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1

Global Con guration Stabilization for the VTOL Aircraft with Strong Input Coupling  

E-print Network

In this section, we present our control design method for con guration stabilization of the VTOL aircraft. HereGlobal Con guration Stabilization for the VTOL Aircraft with Strong Input Coupling Reza Olfati Trajectory tracking and con guration stabilization for the VTOL aircraft (vertical take o and landing

Sontag, Eduardo

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

Multivariable control of VTOL aircraft for shipboard landing  

NASA Technical Reports Server (NTRS)

The problem of the automatic landing of VTOL aircraft on small ships is considered. Linear quadratic optimal control theory is used to design a VTOL ship motion tracking controller. Optimal root-loci and step responses are obtained to study the dynamics of the closed-loop system. Standard deviations of the ship motion tracking errors, and of the VTOL control amplitudes are computed, illustrating the tradeoff between accurate tracking, and limited control authority. Multivariable robustness margins are also obtained. The tracking of the vertical motion presents the difficulty of requiring large variations of the VTOL total thrust, a control which is limited both in amplitude and in bandwidth. Lateral controls are less restricted, but the motions are strongly coupled, with some adverse couplings in the ship motions, and in the aircraft dynamics. The advantage of the LQ control theory is demonstrated however, by its ability to account for these couplings in a robust manner, and, when possible, to use them to limit the control amplitudes.

Bodson, M.; Athans, M.

1985-01-01

4

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

5

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

6

Massiva - MArs Surface Sampling and Imaging Vtol Aircraft  

NASA Astrophysics Data System (ADS)

This paper proposes a future planetary exploring aircraft for the Martian environment, and considers the mission that follows from the benefits of a small vertical takeoff and landing (VTOL) all-electric system; enabling contact sampling at a number of locations on the planets surface. The recent rover missions have shown the increased value which a mobile platform can add to a mission. The 15 kg aircraft will cover several thousand kilometres in its design lifetime of around twenty take-off cycles. This will enable a large amount of surface contact data to be extracted from a variety of locations as well as the non-contact data from the lower atmosphere and imagery during flight.

Fielding, J.; Underwood, C.

7

Spiral approach navigation concepts for VTOL aircraft using a microwave landing system  

NASA Technical Reports Server (NTRS)

Spiral approaches adjacent to the active runways of CTOL airports have been proposed as a means of effectively interfacing CTOL and VTOL landing operations. Assuming an airport equipped with a Microwave Landing System (MLS), a VTOL aircraft following a spiral approach path might, depending on the specific trajectory, pass alternatively in and out of the linear coverage of the MLS and thereby suffer degraded navigation performance. The objective of this study was to employ essentially state-of-the-art aided inertial navigation concepts to explore the expected navigation performance operating in the environment just described. Results show that aided inertial concepts utilizing simple body-mounted inertia systems may be adequate for an instrument landing if the MLS azimuth and Distance Measuring Equipment (DME) signal coverages extend to within a few feet of the ground.

Mcgee, L. A.

1977-01-01

8

Unsteady features of jets in lift and cruise modes for VTOL aircraft  

NASA Technical Reports Server (NTRS)

Experiments were performed to simulate jet plume effects associated with VTOL aircraft in takeoff and cruise modes. A water facility was used to investigate the influence of inclination angle and separation distance on the three-dimensional fountain flowfield generated by two impinging jets operating at a jet Reynolds number of 250,000. Substantial differences in the flow features were observed for different spacings between the jets. Plume effects in cruise mode were simulated by a supersonic unheated jet parallel to a wall. Variation of the distance between the wall and the edge of the plume is shown to have a major controlling effect on the supersonic screech instability.

Kibens, V.; Saripalli, K. R.; Wlezien, R. W.; Kegelman, J. T.

1988-01-01

9

An investigation of scale model testing of VTOL aircraft in hover  

NASA Technical Reports Server (NTRS)

Utilizing the unique opportunity created by full scale hover testing of the twin-jet Grumman Design 698 VTOL aircraft in the NASA-Ames Hover Facility, a series of experiments was conducted to evaluate the effectivness of scale model testing in predicting full scale behavior. Interference forces were found to be sensitive to aircraft lower surface geometry, but when the geometry was modeled accurately the small scale results matched full scale forces guite well. The interference forces were found to be insensitive to core nozzle temperature and fan nozzle pressure ratio. The results clearly demonstrate that small scale models can be reliably utilized for aircraft and technology development when the appropriate sensitivities are recognized.

Hill, W. G., Jr.; Jenkins, R. C.; Dudley, M. R.

1982-01-01

10

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

11

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

12

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

13

Influence of friction forces on the motion of VTOL aircraft during landing operations on ships at sea  

NASA Technical Reports Server (NTRS)

Equations describing the friction forces generated during landing operations on ships at sea were formulated. These forces depend on the platform reaction and the coefficient of friction. The platform reaction depends on the relative sink rate and the shock absorbing capability of the landing gear. The friction coefficient varies with the surface condition of the landing platform and the angle of yaw of the aircraft relative to the landing platform. Landings by VTOL aircraft, equipped with conventional oleopneumatic landing gears are discussed. Simplifications are introduced to reduce the complexity of the mathematical description of the tire and shock strut characteristics. Approximating the actual complicated force deflection characteristic of the tire by linear relationship is adequate. The internal friction forces in the shock strut are included in the landing gear model. A set of relatively simple equations was obtained by including only those tire and shock strut characteristics that contribute significantly to the generation of landing gear forces.

Howard, J. C.; Chin, D. O.

1981-01-01

14

Helicopters and VTOL. I  

NASA Technical Reports Server (NTRS)

Performance projections into the next half-century of VTOL aircraft design are presently made on the basis of recent design trends. Attention is given to the technology-development and commercial prospects for tilt-rotor, thrust-vectoring hover, lighter-than-air, and speculative electromagnetic-propulsion, remotely-beamed power systems. Highly automated air traffic control systems are envisioned which will incorporate AI, satellite positioning, synthetic vision, obstacle detection/avoidance and fiber-optic transmission to safely manage giant airborne mass-transit commuter systems. It is expected that tilt-rotor aircraft will become the dominant VTOL configuration as time passes.

Burks, John S.

1989-01-01

15

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

16

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

17

VTOL aircraft in emergency planning and management: a model for a helipad network.  

PubMed

The scientific literature regarding HEMS (Helicopter Emergency Medical Service) planning lacks a method for defining optimal sites for helipads that takes into account risk distribution and hospital location. Such a method could minimise overall rescue time in emergency situations. In this paper a method that supports the decisions taken by disaster planners and managers is developed, focusing on the quantification of necessary air resources for the management of some probable calamities. Given a region characterised by a natural and non-natural disaster risk map, along with a comprehensive transport system (also characterised by a risk map), a set of emergency destinations (hospitals), a set of heliports/helipads dislocated on the territory and a number of available HEMS rotorcraft, the aim of the paper is to assess the adequacy of the VTOL/FATO (Vertical Take-Off and Landing/Final Take-Off and Landing Area) system in order to deal with a set of possible emergencies. PMID:18498369

Caprì, Salvatore; Ignaccolo, Matteo; Inturri, Giuseppe

2009-03-01

18

Evaluation of a real-time predictive guidance law for landing VTOL aircraft at sea  

NASA Technical Reports Server (NTRS)

A piloted simulation evaluation was conducted to assess the merits of a predictive lull/swell guidance law for landing a vertical takeoff and landing aircraft at sea. Two cases were evaluated. The first was performed by the pilot without the aid of the lull/swell guidance indicator, which indicates a landing opportunity. The second was performed in a similar manner with the aid of the guidance indicator. The pilot was instructed to use the guidance indicator only as a landing aid. The results indicated the pilots were able to visually determine ship lulls and swells prior to landing. However, use of the lull/swell guidance resulted in increased pilot confidence in the existence of a landing opportunity, which resulted in significantly shorter hover waiting times prior to landing. The performance of the lull/swell guidance was conservative, in that it forecast the onset of deck lulls and swells later than the pilot could detect them, but with greater reliability and therefore greater pilot confidence. In no instances did the guidance algorithm predict a false ship lull with which the pilot did not agree.

Paulk, C. H., Jr.; Phatak, A. V.

1984-01-01

19

An investigation into the vertical axis control power requirements for landing VTOL type aircraft onboard nonaviation ships in various sea states  

NASA Technical Reports Server (NTRS)

The problem of determining the vertical axis control requirements for landing a VTOL aircraft on a moving ship deck in various sea states is examined. Both a fixed-base piloted simulation and a nonpiloted simulation were used to determine the landing performance as influenced by thrust-to-weight ratio, vertical damping, and engine lags. The piloted simulation was run using a fixed-based simulator at Ames Research center. Simplified versions of an existing AV-8A Harrier model and an existing head-up display format were used. The ship model used was that of a DD963 class destroyer. Simplified linear models of the pilot, aircraft, ship motion, and ship air-wake turbulence were developed for the nonpiloted simulation. A unique aspect of the nonpiloted simulation was the development of a model of the piloting strategy used for shipboard landing. This model was refined during the piloted simulation until it provided a reasonably good representation of observed pilot behavior.

Stevens, M. E.; Roskam, J.

1985-01-01

20

Conceptual design, evaluation and research identification for Remote Augmented Propulsive Lift Systems (RALS) with ejectors for VTOL aircraft  

NASA Technical Reports Server (NTRS)

Ejector concepts for use with a remote augmented lift system (RALS) exhaust nozzle were studied. A number of concepts were considered and three were selected as having the greatest promise of providing the desired aircraft and exhaust gas cooling and lift enhancement. A scale model test program is recommended to explore the effects of the more important parameters on ejector performance.

Willis, W. S.; Konarski, M.; Sutherland, M. V.

1982-01-01

21

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

22

COTS approach to a utility VTOL UAV  

NASA Astrophysics Data System (ADS)

Many UAVs are in the market place but few are very profitable. After studying the lessons learned form our predecessors, a commercial off the shelf approach was chosen to meet the price performance challenge. A multi-mission capable aircraft was chosen to provide exposure to the widest possible market. Using an analysis tool developed for DARPA, the Vigilante VTOL UAV was successfully competed against both Outrider and Predator.

Snyder, Jay R.

1998-11-01

23

A translational velocity command system for VTOL low speed flight  

NASA Technical Reports Server (NTRS)

A translational velocity flight controller, suitable for very low speed maneuvering, is described and its application to a large class of VTOL aircraft from jet lift to propeller driven types is analyzed. Estimates for the more critical lateral axis lead to the conclusion that the controller would provide a jet lift (high disk loading) VTOL aircraft with satisfactory "hands off" station keeping in operational conditions more stringent than any specified in current or projected requirements. It also seems likely that ducted fan or propeller driven (low disk loading) VTOL aircraft would have acceptable hovering handling qualities even in high turbulence, although in these conditions pilot intervention to maintain satisfactory station keeping would probably be required for landing in restricted areas.

Merrick, V. K.

1982-01-01

24

Modeling and PD Control of a Quadrotor VTOL Vehicle  

Microsoft Academic Search

In this paper, we present a model of a four rotor vertical take-off and landing (VTOL) unmanned air vehicle known as quadrotor aircraft. And we explained its control architecture including vision based control. Quadrotors have generated considerable interest in both the control community due to their complex dynamics and military because of their advantages over regular air vehicles. The proposed

Bora Erginer; E. Altug

2007-01-01

25

How good is jet lift VTOL technology  

NASA Technical Reports Server (NTRS)

The status of technologies for jet-lift V/STOL aircraft is examined, and a critical review of the performance of jet-lift VTOL aircraft built to date is made. Most jet-lift aircraft have suffered from adverse propulsion-induced effects during takeoff and landing. Flight dynamics of jet-lift aircraft have suffered from shortcomings in static and dynamic stability, control characteristics, and flight path control. Some of the main problems to be considered during the selection of a propulsion system arrangement for a V/STOL fighter are discussed. At present, experimental and analytical data on supersonic V/STOL configurations are insufficient to permit evaluating propulsion system arrangements.

Anderson, S. B.; Petersen, R. H.

1977-01-01

26

Ship motion pattern directed VTOL letdown guidance  

NASA Technical Reports Server (NTRS)

This paper examines ship motion pattern directed letdown guidance strategies for landing a VTOL aircraft onboard a small aviation ship under adverse environmental conditions. Off-line computer simulation of the shipboard landing task is utilized for assessing the relative merits of the proposed guidance schemes. A sum of seventy sinusoids representation is used to model the ship motion time histories. The touchdown performance of a nonimal constant-rate-of-descent (CROD) letdown strategy serves as a benchmark for ranking the performance of the alternative letdown schemes.

Phatak, A. V.; Karmali, M. S.; Paulk, C. H., Jr.

1983-01-01

27

Analysis of selected VTOL concepts for a civil transportation mission  

NASA Technical Reports Server (NTRS)

As part of defining the needs and technology requirements for VTOL aircraft research and development, the objective of this paper is to study the application of two tilt propulsion concept VTOL aircraft to the business/executive transport mission. The two concepts selected for study are the tilt jet concept utilizing rotating turbofan engines for both vertical lift and cruise thrust, and the tilt rotor concept using relatively low disc loading propellers for hover and cruise. Overall mission costs, including the time-value cost of the executives, was computed for a selected range of mission distances, up to the design mission range of 750 nm (1400 km). The total trip cost was also compared to that of a conventional helicopter/business jet combination for a typical executive transport mission.

Wilson, S. B., III; Bowles, J. V.; Foster, J. D.

1981-01-01

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

Greenlandair VTOL transportation study  

NASA Technical Reports Server (NTRS)

An operational and economic analysis was conducted on Greenlandair, a large helicopter commuter operation. Results indicate that the airline could realize a significant increase in available seat miles with a decrease in total cost by replacing the fleet of helicopters and fixed-wing aircraft with Tiltrotors. The Tiltrotor can fly 2.5 times faster than the helicopters, and 25% faster than the presently used turboprop aicraft. Fuel consumption could be reduced by one half, and with additional savings on maintenance, crew costs, and ground support costs, plus expanded flight schedules, the airline could achieve a net yearly savings of over 2 million dollars.

