These are representative sample records from Science.gov related to your search topic.
For comprehensive and current results, perform a real-time search at Science.gov.
1

Trust Control of VTOL Aircraft Part Deux  

NASA Technical Reports Server (NTRS)

Thrust control of Vertical Takeoff and Landing (VTOL) aircraft has always been a debatable issue. In most cases, it comes down to the fundamental question of throttle versus collective. Some aircraft used throttle(s), with a fore and aft longitudinal motion, some had collectives, some have used Thrust Levers where the protocol is still "Up is Up and Down is Down," and some have incorporated both throttles and collectives when designers did not want to deal with the Human Factors issues. There have even been combinations of throttles that incorporated an arc that have been met with varying degrees of success. A previous review was made of nineteen designs without attempting to judge the merits of the controller. Included in this paper are twelve designs entered in competition for the 1961 Tri-Service VTOL transport. Entries were from a Bell/Lockheed tiltduct, a North American tiltwing, a Vanguard liftfan, and even a Sikorsky tiltwing. Additional designs were submitted from Boeing Wichita (direct lift), Ling-Temco-Vought with its XC-142 tiltwing, Boeing Vertol's tiltwing, Mcdonnell's compound and tiltwing, and the Douglas turboduct and turboprop designs. A private party submitted a re-design of the Breguet 941 as a VTOL transport. It is important to document these 53 year-old designs to preserve a part of this country's aviation heritage.

Dugan, Daniel C.

2014-01-01

2

The design of digital-adaptive controllers for VTOL aircraft  

NASA Technical Reports Server (NTRS)

Design procedures for VTOL automatic control systems have been developed and are presented. Using linear-optimal estimation and control techniques as a starting point, digital-adaptive control laws have been designed for the VALT Research Aircraft, a tandem-rotor helicopter which is equipped for fully automatic flight in terminal area operations. These control laws are designed to interface with velocity-command and attitude-command guidance logic, which could be used in short-haul VTOL operations. Developments reported here include new algorithms for designing non-zero-set-point digital regulators, design procedures for rate-limited systems, and algorithms for dynamic control trim setting.

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

1976-01-01

3

Experimental investigations of thrust vectoring systems for VTOL aircraft  

NASA Technical Reports Server (NTRS)

This paper presents a summary of two technology programs sponsored by NASA to investigate the characteristics of two thrust vectoring schemes for V/STOL aircraft. The operational capability of the VTOL aircraft is dependent on maximum utilization of the installed thrust in both the cruise and powered lift modes of flight. An effective thrust vectoring system on the cruise propulsion unit is therefore essential to provide maximum payload in hover and STOL plus minimum specific fuel consumption in loiter and cruise. Introducing a high by-pass ratio fan system, augmenting the gas generator thrust, as the propulsion system for VTOL aircraft places increased significance on the performance of the relatively short coupled thrust vectoring systems. The two programs discussed herein include both large-scale and small-scale tests of a vectoring hood system with a vented, internal-lip and swivel nozzle systems. These tests indicated that a satisfactory thrust vectoring system can be developed.

Rolls, L. S.; Aoyagi, K.

1977-01-01

4

Control of turbofan lift engines for VTOL aircraft  

NASA Technical Reports Server (NTRS)

The use of turbofan engines as lift units for VTOL aircraft poses new engine control problems. At low flight speeds, the lift units must provide the fast thrust response needed for aircraft attitude and height control. The results are presented of an analytical study of the dynamics and control of turbofan lift engines, and methods are proposed for meeting the response requirements imposed by the VTOL aircraft application. Two types of lift fan engines are discussed: the integral and remote. The integral engine is a conventional two-spool, high bypass ratio turbofan designed for low noise and short length. The remote engine employs a gas generator and a lift fan which are separated by a duct, and which need not be coaxial. For the integral engine, a control system design is presented which satisfies the VTOL response requirements. For the remote engine, two unconventional methods of control involving flow transfer between lift units are discussed. Both methods are shown to have thrust response near the required levels.

Sellers, J. F.; Szuch, J. R.

1973-01-01

5

Benefits of VTOL aircraft in offshore petroleum logistics support  

NASA Technical Reports Server (NTRS)

The mission suitability and potential economic benefits of advanced VTOL aircraft were investigated for logistics support of petroleum operations in the North Sea and the Gulf of Mexico. Concepts such as the tilt rotor and lift/cruise fan are promising for future operations beyond 150 miles offshore, where their high cruise efficiency provides savings in trip time, fuel consumption, and capital investment. Depending upon mission requirements, the aircraft operating costs are reduced by as much as 20 percent to 50 percent from those of current helicopters.

Wilcox, D. E.; Shovlin, M. D.

1975-01-01

6

Control of turbofan lift engines for VTOL aircraft.  

NASA Technical Reports Server (NTRS)

This paper presents the results of an analytical study of the dynamics and control of turbofan lift engines, and proposes methods of meeting the response requirements imposed by the VTOL aircraft application. Two types of lift fan engines are discussed: the integral and remote. The integral engine is a conventional two-spool, high bypass ratio turbofan designed for low noise and short length. The remote engine employs a gas generator and a lift fan which are separated by a duct, and which need not be coaxial. For the integral engine, a control system design is presented which satisfies the VTOL response requirements. For the remote engine, two unconventional methods of control involving flow transfer between lift units are discussed.

Sellers, J. F.; Szuch, J. R.

1973-01-01

7

Display/control requirements for VTOL aircraft  

NASA Technical Reports Server (NTRS)

Quantative metrics were determined for system control performance, workload for control, monitoring performance, and workload for monitoring. Pilot tasks were allocated for navigation and guidance of automated commercial V/STOL aircraft in all weather conditions using an optimal control model of the human operator to determine display elements and design.

Hoffman, W. C.; Curry, R. E.; Kleinman, D. L.; Hollister, W. M.; Young, L. R.

1975-01-01

8

Attitude stabilization of a VTOL quadrotor aircraft  

Microsoft Academic Search

In this paper, we propose a new quaternion-based feedback control scheme for exponential attitude stabilization of a four-rotor vertical takeoff and landing aerial robot known as a quadrotor aircraft. The proposed controller is based upon the compensation of the Coriolis and gyroscopic torques and the use of a PD2 feedback structure, where the proportional action is in terms of the

Abdelhamid Tayebi; Stephen McGilvray

2006-01-01

9

Effect of stabilization on VTOL aircraft in hovering flight  

NASA Technical Reports Server (NTRS)

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

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

1972-01-01

10

Flight control simulators for unmanned fixed-wing and VTOL aircraft  

Microsoft Academic Search

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

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

2009-01-01

11

Modelling and Control of a Convertible VTOL Aircraft J. Escareo, S. Salazar and R. Lozano.  

E-print Network

Modelling and Control of a Convertible VTOL Aircraft J. Escareño, S. Salazar and R. Lozano. Abstract-- The aim of this paper is to present the complete model of an unmanned convertible aerial vehicle control strategy is presented to stabilize the aircraft in hovering mode. An embedded low-cost pilot

Sontag, Eduardo

12

Flow visualization studies of VTOL aircraft models during Hover in ground effect  

NASA Technical Reports Server (NTRS)

A flow visualization study of several configurations of a jet-powered vertical takeoff and landing (VTOL) aircraft model during hover in ground effect was conducted. A surface oil flow technique was used to observe the flow patterns on the lower surfaces of the model. There were significant configuration effects. Wing height with respect to fuselage, the presence of an engine inlet duct beside the fuselage, and nozzle pressure ratio are seen to have strong effects on the surface flow angles on the lower surface of the wing. This test was part of a program to improve the methods for predicting the hot gas ingestion (HGI) for jet-powered vertical/short takeoff and landing (V/STOL) aircraft. The tests were performed at the Jet Calibration and Hover Test (JCAHT) Facility at Ames Research Center.

Mourtos, Nikos J.; Couillaud, Stephane; Carter, Dale; Hange, Craig; Wardwell, Doug; Margason, Richard J.

1995-01-01

13

Benefits of Hybrid-Electric Propulsion to Achieve 4x Increase in Cruise Efficiency for a VTOL Aircraft  

NASA Technical Reports Server (NTRS)

Electric propulsion enables radical new vehicle concepts, particularly for Vertical Takeoff and Landing (VTOL) aircraft because of their significant mismatch between takeoff and cruise power conditions. However, electric propulsion does not merely provide the ability to normalize the power required across the phases of flight, in the way that automobiles also use hybrid electric technologies. The ability to distribute the thrust across the airframe, without mechanical complexity and with a scale-free propulsion system, is a new degree of freedom for aircraft designers. Electric propulsion is scale-free in terms of being able to achieve highly similar levels of motor power to weight and efficiency across a dramatic scaling range. Applying these combined principles of electric propulsion across a VTOL aircraft permits an improvement in aerodynamic efficiency that is approximately four times the state of the art of conventional helicopter configurations. Helicopters typically achieve a lift to drag ratio (L/D) of between 4 and 5, while the VTOL aircraft designed and developed in this research were designed to achieve an L/D of approximately 20. Fundamentally, the ability to eliminate the problem of advancing and retreating rotor blades is shown, without resorting to unacceptable prior solutions such as tail-sitters. This combination of concept and technology also enables a four times increase in range and endurance while maintaining the full VTOL and hover capability provided by a helicopter. Also important is the ability to achieve low disc-loading for low ground impingement velocities, low noise and hover power minimization (thus reducing energy consumption in VTOL phases). This combination of low noise and electric propulsion (i.e. zero emissions) will produce a much more community-friendly class of vehicles. This research provides a review of the concept brainstorming, configuration aerodynamic and mission analysis, as well as subscale prototype construction and flight testing that verifies transition flight control. A final down-selected vehicle is also presented.

Fredericks, William J.; Moore, Mark D.; Busan, Ronald C.

2013-01-01

14

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

15

An investigation of automatic guidance concepts to steer a VTOL aircraft to a small aviation facility ship  

NASA Technical Reports Server (NTRS)

A detailed system model of a VTOL aircraft approaching a small aviation facility ship was developed and used to investigate several approach guidance concepts. A preliminary anaysis of the aircraft-vessel landing guidance requirements was conducted. The various subelements and constraints of the flight system are described including the landing scenario, lift fan aircraft, state rate feedback flight control, MLS-based navigation, sea state induced ship motion, and wake turbulence due to wind-over-deck effects. These elements are integrated into a systems model with various guidance concepts. Guidance is described in terms of lateral, vertical, and longitudinal axes steering modes and approach and landing phases divided by a nominal hover (or stationkeeping) point defined with respect to the landing pad. The approach guidance methods are evaluated, and the two better steering concepts are studied by both single pass and Monte Carlo statistical simulation runs. Four different guidance concepts are defined for further analysis for the landing phase of flight.

Sorensen, J. A.; Goka, T.; Phatak, A. V.; Schmidt, S. F.

1980-01-01

16

Open airscrew VTOL concepts  

NASA Technical Reports Server (NTRS)

The following concepts, based on using open airscrew(s) for VTOL maneuvers, are re-examined in light of current technology: (1) tip-driven helicopters, (2) compound helicopters; and (3) high-speed VTOL aircraft, represented by tiltrotors, tiltwings, retractoplanes and stoppable rotors. Criteria, permitting one to compare performance of aircraft using diverse lifting and propelling methods are established. Determination of currently possible performance, indication of near-future potentials, and comparison of those items with the baseline levels (as represented by contemporary shaft-driven helicopters, first generation tiltrotors, and commercial turboprop fixed-wind aircraft) constitutes bulk of this report.

Stepniewski, W. Z.; Tarczynski, T.

1992-01-01

17

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

NASA Technical Reports Server (NTRS)

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

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

1974-01-01

18

Studies in tilt-rotor VTOL aircraft aeroelasticity, volume 1. Ph.D. Thesis - Case Western Reserve Univ.  

NASA Technical Reports Server (NTRS)

Aeroelastic and dynamic studies which complement and extend various aspects of technology applicable to tilt-rotor VTOL aircraft are discussed. Particular attention is given to proprotor/pylon whirl instability, a precession-type instability akin to propeller/nacelle whirl flutter. The blade flapping and pitch-change freedoms of a proprotor are shown to lead to a fundamentally different situation as regards the manner in which the precession-generated aerodynamic forces and moments act on the pylon and induce whirl flutter relative to that of a propeller. The implication of these forces and moments with regard to their capacity for instigating a whirl instability is examined, demonstrating why a proprotor can exhibit whirl flutter in either the backward or forward directions in contrast to a propeller which is found to always whirl in the backward direction. Analytical trend studies delineating the effect of several system design parameters on proprotor/pylon stability and response are shown.

Kvaternik, R. G.

1973-01-01

19

A Preliminary Study of V/STOL Transport Aircraft and Bibliography of NASA Research in the VTOL-STOL Field  

NASA Technical Reports Server (NTRS)

This group of papers was prepared by the staff of the Langley Research Center to assist in planning for future commercial air-transport facilities in the New York metropolitan area. Areas of particular interest were predictions regarding the types of V/STOL aircraft that are likely to be developed for various commercial transport applications, estimates of the performance and probable operating procedures for such aircraft, and the approximate dates these aircraft could be available for use. Although the NASA has made no comprehensive studies of this type, the extensive research program in the VTOL-STOL field during the last 10 years appeared to provide a source for some of the desired information . The five papers included herein were therefore prepared to summarize pertinent available material in a form suitable for the intended use. In several instances, new studies and analysis were required to provide the necessary information, but because of a time deadline, many of the significant points received only a cursory examination. For example, much of the quantitative data used in the papers for making generalized comparisons was obtained by approximate methods and is not considered appropriate for use in applications where precise estimates are required. It should be recognized, then, that the treatment of the V/STOL transport provided by this group of papers is necessarily of a preliminary nature.

1961-01-01

20

Development of the NASA VALT digital navigation system. [for approach and landing procedures of VTOL aircraft  

NASA Technical Reports Server (NTRS)

The research to develop and fabricate a terminal area navigation system for use in the NASA VTOL Approach and Landing Technology (VALT) program. The results of that effort are reported. The navigation system developed and fabricated was based on a general purpose airborne digital computer. A set of flight hardware units was fabricated to create the necessary analog, digital and human interface with the computer. A comprehensive package of software was created to implement the control and guidance laws required for automatic and flight director approaches that are curved in two planes. A technique was developed that enables the generation of randomly shaped lateral paths from simple input data. The lateral path concept combines straight line and elliptical-curved segments to fit a continuous curved path to the data points. A simple, fixed base simulation was put together to assist in developing and evaluating the system. The simulation was used to obtain system performance data during simulated curved-path approaches.

Mcconnell, W. J., Jr.; Skutecki, E. R.; Calzado, A. J.

1975-01-01

21

Investigation of Flow Instabilities in the Inlet Ducts of DP-1C VTOL Aircraft  

NASA Technical Reports Server (NTRS)

An investigation of flow instabilities in the inlet ducts of a two-engine vertical takeoff and landing aircraft DP-1C is described in this report. Recent tests revealed that the engines stall during run ups while the aircraft is operating on the ground. These pop stalls occurred at relatively low power levels, sometimes as low as 60 percent of the engine full speed. Inability to run the engines up to the full speed level is attributed to in-ground effects associated with hot gas ingestion. Such pop stalls were never experienced when the aircraft was tested on a elevated grid platform, which ensured that the aircraft was operating in out-of-the-ground-effect conditions. Based on available information on problems experienced with other vertical takeoff and landing aircraft designs, it was assumed that the engine stalls were caused by partial ingestion of hot gases streaming forward from the main exit nozzle under the aircraft inlets, which are very close to the ground. It was also suggested that the nose wheel undercarriage, located between the inlets, may generate vortices or an unstable wake causing intense mixing of hot exit gases with incoming inlet flow, which would enhance the hot gas ingestion. After running a short three-day series of tests with fully instrumented engine inlets, it is now believed the most probable reason for engine pop stalls are random ingestions of a vortex generated between the two streams moving in opposite directions: outbound hot gas stream from the main nozzle close to the ground and inbound inlet flow above. Originally, the vortex is in a horizontal plane. However, at a certain velocity ratio of these two streams, the vortex attaches either to the ground or the aircraft surface at one end and the other end is swallowed by one of the aircraft inlets. Once the vortex enters the inlet duct, a puff of hot air can be sucked through the vortex core into the engine, which causes a serious inlet flow field distortion followed by an engine stall. Once the engine stalls, the outflow from the inlet pushes the vortex away and the engine resumes normal operation. This hypothesis needs to be verified experimentally; e.g., by extensive smoke flow visualization ahead of the aircraft inlets.

Lepicovsky, Jan

2008-01-01

22

VTOL controls for shipboard operations  

NASA Technical Reports Server (NTRS)

Piloted, moving-base simulations have been performed in the evaluation of several VTOL control system concepts during landings on a destroyer in adverse weather conditions. All the systems incorporated attitude control augmentation; most systems incorporated various types of translational control augmentation implemented either through aircraft attitude or, more directly, through the propulsion system (thrust magnitude and deflection). Only one of the control systems failed to provide satisfactory handling qualities in calm seas. Acceptable handling qualities in sea state 6 seem to require a system with control augmentation in all translational degrees of freedom.

Merrick, V. K.; Gerdes, R. M.

1983-01-01

23

VTOL in ground effect flows for closely spaced jets. [to predict pressure and upwash forces on aircraft structures  

NASA Technical Reports Server (NTRS)

Results of a series of in ground effect twin jet tests are presented along with flow models for closely spaced jets to help predict pressure and upwash forces on simulated aircraft surfaces. The isolated twin jet tests revealed unstable fountains over a range of spacings and jet heights, regions of below ambient pressure on the ground, and negative pressure differential in the upwash flow field. A separate computer code was developed for vertically oriented, incompressible jets. This model more accurately reflects fountain behavior without fully formed wall jets, and adequately predicts ground isobars, upwash dynamic pressure decay, and fountain lift force variation with height above ground.

Migdal, D.; Hill, W. G., Jr.; Jenkins, R. C.

1979-01-01

24

Attitude controls for VTOL aircraft  

NASA Technical Reports Server (NTRS)

Systems consist of single duct system with two sets of reaction control nozzles, one linked mechanically to pilot's controls, and other set driven by electric servomotors commanded by preselected combinations of electrical signals.

Pauli, F. A.

1971-01-01

25

Design and evaluation of an integrated flight-control system concept for manual IFR VTOL operations  

NASA Technical Reports Server (NTRS)

An integrated flight controller, display, and power management system design, suitable for all-weather VTOL flight operations onto small ships, is described. The flight controller uncouples the aircraft's translational and attitude motions, which are then commanded by the pilot, through separate controls. A head-up display provides situation and flight director information sufficient to permit zero-zero landings. The system was applied to a VTOL transport model and simulated on moving base simulators at Ames Research Center. Presented herein are results concerning the aircraft's general handling qualities and, in particular, its handling qualities during IFR landings onto a moving ship.

Merrick, V. K.; Gerdes, R. M.

1977-01-01

26

An in-flight simulation of VTOL hover control concepts  

NASA Technical Reports Server (NTRS)

Results of several parametric ground-based simulations covering a variety of VTOL in-hover control concepts are reviewed. The systems considered are angular acceleration, rate, and attitude control, as well as translational rate control. Since many cues are severely restricted by ground-based simulation (e.g., motion, peripheral vision, and environment), some form of in-flight validation of these results is desired. Such a study has been undertaken utilizing the NASA Ames X-14B VTOL aircraft. This in-flight simulator has been configured with a fly-by-wire capability in the hover mode through an analog-/digital variable stability system. This system permits the implementation of either response-feedback or model-following type of control. A comparison of flight- and ground-based data is shown for the attitude control system with the X-14B being flown in both a tethered hover and a free-flight hover.

Corliss, L. D.; Greif, R. K.; Gerdes, R. M.

1977-01-01

27

Analysis of navigation and guidance requirements for commercial VTOL operations  

NASA Technical Reports Server (NTRS)

The paper presents some results of a program undertaken to define navigation and guidance requirements for commercial VTOL operations in the takeoff, cruise, terminal and landing phases of flight in weather conditions up to and including Category III. Quantitative navigation requirements are given for the parameters range, coverage, operation near obstacles, horizontal accuracy, multiple landing aircraft, multiple pad requirements, inertial/radio-inertial requirements, reliability/redundancy, update rate, and data link requirements in all flight phases. A multi-configuration straw-man navigation and guidance system for commercial VTOL operations is presented. Operation of the system is keyed to a fully automatic approach for navigation, guidance and control, with pilot as monitor-manager. The system is a hybrid navigator using a relatively low-cost inertial sensor with DME updates and MLS in the approach/departure phases.

Hoffman, W. C.; Zvara, J.; Hollister, W. M.

1975-01-01

28

VTOL controls for shipboard landing. M.S.Thesis  

NASA Technical Reports Server (NTRS)

The problem of landing a VTOL aircraft on a small ship in rough seas using an automatic controller is examined. The controller design uses the linear quadratic Gaussian results of modern control theory. Linear time invariant dynamic models are developed for the aircraft, ship, and wave motions. A hover controller commands the aircraft to track position and orientation of the ship deck using only low levels of control power. Commands for this task are generated by the solution of the steady state linear quadratic gaussian regulator problem. Analytical performance and control requirement tradeoffs are obtained. A landing controller commands the aircraft from stationary hover along a smooth, low control effort trajectory, to a touchdown on a predicted crest of ship motion. The design problem is formulated and solved as an approximate finite-time linear quadratic stochastic regulator. Performance and control results are found by Monte Carlo simulations.

Mcmuldroch, C. G.

1979-01-01

29

Maintenance cost studies of rotary wing commercial transport aircraft  

E-print Network

Introduction: The vertical take-off and landing (VTOL) aircraft market has had substantial growth in the period of the last ten years when one considers the overall number of aircraft in use. The military fleet has continued ...

Ausrotas, Raymond A.

1974-01-01

30

Digital adaptive controllers for VTOL vehicles. Volume 1: Concept evaluation  

NASA Technical Reports Server (NTRS)

A digital self-adaptive flight control system was developed for flight test in the VTOL approach and landing technology (VALT) research aircraft (a modified CH-47 helicopter). The control laws accept commands from an automatic on-board guidance system. The primary objective of the control laws is to provide good command-following with a minimum cross-axis response. Three attitudes and vertical velocity are separately commanded. Adaptation of the control laws is based on information from rate and attitude gyros and a vertical velocity measurement. The final design resulted from a comparison of two different adaptive concepts--one based on explicit parameter estimates from a real-time maximum-likelihood estimation algorithm, the other based on an implicit model reference adaptive system. The two designs were compared on the basis of performance and complexity.

Hartmann, G. L.; Stein, G.; Pratt, S. G.

1979-01-01

31

In-flight research applications of an analog computer and symbol generator to determine display and control requirements for VTOL instrument landings  

NASA Technical Reports Server (NTRS)

This paper describes the design and application of an airborne analog computer and display generator. The system was developed as an aid to investigate the interaction of display system complexity and control system complexity on pilot rating and performance for VTOL aircraft instrument landings.

Beilman, J. L.; Gavin, T. J.; Till, R. D.

1975-01-01

32

Performance, physiological, and oculometer evaluation of VTOL landing displays  

NASA Technical Reports Server (NTRS)

A methodological approach to measuring workload was investigated for evaluation of new concepts in VTOL aircraft displays. Physiological, visual response, and conventional flight performance measures were recorded for landing approaches performed in the NASA Visual Motion Simulator (VMS). Three displays (two computer graphic and a conventional flight director), three crosswind amplitudes, and two motion base conditions (fixed vs. moving base) were tested in a factorial design. Multivariate discriminant functions were formed from flight performance and/or visual response variables. The flight performance variable discriminant showed maximum differentation between crosswind conditions. The visual response measure discriminant maximized differences between fixed vs. motion base conditions and experimental displays. Physiological variables were used to attempt to predict the discriminant function values for each subject/condition trial. The weights of the physiological variables in these equations showed agreement with previous studies. High muscle tension, light but irregular breathing patterns, and higher heart rate with low amplitude all produced higher scores on this scale and thus represent higher workload levels.

North, R. A.; Stackhouse, S. P.; Graffunder, K.

1979-01-01

33

Aircraft  

DOEpatents

This disclosure provides a solar rechargeable aircraft that is inexpensive to produce, is steerable, and can remain airborne almost indefinitely. The preferred aircraft is a span-loaded flying wing, having no fuselage or rudder. Travelling at relatively slow speeds, and having a two-hundred foot wingspan that mounts photovoltaic cells on most all of the wing's top surface, the aircraft uses only differential thrust of its eight propellers to turn. Each of five sections of the wing has one or more engines and photovoltaic arrays, and produces its own lift independent of the other sections, to avoid loading them. Five two-sided photovoltaic arrays, in all, are mounted on the wing, and receive photovoltaic energy both incident on top of the wing, and which is incident also from below, through a bottom, transparent surface. The aircraft is capable of a top speed of about ninety miles per hour, which enables the aircraft to attain and can continuously maintain altitudes of up to sixty-five thousand feet. Regenerative fuel cells in the wing store excess electricity for use at night, such that the aircraft can sustain its elevation indefinitely. A main spar of the wing doubles as a pressure vessel that houses hydrogen and oxygen gasses for use in the regenerative fuel cell. The aircraft has a wide variety of applications, which include weather monitoring and atmospheric testing, communications, surveillance, and other applications as well.

Hibbs, Bart D. (1732 N. Grand Oaks, Altadena, CA 91001); Lissaman, Peter B. S. (3276 Rubio Canyon Rd., Altadena, CA 91001); Morgan, Walter R. (3217 Amarillo Ave., Simi Valley, CA 93063); Radkey, Robert L. (70 Eddystone Ct., Redwood City, CA 94065)

1998-01-01

34

Aircraft  

DOEpatents

This disclosure provides a solar rechargeable aircraft that is inexpensive to produce, is steerable, and can remain airborne almost indefinitely. The preferred aircraft is a span-loaded flying wing, having no fuselage or rudder. Travelling at relatively slow speeds, and having a two-hundred foot wingspan that mounts photovoltaic cells on most all of the wing`s top surface, the aircraft uses only differential thrust of its eight propellers to turn. Each of five sections of the wing has one or more engines and photovoltaic arrays, and produces its own lift independent of the other sections, to avoid loading them. Five two-sided photovoltaic arrays, in all, are mounted on the wing, and receive photovoltaic energy both incident on top of the wing, and which is incident also from below, through a bottom, transparent surface. The aircraft is capable of a top speed of about ninety miles per hour, which enables the aircraft to attain and can continuously maintain altitudes of up to sixty-five thousand feet. Regenerative fuel cells in the wing store excess electricity for use at night, such that the aircraft can sustain its elevation indefinitely. A main spar of the wing doubles as a pressure vessel that houses hydrogen and oxygen gases for use in the regenerative fuel cell. The aircraft has a wide variety of applications, which include weather monitoring and atmospheric testing, communications, surveillance, and other applications as well. 31 figs.

Hibbs, B.D.; Lissaman, P.B.S.; Morgan, W.R.; Radkey, R.L.

1998-09-22

35

Small V/STOL aircraft analysis, volume 1  

NASA Technical Reports Server (NTRS)

A study has been made of the economic viability of advanced V/STOL aircraft concepts in performing general aviation missions. A survey of general aviation aircraft users, operators, and manufacturers indicated that personnel transport missions formulated around business executive needs, commuter air service, and offshore oil supply are the leading potential areas of application using VTOL aircraft. Advanced VTOL concepts potentially available in the late 1970 time period were evaluated as alternatives to privately owned contemporary aircraft and commercial airline service in satisfying these personnel transport needs. Economic analysis incorporating the traveler's value of time as the principle figure of merit were used to identify the relative merits of alternative VTOL air transportation concepts.

Smith, K. R., Jr.; Belina, F. W.

1974-01-01

36

Ground facilities for a VTOL intercity air transportation system  

E-print Network

Introduction: This study covers the design of ground facilities, or metroports, for a future form of short haul intercity air transportation, the VTOL Airbus system as described by previous M.I.T. Flight Transportation ...

Allen Edward

1970-01-01

37

The personal aircraft: Status and issues  

NASA Technical Reports Server (NTRS)

Paper summarizes the status of personal air transportation with emphasis upon VTOL and converticar capability. The former obviates the need for airport operations for personal aircraft whereas the latter provides both ground and air capability in the same vehicle. Fully automatic operation, ATC and navigation is stressed along with consideration of acoustic, environmental and cost issues.

Anders, Scott G.; Asbury, Scott C.; Brentner, Kenneth S.; Bushnell, Dennis M.; Glass, Christopher E.; Hodges, William T.; Morris, Shelby J., Jr.; Scott, Michael A.

1994-01-01

38

Modern digital flight control system design for VTOL aircraft  

NASA Technical Reports Server (NTRS)

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

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

1979-01-01

39

Turbofan blade stresses induced by the flow distortion of a VTOL inlet at high angles of attack  

NASA Technical Reports Server (NTRS)

A 51-cm-diameter turbofan with a tilt-nacelle VTOL inlet was tested in the Lewis Research Center's 9- by 15-Ft Low Speed Wind Tunnel at velocities up to 72 m/s and angles of attack up to 120 deg. Fan-blade vibratory stress levels were investigated over a full aircraft operating range. These stresses were due to inlet air flow distortion resulting from (1) internal flow separation in the inlet, and (2) ingestion of the exterior nacelle wake. Stress levels are presented, along with an estimated safe operating envelope, based on infinite blade fatigue life.

Williams, R. C.; Diedrich, J. H.; Shaw, R. J.

1983-01-01

40

Engine selection for transport and combat aircraft.  

NASA Technical Reports Server (NTRS)

Review of the procedures used to select engines for transport and combat aircraft by illustrating the procedures for a long haul CTOL transport, a short haul VTOL transport, a long range SST, and a fighter aircraft. For the CTOL transport, it is shown that advances in noise technology and advanced turbine cooling technology will greatly reduce the airplane performance penalties associated with achieving low noise goals. A remote lift fan powered by a turbofan air generator is considered for the VTOL aircraft. In this case, the lift fan pressure ratio which maximizes payload also comes closest to meeting the noise goal. High turbine temperature in three different engines is considered for the SST. Without noise constraints it leads to an appreciable drop in DOC, but with noise constraints the reduction in DOC is very modest. For the fighter aircraft it is shown how specific excess power requirements play the same role in engine selection as noise constraints for commercial airplanes.

Dugan, J. F., Jr.

1972-01-01

41

Navigation and guidance requirements for commercial VTOL operations  

NASA Technical Reports Server (NTRS)

The NASA Langley Research Center (LaRC) has undertaken a research program to develop the navigation, guidance, control, and flight management technology base needed by Government and industry in establishing systems design concepts and operating procedures for VTOL short-haul transportation systems in the 1980s time period. The VALT (VTOL Automatic Landing Technology) Program encompasses the investigation of operating systems and piloting techniques associated with VTOL operations under all-weather conditions from downtown vertiports; the definition of terminal air traffic and airspace requirements; and the development of avionics including navigation, guidance, controls, and displays for automated takeoff, cruise, and landing operations. The program includes requirements analyses, design studies, systems development, ground simulation, and flight validation efforts.

Hoffman, W. C.; Hollister, W. M.; Howell, J. D.

1974-01-01

42

Lateral control system design for VTOL landing on a DD963 in high sea states. M.S. Thesis  

NASA Technical Reports Server (NTRS)

The problem of designing lateral control systems for the safe landing of VTOL aircraft on small ships is addressed. A ship model is derived. The issues of estimation and prediction of ship motions are discussed, using optimal linear linear estimation techniques. The roll motion is the most important of the lateral motions, and it is found that it can be predicted for up to 10 seconds in perfect conditions. The automatic landing of the VTOL aircraft is considered, and a lateral controller, defined as a ship motion tracker, is designed, using optimal control techniqes. The tradeoffs between the tracking errors and the control authority are obtained. The important couplings between the lateral motions and controls are demonstrated, and it is shown that the adverse couplings between the sway and the roll motion at the landing pad are significant constraints in the tracking of the lateral ship motions. The robustness of the control system, including the optimal estimator, is studied, using the singular values analysis. Through a robustification procedure, a robust control system is obtained, and the usefulness of the singular values to define stability margins that take into account general types of unstructured modelling errors is demonstrated. The minimal destabilizing perturbations indicated by the singular values analysis are interpreted and related to the multivariable Nyquist diagrams.

Bodson, M.

1982-01-01

43

Digital adaptive controllers for VTOL vehicles. Volume 2: Software documentation  

NASA Technical Reports Server (NTRS)

The VTOL approach and landing test (VALT) adaptive software is documented. Two self-adaptive algorithms, one based on an implicit model reference design and the other on an explicit parameter estimation technique were evaluated. The organization of the software, user options, and a nominal set of input data are presented along with a flow chart and program listing of each algorithm.

Hartmann, G. L.; Stein, G.; Pratt, S. G.

1979-01-01

44

Design and Testing of VTOL UAV Cyclocopter with 4 Rotors  

Microsoft Academic Search

A cyclocopter propelled by the cycloidal blade system is a new concept of VTOL vehicle which has excellent hovering characteristics when compared with helicopters. The cycloidal blade system, which can be described as a horizontal rotary wing, offers powerful thrust levels, and a unique ability to change the direction of the thrust almost instantly. In this study, an unmanned-scaled cyclocopter

In Seong Hwang; Chang Sup; Seung Yong Hwang; Choong Hee Lee; Yun Han Lee

45

A spiral guidance approach concept for commercial VTOL operations  

NASA Technical Reports Server (NTRS)

The results of an investigation of the guidance and navigation requirements for VTOL spiral descents in the presence of winds are reported. Models were developed to describe the spiral maneuver and candidate guidance laws were formulated and analyzed. An important element of the guidance scheme is a unique wind estimator which uses the perturbations in bank angle and heading to improve the knowledge of the winds. Finally, recommendations for additional research, including a flight program, were outlined to evaluate the spiral guidance concept.

Hoffman, W. C.; Hollister, W. M.

1975-01-01

46

Unsteady three-dimensional simulation of VTOL upwash fountain turbulence  

NASA Technical Reports Server (NTRS)

Numerical simulations of a planar turbulent wall jet and a planar VTOL upwash fountain were performed. These are three dimensional simulations which resolve large scale unsteady motions in the flows. The wall jet simulation shows good agreement with experimental data and is presented to verify the simulation methodology. Simulation of the upwash fountain predicts elevated shear stress and a half velocity width spreading rate of 33% which agrees well with experiment. Turbulence mechanisms which contribute to the enhanced spreading rate are examined.

Childs, Robert E.; Nixon, David

1987-01-01

47

Study for conceptual design of VEO, VTOL exhaust nozzle  

NASA Technical Reports Server (NTRS)

Design requirements for a VEO Wing V/STOL exhaust nozzle with a two dimensional shape and having the capability for upper surface blowing, spanwise blowing, and 90 deg turning of the exhaust flow for VTOL were established. A preliminary design of the nozzle that identified the actuation scheme, key dimensions, the flowpath, and the recommended materials were prepared. The airplane characteristics resulting from integrating the study nozzle were established.

Bittrick, W. C.

1980-01-01

48

Concentric circles based simple optical landing aid for vertical takeoff and landing aircrafts  

NASA Astrophysics Data System (ADS)

Vertical takeoff and landing (VTOL) aircrafts such as helicopters and drones, add a flexible degree of operation to airborne vehicles. In order to operate these devices in low light situations, where it is difficult to determine slope of the landing surface, a lightweight and standalone device is proposed here. This small optical device can be easily integrated into current VTOL systems. An optical projector consisting of low power, light weight, solid state laser along with minimal optics is utilized to illuminate the landing surface with donut shaped circles and coaxial centralized dot. This device can placed anywhere on the aircraft and a properly placed fiber system can be used to illuminate the surface beneath the bottom of the VTOL aircraft in a fashion that during operation, when the aircraft is parallel to the landing surface, the radius between the central dot and outer ring(s) are equidistant for the entire circumference; however, when there the landing surface of the VTOL aircraft is not parallel to the landing strip, the radial distance between two opposite sides of the circle and central dot will be unequal. The larger this distortion, the greater the difference will be between the opposite sides of the circle. Visual confirmation or other optical devices can be used to determine relative alignment of the projector output allowing the pilot to make proper adjustments as they approach the landing surface to ensure safe landings. Simulated and experimental results from a prototype optical projector are presented here.

Murshid, Syed H.; Enaya, Rayan; Lovell, Gregory L.

2014-09-01

49

Simulation evaluation of two VTOL control/display systems in IMC approach and shipboard landing  

NASA Technical Reports Server (NTRS)

Two control/display systems, which differed in overall complexity but were both designed for VTOL flight operations to and from small ships in instrument meteorological conditions (IMC), were tested using the Ames Flight Simulator for Advanced Aircraft (FSAA). Both systems have attitude command in transition and horizontal-velocity command in hover; the more complex system also has longitudinal-acceleration and flightpath-angle command in transition, and vertical-velocity command in hover. The most important overall distinction between the two systems for the viewpoint of implementation is that in one - the more complex - engine power and nozzle position are operated indirectly through flight controllers, whereas in the other they are operated directly by the pilot. Simulated landings were made on a moving model of a DD 963 Spruance-class destroyer. Acceptable transitions can be performed in turbulence of 3 m/sec rms using either system. Acceptable landings up to sea state 6 can be performed using the more complex system, and up to sea state 5 using the other system.

Merrick, V. K.

