wing  

NASA Technical Reports Server (NTRS)

The NASA single-seat F-16XL aircraft was modified by the addition of a glove to the left wing. Vibration tests were conducted on the ground to assess the changes to the aircraft caused by the glove. Flight Luther testing was conducted on the aircraft with the glove installed to ensure that the flight envelope was free of aeroelastic or aeroservoelastic instabilities. The ground vibration tests showed that above 20 Hz, several modes that involved the control surfaces were significantly changed. Flight test data showed that modal damping levels and trends were satisfactory where obtainable. The data presented in this report include estimated modal parameters from the ground vibration and flight flutter test.

Voracek, David F.

1993-01-01

333

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

334

Flight Test of an Adaptive Configuration Optimization System for Transport Aircraft  

NASA Technical Reports Server (NTRS)

A NASA Dryden Flight Research Center program explores the practical application of real-time adaptive configuration optimization for enhanced transport performance on an L-1011 aircraft. This approach is based on calculation of incremental drag from forced-response, symmetric, outboard aileron maneuvers. In real-time operation, the symmetric outboard aileron deflection is directly optimized, and the horizontal stabilator and angle of attack are indirectly optimized. A flight experiment has been conducted from an onboard research engineering test station, and flight research results are presented herein. The optimization system has demonstrated the capability of determining the minimum drag configuration of the aircraft in real time. The drag-minimization algorithm is capable of identifying drag to approximately a one-drag-count level. Optimizing the symmetric outboard aileron position realizes a drag reduction of 2-3 drag counts (approximately 1 percent). Algorithm analysis of maneuvers indicate that two-sided raised-cosine maneuvers improve definition of the symmetric outboard aileron drag effect, thereby improving analysis results and consistency. Ramp maneuvers provide a more even distribution of data collection as a function of excitation deflection than raised-cosine maneuvers provide. A commercial operational system would require airdata calculations and normal output of current inertial navigation systems; engine pressure ratio measurements would be optional.

Gilyard, Glenn B.; Georgie, Jennifer; Barnicki, Joseph S.

1999-01-01

335

Airborne prototype instrument suite test flight of a low-light high-dynamic range imager and visible spectrometer  

NASA Astrophysics Data System (ADS)

The Airborne Sensors Initiative (ASI) at Ball Aerospace and Technologies Corp. (BATC) specializes in airborne demonstration of internally-developed instrument concepts and innovative remote sensing technologies. In December 2006, ASI flew an environmental remote sensing suite consisting of the Low Light Imager (LLI) and Prototype Airborne Visible Imaging Spectrometer (PAVIS), both of which are operated using a pushbroom approach. LLI is designed for nighttime or high dynamic range imaging. It is capable of yielding 10 7 dynamic range and offers quality images amid illumination extending from a 1/ 4 moon to full sunlight and with autonomous operation. PAVIS is an imaging spectrometer based on the Dyson design and exhibits a 200 nm spectral bandwidth tunable within 400 - 850 nm. Developed internally to demonstrate promising remote sensing capabilities, these small, low-mass and low-power instruments are prepared for aircraft flight and are currently being used in the field to acquire scientific data. The LLI/PAVIS instrument suite has been utilized to collect airborne urban and rural imagery, as well as spectral information about the Great Salt Lake area, western Colorado, and ancient lava flows in southern Idaho. Highlights of the instrument design and ensuing data from previous flights are presented herein.

Kuester, Michele A.; Lasnik, James K.; Ramond, Tanya; Lin, Tony; Johnson, Brian; Kaptchen, Paul; Good, William

2007-09-01

336

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

337

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

338

Flight Crew Sleep in Long-Haul Aircraft Bunk Facilities: Survey Results  

NASA Technical Reports Server (NTRS)