Reber, R. R.

1981-01-01

31

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

NASA Technical Reports Server (NTRS)

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

Patton, J. M., Jr.

1972-01-01

32

Applications for mini VTOL UAV for law enforcement  

NASA Astrophysics Data System (ADS)

Remotely operated vehicle systems, ground and air, have great potential for supporting law enforcement operations. These systems with their onboard sensors, can assist in collecting evidence, performing long-term surveillance or in assessing hazardous situations prior to committing personnel. Remote ground vehicles are presently used by many police departments for ordnance clearing missions. Unmanned ground vehicles (UGVs) typically offer long endurance, and are intuitive to operate, but can be severely limited in where they can go by terrain and obstacles. Unmanned air vehicles (UAVs) have 3-D mobility, but have landing and takeoff restrictions, mission time limitations, and typically are demanding to operate. A new capability has been demonstrated for the U.S. military that shows great promise for aiding police agencies. This concept uses a shrouded rotor, vertical take off and landing (VTOL), an unmanned air vehicle to provide mobility to sensors and other payloads. This system can either perform surveillance from the air or travel to a remote location and land to position onboard sensors to perform long-term surveillance from the ground. This mobility platform concept can also be used to position packages (e.g., communications repeaters) or deliver and deploy non-lethal agents. This paper presents the concept of a small, UAV, VTOL, sensor mobility system for support of law enforcement operations. It then discusses operational feasibility and briefly reviews demonstrations of surveillance and sensor placement operations in military urban terrain scenarios performed by the Space and Naval Warfare (SPAWAR) Systems Center San Diego (SSCSD) and Sikorsky Aircraft with their full-size Cypher UAV. We then discuss the practicality of reducing the size of this capability to a system small enough to be transported in standard police vehicles and which can be easily operated by law enforcement personnel.

Murphy, Douglas W.; Cycon, James

1999-01-01

33

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

34

Design of a new VTOL UAV by combining cycloidal blades and FanWing propellers  

NASA Astrophysics Data System (ADS)

Though the propelling principles of Cycloidal Blades and FanWing propellers are totally different, their structures are similar. Therefore, it is possible to develop an aircraft which combines both types of the propulsion modes of Cyclogyro and FanWing aircrafts. For this kind of aircraft, Cycloidal Blades Mode provides capabilities of Vertical Take-Off and Landing, Instantly Alterable Vector Thrusting, and Low Noise. The FanWing Mode provides capabilities of High Efficiency, Energy-Saving, and Cannot-Stall Low-Speed Cruising. Besides, because both of these propellers are observably better than conventional screw propeller in terms of efficiency, so this type of VTOL UAV could fly with Long Endurance. Furthermore, the usage of flying-wing takes advantage of high structure utilization and high aerodynamic efficiency, eliminates the interference of fuselage and tail, and overcomes flying wing's shortcomings of pitching direction instability and difficulty of control. A new magnetic suspension track-type cycloidal propulsion system is also presented in the paper to solve problems of heavy structure, high mechanical resistance, and low reliability in the traditional cycloidal propellers. The further purpose of this design is to trying to make long-endurance VTOL aircraft and Practical Flying Cars possible in reality, and to bring a new era to the aviation industry.

Li, Daizong

35

A flight evaluation of VTOL jet transport under visual and simulated instrument conditions  

NASA Technical Reports Server (NTRS)

A flight investigation was performed with the Dornier DO-31 VTOL to evaluate the performance, handling qualities, and operating characteristics that are considered to be important in the operation of a commerical VTOL transport in the terminal area. The DO-31, a 20,000 kilogram transport, has a mixed jet propulsion system; main engines with nozzles deflect from a cruise to a hover position, and vertical lift engines operated below 170 knots. This VTOL mode incorporates pitch and roll attitude and yaw rate stabilization. The tests concentrated on the transition, approach, and vertical landing. The mixed jet propulsion system provided a large usable performance envelope that enabled simulated IFR approaches to be made on 7 deg and 12 deg glide slopes. In these approaches management of thrust magnitude and direction was a primary problem, and some form of integrating the controls will be necessary. The handling qualities evaluation pointed out the need for additional research of define flight path criteria. The aircraft had satisfactory control and stability in hover out of ground effect. The recirculation effects in vertical landing were large below 15 meters.

Holzhauser, C. A.; Morello, S. A.; Innis, R. C.; Patton, J. M., Jr.

1972-01-01

36

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

37

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

38

Evaluation of the navigation performance of shipboard-VTOL-landing guidance systems  

NASA Technical Reports Server (NTRS)

The objective of this study was to explore the performance of a VTOL aircraft landing approach navigation system that receives data (1) from either a microwave scanning beam (MSB) or a radar-transponder (R-T) landing guidance system, and (2) information data-linked from an aviation facility ship. State-of-the-art low-cost-aided inertial techniques and variable gain filters were used in the assumed navigation system. Compensation for ship motion was accomplished by a landing pad deviation vector concept that is a measure of the landing pad's deviation from its calm sea location. The results show that the landing guidance concepts were successful in meeting all of the current Navy navigation error specifications, provided that vector magnitude of the allowable error, rather than the error in each axis, is a permissible interpretation of acceptable performance. The success of these concepts, however, is strongly dependent on the distance measuring equipment bias. In addition, the 'best possible' closed-loop tracking performance achievable with the assumed point-mass VTOL aircraft guidance concept is demonstrated.

Mcgee, L. A.; Paulk, C. H., Jr.; Steck, S. A.; Schmidt, S. F.; Merz, A. W.

1979-01-01

39

An analysis of a nonlinear instability in the implementation of a VTOL control system  

NASA Technical Reports Server (NTRS)

The contributions to nonlinear behavior and unstable response of the model following yaw control system of a VTOL aircraft during hover were determined. The system was designed as a state rate feedback implicit model follower that provided yaw rate command/heading hold capability and used combined full authority parallel and limited authority series servo actuators to generate an input to the yaw reaction control system of the aircraft. Both linear and nonlinear system models, as well as describing function linearization techniques were used to determine the influence on the control system instability of input magnitude and bandwidth, series servo authority, and system bandwidth. Results of the analysis describe stability boundaries as a function of these system design characteristics.

Weber, J. M.

1982-01-01

40

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

41

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

42

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

43

Navigation systems for approach and landing of VTOL aircraft  

NASA Technical Reports Server (NTRS)

The formulation and implementation of navigation systems used for research investigations in the V/STOLAND avionics system are described. The navigation systems prove position and velocity in a cartestian reference frame aligned with the runway. They use filtering techniques to combine the raw position data from navaids (e.g., TACAN, MLS) with data from onboard inertial sensors. The filtering techniques which use both complementary and Kalman filters, are described. The software for the navigation systems is also described.

Schmidt, S. F.; Mohr, R. L.

1979-01-01

44

A variable structure approach to robust control of VTOL aircraft  

NASA Technical Reports Server (NTRS)

This paper examines the application of variable structure control theory to the design of a flight control system for the AV-8A Harrier in a hover mode. The objective in variable structure design is to confine the motion to a subspace of the total state space. The motion in this subspace is insensitive to system parameter variations and external disturbances that lie in the range space of the control. A switching type of control law results from the design procedure. The control system was designed to track a vector velocity command defined in the body frame. For comparison purposes, a proportional controller was designed using optimal linear regulator theory. Both control designs were first evaluated for transient response performance using a linearized model, then a nonlinear simulation study of a hovering approach to landing was conducted. Wind turbulence was modeled using a 1052 destroyer class air wake model.

Calise, A. J.; Kramer, F.

1982-01-01

45

A variable structure approach to robust control of VTOL aircraft  

NASA Technical Reports Server (NTRS)

This paper examines the application of variable structure control theory to the design of a flight control system for the AV-8A Harrier in a hover mode. The objective in variable structure design is to confine the state trajectories to a subspace of the total state space. The motion in this subspace is insensitive to system parameter variations and external disturbances that lie in the range space of the control. A switching type of control law results from the design procedure. The control system was designed to track a vector-valued velocity command. For comparison, a proportional controller was designed using optimal linear regulator theory. Both controllers were evaluated for their transient response performance using a linear model; then a nonlinear simulation study of a hovering approach to landing was conducted. The variable structure controller outperformed its linear counterpart in the presence of wind disturbances and plant parameter uncertainties afforded by the simulation.

Calise, A. J.; Kramer, F. S.

1984-01-01

46

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

47

Design of a long endurance Titan VTOL vehicle  

Microsoft Academic Search

Saturn's moon Titan promises insight into numerous key scientific questions, many of which can be investigated only by in situ exploration of its surface and atmosphere. This paper presents research on a vertical takeoff and landing (VTOL) vehicle designed to conduct a scientific investigation of Titan's atmosphere, clouds, haze, surface, and any possible oceans. Multiple options for vertical takeoff and

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

2006-01-01

48

Multibody Dynamics Model of a VTOL Teetering Rotor  

Microsoft Academic Search

This paper presents the development of a multibody dynamics model of a VTOL teetering rotor. The developed model includes a teetering hub, containing a flexure and torque tube, rotor blades, pitch links, and swashplate system. A non-teetering rotor configuration, which modified the baseline teetering rotor by removing the teeter- ing hinge, is also developed, and its aeromechanics characteristics compared to

Jinwei Shen; Pierangelo Masarati; Jeremy Bain

2010-01-01

49

Large-eddy simulations of excitation effects on a VTOL upwash fountain  

NASA Astrophysics Data System (ADS)

The responses of an upwash fountain to various azimuthal and axisymmetric excitations, applied at the exits of its neighboring jets, are investigated. Kinematic arguments are used to determine the interactions of large-scale structures in the fountain and the effects of these interactions on the fountain's characteristics. Numerical simulations of a row of impinging jets, which contain the essential features of twin jets impinging on the ground, are used to simulate the hovering configuration of a vertical takeoff and landing (VTOL) aircraft. The flow is assumed to be governed by the time-dependent, incompressible Navier-Stokes equations. The large-eddy simulation approach is followed. Distinct fountain characteristics are shared among the cases in which azimuthal perturbations are applied at both jet exits in the same direction. These include a high fountain spreading rate, a strong lateral interaction with the neighboring jets, and a weak upload at the aircraft's undersurface. A strong similarity in fountain characteristics also exists for the cases of axisymmetric forcing and azimuthal forcing in opposite directions at the two jet exits. The similar characteristics here include a low fountain spreading rate and a strong upload at the aircraft's undersurface.

Rizk, Magdi H.; Menon, Suresh

1989-04-01

50

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

51

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

52

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

53

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

54

Reduction in size and unsteadiness of a VTOL ground vortex by ground fences  

NASA Technical Reports Server (NTRS)

A ground vortex, produced when a jet impinges on the ground in the presence of cross flow, is encountered by V/STOL aircraft hovering near the ground and is known to be hazardous to the aircraft. The objective of this research was to identify a ground-based technique by which both the mean size and fluctuation in size of the ground vortex could be reduced. A simple passive method was identified and examined in the laboratory. Specifically, one or two fine wire mesh screens (ground fences) bent in a horseshoe shape and located on the ground in front of the jet impingement point proved to be very effective. The ground fences work by decreasing the momentum of the upstream-traveling wall jet, effectively causing a higher freestream-to-jet velocity ratio (V(sub infinity)/V(sub j)) and thus, a ground vortex smaller in size and unsteadiness. At(V(sub infinity)/V(sub j)) = 0.15, the addition of a single ground fence resulted in a 70 percent reduction in mean size of the ground vortex. With two ground fences, the mean size decreased by about 85 percent. Fluctuations in size decreased nearly in proportion to the mean size, for both the single and double fence configurations. These results were consistent over a wide range of jet Reynolds number (10(exp 4) less than Re(sub jet) less than 10(exp 5)); further development and full-scale Reynolds number testing are required, however, to determine if this technique can be made practical for the case of actual VTOL aircraft.

Cimbala, John M.; Billet, Michael L.; Harman, Todd B.

1993-01-01

55

Advanced subsonic aircraft concepts for passenger transportation  

NASA Technical Reports Server (NTRS)

This paper discusses the potential for new subsonic transport aircraft designs that may evolve in the relatively near future, taking into account the added requirements for improved environmental compatibility and the potential constraints due to system congestion, substantial financial risk, and higher fuel costs or limited availability. Reflecting these additional requirements, potential aircraft developments are presented for new CTOL transports with significantly improved fuel economy, new STOL transports with improved short field capability, and new VTOL transports that could provide direct city-center service.

Waters, M. H.; Williams, L. J.

1975-01-01

56

Rotary-wing aeroelasticity with application to VTOL vehicles  

NASA Technical Reports Server (NTRS)

A concise assessment is presented of the state of the art in the field of rotary-wing aeroelasticity (RWE). The basic ingredients of RWE are reviewed, including structural modeling, unsteady aerodynamic modeling, formulation of the equations of motion, and solution methods. Results illustrating these methods are presented for isolated blades and coupled rotor-fuselage problems. The application of active controls to suppress aeromechanical and aeroelastic instabilities and to reduce vibration in rotorcraft is discussed. Structural optimization with aeroelastic constraints, gust response analysis of helicopters, and aeroelastic problems in special VTOL vehicles are briefly examined.

Friedmann, Peretz P.

1993-01-01

57

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

58

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

59

Rotary-wing aeroelasticity with application to VTOL vehicles  

NASA Technical Reports Server (NTRS)

This survey presents an assessment of the state of the art in rotary-wing aeroelasticity as applied to conventional helicopters as well as other VTOL vehicles such as tilting prop-rotors, the X-wing and a hybrid heavy lift vehicle. The objective is to enable the reader to develop an awareness of what has been accomplished, what remains to be done, and where to find more comprehensive treatments of the various topics discussed. The main topics discussed are: (1) structural modeling; (2) unsteady aerodynamic modeling; (3) formulation of the equations of motion and their solutions; (4) illustrative results for isolated blades in hover and forward flight; (5) illustrative results for coupled rotor/fuselage problems; (6) active control of aeromechanical and aeroelastic problems; (7) active controls for vibration reduction; (8) structural optimization with aeroelastic constraints; (9) gust response analysis of rotors; and (10) aeroelastic problems in special VTOL vehicles. These topics are reviewed with different levels of detail and some useful observation on potentially rewarding areas of future research are made.