1984-01-01

50

Stability and control of VTOL capable airships in hovering flight  

NASA Technical Reports Server (NTRS)

The stability and control characteristics of an airship equipped with lifting rotors to provide a modest VTOL capability are discussed. The rotors are used for control and maneuvering in near-hovering flight. Configurations with two, three, and four lifting rotors are examined and compared with respect to control capabilities and dynamic response characteristics. Linearized models of the dynamics are employed for this study. A new approach to the prediction of rotor derivatives for operation near zero thrust in hover is presented. It is found that all three configurations have similar control and response characteristics. The responses are characterized by long time constants and low levels of angular damping.

Curtiss, H. C., Jr.; Sumantran, V.

1985-01-01

51

Strapdown system redundancy management flight demonstration. [vertical takeoff and landing aircraft  

NASA Technical Reports Server (NTRS)

The suitability of strapdown inertial systems in providing highly reliable short-term navigation for vertical take-off and landing (VTOL) aircraft operating in an intra-urban setting under all-weather conditions was assessed. A preliminary design configuration of a skewed sensor inertial reference system employing a redundancy management concept to achieve fail-operational, fail-operational performance, was developed.

1978-01-01

52

Agile turnaround using post-stall maneuvers for tail-sitter VTOL UAVs  

Microsoft Academic Search

Miniature vertical take-off and landing unmanned aerial vehicles (VTOL UAVs) make various missions possible alone such as surveillance in partially-destroyed building and at broad hazard area where many obstacle exist. In such missions, agile turnaround using post-stall maneuvers is useful to avoid obstacles. This paper discusses agile turnaround strategies utilizing post-stall maneuvers for tail-sitter VTOL UAVs. Two agile turn strategies

Takaaki Matsumoto; Atsushi Konno; Ren Suzuki; Atsushi Oosedo; Kenta Go; Masaru Uchiyama

2010-01-01

53

A look at V/STOL for business aircraft.  

NASA Technical Reports Server (NTRS)

Attempt to ascertain the economic viability of the V/STOL capability for business aircraft and the manner in which this viability depends on the aircraft concept. A cost-benefit analysis is presented which indicates that a VTOL business aircraft would be more viable economically than a contemporary turbine-powered business aircraft. The combination of traveler's time value and trip distance for which each aircraft dominates is shown. The significance of disk loading in V/STOL concept application is discussed, and preliminary design configuration studies for three different business-aircraft-sized V/STOLs, using three concepts covering a range of disk loading, are presented as examples. Finally, a discussion of operational aspects of interest to future users of V/STOL business aircraft is presented which centers around the requirements for routine IFR terminal-area operations.

Feistel, T. W.; Stewart, E. C.; Gerdes, R. M.; Smith, K. R., Jr.

1972-01-01

54

Study of aircraft in intraurban transportation systems, volume 3  

NASA Technical Reports Server (NTRS)

An investigation of three aircraft concepts, deflected slipstream STOL, helicopter VTOL, and fixed wing STOL, is presented. An attempt was made to determine the best concept for the intraurban transportation system. Desirability of the concept was based on ease of maintenance, development timing, reliability, operating costs, and the noise produced. Indications are that the deflected slipstream STOL is best suited for intraurban transportation. Tables and graphs are included.

Stout, E. G.; Kesling, P. H.; Matteson, D. E.; Sherwood, D. E.; Tuck, W. R., Jr.; Vaughn, L. A.

1971-01-01

55

Design of a Long Endurance Titan VTOL Vehicle  

NASA Technical Reports Server (NTRS)

Saturn s moon Titan promises insight into many key scientific questions, many of which can be investigated only by in situ exploration of the surface and atmosphere of the moon. This research presents a vertical takeoff and landing (VTOL) vehicle designed to conduct a scientific investigation of Titan s atmosphere, clouds, haze, surface, and any possible oceans. In this investigation, multiple options for vertical takeoff and horizontal mobility were considered. A helicopter was baselined because of its many advantages over other types of vehicles, namely access to hazardous terrain and the ability to perform low speed aerial surveys. Using a nuclear power source and the atmosphere of Titan, a turbo expander cycle produces the 1.9 kW required by the vehicle for flight and operations, allowing it to sustain a long range, long duration mission that could traverse the majority of Titan. Such a power source could increase the lifespan and quality of science for planetary aerial flight to an extent that the limiting factor for the mission life is not available power but the life of the mechanical parts. Therefore, the mission could potentially last for years. This design is the first to investigate the implications of this potentially revolutionary technology on a Titan aerial vehicle.

Prakash, Ravi; Braun, Robert D.; Colby, Luke S.; Francis, Scott R.; Guenduez, Mustafa E.; Flaherty, Kevin W.; Lafleur, Jarret M.; Wright, Henry S.

2006-01-01

56

Engine selection for transport and combat aircraft  

NASA Technical Reports Server (NTRS)

The procedures that are used to select engines for transport and combat aircraft are discussed. In general, the problem is to select the engine parameters including engine size in such a way that all constraints are satisfied and airplane performance is maximized. This is done for four different classes of aircraft: (1) a long haul conventional takeoff and landing (CTOL) transport, (2) a short haul vertical takeoff and landing (VTOL) transport, (3) a long range supersonic transport (SST), and (4) a fighter aircraft. For the commercial airplanes the critical constraints have to do with noise while for the fighter, maneuverability requirements define the engine. Generally, the resultant airplane performance (range or payload) is far less than that achievable without these constraints and would suffer more if nonoptimum engines were selected.

Dugan, J. F., Jr.

1972-01-01

57

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

58

Effect of crossflow velocity on the generation of lift fan jet noise in VTOL aircraft  

NASA Technical Reports Server (NTRS)

Analytical studies based on a turbulent mixing noise prediction technique indicate that jet noise power levels are increased when a jet is situated in a crossflow. V/STOL model transport acoustic test data obtained in the NASA Ames 40 ft. x 80 ft. wind tunnel confirmed this jet noise power level increase due to crossflow. Increases up to 6 db at a Strouhal number of 2.5 and crossflow velocity to jet velocity ratio of 0.58 were observed. The power level increases observed in the experimental data confirm the predicted power level increases.

Stimpert, D. L.; Fogg, R. G.

1973-01-01

59

A different look at output tracking: control of a vtol aircraft  

Microsoft Academic Search

In this paper we propose a scheme for output tracking of nonminimum phase flat systems. The technique, which is applicable even in the minimum phase case, uses an inverse trajectory for feedforward which is stabilized by a state tracker built using the flat output. In contrast to approximate-linearization based control [Hauser, J., S. Sastry and G. Meyer (1992). Nonlinear control

Philippe Martin; Santosh Devasia; Brad Paden

1996-01-01

60

The effect of engine component noise on V/STOL aircraft noise contours  

NASA Technical Reports Server (NTRS)

An analytical study of fly-over noise using noise contours to show the effects of varying airplane and path parameters. The method of approach was to synthesize engine component noise spectra and exercise these components along given flight paths to measure the individual and total fly-over effect as a function of noise footprint area. The study was carried out in two phases. Phase 1 utilized a research type aircraft and Phase 2 used an advanced VTOL aircraft. The effect of cross flow was considered for both inlet and exhaust sections of the engine.

Fogg, R. G.

1974-01-01

61

Study of aircraft in intraurban transportation systems, volume 1  

NASA Technical Reports Server (NTRS)

An analysis of an effective short range, high density computer transportation system for intraurban systems is presented. The seven county Detroit, Michigan, metropolitan area, was chosen as the scenario for the analysis. The study consisted of an analysis and forecast of the Detroit market through 1985, a parametric analysis of appropriate short haul aircraft concepts and associated ground systems, and a preliminary overall economic analysis of a simplified total system designed to evaluate the candidate vehicles and select the most promising VTOL and STOL aircraft. Data are also included on the impact of advanced technology on the system, the sensitivity of mission performance to changes in aircraft characteristics and system operations, and identification of key problem areas that may be improved by additional research. The approach, logic, and computer models used are adaptable to other intraurban or interurban areas.

Stout, E. G.; Kesling, P. H.; Matteson, H. C.; Sherwood, D. E.; Tuck, W. R., Jr.; Vaughn, L. A.

1971-01-01

62

The Advantages, Potentials and Safety of VTOL Suborbital Space Tourism Operations  

NASA Astrophysics Data System (ADS)

Suborbital space tourism offers short-time zero gravity and Earth view from space to its customers, and a package that can offer the longest duration of zero- gravity and the most exciting Earth view from space to its customer can be considered a better one than the others. To increase the duration of zero gravity time involves the design and engineering of the suborbital vehicles, but to improve the view of Earth from space aboard a suborbital vehicle, involves more than just the design and engineering of the vehicle, but more on the location of where the vehicle operates. So far, most of the proposed operations of suborbital space tourism vehicles involve a flight to above 80km and less than 120km and taking-off and landing at the same location. Therefore, the operational location of the suborbital vehicle clearly determines the view of earth from space that will be available to its passengers. The proposed operational locations or spaceports usually are existing airports such as the airport at Curacao Island in the Caribbean or spaceport specially built at locations with economic interests such as Spaceport America in New Mexico or an airport that is going to be built, such as SpaceportSEA in Selangor, Malaysia. Suborbital vehicles operating from these spaceports can only offer limited views of Earth from space which is only few thousand kilometers of land or sea around their spaceports, and a clear view of only few hundred kilometers of land or sea directly below them, even though the views can be enhanced by the application of optical devices. Therefore, the view of some exotic locations such as a colorful coral reef, and phenomena such as a smoking volcano on Earth which may be very exciting when viewed from space will not be available on these suborbital tourism packages. The only possible way for the passengers of a suborbital vehicle to view such exotic locations and phenomena is by flying above or near them, and since it will not be economic and will be more risky for a suborbital vehicle to fly above such objects after taking off from a spaceport far away from the object, and later returning to the spaceport, the way to go is to have the operation of the suborbital vehicle near the exotic locations. Unfortunately, some exotic locations such as a tropical archipelago in the middle of a clear blue ocean or a permanent icecap on a mountain range with variety of vegetation around it due to differences in height may not have suitable runway to function as spaceport, and for such reason, VTOL (vertical take-off and landing) capability for suborbital tourism vehicle may be worth considered. VTOL suborbital space tourism vehicle may not operate from a remote uneconomical location even though the location is near an exotic viewing target, but such vehicle may operate from a luxury super yacht that can sail to exotic locations around the world, and during the journey, the passengers can be trained and prepared for the flight of their life. Such is an advantage and potential of VTOL suborbital space tourism vehicle, but VTOL operation can be more complex than a conventional operation and therefore will increase the risk of operation, and for this reason the safety issue for such operation is very significant. This paper explores and discusses some advantages and potentials of VTOL suborbital space tourism operations and safety issues related to them. It also describes a couple of proposed concepts of VTOL suborbital tourism vehicles and potential exotic locations on Earth to be viewed from such vehicles.

Ridzuan Zakaria, N.; Nasrun, N.; Abu, J.; Jusoh, A.; Azim, L.; Said, A.; Ishak, S.; Rafidi Zakaria, N.

2012-01-01

63

A piloted simulation study of the effects of controller force gradient in VTOL hovering flight  

NASA Technical Reports Server (NTRS)

A study of the effect of control force gradient on the VTOL visual hovering task was conducted on the NASA-Ames Research Center Six-Degree-of-Freedom Motion Simulator. Lateral control force-gradient characteristics were evaluated in combination with three different types of stabilization systems: An unstabilized (acceleration) system, a rate-stabilized system, and two attitude-stabilized systems. The effects of gust disturbances were included in the control force evaluation for the attitude systems. A force gradient of 1.0 lb/in was within the optimum range for all control systems and conditions evaluated in this study.

Fry, E. B.; Gerdes, R. M.; Schroers, L. G.

1973-01-01

64

Simulation study of two VTOL control/display systems in IMC approach and landing  

NASA Technical Reports Server (NTRS)

Both systems had full attitude command; the more complex system (Type 1) also had translational velocity command. The systems were applied to existing models of a VTOL lift-fan transport and the AV-8A Harrier. Simulated landings were made on a model of a DD963 Spruance-class destroyer. It was concluded that acceptable transitions and vertical landings can be performed, using the Type 1 system, in free-air turbulence up to 2.5 m/sec and sea state 6 and, using the Type 2 system, in free-air turbulence up to 1.5 m/sec and sea state 4.

Merrick, V. K.

1981-01-01

65

The Unmanned Mission Avionics Test Heliciopter - a Flexible and Versatile Vtol-Uas Experimental System  

NASA Astrophysics Data System (ADS)

civil customers. These applications cover a wide spectrum from R&D programs for the military customer to special services for the civil customer. This paper focuses on the technical conversion of a commercially available VTOL-UAS to ESG's Unmanned Mission Avionics Test Helicopter (UMAT), its concept and operational capabilities. At the end of the paper, the current integration of a radar sensor is described as an example of the UMATs flexibility. The radar sensor is developed by the Fraunhofer Institute for High Frequency Physics and Radar Techniques (FHR). It is integrated by ESG together with the industrial partner SWISS UAV.

Schulz, H.-W., , Dr.

2011-09-01

66

Influence of Tip Clearance and Inlet Flow Distortion on Ducted Fan Performance in VTOL UAVs Graduate Research Assistant  

E-print Network

1 Influence of Tip Clearance and Inlet Flow Distortion on Ducted Fan Performance in VTOL UAVs Ali in these applications are distortion of inlet flow due to forward flight and tip leakage related problems in hover are dramatically increased in forward flight due to inlet lip separation and inlet flow distortion. For a better

Camci, Cengiz

67

Preliminary Assessment of Using Gelled and Hybrid Propellant Propulsion for VTOL/SSTO Launch Systems  

NASA Technical Reports Server (NTRS)

A novel, reusable, Vertical-Takeoff-and-Vertical-Takeoff-and-Landing, Single-Stage-to-Orbit (VTOL/SSTO) launch system concept, named AUGMENT-SSTO, is presented in this paper to help quantify the advantages of employing gelled and hybrid propellant propulsion system options for such applications. The launch vehicle system concept considered uses a highly coupled, main high performance liquid oxygen/liquid hydrogen (LO2/LH2) propulsion system, that is used only for launch, while a gelled or hybrid propellant propulsion system auxiliary propulsion system is used during final orbit insertion, major orbit maneuvering, and landing propulsive burn phases of flight. Using a gelled or hybrid propellant propulsion system for major orbit maneuver burns and landing has many advantages over conventional VTOL/SSTO concepts that use LO2/LH2 propulsion system(s) burns for all phases of flight. The applicability of three gelled propellant systems, O2/H2/Al, O2/RP-1/Al, and NTO/MMH/Al, and a state-of-the-art (SOA) hybrid propulsion system are examined in this study. Additionally, this paper addresses the applicability of a high performance gelled O2/H2 propulsion system to perform the primary, as well as the auxiliary propulsion system functions of the vehicle.

Palaszewski, Bryan; OLeary, Robert; Pelaccio, Dennis G.

1998-01-01

68

Preliminary development of a VTOL unmanned air vehicle for the close-range mission  

NASA Astrophysics Data System (ADS)

The preliminary development of a full-scale Vertical Takeoff and Landing (VTOL) Unmanned Air Vehicle (UAV) for the Close-Range mission was completed at the Naval Postgraduate School (NPS). The vehicle was based on half-scale ducted-fan investigations performed at the UAV Flight Research Lab. The resulting design is a fixed-duct, tail-sitter UAV with a canard-configured horizontal stabilizer. Major airframe components are used from previous UAV's and include the wings from a U.S. Army Aquila and the ducted fan from the U.S. Marine Corps AROD. Accomplishments include: (1) the design and fabrication of a carry-through spar, and (2) the design and construction of an engine test stand. The through spar was designed using finite element analysis and constructed from composite materials. The purpose of the test stand is to measure torque, horsepower, and thrust of an entire ducted fan or an individual engine. Completion of this thesis will pave the way for future NPS research into the growing interest in VTOL UAV technology.

Kress, Gregory A.

1992-09-01

69

Flight test evaluation of a digital controller used in a VTOL automatic approach and landing system  

NASA Technical Reports Server (NTRS)

As part of the NASA Langley Research Center's effort to develop technology for VTOL operation in the air transportation system in the late 1980's and beyond, research has been conducted aimed at developing digital controller design procedures. This paper describes the verification of one design procedure by the flight evaluation of an advanced digital control algorithm. The control algorithm, operating at 10 iterations per second, follows step guidance commands with zero steady state error and thus provides an autotrim capability for the nonlinear vehicle. Changes in vehicle dynamics are accounted for using a gain scheduling technique. This control algorithm is combined with sensor filters, a trajectory generator, and a closed loop guidance algorithm to form a VTOL autoland system. A CH-47 tandem rotor helicopter which contains a set of sensors, onboard digital flight computers and electro-hydraulic actuators is used in the evaluation. All software, except input-output routines, is coded in FORTRAN using floating point arithmetic and executed in the flight computer. This autoland system is exercised by automatically flying straight-in descending decelerating trajectories typical of VFR manual approaches to a predetermined landing pad.

Downing, D. R.; Bryant, W. H.

1979-01-01

70

Conceptual design studies of 1985 commercial VTOL transports that utilized rotors, Volume 1  

NASA Technical Reports Server (NTRS)

Results of conceptual design studies of commercial rotary wing transport aircraft for the 1985 time period are presented. Two aircraft configurations, a tandem helicopter and a tilt rotor, were designed for a 200 nautical mile short haul mission with an upper limit of 100 passengers. In addition to the baseline aircraft two further designs of each configuration are included to assess the impact of external noise design criteria on the aircraft size, weight, and cost.

Magee, J. P.; Clark, R. D.; Alexander, H. R.

1974-01-01

71

Mystery Aircraft  

NSDL National Science Digital Library

The Federation of American Scientists offers this unique perspective into classified government aircraft, "some of which actually exist, some of which certainly do not, and all of which are fascinating in a way." This site is divided into two main sections. The first provides insight into several aircraft that were initially shrouded in secrecy but have since been revealed to the public. Some examples include the SR-71, the B-2, and the Hyper-X. The second section is devoted to aircraft that may or may not be currently under development or in operation by the US government. The much popularized Aurora is in this section, as well as exotic propulsion aircraft.

72

An experimental study of a jet issuing from a lifting wing. [vertical-horizontal flight transitions in VTOL aircraft  

NASA Technical Reports Server (NTRS)

An experimental program was conducted to determine the behavior of a round turbulent jet issuing from a lifting two-dimensional wing in crossflow. The jet was located at 65% wing chord on an NACA 0021 airfoil fitted with a 30% chord NACA 4415 flap. The flowfield associated with the jet was surveyed extensively with directional pressure probes to determine local velocity vectors and pressures for three different values of lift coefficient at jet effective velocity ratios (square root of the ratio of the jet dynamic pressure to the freestream dynamic pressure) of 4, 6, and 8. Data describing the jet centerline and the path of the contrarotating vortices accompanying the deflected jet are presented and compared with similar data for a round jet issuing from a large flat plate. The spacing and strength of the vortices are calculated using a simple vortex model previously proposed for the flat plate case. The results show that the penetration of the jet and the vortices increases significantly with increasing lift for the range of test parameters covered in the study. The calculated vortex spacing and strength also show an increase with lift.

Mcmahon, H. M.; Antani, D. L.

1979-01-01

73

Studies in tilt rotor VTOL aircraft aeroelasticity, volume 2. Ph.D. Thesis - Case Western Reserve Univ.  

NASA Technical Reports Server (NTRS)

Two methods for natural mode vibration analysis are discussed. The first consists of a direct approach based on a finite element representation of the complete structure as an entity. The mass and stiffness matrices for the complete structure are assembled by properly combining the mass and stiffness matrices of the individual elements into which the structure has been divided. The second approach is that of component mode synthesis. This method is based on the concept of synthesizing the natural modes of the complete structure from modes of conveniently difined substructures, or components, into which the structure has been partitioned. In this way the expedient of reducing the system degrees of freedom, and thus the size of the eigenvalue problem, can be introduced by partial modal synthesis.

Kvaternik, R. G.

1973-01-01

74

Study of the application of an implicit model-following flight controller to lift-fan VTOL aircraft  

NASA Technical Reports Server (NTRS)

An implicit model-following flight controller is proposed. This controller is relatively simple in concept: it provides an input/output relationship that is approximately that of any selected second order system; it provides good gust alleviation; and it is self-trimming. The flight controller was applied to all axes of a comprehensive mathematical model of a lift-fan V/STOL transport. Power management controls and displays were designed to match the various modes of control provided by the flight controller. A piloted simulation was performed using a six degree of freedom simulator. The fixed-operating-point handling qualities throughout the powered lift flight envelope received pilot ratings of 3-1/2 or better. Approaches and vertical landings in IFR zero-zero conditions received pilot ratings varying from 2-1/2 to 4 depending on the type of approach and weather conditions.

Merrick, V. K.

1977-01-01

75

Performance and Flowfield Measurements on a 10-inch Ducted Rotor VTOL UAV  

NASA Technical Reports Server (NTRS)

A ducted fan VTOL UAV with a 10-inch diameter rotor was tested in the US Army 7-by 10-Foot Wind Tunnel. The test conditions covered a range of angle of attack from 0 to 110 degrees to the freestream. The tunnel velocity was varied from 0 (simulating a hover condition) to 128 ft/sec in propeller mode. A six-component internal balance measured the aerodynamic loads for a range of model configurations. including the isolated rotor, the isolated duct, and the full configuration of the duct and rotor. For some conditions, hotwire velocity surveys were conducted along the inner and outer surface of the duct and across the downstream wake. In addition, fluorescent oil flow visualization allowed the flow separation patterns inside and outside of the duct to be mapped for a few test conditions. Two different duct shapes were tested to determine the performance effects of leading edge radius. For each duct, a range of rotor tip gap from 1%R to 4.5%R was tested to determine the performance penalty in hover and axial flight. Measured results are presented in terms of hover performance, hover performance in a crosswind, and high angle of attack performance in propeller mode. In each case, the effects of both tip gap and duct leading edge radius are illustrated using measurements. Some of the hover performance issues were also studied using a simple analytical method, and the results agreed with the measurements.

Martin, Preston; Tung, Chee

2004-01-01

76

Integrated propulsion/energy transfer control systems for lift-fan V/STOL aircraft. [reduction of total propulsion system and control system installation requirements  

NASA Technical Reports Server (NTRS)

An integrated propulsion/control system for lift-fan transport aircraft is described. System behavior from full-scale experimental and piloted simulator investigations are reported. The lift-fan transport is a promising concept for short-to-medium haul civil transportation and for other missions. The lift-fan transport concept features high cruise airspeed, favorable ride qualities, small perceived noise footprints, high utilization, transportation system flexibility, and adaptability to VTOL, V/STOL, or STOL configurations. The lift-fan transport has high direct operating costs in comparison to conventional aircraft, primarily because of propulsion system and aircraft low-speed control system installation requirements. An integrated lift-fan propulsion system/aircraft low-speed control system that reduces total propulsion system and control system installation requirements is discussed.

Deckert, W. H.; Rolls, L. S.

1974-01-01

77

Full-Scale Wind-Tunnel Investigation of the VZ-5 Four-Propeller Deflected-Slipstream VTOL Airplane  

NASA Technical Reports Server (NTRS)

The investigation was conducted to determine the static stability and control characteristics of the VZ-5 VTOL air-plane over the speed range from hovering to forward flight. Force and moment data were taken over a range of angles of attack of 0 to 15 deg and a range of sideslip of +/-10 deg for flap deflections from 0 to 77 deg. The longitudinal stability and trim characteristics were found to be quite unacceptable and it did not seem that they could be corrected with any reasonable modifications to the airplane.

Fink, Marvin P.

1963-01-01

78

Conceptual design studies of 1985 commercial VTOL transports that utilized rotors, Volume 2  

NASA Technical Reports Server (NTRS)

Results of conceptual design studies of tilt rotor and tandem helicopter aircraft for a 200 nautical mile commercial short haul transport mission are presented. The trade study data used in selecting the design point aircraft and technology details necessary to support the design conclusions are included.

Magee, J. P.; Clark, R.; Alexander, H. R.

1974-01-01

79

Aircraft liftmeter  

NASA Technical Reports Server (NTRS)

A display for aiding the pilot of an aircraft in anomalous wind environments is described. Wind velocity components are measured by an instrument, processed by a computer and a vector generator, and then displayed as a vector. The display utilizes the measurements of ground speed and of wind velocity in three mutually perpendicular directions. This display will also show changes in lift of an aircraft.

Millen, E. W. (inventor)

1986-01-01

80

Aircraft disinsection.  

PubMed

Aircraft disinsection has been an international practice since the 1920s, the purpose of which is to protect public health, the environment, agriculture, and livestock by the eradication of disease vectors. Although most nations of the world have discontinued this practice, about 20 continue with this requirement. Aircraft disinsection is sanctioned by international law with the World Health Organization (WHO) publishing general procedural guidelines in the International Health Regulations (IHR). There are currently four acceptable procedures: blocks away, top of descent, on arrival, and residual. A 2% pyrethrum solution, a naturally occurring substance found in the chrysanthemum flower, or several synthetic pyrethroids, are the recommended agents because they are extremely effective insecticides which pose minimal health risks. Although the use of insecticides for aircraft disinsection is controversial, national policies compelling this requirement must be respected. This paper will explore the background of aircraft disinsection, the procedures, the types of agents, and the toxicity. If aircraft disinsection is regulatory policy, it should be done in accordance with WHO procedures. Residual application is probably the most efficacious method. The use of air curtains or plastic strips should be explored as an alternative to the use of chemicals. PMID:16856359

Rayman, Russell B

2006-07-01

81

Aircraft battery  

SciTech Connect

An aircraft battery is described that has a polypropylene casing for receiving the lead plates and acid therein, the casing being configured to fit closely within and be bonded to an aluminum housing and having a thickened base portion with individual cells formed by polypropylene walls to provide improved insulation while maintaining the light weight and the structural integrity of the casing.

Karpal, D.L.

1980-12-02

82

Aircraft Contrails  

NSDL National Science Digital Library

NASA's Earth Observatory "Aircraft Contrails" webpage summarizes the key mechanism, measurements, and predictions of how cirrus clouds produced by contrails contribute to global warming. The page also includes an image showing a large number of contrails produced over the southeastern U. S.

Observatory, Nasa E.

2011-09-15

83

Lift cruise fan V/STOL aircraft conceptual design study T-39 modification. Volume 1: Technical report  

NASA Technical Reports Server (NTRS)

The conversion of two T-39 aircraft into lift cruise fan research and technology vehicles is discussed. The concept is based upon modifying the T-39A (NA265-40) Sabreliner airframe into a V/STOL configuration by incorporating two LCF-459 lift cruise fans and three YJ-97 gas generators. The propulsion concept provides the thrust for horizontal flight or lift for vertical flight by deflection of bifurcated nozzles while maintaining engine out safety throughout the flight envelope. The configuration meets all the study requirements specified for the design with control powers in VTOL and conversion in excess of the requirement making it an excellent vehicle for research and development. The study report consists of two volumes; Volume 1 (Reference a) contains background data detailed description and technical substantiation of the aircraft. Volume 2 includes cost data, scheduling and program planning not addressed in Volume 1.

Elliott, D. W.

1976-01-01

84

Conceptual design study of 1985 commercial VTOL transports that utilize rotors  

NASA Technical Reports Server (NTRS)

Conceptual design studies of pure and compound helicopter commercial short-haul transport aircraft for initial fabrication in 1980 were performed to determine their technical and economic feasibility. One-hundred-passenger configurations were optimized for minimum direct operating cost consistent with producibility and marketability, with emphasis on proper account of mass properties, performance and handling qualities adequacy, and suppression of internal and external noise. The effect of external noise constraints was assessed, in terms of gross weight and direct operating cost, for each aircraft.

Kefford, N. F. K.; Munch, C. L.

1975-01-01

85

Longitudinal Aerodynamic Characteristics of a Four-Propeller Deflected Slipstream VTOL Model Including the Effects of Ground Proximity  

NASA Technical Reports Server (NTRS)

Results are presented of a wind-tunnel investigation of the longitudinal stability, control, and performance characteristics of a model of a four-propeller deflected-slipstream VTOL airplane in the transition speed range. These results indicate that steady level-flight transition and descending flight-path angles up to 7 or 8 deg. out of the region of ground effect can be accomplished without wing stall being encountered. In general, the pitching moments out of ground proximity can be adequately trimmed by programming the stabilizer incidence to increase with increasing flap deflection, except for a relatively large diving moment in the hovering condition. The deflection of the slipstream onto the horizontal tail in proximity of the ground substantially increases the diving moment in hovering, unless the tail is set at a large nosedown incidence.

Kuhn, Richard E.; Grunwald, Kalman J.

1960-01-01

86

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

87

Simulation evaluation of flight controls and display concepts for VTOL shipboard operations  

NASA Technical Reports Server (NTRS)

A ground-based evaluation of several control-system concepts and display formats for use in shipboard landing operations of a V/STOL aircraft (AV-8A Harrier) is reported. The study was conducted in the Vertical Motion Simulator at Ames Research Center. The control systems ranged from a rate-damping SAS to a translational-velocity command system; displays ranged from a head-down presentation of attitude and altitude to two different head-up formats that provided position and velocity information. Results of pilot evaluations of the aircraft's handling qualities, as well as measures of task performance and control power use during landing on a moving deck in visual meteorological condtions, are presented.

Farris, G. G.; Merrick, V. K.; Gerdes, R. M.

1983-01-01

88

Ground-simulation investigations of VTOL airworthiness criteria for terminal-area operations  

NASA Technical Reports Server (NTRS)

Several ground-based simulation experiments undertaken to investigate concerns related to tilt-rotor aircraft airworthiness were conducted. The experiments were conducted on the National Aeronautics and Space Administration (NASA) Ames Research Center's Vertical Motion Simulator, which permits simulation of a wide variety of aircraft with a high degree of fidelity of motion cueing. Variations in conversion/deceleration profile, type of augmentation or automation, level of display assistance, and meteorological conditions were considered in the course of the experiments. Certification pilots from the Federal Aviation Administration (FAA) and the Civil Aviation Authority (CAA) participated, in addition to NASA research pilots. The setup of these experiments on the simulator is summarized, and some of the results highlighted.

Lebacqz, J. V.; Decker, W. A.; Alderete, T. S.; Scott, B. C.; Harper, P. J. G.; Chung, W. W.

1990-01-01

89

Conceptual engineering design studies of 1985-era commercial VTOL and STOL transports that utilize rotors  

NASA Technical Reports Server (NTRS)

Conceptual design studies are summarized of tandem-rotor helicopter and tilt-rotor aircraft for a short haul transport mission in the 1985 time frame. Vertical takeoff designs of both configurations are discussed, and the impact of external noise criteria on the vehicle designs, performance, and costs are shown. A STOL design for the tilt-rotor configuration is reported, and the effect of removing the vertical takeoff design constraints on the design parameters, fuel economy, and operating cost is discussed.

Magee, J. P.; Clark, R. D.; Widdison, C. A.

1975-01-01

90

Aircraft Engines  

NSDL National Science Digital Library

Presented by Florida International University and NASA, this website presents a brief tutorial on the schematics for different car and aircraft engines, their cooling mechanisms, and engine development history. Here, visitors will find information on air-breathing, turboprop, turbofan, prop-fan, and ramjet engines along with handy and clear illustrations of each. This is a useful resource for educators looking for a brief, introductory handout for students in mechanical engineering and aeronautics or for students seeking material to simply illustrate the differences between engine types.

2007-07-16

91

Educating with Aircraft Models  

ERIC Educational Resources Information Center

Described is utilization of aircraft models, model aircraft clubs, and model aircraft magazines to promote student interest in aerospace education. The addresses for clubs and magazines are included. (SL)

Steele, Hobie

1976-01-01

92

Some VTOL head-up display drive-law problems and solutions  

NASA Technical Reports Server (NTRS)

A piloted simulation test was conducted on the Ames Research Center's vertical motion simulator (VMS) in support of the Phase 2A flight test of NASA's V/STOL systems research aircraft (VSRA). During the simulation several problems were found with the head-up display (HUD) symbol drive laws and the flightpath synthesis. These problems and the solutions devised to solve them are described. Most of the resulting HUD drive-law changes were implemented during the simulation and their effectiveness was verified. Subsequently both the HUD symbol drive-law and flightpath-synthesis changes were implemented in the VSRA and tested successfully in the Phase 2A flight tests.

Merrick, Vernon K.

1993-01-01

93

Flight Tests of a 1/6-Scale Model of the Hawker P 1127 Jet VTOL Airplane  

NASA Technical Reports Server (NTRS)

An experimental investigation has been made to determine the dynamic stability and control characteristics of a 1/6-scale flying model of the Hawker P lIP7 jet vertical-take-off-and-landing (VTOL) airplane in hovering and transition flight. The model was powered by a counter-rotating ducted fan driven by compressed-air jets at the tips of the fan blades. In hovering flight the model was controlled by jet-reaction controls which consisted of yaw and pitch jets at the extremities of the fuselage and a roll jet on each wing tip. In forward flight the model was controlled by conventional ailerons and rudder and an all-movable horizontal tail. In hovering flight the model could be flown smoothly and easily, but the roll control was considered too weak for rapid maneuvering or hovering in gusty air. Transitions from hovering to normal forward flight and back to hovering could be made smoothly and consistently and with only moderate changes in longitudinal trim. The model had a static longitudinal instability or pitch-up tendency throughout the transition range, but the rate of divergence in the pitch-up was moderate and the model could be controlled easily provided the angle of attack was not allowed to become too high. In both the transition and normal forward flight conditions the lateral motions of the model were difficult to control at high angles of attack, apparently because of low directional stability at small angles of sideslip. The longitudinal stability of the model in normal forward flight was generally satisfactory, but there was a decided pitch-up tendency for the flap-down condition at high angles of attack. In the VTOL landing approach condition, with the jets directed straight down or slightly forward, the nose-down pitch trim required was greater than in the transitions from hovering to forward flight, but the longitudinal instability was about the same. Take-offs and landings in still air could be made smoothly although there was a slight unfavorable ground effect on lift and a nose-down change in pitch trim near the ground. Short take-offs and landings could be made smoothly and consistently although the model experienced a decided nose-up change in pitching moment as it climbed out of ground effect.

Smith, Charles C., Jr.

1961-01-01

94

Study of VTOL in ground-effect flow field including temperature effect  

NASA Technical Reports Server (NTRS)

Detailed pressure, temperature, and velocity data were obtained for twin-fan configurations in-ground-effect and flow models to aid in predicting pressures and upwash forces on aircraft surfaces were developed. For the basic experiments, 49.5 mm-diameter jets were used, oriented normal to a simulated round plane, with pressurized, heated air providing a jet. The experimental data consisted of: (1) the effect of jet height and temperature on the ground, model, and upwash pressures, and temperatures, (2) the effect of simulated aircraft surfaces on the isolated flow field, (3) the jet-induced forces on a three-dimensional body with various strakes, (4) the effects of non-uniform coannular jets. For the uniform circular jets, temperature was varied from room temperature (24 C) to 232 C. Jet total pressure was varied between 9,300 Pascals and 31,500 Pascals. For the coannular jets, intended to represent turbofan engines, fan temperature was maintained at room temperature while core temperature was varied from room temperature to 437 C. Results are presented.

Hill, W. G.; Jenkins, R. C.; Kalemaris, S. G.; Siclari, M. J.

1982-01-01

95

Aircraft. [Soviet technology  

NASA Technical Reports Server (NTRS)

The physical principles of flight, and the consideration of atmospheric composition and aerodynamic forces in the design and construction of various types of aircraft are discussed. Flight characteristics are described for helicopters, rotary-wing aircraft, short and vertical takeoff aircraft, and tailess or variable geometry wing aircraft. Flow characteristics at various speeds are also discussed.

1977-01-01

96

Aircraft Electric Secondary Power  

NASA Technical Reports Server (NTRS)

Technologies resulted to aircraft power systems and aircraft in which all secondary power is supplied electrically are discussed. A high-voltage dc power generating system for fighter aircraft, permanent magnet motors and generators for aircraft, lightweight transformers, and the installation of electric generators on turbine engines are among the topics discussed.

1983-01-01

97

The effect of wind tunnel wall interference on the performance of a fan-in-wing VTOL model  

NASA Technical Reports Server (NTRS)

A fan-in-wing model with a 1.07-meter span was tested in seven different test sections with cross-sectional areas ranging from 2.2 sq meters to 265 sq meters. The data from the different test sections are compared both with and without correction for wall interference. The results demonstrate that extreme care must be used in interpreting uncorrected VTOL data since the wall interference may be so large as to invalidate even trends in the data. The wall interference is particularly large at the tail, a result which is in agreement with recently published comparisons of flight and large scale wind tunnel data for a propeller-driven deflected-slipstream configuration. The data verify the wall-interference theory even under conditions of extreme interference. A method yields reasonable estimates for the onset of Rae's minimum-speed limit. The rules for choosing model sizes to produce negligible wall effects are considerably in error and permit the use of excessively large models.

Heyson, H. H.

1974-01-01

98

Simulated Rotor Wake Interactions Resulting from Civil Tiltrotor Aircraft Operations Near Vertiport Terminals  

NASA Technical Reports Server (NTRS)

A mid-fidelity computational fluid dynamics tool called RotCFD - specifically developed to aid in rotorcraft conceptual design efforts - has been applied to the study of rotor wake interactions of civil tiltrotor aircraft in the immediate vicinity of vertiport/airport ground infrastructure. This issue has grown in importance as previous NASA studies have suggested that civil tiltrotor aircraft can potentially have a significant impact on commercial transport aviation. Current NASA reference designs for such civil tiltrotor aircraft are focused on a size category of 90-120 passengers. Notional concepts of operations include simultaneous non-interfering flight into and out of congested airports having vertiports, that is, prepared VTOL takeoff and landing zones, or underutilized short runways for STOL operation. Such large gross-weight vehicles will be generating very high induced velocities. Inevitably, the interaction of the rotor wake with ground infrastructure such as terminals/jetways must be considered both from an operational as well as design perspective.