Modem long-haul aircraft can fly up to 16 continuous hours and provide a 24-hour, global capability. Extra (augmented) flight crew are available on long flights to allow planned rest periods, on a rotating basis, away from the flight deck in onboard crew rest facilities (2 bunks). A NASA/FAA study is under-way to examine the quantity and quality of sleep obtained in long-haul aircraft bunks and the factors that promote or interfere with that sleep. The first phase of the study involved a retrospective survey, followed by a second phase field study to collect standard polysomnographic data during inflight bunk sleep periods. A summary of the Phase I survey results are reported here. A multi-part 54-question retrospective survey was completed by 1,404 flight crew (37% return rate) at three different major US air carriers flying B747-100, 200, 400, and MD- 11 long-haul aircraft. The questions examined demographics, quantity and quality of sleep at home and in onboard bunks, factors that promote or interfere with sleep, and effects on subsequent performance and alertness. Flight crew reported a mean bunk sleep latency of 39.4 mins (SD=28.3 mins) (n=1,276) and a mean total sleep time of 2.2 hrs (SD=1.3 hrs) (n=603). (Different flight lengths could affect overall time available for sleep.) Crew rated 25 factors for their interference or promotion of bunk sleep. Figure I portrays the average ratings for each factor across all three carriers. A principal components analysis of the 25 factors revealed three areas that promoted bunk sleep: physiological (e.g., readiness for sleep), physical environment (e.g., bunk size, privacy), and personal comfort (e.g., blankets, pillows). Five areas were identified that interfered with sleep: environmental disturbance (e.g., background noise, turbulence), luminosity (e.g., lighting), personal disturbances (e.g., bathroom trips, random thoughts), environmental discomfort (e.g., low humidity, cold), and interpersonal disturbances (e.g., bunk partner).

Rosekind, Mark R.; Miller, Donna L.; Gregory, Kevin B.; Dinges, David F.; Shafto, Michael G. (Technical Monitor)

1995-01-01

339

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

340

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

NASA Technical Reports Server (NTRS)

Kevlar-49 fairing panels were inspected and found to be performing satisfactorily after two years flight service on an Eastern and an Air Canada L-1011. Six panels are on each aircraft including sandwich and solid laminate wing-body panels, and 300 F service aft engine fairings. Some of the panels were removed from the aircraft to permit inspection of inner surfaces and fastener hole conditions. Minor defects such as surface cracks due to impact damage, small delaminated areas, elongation and fraying of fastener holes, were noted. None of these defects were considered serious enough to warrant corrective action in the opinion of airline personnel. The defects are typical for the most part of defects noted on similar fiberglass parts.

Stone, R. H.

1975-01-01

341

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

342

A Heading and Flight-Path Angle Control of Aircraft Based on Required Acceleration Vector  

NASA Astrophysics Data System (ADS)

This paper describes a control of heading and flight-path angles of aircraft to time-varying command angles. The controller first calculates an acceleration command vector (acV), which is vertical to the velocity vector. acV consists of two components; the one is feedforward acceleration obtained from the rates of command angles, and the other is feedback acceleration obtained from angle deviations by using PID control law. A bank angle command around the velocity vector and commands of pitch and yaw rates are then obtained to generate the required acceleration. A roll rate command is calculated from bank angle deviation. Roll, pitch and yaw rate commands are put into the attitude controller, which can be composed of any suitable control laws such as PID control. The control requires neither aerodynamic coefficients nor online calculation of the inverse dynamics of the aircraft. A numerical simulation illustrates the effects of the control.

Yoshitani, Naoharu

343

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

344

The Development of Instrumentation and Methods for Measurement of Air-Sea Interaction and Coastal Processes from Manned and Unmanned Aircraft  

NASA Astrophysics Data System (ADS)