Friedmann, Peretz P.

1990-01-01

60

Fluidic Emergency Thruster for Aircraft  

NASA Technical Reports Server (NTRS)

The design, development, fabrication and test evaluation of two prototype fluidic emergency thrusters (FET) for aircraft stabilization are discussed. The fluidic control units were designed to provide, between two diametrically opposed nozzles, a thrust differential proportional to an input voltage signal. The emergency roll control requirements of the X-14 VTOL research aircraft were defined as typical design goals. Two control units, one on each wing tip, are intended to provide a maximum thrust of 224 pounds per unit. The units are designed to operate with 2500 psig, 2000 F gas from a solid propellant gas generator. The emergency system including the gas generator was designed to add less than 11 pounds per wing tip. The operating time under emergency conditions was specified as five seconds. The fluidic emergency thruster is similar in concept to a JATO system but has the added feature of controllable thrust.

Honda, T. S.

1972-01-01

61

Image based augmentation of an autonomous VTOL-MAV  

NASA Astrophysics Data System (ADS)

In this paper, the development of a vision based system for a small-scale VTOL-MAV is presented. The on-board GPS/INS navigation system is augmented by further sensors in order to allow for an autonomous waypoint mode. Especially in urban environments the GPSsignal quality is disturbed by shading and multipath propagation. The investigated vision system based on algorithms analyzing the optical flow is essential to enable the helicopter to reliably hover even in these scenarios. Due to the integration of the vision based navigation information into the navigation filter, GPSsignal outages can be bridged. The necessary height above ground information is estimated from the relative altitude change given by the barometric altimeter and the optical flow.

Frietsch, N.; Maier, A.; Kessler, C.; Meister, O.; Seibold, J.; Trommer, G. F.

2009-09-01

62

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

NASA Technical Reports Server (NTRS)

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

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

1980-01-01

63

Design and development of an unconventional VTOL micro air vehicle: The Cyclocopter  

NASA Astrophysics Data System (ADS)

This paper discusses the systematic experimental and vehicle design/development studies conducted at the University of Maryland which culminated in the development of the first flying Cyclocopter in the history. Cyclocopter is a novel Vertical Take-Off and Landing (VTOL) aircraft, which utilizes cycloidalrotors (cyclorotors), a revolutionary horizontal axis propulsion concept, that has many advantages such as higher aerodynamic efficiency, maneuverability and high-speed forward flight capability when compared to a conventional helicopter rotor. The experimental studies included a detailed parametric study to understand the effect of rotor geometry and blade kinematics on cyclorotor hover performance. Based on the experimental results, higher blade pitch angles were found to improve thrust and increase the power loading (thrust per unit power) of the cyclorotor. Asymmetric pitching with higher pitch angle at the top than at the bottom produced better power loading. The chordwise optimum pitching axis location was observed to be around 25-35% of the blade chord. Because of the flow curvature effects, the cycloidal rotor performance was a strong function of the chord/radius ratio. The optimum chord/radius ratios were extremely high, around 0.5-0.8, depending on the blade pitching amplitude. A flow field investigation was also conducted using Particle Image Velocimetry (PIV) to unravel the physics behind thrust production of a cyclorotor. PIV studies indicated evidence of a stall delay as well as possible increases in lift on the blades from the presence of a leading edge vortex. The goal of all these studies was to understand and optimize the performance of a micro-scale cyclorotor so that it could be used in a flying vehicle. An optimized cyclorotor was used to develop a 200 gram cyclocopter capable of autonomous stable hover using an onboard feedback controller.

Benedict, Moble; Chopra, Inderjit

2012-06-01

64

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

65

Flight Tests of A 1/8-Scale Model of the Bell D-188A Jet VTOL Airplane  

NASA Technical Reports Server (NTRS)

The Bell D-188A VTOL airplane is a horizontal-attitude VTOL fighter with tilting engine nacelles at the tips of a low-aspect-ratio unswept wing and additional engines in the fuselage. The model could be flown smoothly in hovering and transition flight. In forward flight the model could be flown smoothly at the lower angles of attack but experienced an uncontrollable directional divergence at angles of attack above about 16 deg.

Smith, Charles C., Jr.

1959-01-01

66

Aerocrane: A hybrid LTA aircraft for aerial crane applications  

NASA Technical Reports Server (NTRS)

The Aerocrane, a hybrid aircraft, combines rotor lift with buoyant lift to offer VTOL load capability greatly in excess of helicopter technology while eliminating the airship problem of ballast transfer. In addition, the Aerocrane concept sharply reduces the mooring problem of airships and provides 360 deg vectorable thrust to supply a relatively large force component for control of gust loads. Designed for use in short range, ultra heavy lift missions, the Aerocrane operates in a performance envelope unsuitable for either helicopters or airships. Basic design considerations and potential problem areas of the concept are addressed.

Perkins, R. G., Jr.; Doolittle, D. B.

1975-01-01

67

Rocket-based combined-cycle (RBCC) powered spaceliner class vehicle can advantageously employ vertical takeoff and landing (VTOL)  

NASA Technical Reports Server (NTRS)

The subject is next generation orbital space transporation, taken to be fully reusable non-staged 'aircraft like' systems targeted for routine, affordable access to space. Specifically, the takeoff and landing approach to be selected for such systems is considered, mainly from a propulsion viewpoint. Conventional wisdom has it that any transatmospheric-class vehicle which uses high-speed airbreathing propulsion modes (e.g., scramjet) intrinsically must utilize horizontal takeoff and landing, HTOHL. Although this may be true for all-airbreathing propulsion (i.e., no rocket content as in turboramjet propulsion), that emerging class of powerplant which integrally combines airbreathing and rocket propulsion, referred to as rocket-based combined-cycle (RBCC) propulsion, is considerably more flexible with respect to selecting takeoff/landing modes. In fact, it is proposed that any of the modes of interest may potentially be selected: HTOHL, VTOHL, VTOVL. To illustrate this surmise, the case of a previously documented RBCC-powered 'Spaceliner' class space transport concept, which is designed for vertical takeoff and landing, is examined. The 'RBCC' and 'Spaceliner' categories are first described for background. Departing form an often presumed HTOHL baseline, the leading design and operational advantages of moving to VTOVL are then elucidated. Technical substantiation that the RBCC approach, in fact, enables this capability (but also that of HTOHL and VTOVL) is provided, with extensive reference to case-in-point supporting studies. The paper closes with a set of conditional surmises bearing on its set of conclusions, which point up the operational cost advantages associated with selecting the vertical takeoff and landing mode combination (VTOL), uniquely offered by RBCC propulsion.

Escher, William J. D.

1995-01-01

68

Rocket-based combined-cycle (RBCC) powered spaceliner class vehicle can advantageously employ vertical takeoff and landing (VTOL)  

NASA Astrophysics Data System (ADS)

The subject is next generation orbital space transporation, taken to be fully reusable non-staged 'aircraft like' systems targeted for routine, affordable access to space. Specifically, the takeoff and landing approach to be selected for such systems is considered, mainly from a propulsion viewpoint. Conventional wisdom has it that any transatmospheric-class vehicle which uses high-speed airbreathing propulsion modes (e.g., scramjet) intrinsically must utilize horizontal takeoff and landing, HTOHL. Although this may be true for all-airbreathing propulsion (i.e., no rocket content as in turboramjet propulsion), that emerging class of powerplant which integrally combines airbreathing and rocket propulsion, referred to as rocket-based combined-cycle (RBCC) propulsion, is considerably more flexible with respect to selecting takeoff/landing modes. In fact, it is proposed that any of the modes of interest may potentially be selected: HTOHL, VTOHL, VTOVL. To illustrate this surmise, the case of a previously documented RBCC-powered 'Spaceliner' class space transport concept, which is designed for vertical takeoff and landing, is examined. The 'RBCC' and 'Spaceliner' categories are first described for background. Departing form an often presumed HTOHL baseline, the leading design and operational advantages of moving to VTOVL are then elucidated. Technical substantiation that the RBCC approach, in fact, enables this capability (but also that of HTOHL and VTOVL) is provided, with extensive reference to case-in-point supporting studies. The paper closes with a set of conditional surmises bearing on its set of conclusions, which point up the operational cost advantages associated with selecting the vertical takeoff and landing mode combination (VTOL), uniquely offered by RBCC propulsion.

Escher, William J. D.

69

History of the Phoenix VTOL SSTO and recent developments in single-stage launch systems  

NASA Astrophysics Data System (ADS)

The history of the VTOL SSTO (single stage to orbit) concept and the Phoenix designs is reviewed. The role the Phoenix concept played in stimulating consideration of the SSTO approach by the U.S. Government in ongoing SSTO concept studies is also discussed. It is pointed out that these studies are currently expected to lead to prototype hardware development aimed at demonstrating the SSTO approach by 1995-1997 in the form of the McDonnell-Douglas DC-Y.

Hudson, Gary C.

70

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

71

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

72

A practical receding horizon control framework for path planning and control of autonomous vtol vehicles  

NASA Astrophysics Data System (ADS)

This paper describes an integrated path planning and tracking control framework for autonomous vertical-take-off-and-landing (VTOL) vehicles, particularly quadrotors. The path planning adopts a receding horizon strategy to repeatedly plan a local trajectory that satisfies both the vehicle dynamics and obstacle-free requirement. A tracking controller is then designed to track the planned path. The differential flatness property of the quadrotor is exploited in both path planner and tracking controller designs. The proposed framework is verified by real-time simulations incorporating online optimization.

Liu, C.; Chen, W.-H.

2013-12-01

73

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

74

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

75

Evaluation of glide paths for landing a VTOL airplane using linear regulator theory.  

NASA Technical Reports Server (NTRS)

A method of evaluating certain characteristics of approach paths for VTOL airplanes is presented which is based on the solution of the matrix Riccati equation to obtain an optimal state variable feedback controller. The longitudinal equations of motion of the airplane are linearized about a preselected path and the resulting system of equations is treated as a linear, time-varying regulator. The controller which minimizes a quadratic cost function is applied to the linearized system to determine the airplane's ability to return to the prescribed path given a specified initial error in altitude. The procedure is applied to the XC-142A, tilt-wing, V/STOL airplane, under decelerating approach conditions with a glide path consisting of two segments, the first having a smaller angle of descent than the second.

Reid, G. F.; Montgomery, R. C.; Hasdorff, L.

1973-01-01

76

Ground-simulation investigation of VTOL instrument flight rules airworthiness criteria  

NASA Technical Reports Server (NTRS)

A two-part ground-simulation investigation of VTOL terminal-area operations, conducted as part of a joint NASA/FAA program to develop airworthiness criteria for this class of vehicle, is described. The baseline vehicle selected for the simulations was a generalized version of the XV-15 tilt-rotor mathematical model, which was modified to permit generic variations in forces or moments or both with power or configuration changes. Additionally, changes to wing area and rotor-blade chord were considered as a means of modifying the allowable thrust-angle versus speed relationships (the conversion corridor). The Vertical Motion Simulator at Ames Research Center was used in the experiment. Four engineering test pilots conducted over 200 piloted evaluations examining the influence of the experimental variables on their ability to perform terminal-area operations.

Lebacqz, J. V.; Scott, B. C.

1984-01-01

77

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

78

Control theory analysis of a three-axis VTOL flight director. M.S. Thesis - Pennsylvania State Univ.  

NASA Technical Reports Server (NTRS)

A control theory analysis of a VTOL flight director and the results of a fixed-based simulator evaluation of the flight-director commands are discussed. The VTOL configuration selected for this study is a helicopter-type VTOL which controls the direction of the thrust vector by means of vehicle-attitude changes and, furthermore, employs high-gain attitude stabilization. This configuration is the same as one which was simulated in actual instrument flight tests with a variable stability helicopter. Stability analyses are made for each of the flight-director commands, assuming a single input-output, multi-loop system model for each control axis. The analyses proceed from the inner-loops to the outer-loops, using an analytical pilot model selected on the basis of the innermost-loop dynamics. The time response of the analytical model of the system is primarily used to adjust system gains, while root locus plots are used to identify dominant modes and mode interactions.

Niessen, F. R.

1971-01-01

79

Aircraft Noise  

NASA Astrophysics Data System (ADS)

Aircraft industry is exposed to increasing public pressure aiming at a continuing reduction of aircraft noise levels. This is necessary to both compensate for the detrimental effect on noise of the expected increase in air traffic and improve the quality of living in residential areas around airports.

Michel, Ulf; Dobrzynski, Werner; Splettstoesser, Wolf; Delfs, Jan; Isermann, Ullrich; Obermeier, Frank

80

Carrier aircraft  

NASA Technical Reports Server (NTRS)

The Ohio State University planned to conduct a conceptual design of a single research vehicle that could be used to explore the flight regime from Mach 6 to Mach 12. Since this aircraft will be a special purpose vehicle, it need not take off and land in a conventional manner. Indeed, if this aircraft were launched from a larger aircraft that carried it to altitude, then conventional landing gear would not be needed and the extra weight of the fuel needed to take off and climb into the stratosphere would be eliminated. The focus of the students' project was on the design of a carrier aircraft answering to the specifications. Its mission is to take off with the research aircraft from runways of less than 15,000 feet, climb to 40,000 feet, and release the hypersonic aircraft at the speed of Mach 8, and return to base. The range of this mission is 2000 n.m. This study includes the conception of an optimized aircraft (geometry, weights, propulsion, aerodynamics, interactions between the two aircraft, etc.), the longitudinal stability of the composite, and the separation critical phase.

1990-01-01

81

Aircraft equipment  

NASA Technical Reports Server (NTRS)

The complex of functionally interconnected instruments and devices for controlling flight, engine operations, electrical systems, communications, and vital systems for passengers and crew is described. The aggregates of the aircraft automatic equipment are also discussed.