Young, Larry A.; Rajagopalan, Ganesh

2013-01-01

99

AIRCRAFT DEPAINTING TECHNOLOGY  

EPA Science Inventory

Chemical paint strippers historically used for aircraft contained toxic and hazardous components; aircraft depainting operations are a major source of hazardous waste generation in DOD. Federal and state agencies have begun to restrict using these hazardous materials and Governme...

100

Investigation of application of two-degree-of-freedom dry tuned-gimbal gyroscopes to strapdown navigation systems. [for use in VTOL aircraft  

NASA Technical Reports Server (NTRS)

The work is described which was accomplished during the investigation of the application of dry-tuned gimbal gyroscopes to strapdown navigation systems. A conventional strapdown configuration, employing analog electronics in conjunction with digital attitude and navigation computation, was examined using various levels of redundancy and both orthogonal and nonorthogonal sensor orientations. It is concluded that the cost and reliability performance constraints which had been established could not be met simultaneously with such a system. This conclusion led to the examination of an alternative system configuration which utilizes an essentially new strapdown system concept. This system employs all-digital signal processing in conjunction with the newly-developed large scale integration (LSI) electronic packaging techniques and a new two-degree-of-freedom dry tuned-gimbal instrument which is capable of providing both angular rate and acceleration information. Such a system is capable of exceeding the established performance goals.

1974-01-01

101

Aircraft landing gear systems  

NASA Technical Reports Server (NTRS)

Topics presented include the laboratory simulation of landing gear pitch-plane dynamics, a summary of recent aircraft/ground vehicle friction measurement tests, some recent aircraft tire thermal studies, and an evaluation of critical speeds in high-speed aircraft. Also presented are a review of NASA antiskid braking research, titanium matrix composite landing gear development, the current methods and perspective of aircraft flotation analysis, the flow rate and trajectory of water spray produced by an aircraft tire, and spin-up studies of the Space Shuttle Orbiter main gear tire.

Tanner, John A. (editor)

1990-01-01

102

Small transport aircraft technology  

NASA Technical Reports Server (NTRS)

Information on commuter airline trends and aircraft developments is provided to upgrade the preliminary findings of a NASA-formed small transport aircraft technology (STAT) team, established to determine whether the agency's research and development programs could help commuter aircraft manufacturers solve technical problems related to passenger acceptance and use of 19- to 50-passenger aircraft. The results and conclusions of the full set of completed STAT studies are presented. These studies were performed by five airplane manufacturers, five engine manufacturers, and two propeller manufacturers. Those portions of NASA's overall aeronautics research and development programs which are applicable to commuter aircraft design are summarized. Areas of technology that might beneficially be expanded or initiated to aid the US commuter aircraft manufacturers in the evolution of improved aircraft for the market are suggested.

Williams, L. J.

1983-01-01

103

Raptors and aircraft  

USGS Publications Warehouse

Less than 5% of all bird strikes of aircraft are by raptor species, but damage to airframe structure or jet engine dysfunction are likely consequences. Beneficial aircraft-raptor interactions include the use of raptor species to frighten unwanted birds from airport areas and the use of aircraft to census raptor species. Many interactions, however, modify the raptor?s immediate behavior and some may decrease reproduction of sensitive species. Raptors may respond to aircraft stimuli by exhibiting alarm, increased heart rate, flushing or fleeing and occasionally by directly attacking intruding aircraft. To date, most studies reveal that raptor responses to aircraft are brief and do not limit reproduction; however, additional study is needed.

Smith, D.G.; Ellis, D.H.; Johnson, T.H.

1988-01-01

104

Hypersonic aircraft design  

NASA Technical Reports Server (NTRS)

A hypersonic aircraft is designed which uses scramjets to accelerate from Mach 6 to Mach 10 and sustain that speed for two minutes. Different propulsion systems were considered and it was decided that the aircraft would use one full scale turbofan-ramjet. Two solid rocket boosters were added to save fuel and help the aircraft pass through the transonic region. After considering aerodynamics, aircraft design, stability and control, cooling systems, mission profile, and landing systems, a conventional aircraft configuration was chosen over that of a waverider. The conventional design was chosen due to its landing characteristics and the relative expense compared to the waverider. Fuel requirements and the integration of the engine systems and their inlets are also taken into consideration in the final design. A hypersonic aircraft was designed which uses scramjets to accelerate from Mach 6 to Mach 10 and sustain that speed for two minutes. Different propulsion systems were considered and a full scale turbofan-ramjet was chosen. Two solid rocket boosters were added to save fuel and help the aircraft pass through the transonic reqion. After the aerodynamics, aircraft design, stability and control, cooling systems, mission profile, landing systems, and their physical interactions were considered, a conventional aircraft configuration was chosen over that of a waverider. The conventional design was chosen due to its landing characteristics and the relative expense compared to the waverider. Fuel requirements and the integration of the engine systems and their inlets were also considered in the designing process.

Alkamhawi, Hani; Greiner, Tom; Fuerst, Gerry; Luich, Shawn; Stonebraker, Bob; Wray, Todd

1990-01-01

105

Aircraft fire safety research  

NASA Technical Reports Server (NTRS)

During the past 15 years, very significant progress has been made toward enhancing aircraft fire safety in both normal and hostile (combat) operational environments. Most of the major aspects of the aircraft fire safety problem are touched upon here. The technology of aircraft fire protection, although not directly applicable in all cases to spacecraft fire scenarios, nevertheless does provide a solid foundation to build upon. This is particularly true of the extensive research and testing pertaining to aircraft interior fire safety and to onboard inert gas generation systems, both of which are still active areas of investigation.

Botteri, Benito P.

1987-01-01

106

Interactive dynamic aircraft scheduling  

E-print Network

Introducing recent advances in computer technology to improve aircraft scheduling is investigated. Incorporating interactive graphics, modern database manipulation techniques, and decision support algorithms, the computer ...

Deckwitz, Thomas Anthony

1984-01-01

107

Fan and wing force data from wind tunnel investigation of a 0.38 meter (15 inch) diameter VTOL model lift fan installed in a two dimensional wing  

NASA Technical Reports Server (NTRS)

Test data are presented for a 38-cm (15-in.) diameter, 1.28 pressure ratio model VTOL lift fan installed in a two-dimensional wing and tested in a 2.74-by 4.58-meter (9-by 15-ft)V/STOL wind tunnel. Tests were run with and without exit louvers over a wide range of crossflow velocities and wing angle of attack. Tests were also performed with annular-inlet vanes, inlet bell-mouth surface disconuities, and fences to induce fan windmilling. Data are presented on the axial force of the fan assembly and overall wing forces and moments as measured on force balances for various static and crossflow test conditions. Midspan wing surface pressure coefficient data are also given.

Yuska, J. A.; Diedrich, J. H.

1972-01-01

108

General Aviation Aircraft Reliability Study  

NASA Technical Reports Server (NTRS)

This reliability study was performed in order to provide the aviation community with an estimate of Complex General Aviation (GA) Aircraft System reliability. To successfully improve the safety and reliability for the next generation of GA aircraft, a study of current GA aircraft attributes was prudent. This was accomplished by benchmarking the reliability of operational Complex GA Aircraft Systems. Specifically, Complex GA Aircraft System reliability was estimated using data obtained from the logbooks of a random sample of the Complex GA Aircraft population.

Pettit, Duane; Turnbull, Andrew; Roelant, Henk A. (Technical Monitor)

2001-01-01

109

Commercial aircraft wake vortices  

Microsoft Academic Search

This paper discusses the problem of wake vortices shed by commercial aircraft. It presents a consolidated European view on the current status of knowledge of the nature and characteristics of aircraft wakes and of technical and operational procedures of minimizing and predicting the vortex strength and avoiding wake encounters.Methodological aspects of data evaluation and interpretation, like the description of wake

Thomas Gerz; Frank Holzäpfel; Denis Darracq

2002-01-01

110

Commercial aircraft wake vortices  

Microsoft Academic Search

This paper discusses the problem of wake vortices shed by commercial aircraft. It presents a consolidated European view on the current status of knowledge of the nature and characteristics of aircraft wakes and of technical and operational procedures of minimizing and predicting the vortex strength and avoiding wake encounters. Methodological aspects of data evaluation and interpretation, like the description of

Thomas Gerza; Frank Holz

111

Aircraft Circuit Breakers  

Microsoft Academic Search

Airplane circuit breakers are recognized as important units in the electrical systems of military aircraft. The design of such circuit breakers can be combined with switching and contactor functions. This makes possible the use of welldeveloped switch and contactor structures. The design of such circuit breakers must provide for operation under the very exacting requirements of military aircraft service. The

C. W. Kuhn

1943-01-01

112

Lightning protection of aircraft  

NASA Technical Reports Server (NTRS)

The current knowledge concerning potential lightning effects on aircraft and the means that are available to designers and operators to protect against these effects are summarized. The increased use of nonmetallic materials in the structure of aircraft and the constant trend toward using electronic equipment to handle flight-critical control and navigation functions have served as impetus for this study.

Fisher, F. A.; Plumer, J. A.

1977-01-01

113

Lightning protection for aircraft  

NASA Technical Reports Server (NTRS)

Reference book summarizes current knowledge concerning potential lightning effects on aircraft and means available to designers and operators to protect against effects. Book is available because of increasing use of nonmetallic materials in aircraft structural components and use of electronic equipment for control of critical flight operations and navigation.

Fisher, F. A.; Plumer, J. A.

1980-01-01

114

Hypersonic reconnaissance aircraft  

NASA Technical Reports Server (NTRS)

A conceptual design of a hypersonic reconnaissance aircraft for the U.S. Navy is discussed. After eighteen weeks of work, a waverider design powered by two augmented turbofans was chosen. The aircraft was designed to be based on an aircraft carrier and to cruise 6,000 nautical miles at Mach 4;80,000 feet and above. As a result the size of the aircraft was only allowed to have a length of eighty feet, fifty-two feet in wingspan, and roughly 2,300 square feet in planform area. Since this is a mainly cruise aircraft, sixty percent of its 100,000 pound take-off weight is JP fuel. At cruise, the highest temperature that it will encounter is roughly 1,100 F, which can be handled through the use of a passive cooling system.

Bulk, Tim; Chiarini, David; Hill, Kevin; Kunszt, Bob; Odgen, Chris; Truong, Bon

1992-01-01

115

Why aircraft disinsection?  

PubMed Central

A serious problem is posed by the inadvertent transport of live mosquitoes aboard aircraft arriving from tropical countries where vector-borne diseases are endemic. Surveys at international airports have found many instances of live insects, particularly mosquitoes, aboard aircraft arriving from countries where malaria and arboviruses are endemic. In some instances mosquito species have been established in countries in which they have not previously been reported. A serious consequence of the transport of infected mosquitoes aboard aircraft has been the numerous cases of "airport malaria" reported from Europe, North America and elsewhere. There is an important on-going need for the disinsection of aircraft coming from airports in tropical disease endemic areas into nonendemic areas. The methods and materials available for use in aircraft disinsection and the WHO recommendations for their use are described. PMID:10994283

Gratz, N. G.; Steffen, R.; Cocksedge, W.

2000-01-01

116

Aircraft operations management manual  

NASA Technical Reports Server (NTRS)

The NASA aircraft operations program is a multifaceted, highly diverse entity that directly supports the agency mission in aeronautical research and development, space science and applications, space flight, astronaut readiness training, and related activities through research and development, program support, and mission management aircraft operations flights. Users of the program are interagency, inter-government, international, and the business community. This manual provides guidelines to establish policy for the management of NASA aircraft resources, aircraft operations, and related matters. This policy is an integral part of and must be followed when establishing field installation policy and procedures covering the management of NASA aircraft operations. Each operating location will develop appropriate local procedures that conform with the requirements of this handbook. This manual should be used in conjunction with other governing instructions, handbooks, and manuals.

1992-01-01

117

Predicting Visibility of Aircraft  

PubMed Central

Visual detection of aircraft by human observers is an important element of aviation safety. To assess and ensure safety, it would be useful to be able to be able to predict the visibility, to a human observer, of an aircraft of specified size, shape, distance, and coloration. Examples include assuring safe separation among aircraft and between aircraft and unmanned vehicles, design of airport control towers, and efforts to enhance or suppress the visibility of military and rescue vehicles. We have recently developed a simple metric of pattern visibility, the Spatial Standard Observer (SSO). In this report we examine whether the SSO can predict visibility of simulated aircraft images. We constructed a set of aircraft images from three-dimensional computer graphic models, and measured the luminance contrast threshold for each image from three human observers. The data were well predicted by the SSO. Finally, we show how to use the SSO to predict visibility range for aircraft of arbitrary size, shape, distance, and coloration. PMID:19462007

Watson, Andrew; Ramirez, Cesar V.; Salud, Ellen

2009-01-01

118

Predicting visibility of aircraft.  

PubMed

Visual detection of aircraft by human observers is an important element of aviation safety. To assess and ensure safety, it would be useful to be able to be able to predict the visibility, to a human observer, of an aircraft of specified size, shape, distance, and coloration. Examples include assuring safe separation among aircraft and between aircraft and unmanned vehicles, design of airport control towers, and efforts to enhance or suppress the visibility of military and rescue vehicles. We have recently developed a simple metric of pattern visibility, the Spatial Standard Observer (SSO). In this report we examine whether the SSO can predict visibility of simulated aircraft images. We constructed a set of aircraft images from three-dimensional computer graphic models, and measured the luminance contrast threshold for each image from three human observers. The data were well predicted by the SSO. Finally, we show how to use the SSO to predict visibility range for aircraft of arbitrary size, shape, distance, and coloration. PMID:19462007

Watson, Andrew; Ramirez, Cesar V; Salud, Ellen

2009-01-01

119

Tropospheric sampling with aircraft  

SciTech Connect

Aircraft constitute a unique environment which places stringent requirements on the instruments used to measure the concentrations of atmospheric trace gases and aerosols. Some of these requirements such as minimization of size, weight, and power consumption are general; others are specific to individual techniques. This review presents the basic principles and considerations governing the deployment of trace gas and aerosol instrumentation on an aircraft. An overview of common instruments illustrates these points and provides guidelines for designing and using instruments on aircraft-based measurement programs.

Daum, P.H.; Springston, S.R.

1991-03-01

120

OVRhyp, Scramjet Test Aircraft  

NASA Technical Reports Server (NTRS)

A preliminary design for an unmanned hypersonic research vehicle to test scramjet engines is presented. The aircraft will be launched from a carrier aircraft at an altitude of 40,000 feet at Mach 0.8. The vehicle will then accelerate to Mach 6 at an altitude of 100,000 feet. At this stage the prototype scramjet will be employed to accelerate the vehicle to Mach 10 and maintain Mach 10 flight for 2 minutes. The aircraft will then decelerate and safely land.

Aslan, J.; Bisard, T.; Dallinga, S.; Draper, K.; Hufford, G.; Peters, W.; Rogers, J.

1990-01-01

121

Loftin Collection - Boeing Aircraft  

NASA Technical Reports Server (NTRS)

Either a F2B-1 or F3B-1, both aircraft were built by Boeing and both were powered by Pratt and Whitney Wasp engines. These fighters were intended for Navy shipboard use. Boeing F3B-1: While most Boeing F3B-1s served the U. S. Navy aircraft carriers the Lexington and the Saratoga, this example flew in NACA hands at the Langley Memorial Aeronautical Laboratory in the late 1920's. Also known as the Boeing Model 77, the aircraft was the next to last F3B-1 build in November 1928.

1933-01-01

122

Solar thermal aircraft  

DOEpatents

A solar thermal powered aircraft powered by heat energy from the sun. A heat engine, such as a Stirling engine, is carried by the aircraft body for producing power for a propulsion mechanism, such as a propeller. The heat engine has a thermal battery in thermal contact with it so that heat is supplied from the thermal battery. A solar concentrator, such as reflective parabolic trough, is movably connected to an optically transparent section of the aircraft body for receiving and concentrating solar energy from within the aircraft. Concentrated solar energy is collected by a heat collection and transport conduit, and heat transported to the thermal battery. A solar tracker includes a heliostat for determining optimal alignment with the sun, and a drive motor actuating the solar concentrator into optimal alignment with the sun based on a determination by the heliostat.

Bennett, Charles L. (Livermore, CA)

2007-09-18

123

Aircraft Safety Improvement  

NASA Technical Reports Server (NTRS)

Fabrication and testing of honeycomb sandwich aircraft panels are discussed. Also described is the use of the following instruments: thermogravimetric analyzer, differential scanning calorimeter, limiting oxygen index, and infrared spectrometer.

Kao, G.

1985-01-01

124

Aircraft parameter estimation  

NASA Technical Reports Server (NTRS)

The aircraft parameter estimation problem is used to illustrate the utility of parameter estimation, which applies to many engineering and scientific fields. Maximum likelihood estimation has been used to extract stability and control derivatives from flight data for many years. This paper presents some of the basic concepts of aircraft parameter estimation and briefly surveys the literature in the field. The maximum likelihood estimator is discussed, and the basic concepts of minimization and estimation are examined for a simple simulated aircraft example. The cost functions that are to be minimized during estimation are defined and discussed. Graphic representations of the cost functions are given to illustrate the minimization process. Finally, the basic concepts are generalized, and estimation from flight data is discussed. Some of the major conclusions for the simulated example are also developed for the analysis of flight data from the F-14, highly maneuverable aircraft technology (HiMAT), and space shuttle vehicles.

Iliff, Kenneth W.

1987-01-01

125

Aircraft Engine Emissions. [conference  

NASA Technical Reports Server (NTRS)

A conference on a aircraft engine emissions was held to present the results of recent and current work. Such diverse areas as components, controls, energy efficient engine designs, and noise and pollution reduction are discussed.

1977-01-01

126

Aircraft electromagnetic compatibility  

NASA Technical Reports Server (NTRS)

Illustrated are aircraft architecture, electromagnetic interference environments, electromagnetic compatibility protection techniques, program specifications, tasks, and verification and validation procedures. The environment of 400 Hz power, electrical transients, and radio frequency fields are portrayed and related to thresholds of avionics electronics. Five layers of protection for avionics are defined. Recognition is given to some present day electromagnetic compatibility weaknesses and issues which serve to reemphasize the importance of EMC verification of equipment and parts, and their ultimate EMC validation on the aircraft. Proven standards of grounding, bonding, shielding, wiring, and packaging are laid out to help provide a foundation for a comprehensive approach to successful future aircraft design and an understanding of cost effective EMC in an aircraft setting.

Clarke, Clifton A.; Larsen, William E.

1987-01-01

127

Laminar Flow Aircraft Certification  

NASA Technical Reports Server (NTRS)

Various topics telative to laminar flow aircraft certification are discussed. Boundary layer stability, flaps for laminar flow airfoils, computational wing design studies, manufacturing requirements, windtunnel tests, and flow visualization are among the topics covered.

Williams, Louis J. (compiler)

1986-01-01

128

Advanced hypersonic aircraft design  

NASA Technical Reports Server (NTRS)

The objective of this design project is to develop the hypersonic reconnaissance aircraft to replace the SR-71 and to complement existing intelligence gathering devices. The initial design considerations were to create a manned vehicle which could complete its mission with at least two airborne refuelings. The aircraft must travel between Mach 4 and Mach 7 at an altitude of 80,000 feet for a maximum range of 12,000 nautical miles. The vehicle should have an air breathing propulsion system at cruise. With a crew of two, the aircraft should be able to take off and land on a 10,000 foot runway, and the yearly operational costs were not to exceed $300 million. Finally, the aircraft should exhibit stealth characteristics, including a minimized radar cross-section (RCS) and a reduced sonic boom. The technology used in this vehicle should allow for production between the years 1993 and 1995.

Utzinger, Rob; Blank, Hans-Joachim; Cox, Craig; Harvey, Greg; Mckee, Mike; Molnar, Dave; Nagy, Greg; Petersen, Steve

1992-01-01

129

Aircraft Materials Test Bank  

NSDL National Science Digital Library

This Microsoft Word document from the Aerospace Manufacturing Education Project provides a bank of test questions on materials used in the aircraft industry. 35 test questions and their correct answers are included in this test bank.

2012-11-13

130

Aircraft as Research Tools  

NASA Technical Reports Server (NTRS)

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

1999-01-01

131

150 Passenger Commercial Aircraft  

NASA Technical Reports Server (NTRS)

It has been projected that the need for a short-range mid-sized, aircraft is increasing. The future strategy to decrease long-haul flights will increase the demand for short-haul flights. Since passengers prefer to meet their destinations quickly, airlines will increase the frequency of flights, which will reduce the passenger load on the aircraft. If a point-to-point flight is not possible, passengers will prefer only a one-stop short connecting flight to their final destination. A 150-passenger aircraft is an ideal vehicle for these situations. It is mid-sized aircraft and has a range of 3000 nautical miles. This type of aircraft would market U.S. domestic flights or inter-European flight routes. The objective of the design of the 150-passenger aircraft is to minimize fuel consumption. The configuration of the aircraft must be optimized. This aircraft must meet CO2 and NOx emissions standards with minimal acquisition price and operating costs. This report contains all the work that has been performed for the completion of the design of a 150 passenger commercial aircraft. The methodology used is the Technology Identification, Evaluation, and Selection (TIES) developed at Georgia Tech Aerospace Systems Design laboratory (ASDL). This is an eight-step conceptual design process to evaluate the probability of meeting the design constraints. This methodology also allows for the evaluation of new technologies to be implemented into the design. The TIES process begins with defining the problem with a need established and a market targeted. With the customer requirements set and the target values established, a baseline concept is created. Next, the design space is explored to determine the feasibility and viability of the baseline aircraft configuration. If the design is neither feasible nor viable, new technologies can be implemented to open up the feasible design space and allow for a plausible solution. After the new technologies are identified, they must be evaluated to determine the physical compatibility of integrating multiple technologies and then the impact on the design, both improvements and degradations, must be determined. These technologies are assessed deterministically. Again, Response Surface Equations (RSEs) are developed to allow for a full factorial evaluation of the combinations of the technologies. The best combination of technologies is selected and then the design space is again reevaluated for feasibility and viability.

Bucovsky, Adrian; Romli, Fairuz I.; Rupp, Jessica

2002-01-01

132

Damage tolerance for commuter aircraft  

NASA Technical Reports Server (NTRS)

The damage tolerance experience in the United States Air Force with military aircraft and in the commercial world with large transport category aircraft indicates that a similar success could be achieved in commuter aircraft. The damage tolerance process is described for the purpose of defining the approach that could be used for these aircraft to ensure structural integrity. Results of some of the damage tolerance assessments for this class of aircraft are examined to illustrate the benefits derived from this approach. Recommendations are given for future damage tolerance assessment of existing commuter aircraft and on the incorporation of damage tolerance capability in new designs.

Lincoln, John W.

1992-01-01

133

Pathfinder Aircraft in Flight  

NASA Technical Reports Server (NTRS)

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

1995-01-01

134

Aircraft icing instrumentation: Unfilled needs. [rotary wing aircraft  

NASA Technical Reports Server (NTRS)

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

Kitchens, P. F.

1980-01-01

135

Aircraft Design Analysis  

NASA Technical Reports Server (NTRS)

The helicopter pictured is the twin-turbine S-76, produced by Sikorsky Aircraft division of United Technologies, Stratford, Connecticut. It is the first transport helicopter ever dey n e d purely as a commercial vehicle rather than an adaptation of a military design. Being built in large numbers for customers in 16 countries, the S-76 is intended for offshore oil rig support, executive transportation and general utility service. The craft carries 12 passengers plus a crew of two and has a range of more than 450 miles-yet it weighs less than 10,000 pounds. Significant weight reduction was achieved by use of composite materials, which are generally lighter but stronger than conventional aircraft materials. NASA composite technology played a part in development of the S-76. Under contract with NASA's Langley Research Center, Sikorsky Aircraft designed and flight-tested a helicopter airframe of advanced composite materials.

1979-01-01

136

Transport aircraft accident dynamics  

NASA Technical Reports Server (NTRS)

A study was carried out of 112 impact survivable jet transport aircraft accidents (world wide) of 27,700 kg (60,000 lb.) aircraft and up extending over the last 20 years. This study centered on the effect of impact and the follow-on events on aircraft structures and was confined to the approach, landing and takeoff segments of the flight. The significant characteristics, frequency of occurrence and the effect on the occupants of the above data base were studied and categorized with a view to establishing typical impact scenarios for use as a basis of verifying the effectiveness of potential safety concepts. Studies were also carried out of related subjects such as: (1) assessment of advanced materials; (2) human tolerance to impact; (3) merit functions for safety concepts; and (4) impact analysis and test methods.

Cominsky, A.

1982-01-01

137

Alternative aircraft fuels technology  

NASA Technical Reports Server (NTRS)

NASA is studying the characteristics of future aircraft fuels produced from either petroleum or nonpetroleum sources such as oil shale or coal. These future hydrocarbon based fuels may have chemical and physical properties that are different from present aviation turbine fuels. This research is aimed at determining what those characteristics may be, how present aircraft and engine components and materials would be affected by fuel specification changes, and what changes in both aircraft and engine design would be required to utilize these future fuels without sacrificing performance, reliability, or safety. This fuels technology program was organized to include both in-house and contract research on the synthesis and characterization of fuels, component evaluations of combustors, turbines, and fuel systems, and, eventually, full-scale engine demonstrations. A review of the various elements of the program and significant results obtained so far are presented.

Grobman, J.

1976-01-01

138

14 CFR 21.182 - Aircraft identification.  

Code of Federal Regulations, 2014 CFR

...1) A special flight permit. (2) An experimental certificate for an aircraft not issued for the purpose of operating amateur-built aircraft, operating primary kit-built aircraft, or operating light-sport aircraft. (3) A change from...

2014-01-01

139

Aircraft engine pollution reduction  

NASA Technical Reports Server (NTRS)

The effect of engine operation on the types and levels of the major aircraft engine pollutants is described and the major factors governing the formation of these pollutants during the burning of hydrocarbon fuel are discussed. Methods which are being explored to reduce these pollutants are discussed and their application to several experimental research programs are pointed out. Results showing significant reductions in the levels of carbon monoxide, unburned hydrocarbons, and oxides of nitrogen obtained from experimental combustion research programs are presented and discussed to point out potential application to aircraft engines.

Rudey, R. A.

1972-01-01

140

Dryden Aircraft Photo Collection  

NSDL National Science Digital Library

Any lover of airplanes is bound to enjoy this collection of digitized photos "of many of the unique research aircraft" from the NASA Dryden Flight Research Center in Edwards, California. The photos go back to the 1940s and into the present. Multiple resolutions are available. The collection is regularly updated. Visitors can browse the entire list alphabetically, or go right to the most recent postings in "What's New" or check out the Slide Show of selected photos. Each photo is accompanied by a short description of the aircraft's flight history. Some other miscellaneous photos include the shock wave of a T-38 at Mach 1.1 and photos of Dryden pilots.

141

Aircraft Laminar Flow Control  

NASA Technical Reports Server (NTRS)

Aircraft laminar flow control (LFC) from the 1930's through the 1990's is reviewed and the current status of the technology is assessed. Examples are provided to demonstrate the benefits of LFC for subsonic and supersonic aircraft. Early studies related to the laminar boundary-layer flow physics, manufacturing tolerances for laminar flow, and insect-contamination avoidance are discussed. LFC concept studies in wind-tunnel and flight experiments are the major focus of the paper. LFC design tools are briefly outlined for completeness.

Joslin, Ronald D.

1998-01-01

142

Alternative aircraft fuels  

NASA Technical Reports Server (NTRS)

The efficient utilization of fossil fuels by future jet aircraft may necessitate the broadening of current aviation turbine fuel specifications. The most significant changes in specifications would be an increased aromatics content and a higher final boiling point in order to minimize refinery energy consumption and costs. These changes would increase the freezing point and might lower the thermal stability of the fuel, and could cause increased pollutant emissions, increased combustor liner temperatures, and poorer ignition characteristics. The effects that broadened specification fuels may have on present-day jet aircraft and engine components and the technology required to use fuels with broadened specifications are discussed.

Longwell, J. P.; Grobman, J. S.

1977-01-01

143

Aircraft Flutter Testing  

NASA Technical Reports Server (NTRS)

Wilmer Reed gained international recognition for his innovative research, contributions and patented ideas relating to flutter and aeroelasticity of aerospace vehicles at Langley Research Center. In the early 1980's, Reed retired from Langley and joined the engineering staff of Dynamic Engineering Inc. While at DEI, Reed conceived and patented the DEI Flutter Exciter, now used world-wide in flight flutter testing of new or modified aircraft designs. When activated, the DEI Flutter Exciter alternately deflects the airstream upward and downward in a rapid manner, creating a force similar to that produced by an oscillating trailing edge flap. The DEI Flutter Exciter is readily adaptable to a variety of aircraft.

1997-01-01

144

Safety hazard of aircraft icing  

NASA Technical Reports Server (NTRS)

The problem of aircraft icing is reported as well as the type of aircraft affected, the pilots involved, and an identification of the areas where reduction in icing accidents are readily accomplished.

Mclean, J. C., Jr.

1979-01-01

145

Optical communications for transport aircraft  

NASA Technical Reports Server (NTRS)

Optical communications for transport aircraft are discussed. The problem involves: increasing demand for radio-frequency bands from an enlarging pool of users (aircraft, ground and sea vehicles, fleet operators, traffic control centers, and commercial radio and television); desirability of providing high-bandwidth dedicated communications to and from every aircraft in the National Airspace System; need to support communications, navigation, and surveillance for a growing number of aircraft; and improved meteorological observations by use of probe aircraft. The solution involves: optical signal transmission support very high data rates; optical transmission of signals between aircraft, orbiting satellites, and ground stations, where unobstructed line-of-sight is available; conventional radio transmissions of signals between aircraft and ground stations, where optical line-of-sight is unavailable; and radio priority given to aircraft in weather.

Stengel, Robert

1994-01-01

146

Optical communications for transport aircraft  

NASA Astrophysics Data System (ADS)

Optical communications for transport aircraft are discussed. The problem involves: increasing demand for radio-frequency bands from an enlarging pool of users (aircraft, ground and sea vehicles, fleet operators, traffic control centers, and commercial radio and television); desirability of providing high-bandwidth dedicated communications to and from every aircraft in the National Airspace System; need to support communications, navigation, and surveillance for a growing number of aircraft; and improved meteorological observations by use of probe aircraft. The solution involves: optical signal transmission support very high data rates; optical transmission of signals between aircraft, orbiting satellites, and ground stations, where unobstructed line-of-sight is available; conventional radio transmissions of signals between aircraft and ground stations, where optical line-of-sight is unavailable; and radio priority given to aircraft in weather.

Stengel, Robert

1994-02-01

147

System description and analysis. Part 1: Feasibility study for helicopter/VTOL wide-angle simulation image generation display system  

NASA Technical Reports Server (NTRS)

A preliminary design for a helicopter/VSTOL wide angle simulator image generation display system is studied. The visual system is to become part of a simulator capability to support Army aviation systems research and development within the near term. As required for the Army to simulate a wide range of aircraft characteristics, versatility and ease of changing cockpit configurations were primary considerations of the study. Due to the Army's interest in low altitude flight and descents into and landing in constrained areas, particular emphasis is given to wide field of view, resolution, brightness, contrast, and color. The visual display study includes a preliminary design, demonstrated feasibility of advanced concepts, and a plan for subsequent detail design and development. Analysis and tradeoff considerations for various visual system elements are outlined and discussed.

1977-01-01

148

Light aircraft sound transmission study  

NASA Technical Reports Server (NTRS)

The revived interest in the design of propeller driven aircraft is based on increasing fuel prices as well as on the need for bigger short haul and commuter aircraft. A major problem encountered with propeller driven aircraft is propeller and exhaust noise that is transmitted through the fuselage sidewall structure. Part of the work which was conducted during the period April 1 to August 31, 1983, on the studies of sound transmission through light aircraft walls is presented.

Atwal, M.; David, J.; Heitman, K.; Crocker, M. J.

1983-01-01

149

Stearman Hammond Y-1 aircraft  

NASA Technical Reports Server (NTRS)

The Stearman Hammond Y aircraft was produced to compete in a 'Safe Aircraft' competition in January 1939. It was the winner of the $700 prize which was sponsored by the Department of Commerce. The model Y used many of the safety features the NACA's Fred Weick developed for his W-1 aircraft.

1939-01-01

150

Aircraft as a meteorological sensor  

E-print Network

Aircraft as a meteorological sensor Using Mode-S Enhanced Surveillance data to derive upper air Meteorological Institute 2 | The aircraft as a meteorological sensor Photo cover: A KLM Airbus A330-200 lands at Amsterdam Airport Schiphol in The Netherlands. Increased aircraft movements will result in a greater number

Haak, Hein

151

Aircraft Wake RCS Measurement  

NASA Technical Reports Server (NTRS)

A series of multi-frequency radar measurements of aircraft wakes at altitudes of 5,000 to 25,00 ft. were performed at Kwajalein, R.M.I., in May and June of 1990. Two aircraft were tested, a Learjet 35 and a Lockheed C-5A. The cross-section of the wake of the Learjet was too small for detection at Kwajalein. The wake of the C-5A, although also very small, was detected and measured at VHF, UHF, L-, S-, and C-bands, at distances behind the aircraft ranging from about one hundred meters to tens of kilometers. The data suggest that the mechanism by which aircraft wakes have detectable radar signatures is, contrary to previous expectations, unrelated to engine exhaust but instead due to turbulent mixing by the wake vortices of pre-existing index of refraction gradients in the ambient atmosphere. These measurements were of necessity performed with extremely powerful and sensitive instrumentation radars, and the wake cross-section is too small for most practical applications.

Gilson, William H.

1994-01-01

152

Raven Aircraft Launch  

USGS Multimedia Gallery

USGS contractor Phil Owen of EnrGies, Inc. launches a Raven aircraft on the Missouri River near Lower Brule, S.D., during an August 2012 mission to monitor erosion on the river. Owen is accompanied by USGS and Bureau of Indian Affairs researchers.  ...

153

IMA aircraft improvements  

Microsoft Academic Search

Integrated modular avionics (IMA) is being suggested as the means by which new capabilities can be deployed on aircraft at an affordable cost. RTCA SC-200 is presently considering the guidance document for IMA. All of the functionality that IMA offers can be achieved through a conventional federated architecture; however, the cost, size, and weight penalties of the federated solution make

Chris Wilkinson

2005-01-01

154

Commercial aircraft wake vortices  

NASA Astrophysics Data System (ADS)

This paper discusses the problem of wake vortices shed by commercial aircraft. It presents a consolidated European view on the current status of knowledge of the nature and characteristics of aircraft wakes and of technical and operational procedures of minimizing and predicting the vortex strength and avoiding wake encounters. Methodological aspects of data evaluation and interpretation, like the description of wake ages, the characterization of wake vortices, and the proper evaluation of wake data from measurement and simulation, are addressed in the first part. In the second part an inventory of our knowledge is given on vortex characterization and control, prediction and monitoring of vortex decay, vortex detection and warning, vortex encounter models, and wake-vortex safety assessment. Each section is concluded by a list of questions and required actions which may help to guide further research activities. The primary objective of the joint international efforts in wake-vortex research is to avoid potentially hazardous wake encounters for aircraft. Shortened aircraft separations under appropriate meteorological conditions, whilst keeping or even increasing the safety level, is the ultimate goal. Reduced time delays on the tactical side and increased airport capacities on the strategic side will be the benefits of these ambitious ventures for the air transportation industry and services.

Gerz, Thomas; Holzäpfel, Frank; Darracq, Denis

2002-04-01

155

Aircraft Inlet Ducts  

NASA Technical Reports Server (NTRS)

After studying three Tech Briefs reports on NASA submerged duct technology developed for high performance aircraft, Wilhelm Cashen was able to adapt the technology to the induction intercooler system of turbocharged lightplanes. In lightplane installations, the submerged ducts introduce cool "ram" air to the propulsion system for greater operating efficiency.

1984-01-01

156

Aircraft thrust control  

NASA Technical Reports Server (NTRS)

An integrated control system for coaxial counterrotating aircraft propulsors driven by a common gas turbine engine. The system establishes an engine pressure ratio by control of fuel flow and uses the established pressure ratio to set propulsor speed. Propulsor speed is set by adjustment of blade pitch.

Walker, Neil (Inventor); Day, Stanley G. (Inventor); Collopy, Paul D. (Inventor); Bennett, George W. (Inventor)

1988-01-01

157

Aircraft adaptive learning control  

NASA Technical Reports Server (NTRS)

The optimal control theory of stochastic linear systems is discussed in terms of the advantages of distributed-control systems, and the control of randomly-sampled systems. An optimal solution to longitudinal control is derived and applied to the F-8 DFBW aircraft. A randomly-sampled linear process model with additive process and noise is developed.

Lee, P. S. T.; Vanlandingham, H. F.