I present the development of instrumentation and methods for the measurement of coastal processes, ocean surface phenomena, and air-sea interaction in two parts. In the first, I discuss the development of a portable scanning lidar (light detection and ranging) system for manned aircraft and demonstrate its functionality for oceanographic and coastal measurements. Measurements of the Southern California coastline and nearshore surface wave fields from seventeen research flights between August 2007 and December 2008 are analyzed and discussed. The October 2007 landslide on Mt. Soledad in La Jolla, California was documented by two of the flights. The topography, lagoon, reef, and surrounding wave field of Lady Elliot Island in Australia's Great Barrier Reef were measured with the airborne scanning lidar system on eight research flights in April 2008. Applications of the system, including coastal topographic surveys, wave measurements, ship wake studies, and coral reef research, are presented and discussed. In the second part, I detail the development of instrumentation packages for small (18 -- 28 kg) unmanned aerial vehicles (UAVs) to measure momentum fluxes and latent, sensible, and radiative heat fluxes in the atmospheric boundary layer (ABL), and the surface topography. Fast-response turbulence, hygrometer, and temperature probes permit turbulent momentum and heat flux measurements, and short- and long-wave radiometers allow the determination of net radiation, surface temperature, and albedo. Careful design and testing of an accurate turbulence probe, as demonstrated in this thesis, are essential for the ability to measure momentum and scalar fluxes. The low altitude required for accurate flux measurements (typically assumed to be 30 m) is below the typical safety limit of manned research aircraft; however, it is now within the capability of small UAV platforms. Flight tests of two instrumented BAE Manta UAVs over land were conducted in January 2011 at McMillan Airfield (Camp Roberts, CA), and flight tests of similarly instrumented Boeing-Insitu ScanEagle UAVs were conducted in April 2012 at the Naval Surface Warfare Center, Dahlgren Division (Dahlgren, VA), where the first known direct flux measurements were made from low-altitude (down to 30 m) UAV flights over water (Potomac River). During the October 2012 Equatorial Mixing Experiment in the central Pacific aboard the R/V Roger Revelle, ship-launched and recovered ScanEagles were deployed in an effort to characterize the marine atmospheric boundary layer structure and dynamics. I present a description of the instrumentation, summarize results from flight tests, present preliminary analysis from UAV flights off of the Revelle, and discuss potential applications of these UAVs for marine atmospheric boundary layer studies.

Reineman, Benjamin D.

345

Hazards to people and aircraft from flight test debris generated at high altitudes  

SciTech Connect

One of the most important aspects of preparing for a rocket-boosted flight test is conducting a mission hazards analysis to quantify the risks associated with the test. These results must be presented to the organization holding the flight safety responsibility for the test and must be of sufficient quantitative detail and thoroughness to show that the test can be conducted within the specified safety guidelines. One of the steps in the flight safety analysis methodology is the generation of statistical debris density data, which is then combined with demographic data to yield an upper bound on the casualty expectation. The most conservative approach to managing the hazards associated with flight-test debris is to contain all debris within a controlled area and keep all nonessential personnel out of that area. However, for many tests this approach is much too conservative. A more realistic approach, especially when large numbers of small fragments are generated, is to reduce the size of the hazard area by discarding those debris fragments that are non-hazardous. The quantification of the boundary between hazardous and non-hazardous debris fragments is the subject of this report. Two hazards of flight-test debris are address here: hazards to people exposed on the ground and hazards to aircraft in flight. A survey was conducted of the literature and of experts in the field of debris effects. The survey results are presented here and recommendations made regarding the minimum energy levels and minimum particle size that need be considered in a flight safety analysis.

Cole, J.K.; Wolfe, W.P. [Sandia National Labs., Albuquerque, NM (United States). Flight Dynamics Dept.

1994-08-01

346

Aircraft motion and passenger comfort data from scheduled commercial airline flights  

NASA Technical Reports Server (NTRS)

Data concerning the ride quality of aircraft taken on board commercial airline flights was presented. Five types of data are included: (1) root mean square (RMS) values of linear acceleration, angular acceleration or angular velocities, along with passenger subjective evaluations, (2) power spectra for the motion in each of six degrees of freedom, (3) scattergrams showing the probability density of the rms accelerations in the vertical and transverse directions, (4) probability distributions of the motion, and (5) on board noise levels during takeoff, climb, cruise, and descent.

Gruesbeck, M. G.; Sullivan, D. F.