1977-01-01

82

Modeling and simulation of a VTOL UAV for landing gear performance evaluation  

NASA Astrophysics Data System (ADS)

A multibody dynamics model of a Vertical Take-off and Landing (VTOL) Unmanned Aerial Vehicle (UAV) is presented in this study. The scope of the project was to investigate a lightweight landing gear which has a stable and robust landing performance. Two original designs of the landing gear for the module of interest have been modeled and analyzed in this study. Two new designs have also been developed, modeled, and analyzed. A limited analysis of the forces that occur in the legs/struts has also been performed, to account for possible failure of the members due to buckling. The model incorporates a sloped surface of deformable terrain for stability analysis of the landing scenarios, and unilateral constraints to model the ground reaction forces upon contact. The lift forces on the UAV are modeled as mathematical relations dependent on the speed of the ducted fan to enable the variation of the impact velocities and the different landing scenarios. The simulations conducted illustrate that initial conditions at landing have a big impact on the stability of the module. The two new designs account for the worst possible scenario, and, for the material properties given, end with a larger weight than the one of the original design with three legs and a ring. Simulation data from several landing scenarios are presented in this paper, with analysis of the difference in performance among the different designs.

Chan, Brendan J.; Sandu, Corina; Ko, Andy; Streett, Tim

2007-04-01

83

STOL Aircraft  

NASA Technical Reports Server (NTRS)

Michael E. Fisher, President of AeroVisions International, has introduced the Culex light twin engine aircraft which offers economy of operation of a single engine plane, the ability to fly well on one engine, plus the capability of flying from short, unimproved fields of takeoff and landing distances less than 35 feet. Key element of design is an airfoil developed by Langley. Culex was originally intended to be factory built aircraft for special utility markets. However, it is now offered as a build-it-yourself kit plane.

1988-01-01

84

Development of a GPS/INS/MAG navigation system and waypoint navigator for a VTOL UAV  

NASA Astrophysics Data System (ADS)

Unmanned aerial vehicles (UAV) can be used for versatile surveillance and reconnaissance missions. If a UAV is capable of flying automatically on a predefined path the range of possible applications is widened significantly. This paper addresses the development of the integrated GPS/INS/MAG navigation system and a waypoint navigator for a small vertical take-off and landing (VTOL) unmanned four-rotor helicopter with a take-off weight below 1 kg. The core of the navigation system consists of low cost inertial sensors which are continuously aided with GPS, magnetometer compass, and a barometric height information. Due to the fact, that the yaw angle becomes unobservable during hovering flight, the integration with a magnetic compass is mandatory. This integration must be robust with respect to errors caused by the terrestrial magnetic field deviation and interferences from surrounding electronic devices as well as ferrite metals. The described integration concept with a Kalman filter overcomes the problem that erroneous magnetic measurements yield to an attitude error in the roll and pitch axis. The algorithm provides long-term stable navigation information even during GPS outages which is mandatory for the flight control of the UAV. In the second part of the paper the guidance algorithms are discussed in detail. These algorithms allow the UAV to operate in a semi-autonomous mode position hold as well an complete autonomous waypoint mode. In the position hold mode the helicopter maintains its position regardless of wind disturbances which ease the pilot job during hold-and-stare missions. The autonomous waypoint navigator enable the flight outside the range of vision and beyond the range of the radio link. Flight test results of the implemented modes of operation are shown.

Meister, Oliver; Mönikes, Ralf; Wendel, Jan; Frietsch, Natalie; Schlaile, Christian; Trommer, Gert F.

2007-04-01

85

An Examination of Handling Qualities Criteria for V/STOL Aircraft  

NASA Technical Reports Server (NTRS)

A study has been undertaken to define hand-ling qualities criteria for V/STOL aircraft. With the current military requirements for helicopters and airplanes as a framework, modifications and additions were made for conversion to a preliminary set of V/STOL requirements using a broad background of flight experience and pilots' comments from VTOL and STOL aircraft, BLC (boundary-layer-control) equipped aircraft, variable stability aircraft, flight simulators and landing approach studies. The report contains a discussion of the reasoning behind and the sources of information leading to suggested requirements. The results of the study indicate that the majority of V/STOL requirements can be defined by modifications to the helicopter and/or airplane requirements by appropriate definition of reference speeds. Areas where a requirement is included but where the information is felt to be inadequate to establish a firm quantitative requirement include the following: Control power and damping relationships about all axes for various sizes and types of aircraft; control power, sensitivity, d-amping and response for height control; dynamic longitudinal and dynamic lateral- directional stability in the transition region, including emergency operation; hovering steadiness; acceleration and deceleration in transition; descent rates and flight-path angles in steep approaches, and thrust margin for approach.

Anderson, Seth B.

1960-01-01

86

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

87

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

88

Use of active control systems to improve bending and rotor flapping response of a tilt rotor VTOL airplane  

NASA Technical Reports Server (NTRS)

The results are summarized of an analytical study of the use of active control systems for the purpose of reducing the root mean square response of wing vertical bending and rotor flapping to atmospheric turbulence for a tilt-rotor VTOL airplane. Only the wing/rotor assembly was considered so that results of a wind tunnel test program would be applicable in a subsequent phase of the research. The capabilities and limitations of simple single feedback configurations were identified, and the most promising multiloop feedback configurations were then investigated. Design parameters were selected so as to minimize either wing bending or rotor flapping response. Within the constraints imposed by practical levels of feedback gains and complexity and by considerations of safety, reduction in response due to turbulence of the order of 30 to 50 percent is predicted using the rotor longitudinal cyclic and a trailing edge wing flap as control effectors.

Whitaker, H. P.; Cheng, Y.

1975-01-01

89

Investigation of Longitudinal and Lateral Stability Characteristics of a Six-Propeller Deflected-Slipstream VTOL Model with Boundary-Layer Control Including Effects of Ground Proximity  

NASA Technical Reports Server (NTRS)

An investigation of the longitudinal and lateral stability and control and Performance characteristics of a six-propeller deflected- slipstream vertical-take-off-and-landing (VTOL) model in the transition speed range was conducted in the 17-foot test section of the Langley 300-MPH 7- by 10-foot tunnel. A complete analysis of the data was not conducted. A modest amount of blowing boundary-layer control was necessary to achieve transition without wing stall.

Grunwald, Kalman J.

1961-01-01

90

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

91

Aircraft systems cyber security  

Microsoft Academic Search

Presents a collection of slides from the author's conference presentation. Topics covered include: The Transition of Aircraft Systems; The Difference Between Cyber Security in Aircraft Systems and Information Technology (IT); Potential Cyber Security Threats to Aircraft Systems; and FAA Aircraft Systems Cyber Security Activities.

Raymond De Cerchio; Chris Riley

2012-01-01

92

The aircraft rotation problem  

Microsoft Academic Search

Given a set of flights to be flown for a specific aircraft type, with specified maintenance locations, durations, and needed frequency, the aircraft rotation problem is to determine the specific route flown by each aircraft. The objective is to maximize the benefit derived from making specific connections. In this paper, we present a mathematical formulation for the aircraft rotation problem

Lloyd Clarke; Ellis Johnson; George Nemhauser; Zhongxi Zhu

1997-01-01

93

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

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

Propulsion controlled aircraft computer  

NASA Technical Reports Server (NTRS)

A low-cost, easily retrofit Propulsion Controlled Aircraft (PCA) system for use on a wide range of commercial and military aircraft consists of an propulsion controlled aircraft computer that reads in aircraft data including aircraft state, pilot commands and other related data, calculates aircraft throttle position for a given maneuver commanded by the pilot, and then displays both current and calculated throttle position on a cockpit display to show the pilot where to move throttles to achieve the commanded maneuver, or is automatically sent digitally to command the engines directly.

Cogan, Bruce R. (Inventor)

2010-01-01

96

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...

97

Aircraft and air pollution  

SciTech Connect

The Clean Air Act of 1977 directs EPA to issue emission standards for aircraft engines that may contribute to air pollution and thus endanger public health or welfare. Critics argue that the regulations are overly complex and stringent, and that immediate energy shortages may take precedence over the need for aircraft emission controls. Proponents of the regulations claim that ambient air standards are freqeuntly violated and will continue to be unless the best available control technology is applied to all sources, including aircraft. The contribution of aircraft to total emissions is discussed. Engineering problems and costs of retrofitting pollution controls on aircrafts are examined.

Naugle, D.F.; Fox, D.L.

1981-04-01

98

Lateral Stability and Control Characteristics of a Four-Propeller Deflected-Slipstream VTOL Model Including the Effects of Ground Proximity  

NASA Technical Reports Server (NTRS)

The investigation of the lateral-directional stability and control characteristics of a four-propeller deflected-slipstream VTOL model in the transition speed range was conducted in the 17-foot test section of the Langley 300-MPH 7- by 10-foot tunnel. A large fairing on top of the rear fuselage was needed to eliminate directional instability in the power-off flaps-retracted condition. Even with this fairing some instability at small sideslip angles remained for power-on conditions with low flap deflections. The configuration exhibited a high level of dihedral effect which, coupled with the directional instability, will probably produce an undesirable Dutch roll oscillation.

Kuhn, Richard E.; Grunwald, Kalman J.

1961-01-01

99

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

100

Conceptual aircraft dynamics from inverse aircraft modeling  

E-print Network

on which to test their control laws. The method involves the extraction of the aerodynamic and propulsive data from the existing simulation and their subsequent integration into a new nonlinear simulation. The subject aircraft from which the data is derived...

Ziegler, Gregory E

2012-06-07

101

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

102

A head up display format for application to V/STOL aircraft approach and landing  

NASA Technical Reports Server (NTRS)

A head up display (HUD) format developed at NASA Ames Research Center to provide pilots of V/STOL aircraft with complete flight guidance and control information for category-3C terminal-area flight operations, is described in detail. These flight operations cover a large spectrum, from STOL operations on land-based runways to VTOL operations on small ships in high seas. Included in this description is a complete geometrical specification of the HUD elements and their drive laws. The principal features of this display format are the integration of the flightpath and pursuit guidance information into a narrow field of view, easily assimilated by the pilot with a single glance, and the superposition of vertical and horizontal situation information. The display is a derivative of a successful design developed for conventional transport aircraft. The design is the outcome of many piloted simulations conducted over a four-year period. Whereas the concepts on which the display format rests could not be fully exploited because of field-of-view restrictions, and some reservations remain about the acceptability of superimposing vertical and horizontal situation information, the design successfully fulfilled its intended objectives.

Merrick, Vernon K.; Farris, Glenn G.; Vanags, Andrejs A.

1990-01-01

103

Lightning effects on aircraft  

NASA Technical Reports Server (NTRS)

Direct and indirect effects of lightning on aircraft were examined in relation to aircraft design. Specific trends in design leading to more frequent lightning strikes were individually investigated. These trends included the increasing use of miniaturized, solid state components in aircraft electronics and electric power systems. A second trend studied was the increasing use of reinforced plastics and other nonconducting materials in place of aluminum skins, a practice that reduces the electromagnetic shielding furnished by a conductive skin.

1977-01-01

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

A Flight Examination of Operating Problems of V/STOL Aircraft in STOL-Type Landing and Approach  

NASA Technical Reports Server (NTRS)

A flight investigation has been conducted using a large twin-engine cargo aircraft to isolate the problems associated with operating propeller-driven aircraft in the STOL speed range where appreciable engine power is used to augment aerodynamic lift. The problems considered would also be representative of those of a large overloaded VTOL aircraft operating in an STOL manner with comparable thrust-to-weight ratios. The study showed that operation at low approach speeds was compromised by the necessity of maintaining high thrust to generate high lift and yet achieving the low lift-drag ratios needed for steep descents. The useable range of airspeed and flight path angle was limited by the pilot's demand for a positive climb margin at the approach speed, a suitable stall margin, and a control and/or performance margin for one engine inoperative. The optimum approach angle over an obstacle was found to be a compromise between obtaining the shortest air distance and the lowest touchdown velocity. In order to realize the greatest low-speed potential from STOL designs, the stability and control characteristics must be satisfactory.

Innis, Robert C.; Quigley, Hervey C.

1961-01-01

108

Aircraft Cabin Environmental Quality Sensors  

E-print Network

commercial aircraft, for which the minimum cabin pressure isAircraft cabin environment Airliner cabin environmental research American National Standards Institute pressure:and cabin P. The FAA also requires that aircraft maintain air pressures

Gundel, Lara

2010-01-01

109

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

110

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

111

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

112

Civil aircraft accident investigation.  

PubMed

This talk reviews some historic aircraft accidents and some more recent. It reflects on the division of accident causes, considering mechanical failures and aircrew failures, and on aircrew training. Investigation results may lead to improved aircraft design, and to appropriate crew training. PMID:24057309

Haines, Daniel

2013-01-01

113

Aircraft and air pollution  

Microsoft Academic Search

The Clean Air Act of 1977 directs EPA to issue emission standards for aircraft engines that may contribute to air pollution and thus endanger public health or welfare. Critics argue that the regulations are overly complex and stringent, and that immediate energy shortages may take precedence over the need for aircraft emission controls. Proponents of the regulations claim that ambient

Dennis F. Naugle; Donald L. Fox

1981-01-01

114

Solar powered aircraft  

Microsoft Academic Search

A cruciform wing structure for a solar powered aircraft is disclosed. Solar cells are mounted on horizontal wing surfaces. Wing surfaces with spanwise axis perpendicular to surfaces maintain these surfaces normal to the sun's rays by allowing aircraft to be flown in a controlled pattern at a large bank angle. The solar airplane may be of conventional design with respect

1983-01-01

115

Solar thermal aircraft  

Microsoft Academic Search

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

Charles L

2007-01-01

116

Cable Tensiometer for Aircraft  

NASA Technical Reports Server (NTRS)

The invention is a cable tensiometer that can be used on aircraft for real-time, in-flight cable tension measurements. The invention can be used on any aircraft cables with high precision. The invention is extremely light-weight, hangs on the cable being tested and uses a dual bending beam design with a high mill-volt output to determine tension.