1979-01-01

158

Robots for Aircraft Maintenance  

NASA Technical Reports Server (NTRS)

Marshall Space Flight Center charged USBI (now Pratt & Whitney) with the task of developing an advanced stripping system based on hydroblasting to strip paint and thermal protection material from Space Shuttle solid rocket boosters. A robot, mounted on a transportable platform, controls the waterjet angle, water pressure and flow rate. This technology, now known as ARMS, has found commercial applications in the removal of coatings from jet engine components. The system is significantly faster than manual procedures and uses only minimal labor. Because the amount of "substrate" lost is minimal, the life of the component is extended. The need for toxic chemicals is reduced, as is waste disposal and human protection equipment. Users of the ARMS work cell include Delta Air Lines and the Air Force, which later contracted with USBI for development of a Large Aircraft Paint Stripping system (LARPS). LARPS' advantages are similar to ARMS, and it has enormous potential in military and civil aircraft maintenance. The technology may also be adapted to aircraft painting, aircraft inspection techniques and paint stripping of large objects like ships and railcars.

1993-01-01

159

Raven Unmanned Aircraft.  

USGS Multimedia Gallery

Lance Brady of the US Bureau of Land Management observes a USGS Raven unmanned aircraft in action June 20, 2012 at Lake Aldwell on the Elwha River south of Olympic National Park, Wash. USGS and BLM are cooperating on science missions to study hydrology, sedimentation, revegetation and other issues r...

160

Testing Aircraft Generators  

Microsoft Academic Search

The modern fighting airplane requires a large amount of electric power for its successful operation. The aircraft generator provides a reliable source of power at the lowest possible weight. The development of these generators has required close co-ordination of design, testing, and interpretation of test results. The tests include raw material, parts, laboratory, life, mechanical, and flight tests. This paper

H. E. Keneipp

1944-01-01

161

Aircraft radar echoes characterization  

Microsoft Academic Search

Electromagnetic wave diffraction and reflection theories enable prediction of most of the effects generated by radar echoes on aircraft. However, it is difficult to modelize some complex effects originating in canopies, radomes and cavities. In order to supplement the present theoretical knowledge by experimental results obtained on actual targets, ONERA has developed a novel analysis method allowing the generation of

C. Pouit

1980-01-01

162

Aircraft to Medicine  

NASA Technical Reports Server (NTRS)

This video discusses how the technology of computer modeling can improve the design and durability of artificial joints for human joint replacement surgery. Also, ultrasound, originally used to detect structural flaws in aircraft, can also be used to quickly assess the severity of a burn patient's injuries, thus aiding the healing process.

1991-01-01

163

Nocturnal aircraft noise effects.  

PubMed

Noise protection associated with the construction and extension of airports in the Federal Republic of Germany has been regulated by the law for protection against aircraft noise since 1971. This legislation is due for revision because of different aspects. One aspect is the growth of air traffic which has led many airports to the limits of their capacity and in search of new ways of adaptation to the increasing demand for flight services. Another aspect is the increasing concern of the population about noise effects which has to be addressed by better protection against the effects of aircraft noise. The framework conditions of policy in terms of society as a whole, its health and economic environment need to be put into effect by political action. Science can contribute to this goal by performing noise effects research and by providing recommendations to the political body. However, it remains controversial, what measures are necessary or adequate to assure effective protection of the population against aircraft noise. This is particularly true for the protection of rest and sleep at night. The problem of finding a common basis for adequate recommendations is associated with (1) the low number of primary studies, which also exhibited highly variable results and assessments, (2) the handling of acoustic or psycho-acoustic dimensions for quantifying psychological or physiological reactions, and (3) the conception of how far preventive measures have to go to prove effective. With this in mind, the DLR Institute for Aerospace Medicine is conducting a large-scale, multi-stage study for investigating the acute effects of nocturnal aircraft noise on human sleep. This enterprise is implemented in the framework of the HGF/DLR project "Quiet Air Traffic" for developing sustainable assessment criteria for human-specific effects of aircraft noise at night. PMID:15070533

Basner, M; Samel, A

2004-01-01

164

Turboprop cargo aircraft systems study  

NASA Technical Reports Server (NTRS)

The effects of using advanced turboprop propulsion systems to reduce the fuel consumption and direct operating costs of cargo aircraft were studied, and the impact of these systems on aircraft noise and noise prints around a terminal area was determined. Parametric variations of aircraft and propeller characteristics were investigated to determine their effects on noiseprint areas, fuel consumption, and direct operating costs. From these results, three aircraft designs were selected and subjected to design refinements and sensitivity analyses. Three competitive turbofan aircraft were also defined from parametric studies to provide a basis for comparing the two types of propulsion.

Muehlbauer, J. C.; Hewell, J. G., Jr.; Lindenbaum, S. P.; Randall, C. C.; Searle, N.; Stone, R. G., Jr.

1981-01-01

165

Hovering and Transition Flight Tests of a 1/5-Scale Model of a Jet-Powered Vertical-Attitude VTOL Research Airplane  

NASA Technical Reports Server (NTRS)

An experimental investigation has been made to determine the dynamic stability and control characteristics of a 1/5-scale flying model of a jet-powered vertical-attitude VTOL research airplane in hovering and transition flight. The model was powered with either a hydrogen peroxide rocket motor or a compressed-air jet exhausting through an ejector tube to simulate the turbojet engine of the airplane. The gyroscopic effects of the engine were simulated by a flywheel driven by compressed-air jets. In hovering flight the model was controlled by jet-reaction controls which consisted of a swiveling nozzle on the main jet and a movable nozzle on each wing tip; and in forward flight the model was controlled by elevons and a rudder. If the gyroscopic effects of the jet engine were not represented, the model could be flown satisfactorily in hovering flight without any automatic stabilization devices. When the gyroscopic effects of the jet engine were represented, however, the model could not be controlled without the aid of artificial stabilizing devices because of the gyroscopic coupling of the yawing and pitching motions. The use of pitch and yaw dampers made these motions completely stable and the model could then be controlled very easily. In the transition flight tests, which were performed only with the automatic pitch and yaw dampers operating, it was found that the transition was very easy to perform either with or without the engine gyroscopic effects simulated, although the model had a tendency to fly in a rolled and sideslipped attitude at angles of attack between approximately 25 deg and 45 deg because of static directional instability in this range.

Smith, Charles C., Jr.

1961-01-01

166

Hovering and Transition Flight Tests of a 1/5-Scale Model of a Jet-Powered Vertical-Attitude VTOL Research Airplane  

NASA Technical Reports Server (NTRS)

An experimental investigation has been made to determine the dynamic stability and control characteristics of a 1/5-scale flying model of a jet-powered vertical-attitude VTOL research airplane in hovering and transition flight. The model was powered with either a hydrogen peroxide rocket motor or a compressed-air jet exhausting through an ejector tube to simulate the turbojet engine of the airplane. The gyroscopic effects of the engine were simulated by a flywheel driven by compressed-air jets. In hovering flight the model was controlled by jet-reaction controls which consisted of a swiveling nozzle on the main jet and a movable nozzle on each wing tip; and in forward flight the model was controlled by elevons and a rudder. If the gyroscopic effects of the jet engine were not represented, the model could be flown satisfactorily in hovering flight without any automatic stabilization devices. When the gyroscopic effects of the jet engine were represented, however, the model could not be controlled without the aid of artificial stabilizing devices because of the gyroscopic coupling of the yawing and pitching motions. The use of pitch and yaw dampers made these motions completely stable and the model could then be controlled very easily. In the transition flight tests, which were performed only with the automatic pitch and yaw dampers operating, it was found that the transition was very easy to perform either with or without the engine gyroscopic effects simulated, although the model had a tendency to fly in a rolled and sideslipped attitude at angles of attack between approximately 25 and 45 deg because of static directional instability in this range.

Smith, Charles C., Jr.

1958-01-01

167

Aircraft turbofan noise  

NASA Technical Reports Server (NTRS)

Turbofan noise generation and suppression in aircraft engines are reviewed. The chain of physical processes which connect unsteady flow interactions with fan blades to far field noise is addressed. Mechanism identification and description, duct propagation, radiation and acoustic suppression are discussed. The experimental technique of fan inflow static tests are discussed. Rotor blade surface pressure and wake velocity measurements aid in the determination of the types and strengths of the generation mechanisms. Approaches to predicting or measuring acoustic mode content, optimizing treatment impedance to maximize attenuation, translating impedance into porous wall structure and interpreting far field directivity patterns are illustrated by comparisons of analytical and experimental results. The interdependence of source and acoustic treatment design to minimize far field noise is emphasized. Area requiring further research are discussed and the relevance of aircraft turbofan results to quieting other turbomachinery installations is addressed.

Groeneweg, J. F.; Rice, E. J.

1983-01-01

168

Air pollution from aircraft  

NASA Technical Reports Server (NTRS)

Forty-one annotated abstracts of reports generated at MIT and the University of Sheffield are presented along with summaries of the technical projects undertaken. Work completed includes: (1) an analysis of the soot formation and oxidation rates in gas turbine combustors, (2) modelling the nitric oxide formation process in gas turbine combustors, (3) a study of the mechanisms causing high carbon monoxide emissions from gas turbines at low power, (4) an analysis of the dispersion of pollutants from aircraft both around large airports and from the wakes of subsonic and supersonic aircraft, (5) a study of the combustion and flow characteristics of the swirl can modular combustor and the development and verification of NO sub x and CO emissions models, (6) an analysis of the influence of fuel atomizer characteristics on the fuel-air mixing process in liquid fuel spray flames, and (7) the development of models which predict the stability limits of fully and partially premixed fuel-air mixtures.

Heywood, J. B.; Fay, J. A.; Chigier, N. A.

1979-01-01

169

Project report: Aircraft  

SciTech Connect

Analyses of scenarios of past and possible future emissions are an important aspect of assessing the potential environmental effects from aircraft, including the proposed high speed civil transport (HSCT). The development of a detailed three-dimensional database that accurately represents the integration of all aircraft emissions along realistic flight paths for such scenarios requires complex computational modeling capabilities. Such a detailed data set is required for the scenarios evaluated in this interim assessment. Within the NASA High-Speed Research Program, the Emissions Scenarios Committee provides a forum for identifying the required scenarios and evaluating the resulting database being developed with the advanced emissions modeling capabilities at the Boeing Company and McDonnell Douglas Corporation.

Wuebbles, D.J. [Lawrence Livermore National Lab., CA (United States); Baughcum, S. [Boeing Co., Seattle, WA (United States). Commercial Airplane Group; Metwally, M. [McDonnell Douglas Corp., Long Beach, CA (United States); Seals, R. [National Aeronautics and Space Administration, Hampton, VA (United States). Atmospheric Science Div.

1994-04-01

170

Autonomous aircraft initiative study  

NASA Technical Reports Server (NTRS)

The results of a consulting effort to aid NASA Ames-Dryden in defining a new initiative in aircraft automation are described. The initiative described is a multi-year, multi-center technology development and flight demonstration program. The initiative features the further development of technologies in aircraft automation already being pursued at multiple NASA centers and Department of Defense (DoD) research and Development (R and D) facilities. The proposed initiative involves the development of technologies in intelligent systems, guidance, control, software development, airborne computing, navigation, communications, sensors, unmanned vehicles, and air traffic control. It involves the integration and implementation of these technologies to the extent necessary to conduct selected and incremental flight demonstrations.

Hewett, Marle D.

1991-01-01

171

Aircraft Design Software  

NASA Technical Reports Server (NTRS)

Successful commercialization of the AirCraft SYNThesis (ACSYNT) tool has resulted in the creation of Phoenix Integration, Inc. ACSYNT has been exclusively licensed to the company, an outcome of a seven year, $3 million effort to provide unique software technology to a focused design engineering market. Ames Research Center formulated ACSYNT and in working with the Virginia Polytechnic Institute CAD Laboratory, began to design and code a computer-aided design for ACSYNT. Using a Joint Sponsored Research Agreement, Ames formed an industry-government-university alliance to improve and foster research and development for the software. As a result of the ACSYNT Institute, the software is becoming a predominant tool for aircraft conceptual design. ACSYNT has been successfully applied to high- speed civil transport configuration, subsonic transports, and supersonic fighters.

1997-01-01

172

Energy efficient aircraft engines  

NASA Technical Reports Server (NTRS)

The three engine programs that constitute the propulsion portion of NASA's Aircraft Energy Efficiency Program are described, their status indicated, and anticipated improvements in SFC discussed. The three engine programs are (1) Engine Component Improvement--directed at current engines, (2) Energy Efficiency Engine directed at new turbofan engines, and (3) Advanced Turboprops--directed at technology for advanced turboprop--powered aircraft with cruise speeds to Mach 0.8. Unique propulsion system interactive ties to the airframe resulting from engine design features to reduce fuel consumption are discussed. Emphasis is placed on the advanced turboprop since it offers the largest potential fuel savings of the three propulsion programs and also has the strongest interactive ties to the airframe.

Chamberlin, R.; Miller, B.

1979-01-01

173

X-29: Research Aircraft  

NASA Technical Reports Server (NTRS)

A preliminary look at the Ames Dryden Flight Research Center in the context of the X-29 aircraft is provided. The uses of the X-29's 30 deg forward swept wing are examined. The video highlights the historical development of the forward swept wing, and its unique blend of speed, agility, and slow flight potential. The central optimization of the wing, the forward canard, and the rear flaps by an onboard flight computer is also described.

1991-01-01

174

Slotted Aircraft Wing  

NASA Technical Reports Server (NTRS)

A swept aircraft wing includes a leading airfoil element and a trailing airfoil element. At least one full-span slot is defined by the wing during at least one transonic condition of the wing. The full-span slot allows a portion of the air flowing along the lower surface of the leading airfoil element to split and flow over the upper surface of the trailing airfoil element so as to achieve a performance improvement in the transonic condition.

McLean, James D. (Inventor); Witkowski, David P. (Inventor); Campbell, Richard L. (Inventor)

2006-01-01

175

Electrical Thermometers for Aircraft  

NASA Technical Reports Server (NTRS)

Electrical thermometers commonly used on aircraft are the thermoelectric type for measuring engine-cylinder temperatures, the resistance type for measuring air temperatures, and the superheat meters of thermoelectric and resistance types for use on airships. These instruments are described and their advantages and disadvantages enumerated. Methods of testing these instruments and the performance to be expected from each are discussed. The field testing of engine-cylinder thermometers is treated in detail.

Peterson, John B; Womack, S H J

1937-01-01

176

Aircraft radar echoes characterization  

NASA Astrophysics Data System (ADS)

Electromagnetic wave diffraction and reflection theories enable prediction of most of the effects generated by radar echoes on aircraft. However, it is difficult to modelize some complex effects originating in canopies, radomes and cavities. In order to supplement the present theoretical knowledge by experimental results obtained on actual targets, ONERA has developed a novel analysis method allowing the generation of radar images. This method provides an efficient working tool to assist in defining radar wise discrete aerial targets.

Pouit, C.

1980-04-01

177

Mission management aircraft operations manual  

NASA Technical Reports Server (NTRS)

This manual prescribes the NASA mission management aircraft program and provides policies and criteria for the safe and economical operation, maintenance, and inspection of NASA mission management aircraft. The operation of NASA mission management aircraft is based on the concept that safety has the highest priority. Operations involving unwarranted risks will not be tolerated. NASA mission management aircraft will be designated by the Associate Administrator for Management Systems and Facilities. NASA mission management aircraft are public aircraft as defined by the Federal Aviation Act of 1958. Maintenance standards, as a minimum, will meet those required for retention of Federal Aviation Administration (FAA) airworthiness certification. Federal Aviation Regulation Part 91, Subparts A and B, will apply except when requirements of this manual are more restrictive.

1992-01-01

178

Advanced aircraft for atmospheric research  

NASA Technical Reports Server (NTRS)

The development of aircraft for high-altitude research is described in terms of program objectives and environmental, technological limitations, and the work on the Perseus A aircraft. The need for these advanced aircraft is proposed in relation to atmospheric science issues such as greenhouse trapping, the dynamics of tropical cyclones, and stratospheric ozone. The implications of the study on aircraft design requirements is addressed with attention given to the basic categories of high-altitude, long-range, long-duration, and nap-of-the-earth aircraft. A strategy is delineated for a platform that permits unique stratospheric measurements and is a step toward a more advanced aircraft. The goal of Perseus A is to carry scientific air sampling payloads weighing at least 50 kg to altitudes of more than 25 km. The airfoils are designed for low Reynolds numbers, the structural weight is very low, and the closed-cycle power plant runs on liquid oxygen.

Russell, P.; Wegener, S.; Langford, J.; Anderson, J.; Lux, D.; Hall, D. W.

1991-01-01

179

Aircraft cockpit vision: Math model  

NASA Technical Reports Server (NTRS)

A mathematical model was developed to describe the field of vision of a pilot seated in an aircraft. Given the position and orientation of the aircraft, along with the geometrical configuration of its windows, and the location of an object, the model determines whether the object would be within the pilot's external vision envelope provided by the aircraft's windows. The computer program using this model was implemented and is described.

Bashir, J.; Singh, R. P.

1975-01-01

180

The Typical General Aviation Aircraft  

NASA Technical Reports Server (NTRS)

The reliability of General Aviation aircraft is unknown. In order to "assist the development of future GA reliability and safety requirements", a reliability study needs to be performed. Before any studies on General Aviation aircraft reliability begins, a definition of a typical aircraft that encompasses most of the general aviation characteristics needs to be defined. In this report, not only is the typical general aviation aircraft defined for the purpose of the follow-on reliability study, but it is also separated, or "sifted" into several different categories where individual analysis can be performed on the reasonably independent systems. In this study, the typical General Aviation aircraft is a four-place, single engine piston, all aluminum fixed-wing certified aircraft with a fixed tricycle landing gear and a cable operated flight control system. The system breakdown of a GA aircraft "sifts" the aircraft systems and components into five categories: Powerplant, Airframe, Aircraft Control Systems, Cockpit Instrumentation Systems, and the Electrical Systems. This breakdown was performed along the lines of a failure of the system. Any component that caused a system to fail was considered a part of that system.

Turnbull, Andrew

1999-01-01

181

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

182

X-29 aircraft takeoff  

NASA Technical Reports Server (NTRS)

Two X-29 aircraft, featuring one of the most unusual designs in aviation history, were flown at the NASA Dryden Flight Research Center, Edwards, Calif., as technology demonstrators to investigate a host of advanced concepts and technologies. This movie clip runs 26 seconds and begins with a rear view of the X-29 in full afterburner at brake release, then a chase plane shot as it rotates off the runway beginning a rapid climb and finally an air-to-air view of the tail as the chase plane with the camera moves from right to left.

1989-01-01

183

Slotted Aircraft Wing  

NASA Technical Reports Server (NTRS)

An aircraft wing includes a leading airfoil element and a trailing airfoil element. At least one slot is defined by the wing during at least one transonic condition of the wing. The slot may either extend spanwise along only a portion of the wingspan, or it may extend spanwise along the entire wingspan. In either case, the slot allows a portion of the air flowing along the lower surface of the leading airfoil element to split and flow over the upper surface of the trailing airfoil element so as to achieve a performance improvement in the transonic condition.

Vassberg, John C. (Inventor); Gea, Lie-Mine (Inventor); McLean, James D. (Inventor); Witowski, David P. (Inventor); Krist, Steven E. (Inventor); Campbell, Richard L. (Inventor)

2006-01-01

184

14 CFR 252.13 - Small aircraft.  

Code of Federal Regulations, 2010 CFR

...DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS SMOKING ABOARD AIRCRAFT § 252.13 Small aircraft. Air carriers shall prohibit smoking on aircraft designed to have a passenger capacity of 30 or fewer seats....

2010-01-01

185

14 CFR 252.13 - Small aircraft.  

Code of Federal Regulations, 2011 CFR

...DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS SMOKING ABOARD AIRCRAFT § 252.13 Small aircraft. Air carriers shall prohibit smoking on aircraft designed to have a passenger capacity of 30 or fewer seats....

2011-01-01

186

14 CFR 34.6 - Aircraft safety.  

Code of Federal Regulations, 2014 CFR

...2014-01-01 2014-01-01 false Aircraft safety. 34.6 Section 34.6 ...DEPARTMENT OF TRANSPORTATION AIRCRAFT FUEL VENTING AND EXHAUST EMISSION...General Provisions § 34.6 Aircraft safety. (a) The provisions...

2014-01-01

187

14 CFR 34.6 - Aircraft safety.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 2012-01-01 false Aircraft safety. 34.6 Section 34.6 ...DEPARTMENT OF TRANSPORTATION AIRCRAFT FUEL VENTING AND EXHAUST EMISSION...General Provisions § 34.6 Aircraft safety. (a) The provisions...

2012-01-01

188

14 CFR 34.6 - Aircraft safety.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 2011-01-01 false Aircraft safety. 34.6 Section 34.6 ...DEPARTMENT OF TRANSPORTATION AIRCRAFT FUEL VENTING AND EXHAUST EMISSION...General Provisions § 34.6 Aircraft safety. (a) The provisions...

2011-01-01

189

14 CFR 34.6 - Aircraft safety.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Aircraft safety. 34.6 Section 34.6 ...DEPARTMENT OF TRANSPORTATION AIRCRAFT FUEL VENTING AND EXHAUST EMISSION...General Provisions § 34.6 Aircraft safety. (a) The provisions...

2010-01-01

190

14 CFR 34.6 - Aircraft safety.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 2013-01-01 false Aircraft safety. 34.6 Section 34.6 ...DEPARTMENT OF TRANSPORTATION AIRCRAFT FUEL VENTING AND EXHAUST EMISSION...General Provisions § 34.6 Aircraft safety. (a) The provisions...

2013-01-01

191

78 FR 67309 - Earth Stations Aboard Aircraft  

Federal Register 2010, 2011, 2012, 2013, 2014

...Docket Nos. 12-376, FCC 12-161] Earth Stations Aboard Aircraft AGENCY: Federal...collection associated with the Commission's Earth Station Aboard Aircraft, Report and Order...adopted licensing and service rules for Earth Stations Aboard Aircraft (ESAA)...

2013-11-12

192

14 CFR 21.127 - Tests: aircraft.  

Code of Federal Regulations, 2014 CFR

...2014-01-01 2014-01-01 false Tests: aircraft. 21.127 Section 21.127 Aeronautics...ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT CERTIFICATION PROCEDURES FOR PRODUCTS...Type Certificate § 21.127 Tests: aircraft. (a) Each person...

2014-01-01

193

14 CFR 21.127 - Tests: aircraft.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Tests: aircraft. 21.127 Section 21.127 Aeronautics...ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT CERTIFICATION PROCEDURES FOR PRODUCTS...Certificate Only § 21.127 Tests: aircraft. (a) Each person...

2010-01-01

194

14 CFR 21.127 - Tests: aircraft.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 2011-01-01 false Tests: aircraft. 21.127 Section 21.127 Aeronautics...ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT CERTIFICATION PROCEDURES FOR PRODUCTS...Certificate Only § 21.127 Tests: aircraft. (a) Each person...

2011-01-01

195

14 CFR 21.127 - Tests: aircraft.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 2013-01-01 false Tests: aircraft. 21.127 Section 21.127 Aeronautics...ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT CERTIFICATION PROCEDURES FOR PRODUCTS...Type Certificate § 21.127 Tests: aircraft. (a) Each person...

2013-01-01

196

19 CFR 122.42 - Aircraft entry.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Aircraft entry. 122.42 Section 122.42...TREASURY AIR COMMERCE REGULATIONS Aircraft Entry and Entry Documents; Electronic...Non-Crew Members Onboard Commercial Aircraft Arriving In, Continuing Within,...

2013-04-01

197

19 CFR 122.42 - Aircraft entry.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Aircraft entry. 122.42 Section 122.42...TREASURY AIR COMMERCE REGULATIONS Aircraft Entry and Entry Documents; Electronic...Non-Crew Members Onboard Commercial Aircraft Arriving In, Continuing Within,...

2011-04-01

198

19 CFR 122.42 - Aircraft entry.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Aircraft entry. 122.42 Section 122.42...TREASURY AIR COMMERCE REGULATIONS Aircraft Entry and Entry Documents; Electronic...Non-Crew Members Onboard Commercial Aircraft Arriving In, Continuing Within,...

2010-04-01

199

19 CFR 122.42 - Aircraft entry.  

Code of Federal Regulations, 2014 CFR

...2014-04-01 2014-04-01 false Aircraft entry. 122.42 Section 122.42...TREASURY AIR COMMERCE REGULATIONS Aircraft Entry and Entry Documents; Electronic...Non-Crew Members Onboard Commercial Aircraft Arriving In, Continuing Within,...

2014-04-01

200

14 CFR 21.127 - Tests: aircraft.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 2012-01-01 false Tests: aircraft. 21.127 Section 21.127 Aeronautics...ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT CERTIFICATION PROCEDURES FOR PRODUCTS...Type Certificate § 21.127 Tests: aircraft. (a) Each person...

2012-01-01

201

19 CFR 122.42 - Aircraft entry.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Aircraft entry. 122.42 Section 122.42...TREASURY AIR COMMERCE REGULATIONS Aircraft Entry and Entry Documents; Electronic...Non-Crew Members Onboard Commercial Aircraft Arriving In, Continuing Within,...

2012-04-01

202

Dumbo heavy lifter aircraft  

NASA Technical Reports Server (NTRS)

The world is rapidly changing from one with two military superpowers, with which most countries were aligned, to one with many smaller military powers. In this environment, the United States cannot depend on the availability of operating bases from which to respond to crises requiring military intervention. Several studies (e.g. the SAB Global Reach, Global Power Study) have indicated an increased need to be able to rapidly transport large numbers of troops and equipment from the continental United States to potential trouble spots throughout the world. To this end, a request for proposals (RFP) for the concept design of a large aircraft capable of 'projecting' a significant military force without reliance on surface transportation was developed. These design requirements are: minimum payload of 400,000 pounds at 2.5 g maneuver load factor; minimum unfueled range of 6,000 nautical miles; and aircraft must operate from existing domestic air bases and use existing airbases or sites of opportunity at the destination.

Riester, Peter; Ellis, Colleen; Wagner, Michael; Orren, Scott; Smith, Byron; Skelly, Michael; Zgraggen, Craig; Webber, Matt

1992-01-01

203

Fuel conservative aircraft engine technology  

NASA Technical Reports Server (NTRS)

Technology developments for more fuel-efficiency subsonic transport aircraft are reported. Three major propulsion projects were considered: (1) engine component improvement - directed at current engines; (2) energy efficient engine - directed at new turbofan engines; and (3) advanced turboprops - directed at technology for advanced turboprop-powered aircraft. Each project is reviewed and some of the technologies and recent accomplishments are described.

Nored, D. L.

1978-01-01

204

Research developments for aircraft safety  

NASA Technical Reports Server (NTRS)

The paper deals with an aviation safety technology program, whose objective is to provide technology for near-term application to civil transport aircraft and for designing the next generation of advanced transports. The influence of research and development efforts on current safety levels and aircraft operating efficiency is examined.

Hodge, K. E.

1980-01-01

205

Ball lightning risk to aircraft  

Microsoft Academic Search

Lightning is a rare but regular phenomenon for air traffic. Aircraft are designed to withstand lightning strikes. Research on lightning and aircraft can be called detailed and effective. In the last 57 years, 18 reported lightning aviation disasters with a fatality figure of at least 714 persons occurred. For comparison, the last JACDEC ten-year average fatality figure was 857. The

R. Doe; A. Keul

2009-01-01

206

Steam Power Plants in Aircraft  

NASA Technical Reports Server (NTRS)

The employment of steam power plants in aircraft has been frequently proposed. Arguments pro and con have appeared in many journals. It is the purpose of this paper to make a brief analysis of the proposal from the broad general viewpoint of aircraft power plants. Any such analysis may be general or detailed.

Wilson, E E

1926-01-01

207

Electronically steerable antenna for aircraft  

Microsoft Academic Search

The design of an electronically steerable medium gain antenna for aircraft able to provide voice communication via satellite is presented. The antenna consists of 5 radiating facets and the coverages achieved, including the effect of the aircraft fuselage, are based on the experimental results obtained with the actual components of the beam forming network (switches, phase shifters, power dividers) and

J. Barbero; M. L. Hernanz; C. Martin; J. Vassallo; B. Hedge

1991-01-01

208

Controllability properties for aircraft formations  

Microsoft Academic Search

This paper studies the controllability of formations of n identical aircraft maintaining constant distances. Aircraft are modeled as a planar kinematic system with constant velocity and curvature bounds. The challenges of achieving controllability of such system are that it is an affine system with drift and its admissible controls are determined by its configuration variables. We begin with the study

Huifang Wang; Lucia Pallottino; Antonio Bicchi

2010-01-01

209

Tilt Rotor Aircraft Aeroacoustics  

NASA Technical Reports Server (NTRS)

A fleet of civil tilt rotor transports offers a means of reducing airport congestion and point-to-point travel time. The speed, range, and fuel economy of these aircraft, along with their efficient use of vertiport area, make them good candidates for short-to-medium range civil transport. However, to be successfully integrated into the civilian community, the tilt rotor must be perceived as a quiet, safe, and economical mode of transportation that does not harm the environment. In particular, noise impact has been identified as a possible barrier to the civil tilt rotor. Along with rotor conversion-mode flight, and blade-vortex interaction noise during descent, hover mode is a noise problem for tilt rotor operations. In the present research, tilt rotor hover aeroacoustics have been studied analytically, experimentally, and computationally. Various papers on the subject were published as noted in the list of publications. More recently, experimental measurements were made on a 1/12.5 scale model of the XV-15 in hover and analyses of this data and extrapolations to full scale were also carried out. A dimensional analysis showed that the model was a good aeroacoustic approximation to the full-scale aircraft, and scale factors were derived to extrapolate the model measurements to the full-scale XV-15. The experimental measurements included helium bubble flow visualization, silk tuft flow visualization, 2-component hot wire anemometry, 7-hole pressure probe measurements, vorticity measurements, and outdoor far field acoustic measurements. The hot wire measurements were used to estimate the turbulence statistics of the flow field into the rotors, such as length scales, velocity scales, dissipation, and turbulence intermittency. Several different configurations of the model were tested: (1) standard configurations (single isolated rotor, two rotors without the aircraft, standard tilt rotor configuration); (2) flow control devices (the 'plate', the 'diagonal fences'); (3) basic configuration changes (increasing the rotor/rotor spacing, reducing the rotor plane/wing clearance. operating the rotors out of phase). Also, an approximation to Sikorsky's Variable Diameter Tilt Rotor (VDTR) configuration was tested, and some flow measurements were made on a semi-span configuration of the model. Acoustic predictions were made using LOWSON.M, a Mathematica code Mean aerodynamic models were developed based on hover performance predictions from HOVER.FOR. This hover prediction code used blade element theory for the aerodynamics, and Prandtl's Vortex theory to model the wake, along with empirical formulas for the effects of Reynolds number, Mach number, and stall. Aerodynamic models were developed from 7-hole pressure probe measurements of the mean velocity into the model rotors.

George, Albert R.

1996-01-01

210

Aircraft vortex marking program  

NASA Technical Reports Server (NTRS)

A simple, reliable device for identifying atmospheric vortices, principally as generated by in-flight aircraft and with emphasis on the use of nonpolluting aerosols for marking by injection into such vortex (-ices) is presented. The refractive index and droplet size were determined from an analysis of aerosol optical and transport properties as the most significant parameters in effecting vortex optimum light scattering (for visual sighting) and visual persistency of at least 300 sec. The analysis also showed that a steam-ejected tetraethylene glycol aerosol with droplet size near 1 micron and refractive index of approximately 1.45 could be a promising candidate for vortex marking. A marking aerosol was successfully generated with the steam-tetraethylene glycol mixture from breadboard system hardware. A compact 25 lb/f thrust (nominal) H2O2 rocket chamber was the key component of the system which produced the required steam by catalytic decomposition of the supplied H2O2.

Pompa, M. F.

1979-01-01

211

Aircraft radar antennas  

NASA Astrophysics Data System (ADS)

Many changes have taken place in airborne radar antennas since their beginnings over forty years ago. A brief historical review of the advances in technology is presented, from mechanically scanned reflectors to modern multiple function phased arrays. However, emphasis is not on history but on the state-of-the-art technology and trends for future airborne radar systems. The status of rotating surveillance antennas is illustrated by the AN/APY-1 Airborne Warning and Control System (AWACS) slotted waveguide array, which achieved a significant breakthrough in sidelobe suppression. Gimballed flat plate arrays in nose radomes are typified by the AN/APG-66 (F-16) antenna. Multifunction phased arrays are presented by the Electronically Agile Radar (EAR) antenna, which has achieved significant advances in performance versatility and reliability. Trends toward active aperture, adaptive, and digital beamforming arrays are briefly discussed. Antennas for future aircraft radar systems must provide multiple functions in less aperture space, and must perform more reliably.

Schrank, Helmut E.

1987-04-01

212

Alternative aircraft fuels  

NASA Technical Reports Server (NTRS)

In connection with the anticipated impossibility to provide on a long-term basis liquid fuels derived from petroleum, an investigation has been conducted with the objective to assess the suitability of jet fuels made from oil shale and coal and to develop a data base which will allow optimization of future fuel characteristics, taking energy efficiency of manufacture and the tradeoffs in aircraft and engine design into account. The properties of future aviation fuels are examined and proposed solutions to problems of alternative fuels are discussed. Attention is given to the refining of jet fuel to current specifications, the control of fuel thermal stability, and combustor technology for use of broad specification fuels. The first solution is to continue to develop the necessary technology at the refinery to produce specification jet fuels regardless of the crude source.

Longwell, J. P.; Grobman, J.

1978-01-01

213

Aircraft control system  

NASA Technical Reports Server (NTRS)

A solar rechargeable, long-duration, span-loaded flying wing, having no fuselage or rudder. Having a two-hundred foot wingspan that mounts photovoltaic cells on most all of the wing's top surface, the aircraft uses only differential thrust of its eight propellers to turn, pitch and yaw. The wing is configured to deform under flight loads to position the propellers such that the control can be achieved. Each of five segments of the wing has one or more motors and photovoltaic arrays, and produces its own lift independent of the other segments, to avoid loading them. Five two-sided photovoltaic arrays, in all, are mounted on the wing, and receive photovoltaic energy both incident on top of the wing, and which is incident also from below, through a bottom, transparent surface.

Lisoski, Derek L. (Inventor); Kendall, Greg T. (Inventor)

2007-01-01

214

41 CFR 102-33.240 - What must we consider before disposing of aircraft and aircraft parts?  

Code of Federal Regulations, 2013 CFR

...false What must we consider before disposing of aircraft and aircraft parts? 102-33.240 Section 102-33.240...PERSONAL PROPERTY 33-MANAGEMENT OF GOVERNMENT AIRCRAFT Disposing of Government Aircraft and Aircraft...

2013-07-01

215

41 CFR 102-33.240 - What must we consider before disposing of aircraft and aircraft parts?  

Code of Federal Regulations, 2011 CFR

...false What must we consider before disposing of aircraft and aircraft parts? 102-33.240 Section 102-33.240...PERSONAL PROPERTY 33-MANAGEMENT OF GOVERNMENT AIRCRAFT Disposing of Government Aircraft and Aircraft...

2011-01-01

216

41 CFR 102-33.240 - What must we consider before disposing of aircraft and aircraft parts?  

Code of Federal Regulations, 2010 CFR

...false What must we consider before disposing of aircraft and aircraft parts? 102-33.240 Section 102-33.240...PERSONAL PROPERTY 33-MANAGEMENT OF GOVERNMENT AIRCRAFT Disposing of Government Aircraft and Aircraft...

2010-07-01

217

41 CFR 102-33.240 - What must we consider before disposing of aircraft and aircraft parts?  

Code of Federal Regulations, 2012 CFR

...false What must we consider before disposing of aircraft and aircraft parts? 102-33.240 Section 102-33.240...PERSONAL PROPERTY 33-MANAGEMENT OF GOVERNMENT AIRCRAFT Disposing of Government Aircraft and Aircraft...

2012-01-01

218

41 CFR 102-33.240 - What must we consider before disposing of aircraft and aircraft parts?  

Code of Federal Regulations, 2014 CFR

...false What must we consider before disposing of aircraft and aircraft parts? 102-33.240 Section 102-33.240...PERSONAL PROPERTY 33-MANAGEMENT OF GOVERNMENT AIRCRAFT Disposing of Government Aircraft and Aircraft...

2014-01-01

219

Multibody aircraft study, volume 1  

NASA Technical Reports Server (NTRS)

The potential benefits of a multibody aircraft when compared to a single body aircraft are presented. The analyses consist principally of a detailed point design analysis of three multibody and one single body aircraft, based on a selected payload of 350,000 kg (771,618 lb), for final aircraft definitions; sensitivity studies to evaluate the effects of variations in payload, wing semispan body locations, and fuel price; recommendations as to the research and technology requirements needed to validate the multibody concept. Two, two body, one, three body, and one single body aircraft were finalized for the selected payload, with DOC being the prime figure of merit. When compared to the single body, the multibody aircraft showed a reduction in DOC by as much as 11.3 percent. Operating weight was reduced up to 14 percent, and fly away cost reductions ranged from 8.6 to 13.4 percent. Weight reduction, hence cost, of the multibody aircraft resulted primarily from the wing bending relief afforded by the bodies being located outboard on the wing.

Moore, J. W.; Craven, E. P.; Farmer, B. T.; Honrath, J. F.; Stephens, R. E.; Bronson, C. E., Jr.; Meyer, R. T.; Hogue, J. H.

1982-01-01

220

NASA Aircraft Controls Research, 1983  

NASA Technical Reports Server (NTRS)

The workshop consisted of 24 technical presentations on various aspects of aircraft controls, ranging from the theoretical development of control laws to the evaluation of new controls technology in flight test vehicles. A special report on the status of foreign aircraft technology and a panel session with seven representatives from organizations which use aircraft controls technology were also included. The controls research needs and opportunities for the future as well as the role envisioned for NASA in that research were addressed. Input from the panel and response to the workshop presentations will be used by NASA in developing future programs.