1976-01-01

347

Redundant actuator development study. [flight control systems for supersonic transport aircraft  

NASA Technical Reports Server (NTRS)

Current and past supersonic transport configurations are reviewed to assess redundancy requirements for future airplane control systems. Secondary actuators used in stability augmentation systems will probably be the most critical actuator application and require the highest level of redundancy. Two methods of actuator redundancy mechanization have been recommended for further study. Math models of the recommended systems have been developed for use in future computer simulations. A long range plan has been formulated for actuator hardware development and testing in conjunction with the NASA Flight Simulator for Advanced Aircraft.

Ryder, D. R.

1973-01-01

348

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

349

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

350

Effect of combined roll rate and sideslip angle on aircraft flight stability  

NASA Technical Reports Server (NTRS)

The combined destabilizing effects of roll rate and sideslip angle are studied for a high angle-of-attack flight condition using a linear simulation of the coupled motions of a Space Shuttle-like configuration. Variations in the eigenvalues for a flight condition nominally identified by an angle of attack of 33.29 deg and a Mach number of 4.9 are examined with illustrations of the separate effects of body-axis roll rate and yaw rate, stability-axis roll rate, dynamic pressure, and sideslip angle. It is shown that the stability of the free motion of the vehicle is sensitive to roll rate and that this sensitivity is enhanced by nonzero sideslip angle. The results suggest that fully coupled linearized equations can be of value both for the study of Space Shuttle stability and for a better understanding of post-stall gyrations, incipient spin, and departure prevention for high-performance aircraft.

Stengel, R. F.

1975-01-01

351

STS-93 Mission Specialist Coleman and husband prepare to board aircraft for return flight to Houston  

NASA Technical Reports Server (NTRS)

At the Skid Strip at the Cape Canaveral Air Station, Mission Specialist Catherine G. Coleman (Ph.D.) and her husband, Josh Simpson, 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, Eileen Collins became the first woman to serve as a Shuttle commander.

1999-01-01

352

Comparison of analysis and flight test data for a drone aircraft with active flutter suppression  

NASA Technical Reports Server (NTRS)

This paper presents a comparison of analysis and flight test data for a drone aircraft equipped with an active flutter suppression system. Emphasis is placed on the comparison of modal dampings and frequencies as a function of Mach number. Results are presented for both symmetric and antisymmetric motion with flutter suppression off. Only symmetric results are presented for flutter suppression on. Frequency response functions of the vehicle are presented from both flight test data and analysis. The analysis correlation is improved by using an empirical aerodynamic correction factor which is proportional to the ratio of experimental to analytical steady-state lift curve slope. In addition to presenting the mathematical models and a brief description of existing analytical techniques, an alternative analytical technique for obtaining closed-loop results is presented.

Newsom, J. R.; Pototzky, A. S.

1981-01-01

353

Flight test validation of a frequency-based system identification method on an F-15 aircraft  

NASA Technical Reports Server (NTRS)

A frequency-based performance identification approach was evaluated using flight data from the NASA F-15 Highly Integrated Digital Electronic Control aircraft. The approach used frequency separation to identify the effectiveness of multiple controls simultaneously as an alternative to independent control identification methods. Fourier transformations converted measured control and response data into frequency domain representations. Performance gradients were formed using multiterm frequency matching of control and response frequency domain models. An objective function was generated using these performance gradients. This function was formally optimized to produce a coordinated control trim set. This algorithm was applied to longitudinal acceleration and evaluated using two control effectors: nozzle throat area and inlet first ramp. Three criteria were investigated to validate the approach: simultaneous gradient identification, gradient frequency dependency, and repeatability. This report describes the flight test results. These data demonstrate that the approach can accurately identify performance gradients during simultaneous control excitation independent of excitation frequency.

Schkolnik, Gerard S.; Orme, John S.; Hreha, Mark A.