Nunnelee, Mark (Inventor)

2008-01-01

117

Health monitoring aircraft  

SciTech Connect

A description is given of the health monitoring aircraft concept, which will incorporate innovative sensors, AI, and advanced analytical techniques to provivide real-time and continual aircraft health assessment. According to this concept, all flight-critical structures will be evaluated for integrity as part of the automated preflight checklist. The pilot will be given a visual display of the health of all systems prior to takeoff. Any in-flight change in the health of the aircraft wil be displayed along with recommended action. In order to achieve these capabilities, state-of-the-art structural integrity computer programs, together with AI/neutral network decision-making software, will be incorporated as part of the aircraft computing capability. The life history of the aircraft will be continually and automaticaly updated so that acccurate structural integrity assessments can be made.

Gerardi, T.G. (USAF, Wright Research and Development Center, Wright-Patterson AFB, OH (USA))

1990-07-01

118

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

119

Aircraft compass characteristics  

NASA Technical Reports Server (NTRS)

A description of the test methods used at the National Bureau of Standards for determining the characteristics of aircraft compasses is given. The methods described are particularly applicable to compasses in which mineral oil is used as the damping liquid. Data on the viscosity and density of certain mineral oils used in United States Navy aircraft compasses are presented. Characteristics of Navy aircraft compasses IV to IX and some other compasses are shown for the range of temperatures experienced in flight. Results of flight tests are presented. These results indicate that the characteristic most desired in a steering compass is a short period and, in a check compass, a low overswing.

Peterson, John B; Smith, Clyde W

1937-01-01

120

Flow simulation for aircraft  

NASA Astrophysics Data System (ADS)

The various aspects of computer simulation of flow about aircrafts, and their role in aircraft design are discussed. The general tendency in the industrial development process to accelerate product innovation by an integrated approach to the design is explained. Experimental wind tunnel investigations and mathematical modeling are discussed as the two available methods for the analysis of flow about aircrafts. The various flow models used in flow simulation are discussed in successive order of decreasing complexity, and their applicability is outlined. The successive steps in flow simulation are presented. The state of the art in relation to computer technology is described. Information aspects of simulation are discussed in general terms.

Loeve, W.; Vandervooren, J.

1987-12-01

121

Heat management system for aircraft  

Microsoft Academic Search

A novel heat management system for aircraft is provided which is based on the aircraft fuel as the heat exchange medium and comprises a dedicated thermal reserves fuel tank for containing refrigerated aircraft fuel (or other expendable liquid) which is cooled by heat exchange with the primary aircraft fuel flow to the engines; a fuel line loop for conducting fuel

1983-01-01

122

The Aircraft Morphing Program  

NASA Technical Reports Server (NTRS)

In the last decade smart technologies have become enablers that cut across traditional boundaries in materials science and engineering. Here we define smart to mean embedded actuation, sensing, and control logic in a tightly coupled feedback loop. While multiple successes have been achieved in the laboratory, we have yet to see the general applicability of smart devices to real aircraft systems. The NASA Aircraft Morphing program is an attempt to couple research across a wide range of disciplines to integrate smart technologies into high payoff aircraft applications. The program bridges research in seven individual disciplines and combines the effort into activities in three primary program thrusts. System studies are used to assess the highest- payoff program objectives, and specific research activities are defined to address the technologies required for development of smart aircraft systems. In this paper we address the overall program goals and programmatic structure, and discuss the challenges associated with bringing the technologies to fruition.

Wlezien, R. W.; Horner, G. C.; McGowan, A. R.; Padula, S. L.; Scott, M. A.; Silcox, R. J.; Simpson, J. O.

1998-01-01

123

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

124

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

125

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

126

Pollution reducing aircraft propulsion  

Microsoft Academic Search

Aircraft engine exhaust is mixed with air and fuel and recombusted. Air is drawn into the secondary combustion chamber from suction surfaces on wings. Exhaust of the secondary combustion chamber is blown over wing and fuselage surfaces.

Tamura

1985-01-01

127

Pollution reducing aircraft propulsion  

SciTech Connect

Aircraft engine exhaust is mixed with air and fuel and recombusted. Air is drawn into the secondary combustion chamber from suction surfaces on wings. Exhaust of the secondary combustion chamber is blown over wing and fuselage surfaces.

Tamura, R. M.

1985-05-28

128

Solar thermal aircraft  

SciTech Connect

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

129

Aircraft Laminar Flow Control  

Microsoft Academic Search

Aircraft laminar flow control (LFC) from the 1930s through the 1990s 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

Ronald D. Joslin

1998-01-01

130

Alternative jet aircraft fuels  

NASA Technical Reports Server (NTRS)

Potential changes in jet aircraft fuel specifications due to shifts in supply and quality of refinery feedstocks are discussed with emphasis on the effects these changes would have on the performance and durability of aircraft engines and fuel systems. Combustion characteristics, fuel thermal stability, and fuel pumpability at low temperature are among the factors considered. Combustor and fuel system technology needs for broad specification fuels are reviewed including prevention of fuel system fouling and fuel system technology for fuels with higher freezing points.

Grobman, J.

1979-01-01

131

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

132

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. (See the Pathfinder Plus photos and project description.)

1995-01-01

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 noise synthesis system  

NASA Technical Reports Server (NTRS)

A second-generation Aircraft Noise Synthesis System has been developed to provide test stimuli for studies of community annoyance to aircraft flyover noise. The computer-based system generates realistic, time-varying, audio simulations of aircraft flyover noise at a specified observer location on the ground. The synthesis takes into account the time-varying aircraft position relative to the observer; specified reference spectra consisting of broadband, narrowband, and pure-tone components; directivity patterns; Doppler shift; atmospheric effects; and ground effects. These parameters can be specified and controlled in such a way as to generate stimuli in which certain noise characteristics, such as duration or tonal content, are independently varied, while the remaining characteristics, such as broadband content, are held constant. The system can also generate simulations of the predicted noise characteristics of future aircraft. A description of the synthesis system and a discussion of the algorithms and methods used to generate the simulations are provided. An appendix describing the input data and providing user instructions is also included.

Mccurdy, David A.; Grandle, Robert E.

1987-01-01

135

Aircraft control position indicator  

NASA Technical Reports Server (NTRS)

An aircraft control position indicator was provided that displayed the degree of deflection of the primary flight control surfaces and the manner in which the aircraft responded. The display included a vertical elevator dot/bar graph meter display for indication whether the aircraft will pitch up or down, a horizontal aileron dot/bar graph meter display for indicating whether the aircraft will roll to the left or to the right, and a horizontal dot/bar graph meter display for indicating whether the aircraft will turn left or right. The vertical and horizontal display or displays intersect to form an up/down, left/right type display. Internal electronic display driver means received signals from transducers measuring the control surface deflections and determined the position of the meter indicators on each dot/bar graph meter display. The device allows readability at a glance, easy visual perception in sunlight or shade, near-zero lag in displaying flight control position, and is not affected by gravitational or centrifugal forces.

Dennis, Dale V. (inventor)

1987-01-01

136

Identification of Aircraft Hazards  

SciTech Connect

Aircraft hazards were determined to be potentially applicable to a repository at Yucca Mountain in ''Monitored Geological Repository External Events Hazards Screening Analysis'' (BSC 2005 [DIRS 174235], Section 6.4.1). That determination was conservatively based upon limited knowledge of flight data in the area of concern and upon crash data for aircraft of the type flying near Yucca Mountain. The purpose of this report is to identify specific aircraft hazards that may be applicable to a monitored geologic repository (MGR) at Yucca Mountain, using NUREG-0800, ''Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants'' (NRC 1987 [DIRS 103124], Section 3.5.1.6), as guidance for the inclusion or exclusion of identified aircraft hazards. The intended use of this report is to provide inputs for further screening and analysis of identified aircraft hazards based upon the criteria that apply to Category 1 and Category 2 event sequence analyses as defined in 10 CFR 63.2 [DIRS 176544] (Section 4). The scope of this report includes the evaluation of military, private, and commercial use of airspace in the 100-mile regional setting of the repository at Yucca Mountain with the potential for reducing the regional setting to a more manageable size after consideration of applicable screening criteria (Section 7).

K. Ashley

2006-12-08

137

IDENTIFICATION OF AIRCRAFT HAZARDS  

SciTech Connect

Aircraft hazards were determined to be potentially applicable to a repository at Yucca Mountain in the ''Monitored Geological Repository External Events Hazards Screening Analysis'' (BSC 2004, Section 6.4.1). That determination was conservatively based on limited knowledge of flight data in the area of concern and on crash data for aircraft of the type flying near Yucca Mountain. The purpose of this report is to identify specific aircraft hazards that may be applicable to a Monitored Geologic Repository (MGR) at Yucca Mountain using NUREG-0800, ''Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants'' (NRC 1987, Section 3.5.1.6), as guidance for the inclusion or exclusion of identified aircraft hazards. NUREG-0800 is being used here as a reference because some of the same considerations apply. The intended use of this report is to provide inputs for further screening and analysis of the identified aircraft hazards based on the criteria that apply to Category 1 and 2 event sequence analyses as defined in 10 CFR 63.2 (see Section 4). The scope of this technical report includes the evaluation of military, private, and commercial use of airspace in the 100-mile regional setting of the MGR at Yucca Mountain with the potential for reducing the regional setting to a more manageable size after consideration of applicable screening criteria (see Section 7).

K.L. Ashley

2005-03-23

138

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

139

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

140

Pathfinder aircraft flight  

NASA Technical Reports Server (NTRS)

The Pathfinder research aircraft's wing structure is clearly defined as it soars under a clear blue sky during a test flight from Dryden Flight Research Center, Edwards, California, in November of 1996. Pathfinder was a lightweight, solar-powered, remotely piloted flying wing aircraft used to demonstrate the use of solar power for long-duration, high-altitude flight. Its name denotes its mission as the 'Pathfinder' or first in a series of solar-powered aircraft that will be able to remain airborne for weeks or months on scientific sampling and imaging missions. Solar arrays covered most of the upper wing surface of the Pathfinder aircraft. These arrays provided up to 8,000 watts of power at high noon on a clear summer day. That power fed the aircraft's six electric motors as well as its avionics, communications, and other electrical systems. Pathfinder also had a backup battery system that could provide power for two to five hours, allowing for limited-duration flight after dark. Pathfinder flew at airspeeds of only 15 to 20 mph. Pitch control was maintained by using tiny elevators on the trailing edge of the wing while turns and yaw control were accomplished by slowing down or speeding up the motors on the outboard sections of the wing. On September 11, 1995, Pathfinder set a new altitude record for solar-powered aircraft of 50,567 feet above Edwards Air Force Base, California, on a 12-hour flight. On July 7, 1997, it set another, unofficial record of 71,500 feet at the Pacific Missile Range Facility, Kauai, Hawaii. In 1998, Pathfinder was modified into the longer-winged Pathfinder Plus configuration. (See the Pathfinder Plus photos and project description.)

1996-01-01

141

Pathfinder aircraft in flight  

NASA Technical Reports Server (NTRS)

The unique Pathfinder solar-powered flying wing, is shown during a checkout flight from the Dryden Flight Research Center, Edwards, California. This two-hour low-altitude flight over Rogers Dry Lake, Nov. 19, 1996, served to test aircraft systems and functional procedures, according to officials of AeroVironment, Inc., Pathfinder's developer and operator. Pathfinder was a lightweight, solar-powered, remotely piloted flying wing aircraft used to demonstrate the use of solar power for long-duration, high-altitude flight. Its name denotes its mission as the 'Pathfinder' or first in a series of solar-powered aircraft that will be able to remain airborne for weeks or months on scientific sampling and imaging missions. Solar arrays covered most of the upper wing surface of the Pathfinder aircraft. These arrays provided up to 8,000 watts of power at high noon on a clear summer day. That power fed the aircraft's six electric motors as well as its avionics, communications, and other electrical systems. Pathfinder also had a backup battery system that could provide power for two to five hours, allowing for limited-duration flight after dark. Pathfinder flew at airspeeds of only 15 to 20 mph. Pitch control was maintained by using tiny elevators on the trailing edge of the wing while turns and yaw control were accomplished by slowing down or speeding up the motors on the outboard sections of the wing. On September 11, 1995, Pathfinder set a new altitude record for solar-powered aircraft of 50,567 feet above Edwards Air Force Base, California, on a 12-hour flight. On July 7, 1997, it set another, unofficial record of 71,500 feet at the Pacific Missile Range Facility, Kauai, Hawaii. In 1998, Pathfinder was modified into the longer-winged Pathfinder Plus configuration. (See the Pathfinder Plus photos and project description.)

1996-01-01

142

Pathfinder aircraft checkout flight  

NASA Technical Reports Server (NTRS)

The Pathfinder solar-powered research aircraft is silhouetted against a clear blue sky as it soars aloft during a checkout flight from the Dryden Flight Research Center, Edwards, California, in November, 1996. Pathfinder was a lightweight, solar-powered, remotely piloted flying wing aircraft used to demonstrate the use of solar power for long-duration, high-altitude flight. Its name denotes its mission as the 'Pathfinder' or first in a series of solar-powered aircraft that will be able to remain airborne for weeks or months on scientific sampling and imaging missions. Solar arrays covered most of the upper wing surface of the Pathfinder aircraft. These arrays provided up to 8,000 watts of power at high noon on a clear summer day. That power fed the aircraft's six electric motors as well as its avionics, communications, and other electrical systems. Pathfinder also had a backup battery system that could provide power for two to five hours, allowing for limited-duration flight after dark. Pathfinder flew at airspeeds of only 15 to 20 mph. Pitch control was maintained by using tiny elevators on the trailing edge of the wing while turns and yaw control were accomplished by slowing down or speeding up the motors on the outboard sections of the wing. On September 11, 1995, Pathfinder set a new altitude record for solar-powered aircraft of 50,567 feet above Edwards Air Force Base, California, on a 12-hour flight. On July 7, 1997, it set another, unofficial record of 71,500 feet at the Pacific Missile Range Facility, Kauai, Hawaii. In 1998, Pathfinder was modified into the longer-winged Pathfinder Plus configuration. (See the Pathfinder Plus photos and project description.)