Beasley, G. P. (compiler)

1984-01-01

221

DICHLORVOS VAPOUR DISINSECTION OF AIRCRAFT.  

PubMed

The authors describe the testing of an automatic aircraft disinsection system permanently installed on a commercial DC-6B passenger aircraft. An air-compressor forces ambient cabin air, partially saturated with dichlorvos vapour at a set concentration, through the cabin, cockpit and baggage compartments of the aircraft for 30 minutes. Insecticide concentrations and insect mortality were observed in post-overhaul check flights, and insect mortality and passenger reactions were observed on scheduled flights between Miami, Florida, and Nassau, Bahamas.The results showed satisfactory biological efficiency. The passengers were unaware of the disinsection process and showed no signs of discomfort. PMID:14310904

JENSEN, J A; FLURY, V P; SCHOOF, H F

1965-01-01

222

Insecticidal vapours for aircraft disinsection.  

PubMed

A general discussion of the problem of aircraft disinsection is presented. The weaknesses of the present aerosol method, the limitations imposed by airline operators, government officials, passengers, and others, and the potential value of insecticidal vapours as a means of aircraft disinsection are discussed. An apparatus is described for screening insecticides for their vapour toxicity to houseflies and mosquitos. This apparatus led to the discovery of DDVP (O,O-dimethyl-2,2-dichlorovinyl phosphate) and its remarkable vapour toxicity to insects, and to the subsequent studies of its potential use in the vapour state for aircraft disinsection. PMID:13733751

PEARCE, G W; SCHOOF, H F; QUARTERMAN, K D

1961-01-01

223

Dichlorvos vapour disinsection of aircraft  

PubMed Central

The authors describe the testing of an automatic aircraft disinsection system permanently installed on a commercial DC-6B passenger aircraft. An air-compressor forces ambient cabin air, partially saturated with dichlorvos vapour at a set concentration, through the cabin, cockpit and baggage compartments of the aircraft for 30 minutes. Insecticide concentrations and insect mortality were observed in post-overhaul check flights, and insect mortality and passenger reactions were observed on scheduled flights between Miami, Florida, and Nassau, Bahamas. The results showed satisfactory biological efficiency. The passengers were unaware of the disinsection process and showed no signs of discomfort. ImagesFIG. 1FIG. 2FIG. 3 PMID:14310904

Jensen, Jens A.; Flury, Vincent P.; Schoof, Herbert F.

1965-01-01

224

Insecticidal Vapours for Aircraft Disinsection*  

PubMed Central

A general discussion of the problem of aircraft disinsection is presented. The weaknesses of the present aerosol method, the limitations imposed by airline operators, government officials, passengers, and others, and the potential value of insecticidal vapours as a means of aircraft disinsection are discussed. An apparatus is described for screening insecticides for their vapour toxicity to houseflies and mosquitos. This apparatus led to the discovery of DDVP (O,O-dimethyl-2,2-dichlorovinyl phosphate) and its remarkable vapour toxicity to insects, and to the subsequent studies of its potential use in the vapour state for aircraft disinsection. PMID:13733751

Pearce, G. W.; Schoof, H. F.; Quarterman, K. D.

1961-01-01

225

40 CFR 87.6 - Aircraft safety.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Aircraft safety. 87.6 Section 87.6 Protection...CONTROL OF AIR POLLUTION FROM AIRCRAFT AND AIRCRAFT ENGINES General Provisions § 87.6 Aircraft safety. The provisions of this part...

2011-07-01

226

40 CFR 87.6 - Aircraft safety.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Aircraft safety. 87.6 Section 87.6 Protection...CONTROL OF AIR POLLUTION FROM AIRCRAFT AND AIRCRAFT ENGINES General Provisions § 87.6 Aircraft safety. The provisions of this part...

2010-07-01

227

Instrumentation for Unmanned Aircraft Systems (UAS)  

E-print Network

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

Delene, David J.

228

Wet runways. [aircraft landing and directional control  

NASA Technical Reports Server (NTRS)

Aircraft stopping and directional control performance on wet runways is discussed. The major elements affecting tire/ground traction developed by jet transport aircraft are identified and described in terms of atmospheric, pavement, tire, aircraft system and pilot performance factors or parameters. Research results are summarized, and means for improving or restoring tire traction/aircraft performance on wet runways are discussed.

Horne, W. B.

1975-01-01

229

Real-time aircraft turnaround operations manager  

Microsoft Academic Search

Aircraft turnaround operations are the activities conducted to prepare an inbound aircraft at an airport for a following outbound flight that is scheduled for the same aircraft. The activities of aircraft turnaround operations include both the inbound and outbound exchanges of passengers, crew, catering services, cargo and baggage handling. Hence, appears the importance of following up on all activities done

M. Abd Allah Makhloof; M. Elsayed Waheed; Usama A. El-Raouf Badawi

2012-01-01

230

Progress in aircraft design since 1903  

NASA Technical Reports Server (NTRS)

Significant developments in aviation history are documented to show the advancements in aircraft design which have taken place since 1903. Each aircraft is identified according to the manufacturer, powerplant, dimensions, normal weight, and typical performance. A narrative summary of the major accomplishments of the aircraft is provided. Photographs of each aircraft are included.

1974-01-01

231

Scheduling Aircraft Landings The Dynamic Case  

E-print Network

Scheduling Aircraft Landings The Dynamic Case Master Thesis April 2007 Supervisor: Jens Clausen #12;Abstract This Master Theses is about solving the aircraft landing problem dynamically. Given an original landing schedule for the incoming aircraft this schedule are rescheduled whenever an aircraft

232

AIRCRAFT CONTROL USING FLATNESS Philippe Martin  

E-print Network

AIRCRAFT CONTROL USING FLATNESS Philippe Martin £ £ Centre Automatique et Syst`emes, ´Ecole des: A control law for an aircraft is presented. It is valid on the whole flight envelope and able to track any approximating the real aircraft and the use of time scales. Keywords: Aircraft control, nonlinear control

Paris-Sud XI, Université de

233

Turboprop Cargo Aircraft Systems study, phase 1  

NASA Technical Reports Server (NTRS)

The effects of advanced propellers (propfan) on aircraft direct operating costs, fuel consumption, and noiseprints were determined. A comparison of three aircraft selected from the results with competitive turbofan aircraft shows that advanced turboprop aircraft offer these potential benefits, relative to advanced turbofan aircraft: 21 percent fuel saving, 26 percent higher fuel efficiency, 15 percent lower DOCs, and 25 percent shorter field lengths. Fuel consumption for the turboprop is nearly 40 percent less than for current commercial turbofan aircraft. Aircraft with both types of propulsion satisfy current federal noise regulations. Advanced turboprop aircraft have smaller noiseprints at 90 EPNdB than advanced turbofan aircraft, but large noiseprints at 70 and 80 EPNdB levels, which are usually suggested as quietness goals. Accelerated development of advanced turboprops is strongly recommended to permit early attainment of the potential fuel saving. Several areas of work are identified which may produce quieter turboprop aircraft.

Muehlbauer, J. C.; Hewell, J. G., Jr.; Lindenbaum, S. P.; Randall, C. C.; Searle, N.; Stone, F. R., Jr.

1980-01-01

234

Can advanced technology improve future commuter aircraft  

NASA Technical Reports Server (NTRS)

The short-haul service abandoned by the trunk and local airlines is being picked up by the commuter airlines using small turboprop-powered aircraft. Most of the existing small transport aircraft currently available represent a relatively old technology level. However, several manufacturers have initiated the development of new or improved commuter transport aircraft. These aircraft are relatively conservative in terms of technology. An examination is conducted of advanced technology to identify those technologies that, if developed, would provide the largest improvements for future generations of these aircraft. Attention is given to commuter aircraft operating cost, aerodynamics, structures and materials, propulsion, aircraft systems, and technology integration. It is found that advanced technology can improve future commuter aircraft and that the largest of these improvements will come from the synergistic combination of technological advances in all of the aircraft disciplines. The most important goals are related to improved fuel efficiency and increased aircraft productivity.

Williams, L. J.; Snow, D. B.

1981-01-01

235

Unmanned Aircraft: A Pilot's Perspective  

NASA Technical Reports Server (NTRS)

This slide presentation reviews some of the challenges of "piloting" a unmanned aircraft. The topic include the pilot-vehicle interact design, the concept of pilot/operator, and role of NASA's Ikhana UAS in the western states fire mission.

Pestana, Mark E.

2010-01-01

236

Electromagnetic Interference In New Aircraft  

NASA Technical Reports Server (NTRS)

Report reviews plans to develop tests and standards to ensure that digital avionics systems in new civil aircraft immune to electromagnetic interference (EMI). Updated standards reflect more severe environment and vulnerabilities of modern avionics.

Larsen, William E.

1991-01-01

237

Aircraft accidents : method of analysis  

NASA Technical Reports Server (NTRS)

This report on a method of analysis of aircraft accidents has been prepared by a special committee on the nomenclature, subdivision, and classification of aircraft accidents organized by the National Advisory Committee for Aeronautics in response to a request dated February 18, 1928, from the Air Coordination Committee consisting of the Assistant Secretaries for Aeronautics in the Departments of War, Navy, and Commerce. The work was undertaken in recognition of the difficulty of drawing correct conclusions from efforts to analyze and compare reports of aircraft accidents prepared by different organizations using different classifications and definitions. The air coordination committee's request was made "in order that practices used may henceforth conform to a standard and be universally comparable." the purpose of the special committee therefore was to prepare a basis for the classification and comparison of aircraft accidents, both civil and military. (author)

1929-01-01

238

Aircraft Cabin Environmental Quality Sensors  

E-print Network

cabin air through high efficiency particulate air (HEPA) filterscabin air. The GAO learned that 85% used HEPA filters. Afilter. On most large aircraft, recirculation reduces exposure to particulate air contaminants because the cabin

Gundel, Lara

2010-01-01

239

Composite components on commercial aircraft  

NASA Technical Reports Server (NTRS)

Commercial aircraft manufacturers are making production commitments to composite structure for future aircraft and modifications to current production aircraft. Flight service programs with advanced composites sponsored by NASA during the past 10 years are described. Approximately 2.5 million total composite component flight hours have been accumulated since 1970 on both commercial transports and helicopters. Design concepts with significant mass savings were developed, appropriate inspection and maintenance procedures were established, and satisfactory service was achieved for the various composite components. A major NASA/U.S. industry technology program to reduce fuel consumption of commercial transport aircraft through the use of advanced composites was undertaken. Ground and flight environmental effects on the composite materials used in the flight service programs supplement the flight service evaluation.

Dexter, H. B.

1980-01-01

240

Aircraft icing research at NASA  

NASA Technical Reports Server (NTRS)

Research activity is described for: ice protection systems, icing instrumentation, experimental methods, analytical modeling for the above, and in flight research. The renewed interest in aircraft icing has come about because of the new need for All-Weather Helicopters and General Aviation aircraft. Because of increased fuel costs, tomorrow's Commercial Transport aircraft will also require new types of ice protection systems and better estimates of the aeropenalties caused by ice on unprotected surfaces. The physics of aircraft icing is very similar to the icing that occurs on ground structures and structures at sea; all involve droplets that freeze on the surfaces because of the cold air. Therefore all icing research groups will benefit greatly by sharing their research information.

Reinmann, J. J.; Shaw, R. J.; Olsen, W. A., Jr.

1982-01-01

241

Qualification needs for advanced integrated aircraft  

NASA Technical Reports Server (NTRS)

In an effort to achieve maximum aircraft performance, designers are integrating aircraft systems. The characteristics of aerodynamics, vehicle structure, and propulsion systems are being integrated and controlled through embedded, often flight critical, electronic systems. The qualification needs for such highly integrated aircraft systems are addressed. Based on flight experience with research aircraft, a set of test capabilities is described which allows for complete and efficient qualification of advanced integrated aircraft.

Mackall, D. A.

1985-01-01

242

X-29 - views of aircraft  

NASA Technical Reports Server (NTRS)

Two X-29 aircraft, featuring one of the most unusual designs in aviation history, were flown at the NASA Dryden Flight Research Center, Edwards, Calif., as technology demonstrators to investigate a host of advanced concepts and technologies. In this 29-second film clip the camera pans along the aircraft from nose to tail and then air-to-air as the shot sweeps from beside the X-29 around to the front.

1989-01-01

243

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

244

Hydrogen aircraft and airport safety  

Microsoft Academic Search

Hydrogen will be used as aviation fuel in the foreseeable future. First flight tests with a hydrogen demonstrator aircraft, currently under investigation in the scope of the German-Russian Cryoplane project, are scheduled for 1999. Regular service with regional aircraft may begin around 2005, followed by larger Airbus-type airliners around 2010–2015. The fuel storage aboard such airliners will be of the

N. Rostek; E. Behrend; H.-W. Pohl

1997-01-01

245

Jet aircraft hydrocarbon fuels technology  

NASA Technical Reports Server (NTRS)

A broad specification, referee fuel was proposed for research and development. This fuel has a lower, closely specified hydrogen content and higher final boiling point and freezing point than ASTM Jet A. The workshop recommended various priority items for fuel research and development. Key items include prediction of tradeoffs among fuel refining, distribution, and aircraft operating costs; combustor liner temperature and emissions studies; and practical simulator investigations of the effect of high freezing point and low thermal stability fuels on aircraft fuel systems.

Longwell, J. P. (editor)

1978-01-01

246

CAATER: Merlin IV, Aircraft Facility  

NASA Astrophysics Data System (ADS)

Merlin IV , is owned , operated and managed by Météo France. This aircraft has been especially modified and equipped for atmospheric research together with staff and infrastructure needed to support its use. Merlin IV , entirely dedicated to atmospheric research, is a versatile flying laboratory offering several scientific configurations: basic meteorological instrumentation, turbulent flux equipment, radiation measurement (Visible, Red, IR, UV, J(NO_2)) , radiance, ground temperature, microphysics sensors, in-situ and remote sensing chemistry instruments (NO-NO_2-NOy and PAN, Water Vapour ). Equipment and instrumentation can be easily installed on board through the cargo door . Within one day, configuration of the aircraft can be changed on site. Meteo France can study to install any new instrument in or on the aircraft. Real time data processing enables to visualize parameters during flights for adapting flight patterns to conditions. Access to the Merlin was offered through the EC-funded IHP-ARI contract, under a co-ordinated aircraft project (with MRF, U.K.; DLR, Germany and INSU/CNRS France) called CAATER (Co-ordinated Access to Aircraft for Transnational Environmental Research). Since 2000 access to the Merlin has been offered to 7 research groups from different EU Member States for about 10 flight hours each. A new project, with new aircraft ATR42, within the frame of an Integrated Infrastructure Initiative of the Sixth Framework Programme is currently in preparation.

Lefebvre, M.-P.; Cariolle, D.

2003-04-01

247

Variation of aircraft noise annoyance  

NASA Technical Reports Server (NTRS)

Laboratory and field studies were conducted to determine the basis for increased sensitivity of people to noise during aircraft noise studies. This change in sensitivity could be attributed to either a physiological time-of-day effect (i.e., a circadian rhythm) or simply to the total number of aircraft noise events experienced during a laboratory test period. In order to investigate the time-of-day factor, noise sensitivity measures were obtained from subjects at home with cassette tape recorders/headsets over a 24 hour period. The effect of number of aircraft noise events on noise sensitivity was investigated within a laboratory. In these tests, measures of sensitivity to noise were obtained from subjects before and after their exposure to varying numbers of aircraft noise events. The 24 hour data showed no evidence that noise sensitivity is physiologically cyclical. Consequently, these data can not explain annoyance response variation to aircraft noise tests conducted during the daytime. However, the number of aircraft noise events did influence the subject's noise sensitivity. This effect completely accounts for the systematic increase in noise sensitivity during a laboratory test period.

Dempsey, T. K.

1980-01-01

248

Fiber optics for advanced aircraft  

NASA Astrophysics Data System (ADS)

The increased use of composites makes the digital control more susceptible to electromagnetic effects. In order to provide the protection to the digital control additional shielding will be required as well as protective circuitry for the electronics. This results in increased weight and reduced reliability. The advantages that fiber optic technology provides for advanced aircraft applications is recognized. The use of optical signals to carry information between the aircraft and the control module provides immunity from contamination by electromagnetic sources as well as other important benefits such as reduced weight and volume resulting from the elimination of the shielding and the replacement of metal conductors with low weight glass fibers. In 1975 NASA began work to develop passive optical sensors for use with fiber optics in aircraft control systems. The problem now is to choose the best optical sensor concepts and evaluate them for use. In 1985 NASA and DOD entered into a joint program, Fiber Optic Control System Integration (FOCSI), to look at optical technology specifically for use in advanced aircraft systems. The results of this program are discussed. The conclusion of the study indicated that the use of fiber optic technology in advanced aircraft systems is feasible and desirable. The study pointed to a lack of available sensors from vendors capable of operating in the adverse environments of advanced aircraft.

Baumbick, Robert J.

1989-06-01

249

Technologies for Aircraft Noise Reduction  

NASA Technical Reports Server (NTRS)

Technologies for aircraft noise reduction have been developed by NASA over the past 15 years through the Advanced Subsonic Technology (AST) Noise Reduction Program and the Quiet Aircraft Technology (QAT) project. This presentation summarizes highlights from these programs and anticipated noise reduction benefits for communities surrounding airports. Historical progress in noise reduction and technologies available for future aircraft/engine development are identified. Technologies address aircraft/engine components including fans, exhaust nozzles, landing gear, and flap systems. New "chevron" nozzles have been developed and implemented on several aircraft in production today that provide significant jet noise reduction. New engines using Ultra-High Bypass (UHB) ratios are projected to provide about 10 EPNdB (Effective Perceived Noise Level in decibels) engine noise reduction relative to the average fleet that was flying in 1997. Audio files are embedded in the presentation that estimate the sound levels for a 35,000 pound thrust engine for takeoff and approach power conditions. The predictions are based on actual model scale data that was obtained by NASA. Finally, conceptual pictures are shown that look toward future aircraft/propulsion systems that might be used to obtain further noise reduction.

Huff, Dennis L.

2006-01-01

250

Parabolic aircraft solidification experiments  

NASA Technical Reports Server (NTRS)

A number of solidification experiments have been utilized throughout the Materials Processing in Space Program to provide an experimental environment which minimizes variables in solidification experiments. Two techniques of interest are directional solidification and isothermal casting. Because of the wide-spread use of these experimental techniques in space-based research, several MSAD experiments have been manifested for space flight. In addition to the microstructural analysis for interpretation of the experimental results from previous work with parabolic flights, it has become apparent that a better understanding of the phenomena occurring during solidification can be better understood if direct visualization of the solidification interface were possible. Our university has performed in several experimental studies such as this in recent years. The most recent was in visualizing the effect of convective flow phenomena on the KC-135 and prior to that were several successive contracts to perform directional solidification and isothermal casting experiments on the KC-135. Included in this work was the modification and utilization of the Convective Flow Analyzer (CFA), the Aircraft Isothermal Casting Furnace (ICF), and the Three-Zone Directional Solidification Furnace. These studies have contributed heavily to the mission of the Microgravity Science and Applications' Materials Science Program.

Workman, Gary L. (Principal Investigator); Smith, Guy A.; OBrien, Susan

1996-01-01

251

Sun powered aircraft design  

NASA Technical Reports Server (NTRS)

Two piloted aircraft have been developed and flown powered solely by photovoltaic cells in a program sponsored by the DuPont Company. The 30.8-kg (68-lb), 21.6-m (71-ft) span, Gossamer Penguin was used as a solar test bed, making a 2.6-km (1.6-mile) flight in August 1980. The 88.1-kg (194-lb), 14.3-m (47-ft) span Solar Challenger was developed for long flights in normal turbulence. Stressed to +9 G, it utilizes Kevlar, Nomex honeycomb-graphite sandwich wall tubes, expanded polystyrene foam ribs, and Mylar skin. With a 54.9-kg (121-lb) airframe, 33.1-kg (73-lb) propulsion system, and a 45.4-kg (100-lb) pilot, it flies on 1400 watts. In summer, the projected maximum climb is 1.0 m/s (200 ft/min) at 9,150 m (30,000 ft). Sixty purely solar-powered flights were made during winter 1980-1981. Using thermals, 1,070 m (3,500 ft) was reached with 115-minute duration.

Maccready, P. B.; Lissaman, P. B. S.; Morgan, W. R.; Burke, J. D.

1981-01-01

252

75 FR 35329 - Notification and Reporting of Aircraft Accidents or Incidents and Overdue Aircraft, and...  

Federal Register 2010, 2011, 2012, 2013, 2014

...to fewer scenarios than the original language. List of Subjects in 49 CFR Part 830 Aircraft accidents, Aircraft incidents, Aviation safety, Overdue aircraft notification and reporting, Reporting and recordkeeping requirements. 0 For the...

2010-06-22

253

76 FR 76686 - Notification and Reporting of Aircraft Accidents or Incidents and Overdue Aircraft, and...  

Federal Register 2010, 2011, 2012, 2013, 2014

...advisories that the NTSB may seek to investigate. List of Subjects in 49 CFR Part 830 Aircraft accidents, Aircraft incidents, Aviation safety, Overdue aircraft notification and reporting, Reporting and recordkeeping requirements. For the...

2011-12-08

254

Improving Aircraft Sequencing and Separation at a Small Aircraft Transportation System Airport  

E-print Network

and procedures for approach and landing during instrument meteorological conditions, the NASA small aircraftImproving Aircraft Sequencing and Separation at a Small Aircraft Transportation System Airport Kyle transportation system program demonstrated higher traffic volume general aviation operations at noncontrolled

Valasek, John

255

Ball lightning risk to aircraft  

NASA Astrophysics Data System (ADS)

Lightning is a rare but regular phenomenon for air traffic. Aircraft are designed to withstand lightning strikes. Research on lightning and aircraft can be called detailed and effective. In the last 57 years, 18 reported lightning aviation disasters with a fatality figure of at least 714 persons occurred. For comparison, the last JACDEC ten-year average fatality figure was 857. The majority encountered lightning in the climb, descent, approach and/or landing phase. Ball lightning, a metastable, rare lightning type, is also seen from and even within aircraft, but former research only reported individual incidents and did not generate a more detailed picture to ascertain whether it constitutes a significant threat to passenger and aircraft safety. Lacking established incident report channels, observations were often only passed on as "air-travel lore". In an effort to change this unsatisfactory condition, the authors have collected a first international dataset of 38 documented ball lightning aircraft incidents from 1938 to 2001 involving 13 reports over Europe, 13 over USA/Canada, and 7 over Russia. 18 (47%) reported ball lightning outside the aircraft, 18 (47%) inside, 2 cases lacked data. 8 objects caused minor damage, 8 major damage (total: 42%), only one a crash. No damage was reported in 18 cases. 3 objects caused minor crew injury. In most cases, ball lightning lasted several seconds. 11 (29%) incidents ended with an explosion of the object. A cloud-aircraft lightning flash was seen in only 9 cases (24%) of the data set. From the detailed accounts of air personnel in the last 70 years, it is evident that ball lightning is rarely, but consistently observed in connection with aircraft and can also occur inside the airframe. Reports often came from multiple professional witnesses and in several cases, damages were investigated by civil or military authorities. Although ball lightning is no main air traffic risk, the authors suggest that incident and accident reporting is expanded and in particular damage cases are routinely assessed and published. Aircrews should know that most ball lightning-aircraft-events require thunderstorm conditions, but not necessarily a cloud-aircraft lightning flash. With nearly 50% of inside-airframe ball lightning cases, safety precautions for airline passengers should be discussed and operationalized to minimize further risk.

Doe, R.; Keul, A.

2009-04-01

256

Airborne Subscale Transport Aircraft Research Testbed: Aircraft Model Development  

NASA Technical Reports Server (NTRS)

The Airborne Subscale Transport Aircraft Research (AirSTAR) testbed being developed at NASA Langley Research Center is an experimental flight test capability for research experiments pertaining to dynamics modeling and control beyond the normal flight envelope. An integral part of that testbed is a 5.5% dynamically scaled, generic transport aircraft. This remotely piloted vehicle (RPV) is powered by twin turbine engines and includes a collection of sensors, actuators, navigation, and telemetry systems. The downlink for the plane includes over 70 data channels, plus video, at rates up to 250 Hz. Uplink commands for aircraft control include over 30 data channels. The dynamic scaling requirement, which includes dimensional, weight, inertial, actuator, and data rate scaling, presents distinctive challenges in both the mechanical and electrical design of the aircraft. Discussion of these requirements and their implications on the development of the aircraft along with risk mitigation strategies and training exercises are included here. Also described are the first training (non-research) flights of the airframe. Additional papers address the development of a mobile operations station and an emulation and integration laboratory.

Jordan, Thomas L.; Langford, William M.; Hill, Jeffrey S.

2005-01-01

257

Dynamic properties of aircraft tires  

NASA Technical Reports Server (NTRS)

A research program has investigated the use of the von Schlippe string-type tire model for predicting the dynamic behavior of aircraft tires. The transfer-function method was used for theory evaluation. A more flexible two-constant modification to the string theory tire model is presented. Experiments were conducted on four types of scale model aircraft tires. Two types were of conventional bias construction, one type was an isotropic toroid, and one type was of unbelted radial construction. The conventional string theory and model gave predictions that were in good agreement with experimental data for bias constructed tires. The two-constant modification to string theory provided better agreement between predictions and experiment for the unconventional tires. The results indicate that the string theory tire model using static and slow-rolling tire properties predicts dynamic aircraft tire properties that have the same trends as the measured dynamic properties and, in most cases, provides good quantitative agreement.

Clark, S. K.; Dodge, R. N.; Nybakken, G. H.

1974-01-01

258

Flight directors for STOl aircraft  

NASA Technical Reports Server (NTRS)

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

Rabin, U. H.

1983-01-01

259

NASA's aircraft icing technology program  

NASA Technical Reports Server (NTRS)

NASA' Aircraft Icing Technology program is aimed at developing innovative technologies for safe and efficient flight into forecasted icing. The program addresses the needs of all aircraft classes and supports both commercial and military applications. The program is guided by three key strategic objectives: (1) numerically simulate an aircraft's response to an in-flight icing encounter, (2) provide improved experimental icing simulation facilities and testing techniques, and (3) offer innovative approaches to ice protection. Our research focuses on topics that directly support stated industry needs, and we work closely with industry to assure a rapid and smooth transfer of technology. This paper presents selected results that illustrate progress towards the three strategic objectives, and it provides a comprehensive list of references on the NASA icing program.

Reinmann, John J.

1991-01-01

260

Aircraft Skin Restoration and Evaluation  

NASA Astrophysics Data System (ADS)

The recent development of the cold spray technology has made possible the deposition of low porosity and oxide-free coatings with good adhesion and with almost no change in the microstructure of the coated parts. This focuses on the use of low-pressure cold spray process to repair damaged Al-based aircraft skin, aiming at obtaining dense coatings with strong adhesion to the Al2024-T3 alloy. In order to prove the feasibility of using of the cold spray process as a repair process for aircraft skin, series of characterisation/tests including microstructures, microhardness, adhesion strength, three-point bending, surface finish, fatigue test, and corrosion resistance were performed. The obtained results revealed that the low-pressure cold spray process is a suitable for the repair of aircraft skin.

Yandouzi, M.; Gaydos, S.; Guo, D.; Ghelichi, R.; Jodoin, B.

2014-08-01

261

Aircraft Skin Restoration and Evaluation  

NASA Astrophysics Data System (ADS)

The recent development of the cold spray technology has made possible the deposition of low porosity and oxide-free coatings with good adhesion and with almost no change in the microstructure of the coated parts. This focuses on the use of low-pressure cold spray process to repair damaged Al-based aircraft skin, aiming at obtaining dense coatings with strong adhesion to the Al2024-T3 alloy. In order to prove the feasibility of using of the cold spray process as a repair process for aircraft skin, series of characterisation/tests including microstructures, microhardness, adhesion strength, three-point bending, surface finish, fatigue test, and corrosion resistance were performed. The obtained results revealed that the low-pressure cold spray process is a suitable for the repair of aircraft skin.

Yandouzi, M.; Gaydos, S.; Guo, D.; Ghelichi, R.; Jodoin, B.

2014-12-01

262

14 CFR 47.51 - Triennial aircraft registration report.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Triennial aircraft registration report. 47.51 Section 47.51...AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRCRAFT REGISTRATION Certificates of Aircraft...

2010-01-01

263

14 CFR 135.145 - Aircraft proving and validation tests.  

Code of Federal Regulations, 2011 CFR

...Space 3 2011-01-01 2011-01-01 false Aircraft proving and validation tests. 135.145 Section...OPERATIONS AND RULES GOVERNING PERSONS ON BOARD SUCH AIRCRAFT Aircraft and Equipment § 135.145 Aircraft proving...

2011-01-01

264

14 CFR 47.61 - Dealer's Aircraft Registration Certificates.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 2011-01-01 false Dealer's Aircraft Registration Certificates. 47.61 Section 47...AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRCRAFT REGISTRATION Dealers' Aircraft Registration...

2011-01-01

265

14 CFR 47.61 - Dealer's Aircraft Registration Certificates.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 2013-01-01 false Dealer's Aircraft Registration Certificates. 47.61 Section 47...AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRCRAFT REGISTRATION Dealers' Aircraft Registration...

2013-01-01

266

14 CFR 47.33 - Aircraft not previously registered anywhere.  

Code of Federal Regulations, 2011 CFR

...Space 1 2011-01-01 2011-01-01 false Aircraft not previously registered anywhere. 47.33 Section...AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRCRAFT REGISTRATION Certificates of Aircraft...

2011-01-01

267

14 CFR 47.33 - Aircraft not previously registered anywhere.  

Code of Federal Regulations, 2013 CFR

...Space 1 2013-01-01 2013-01-01 false Aircraft not previously registered anywhere. 47.33 Section...AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRCRAFT REGISTRATION Certificates of Aircraft...

2013-01-01

268

14 CFR 135.145 - Aircraft proving and validation tests.  

Code of Federal Regulations, 2014 CFR

...Space 3 2014-01-01 2014-01-01 false Aircraft proving and validation tests. 135.145 Section...OPERATIONS AND RULES GOVERNING PERSONS ON BOARD SUCH AIRCRAFT Aircraft and Equipment § 135.145 Aircraft proving...

2014-01-01

269

14 CFR 47.61 - Dealer's Aircraft Registration Certificates.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 2012-01-01 false Dealer's Aircraft Registration Certificates. 47.61 Section 47...AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRCRAFT REGISTRATION Dealers' Aircraft Registration...

2012-01-01

270

14 CFR 47.33 - Aircraft not previously registered anywhere.  

Code of Federal Regulations, 2014 CFR

...Space 1 2014-01-01 2014-01-01 false Aircraft not previously registered anywhere. 47.33 Section...AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRCRAFT REGISTRATION Certificates of Aircraft...

2014-01-01

271

14 CFR 135.145 - Aircraft proving and validation tests.  

Code of Federal Regulations, 2013 CFR

...Space 3 2013-01-01 2013-01-01 false Aircraft proving and validation tests. 135.145 Section...OPERATIONS AND RULES GOVERNING PERSONS ON BOARD SUCH AIRCRAFT Aircraft and Equipment § 135.145 Aircraft proving...

2013-01-01

272

14 CFR 47.61 - Dealer's Aircraft Registration Certificates.  

Code of Federal Regulations, 2014 CFR

...2014-01-01 2014-01-01 false Dealer's Aircraft Registration Certificates. 47.61 Section 47...AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRCRAFT REGISTRATION Dealers' Aircraft Registration...

2014-01-01

273

14 CFR 47.33 - Aircraft not previously registered anywhere.  

Code of Federal Regulations, 2012 CFR

...Space 1 2012-01-01 2012-01-01 false Aircraft not previously registered anywhere. 47.33 Section...AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRCRAFT REGISTRATION Certificates of Aircraft...

2012-01-01

274

14 CFR 135.145 - Aircraft proving and validation tests.  

Code of Federal Regulations, 2012 CFR

...Space 3 2012-01-01 2012-01-01 false Aircraft proving and validation tests. 135.145 Section...OPERATIONS AND RULES GOVERNING PERSONS ON BOARD SUCH AIRCRAFT Aircraft and Equipment § 135.145 Aircraft proving...

2012-01-01

275

NASA's aircraft icing analysis program  

NASA Technical Reports Server (NTRS)

An overview of the NASA ongoing efforts to develop an aircraft icing analysis capability is presented. Discussions are included of the overall and long term objectives of the program as well as current capabilities and limitations of the various computer codes being developed. Descriptions are given of codes being developed to analyze two- and three-dimensional trajectories of water droplets, airfoil ice accretion, aerodynamic performance degradation of components and complete aircraft configurations, electrothermal deicer, fluid freezing point depressant antideicer and electro-impulse deicer. The need for bench mark and verification data to support the code development is also discussed, and selected results of experimental programs are presented.

Shaw, R. J.

1986-01-01

276

Aircraft anti-insect system  

NASA Technical Reports Server (NTRS)

Insect debris is removed from or prevented from adhering to insect impingement areas of an aircraft, particularly on an inlet cowl of an engine, by heating the area to 180.degree.-500.degree. C. An apparatus comprising a means to bring hot air from the aircraft engine to a plenum contiguous to the insect impingement area provides for the heating of the insect impingement areas to the required temperatures. The plenum can include at least one tube with a plurality of holes contained in a cavity within the inlet cowl. It can also include an envelope with a plurality of holes on its surface contained in a cavity within the inlet cowl.

Spiro, Clifford Lawrence (Inventor); Fric, Thomas Frank (Inventor); Leon, Ross Michael (Inventor)

1997-01-01

277

Aircraft gas turbine emissions challenge  

SciTech Connect

The new generation of jet powered aircraft faces a significant challenge to reduce pollutant emissions while increasing fuel efficiency. Carbon monoxide (CO) and unburned hydrocarbon (HC) emissions are already very low and continued control of these pollutants is expected as engine temperatures and pressure ratios are increased. In contrast, significant system design improvements are needed to reduce oxides of nitrogen (NO[sub x]) emissions because of their harmful effect on the earth's ozone layer. This paper discusses the prospects and technical approaches for significant NO[sub x] reductions in current and future subsonic and supersonic aircraft.

Koff, B.L. (Pratt and Whitney, West Palm Beach, FL (United States))

1994-07-01

278

Model of aircraft noise adaptation  

NASA Technical Reports Server (NTRS)

Development of an aircraft noise adaptation model, which would account for much of the variability in the responses of subjects participating in human response to noise experiments, was studied. A description of the model development is presented. The principal concept of the model, was the determination of an aircraft adaptation level which represents an annoyance calibration for each individual. Results showed a direct correlation between noise level of the stimuli and annoyance reactions. Attitude-personality variables were found to account for varying annoyance judgements.

Dempsey, T. K.; Coates, G. D.; Cawthorn, J. M.

1977-01-01

279

Aircraft Dynamic Modeling in Turbulence  

NASA Technical Reports Server (NTRS)

A method for accurately identifying aircraft dynamic models in turbulence was developed and demonstrated. The method uses orthogonal optimized multisine excitation inputs and an analytic method for enhancing signal-to-noise ratio for dynamic modeling in turbulence. A turbulence metric was developed to accurately characterize the turbulence level using flight measurements. The modeling technique was demonstrated in simulation, then applied to a subscale twin-engine jet transport aircraft in flight. Comparisons of modeling results obtained in turbulent air to results obtained in smooth air were used to demonstrate the effectiveness of the approach.

Morelli, Eugene A.; Cunninham, Kevin

2012-01-01

280

Aircraft accidents : method of analysis  

NASA Technical Reports Server (NTRS)

The revised report includes the chart for the analysis of aircraft accidents, combining consideration of the immediate causes, underlying causes, and results of accidents, as prepared by the special committee, with a number of the definitions clarified. A brief statement of the organization and work of the special committee and of the Committee on Aircraft Accidents; and statistical tables giving a comparison of the types of accidents and causes of accidents in the military services on the one hand and in civil aviation on the other, together with explanations of some of the important differences noted in these tables.

1931-01-01

281

Minimum noise impact aircraft trajectories  

NASA Technical Reports Server (NTRS)

Numerical optimization is used to compute the optimum flight paths, based upon a parametric form that implicitly includes some of the problem restrictions. The other constraints are formulated as penalties in the cost function. Various aircraft on multiple trajectores (landing and takeoff) can be considered. The modular design employed allows for the substitution of alternate models of the population distribution, aircraft noise, flight paths, and annoyance, or for the addition of other features (e.g., fuel consumption) in the cost function. A reduction in the required amount of searching over local minima was achieved through use of the presence of statistical lateral dispersion in the flight paths.

Jacobson, I. D.; Melton, R. G.

1981-01-01

282

Alternative general-aircraft engines  

NASA Technical Reports Server (NTRS)

The most promising alternative engine (or engines) for application to general aircraft in the post-1985 time period was defined, and the level of technology was cited to the point where confident development of a new engine can begin early in the 1980's. Low emissions, multifuel capability, and fuel economy were emphasized. Six alternative propulsion concepts were considered to be viable candidates for future general-aircraft application: the advanced spark-ignition piston, rotary combustion, two- and four-stroke diesel, Stirling, and gas turbine engines.

Tomazic, W. A.