1995-01-01

354

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

355

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

356

Pitch attitude, flight path, and airspeed control during approach and landing of a powered lift STOL aircraft  

NASA Technical Reports Server (NTRS)

Analytical investigations and piloted moving base simulator evaluations were conducted for manual control of pitch attitude, flight path, and airspeed for the approach and landing of a powered lift jet STOL aircraft. Flight path and speed response characteristics were described analytically and were evaluated for the simulation experiments which were carried out on a large motion simulator. The response characteristics were selected and evaluated for a specified path and speed control technique. These charcteristics were: (1) the initial pitch response and steady pitch rate sensitivity for control of attitude with a pitch rate command/ attitude hold system, (2) the initial flight path response, flight path overshoot, and flight path-airspeed coupling in response to a change in thrust, and (3) the sensitivity of airspeed to pitch attitude changes. Results are presented in the form of pilot opinion ratings and commentary, substantiated where appropriate by response time histories and aircraft states at the point of touchdown.

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

1972-01-01

357

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

358

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

359

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

360

[Flight and altitude medicine for anesthetists-part 3: emergencies on board commercial aircraft].  

PubMed

The demographic trend of industrialized societies is also reflected in commercial airlines' passengers: passengers are older nowadays and long-haul flights are routine mode of transport despite considerable chronic and acute medical conditions. Moreover, duration of non-stop flight routes and the number of passengers on board increase. Thus, the probability of a medical incident during a particular flight event increases, too.Due to international regulations minimum standards for medical equipment on board, and first aid training of the crews are set. However, it is often difficult to assess whether a stopover at a nearby airport can improve the medical care of a critically ill passenger. Besides flight operations and technical aspects, the medical infrastructure on the ground has to be considered carefully.Regardless of the amount of experience of a physician medical emergencies on board an aircraft usually represent a particular challenge. This is mainly due to the unfamiliar surroundings, the characteristics of the cabin atmosphere, the often existing cultural and language barriers and legal liability concerns. PMID:23633251

Graf, Jürgen; Stüben, Uwe; Pump, Stefan

2013-04-01

361

INVESTIGATION OF RADM PERFORMANCE USING AIRCRAFT MEASUREMENTS  

EPA Science Inventory

Measurements using specially instrumented aircraft were obtained during August and September, 1988 as an integral part of the ACID MODES (Model Operational and Diagnostic Evaluation Study) field study. pecialized flights, each designed to diagnose different aspects of the perform...

362

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

363

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

364

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

365

The Mars Science Laboratory (MSL) Mars Descent Imager (MARDI) Flight Instrument  

NASA Astrophysics Data System (ADS)

The MSL Mars Descent Imager (MARDI) flight instrument has been completed and installed on the rover. MARDI will provide hundreds of color images during the descent of MSL to the martian surface in 2012.

Malin, M. C.; Caplinger, M. A.; Edgett, K. S.; Ghaemi, F. T.; Ravine, M. A.; Schaffner, J. A.; Maki, J. N.; Willson, R. G.; Bell, J. F.; Cameron, J. F.; Dietrich, W. E.; Edwards, L. J.; Hallet, B.; Herkenhoff, K. E.; Heydari, E.; Kah, L. C.; Lemmon, M. T.; Minitti, M. E.; Olson, T. S.; Parker, T. J.; Rowland, S. K.; Schieber, J.; Sullivan, R. J.; Sumner, D. Y.; Thomas, P. C.; Yingst, R. A.

2009-03-01

366

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

367

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

368

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

369

Integrated control and display research for transition and vertical flight on the NASA V/STOL Research Aircraft (VSRA)  

NASA Technical Reports Server (NTRS)

Results of a substantial body of ground-based simulation experiments indicate that a high degree of precision of operation for recovery aboard small ships in heavy seas and low visibility with acceptable levels of effort by the pilot can be achieved by integrating the aircraft flight and propulsion controls. The availability of digital fly-by-wire controls makes it feasible to implement an integrated control design to achieve and demonstrate in flight the operational benefits promised by the simulation experience. It remains to validate these systems concepts in flight to establish their value for advanced short takeoff vertical landing (STOVL) aircraft designs. This paper summarizes analytical studies and simulation experiments which provide a basis for the flight research program that will develop and validate critical technologies for advanced STOVL aircraft through the development and evaluation of advanced, integrated control and display concepts, and lays out the plan for the flight program that will be conducted on NASA's V/STOL Research Aircraft (VSRA).