1996-01-01

143

Pathfinder aircraft in flight  

NASA Technical Reports Server (NTRS)

The Pathfinder solar-powered research aircraft is silhouetted against a clear blue sky as it soars aloft during a checkout flight from the Dryden Flight Research Center, Edwards, California, November, 1996. Pathfinder was a lightweight, solar-powered, remotely piloted flying wing aircraft used to demonstrate the use of solar power for long-duration, high-altitude flight. Its name denotes its mission as the 'Pathfinder' or first in a series of solar-powered aircraft that will be able to remain airborne for weeks or months on scientific sampling and imaging missions. Solar arrays covered most of the upper wing surface of the Pathfinder aircraft. These arrays provided up to 8,000 watts of power at high noon on a clear summer day. That power fed the aircraft's six electric motors as well as its avionics, communications, and other electrical systems. Pathfinder also had a backup battery system that could provide power for two to five hours, allowing for limited-duration flight after dark. Pathfinder flew at airspeeds of only 15 to 20 mph. Pitch control was maintained by using tiny elevators on the trailing edge of the wing while turns and yaw control were accomplished by slowing down or speeding up the motors on the outboard sections of the wing. On September 11, 1995, Pathfinder set a new altitude record for solar-powered aircraft of 50,567 feet above Edwards Air Force Base, California, on a 12-hour flight. On July 7, 1997, it set another, unofficial record of 71,500 feet at the Pacific Missile Range Facility, Kauai, Hawaii. In 1998, Pathfinder was modified into the longer-winged Pathfinder Plus configuration. (See the Pathfinder Plus photos and project description.)

1996-01-01

144

Pathfinder aircraft in flight  

NASA Technical Reports Server (NTRS)

The Pathfinder research aircraft's solar cell arrays are prominently displayed as it touches down on the bed of Rogers Dry Lake at the Dryden Flight Research Center, Edwards, California, following a test flight. The solar arrays covered more than 75 percent of Pathfinder's upper wing surface, and provided electricity to power its six electric motors, flight controls, communications links and a host of scientific sensors. Pathfinder was a lightweight, solar-powered, remotely piloted flying wing aircraft used to demonstrate the use of solar power for long-duration, high-altitude flight. Its name denotes its mission as the 'Pathfinder' or first in a series of solar-powered aircraft that will be able to remain airborne for weeks or months on scientific sampling and imaging missions. Solar arrays covered most of the upper wing surface of the Pathfinder aircraft. These arrays provided up to 8,000 watts of power at high noon on a clear summer day. That power fed the aircraft's six electric motors as well as its avionics, communications, and other electrical systems. Pathfinder also had a backup battery system that could provide power for two to five hours, allowing for limited-duration flight after dark. Pathfinder flew at airspeeds of only 15 to 20 mph. Pitch control was maintained by using tiny elevators on the trailing edge of the wing while turns and yaw control were accomplished by slowing down or speeding up the motors on the outboard sections of the wing. On September 11, 1995, Pathfinder set a new altitude record for solar-powered aircraft of 50,567 feet above Edwards Air Force Base, California, on a 12-hour flight. On July 7, 1997, it set another, unofficial record of 71,500 feet at the Pacific Missile Range Facility, Kauai, Hawaii. In 1998, Pathfinder was modified into the longer-winged Pathfinder Plus configuration. (See the Pathfinder Plus photos and project description.)

1996-01-01

145

Pathfinder aircraft in flight  

NASA Technical Reports Server (NTRS)

The Pathfinder solar-powered research aircraft heads for landing on the bed of Rogers Dry Lake at the Dryden Flight Research Center, Edwards, California, after a successful test flight Nov. 19, 1996. Pathfinder was a lightweight, solar-powered, remotely piloted flying wing aircraft used to demonstrate the use of solar power for long-duration, high-altitude flight. Its name denotes its mission as the 'Pathfinder' or first in a series of solar-powered aircraft that will be able to remain airborne for weeks or months on scientific sampling and imaging missions. Solar arrays covered most of the upper wing surface of the Pathfinder aircraft. These arrays provided up to 8,000 watts of power at high noon on a clear summer day. That power fed the aircraft's six electric motors as well as its avionics, communications, and other electrical systems. Pathfinder also had a backup battery system that could provide power for two to five hours, allowing for limited-duration flight after dark. Pathfinder flew at airspeeds of only 15 to 20 mph. Pitch control was maintained by using tiny elevators on the trailing edge of the wing while turns and yaw control were accomplished by slowing down or speeding up the motors on the outboard sections of the wing. On September 11, 1995, Pathfinder set a new altitude record for solar-powered aircraft of 50,567 feet above Edwards Air Force Base, California, on a 12-hour flight. On July 7, 1997, it set another, unofficial record of 71,500 feet at the Pacific Missile Range Facility, Kauai, Hawaii. In 1998, Pathfinder was modified into the longer-winged Pathfinder Plus configuration. (See the Pathfinder Plus photos and project description.)

1996-01-01

146

Aircraft surface coatings  

NASA Technical Reports Server (NTRS)

Liquid, spray on elastomeric polyurethanes are selected and investigated as best candidates for aircraft external protective coatings. Flight tests are conducted to measure drag effects of these coatings compared to paints and a bare metal surface. The durability of two elastometric polyurethanes are assessed in airline flight service evaluations. Laboratory tests are performed to determine corrosion protection properties, compatibility with aircraft thermal anti-icing systems, the effect of coating thickness on erosion durability, and the erosion characteristics of composite leading edges-bare and coated. A cost and benefits assessment is made to determine the economic value of various coating configurations to the airlines.

1982-01-01

147

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

148

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

149

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... AIR PROGRAMS (CONTINUED) CONTROL OF AIR POLLUTION FROM AIRCRAFT AND AIRCRAFT ENGINES General Provisions § 87.6 Aircraft...

2011-07-01

150

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 Protection... AIR PROGRAMS (CONTINUED) CONTROL OF AIR POLLUTION FROM AIRCRAFT AND AIRCRAFT ENGINES General Provisions § 87.6 Aircraft...

2013-07-01

151

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

152

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

153

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

154

Bibliography for aircraft parameter estimation  

NASA Technical Reports Server (NTRS)

An extensive bibliography in the field of aircraft parameter estimation has been compiled. This list contains definitive works related to most aircraft parameter estimation approaches. Theoretical studies as well as practical applications are included. Many of these publications are pertinent to subjects peripherally related to parameter estimation, such as aircraft maneuver design or instrumentation considerations.

Iliff, Kenneth W.; Maine, Richard E.

1986-01-01

155

Aircraft Cabin Environmental Quality Sensors  

E-print Network

requires that aircraft maintain air pressures equivalent toair quality (CO, O 3 , ventilation and pressure) are adequate to protect health and are met by commercial aircraft.air pressure, jet lag, inactivity, humidity, duty schedules, fatigue, circadian rhythm, stress and noise, in several types of aircraft.

Gundel, Lara

2010-01-01

156

Passenger aircraft cabin air quality  

Microsoft Academic Search

Background Pressurization of aircraft passenger cabins in the 1940s permitted operation at higher ceilings. This substantially reduced aircraft drag, decreasing fuel costs by 38% (at 30,000 ft, 9140 m, compared to at sea level), but pressurization of the outside air required for ventilation adds up to 2% to fuel costs. Today some 50% of commercial passenger aircraft use recirculated air

Martin B. Hocking

2000-01-01

157

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

158

Aircraft Morphing program  

Microsoft Academic Search

In the last decade smart technologies have become enablers that cut across traditional boundaries in materials science and engineering. Here we define smart to mean embedded actuation, sensing, and control logic in a tightly coupled feedback loop. While multiple successes have been achieved in the laboratory, we have yet to see the general applicability of smart devices to real aircraft

Richard W. Wlezien; Garnett C. Horner; Anna-Maria Rivas McGowan; S. L. Padula; Michael A. Scott; Richard J. Silcox; Joycelyn O. Simpson

1998-01-01

159

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

160

Cooperation in aircraft design  

Microsoft Academic Search

We describe how aircraft are designed in a large organization. We discuss the different phases of design and interaction with the customer. We then describe the models used by each specialist department and the interactions among departments during the design process. We observe that the main design choices are refinement operations on the design. We then briefly describe how the

Alan H. Bond; Richard J. Ricci

1992-01-01

161

Cooperation in Aircraft Design  

Microsoft Academic Search

We describe how aircraft are designed in a large organization. We discuss the interactions among the different specialist departments during the design process, and the models used by each department. We observe that the main design choices are refinement operations on the design. The overall structure of the organized design process is one of coordinated refinement of models. We describe

Alan H. Bond; Richard J. Ricci

1989-01-01

162

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

163

The solar aircraft  

NASA Technical Reports Server (NTRS)

A discussion is given in a popular manner of the solar powered aircraft Solair I. The achievements of the designer are detailed, and trial runs leading up to the first successful flight are given. Technical data of Solair I are listed, and brief news items about it are presented.

1983-01-01

164

Ozone and aircraft operations  

NASA Astrophysics Data System (ADS)

The cabin ozone problem is discussed. Cabin ozone in terms of health effects, the characteristics of ozone encounters by aircraft, a brief history of studies to define the problem, corrective actions taken, and possible future courses of action are examined. It is suggested that such actions include avoiding high ozone concentrations by applying ozone forecasting in flight planning procedures.

Perkins, P. J.

1981-12-01

165

Counterrotating aircraft propulsor blades  

NASA Technical Reports Server (NTRS)

A propulsor blade for an aircraft engine includes an airfoil section formed in the shape of a scimitar. A metallic blade spar is interposed between opposed surfaces of the blade and is bonded to the surfaces to establish structural integrity of the blade. The metallic blade spar includes a root end allowing attachment of the blade to the engine.

Nelson, Joey L. (Inventor); Elston, III, Sidney B. (Inventor); Tseng, Wu-Yang (Inventor); Hemsworth, Martin C. (Inventor)

1993-01-01

166

Agent aided aircraft maintenance  

Microsoft Academic Search

Aircraft maintenance is performed by mechanics who are required,by regulation, to consult expert engineers for repairinstructions and approval. In addition to their own experience,these engineers rely on external information sources,which are often inadequately indexed and geographicallydispersed. The timely retrieval of this distributed informationis vital to the engineers\\

Onn Shehory; Katia P. Sycara; Gita Sukthankar; Vick Mukherjee

1999-01-01

167

Advanced ATC: An aircraft perspective  

NASA Technical Reports Server (NTRS)

The principal operational improvements desired by commercial aircraft operators in the United States are efficient aircraft operations and delay reductions at the major terminals. Efforts underway within the Advanced Transport Operating Systems Program at the Langley Research Center to provide a technology basis for reducing delay while improving aircraft efficiency are discussed. The principal thrust is the development of time-based traffic control concepts which could be used within the framework of the upgraded National Airspace System and which would allow conventionally equipped aircraft to operate in a manner compatible with advanced aircraft.

Credeur, Leonard; Williams, David H.; Howell, William E.; Spitzer, Cary R.

1986-01-01

168

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

169

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 efficient 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

170

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

171

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

172

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

173

Nonlinear control of aircraft  

NASA Technical Reports Server (NTRS)

Transformations of nonlinear systems were used to design automatic flight controllers for vertical and short takeoff aircraft. Under the assumption that a nonlinear system can be mapped to a controllable linear system, a method using partial differential equations was constructed to approximate transformations in cases where exact ones cannot be found. An application of the design theory to a rotorcraft, the UH-1H helicopter, was presented.

Hunt, L. R.; Meyer, G.; Su, R.

1984-01-01

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

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

176

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

177

NASA research in aircraft propulsion  

NASA Technical Reports Server (NTRS)

A broad overview of the scope of research presently being supported by NASA in aircraft propulsion is presented with emphasis on Lewis Research Center activities related to civil air transports, CTOL and V/STOL systems. Aircraft systems work is performed to identify the requirements for the propulsion system that enhance the mission capabilities of the aircraft. This important source of innovation and creativity drives the direction of propulsion research. In a companion effort, component research of a generic nature is performed to provide a better basis for design and provides an evolutionary process for technological growth that increases the capabilities of all types of aircraft. Both are important.

Beheim, M. A.

1982-01-01

178

Future short-field aircraft  

NASA Technical Reports Server (NTRS)

The application of short takeoff and landing aircraft for improving short-haul air transportation is examined. The contracts with industry to study quiet turbofan short-field aircraft in the short-haul air transportation system are identified. Studies of appropriate propulsion systems are conducted in parallel with the aircraft studies. The objectives of the studies are to: (1) determine economic and social viability of short-haul air transportation, (2) identify critical technology and technology-related problems, (3) define representative aircraft configurations and characteristics to include development and operational costs, and (4) to establish desirable technology advances for improving short-haul transportation systems.

Galloway, T. L.

1972-01-01

179

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

180

Aircraft surface coatings  

NASA Technical Reports Server (NTRS)

A series of studies in which films and liquid spray-on materials were evaluated in the laboratory for transport aircraft external surface coatings are summarized. Elastomeric polyurethanes were found to best meet requirements. Two commercially available products, CAAPCO B-274 and Chemglaze M313, were subjected to further laboratory testing, airline service evaluations, and drag-measurement flight tests. It was found that these coatings were compatible with the severe operating environment of airlines and that coatings reduced airplane drag. An economic analysis indicated significant dollar benefits to airlines from application of the coatings.

1983-01-01

181

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

182

Aircraft engine emission reduction  

SciTech Connect

The paper discusses new concepts for combustion chambers to help create low pollution power plants and reduce engine emissions. Researchers see that internal combustion engines provide complete combustion when they are close to stoichiometry while gas turbines experience problems when they reach this ratio. It would be best to modify the equivalence ratio of the primary combustion zone which is responsible for the high level of NOx emissions. Reduction of pollutant emissions from aircraft engines are focused on three areas: (1) use of less polluting fuels; (2) modification of the combustion process; and (3) reduction of specific fuel consumption and consequently consumption overall.

Birch, S.

1994-01-01

183

Structural integrity in aircraft.  

NASA Technical Reports Server (NTRS)

The paper reviews briefly the current design philosophies for achieving long, efficient, and reliable service in aircraft structures. The strengths and weaknesses of these design philosophies and their demonstrated records of success are discussed. The state of the art has not been developed to the point where designing can be done without major test inspection and maintenance programs. A broad program of research is proposed through which a viable computerized design scheme will be provided during the next decade. The program will organize and correlate existing knowledge on fatigue and fracture behavior, identify gaps in this knowledge, and guide specific research to upgrade design capabilities.