1976-01-01

283

NASA's Aircraft Icing Analysis Program  

NASA Technical Reports Server (NTRS)

An overview of the NASA ongoing efforts to develop an aircraft icing analysis capability is presented. Discussions are included of the overall and long term objectives of the program as well as current capabilities and limitations of the various computer codes being developed. Descriptions are given of codes being developed to analyze two and three dimensional trajectories of water droplets, airfoil ice accretion, aerodynamic performance degradation of components and complete aircraft configurations, electrothermal deicer, fluid freezing point depressant antideicer and electro-impulse deicer. The need for bench mark and verification data to support the code development is also discussed, and selected results of experimental programs are presented.

Shaw, R. J.

1986-01-01

284

14 CFR 135.25 - Aircraft requirements.  

Code of Federal Regulations, 2014 CFR

...holder files a copy of the aircraft lease or charter agreement with the FAA Aircraft Registry, Department of Transportation, 6400 South MacArthur Boulevard, Oklahoma City, OK (Mailing address: P.O. Box 25504, Oklahoma City, OK 73125)....

2014-01-01

285

14 CFR 135.25 - Aircraft requirements.  

Code of Federal Regulations, 2013 CFR

...holder files a copy of the aircraft lease or charter agreement with the FAA Aircraft Registry, Department of Transportation, 6400 South MacArthur Boulevard, Oklahoma City, OK (Mailing address: P.O. Box 25504, Oklahoma City, OK 73125)....

2013-01-01

286

14 CFR 135.25 - Aircraft requirements.  

Code of Federal Regulations, 2012 CFR

...holder files a copy of the aircraft lease or charter agreement with the FAA Aircraft Registry, Department of Transportation, 6400 South MacArthur Boulevard, Oklahoma City, OK (Mailing address: P.O. Box 25504, Oklahoma City, OK 73125)....

2012-01-01

287

14 CFR 135.25 - Aircraft requirements.  

Code of Federal Regulations, 2011 CFR

...holder files a copy of the aircraft lease or charter agreement with the FAA Aircraft Registry, Department of Transportation, 6400 South MacArthur Boulevard, Oklahoma City, OK (Mailing address: P.O. Box 25504, Oklahoma City, OK 73125)....

2011-01-01

288

14 CFR 135.25 - Aircraft requirements.  

Code of Federal Regulations, 2010 CFR

...holder files a copy of the aircraft lease or charter agreement with the FAA Aircraft Registry, Department of Transportation, 6400 South MacArthur Boulevard, Oklahoma City, OK (Mailing address: P.O. Box 25504, Oklahoma City, OK 73125)....

2010-01-01

289

Aircraft Electronics Maintenance Training Simulator. Curriculum Outlines.  

ERIC Educational Resources Information Center

Instructional materials are provided for nine courses in an aircraft electronics maintenance training program. Courses are as follows: aviation basic electricity, direct current and alternating current electronics, basic avionic installations, analog electronics, digital electronics, microcomputer electronics, radio communications, aircraft

Blackhawk Technical Coll., Janesville, WI.

290

Propulsion system concepts for silent aircraft  

E-print Network

The noise emitted by commercial aircraft is a major inhibitor of the growth of commercial air transport and is a critical environmental issue in air transportation. A functionally-silent aircraft is envisioned to achieve ...

Manneville, Alexis, 1978-

2004-01-01

291

Maintenance cost studies of present aircraft subsystems  

E-print Network

This report describes two detailed studies of actual maintenance costs for present transport aircraft. The first part describes maintenance costs for jet transport aircraft broken down into subsystem costs according to an ...

Pearlman, Chaim Herman Shalom

1966-01-01

292

Optimal scheduling of fighter aircraft maintenance  

E-print Network

The effective scheduling of fighter aircraft maintenance in the Air Force is crucial to overall mission accomplishment. An effective maintenance scheduling policy maximizes the use of maintenance resources and aircraft ...

Cho, Philip Y

2011-01-01

293

Fuel Cell Council Working Group on Aircraft and Aircraft Ground Support Fuel  

E-print Network

Fuel Cell Council Working Group on Aircraft and Aircraft Ground Support Fuel Cell Applications #12;Topics · The US Fuel Cell Council Aircraft and Aircraft Support Working Group Establishment Working Group, nonprofits, government Advocacy Regulations Safety and standardization Education Strategic Alliances #12;Our

294

Method and apparatus for monitoring aircraft components  

DOEpatents

Operability of aircraft mechanical components is monitored by analyzing the voltage output of an electrical generator of the aircraft. Alternative generators, for a turbine-driven rotor aircraft, include the gas producer turbine tachometer generator, the power turbine tachometer generator, and the aircraft systems power producing starter/generator. Changes in the peak amplitudes of the fundamental frequency and its harmonics are correlated to changes in condition of the mechanical components.

Dickens, Larry M. (Oak Ridge, TN); Haynes, Howard D. (Knoxville, TN); Ayers, Curtis W. (Clinton, TN)

1996-01-01

295

Investigation of aircraft generated VLF interference  

Microsoft Academic Search

Reception distances of VLF\\/LF transmissions, on board the KC-135 aircraft, have been severely restricted by electromagnetic interference generated by the aircraft's equipment. This interference has prevented the accurate measurement of propagation data at distances greater than 1,000 miles when using the aircraft's omnidirectional antenna. With the use of a directional loop antenna mounted on the aircraft's boom, reception distances of

W. Bonser; A. J. Mlinar

1977-01-01

296

The NASA Aircraft Energy Efficiency program  

NASA Technical Reports Server (NTRS)

A review is provided of the goals, objectives, and recent progress in each of six aircraft energy efficiency programs aimed at improved propulsive, aerodynamic and structural efficiency for future transport aircraft. Attention is given to engine component improvement, an energy efficient turbofan engine, advanced turboprops, revolutionary gains in aerodynamic efficiency for aircraft of the late 1990s, laminar flow control, and composite primary aircraft structures.

Klineberg, J. M.

1979-01-01

297

Method and apparatus for monitoring aircraft components  

DOEpatents

Operability of aircraft mechanical components is monitored by analyzing the voltage output of an electrical generator of the aircraft. Alternative generators, for a turbine-driven rotor aircraft, include the gas producer turbine tachometer generator, the power turbine tachometer generator, and the aircraft systems power producing starter/generator. Changes in the peak amplitudes of the fundamental frequency and its harmonics are correlated to changes in condition of the mechanical components. 14 figs.

Dickens, L.M.; Haynes, H.D.; Ayers, C.W.

1996-01-16

298

40 CFR 87.6 - Aircraft safety.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 2012-07-01 false Aircraft safety. 87.6 Section 87.6... Definitions. § 87.6 Aircraft safety. Link to an amendment published...forth as follows: § 87.6 Aircraft safety. The provisions of...

2012-07-01

299

40 CFR 87.6 - Aircraft safety.  

Code of Federal Regulations, 2014 CFR

...2014-07-01 2013-07-01 true Aircraft safety. 87.6 Section 87.6...General Provisions § 87.6 Aircraft safety. The provisions of this...without creating a hazard to aircraft safety. [77 FR 36381, June...

2014-07-01

300

40 CFR 87.6 - Aircraft safety.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Aircraft safety. 87.6 Section 87.6...General Provisions § 87.6 Aircraft safety. The provisions of this...without creating a hazard to aircraft safety. [77 FR 36381, June...

2013-07-01

301

Contribution of laser anemometry to aircraft safety  

Microsoft Academic Search

The contribution of laser anemometry to aircraft safety through its use in the calibration of aircraft wind and pressure measurements and in wind shear detection is considered. Following a discussion of the principles of laser anemometry and four standard pressure error calibration methods, the application of laser anemometry to the calibration of aircraft incidence and sideslip is discussed. Calibration precisions

Jacques Mandle

1987-01-01

302

A Ubiquitous Computing Environment for Aircraft Maintenance  

E-print Network

in the area of aircraft maintenance. Extensive requirements regarding quality, safety, and documentationA Ubiquitous Computing Environment for Aircraft Maintenance Matthias Lampe Department of Computer as well as high costs for having aircrafts idle during maintenance demand for an efficient execution

303

COMBAT AIRCRAFT AGILITY METRICS - A REVIEW  

Microsoft Academic Search

With changing combat environments, traditional measures of merit for fighter aircraft per- formance have largely proved insufficient to analyze combat capability. Combat experience has shown that the upper hand lies with an aircraft that has superior maneuverability across a large part of the flight regime. Agility metrics have come to provide a tool that would be capable of evaluating aircraft

Aditya A. Paranjape; N. Ananthkrishnan

304

Aircraft wake turbulence minimization by aerodynamic means  

NASA Technical Reports Server (NTRS)

The paper reviews NASA's efforts on wake vortex turbulence minimization by aerodynamic design or retrofit modifications to large transport aircraft. Theoretical and experimental (ground-based and flight) results are presented which show that the adverse effects of a vortex wake produced by a large aircraft on a small following aircraft can be reduced significantly.

Gessow, A.

1974-01-01

305

Strategic Planning in Fractional Aircraft Ownership Programs  

E-print Network

and profitability. Key words: Aircraft routing, crew scheduling, column generation, set partitioning, decisionStrategic Planning in Fractional Aircraft Ownership Programs Yufeng Yaoa* , Ã?zlem Erguna , Ellis, the partial owner of an aircraft is entitled to certain flight hours per year, and the management company

Ergun, Ozlem

306

Aircraft Power Generators: Hybrid Modeling and  

E-print Network

Aircraft Power Generators: Hybrid Modeling and Simulation for Fault Detection ASHRAF TANTAWY. INTRODUCTION The Integrated drive generator (IDG) is the primary source for electrical power in the aircraft. The system draws its power from the main aircraft engines and comprises two synchronous generators

Koutsoukos, Xenofon D.

307

Lightweight diesel aircraft engines for general aviation  

Microsoft Academic Search

This project reintroduces the diesel engine as an aircraft powerplant. A concept design study of two engines was conducted to define configurations and applicable advanced technologies. The information generated in the course of this study was then used to evaluate the performance of two aircraft: a six-place twin and a four-place single. The computer generated aircraft performance data show a

Brouwers

1980-01-01

308

Arnold Schwarzenegger AIRCRAFT MEASUREMENTS OF THE  

E-print Network

Arnold Schwarzenegger Governor AIRCRAFT MEASUREMENTS OF THE IMPACTS OF POLLUTION AEROSOLS ON CLOUDS Documentation of the SUPRECIP2 Program Appendix C. The SOAR Research Aircraft During SUPRECIP2 Appendix D Data for Flights of the Cloud Physics and Aerosol Aircraft #12; #12;APA-1 Appendix A Worldwide

309

7, 25312560, 2007 Aircraft pollution: a  

E-print Network

ACPD 7, 2531­2560, 2007 Aircraft pollution: a futuristic view O. A. Søvde et al. Title Page Chemistry and Physics Discussions Aircraft pollution: a futuristic view O. A. Søvde 1 , M. Gauss 1 , I. S. A Correspondence to: O. A. Søvde (asovde@geo.uio.no) 2531 #12;ACPD 7, 2531­2560, 2007 Aircraft pollution

Paris-Sud XI, Université de

310

SCIENTIFIC OPPORTUNITIES LONG-RANGE AIRCRAFT  

E-print Network

LARA SCIENTIFIC OPPORTUNITIES FOR A LONG-RANGE AIRCRAFT FOR RESEARCH IN ANTARCTICA SCIENTIFIC OPPORTUNITIES FOR A LONG-RANGE AIRCRAFT FOR RESEARCH IN ANTARCTICA LARA #12;ACKNOWLEDGMENTS The workshop SEPTEMBER 27-29, 2004 LARA SCIENTIFIC OPPORTUNITIES FOR A LONG-RANGE AIRCRAFT FOR RESEARCH IN ANTARCTICA

Howat, Ian M.

311

Aircraft System Identification Using Artificial Neural Networks  

E-print Network

Aircraft System Identification Using Artificial Neural Networks Kenton Kirkpatrick , Jim May Jr linear system identification for aircraft using artificial neural net- works. The output of a linear aircraft system consists of linear combinations of state and control inputs. Determining linear models

Valasek, John

312

20 Highlights Profiling the atmosphere with aircraft  

E-print Network

20 Highlights Profiling the atmosphere with aircraft Jitze van der Meulen Introduction Weather aircrafts perform continuous observations during their flights and especially during ascent and descent of aircraft, quality monitoring services and rapid feed back to the AMDAR operations system are essential

Haak, Hein

313

Cooperative Electronic Chaining Using Small Unmanned Aircraft  

E-print Network

Cooperative Electronic Chaining Using Small Unmanned Aircraft Cory R. Dixon and Eric W. Frew RECUV, University of Colorado, Boulder, CO, 80309, USA When using a team of small unmanned aircraft-of-sight communication constraints between an individual aircraft and a ground station, and not the endurance range

Frew, Eric W.

314

2, 20452074, 2002 Emission by aircraft  

E-print Network

ACPD 2, 2045­2074, 2002 Emission by aircraft engines A. Sorokin et al. Title Page Abstract soot particles by aircraft engines A. Sorokin1 , X. Vancassel2 , and P. Mirabel2 1 Central Institute@illite.u-strasbg.fr) 2045 #12;ACPD 2, 2045­2074, 2002 Emission by aircraft engines A. Sorokin et al. Title Page Abstract

Paris-Sud XI, Université de

315

The Aircraft Dispatcher "One stop shopping"  

E-print Network

The Aircraft Dispatcher "One stop shopping" source of information for the pilot #12;What there for not more than one hour, no person may start a flight unless an aircraft dispatcher specifically authorizes aircraft. They operate approximately 20,000 flights per day. They employ almost 50,000 pilots

316

Subsonic Aircraft Safety Icing Study  

NASA Technical Reports Server (NTRS)

NASA's Integrated Resilient Aircraft Control (IRAC) Project is one of four projects within the agency s Aviation Safety Program (AvSafe) in the Aeronautics Research Mission Directorate (ARMD). The IRAC Project, which was redesigned in the first half of 2007, conducts research to advance the state of the art in aircraft control design tools and techniques. A "Key Decision Point" was established for fiscal year 2007 with the following expected outcomes: document the most currently available statistical/prognostic data associated with icing for subsonic transport, summarize reports by subject matter experts in icing research on current knowledge of icing effects on control parameters and establish future requirements for icing research for subsonic transports including the appropriate alignment. This study contains: (1) statistical analyses of accident and incident data conducted by NASA researchers for this "Key Decision Point", (2) an examination of icing in other recent statistically based studies, (3) a summary of aviation safety priority lists that have been developed by various subject-matter experts, including the significance of aircraft icing research in these lists and (4) suggested future requirements for NASA icing research. The review of several studies by subject-matter experts was summarized into four high-priority icing research areas. Based on the Integrated Resilient Aircraft Control (IRAC) Project goals and objectives, the IRAC project was encouraged to conduct work in all of the high-priority icing research areas that were identified, with the exception of the developing of methods to sense and document actual icing conditions.

Jones, Sharon Monica; Reveley, Mary S.; Evans, Joni K.; Barrientos, Francesca A.

2008-01-01

317

Simplified navigation for unmanned aircraft  

Microsoft Academic Search

This paper describes some design considerations of a navigation filter for an unmanned aircraft. Emphasis is on a simple, but accurate approach to navigation. Design considerations are discussed for the implementation of a fixed gain extended Kalman filter. Representative sensors including true airspeed, doppler, and LORAN are described, and their integration into a modular navigation system is explained.

R. W. Elsner; M. G. Currie

1973-01-01

318

Morphing wings for unmanned aircraft  

Microsoft Academic Search

Here a computational model is presented which predicts the force, stroke and energy needed to overcome aerodynamic loads encountered by morphing wings, to perform aircraft manoeuvres. The aerodynamic load algorithms have been verified against more time-expensive codes. The overall model allows for desired flight-path inputs and variable control algorithms. The four modules that make up the model integrate well, to

Greg W. Pettit; Harry H. Robertshaw; Dan J. Inman

2001-01-01

319

Inflight characterization of aircraft icing  

NASA Astrophysics Data System (ADS)

This thesis advances the development of the Ice Management System (IMS), which has been previously proposed as an additional layer of safety against aircraft icing accidents, by presenting and validating a conceptual design for the icing characterization function of the IMS. This icing characterization function seeks to provide a near real-time estimate of the degradation of the aircraft flight dynamics due to icing. The icing characterization is extracted from various information sources comprising Hinfinity parameter identification of the flight dynamics, steady-state characterization of the aircraft trim, aerodynamic hinge moment sensing, and an estimate of the flight-dynamics excitation. Two aspects of the icing characterization are novel: (i) real-time Hinfinity parameter identification of the flight dynamics, and (ii) preprocessing and assimilation of the various measurements that individually provide partial information on the icing degradation into a single comprehensive icing characterization, the so-called sensor fusion function. These two aspects of the icing characterization are validated by applying them in computer simulation to a rich set of flight scenarios. Moreover, the Hinfinity parameter identification is applied successfully to flight-test data generated by the NASA Twin Otter icing research aircraft, and validated against an existing flight-dynamics identification technique. Finally, consideration of an independent icing degradation estimate from atmospheric and photographic measurements demonstrates that the H infinity parameter estimate provides an indication of icing degradation for a natural-icing flight test.

Melody, James William

320

Aircraft Lightning Electromagnetic Environment Measurement  

NASA Technical Reports Server (NTRS)

This paper outlines a NASA project plan for demonstrating a prototype lightning strike measurement system that is suitable for installation onto research aircraft that already operate in thunderstorms. This work builds upon past data from the NASA F106, FAA CV-580, and Transall C-180 flight projects, SAE ARP5412, and the European ILDAS Program. The primary focus is to capture airframe current waveforms during attachment, but may also consider pre and post-attachment current, electric field, and radiated field phenomena. New sensor technologies are being developed for this system, including a fiber-optic Faraday polarization sensor that measures lightning current waveforms from DC to over several Megahertz, and has dynamic range covering hundreds-of-volts to tens-of-thousands-of-volts. A study of the electromagnetic emission spectrum of lightning (including radio wave, microwave, optical, X-Rays and Gamma-Rays), and a compilation of aircraft transfer-function data (including composite aircraft) are included, to aid in the development of other new lightning environment sensors, their placement on-board research aircraft, and triggering of the onboard instrumentation system. The instrumentation system will leverage recent advances in high-speed, high dynamic range, deep memory data acquisition equipment, and fiber-optic interconnect.

Ely, Jay J.; Nguyen, Truong X.; Szatkowski, George N.

2011-01-01

321

Carbon fiber counting. [aircraft structures  

NASA Technical Reports Server (NTRS)

A method was developed for characterizing the number and lengths of carbon fibers accidentally released by the burning of composite portions of civil aircraft structure in a jet fuel fire after an accident. Representative samplings of carbon fibers collected on transparent sticky film were counted from photographic enlargements with a computer aided technique which also provided fiber lengths.

Pride, R. A.

1980-01-01

322

Promising Electric Aircraft Drive Systems  

NASA Technical Reports Server (NTRS)

An overview of electric aircraft propulsion technology performance thresholds for key power system components is presented. A weight comparison of electric drive systems with equivalent total delivered energy is made to help identify component performance requirements, and promising research and development opportunities.

Dudley, Michael R.

2010-01-01

323

Disturbance caused by aircraft noise  

NASA Technical Reports Server (NTRS)

Noise pollution caused by the presence of airfields adjacent to residential areas is studied. Noise effects on the sleep of residents near airports and the degree of the residents noise tolerance are evaluated. What aircraft noises are annoying and to what extent the annoyance varies with sound level are discussed.

Josse, R.

1980-01-01

324

Hornet maintenance [aircraft system management  

Microsoft Academic Search

A step toward life cycle cost reduction was the introduction of a Flight Incident Recording and Aircraft Monitoring Set (FIRAMS) in the F\\/A-18 Hornet. FIRAMS provides onboard nonvolatile storage of operational flight information and maintenance parameters. It also integrates fuel and engine displays and performs the fuel gaging and transfer functions. FIRAMS also promotes the concept of using onboard computers

H. A. Chase

1989-01-01

325

System design and aircraft integration  

NASA Astrophysics Data System (ADS)

The Integrated Helmet Audio/Visual System (IHAVS) suite is composed of the GEC Helmet Mounted Display (HMD), Armstrong Labs 3-D Audio system, Polhemus Head Tracker (HT) and SMiths Interactive Voice Module (IVM). The LORAL NITE Hawk Targeting Self Cooled IR pod (TFLIR) was added, supplementing the IHAVS for off-boresight target management. The lightweight HMD generates a high resolution visor projected display. Symbology displayed within the binocular and fully overlapped 40 degree field of view presents aircraft moding, navigation, weapon delivery, and threat data to the pilot. The 3-D Audio system generates four audio cues localized to within 10 degrees of the commanded position. THe specialized headset localizes TFLIR position and threat audio cues. The HT system provides helmet position to the aircraft, the HMD and 3-D Audio system. Twelve IVM digital voice output reports aircraft status. The T/AV-8B aircraft and avionics architecture are discussed laying the foundation for the described integration of the IHAVS suite. Integrated together, these systems provide the pilot with greatly increased field of regard for target recognition, designation and attack. Tightly coupled to the IHAVS suite, the TFLIR allows off-boresight target management and the field of regard is well matched and complements the IHAVS.

Flint, John R.

1996-06-01

326

Aircraft Identification by Moment Invariants  

Microsoft Academic Search

Although many systems for optical reading of printed matter have been developed and are now in wide use, comparatively little success has been achieved in the automatic interpretation of optical images of three-dimensional scenes. This paper is addressed to the latter problem and is specifically concerned with automatic recognition of aircraft types from optical images. An experimental system is described

Sahibsingh A. Dudani; Kenneth J. Breeding; Robert B. Mcghee

1977-01-01

327

Aircraft Cabin Environmental Quality Sensors  

E-print Network

and airlines typically accept the likelihood of requirements for sensors and urge simplicity and low cost.Airlines a Crew Sensor-Related Issues Compliance with FARS and ASHRAE Standard Safety, low cost,low (L) priorities. Aircraft manufacturers: cost, design Passengers: comfort and protection Airlines:

Gundel, Lara

2010-01-01

328

Survival analysis of aging aircraft  

NASA Astrophysics Data System (ADS)

This study pushes systems engineering of aging aircraft beyond the boundaries of empirical and deterministic modeling by making a sharp break with the traditional laboratory-derived corrosion prediction algorithms that have shrouded real-world failures of aircraft structure. At the heart of this problem is the aeronautical industry's inability to be forthcoming in an accurate model that predicts corrosion failures in aircraft in spite of advances in corrosion algorithms or improvements in simulation and modeling. The struggle to develop accurate corrosion probabilistic models stems from a multitude of real-world interacting variables that synergistically influence corrosion in convoluted and complex ways. This dissertation, in essence, offers a statistical framework for the analysis of structural airframe corrosion failure by utilizing real-world data while considering the effects of interacting corrosion variables. This study injects realism into corrosion failures of aging aircraft systems by accomplishing four major goals related to the conceptual and methodological framework of corrosion modeling. First, this work connects corrosion modeling from the traditional, laboratory derived algorithms to corrosion failures in actual operating aircraft. This work augments physics-based modeling by examining the many confounding and interacting variables, such as environmental, geographical and operational, that impact failure of airframe structure. Examined through the lens of censored failure data from aircraft flying in a maritime environment, this study enhances the understanding between the triad of the theoretical, laboratory and real-world corrosion. Secondly, this study explores the importation and successful application of an advanced biomedical statistical tool---survival analysis---to model censored corrosion failure data. This well-grounded statistical methodology is inverted from a methodology that analyzes survival to one that examines failures. Third, this work demonstrates the development of a probabilistic corrosion failure model using survival analysis methods and techniques. Using a parsimonious approach, the coefficients of a Cox proportional hazards model were derived from a set of environmental, geographical and operational predictor variables. To determine if the variables satisfied the proportional hazard assumption, numerous statistical tests were performed---such as the equivalence tests of the log rank, Wilcoxon, Peto-Peto and Fleming-Harrington---and graphical plots generated such as observed-versus-expected plots and log(-log) survival curves. Finally, in a paradigm enhancement to current design methodologies, this dissertation place sets survival analysis modeling in the context of an emerging holistic structural integrity philosophy. While traditional aircraft design and life prediction methodologies consider only the cyclic fatigue domain without consideration to the environmental or unique operating spectrum that aircraft may fly in, a holistic approach considers the cradle-to-grave driving forces in the life of a component, such as corrosion assisted crack nucleation in a material. This dissertation, which uses real-world failure data obtained from structural aircraft components, is poised to narrow the cradle-to-grave loop and provide holistic feedback in the understanding of aircraft structural system failures.

Benavides, Samuel

329

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

330

Perspectives on Highly Adaptive or Morphing Aircraft  

NASA Technical Reports Server (NTRS)

The ability to adapt to different flight conditions has been fundamental to aircraft design since the Wright Brothers first flight. Over a hundred years later, unconventional aircraft adaptability, often called aircraft morphing has become a topic of considerable renewed interest. In the past two decades, this interest has been largely fuelled by advancements in multi-functional or smart materials and structures. However, highly adaptive or morphing aircraft is certainly a cross-discipline challenge that stimulates a wide range of design possibilities. This paper will review some of the history of morphing aircraft including recent research programs and discuss some perspectives on this work.

McGowan, Anna-Maria R.; Vicroy, Dan D.; Busan, Ronald C.; Hahn, Andrew S.

2009-01-01

331

Hydrogen Storage for Aircraft Applications Overview  

NASA Technical Reports Server (NTRS)

Advances in fuel cell technology have brought about their consideration as sources of power for aircraft. This power can be utilized to run aircraft systems or even provide propulsion power. One of the key obstacles to utilizing fuel cells on aircraft is the storage of hydrogen. An overview of the potential methods of hydrogen storage was compiled. This overview identifies various methods of hydrogen storage and points out their advantages and disadvantages relative to aircraft applications. Minimizing weight and volume are the key aspects to storing hydrogen within an aircraft. An analysis was performed to show how changes in certain parameters of a given storage system affect its mass and volume.

Colozza, Anthony J.; Kohout, Lisa (Technical Monitor)

2002-01-01

332

Factors influencing aircraft ground handling performance  

NASA Technical Reports Server (NTRS)

Problems associated with aircraft ground handling operations on wet runways are discussed and major factors which influence tire/runway braking and cornering traction capability are identified including runway characteristics, tire hydroplaning, brake system anomalies, and pilot inputs. Research results from tests with instrumented ground vehicles and aircraft, and aircraft wet runway accident investigation are summarized to indicate the effects of different aircraft, tire, and runway parameters. Several promising means are described for improving tire/runway water drainage capability, brake system efficiency, and pilot training to help optimize aircraft traction performance on wet runways.

Yager, T. J.

1983-01-01

333

Refurbishment of NASA aircraft with fire-retardant materials. [aircraft compartments of commercial aircraft  

NASA Technical Reports Server (NTRS)

Selected fire-retardant materials for possible application to commercial aircraft are described. The results of flammability screening tests and information on the physical and chemical properties of both original and newly installed materials after extended use are presented in tabular form, with emphasis on wear properties, strength, puncture and tear resistances, and cleanability.

Supkis, D. E.

1975-01-01

334

Stability-Augmentation Devices for Miniature Aircraft  

NASA Technical Reports Server (NTRS)

Non-aerodynamic mechanical devices are under consideration as means to augment the stability of miniature autonomous and remotely controlled aircraft. Such aircraft can be used for diverse purposes, including military reconnaissance, radio communications, and safety-related monitoring of wide areas. The need for stability-augmentation devices arises because adverse meteorological conditions generally affect smaller aircraft more strongly than they affect larger aircraft: Miniature aircraft often become uncontrollable under conditions that would not be considered severe enough to warrant grounding of larger aircraft. The need for the stability-augmentation devices to be non-aerodynamic arises because there is no known way to create controlled aerodynamic forces sufficient to counteract the uncontrollable meteorological forces on miniature aircraft. A stability-augmentation device of the type under consideration includes a mass pod (a counterweight) at the outer end of a telescoping shaft, plus associated equipment to support the operation of the aircraft. The telescoping shaft and mass pod are stowed in the rear of the aircraft. When deployed, they extend below the aircraft. Optionally, an antenna for radio communication can be integrated into the shaft. At the time of writing this article, the deployment of the telescoping shaft and mass pod was characterized as passive and automatic, but information about the deployment mechanism(s) was not available. The feasibility of this stability-augmentation concept was demonstrated in flights of hand-launched prototype aircraft.

Wood, RIchard M.

2005-01-01

335

Instrument for Aircraft-Icing and Cloud-Physics Measurements  

NASA Technical Reports Server (NTRS)

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

Lilie, Lyle; Bouley, Dan; Sivo, Chris

2006-01-01

336

Aircraft Cabin Turbulence Warning Experiment  

NASA Technical Reports Server (NTRS)

New turbulence prediction technology offers the potential for advance warning of impending turbulence encounters, thereby allowing necessary cabin preparation time prior to the encounter. The amount of time required for passengers and flight attendants to be securely seated (that is, seated with seat belts fastened) currently is not known. To determine secured seating-based warning times, a consortium of aircraft safety organizations have conducted an experiment involving a series of timed secured seating trials. This demonstrative experiment, conducted on October 1, 2, and 3, 2002, used a full-scale B-747 wide-body aircraft simulator, human passenger subjects, and supporting staff from six airlines. Active line-qualified flight attendants from three airlines participated in the trials. Definitive results have been obtained to provide secured seating-based warning times for the developers of turbulence warning technology

Bogue, Rodney K.; Larcher, Kenneth

2006-01-01

337

Perception of aircraft Deviation Cues  

NASA Technical Reports Server (NTRS)

To begin to address the need for new displays, required by a future airspace concept to support new roles that will be assigned to flight crews, a study of potentially informative display cues was undertaken. Two cues were tested on a simple plan display - aircraft trajectory and flight corridor. Of particular interest was the speed and accuracy with which participants could detect an aircraft deviating outside its flight corridor. Presence of the trajectory cue significantly reduced participant reaction time to a deviation while the flight corridor cue did not. Although non-significant, the flight corridor cue seemed to have a relationship with the accuracy of participants judgments rather than their speed. As this is the second of a series of studies, these issues will be addressed further in future studies.

Martin, Lynne; Azuma, Ronald; Fox, Jason; Verma, Savita; Lozito, Sandra

2005-01-01

338

Handbook of aircraft noise metrics  

NASA Technical Reports Server (NTRS)

Information is presented on 22 noise metrics that are associated with the measurement and prediction of the effects of aircraft noise. Some of the instantaneous frequency weighted sound level measures, such as A-weighted sound level, are used to provide multiple assessment of the aircraft noise level. Other multiple event metrics, such as day-night average sound level, were designed to relate sound levels measured over a period of time to subjective responses in an effort to determine compatible land uses and aid in community planning. The various measures are divided into: (1) instantaneous sound level metrics; (2) duration corrected single event metrics; (3) multiple event metrics; and (4) speech communication metrics. The scope of each measure is examined in terms of its: definition, purpose, background, relationship to other measures, calculation method, example, equipment, references, and standards.

Bennett, R. L.; Pearsons, K. S.

1981-01-01

339

Automation in civil transport aircraft.  

PubMed

The pilot of a contemporary transport aircraft is in a managerial role, supervising the performance of sophisticated systems which perform most of the tasks concerned with operating the aircraft safely and efficiently. Under normal conditions he is required to exercise his psycho-motor skills only to a very small extent; his principal task is to process information and to convey instructions to the automatics by way of push-button switches and similar devices. In the event of major system failure, however, or in the absence of ground-based facilities, he may be called upon to take a much more active part in control. The evolution of flight-deck automation owes much more to engineering and economic analyses that to systematic development of policy concerning the role of men in automated systems. The current situation is not without its problems, and substantial ergonomics input should contribute to future developments. PMID:15677242

Edwards, E

1977-12-01

340

CID Aircraft slap-down  

NASA Technical Reports Server (NTRS)

In this photograph the B-720 is seen during the moments of initial impact. The left wing is digging into the lakebed while the aircraft continues sliding towards wing openers. In 1984 NASA Dryden Flight Research Facility and the Federal Aviation Administration (FAA) teamed-up in a unique flight experiment called the Controlled Impact Demonstration (CID). The test involved crashing a Boeing 720 aircraft with four JT3C-7 engines burning a mixture of standard fuel with an additive, Anti-misting Kerosene (AMK), designed to supress fire. 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

341

Aircraft digital control design methods  

NASA Technical Reports Server (NTRS)

Variations in design methods for aircraft digital flight control are evaluated and compared. The methods fall into two categories; those where the design is done in the continuous domain (or s plane) and those where the design is done in the discrete domain (or z plane). Design method fidelity is evaluated by examining closed loop root movement and the frequency response of the discretely controlled continuous aircraft. It was found that all methods provided acceptable performance for sample rates greater than 10 cps except the uncompensated s plane design method which was acceptable above 20 cps. A design procedure based on optimal control methods was proposed that provided the best fidelity at very slow sample rates and required no design iterations for changing sample rates.

Powell, J. D.; Parsons, E.; Tashker, M. G.

1976-01-01

342

Electronically steerable antenna for aircraft  

NASA Astrophysics Data System (ADS)

The design of an electronically steerable medium gain antenna for aircraft able to provide voice communication via satellite is presented. The antenna consists of 5 radiating facets and the coverages achieved, including the effect of the aircraft fuselage, are based on the experimental results obtained with the actual components of the beam forming network (switches, phase shifters, power dividers) and the radiating facets including the matching network. One hundred percent of the mandatory coverage (colatitude 0 to 85 degrees) is achieved with a gain greater than 10 dBi and 12 dBi are achieved in 60 percent of it. Concerning the goal coverage (colatitude 0 to 105 degrees) a gain greater than 7 dBi is achieved in 84 percent of it. The dimensions of the radome required for this antenna are: length 1780 mm, width 255 mm, height 197 mm.

Barbero, J.; Hernanz, M. L.; Hernanz, M.; Martin, C.; Vassallo, J.; Hedge, B.

1991-10-01

343

Commercial-Aircraft Protection System  

Microsoft Academic Search

Recent world events have identified needs for a commercial aircraft defense system against Man-Portable Air Defense Systems (MANPADS), such as SA-7 and Stinger shoulder launched surface-to-air missiles. Technical challenges include target detection, identification and countermeasures. Political and societal challenges include cost, time to deployment, ground and air safety, and reliability. These challenges, as well as many others, have been met

Russell L. Case Jr.; Peter H. Wolff

2004-01-01

344

Fourth Aircraft Interior Noise Workshop  

NASA Technical Reports Server (NTRS)

The fourth in a series of NASA/SAE Interior Noise Workshops was held on May 19 and 20, 1992. The theme of the workshop was new technology and applications for aircraft noise with emphasis on source noise prediction; cabin noise prediction; cabin noise control, including active and passive methods; and cabin interior noise procedures. This report is a compilation of the presentations made at the meeting which addressed the above issues.

Stephens, David G. (compiler)

1992-01-01

345

Test-Bed Aircraft Scanner  

NASA Technical Reports Server (NTRS)

Test-bed aircraft multispectral scanner (TBAMS) is line-scanning multispectral imaging system with eight visible/near-infrared channels and one thermal-infrared channel. Key design features of TBAMS are its large size and modular subsystem mounted on horizontal baseplate. This unique layout allows easy access to and replacement of subsystems and their subcomponents. System designed around existing inexpensive parts, sacrifices compactness for ease of modification.

Jobson, D. J.; Katzberg, S. J.; Spiers, R. B.; Hardesty, C. A.; Burcher, E. E.; Irwin, S. H.

1982-01-01

346

Properties of aircraft tire materials  

NASA Technical Reports Server (NTRS)

A summary is presented of measured elastomeric composite response suitable for linear structural and thermoelastic analysis in aircraft tires. Both real and loss properties are presented for a variety of operating conditions including the effects of temperature and frequency. Suitable micro-mechanics models are used for predictions of these properties for other material combinations and the applicability of laminate theory is discussed relative to measured values.

Dodge, Richard N.; Clark, Samuel K.

1988-01-01

347

Oblique-wing supersonic aircraft  

NASA Technical Reports Server (NTRS)

An aircraft including a single fuselage having a main wing and a horizontal stabilizer airfoil pivotally attached at their centers to the fuselage is described. The pivotal attachments allow the airfoils to be yawed relative to the fuselage for high speed flight, and to be positioned at right angles with respect to the fuselage during takeoff, landing, and low speed flight. The main wing and the horizontal stabilizer are upwardly curved from their center pivotal connections towards their ends to form curvilinear dihedrals.

Jones, R. T. (inventor)

1976-01-01

348

VHF-UHF aircraft antenna  

Microsoft Academic Search

A broadband, circularly polarized antenna system suitable for use on WP-3 aircraft and operating in the VHF-UHF frequency region has been designed and fabricated. This airborne radiometer system will operate over a 3 to 1 frequency range without tuning. The installation contains a high- and low-frequency hemispherical coverage antenna and a high- and low-frequency fan-beam array. The entire installation is

F. Fine

1976-01-01

349

Process modeling KC-135 aircraft  

NASA Technical Reports Server (NTRS)

Instrumentation will be provided for KC-135 aircraft which will provide a quantitative measure of g-level variation during parabolic flights and its effect on experiments which demonstrate differences in results obtained with differences in convective flow. The flight apparatus will provide video recording of the effects of the g-level variations on varying fluid samples. The apparatus will be constructed to be available to fly on the KC-135 during most missions.

Workman, Gary L.