Foster, John D.; Moralez, Ernesto, III; Franklin, James A.; Schroeder, Jeffery A.

1987-01-01

370

Measurements of Long-Lived Trace Gases from Commercial Aircraft Platforms: Development of Instrumentation  

NASA Technical Reports Server (NTRS)

The upper troposphere (6-12 km altitude) is a poorly understood and highly vulnerable region of the atmosphere. It is important because many trace species, including ozone, have their greatest impact as greenhouse (infrared-absorbing) gases in this region. The addition of relatively small amounts of anthropogenic chemicals, such as nitrogen oxides, can have a dramatic effect on the abundance of ozone. Some of these pollutants are deposited directly, e.g., by aircraft, while others are transported in. The primary goal of this project was to measure several chemical compounds in the upper troposphere that will help us to understand how air is to transported to that part of the atmosphere; that is, does it come down from the stratosphere, does it rise from the surface via convection, and so on. To obtain adequate sampling to accomplish this goal, we proposed to make measurements from revenue aircraft during normal flight operations.

2002-01-01

371

Longitudinal stability and control derivatives obtained from flight data of a PA-30 aircraft  

NASA Technical Reports Server (NTRS)

In order to obtain reliable and accurate values of the stability and control derivatives, the Dryden Fligh Research Center (DFRC) developed a technique for extracting the derivatives from flight data. This technique is implemented by a set of FORTRAN computer programs that is based on a modified maximum likelihood estimator that uses the Newton-Raphson algorithm to perform the required minimization of the derivatives. Data was obtained with a PA-30, light twin-engine general aviation aircraft in zero, half, and full flap configuration in level unaccelerated flight with the landing gear retracted. The derivatives were plotted as functions of angle of attack using various graphical arrangements to show variations of wind tunnel and flight determined values at zero flap settings. Also, data was displayed to show the effects of flap deflection and thrust variation on the longitudinal stability derivatives. The angle of attack and angle of sideslip were measured. The dynamic pressure, velocity, and altitude were calculated, using a FORTRAN computer program, from the static and dynamic pressures. The control deflections of the stabilator, ailerons, and rudder also were recorded along with left throttle position, engine rpm, and manifold pressure.

Turley, D. R.; Sandlin, D. R.

1981-01-01

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

Preliminary Flight Tests of the N.A.C.A. Roots Type Aircraft Engine Supercharger  

NASA Technical Reports Server (NTRS)

An investigation of the suitability of the N.A.C.A. Roots type aircraft engine supercharger to flight-operating conditions, as determined the effects of the use of the supercharger upon engine operation and airplane performance, is described in this report. Attention was concentrated on the operation of the engine-supercharger unit and on the improvement of climbing ability; some information concerning high speeds at altitude was obtained. The supercharger was found to be satisfactory under flight-operating conditions. Although two failures occurred during the tests, the causes of both were minor and have been eliminated. Careful examination of the engines revealed no detrimental effects which could be attributed to supercharging. Marked improvements in climbing ability and high speeds at altitude were effected. It was also found that the load which could be carried to a given moderate or high altitude in a fixed time was considerably augmented. A slight sacrifice of low-altitude performance was necessitated, however, by the use of a fixed-pitch propeller. From a consideration of the very satisfactory flight performance of the Roots supercharger and of its inherent advantages, it is concluded that this type is particularly attractive for use in certain classes of commercial airplanes and in a number of military types.