Hardrath, H. F.

1973-01-01

184

14 CFR 252.13 - Small aircraft.  

Code of Federal Regulations, 2013 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....

2013-01-01

185

14 CFR 252.13 - Small aircraft.  

Code of Federal Regulations, 2012 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....

2012-01-01

186

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

187

14 CFR 252.13 - Small aircraft.  

...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....

2014-01-01

188

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

189

14 CFR 21.127 - Tests: aircraft.  

Code of Federal Regulations, 2011 CFR

...form, flight test each aircraft produced. (b...that the production aircraft has the same range and degree of control as the prototype aircraft. (2) An operational check of each part or system operated by the...

2011-01-01

190

14 CFR 135.25 - Aircraft requirements.  

Code of Federal Regulations, 2013 CFR

...Aviation if— (1) The aircraft carries an appropriate...country; (2) The aircraft is of a type design which is approved under...be applicable to that aircraft were it registered...certificate (including type design conformity,...

2013-01-01

191

14 CFR 135.25 - Aircraft requirements.  

Code of Federal Regulations, 2010 CFR

...Aviation if— (1) The aircraft carries an appropriate...country; (2) The aircraft is of a type design which is approved under...be applicable to that aircraft were it registered...certificate (including type design conformity,...

2010-01-01

192

14 CFR 135.25 - Aircraft requirements.  

Code of Federal Regulations, 2012 CFR

...Aviation if— (1) The aircraft carries an appropriate...country; (2) The aircraft is of a type design which is approved under...be applicable to that aircraft were it registered...certificate (including type design conformity,...

2012-01-01

193

14 CFR 135.25 - Aircraft requirements.  

Code of Federal Regulations, 2011 CFR

...Aviation if— (1) The aircraft carries an appropriate...country; (2) The aircraft is of a type design which is approved under...be applicable to that aircraft were it registered...certificate (including type design conformity,...

2011-01-01

194

A Ubiquitous Computing Environment for Aircraft Maintenance  

E-print Network

. General Terms Design, Economics, Human Factors. Keywords Aircraft maintenance, ubiquitous computing, assetA Ubiquitous Computing Environment for Aircraft Maintenance Matthias Lampe Department of Computer in the area of aircraft maintenance. Extensive requirements regarding quality, safety, and documentation

195

14 CFR 135.25 - Aircraft requirements.  

...Aviation if— (1) The aircraft carries an appropriate...country; (2) The aircraft is of a type design which is approved under...be applicable to that aircraft were it registered...certificate (including type design conformity,...

2014-01-01

196

19 CFR 122.42 - Aircraft entry.  

Code of Federal Regulations, 2012 CFR

... Aircraft Entry and Entry Documents; Electronic Manifest Requirements for Passengers, Crew Members, and Non-Crew Members Onboard Commercial Aircraft Arriving In, Continuing Within, and Overflying the United States § 122.42 Aircraft entry....

2012-04-01

197

19 CFR 122.42 - Aircraft entry.  

... Aircraft Entry and Entry Documents; Electronic Manifest Requirements for Passengers, Crew Members, and Non-Crew Members Onboard Commercial Aircraft Arriving In, Continuing Within, and Overflying the United States § 122.42 Aircraft entry....

2014-04-01

198

19 CFR 122.42 - Aircraft entry.  

Code of Federal Regulations, 2013 CFR

... Aircraft Entry and Entry Documents; Electronic Manifest Requirements for Passengers, Crew Members, and Non-Crew Members Onboard Commercial Aircraft Arriving In, Continuing Within, and Overflying the United States § 122.42 Aircraft entry....

2013-04-01

199

19 CFR 122.42 - Aircraft entry.  

Code of Federal Regulations, 2011 CFR

... Aircraft Entry and Entry Documents; Electronic Manifest Requirements for Passengers, Crew Members, and Non-Crew Members Onboard Commercial Aircraft Arriving In, Continuing Within, and Overflying the United States § 122.42 Aircraft entry....

2011-04-01

200

14 CFR 141.39 - Aircraft.  

Code of Federal Regulations, 2012 CFR

... (1) Is either a civil aircraft of the United States or a civil aircraft of foreign registry; ...with the requirements for aircraft operated for hire under part...accordance with equivalent maintenance and inspection from the...

2012-01-01

201

14 CFR 141.39 - Aircraft.  

Code of Federal Regulations, 2011 CFR

... (1) Is either a civil aircraft of the United States or a civil aircraft of foreign registry; ...with the requirements for aircraft operated for hire under part...accordance with equivalent maintenance and inspection from the...

2011-01-01

202

14 CFR 141.39 - Aircraft.  

... (1) Is either a civil aircraft of the United States or a civil aircraft of foreign registry; ...with the requirements for aircraft operated for hire under part...accordance with equivalent maintenance and inspection from the...

2014-01-01

203

Altus aircraft on runway  

NASA Technical Reports Server (NTRS)

The remotely piloted Altus aircraft flew several developmental test flights from Rogers Dry Lake adjacent to NASA's Dryden Flight Research Center, Edwards, Calif., in 1996. The Altus--the word is Latin for 'high'--is a variant of the Predator surveillance drone built by General Atomics/Aeronautical Systems, Inc. It is designed for high-altitude, long-duration scientific sampling missions, and is powered by a turbocharged four-cylinder piston engine. The first Altus was developed under NASA's Environmental Research Aircraft and Sensor Technology program, while a second Altus was built for a Naval Postgraduate School/Department of Energy program. A pilot in a control station on the ground flew the craft by radio signals, using visual cues from a video camera in the nose of the Altus and information from the craft's air data system. Equipped with a single-stage turbocharger during the 1996 test flights, the first Altus reached altitudes in the 37,000-foot range, while the similarly-equipped second Altus reached 43,500 feet during developmental flights at Dryden in the summer of 1997. The NASA Altus also set an endurance record of more than 26 hours while flying a science mission in late 1996 and still had an estimated 10 hours of fuel remaining when it landed. Now equipped with a two-stage turbocharger, the NASA Altus maintained an altitude of 55,000 feet for four hours during flight tests in 1999.

1996-01-01

204

Hypersonic transport aircraft  

NASA Technical Reports Server (NTRS)

A hypersonic transport aircraft design project was selected as a result of interactions with NASA Lewis Research Center personnel and fits the Presidential concept of the Orient Express. The Graduate Teaching Assistant (GTA) and an undergraduate student worked at the NASA Lewis Research Center during the 1986 summer conducting a literature survey, and relevant literature and useful software were collected. The computer software was implemented in the Computer Aided Design Laboratory of the Mechanical and Aerospace Engineering Department. In addition to the lectures by the three instructors, a series of guest lectures was conducted. The first of these lectures 'Anywhere in the World in Two Hours' was delivered by R. Luidens of NASA Lewis Center. In addition, videotaped copies of relevant seminars obtained from NASA Lewis were also featured. The first assignment was to individually research and develop the mission requirements and to discuss the findings with the class. The class in consultation with the instructors then developed a set of unified mission requirements. Then the class was divided into three design groups (1) Aerodynamics Group, (2) Propulsion Group, and (3) Structures and Thermal Analyses Group. The groups worked on their respective design areas and interacted with each other to finally come up with an integrated conceptual design. The three faculty members and the GTA acted as the resource persons for the three groups and aided in the integration of the individual group designs into the final design of a hypersonic aircraft.

1987-01-01

205

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

206

Aircraft wiring program status report  

NASA Astrophysics Data System (ADS)

In this Naval Air Warfare Center (NAWC) Aircraft Division status report, the general and wire and cable component activities, the systems engineering activities, the aircraft wiring lead maintenance activities, the NAVAIR/NASA interface activities, and the Base Realignment and Closure (BRAC) Commission recommendations are presented.

Beach, Rex

1995-11-01

207

Aircraft wiring program status report  

Microsoft Academic Search

In this Naval Air Warfare Center (NAWC) Aircraft Division status report, the general and wire and cable component activities, the systems engineering activities, the aircraft wiring lead maintenance activities, the NAVAIR\\/NASA interface activities, and the Base Realignment and Closure (BRAC) Commission recommendations are presented.

Rex Beach

1995-01-01

208

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

209

Aircraft as a meteorological sensor  

E-print Network

Aircraft as a meteorological sensor Using Mode-S Enhanced Surveillance data to derive upper air for arrival management of LVNL. A second goal is the provision of meteorological data to airlines and other Meteorological Institute 2 | The aircraft as a meteorological sensor Photo cover: A KLM Airbus A330-200 lands

Haak, Hein

210

The Ultra Light Aircraft Testing  

NASA Technical Reports Server (NTRS)

The final report for grant NAG1-345 is presented. Recently, the bulk of the work that the grant has supported has been in the areas of ride quality and the structural analysis and testing of ultralight aircraft. The ride quality work ended in May 1989. Hence, the papers presented in this final report are concerned with ultralight aircraft.

Smith, Howard W.

1993-01-01

211

Aircraft wiring program status report  

NASA Technical Reports Server (NTRS)

In this Naval Air Warfare Center (NAWC) Aircraft Division status report, the general and wire and cable component activities, the systems engineering activities, the aircraft wiring lead maintenance activities, the NAVAIR/NASA interface activities, and the Base Realignment and Closure (BRAC) Commission recommendations are presented.

Beach, Rex

1995-01-01

212

Power electronics transforms aircraft systems  

Microsoft Academic Search

This paper describes the secondary power sources available on a large transport aircraft and discusses expectation that power electronics will enable the transforming of present aircraft systems into new highly integrated systems. The benefits expected from integrating all of the engine-based hydraulic and pneumatic power sources into a single electrical system are identified in qualitative terms. The estimated capacity of

L. J. Feiner

1994-01-01

213

Human systems and aircraft maintenance  

Microsoft Academic Search

Research in normal operational environments indicates that the formal requirements for the aircraft maintenance system are frequently not fully or effectively implemented in practice. This gives rise to a pervasive ‘double standard’ with no effective means of reconciling official and unofficial operational practice. A systems strategy for human-centred management in aircraft maintenance is being developed in a number of European

Nick McDonald

2001-01-01

214

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

215

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

216

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

217

Aircraft agility maneuvers  

NASA Technical Reports Server (NTRS)

A new dynamic model for aircraft motions is presented. This model can be viewed as intermediate between a point-mass model, in which the body attitude angles are control-like, and a rigid-body model, in which the body-attitude angles evolve according to Newton's Laws. Specifically, consideration is given to the case of symmetric flight, and a model is constructed in which the body roll-rate and the body pitch-rate are the controls. In terms of this body-rate model a minimum-time heading change maneuver is formulated. When the bounds on the body-rates are large the results are similar to the point-mass model in that the model can very quickly change the applied forces and produce an acceleration to turn the vehicle. With finite bounds on these rates, the forces change in a smooth way. This leads to a measurable effect of agility.

Cliff, Eugene M.; Thompson, Brian G.

1992-01-01

218

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

219

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

220

Restructurable controls for aircraft  

NASA Technical Reports Server (NTRS)

Future aircraft with highly sophisticated controls are likely to have multiple interdependent failure modes which will be difficult for the pilot to recognize. Such failures may lead to unanticipated sequences of events from which the pilot cannot intuitively recover. Advances in the state-of-the-art in failure detection, failure identification, and control system technology suggest it may be feasible to detect and identify potentially catastrophic failures in flight controls and to restructure the controls in real time to execute a safe landing. Two accidents are reviewed, one in which the pilot successfully restructured the controls and one in which he did not, but for which a solution existed. The problem requirements and potential theoretical techniques which apply are also discussed.

Howell, W. E.; Bundick, W. T.; Hueschen, R. M.; Ostroff, A. J.

1983-01-01

221

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

222

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

223

36 CFR 327.4 - Aircraft.  

Code of Federal Regulations, 2013 CFR

36 Parks, Forests, and Public Property...327.4 Parks, Forests, and Public Property...DEPARTMENT OF THE ARMY RULES... Aircraft. (a) This section...helicopters, ultra-light aircraft, motorized...equipment. (b) The operation of aircraft...aircraft used in emergency...

2013-07-01

224

36 CFR 327.4 - Aircraft.  

Code of Federal Regulations, 2012 CFR

36 Parks, Forests, and Public Property...327.4 Parks, Forests, and Public Property...DEPARTMENT OF THE ARMY RULES... Aircraft. (a) This section...helicopters, ultra-light aircraft, motorized...equipment. (b) The operation of aircraft...aircraft used in emergency...

2012-07-01

225

36 CFR 327.4 - Aircraft.  

Code of Federal Regulations, 2011 CFR

36 Parks, Forests, and Public Property...327.4 Parks, Forests, and Public Property...DEPARTMENT OF THE ARMY RULES... Aircraft. (a) This section...helicopters, ultra-light aircraft, motorized...equipment. (b) The operation of aircraft...aircraft used in emergency...

2011-07-01

226

Combat aircraft noise: The operator's perspective  

Microsoft Academic Search

Combat aircraft are not subject to the same noise reduction regulations as civil aircraft. Additionally, combat aircraft are operated closer to their performance limits and at high power settings for extended periods. There is general pressure to reduce noise of all kinds, but particularly noise from low flying aircraft. Although there is little that can be done to quiet in-service

R. Bogg

1992-01-01

227

V/STOL aircraft and fluid dynamic  

NASA Astrophysics Data System (ADS)

The impact of military applications on rotorcraft and V/STOL aircraft design with respect to fixed wing aircraft is discussed. The influence of the mission needs on the configurational design of V/STOL aircraft, the implications regarding some problems in fluid dynamics relating to propulsive flows, and their interaction with the aircraft and the ground plane, are summarized.

Roberts, L.; Anderson, S. B.