1991-01-01

350

Weather data dissemination to aircraft  

NASA Technical Reports Server (NTRS)

Documentation exists that shows weather to be responsible for approximately 40 percent of all general aviation accidents with fatalities. Weather data products available on the ground are becoming more sophisticated and greater in number. Although many of these data are critical to aircraft safety, they currently must be transmitted verbally to the aircraft. This process is labor intensive and provides a low rate of information transfer. Consequently, the pilot is often forced to make life-critical decisions based on incomplete and outdated information. Automated transmission of weather data from the ground to the aircraft can provide the aircrew with accurate data in near-real time. The current National Airspace System Plan calls for such an uplink capability to be provided by the Mode S Beacon System data link. Although this system has a very advanced data link capability, it will not be capable of providing adequate weather data to all airspace users in its planned configuration. This paper delineates some of the important weather data uplink system requirements, and describes a system which is capable of meeting these requirements. The proposed system utilizes a run-length coding technique for image data compression and a hybrid phase and amplitude modulation technique for the transmission of both voice and weather data on existing aeronautical Very High Frequency (VHF) voice communication channels.

Mcfarland, Richard H.; Parker, Craig B.

1990-01-01

351

Design Methods and Optimization for Morphing Aircraft  

NASA Technical Reports Server (NTRS)

This report provides a summary of accomplishments made during this research effort. The major accomplishments are in three areas. The first is the use of a multiobjective optimization strategy to help identify potential morphing features that uses an existing aircraft sizing code to predict the weight, size and performance of several fixed-geometry aircraft that are Pareto-optimal based upon on two competing aircraft performance objectives. The second area has been titled morphing as an independent variable and formulates the sizing of a morphing aircraft as an optimization problem in which the amount of geometric morphing for various aircraft parameters are included as design variables. This second effort consumed most of the overall effort on the project. The third area involved a more detailed sizing study of a commercial transport aircraft that would incorporate a morphing wing to possibly enable transatlantic point-to-point passenger service.

Crossley, William A.

2005-01-01

352

Aircraft Photovoltaic Power-Generating System.  

NASA Astrophysics Data System (ADS)

Photovoltaic cells, appropriately cooled and operating in the combustion-created high radiant-intensity environment of gas-turbine and jet engines, may replace the conventional (gearbox-driven) electrical power generators aboard jet aircraft. This study projects significant improvements not only in aircraft electrical power-generating-system performance, but also in overall aircraft performance. Jet -engine design modifications incorporating this concept not only save weight (and thus fuel), but are--in themselves --favorable to jet-engine performance. The dissertation concentrates on operational, constructional, structural, thermal, optical, radiometrical, thin-film, and solid-state theoretical aspects of the overall project. This new electrical power-generating system offers solid-state reliability with electrical power-output capability comparable to that of existing aircraft electromechanical power-generating systems (alternators and generators). In addition to improvements in aircraft performance, significant aircraft fuel- and weight-saving advantages are projected.

Doellner, Oscar Leonard

353

Advanced technology for future regional transport aircraft  

NASA Technical Reports Server (NTRS)

In connection with a request for a report coming from a U.S. Senate committee, NASA formed a Small Transport Aircraft Technology (STAT) team in 1978. STAT was to obtain information concerning the technical improvements in commuter aircraft that would likely increase their public acceptance. Another area of study was related to questions regarding the help which could be provided by NASA's aeronautical research and development program to commuter aircraft manufacturers with respect to the solution of technical problems. Attention is given to commuter airline growth, current commuter/region aircraft and new aircraft in development, prospects for advanced technology commuter/regional transports, and potential benefits of advanced technology. A list is provided of a number of particular advances appropriate to small transport aircraft, taking into account small gas turbine engine component technology, propeller technology, three-dimensional wing-design technology, airframe aerodynamics/propulsion integration, and composite structure materials.

Williams, L. J.

1982-01-01

354

:' ' V-g Records from Vampire Aircraft  

E-print Network

Summary.--Four hundred and sixty-one V-g records covering 923 flying hours were taken from Vampire aircraft operating ~n England and Germany during the period March to October, 1951. V-g boundaries expected to be exceeded once in 30, 100 and 300 hours are estimated, special consideration being given to aircraft engaged on ground-attack duties. The results confirm the general belief that more severe accelerations and higher speeds may be expected when aircraft are on ground attack duties than when they are on other duties. 1. Introduction.--V-g recorders are fitted in Vampire aircraft operating from two stations (Odiham and North Weald) in England and three stations (Gutersloh, Wunstorf and Celle) in Germany. The records show the maximum speeds and extreme normal accelerations reached by the aircraft in the course of their ordinary flying duties. This analysis covers 297 records (791 flying hours) from home-based aircraft and 164 records

M. No; E. Marjorie Owen; B. Sc; J. R. Heath-smith; B. Sc

1952-01-01

355

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

356

Formal Verification of Distributed Aircraft Controllers Sarah M. Loos  

E-print Network

not be aware of. Because these safety guarantees always hold, the aircraft are protected against unexpected-avoidance controllers for aircraft systems. We want to prove safety not just for a single aircraft or a pair of aircraft. Aircraft control systems are safety-critical, so they must be de- signed with a high assurance

Platzer, André

357

32 CFR 855.6 - Aircraft exempt from the requirement for a civil aircraft landing permit.  

Code of Federal Regulations, 2011 CFR

...Government has retained liability responsibilities. (7) Civil aircraft transporting critically ill or injured individuals or transplant organs to or from an Air Force installation. (8) Historic aircraft being delivered for Air Force museum exhibits...

2011-07-01

358

32 CFR 855.6 - Aircraft exempt from the requirement for a civil aircraft landing permit.  

Code of Federal Regulations, 2012 CFR

...Government has retained liability responsibilities. (7) Civil aircraft transporting critically ill or injured individuals or transplant organs to or from an Air Force installation. (8) Historic aircraft being delivered for Air Force museum exhibits...

2012-07-01

359

78 FR 54385 - Airworthiness Directives; Various Aircraft Equipped With Rotax Aircraft Engines 912 A Series Engine  

Federal Register 2010, 2011, 2012, 2013, 2014

...rotax-aircraft-engines.com...production test run, a non-compliance...installed cylinder head assembly of...number of engines. The affected...significant economic impact, positive...Rotax Aircraft Engines 912 A series...N) 623682 cylinder head...

2013-09-04

360

Approaches to Representing Aircraft Fuel Efficiency Performance for the Purpose of a Commercial Aircraft Certification Standard  

E-print Network

Increasing concern over the potential harmful effects of green house gas emissions from various sources has motivated the consideration of an aircraft certification standard as one way to reduce aircraft CO2 emissions and ...

Yutko, Brian

2011-06-27

361

Approaches to representing aircraft fuel efficiency performance for the purpose of a commercial aircraft certification standard  

E-print Network

Increasing concern over the potential harmful effects of green house gas emissions from various sources has motivated the consideration of an aircraft certification standard as one way to reduce aircraft C02 emissions and ...

Yutko, Brian M. (Brian Matthew)

2011-01-01

362

Aircraft Radiation Shield Experiments— Preflight Laboratory Testing  

Microsoft Academic Search

In the past, measurements onboard a research Boeing 57F(RB57-F) aircraft have demonstrated that the neutron environmentwithin the aircraft structure is greater than that in the local externalenvironment. Recent studies onboard Boeing 737 commercial flightshave demonstrated cabin variations in radiation exposure up to30 percent. These prior results were the basis of the present study toquantify the potential effects of aircraft construction

Robert C. Singleterry; Judy L. Shinn; John W. Wilson; Donald L. Maiden; Sheila A. Thibeault; Francis F. Badavi

1999-01-01

363

Cooperative Electronic Chaining Using Small Unmanned Aircraft  

Microsoft Academic Search

When using a team of small unmanned aircraft, with no satellite communications, the operational range of the team is typically limited by line-of-sight communication constraints between an individual aircraft and a ground station, and not the endurance range of the in- dividual aircraft within the team. By using electronic chaining to form a multi-hop commu- nication link using the team,

Cory R. Dixon; Eric W. Frewy

2007-01-01

364

Life prediction of aging aircraft wiring systems  

NASA Technical Reports Server (NTRS)

The program goal is to develop a computerized life prediction model capable of identifying present aging progress and predicting end of life for aircraft wiring. A summary is given in viewgraph format of progress made on phase 1 objectives, which were to identify critical aircraft wiring problems; relate most common failures identified to the wire mechanism causing the failure; assess wiring requirments, materials, and stress environment for fighter aircraft; and demonstrate the feasibility of a time-temperature-environment model.

Slenski, George

1995-01-01

365

Maintenance cost study of rotary wing aircraft  

NASA Technical Reports Server (NTRS)

The feasibility was studied of predicting rotary wing operation maintenance costs by using several aircraft design factors for the aircraft dynamic systems. The dynamic systems considered were engines, drives and transmissions, rotors, and flight controls. Multiple regression analysis was used to correlate aircraft design and operational factors with manhours per flight hour, and equations for each dynamic system were developed. Results of labor predictions using the equations compare favorably with actual values.

1977-01-01

366

Aircraft-Specific Thermoelectric Generator Module  

Microsoft Academic Search

Autonomous sensor nodes for wireless sensor networks are currently under discussion for aircraft structural health monitoring.\\u000a Self-sufficient operation of a sensor node requires a positive power budget for sensing, processing, and communication tasks.\\u000a Energy harvesting for autonomous powering by thermoelectric devices depends strongly on maintaining the temperature difference\\u000a within the aircraft operation envelope. Aircraft pass through huge outside temperature variations

D. Samson; T. Otterpohl; M. Kluge; U. Schmid; Th. Becker

2010-01-01

367

Aircraft Photovoltaic Power-Generating System  

Microsoft Academic Search

Photovoltaic cells, appropriately cooled and operating in the combustion-created high radiant-intensity environment of gas-turbine and jet engines, may replace the conventional (gearbox-driven) electrical power generators aboard jet aircraft. This study projects significant improvements not only in aircraft electrical power-generating-system performance, but also in overall aircraft performance. Jet -engine design modifications incorporating this concept not only save weight (and thus fuel),

Oscar Leonard Doellner

1991-01-01

368

Aircraft photovoltaic power-generating system  

Microsoft Academic Search

Photovoltaic cells, appropriately cooled and operating in the combustion-created high radiant-intensity environment of gas-turbine and jet engines, may replace the conventional (gearbox-driven) electrical power generators aboard jet aircraft. This study projects significant improvements not only in aircraft electrical power-generating-system performance, but also in overall aircraft performance. Jet-engine design modifications incorporating this concept not only save weight (and thus fuel), but

Oscar Leonard Doellner

1991-01-01

369

Electrical power generation systems - Combat aircraft perspective  

NASA Astrophysics Data System (ADS)

The electrical power generation system requirements of combat aircraft are briefly examined. In particular, attention is given to customer requirements, development of the installed electrical power in aircraft, electrical load analysis for designing the power generation system, and definition of aircraft electrical power supply characteristics and consumer qualities. The discussion also covers reliability requirements for power generation systems, design of a power generation system, control and protection equipment in power generation systems, and helicopter electrical power systems.

Moeller, R.

370

The History of Aircraft Materials Presentation  

NSDL National Science Digital Library

This PowerPoint document from the Aerospace Manufacturing Education Project provides a solid background of the history of materials used in the aircraft industry. The presentation includes 28 slides and covers the types of materials used throughout the history of the aircraft industry, why materials were adopted at different points in time, why materials have been replaced by new technologies and what the future is for materials in aircraft. Many useful graphics and photographs are included.

2011-11-17

371

Challenges for the aircraft structural integrity program  

NASA Technical Reports Server (NTRS)

Thirty-six years ago the United States Air Force established the USAF Aircraft Structural Integrity Program (ASIP) because flight safety had been degraded by fatigue failures of operational aircraft. This initial program evolved, but has been stable since the issuance of MIL-STD-1530A in 1975. Today, the program faces new challenges because of a need to maintain aircraft longer in an environment of reduced funding levels. Also, there is increased pressure to reduce cost of the acquisition of new aircraft. It is the purpose of this paper to discuss the challenges for the ASIP and identify the changes in the program that will meet these challenges in the future.

Lincoln, John W.

1994-01-01

372

Aircraft-type dependency of contrail evolution  

NASA Astrophysics Data System (ADS)

The impact of aircraft type on contrail evolution is assessed using a large eddy simulation model with Lagrangian ice microphysics. Six different aircraft ranging from the small regional airliner Bombardier CRJ to the largest aircraft Airbus A380 are taken into account. Differences in wake vortex properties and fuel flow lead to considerable variations in the early contrail geometric depth and ice crystal number. Larger aircraft produce contrails with more ice crystals (assuming that the number of initially generated ice crystals per kilogram fuel is constant). These initial differences are reduced in the first minutes, as the ice crystal loss during the vortex phase is stronger for larger aircraft. In supersaturated air, contrails of large aircraft are much deeper after 5 min than those of small aircraft. A parameterization for the final vertical displacement of the wake vortex system is provided, depending only on the initial vortex circulation and stratification. Cloud resolving simulations are used to examine whether the aircraft-induced initial differences have a long-lasting mark. These simulations suggest that the synoptic scenario controls the contrail cirrus evolution qualitatively. However, quantitative differences between the contrail cirrus properties of the various aircraft remain over the total simulation period of 6 h. The total extinctions of A380-produced contrails are about 1.5 to 2.5 times higher than those from contrails of a Bombardier CRJ.

Unterstrasser, S.; Görsch, N.

2014-12-01

373

Modal control of relaxed static stability aircraft  

NASA Technical Reports Server (NTRS)

A method is developed that assigns a selected portion of a closed loop system eigenstructure in accordance with certain desirable criteria. The method is applied here to a relaxed static stability aircraft, the goal being to synthesize a control law that provides the unstable aircraft with handling qualities equal to or better than those of a comparable statically stable aircraft. It is shown that by using the target system eigenstructure, good flight characteristics are achieved by the unstable aircraft. It is also shown that improved characteristics can be obtained by assigning an orthogonal eigenvector structure.

Rooney, R. H.; Chung, J. C.; Shapiro, E. Y.

1982-01-01

374

The F-18 systems research aircraft facility  

NASA Technical Reports Server (NTRS)

To help ensure that new aerospace initiatives rapidly transition to competitive U.S. technologies, NASA Dryden Flight Research Facility has dedicated a systems research aircraft facility. The primary goal is to accelerate the transition of new aerospace technologies to commercial, military, and space vehicles. Key technologies include more-electric aircraft concepts, fly-by-light systems, flush airdata systems, and advanced computer architectures. Future aircraft that will benefit are the high-speed civil transport and the National AeroSpace Plane. This paper describes the systems research aircraft flight research vehicle and outlines near-term programs.

Sitz, Joel R.

1992-01-01

375

Aircraft Emissions at Cruise and Plume Processes  

NASA Astrophysics Data System (ADS)

The detection of aircraft emissions at cruise altitudes helps to understand and assess the effects of aviation on atmospheric composition and climate. Since the early 1990s, aircraft emissions of carbon dioxide, water vapor, nitrogen and sulfur oxides, aerosol and soot and their processing in the atmosphere as well as contrail formation have been measured in situ with the instrumented DLR research aircraft Falcon. Scientific results from a series of aircraft missions are summarized and explained, uncertainties are discussed and suggestions are made on how to move forward.

Voigt, Christiane; Jurkat, Tina; Schlager, Hans; Schäuble, Dominik; Petzold, Andreas; Schumann, Ulrich

376

An Assessment of Commuter Aircraft Noise Impact  

NASA Technical Reports Server (NTRS)

This report examines several approaches to understanding 'the commuter aircraft noise problem.' The commuter aircraft noise problem in the sense addressed in this report is the belief that some aspect(s) of community response to noise produced by commuter aircraft operations may not be fully assessed by conventional environmental noise metrics and methods. The report offers alternate perspectives and approaches for understanding this issue. The report also develops a set of diagnostic screening questions; describes commuter aircraft noise situations at several airports; and makes recommendations for increasing understanding of the practical consequences of greater heterogeneity in the air transport fleet serving larger airports.

Fidell, Sanford; Pearsons, Karl S.; Silvati, Laura; Sneddon, Matthew

1996-01-01

377

Electromagnetic Propagation Prediction Inside Aircraft Cabins  

NASA Technical Reports Server (NTRS)

Electromagnetic propagation models for signal strength prediction within aircraft cabins are essential for evaluating and designing a wireless communication system to be implemented onboard aircraft. A model was developed using Wireless Valley's SitePlanner; which is commercial grade software intended for predictions within office buildings. The performance of the model was evaluated through a comparison with test data measurements taken on several aircraft. The comparison concluded that the model can accurately predict power propagation within the cabin. This model can enhance researchers understanding of power propagation within aircraft cabins and will aid in future research.

Hankins, Genevieve; Vahala, Linda; Beggs, John H.

2004-01-01

378

Alternate Fuels for Use in Commercial Aircraft  

NASA Technical Reports Server (NTRS)

The engine and aircraft Research and Development (R&D) communities have been investigating alternative fueling in near-term, midterm, and far-term aircraft. A drop in jet fuel replacement, consisting of a kerosene (Jet-A) and synthetic fuel blend, will be possible for use in existing and near-term aircraft. Future midterm aircraft may use a biojet and synthetic fuel blend in ultra-efficient airplane designs. Future far-term engines and aircraft in 50-plus years may be specifically designed to use a low- or zero-carbon fuel. Synthetic jet fuels from coal, natural gas, or other hydrocarbon feedstocks are very similar in performance to conventional jet fuel, yet the additional CO2 produced during the manufacturing needs to be permanently sequestered. Biojet fuels need to be developed specifically for jet aircraft without displacing food production. Envisioned as midterm aircraft fuel, if the performance and cost liabilities can be overcome, biofuel blends with synthetic jet or Jet-A fuels have near-term potential in terms of global climatic concerns. Long-term solutions address dramatic emissions reductions through use of alternate aircraft fuels such as liquid hydrogen or liquid methane. Either of these new aircraft fuels will require an enormous change in infrastructure and thus engine and airplane design. Life-cycle environmental questions need to be addressed.

Daggett, David L.; Hendricks, Robert C.; Walther, Rainer; Corporan, Edwin

2008-01-01

379

The NASA Aircraft Energy Efficiency Program  

NASA Technical Reports Server (NTRS)

The objective of the NASA Aircraft Energy Efficiency Program is to accelerate the development of advanced technology for more energy-efficient subsonic transport aircraft. This program will have application to current transport derivatives in the early 1980s and to all-new aircraft of the late 1980s and early 1990s. Six major technology projects were defined that could result in fuel savings in commercial aircraft: (1) Engine Component Improvement, (2) Energy Efficient Engine, (3) Advanced Turboprops, (4) Energy Efficiency Transport (aerodynamically speaking), (5) Laminar Flow Control, and (6) Composite Primary Structures.

Klineberg, J. M.

1978-01-01

380

32 CFR 855.6 - Aircraft exempt from the requirement for a civil aircraft landing permit.  

Code of Federal Regulations, 2010 CFR

...as a Coast Guard Auxiliary aircraft. The pilot will always be...Auxiliary Patrol Order. If the aircraft is operating under “verbal...support of operations involving safety of life or property as a result...responsibilities. (7) Civil aircraft transporting critically...

2010-07-01

381

32 CFR 855.6 - Aircraft exempt from the requirement for a civil aircraft landing permit.  

Code of Federal Regulations, 2013 CFR

...as a Coast Guard Auxiliary aircraft. The pilot will always be...Auxiliary Patrol Order. If the aircraft is operating under “verbal...support of operations involving safety of life or property as a result...responsibilities. (7) Civil aircraft transporting critically...

2013-07-01

382

32 CFR 855.6 - Aircraft exempt from the requirement for a civil aircraft landing permit.  

Code of Federal Regulations, 2014 CFR

...as a Coast Guard Auxiliary aircraft. The pilot will always be...Auxiliary Patrol Order. If the aircraft is operating under “verbal...support of operations involving safety of life or property as a result...responsibilities. (7) Civil aircraft transporting critically...

2014-07-01

383

Aircraft empennage structural detail design  

NASA Technical Reports Server (NTRS)

This project involved the detailed design of the aft fuselage and empennage structure, vertical stabilizer, rudder, horizontal stabilizer, and elevator for the Triton primary flight trainer. The main design goals under consideration were to illustrate the integration of the control systems devices used in the tail surfaces and their necessary structural supports as well as the elevator trim, navigational lighting system, electrical systems, tail-located ground tie, and fuselage/cabin interface structure. Accommodations for maintenance, lubrication, adjustment, and repairability were devised. Weight, fabrication, and (sub)assembly goals were addressed. All designs were in accordance with the FAR Part 23 stipulations for a normal category aircraft.

Meholic, Greg; Brown, Rhonda; Hall, Melissa; Harvey, Robert; Singer, Michael; Tella, Gustavo

1993-01-01

384

Cyberinfrastructure for Aircraft Mission Support  

NASA Technical Reports Server (NTRS)

Forth last several years NASA's Airborne Science Program has been developing and using infrastructure and applications that enable researchers to interact with each other and with airborne instruments via network communications. Use of these tools has increased near realtime situational awareness during field operations, resulting it productivity improvements, improved decision making, and the collection of better data. Advances in pre-mission planning and post-mission access have also emerged. Integrating these capabilities with other tools to evolve coherent service-oriented enterprise architecture for aircraft flight and test operations is the subject of ongoing efforts.

Freudinger, Lawrence C.

2010-01-01

385

Heat generation in aircraft tires  

NASA Technical Reports Server (NTRS)

A method was developed for calculating the internal temperature distribution in an aircraft tire while free rolling under load. The method uses an approximate stress analysis of each point in the tire as it rolls through the contact patch, and from this stress change the mechanical work done on each volume element may be obtained and converted into a heat release rate through a knowledge of material characteristics. The tire cross-section is then considered as a body with internal heat generation, and the diffusion equation is solved numerically with appropriate boundary conditions of the wheel and runway surface. Comparison with data obtained with buried thermocouples in tires shows good agreement.

Clark, S. K.; Dodge, R. N.

1985-01-01

386

Innovative Materials for Aircraft Morphing  

NASA Technical Reports Server (NTRS)

Reported herein is an overview of the research being conducted within the Materials Division at NASA Langley Research Center on the development of smart material technologies for advanced airframe systems. The research is a part of the Aircraft Morphing Program which is a new six-year research program to develop smart components for self-adaptive airframe systems. The fundamental areas of materials research within the program are computational materials; advanced piezoelectric materials; advanced fiber optic sensing techniques; and fabrication of integrated composite structures. This paper presents a portion of the ongoing research in each of these areas of materials research.

Simpson, J. O.; Wise, S. A.; Bryant, R. G.; Cano, R. J.; Gates, T. S.; Hinkley, J. A.; Rogowski, R. S.; Whitley, K. S.

1997-01-01

387

Technology for aircraft energy efficiency  

NASA Technical Reports Server (NTRS)

Six technology programs for reducing fuel use in U.S. commercial aviation are discussed. The six NASA programs are divided into three groups: Propulsion - engine component improvement, energy efficient engine, advanced turboprops; Aerodynamics - energy efficient transport, laminar flow control; and Structures - composite primary structures. Schedules, phases, and applications of these programs are considered, and it is suggested that program results will be applied to current transport derivatives in the early 1980s and to all-new aircraft of the late 1980s and early 1990s.

Klineberg, J. M.

1977-01-01

388

14 CFR 252.11 - Aircraft on the ground.  

Code of Federal Regulations, 2011 CFR

...PROCEEDINGS) ECONOMIC REGULATIONS SMOKING ABOARD AIRCRAFT § 252.11 Aircraft... (a) Air carriers shall prohibit smoking whenever the aircraft is on the ground. (b) With respect to the restrictions on smoking described in § 252.5, foreign air...

2011-01-01

389

14 CFR 252.11 - Aircraft on the ground.  

Code of Federal Regulations, 2010 CFR

...PROCEEDINGS) ECONOMIC REGULATIONS SMOKING ABOARD AIRCRAFT § 252.11 Aircraft... (a) Air carriers shall prohibit smoking whenever the aircraft is on the ground. (b) With respect to the restrictions on smoking described in § 252.5, foreign air...

2010-01-01

390

76 FR 48047 - Airworthiness Directives; Diamond Aircraft Industries Powered Sailplanes  

Federal Register 2010, 2011, 2012, 2013, 2014

...flight of civil aircraft in air commerce...finds necessary for safety in air commerce...transportation, Aircraft, Aviation safety, Incorporation...European Aviation Safety Agency (EASA...2011; Diamond Aircraft Industries...

2011-08-08

391

31 CFR 538.519 - Aircraft and maritime safety.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Aircraft and maritime safety. 538.519 Section...Policy § 538.519 Aircraft and maritime safety. Specific licenses...commercial passenger aircraft, and to ensure the safety of ocean-going...

2012-07-01

392

47 CFR 87.191 - Foreign aircraft stations.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Foreign aircraft stations. 87.191 Section...COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AVIATION SERVICES Aircraft Stations § 87.191 Foreign aircraft stations. (a)...

2010-10-01

393

49 CFR 175.9 - Special aircraft operations.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Special aircraft operations. 175.9 Section...PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT...MATERIALS REGULATIONS CARRIAGE BY AIRCRAFT General Information and Regulations § 175.9 Special aircraft operations. (a)...

2013-10-01

394

31 CFR 538.519 - Aircraft and maritime safety.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Aircraft and maritime safety. 538.519 Section...Policy § 538.519 Aircraft and maritime safety. Specific licenses...commercial passenger aircraft, and to ensure the safety of ocean-going...

2010-07-01

395

47 CFR 87.191 - Foreign aircraft stations.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 false Foreign aircraft stations. 87.191 Section...COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AVIATION SERVICES Aircraft Stations § 87.191 Foreign aircraft stations. (a)...

2012-10-01

396

77 FR 19061 - Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes  

Federal Register 2010, 2011, 2012, 2013, 2014

...flight of civil aircraft in air commerce...finds necessary for safety in air commerce...transportation, Aircraft, Aviation safety, Incorporation...European Aviation Safety Agency (EASA...2011, and Pilatus Aircraft Ltd. PC-6...

2012-03-30

397

31 CFR 538.519 - Aircraft and maritime safety.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Aircraft and maritime safety. 538.519 Section...Policy § 538.519 Aircraft and maritime safety. Specific licenses...commercial passenger aircraft, and to ensure the safety of ocean-going...

2011-07-01

398

78 FR 42723 - Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes  

Federal Register 2010, 2011, 2012, 2013, 2014

...flight of civil aircraft in air commerce...finds necessary for safety in air commerce...transportation, Aircraft, Aviation safety, Incorporation...European Aviation Safety Agency (EASA...contact Pilatus Aircraft LTD.,...

2013-07-17

399

47 CFR 87.191 - Foreign aircraft stations.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Foreign aircraft stations. 87.191 Section...COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AVIATION SERVICES Aircraft Stations § 87.191 Foreign aircraft stations. (a)...

2011-10-01

400

47 CFR 87.191 - Foreign aircraft stations.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Foreign aircraft stations. 87.191 Section...COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AVIATION SERVICES Aircraft Stations § 87.191 Foreign aircraft stations. (a)...

2013-10-01

401

31 CFR 538.519 - Aircraft and maritime safety.  

Code of Federal Regulations, 2014 CFR

...2014-07-01 false Aircraft and maritime safety. 538.519 Section...Policy § 538.519 Aircraft and maritime safety. Specific licenses...commercial passenger aircraft, and to ensure the safety of ocean-going...

2014-07-01

402

49 CFR 175.9 - Special aircraft operations.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 false Special aircraft operations. 175.9 Section...PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT...MATERIALS REGULATIONS CARRIAGE BY AIRCRAFT General Information and Regulations § 175.9 Special aircraft operations. (a)...

2014-10-01

403

31 CFR 538.519 - Aircraft and maritime safety.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Aircraft and maritime safety. 538.519 Section...Policy § 538.519 Aircraft and maritime safety. Specific licenses...commercial passenger aircraft, and to ensure the safety of ocean-going...

2013-07-01

404

47 CFR 90.423 - Operation on board aircraft.  

Code of Federal Regulations, 2013 CFR

... false Operation on board aircraft. 90.423 Section 90...COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES...423 Operation on board aircraft. (a) Except as...part may be operated aboard aircraft for air-to-mobile,...

2013-10-01

405

78 FR 11572 - Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes  

Federal Register 2010, 2011, 2012, 2013, 2014

...flight of civil aircraft in air commerce...finds necessary for safety in air commerce...transportation, Aircraft, Aviation safety, Incorporation...European Aviation Safety Agency (EASA...2012; Pilatus Aircraft Ltd. Service...

2013-02-19

406

49 CFR 175.9 - Special aircraft operations.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 false Special aircraft operations. 175.9 Section...PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT...MATERIALS REGULATIONS CARRIAGE BY AIRCRAFT General Information and Regulations § 175.9 Special aircraft operations. (a)...

2012-10-01

407

47 CFR 90.423 - Operation on board aircraft.  

Code of Federal Regulations, 2012 CFR

... false Operation on board aircraft. 90.423 Section 90...COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES...423 Operation on board aircraft. (a) Except as...part may be operated aboard aircraft for air-to-mobile,...

2012-10-01

408

49 CFR 175.9 - Special aircraft operations.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Special aircraft operations. 175.9 Section...PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT...MATERIALS REGULATIONS CARRIAGE BY AIRCRAFT General Information and Regulations § 175.9 Special aircraft operations. (a)...

2011-10-01

409

14 CFR 47.61 - Dealers' Aircraft Registration Certificates.  

Code of Federal Regulations, 2010 CFR

...false Dealers' Aircraft Registration Certificates. 47.61 Section 47.61 Aeronautics...REGISTRATION Dealers' Aircraft Registration Certificate § 47.61 Dealers' Aircraft Registration Certificates. (a) The FAA issues a...

2010-01-01

410

Active Sensing by Unmanned Aircraft Systems in Realistic Communication  

E-print Network

Active Sensing by Unmanned Aircraft Systems in Realistic Communication Environments Eric W. Frew-theoretic framework for active sensing by unmanned aircraft systems in realistic communication environments of the active sensing framework. Keywords: active sensing, unmanned aircraft systems, stochastic approximation

Frew, Eric W.

411

14 CFR 291.22 - Aircraft accident liability insurance requirement.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 2011-01-01 false Aircraft accident liability insurance requirement. 291...Transportation § 291.22 Aircraft accident liability insurance requirement...carrier has and maintains in effect aircraft accident liability coverage that meets the...

2011-01-01

412

14 CFR 294.40 - Aircraft accident liability insurance requirements.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 2011-01-01 false Aircraft accident liability insurance requirements. ...Requirements § 294.40 Aircraft accident liability insurance requirements. ...carrier has and maintains in effect aircraft accident liability coverage that meets...

2011-01-01

413

14 CFR 294.40 - Aircraft accident liability insurance requirements.  

Code of Federal Regulations, 2014 CFR

...2014-01-01 2014-01-01 false Aircraft accident liability insurance requirements. ...Requirements § 294.40 Aircraft accident liability insurance requirements. ...carrier has and maintains in effect aircraft accident liability coverage that meets...

2014-01-01

414

14 CFR 294.40 - Aircraft accident liability insurance requirements.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 2013-01-01 false Aircraft accident liability insurance requirements. ...Requirements § 294.40 Aircraft accident liability insurance requirements. ...carrier has and maintains in effect aircraft accident liability coverage that meets...

2013-01-01

415

47 CFR 87.51 - Aircraft earth station commissioning.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Aircraft earth station commissioning. 87.51 Section...Applications and Licenses § 87.51 Aircraft earth station commissioning. (a) [Reserved] (b) Aircraft earth stations authorized to operate...

2013-10-01

416

47 CFR 87.51 - Aircraft earth station commissioning.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Aircraft earth station commissioning. 87.51 Section...Applications and Licenses § 87.51 Aircraft earth station commissioning. (a) [Reserved] (b) Aircraft earth stations authorized to operate...

2010-10-01

417

47 CFR 87.51 - Aircraft earth station commissioning.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Aircraft earth station commissioning. 87.51 Section...Applications and Licenses § 87.51 Aircraft earth station commissioning. (a) [Reserved] (b) Aircraft earth stations authorized to operate...

2011-10-01

418

47 CFR 87.51 - Aircraft earth station commissioning.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Aircraft earth station commissioning. 87.51 Section...Applications and Licenses § 87.51 Aircraft earth station commissioning. (a) [Reserved] (b) Aircraft earth stations authorized to operate...

2012-10-01

419

78 FR 9796 - Airworthiness Directives; Cessna Aircraft Company Airplanes  

Federal Register 2010, 2011, 2012, 2013, 2014

...2120-AA64 Airworthiness Directives; Cessna Aircraft Company Airplanes AGENCY: Federal Aviation...airworthiness directive (AD) for certain Cessna Aircraft Company Models 172R and 172S airplanes...identified in this AD, contact Cessna Aircraft Company, Customer service,...

2013-02-12

420

Aircraft Engine Performance Study Using Flight Data Recorder Archives  

E-print Network

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

Gummadi, Ramakrishna

421

49 CFR 1544.225 - Security of aircraft and facilities.  

Code of Federal Regulations, 2014 CFR

... 2014-10-01 false Security of aircraft and facilities. 1544.225 Section...SECURITY CIVIL AVIATION SECURITY AIRCRAFT OPERATOR SECURITY: AIR CARRIERS AND...Operations § 1544.225 Security of aircraft and facilities. Each...

2014-10-01

422

19 CFR 122.41 - Aircraft required to enter.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Aircraft required to enter. 122.41 Section...TREASURY AIR COMMERCE REGULATIONS Aircraft Entry and Entry Documents; Electronic...Non-Crew Members Onboard Commercial Aircraft Arriving In, Continuing Within,...

2013-04-01

423

49 CFR 1544.225 - Security of aircraft and facilities.  

Code of Federal Regulations, 2013 CFR

... 2013-10-01 false Security of aircraft and facilities. 1544.225 Section...SECURITY CIVIL AVIATION SECURITY AIRCRAFT OPERATOR SECURITY: AIR CARRIERS AND...Operations § 1544.225 Security of aircraft and facilities. Each...

2013-10-01

424

78 FR 24689 - Airworthiness Directives; PILATUS Aircraft Ltd. Airplanes  

Federal Register 2010, 2011, 2012, 2013, 2014

...2120-AA64 Airworthiness Directives; PILATUS Aircraft Ltd. Airplanes AGENCY: Federal Aviation...airworthiness directive (AD) for all PILATUS Aircraft Ltd. Model PC-7 airplanes. This proposed...in this proposed AD, contact PILATUS AIRCRAFT LTD., Customer Technical...

2013-04-26

425

49 CFR 1544.225 - Security of aircraft and facilities.  

Code of Federal Regulations, 2011 CFR

... 2011-10-01 false Security of aircraft and facilities. 1544.225 Section...SECURITY CIVIL AVIATION SECURITY AIRCRAFT OPERATOR SECURITY: AIR CARRIERS AND...Operations § 1544.225 Security of aircraft and facilities. Each...

2011-10-01

426

49 CFR 1544.225 - Security of aircraft and facilities.  

Code of Federal Regulations, 2010 CFR

... 2010-10-01 false Security of aircraft and facilities. 1544.225 Section...SECURITY CIVIL AVIATION SECURITY AIRCRAFT OPERATOR SECURITY: AIR CARRIERS AND...Operations § 1544.225 Security of aircraft and facilities. Each...

2010-10-01

427

49 CFR 1544.225 - Security of aircraft and facilities.  

Code of Federal Regulations, 2012 CFR

... 2012-10-01 false Security of aircraft and facilities. 1544.225 Section...SECURITY CIVIL AVIATION SECURITY AIRCRAFT OPERATOR SECURITY: AIR CARRIERS AND...Operations § 1544.225 Security of aircraft and facilities. Each...

2012-10-01

428

19 CFR 122.41 - Aircraft required to enter.  

Code of Federal Regulations, 2014 CFR

...2014-04-01 2014-04-01 false Aircraft required to enter. 122.41 Section...TREASURY AIR COMMERCE REGULATIONS Aircraft Entry and Entry Documents; Electronic...Non-Crew Members Onboard Commercial Aircraft Arriving In, Continuing Within,...

2014-04-01

429

19 CFR 122.41 - Aircraft required to enter.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Aircraft required to enter. 122.41 Section...TREASURY AIR COMMERCE REGULATIONS Aircraft Entry and Entry Documents; Electronic...Non-Crew Members Onboard Commercial Aircraft Arriving In, Continuing Within,...

2011-04-01

430

AIRCRAFT SERIOUS INCIDENT REPORT OCCURRENCE NUMBER 00/2518  

E-print Network

AIRCRAFT SERIOUS INCIDENT REPORT OCCURRENCE NUMBER 00/2518 B767-319ER ZK-NCJ NZ 60 `ERRONEOUS ................................................................................................... 23 1.3 Damage to Aircraft) ................................................................................................. 26 1.6 Aircraft Information

Ladkin, Peter B.

431

14 CFR 121.153 - Aircraft requirements: General.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 2011-01-01 false Aircraft requirements: General. 121.153 Section...DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Aircraft Requirements § 121.153 Aircraft requirements: General. (a) Except...

2011-01-01

432

78 FR 37448 - Airworthiness Directives; Cessna Aircraft Company Airplanes  

Federal Register 2010, 2011, 2012, 2013, 2014

...2120-AA64 Airworthiness Directives; Cessna Aircraft Company Airplanes AGENCY: Federal Aviation...airworthiness directive (AD) for certain Cessna Aircraft Company (Cessna) (previously COLUMBIA...identified in this AD, contact Cessna Aircraft Company, Customer Service,...