Gardiner, Arthur W; Reid, Elliott G

1928-01-01

374

Design, implementation and flight testing of PIF autopilots for general aviation aircraft  

NASA Technical Reports Server (NTRS)

The designs of Proportional-Integrated-Filter (PIF) auto-pilots for a General Aviation (NAVION) aircraft are presented. The PIF autopilot uses the sampled-data regulator and command generator tracking to determine roll select, pitch select, heading select, altitude select and localizer/glideslope capture and hold autopilot modes. The PIF control law uses typical General Aviation sensors for state feedback, command error integration for command tracking, digital complementary filtering and analog prefiltering for sensor noise suppression, a control filter for computation delay accommodation and the incremental form to eliminate trim values in implementation. Theoretical developments described in detail, were needed to combine the sampled-data regulator with command generator tracking for use as a digital flight control system. The digital PIF autopilots are evaluated using closed-loop eigenvalues and linear simulations. The implementation of the PIF autopilots in a digital flight computer using a high order language (FORTRAN) is briefly described. The successful flight test results for each PIF autopilot mode is presented.

Broussard, J. R.

1983-01-01

375

Summary of 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. Automated systems have become more complex and numerous, and often their inner functioning is partially or fully opaque to the flight crew. Recent accidents and incidents involving autoflight system mode awareness Dornheim, 1995) are an example. This increase in complexity raises pilot concerns about the trustworthiness of automation, and makes it difficult for the crew to be aware of all the intricacies of operation that may impact safe flight. While pilots remain ultimately responsible for mission success, performance of flight deck tasks has been more widely distributed across human and automated resources. Advances in sensor and data integration technologies now make far more information available than may be prudent to present to the flight crew.

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

1995-01-01

376

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

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

Application experience with the NASA aircraft interrogation and display system - A ground-support equipment for digital flight systems  

NASA Technical Reports Server (NTRS)

The NASA Dryden Flight Research Facility has developed a microprocessor-based, user-programmable, general-purpose aircraft interrogation and display system (AIDS). The hardware and software of this ground-support equipment have been designed to permit diverse applications in support of aircraft digital flight-control systems and simulation facilities. AIDS is often employed to provide engineering-units display of internal digital system parameters during development and qualification testing. Such visibility into the system under test has proved to be a key element in the final qualification testing of aircraft digital flight-control systems. Three first-generation 8-bit units are now in service in support of several research aircraft projects, and user acceptance has been high. A second-generation design, extended AIDS (XAIDS), incorporating multiple 16-bit processors, is now being developed to support the forward swept wing aircraft project (X-29A). This paper outlines the AIDS concept, summarizes AIDS operational experience, and describes the planned XAIDS design and mechanization.

Glover, R. D.

1983-01-01

379

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

380

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

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

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

383

Flight dynamics of a pterosaur-inspired aircraft utilizing a variable-placement vertical tail.  

PubMed

Mission performance for small aircraft is often dependent on the turn radius. Various biologically inspired concepts have demonstrated that performance can be improved by morphing the wings in a manner similar to birds and bats; however, the morphing of the vertical tail has received less attention since neither birds nor bats have an appreciable vertical tail. This paper investigates a design that incorporates the morphing of the vertical tail based on the cranial crest of a pterosaur. The aerodynamics demonstrate a reduction in the turn radius of 14% when placing the tail over the nose in comparison to a traditional aft-placed vertical tail. The flight dynamics associated with this configuration has unique characteristics such as a Dutch-roll mode with excessive roll motion and a skid divergence that replaces the roll convergence. PMID:21558603

Roberts, Brian; Lind, Rick; Chatterjee, Sankar

2011-06-01

384

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

385

Comparison of analysis and flight test data for a drone aircraft with active flutter suppression  

NASA Technical Reports Server (NTRS)

A drone aircraft equipped with an active flutter suppression system is considered with emphasis on the comparison of modal dampings and frequencies as a function of Mach number. Results are presented for both symmetric and antisymmetric motion with flutter suppression off. Only symmetric results are given for flutter suppression on. Frequency response functions of the vehicle are presented from both flight test data and analysis. The analysis correlation is improved by using an empirical aerodynamic correction factor which is proportional to the ratio of experimental to analytical steady-state lift curve slope. The mathematical models are included and existing analytical techniques are described as well as an alternative analytical technique for obtaining closed-loop results.

Newsom, J. R.; Pototzky, A. S.