2013-06-21

433

78 FR 58874 - Airworthiness Directives; PILATUS AIRCRAFT LTD. Airplanes  

Federal Register 2010, 2011, 2012, 2013, 2014

...2120-AA64 Airworthiness Directives; PILATUS AIRCRAFT LTD. Airplanes AGENCY: Federal Aviation...airworthiness directive (AD) for PILATUS AIRCRAFT LTD. Model PC-12/47E airplanes...identified in this AD, contact Pilatus Aircraft Ltd., Customer Service Manager,...

2013-09-25

434

32 CFR 855.15 - Detaining an aircraft.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Detaining an aircraft. 855.15 Section 855.15 National Defense...Defense (Continued) DEPARTMENT OF THE AIR FORCE AIRCRAFT CIVIL AIRCRAFT USE OF UNITED STATES AIR FORCE AIRFIELDS...

2010-07-01

435

32 CFR 855.15 - Detaining an aircraft.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 2012-07-01 false Detaining an aircraft. 855.15 Section 855.15 National Defense...Defense (Continued) DEPARTMENT OF THE AIR FORCE AIRCRAFT CIVIL AIRCRAFT USE OF UNITED STATES AIR FORCE AIRFIELDS...

2012-07-01

436

14 CFR 121.153 - Aircraft requirements: General.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 2013-01-01 false Aircraft requirements: General. 121.153 Section...DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Aircraft Requirements § 121.153 Aircraft requirements: General. (a) Except...

2013-01-01

437

32 CFR 855.15 - Detaining an aircraft.  

Code of Federal Regulations, 2014 CFR

...2014-07-01 2014-07-01 false Detaining an aircraft. 855.15 Section 855.15 National Defense...Defense (Continued) DEPARTMENT OF THE AIR FORCE AIRCRAFT CIVIL AIRCRAFT USE OF UNITED STATES AIR FORCE AIRFIELDS...

2014-07-01

438

FM 3-04.513 Aircraft Recovery Operations  

E-print Network

FM 3-04.513 Aircraft Recovery Operations July 2008 DISTRIBUTION RESTRICTION: Approved for public-04.513 Headquarters Department of the Army Washington, DC, 21 July 2008 Aircraft Recovery Operations Contents Page.............................................................................................. 1-1 Aircraft Recovery

US Army Corps of Engineers

439

77 FR 72250 - Airworthiness Directives; Cessna Aircraft Company Airplanes  

Federal Register 2010, 2011, 2012, 2013, 2014

...2120-AA64 Airworthiness Directives; Cessna Aircraft Company Airplanes AGENCY: Federal Aviation...airworthiness directive (AD) for certain Cessna Aircraft Company Models 172R and 172S airplanes...in this proposed AD, contact Cessna Aircraft Company, Customer service,...

2012-12-05

440

78 FR 67011 - Airworthiness Directives; PILATUS Aircraft Ltd. Airplanes  

Federal Register 2010, 2011, 2012, 2013, 2014

...2120-AA64 Airworthiness Directives; PILATUS Aircraft Ltd. Airplanes AGENCY: Federal Aviation...directive (AD) for certain PILATUS Aircraft Ltd. Model PC-7 airplanes. This AD...identified in this AD, contact PILATUS AIRCRAFT LTD., Customer Technical...

2013-11-08

441

78 FR 28125 - Airworthiness Directives; Twin Commander Aircraft LLC Airplanes  

Federal Register 2010, 2011, 2012, 2013, 2014

...Airworthiness Directives; Twin Commander Aircraft LLC Airplanes AGENCY: Federal Aviation...directive (AD) for certain Twin Commander Aircraft LLC Models 690, 690A, and 690B airplanes...identified in this AD, contact Twin Commander Aircraft LLC; 1176 Telecom Drive,...

2013-05-14

442

77 FR 64442 - Airworthiness Directives; PILATUS AIRCRAFT LTD. Airplanes  

Federal Register 2010, 2011, 2012, 2013, 2014

...2120-AA64 Airworthiness Directives; PILATUS AIRCRAFT LTD. Airplanes AGENCY: Federal Aviation...revising an earlier NPRM for all PILATUS AIRCRAFT LTD. Models PC-12, PC-12/45...in this proposed AD, contact PILATUS AIRCRAFT LTD., Customer Service Manager,...

2012-10-22

443

32 CFR 855.15 - Detaining an aircraft.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Detaining an aircraft. 855.15 Section 855.15 National Defense...Defense (Continued) DEPARTMENT OF THE AIR FORCE AIRCRAFT CIVIL AIRCRAFT USE OF UNITED STATES AIR FORCE AIRFIELDS...

2011-07-01

444

19 CFR 122.41 - Aircraft required to enter.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Aircraft required to enter. 122.41 Section...TREASURY AIR COMMERCE REGULATIONS Aircraft Entry and Entry Documents; Electronic...Non-Crew Members Onboard Commercial Aircraft Arriving In, Continuing Within,...

2012-04-01

445

14 CFR 121.153 - Aircraft requirements: General.  

Code of Federal Regulations, 2012 CFR

... 2012-01-01 2012-01-01 false Aircraft requirements: General. 121.153 Section...DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Aircraft Requirements § 121.153 Aircraft requirements: General. (a) Except...

2012-01-01

446

77 FR 50054 - Airworthiness Directives; Cessna Aircraft Company Airplanes  

Federal Register 2010, 2011, 2012, 2013, 2014

...2120-AA64 Airworthiness Directives; Cessna Aircraft Company Airplanes AGENCY: Federal Aviation...airworthiness directive (AD) for certain Cessna Aircraft Company Models 172R and 172S airplanes...in this proposed AD, contact Cessna Aircraft Company, Customer service,...

2012-08-20

447

14 CFR 121.153 - Aircraft requirements: General.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 2010-01-01 false Aircraft requirements: General. 121.153 Section...DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Aircraft Requirements § 121.153 Aircraft requirements: General. (a) Except...

2010-01-01

448

76 FR 53308 - Airworthiness Directives; Cessna Aircraft Company Airplanes  

Federal Register 2010, 2011, 2012, 2013, 2014

...2120-AA64 Airworthiness Directives; Cessna Aircraft Company Airplanes AGENCY: Federal Aviation...airworthiness directive (AD) for certain Cessna Aircraft Company (Cessna) Models 150F, 150G...identified in this AD, contact Cessna Aircraft Company, Product Support,...

2011-08-26

449

32 CFR 855.15 - Detaining an aircraft.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Detaining an aircraft. 855.15 Section 855.15 National Defense...Defense (Continued) DEPARTMENT OF THE AIR FORCE AIRCRAFT CIVIL AIRCRAFT USE OF UNITED STATES AIR FORCE AIRFIELDS...

2013-07-01

450

14 CFR 121.153 - Aircraft requirements: General.  

Code of Federal Regulations, 2014 CFR

... 2014-01-01 2014-01-01 false Aircraft requirements: General. 121.153 Section...DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Aircraft Requirements § 121.153 Aircraft requirements: General. (a) Except...

2014-01-01

451

Aircraft type influence on contrail properties  

NASA Astrophysics Data System (ADS)

The investigation of the impact of aircraft parameters on contrail properties helps to better understand the climate impact from aviation. Yet, in observations, it is a challenge to separate aircraft and meteorological influences on contrail formation. During the CONCERT campaign in November 2008, contrails from 3 Airbus passenger aircraft of type A319-111, A340-311 and A380-841 were probed at cruise under similar meteorological conditions with in-situ instruments on board the DLR research aircraft Falcon. Within the 2 min old contrails detected near ice saturation, we find similar effective diameters Deff (5.2-5.9 ?m), but differences in particle number densities nice (162-235 cm-3) and in vertical contrail extensions (120-290 m), resulting in large differences in contrail optical depths ? (0.25-0.94). Hence larger aircraft produce optically thicker contrails. Based on the observations, we apply the EULAG-LCM model with explicit ice microphysics and in addition the Contrail and Cirrus Prediction model CoCiP to calculate the aircraft type impact on young contrails under identical meteorological conditions. The observed increase in ? for heavier aircraft is confirmed by the models, yet for generally smaller ?. An aircraft dependence of climate relevant contrail properties persists during contrail lifetime, adding importance to aircraft dependent model initialization. We finally derive an analytical relationship between contrail, aircraft and meteorological parameters. Near ice saturation, contrail width × ? scales linearly with fuel flow rate as confirmed by observations. For higher saturation ratios approximations from theory suggest a non-linear increase in the form (RHI-1)2/3. Summarized our combined results could help to more accurately assess the climate impact from aviation using an aircraft dependent contrail parameterization.

Jeßberger, P.; Voigt, C.; Schumann, U.; Sölch, I.; Schlager, H.; Kaufmann, S.; Petzold, A.; Schäuble, D.; Gayet, J.-F.

2013-05-01

452

Aircraft type influence on contrail properties  

NASA Astrophysics Data System (ADS)

The investigation of the impact of aircraft parameters on contrail properties helps to better understand the climate impact from aviation. Yet, in observations, it is a challenge to separate aircraft and meteorological influences on contrail formation. During the CONCERT campaign in November 2008, contrails from 3 Airbus passenger aircraft of types A319-111, A340-311 and A380-841 were probed at cruise under similar meteorological conditions with in situ instruments on board DLR research aircraft Falcon. Within the 2 min-old contrails detected near ice saturation, we find similar effective diameters Deff (5.2-5.9 ?m), but differences in particle number densities nice (162-235 cm-3) and in vertical contrail extensions (120-290 m), resulting in large differences in contrail optical depths ? at 550 nm (0.25-0.94). Hence larger aircraft produce optically thicker contrails. Based on the observations, we apply the EULAG-LCM model with explicit ice microphysics and, in addition, the Contrail and Cirrus Prediction (CoCiP) model to calculate the aircraft type impact on young contrails under identical meteorological conditions. The observed increase in ? for heavier aircraft is confirmed by the models, yet for generally smaller ?. CoCiP model results suggest that the aircraft dependence of climate-relevant contrail properties persists during contrail lifetime, adding importance to aircraft-dependent model initialization. We finally derive an analytical relationship between contrail, aircraft and meteorological parameters. Near ice saturation, contrail width × ? scales linearly with the fuel flow rate, as confirmed by observations. For higher relative humidity with respect to ice (RHI), the analytical relationship suggests a non-linear increase in the form (RHI-12/3. Summarized, our combined results could help to more accurately assess the climate impact from aviation using an aircraft-dependent contrail parameterization.

Jeßberger, P.; Voigt, C.; Schumann, U.; Sölch, I.; Schlager, H.; Kaufmann, S.; Petzold, A.; Schäuble, D.; Gayet, J.-F.

2013-12-01

453

V/STOL tilt rotor aircraft study. Volume 5: Definition of stowed rotor research aircraft  

NASA Technical Reports Server (NTRS)

The results of a study of folding tilt rotor (stowed rotor) aircraft are presented. The effects of design cruise speed on the gross weight of a conceptual design stowed rotor aircraft are shown and a comparison is made with a conventional (non-folding) tilt rotor aircraft. A flight research stowed rotor design is presented. The program plans, including costs and schedules, are shown for the research aircraft development and a wind tunnel plan is presented for a full scale test of the aircraft.

Soule, V. A.

1973-01-01

454

Improved multiImproved multiaircraft ground aircraft ground Improved multiImproved multi aircraft ground aircraft ground trajectory prediction through wind trajectory prediction through wind  

E-print Network

Improved multiImproved multiaircraft ground aircraft ground Improved multiImproved multi aircraft ground aircraft ground trajectory prediction through wind trajectory prediction through wind forecast support RadioRadar 10/03/2010 5 Aircraft Pilot #12;OnOnline line secisionsecision support toolssupport

Baehr, Christophe

455

Aircraft Loss of Control Study  

NASA Technical Reports Server (NTRS)

Loss of control has become the leading cause of jet fatalities worldwide. Aside from their frequency of occurrence, accidents resulting from loss of aircraft control seize the public s attention by yielding large numbers of fatalities in a single event. In response to the rising threat to aviation safety, NASA's Aviation Safety Program has conducted a study of the loss of control problem. This study gathered four types of information pertaining to loss of control accidents: (1) statistical data; (2) individual accident reports that cite loss of control as a contributing factor; (3) previous meta-analyses of loss of control accidents; and (4) inputs solicited from aircraft manufacturers, air carriers, researchers, and other industry stakeholders. Using these information resources, the study team identified causal factors that were cited in the greatest number of loss of control accidents, and which were emphasized most by industry stakeholders. For each causal factor that was linked to loss of control, the team solicited ideas about what solutions are required and future research efforts that could potentially help avoid their occurrence or mitigate their consequences when they occurred in flight.

Jacobson, Steven R.

2010-01-01

456

Unmanned aircraft systems as wingmen  

NASA Astrophysics Data System (ADS)

This paper introduces a concept towards integrating manned and Unmanned Aircraft Systems (UASs) into a highly functional team though the design and implementation of 3-D distributed formation/flight control algorithms with the goal to act as wingmen for a manned aircraft. This method is designed to minimize user input for team control, dynamically modify formations as required, utilize standard operating formations to reduce pilot resistance to integration, and support splinter groups for surveillance and/or as safeguards between potential threats and manned vehicles. The proposed work coordinates UAS members by utilizing artificial potential functions whose values are based on the state of the unmanned and manned assets including the desired formation, obstacles, task assignments, and perceived intentions. The overall unmanned team geometry is controlled using weighted potential fields. Individual UAS utilize fuzzy logic controllers for stability and navigation as well as a fuzzy reasoning engine for flight path intention prediction. Approaches are demonstrated in simulation using the commercial simulator X-Plane and controllers designed in Matlab/Simulink. Experiments include trail and right echelon formations as well as splinter group surveillance.

Garcia, Richard; Barnes, Laura; Fields, MaryAnne

2010-04-01

457

Commercial-Aircraft Protection System  

NASA Astrophysics Data System (ADS)

Recent world events have identified needs for a commercial aircraft defense system against Man-Portable Air Defense Systems (MANPADS), such as SA-7 and Stinger shoulder launched surface-to-air missiles. Technical challenges include target detection, identification and countermeasures. Political and societal challenges include cost, time to deployment, ground and air safety, and reliability. These challenges, as well as many others, have been met and overcome with the development of Thor Systems' Commercial-Aircraft Protection System (C-APS). C-APS makes use of commercial technology such as radar and infrared sensors with a laser-based countermeasure. Unlike adapted military systems, C-APS detects the threat long before the military versions by employing a 360 degree hemispherical scan, identifying the threat with an infrared sensor and employing a directed laser to not only deflect the target but to permanently disable its seeker. Enhanced capabilities include multiple threat elimination and closed-loop technology for kill verification. All of this is accomplished with development costs less than half that required to convert military technology, manufacturing costs significantly less than competitive products, and a maintenance cycle coincident with standard FAA requirements, which are significantly longer than current systems.

Case, Russell L., Jr.; Wolff, Peter H.

2004-09-01

458

The Sonic Altimeter for Aircraft  

NASA Technical Reports Server (NTRS)

Discussed here are results already achieved with sonic altimeters in light of the theoretical possibilities of such instruments. From the information gained in this investigation, a procedure is outlined to determine whether or not a further development program is justified by the value of the sonic altimeter as an aircraft instrument. The information available in the literature is reviewed and condensed into a summary of sonic altimeter developments. Various methods of receiving the echo and timing the interval between the signal and the echo are considered. A theoretical discussion is given of sonic altimeter errors due to uncertainties in timing, variations in sound velocity, aircraft speed, location of the sending and receiving units, and inclinations of the flight path with respect to the ground surface. Plots are included which summarize the results in each case. An analysis is given of the effect of an inclined flight path on the frequency of the echo. A brief study of the acoustical phases of the sonic altimeter problem is carried through. The results of this analysis are used to predict approximately the maximum operating altitudes of a reasonably designed sonic altimeter under very good and very bad conditions. A final comparison is made between the estimated and experimental maximum operating altitudes which shows good agreement where quantitative information is available.

Draper, C S

1937-01-01

459

Subsonic Ultra Green Aircraft Research  

NASA Technical Reports Server (NTRS)

This Final Report summarizes the work accomplished by the Boeing Subsonic Ultra Green Aircraft Research (SUGAR) team in Phase 1, which includes the time period of October 2008 through March 2010. The team consisted of Boeing Research and Technology, Boeing Commercial Airplanes, General Electric, and Georgia Tech. The team completed the development of a comprehensive future scenario for world-wide commercial aviation, selected baseline and advanced configurations for detailed study, generated technology suites for each configuration, conducted detailed performance analysis, calculated noise and emissions, assessed technology risks, and developed technology roadmaps. Five concepts were evaluated in detail: 2008 baseline, N+3 reference, N+3 high span strut braced wing, N+3 gas turbine battery electric concept, and N+3 hybrid wing body. A wide portfolio of technologies was identified to address the NASA N+3 goals. Significant improvements in air traffic management, aerodynamics, materials and structures, aircraft systems, propulsion, and acoustics are needed. Recommendations for Phase 2 concept and technology projects have been identified.

Bradley, Marty K.; Droney, Christopher K.

2011-01-01

460

41 CFR 102-33.415 - When may we declassify an aircraft and remove it from our Federal aircraft inventory?  

Code of Federal Regulations, 2014 CFR

...2014-01-01 false When may we declassify an aircraft and remove it from our Federal aircraft inventory? 102-33.415 Section 102-33...PERSONAL PROPERTY 33-MANAGEMENT OF GOVERNMENT AIRCRAFT Reporting Information on Government...

2014-01-01

461

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

Code of Federal Regulations, 2013 CFR

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

2013-04-01

462

41 CFR 102-33.415 - When may we declassify an aircraft and remove it from our Federal aircraft inventory?  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false When may we declassify an aircraft and remove it from our Federal aircraft inventory? 102-33.415 Section 102-33...PERSONAL PROPERTY 33-MANAGEMENT OF GOVERNMENT AIRCRAFT Reporting Information on Government...

2013-07-01

463

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

Code of Federal Regulations, 2012 CFR

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

2012-04-01

464

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

Code of Federal Regulations, 2011 CFR

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

2011-04-01

465

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

Code of Federal Regulations, 2010 CFR

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

2010-04-01

466

41 CFR 102-33.415 - When may we declassify an aircraft and remove it from our Federal aircraft inventory?  

Code of Federal Regulations, 2012 CFR

...2012-01-01 false When may we declassify an aircraft and remove it from our Federal aircraft inventory? 102-33.415 Section 102-33...PERSONAL PROPERTY 33-MANAGEMENT OF GOVERNMENT AIRCRAFT Reporting Information on Government...

2012-01-01

467

Hands free data collection for aircraft maintainers  

Microsoft Academic Search

Todaypsilas high demand on our military aircraft and the corresponding lean maintenance workforce requires this lean workforce to focus their attention on repairing mission incapable aircraft, leaving little time to document their actions. When performing maintenance, technicians manage many resources, including team coordination requirements, various tools required for the job, technical order (TO) manuals, and various maintenance documentation systems. Many

Troy Grissom; Rob Done

2008-01-01

468

Aircraft health management network: A user interface  

Microsoft Academic Search

Network management is one of the most discussed topics in the networking fraternity. The efficiency of the network management suit is measured by the number of parameters\\/components handled by the application while making decisions. In the case of Internet-enabled aircrafts, along with network security, even aircraft safety needs to be considered as a factor while designing the network management suit.

N. Thanthry; R. Pendse

2009-01-01

469

Smart Icing Systems for Aircraft Icing Safety  

Microsoft Academic Search

Ice accretion affects the performance and control of an aircraft and in extreme situations can lead to incidents and accidents. However, changes in performance and control are difficult to sense. As a result, the icing sensors currently in use sense primarily ice accretion, not the effect of the ice. No processed aircraft performance degradation information is available to the pilot.

Michael B. Bragg; Tamer Basar; William R. Perkins; Michael S. Selig

2002-01-01

470

Market Forces and Commercial Aircraft Safety  

Microsoft Academic Search

This paper investigates the wealth impact on aircraft manufacturers of crashes involving their aircraft. The author attempts to separate out the regulatory, tort law, and endogenous market components of these costs using stock market data. The results indicate that on average the manufacturer suffers a wealth loss of $21.3 million as the result of a fatal crash in which the

Andrew J Chalk

1987-01-01

471

Unmanned Aircraft and the Human Element: Public  

E-print Network

1 June 2013 Unmanned Aircraft and the Human Element: Public Perceptions and First Responder Kaydos-Daniels, RTI International Introduction Unmanned Aircraft Systems (UAS) are a relatively mature for transition to public safety, first responder, and commercial applications in the United States. Although

McShea, Daniel W.

472

Aircraft accidents.method of analysis  

NASA Technical Reports Server (NTRS)

This report is a revision of NACA-TR-357. It was prepared by the Committee on Aircraft Accidents. The purpose of this report is to provide a basis for the classification and comparison of aircraft accidents, both civil and military.

1937-01-01

473

Autolanding of Commercial Aircrafts by Genetic Programming  

E-print Network

as autolander. The autolander relies on the Instrument Landing System (ILS) which is airport based. The ILS to be satisfied [9]. Most commercial aircrafts are equipped with an auto- matic landing system (ALS), also known and future research. 2 The Autolanding Problem The safe landing of an aircraft requires the control

Fernandez, Thomas

474

Wireless Network Simulation in Aircraft Cabins  

NASA Technical Reports Server (NTRS)

An electromagnetic propagation prediction tool was used to predict electromagnetic field strength inside airplane cabins. A commercial software package, Wireless Insite, was used to predict power levels inside aircraft cabins and the data was compared with previously collected experimental data. It was concluded that the software could qualitatively predict electromagnetic propagation inside the aircraft cabin environment.

Beggs, John H.; Youssef, Mennatoallah; Vahala, Linda

2004-01-01

475

Aircraft battle damage repair - A force multiplier  

Microsoft Academic Search

An aircraft battle-damage repair (BDR) program is described that provides for the assessment and repair of battle damage and the return of badly damaged aircraft to their home bases. The program methodology is based on the use of time-saving temporary repairs and associated training and materials provision. BDR is shown to require knowledge of damage mechanisms and specifications for the

Hess

1992-01-01

476

Lift augmentation for highly swept wing aircraft  

NASA Technical Reports Server (NTRS)

A pair of spaced slots, disposed on each side of an aircraft centerline and spaced well inboard of the wing leading edges, are provided in the wing upper surfaces and directed tangentially spanwise toward thin sharp leading wing edges of a highly swept, delta wing aircraft. The slots are individually connected through separate plenum chambers to separate compressed air tanks and serve, collectively, as a system for providing aircraft lift augmentation. A compressed air supply is tapped from the aircraft turbojet power plant. Suitable valves, under the control of the aircraft pilot, serve to selective provide jet blowing from the individual slots to provide spanwise sheets of jet air closely adjacent to the upper surfaces and across the aircraft wing span to thereby create artificial vortices whose suction generate additional lift on the aircraft. When desired, or found necessary, unequal or one-side wing blowing is employed to generate rolling moments for augmented lateral control. Trailing flaps are provided that may be deflected differentially, individually, or in unison, as needed for assistance in take-off or landing of the aircraft.

Rao, Dhanvada M. (Inventor)

1993-01-01

477

Emerging NDE Technology for aging aircraft  

SciTech Connect

This paper presents an overview of several emerging nondestructive evaluation technologies that are being employed or considered for use to inspect commercial transport, commuter aircraft and military aircraft. An overview of the Federal Aviation Administration (FAA) Airworthiness Assurance NDI Validation Center (AANC) is described and how AANC teams with industry, universities, and other federal entities to assess these technologies.

Moore, D.G.; Perry, R.L.

1998-03-01

478

Alternate-fueled transport aircraft possibilities  

NASA Technical Reports Server (NTRS)

The paper is organized to describe: (1) NASA's cryogenically fueled aircraft program; (2) LH2 subsonic and supersonic transport design possibilities (3) the fuel system and ground side problems associated with LH2 distribution; (4) a comparison of LCH4 with LH2; (5) the design possibilities for LCH4 fueled aircraft; and (6) a summary of where NASA's cryogenically fueled programs are headed.

Aiken, W. S.

1977-01-01

479

Preliminary sizing and performance of aircraft  

NASA Technical Reports Server (NTRS)

The basic processes of a program that performs sizing operations on a baseline aircraft and determines their subsequent effects on aerodynamics, propulsion, weights, and mission performance are described. Input requirements are defined and output listings explained. Results obtained by applying the method to several types of aircraft are discussed.

Fetterman, D. E., Jr.

1985-01-01

480

A review of advanced turboprop transport aircraft  

NASA Astrophysics Data System (ADS)

The application of advanced technologies shows the potential for significant improvement in the fuel efficiency and operating costs of future transport aircraft envisioned for operation in the 1990s time period. One of the more promising advanced technologies is embodied in an advanced turboprop concept originated by Hamilton Standard and NASA and known as the propfan. The propfan concept features a highly loaded multibladed, variable pitch propeller geared to a high pressure ratio gas turbine engine. The blades have high sweepback and advanced airfoil sections to achieve 80 percent propulsive efficiency at M=0.80 cruise speed. Aircraft system studies have shown improvements in fuel efficiency of 15-20 percent for propfan advanced transport aircraft as compared to equivalent turbofan transports. Beginning with the Lockheed C-130 and Electra turboprop aircraft, this paper presents an overview of the evolution of propfan aircraft design concepts and system studies. These system studies include possible civil and military transport applications and data on the performance, community and far-field noise characteristics and operating costs of propfan aircraft design concepts. NASA Aircraft Energy Efficiency (ACEE) program propfan projects with industry are reviewed with respect to system studies of propfan aircraft and recommended flight development programs.

Lange, Roy H.

481

Computer programs for estimating civil aircraft economics  

NASA Technical Reports Server (NTRS)

Computer programs for calculating airline direct operating cost, indirect operating cost, and return on investment were developed to provide a means for determining commercial aircraft life cycle cost and economic performance. A representative wide body subsonic jet aircraft was evaluated to illustrate use of the programs.

Maddalon, D. V.; Molloy, J. K.; Neubawer, M. J.

1980-01-01

482

Aircraft measurements and coordination in FASINEX  

Microsoft Academic Search

As of July 10, 1985, the following progress was made on the proposal work: (1) wind and turbulence measurements on NRL Navy RP3A aircraft, BUNO 149670: (a) Radome pressure transducers purchased and installed with radome tubing, and wiring, test flights were performed to determine if pressure signals are active, (b) data system for aircraft tested, borrowed from National Center for

C. Friehe

1985-01-01

483

Improved Wind Measurements on Research Aircraft  

Microsoft Academic Search

Improved techniques for measuring horizontal and vertical wind components and state variables on research aircraft are presented. They include a filtering method for correcting ground speed and position Inertial Navigation System data with Global Positioning System data, use of moist-air thermodynamic properties in the true airspeed calculation, postflight calculation of the aircraft vertical velocity, and calibration of airflow attack and

D. Khelif; S. P. Burns; C. A. Friehe

1999-01-01

484

Phased array aircraft antennas for satellite communications  

Microsoft Academic Search

A number of critical issues facing designers of aircraft antenna terminals for satellite communication are considered, taking into account a number of efforts aimed at the development of high gain, flush mounted phased array antennas which would eliminate the need for a cumbersome radome. An investigation is conducted regarding the geometrical requirements of a pencil beam aircraft antenna for satellite

R. J. Mailloux

1977-01-01

485

Special problems associated with aircraft radomes  

Microsoft Academic Search

The paper discusses the design and manufacturing aspects of nose radomes for high-speed aircraft. Aircraft radomes are an acceptable comprise of the conflict between the electrical, structural, environmental and aerodynamic requirements. The paper reviews the requirements placed on the design and summarizes the basic radome design and construction methods, as applied in current radome technology, concluding with an examination of

D. A. Conti

1981-01-01

486

Collection and Analysis of Aircraft Emitted Particles  

NASA Technical Reports Server (NTRS)

The University of Denver Aerosol Group proposed to adapt an impactor system for the collection of particles emitted by aircraft. The collection substrates were electron microscope grids which were analyzed by Dr. Pat Sheridan using a transmission electron microscope. The impactor was flown in the SNIFF behind aircraft and engine emissions were sampled. This report details the results of that work.

Wilson, James Charles

1999-01-01

487

The M-15-aircraft (samolot M-15)  

NASA Technical Reports Server (NTRS)

The M-15 is an all-metal, semimonocoque, twin-tail-boom sesquiplane aircraft designed exclusively for agricultural support operations involving slow low-level flight. It is powered by a single Al-25 bypass turbojet engine used in the Yak-40 aircraft. Tanks for spraying chemicals are mounted between the lower and upper wings. Dimensions, weights, and performance data are tabulated.

Leiiecki, R.

1978-01-01

488

Aircraft Manufacturing Occupations. Aviation Careers Series.  

ERIC Educational Resources Information Center

This booklet, one in a series on aviation careers, outlines the variety of careers available in the aircraft manufacturing industry. The first part of the booklet provides general information about careers in the aerospace industry (of which aircraft manufacturing is one part), including the numbers of various types of workers employed in those…

Zaharevitz, Walter

489

Composite aircraft structure having lightning protection  

NASA Technical Reports Server (NTRS)

A lightning protection system for advanced composite aircraft structures consisting of a sandwich structure including two layers of aluminum foil separated by a layer of dielectric material. The sandwich structure is applied to the surface of the composite aircraft structure desired to be protected from lightning strike damage thereby confining damage to the sandwich structure which can be removed and replaced.

Olson, Glenn O. (Inventor)

1982-01-01

490

The multi-stop aircraft routing problem  

E-print Network

We study the multi-stop aircraft routing problem, determining the sequence of stops and the number of passengers to carry in each segment route. The objective of the aircraft routing problem is to maximize the profit derived from the transportation...

Garci?a Castan?eda, Salvador

2012-06-07

491

Carbon fiber reinforced plastics in aircraft construction  

Microsoft Academic Search

Fibrous composites have found applications in aircraft from the first flight of the Wright Brothers’ Flyer 1, in North Carolina on December 17th, 1903, to the plethora of uses now enjoyed by them on both military and civil aircraft, in addition to more exotic applications on unmanned aerial vehicles, space launchers, and satellites. Their growing use has arisen from their

C. Soutis

2005-01-01

492

VIEW OF SOUTHEASTERN INTERIOR SPACE, FACING NORTHWEST. Douglas Aircraft ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

VIEW OF SOUTHEASTERN INTERIOR SPACE, FACING NORTHWEST. - Douglas Aircraft Company Long Beach Plant, Aircraft Parts Shipping & Receiving Building, 3855 Lakewood Boulevard, Long Beach, Los Angeles County, CA

493

VIEW OF CENTRAL INTERIOR SPACE, FACING NORTHEAST. Douglas Aircraft ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

VIEW OF CENTRAL INTERIOR SPACE, FACING NORTHEAST. - Douglas Aircraft Company Long Beach Plant, Aircraft Parts Shipping & Receiving Building, 3855 Lakewood Boulevard, Long Beach, Los Angeles County, CA

494

NASA progress in aircraft noise prediction  

NASA Technical Reports Server (NTRS)

Langley Research Center efforts to develop a methodology for predicting the effective perceived noise level (EPNL) produced by jet-powered CTOL aircraft to an accuracy of + or - 1.5 dB are summarized with emphasis on the aircraft noise prediction program (ANOPP) which contains a complete set of prediction methods for CTOL aircraft including propulsion system noise sources, aerodynamic or airframe noise sources, forward speed effects, a layered atmospheric model with molecular absorption, ground impedance effects including excess ground attenuation, and a received noise contouring capability. The present state of ANOPP is described and its accuracy and applicability to the preliminary aircraft design process is assessed. Areas are indicated where further theoretical and experimental research on noise prediction are needed. Topics covered include the elements of the noise prediction problem which are incorporated in ANOPP, results of comparisons of ANOPP calculations with measured noise levels, and progress toward treating noise as a design constraint in aircraft system studies.

Raney, J. P.; Padula, S. L.; Zorumski, W. E.

1981-01-01

495

Aircraft system modeling error and control error  

NASA Technical Reports Server (NTRS)

A method for modeling error-driven adaptive control of an aircraft. Normal aircraft plant dynamics is modeled, using an original plant description in which a controller responds to a tracking error e(k) to drive the component to a normal reference value according to an asymptote curve. Where the system senses that (1) at least one aircraft plant component is experiencing an excursion and (2) the return of this component value toward its reference value is not proceeding according to the expected controller characteristics, neural network (NN) modeling of aircraft plant operation may be changed. However, if (1) is satisfied but the error component is returning toward its reference value according to expected controller characteristics, the NN will continue to model operation of the aircraft plant according to an original description.

Kulkarni, Nilesh V. (Inventor); Kaneshige, John T. (Inventor); Krishnakumar, Kalmanje S. (Inventor); Burken, John J. (Inventor)

2012-01-01

496

NASA technical advances in aircraft occupant safety  

NASA Technical Reports Server (NTRS)

A NASA program to improve aircraft safety is discussed in terms of three areas of concentration: unexpected turbulence encounters, fire, and crash impact. To provide warning of clear air turbulence (CAT) so that the pilot can take evasive action, a laser Doppler system is described, which functions by measuring backscatter frequency radiation occurring in aerosols ahead of the aircraft. The system was found able to detect CAT, but at shorter than optimal ranges (10 km as opposed to 32 km). Fire safety has focused on both the early detection of fires through improved sensing methods, and on the development of fire-retardant materials, i.e., intumescent char-forming protective coatings. Crashworthiness is discussed in terms of the development of a survivable crash envelope and improved seat and restraint systems. To evaluate an aircraft for crashworthiness, finite-element computer programs are currently being developed which analyze both aircraft structural configurations and the intrinsic strength of aircraft materials.

Enders, J. H.

1978-01-01

497

The design of sport and touring aircraft  

NASA Technical Reports Server (NTRS)

General considerations concerning the design of a new aircraft are discussed, taking into account the objective to develop an aircraft can satisfy economically a certain spectrum of tasks. Requirements related to the design of sport and touring aircraft included in the past mainly a high cruising speed and short take-off and landing runs. Additional requirements for new aircraft are now low fuel consumption and optimal efficiency. A computer program for the computation of flight performance makes it possible to vary automatically a number of parameters, such as flight altitude, wing area, and wing span. The appropriate design characteristics are to a large extent determined by the selection of the flight altitude. Three different wing profiles are compared. Potential improvements with respect to the performance of the aircraft and its efficiency are related to the use of fiber composites, the employment of better propeller profiles, more efficient engines, and the utilization of suitable instrumentation for optimal flight conduction.

Eppler, R.; Guenther, W.

1984-01-01

498

Coupling Dynamics in Aircraft: A Historical Perspective  

NASA Technical Reports Server (NTRS)

Coupling dynamics can produce either adverse or beneficial stability and controllability, depending on the characteristics of the aircraft. This report presents archival anecdotes and analyses of coupling problems experienced by the X-series, Century series, and Space Shuttle aircraft. The three catastrophic sequential coupling modes of the X-2 airplane and the two simultaneous unstable modes of the X-15 and Space Shuttle aircraft are discussed. In addition, the most complex of the coupling interactions, inertia roll coupling, is discussed for the X-2, X-3, F-100A, and YF-102 aircraft. The mechanics of gyroscopics, centrifugal effect, and resonance in coupling dynamics are described. The coupling modes discussed are interacting multiple degrees of freedom of inertial and aerodynamic forces and moments. The aircraft are assumed to be rigid bodies. Structural couplings are not addressed. Various solutions for coupling instabilities are discussed.

Day, Richard E.

1997-01-01

499

NASA Wake Vortex Research for Aircraft Spacing  

NASA Technical Reports Server (NTRS)

The National Aeronautics and Space Administration (NASA) is addressing airport capacity enhancements during instrument meteorological conditions through the Terminal Area Productivity (TAP) program. Within TAP, the Reduced Spacing Operations (RSO) subelement at the NASA Langley Research Center is developing an Aircraft Vortex Spacing System (AVOSS). AVOSS will integrate the output of several inter-related areas to produce weather dependent, dynamic wake vortex spacing criteria. These areas include current and predicted weather conditions, models of wake vortex transport and decay in these weather conditions, real-time feedback of wake vortex behavior from sensors, and operationally acceptable aircraft/wake interaction criteria. In today's ATC system, the AVOSS could inform ATC controllers when a fixed reduced separation becomes safe to apply to large and heavy aircraft categories. With appropriate integration into the Center/TRACON Automation System (CTAS), AVOSS dynamic spacing could be tailored to actual generator/follower aircraft pairs rather than a few broad aircraft categories.

Perry, R. Brad; Hinton, David A.; Stuever, Robert A.

1996-01-01

500

Adaptive control robustness in flexible aircraft application  

NASA Technical Reports Server (NTRS)

This paper presents the application of a model reference adaptive control (MRAC) algorithm to flexible aircraft flight control. The algorithm is an adaptive version of the Command Generator Tracking (CGT) control technique. This technique forces a dynamic system to follow a reduced-order model, allowing it to cope with the problem of unmodeled dynamics. The studies were made via simulation, using for the plant an aircraft dynamic model similar to the B1 bomber. This model is of a large aircraft with a reasonable amount of structural flexibility. In particular, flight configurations were analyzed where the influence of the flexible modes make it difficult to control the aircraft. The results indicate that the algorithm has good robustness properties vis-a-vis unmodeled dynamics and can force the flexible aircraft to follow rigid body responses.

Sanchez, E. N.

1986-01-01