1981-01-01

386

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

387

The Shuttle Carrier Aircraft, with Columbia on top, gets ready for the flight to California  

NASA Technical Reports Server (NTRS)

The Boeing 747 Shuttle Carrier Aircraft, with the orbiter Columbia strapped to its back, waits at the Shuttle Landing Facility for clear weather to take off for its final destination, Palmdale, Calif. The oldest of four orbiters in NASA's fleet, Columbia is being ferried to Palmdale to undergo extensive inspections and modifications in Boeing's Orbiter Assembly Facility. The nine-month orbiter maintenance down period (OMDP) is the second in Columbia's history. Orbiters are periodically removed from flight operations for an OMDP. Columbia's first was in 1994. Along with more than 100 modifications on the vehicle, Columbia will be the second orbiter to be outfitted with the multifunctional electronic display system, or 'glass cockpit.' Columbia is expected to return to KSC in July 2000.

1999-01-01

388

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

389

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 five 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 solid laminate under-wing fillet panel; and a 150 C (300 F) service aft engine fairing. The fairings have accumulated a total of 40,534 hours, with one ship set having 16,091 hours service as of Feb. 11, 1979. 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.

Stone, R. H.

1979-01-01

390

Flight-test results using nonlinear control with the F-8C digital fly-by-wire aircraft  

NASA Technical Reports Server (NTRS)

The design and operation of the cooperative advanced digital research experiment (CADRE) to develop nonlinear pitch flight control algorithms is described, and the results of an in-flight evaluation using the F-8C digital fly-by-wire (DFBW) research aircraft are presented. The CADRE controller is described, including the initial filter, linear command prefilter, nonlinear command prefilter, and gain scheduling. The variable-integral control-to-optimize response of the controller is considered, and CADRE parameter combinations are addressed. The remotely-augmented-vehicle interface used in the DFBW aircraft experiment is discussed. The distanct-tracking and close-formation tracking evaluation tasks for the aircraft are described along with evaluation configurations, and the test results are presented and discussed. The latter indicate that a nonlinear adaptive controller is a feasible control system technique for the fighter tracking task.

Larson, R. R.; Smith, R. E.; Krambeer, K. D.

1983-01-01

391

14 CFR 29.1303 - Flight and navigation instruments.  

Code of Federal Regulations, 2012 CFR

...temperature indicator. (f) A non-tumbling gyroscopic bank and pitch indicator. (g) A gyroscopic rate-of-turn indicator... (1) Is usable through flight attitudes of ±80 degrees of pitch and ±120 degrees of roll; (2) Is powered from a...

2012-01-01

392

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

393

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

394

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

395

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

396

14 CFR 23.1303 - Flight and navigation instruments.  

Code of Federal Regulations, 2010 CFR

...instruments: (a) An airspeed indicator. (b) An altimeter. (c) A direction indicator (nonstabilized magnetic compass). (d) For reciprocating engine-powered airplanes of more than 6,000 pounds maximum weight and...

2010-01-01

397

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

Code of Federal Regulations, 2012 CFR

...clause may be modified as follows: If the contract covers helicopters, vertical take-off aircraft, lighter-than-air airships, or other nonconventional types of aircraft, the definition of “aircraft” should be modified to specify that the...

2012-10-01

398

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

Code of Federal Regulations, 2011 CFR

...clause may be modified as follows: If the contract covers helicopters, vertical take-off aircraft, lighter-than-air airships, or other nonconventional types of aircraft, the definition of “aircraft” should be modified to specify that the...

2011-10-01

399

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

Code of Federal Regulations, 2014 CFR

...clause may be modified as follows: If the contract covers helicopters, vertical take-off aircraft, lighter-than-air airships, or other nonconventional types of aircraft, the definition of “aircraft” should be modified to specify that the...

2014-10-01

400

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

Code of Federal Regulations, 2013 CFR

...clause may be modified as follows: If the contract covers helicopters, vertical take-off aircraft, lighter-than-air airships, or other nonconventional types of aircraft, the definition of “aircraft” should be modified to specify that the...

2013-10-01

401

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

402