1982-01-01

228

Safety factors in civil aircraft design requirements  

Microsoft Academic Search

Many factors influence the safety of modern civil aircraft. Some are related to design, others to the maintenance and operation of the aircraft. The factors and approaches employed vary with the type of aircraft. Those related to structural design relevant to large transport aircraft and to helicopters will be addressed in this paper.The means by which current and developing airworthiness

John W. Bristow; P. E. Irving

2007-01-01

229

Aviation Safety Program Aircraft Aging & Durability Project  

E-print Network

of NASA to improve aircraft safety for current and future civilian and military aircraft, and to overcomeAviation Safety Program Aircraft Aging & Durability Project Technical Plan Summary Principal by NASA to define the rationale, scope and detailed content of a comprehensive Aviation Safety, Aircraft

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

TEAMS: technical expert aircraft maintenance system  

Microsoft Academic Search

The technical expert aircraft maintenance system (TEAMS) is an interactive system that supports the diagnosis of problems on new aircraft. The system uses expert system technology to provide the aircraft mechanic with the knowledge and experience needed to successfully repair an aircraft. TEAMS consists of a number of expert-system modules. The authors give an overview of the TEAMS effort, a

M. P. Lischke; K. L. Mayer

1992-01-01

232

Advanced turboprop cargo aircraft systems study  

NASA Technical Reports Server (NTRS)

Parametric studies were conducted to define the effects of advanced propeller (propfan) characteristics on aircraft direct operating costs, fuel consumption, and noiseprints. Selected propfan aircraft realized 21-percent fuel savings and 15-percent lower DOCs relative to advanced turbofan aircraft. While both the propfan and turbofan aircraft satisfied current federal noise regulations, the propfan aircraft had smaller noiseprints at 90-EPNdB noise levels but larger noiseprints at lower noise levels. Several techniques for reducing the propfan aircraft noiseprints were explored; some of these contribute substantial reductions in noiseprint areas. Also, a propfan aircraft for the C-X role was studied.

Muehlbauer, J. C.; Morris, S. J.

1981-01-01

233

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

234

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

235

Light aircraft sound transmission study  

NASA Astrophysics Data System (ADS)

The plausibility of using the two microphone sound intensity technique to study noise transmission into light aircraft was investigated. In addition, a simple model to predict the interior sound pressure level of the cabin was constructed.

Heitman, K.; Bernhard, R. J.

1983-10-01

236

Powered-lift aircraft technology  

NASA Technical Reports Server (NTRS)

Powered lift aircraft have the ability to vary the magnitude and direction of the force produced by the propulsion system so as to control the overall lift and streamwise force components of the aircraft, with the objective of enabling the aircraft to operate from minimum sized terminal sites. Power lift technology has contributed to the development of the jet lift Harrier and to the forth coming operational V-22 Tilt Rotor and the C-17 military transport. This technology will soon be expanded to include supersonic fighters with short takeoff and vertical landing capability, and will continue to be used for the development of short- and vertical-takeoff and landing transport. An overview of this field of aeronautical technology is provided for several types of powered lift aircraft. It focuses on the description of various powered lift concepts and their operational capability. Aspects of aerodynamics and flight controls pertinent to powered lift are also discussed.

Deckert, W. H.; Franklin, J. A.

1989-01-01

237

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

238

Light aircraft sound transmission study  

NASA Technical Reports Server (NTRS)

The plausibility of using the two microphone sound intensity technique to study noise transmission into light aircraft was investigated. In addition, a simple model to predict the interior sound pressure level of the cabin was constructed.

Heitman, K.; Bernhard, R. J.

1983-01-01

239

Propulsion integration for military aircraft  

NASA Technical Reports Server (NTRS)

The transonic aerodynamic characteristics for high-performance aircraft are significantly affected by shock-induced flow interactions as well as other local flow interference effects which usually occur at transonic speeds. These adverse interactions can not only cause high drag, but can cause unusual aerodynamic loadings and/or severe stability and control problems. Many new programs are underway to develop methods for reducing the adverse effects, as well as to develop an understanding of the basic flow conditions which are the primary contributors. It is anticipated that these new programs will result in technologies which can reduce the aircraft cruise drag through improved integration as well as increased aircraft maneuverability throughh the application of thrust vectoring. This paper will identify some of the primary propulsion integration problems for high performance aircraft at transonic speeds, and demonstrate several methods for reducing or eliminating the undesirable characteristics, while enhancing configuration effectiveness.

Henderson, William P.

1989-01-01

240

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

241

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

242

Future Civil Aircraft and Technologies  

NASA Technical Reports Server (NTRS)

New aircraft technologies are presented that have the potential to expand the air transportation system and reduce congestion through new operating capabilities while also providing greater levels of safety and environmental compatibility. These new capabilities will result from current and planned civil aeronautics technology at the NASA Ames, Lewis, and Langley Research Centers and will cover the complete spectrum of current aircraft and new vehicle concepts including rotorcraft (helicopters and tilt rotors), vertical and short takeoff and landing (V/STOL), and short takeoff and landing (STOL) aircraft, subsonic transports, high-speed transports, and hypersonic/transatmospheric vehicles. New technologies will improve efficiency, affordability, safety, and environmental compatibility of current aircraft and will enable the development of new transportation system. The new capabilities of vehicles could lead to substantial market opportunities and economic growth and could improve the competitive position of the U.S. aerospace industry.

Albers, J.; Zuk, J.

1989-01-01

243

Aircraft recognition and tracking device  

NASA Astrophysics Data System (ADS)

The technology of aircraft recognition and tracking has various applications in all areas of air navigation, be they civil or military, spanning from air traffic control and regulation at civilian airports to anti-aircraft weapon handling and guidance for military purposes.1, 18 The system presented in this thesis is an alternative implementation of identifying and tracking flying objects, which benefits from the optical spectrum by using an optical camera built into a servo motor (pan-tilt unit). More specifically, through the purpose-developed software, when a target (aircraft) enters the field of view of the camera18, it is both detected and identified.5, 22 Then the servo motor, being provided with data on target position and velocity, tracks the aircraft while it is in constant communication with the camera (Fig. 1). All the features are so designed as to operate under real time conditions.

Filis, Dimitrios P.; Renios, Christos I.

2011-11-01

244

Langley Aircraft Landing Dynamics Facility  

NASA Technical Reports Server (NTRS)

The Langley Research Center has recently upgraded the Landing Loads Track (LLT) to improve the capability of low-cost testing of conventional and advanced landing gear systems. The unique feature of the Langley Aircraft Landing Dynamics Facility (ALDF) is the ability to test aircraft landing gear systems on actual runway surfaces at operational ground speeds and loading conditions. A historical overview of the original LLT is given, followed by a detailed description of the new ALDF systems and operational capabilities.

Davis, Pamela A.; Stubbs, Sandy M.; Tanner, John A.

1987-01-01

245

Advanced supersonic cruise aircraft technology  

NASA Technical Reports Server (NTRS)

A multidiscipline approach is taken to the application of the latest technology to supersonic cruise aircraft concept definition, and current problem areas are identified. Particular attention is given to the performance of the AST-100 advanced supersonic cruise vehicle with emphasis on aerodynamic characteristics, noise and chemical emission, and mission analysis. A recently developed aircraft sizing and performance computer program was used to determine allowable wing loading and takeoff gross weight sensitivity to structural weight reduction.

Baber, H. T., Jr.; Driver, C.

1977-01-01

246

Neural networks for aircraft control  

NASA Technical Reports Server (NTRS)

Current research in Artificial Neural Networks indicates that networks offer some potential advantages in adaptation and fault tolerance. This research is directed at determining the possible applicability of neural networks to aircraft control. The first application will be to aircraft trim. Neural network node characteristics, network topology and operation, neural network learning and example histories using neighboring optimal control with a neural net are discussed.

Linse, Dennis

1990-01-01

247

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

248

A study of commuter aircraft design  

NASA Technical Reports Server (NTRS)

This paper investigates the impact of configuration considerations, mission requirements, and performance constraints on conceptual commuter aircraft designs. Emphasis is placed on direct comparisons between turbofan and turboprop powered aircraft in the 10-30 passenger class. The analysis is accomplished using a computerized aircraft synthesis model that simulates the aircraft design and mission. The resulting conceptual aircraft are similar in size and performance regardless of engine type but the turboprop offers more mission flexibility

Galloway, T. L.

1977-01-01

249

Optimization in fractional aircraft ownership  

NASA Astrophysics Data System (ADS)

Fractional Aircraft Ownership is a new concept in flight ownership management system where each individual or corporation may own a fraction of an aircraft. In this system, the owners have privilege to schedule their flight according to their needs. Fractional management companies (FMC) manages all aspects of aircraft operations, including utilization of FMC's aircraft in combination of outsourced aircrafts. This gives the owners the right to enjoy the benefits of private aviations. However, FMC may have complicated business requirements that neither commercial airlines nor charter airlines faces. Here, optimization models are constructed to minimize the number of aircrafts in order to maximize the profit and to minimize the daily operating cost. In this paper, three kinds of demand scenarios are made to represent different flight operations from different types of fractional owners. The problems are formulated as an optimization of profit and a daily operational cost to find the optimum flight assignments satisfying the weekly and daily demand respectively from the owners. Numerical results are obtained by Genetic Algorithm method.

Septiani, R. D.; Pasaribu, H. M.; Soewono, E.; Fayalita, R. A.

2012-05-01

250

Innovations in Aircraft Design  

NASA Technical Reports Server (NTRS)

The Boeing 777 carries with it basic and applied research, technology, and aerodynamic knowledge honed at several NASA field centers. Several Langley Research Center innovations instrumental to the development of the aircraft include knowledge of how to reduce engine and other noise for passengers and terminal residents, increased use of lightweight aerospace composite structures for increased fuel efficiency and range, and wind tunnel tests confirming the structural integrity of 777 wing-airframe integration. Test results from Marshall Space Flight Center aimed at improving the performance of the Space Shuttle engines led to improvements in the airplane's new, more efficient jet engines. Finally, fostered by Ames Research Center, the Boeing 777 blankets that protect areas of the plane from high temperatures and fire have a lineage to Advanced Flexible Reusable Surface Insulation used on certain areas of the Space Shuttle. According to Boeing Company estimates, the 777 has captured three-quarters of new orders for airplanes in its class since the program was launched.

1997-01-01

251

Laser aircraft. [using kerosene  

NASA Technical Reports Server (NTRS)

The concept of a laser-powered aircraft is discussed. Laser flight would be completely compatible with existing airports and air-traffic control, with the airplane using kerosene only power, up to a cruising altitude of 9 km where the laser satellite would lock on and beam laser energy to it. Two major components make up the laser turbofan, a heat exchanger for converting laser radiation into thermal energy, and conventional turbomachinery. The laser power satellite would put out 42 Mw using a solar-powered thermal engine to generate electrical power for the closed-cycle supersonic electric discharge CO laser, whose radiators, heat exchangers, supersonic diffuser, and ducting will amount to 85% of the total subsystem mass. Relay satellites will be used to intercept the beam from the laser satellite, correct outgoing beam aberrations, and direct the beam to the next target. A 300-airplane fleet with transcontinental range is projected to save enough kerosene to equal the energy content of the entire system, including power and relay satellites, in one year.

Hertzberg, A.; Sun, K.; Jones, W. S.

1979-01-01

252

75 FR 50865 - Airworthiness Directives; Various Aircraft Equipped With Rotax Aircraft Engines 912 A Series Engines  

Federal Register 2010, 2011, 2012, 2013

...Metalurgica Ltda. Diamond Aircraft Industries... HK 36...DIMONA''. Diamond Aircraft Industries... HK 36...912 A3. Diamond Aircraft Industries DA20-A1...Subject (d) Air Transport Association...states: Due to high fuel pressure, caused by...

2010-08-18

253

75 FR 32315 - Airworthiness Directives; Various Aircraft Equipped With Rotax Aircraft Engines 912 A Series Engines  

Federal Register 2010, 2011, 2012, 2013

...Metalurgica ltda. Diamond Aircraft Industries... HK 36...DIMONA''. Diamond Aircraft Industries HK 36 TS...912 A3. Diamond Aircraft Industries DA20-A1...Subject (d) Air Transport Association...states: Due to high fuel pressure, caused by...

2010-06-08

254

75 FR 922 - Notification and Reporting of Aircraft Accidents or Incidents and Overdue Aircraft, and...  

Federal Register 2010, 2011, 2012, 2013

...sections have separated from an aircraft. The commenter stated that...of a propeller blade from an aircraft, inconsistent with its design parameters and certification...more than 50 percent of an aircraft's certified electronic...

2010-01-07

255

78 FR 1253 - Schweizer Aircraft Corporation, a Subsidiary of Sikorsky Aircraft Corporation, a Division of...  

Federal Register 2010, 2011, 2012, 2013

...Subsidiary of Sikorsky Aircraft Corporation, a Division...Cameron Mfg. and Design, Inc., Express Employment...subsidiary of Sikorsky Aircraft Corporation, a division...Cameron Mfg. and Design, Inc., Express Employment...Workers of Schweizer Aircraft Corporation, a...

2013-01-08

256

76 FR 31465 - Airworthiness Directives; Various Aircraft Equipped With Rotax Aircraft Engines 912 A Series Engine  

Federal Register 2010, 2011, 2012, 2013

...Directives; Various Aircraft Equipped With Rotax Aircraft Engines 912 A Series...have been shipped as spare parts. This condition...have been shipped as spare parts. This condition...Service Information Rotax Aircraft Engines has...

2011-06-01

257

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

258

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

259

Eclipse program QF-106 aircraft  

NASA Technical Reports Server (NTRS)

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

1996-01-01

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

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

262

Vision assisted aircraft lateral navigation  

NASA Astrophysics Data System (ADS)

Surface operation is currently one of the least technologically equipped phases of aircraft operation. The increased air traffic congestion necessitates more aircraft operations in degraded weather and at night. The traditional surface procedures worked well in most cases as airport surfaces have not been congested and airport layouts were less complex. Despite the best efforts of FAA and other safety agencies, runway incursions continue to occur frequently due to incorrect surface operation. Several studies conducted by FAA suggest that pilot induced error contributes significantly to runway incursions. Further, the report attributes pilot's lack of situational awareness - local (e.g., minimizing lateral deviation), global (e.g., traffic in the vicinity) and route (e.g., distance to next turn) - to the problem. An Enhanced Vision System (EVS) is one concept that is being considered to resolve these issues. These systems use on-board sensors to provide situational awareness under poor visibility conditions. In this paper, we propose the use of an Image processing based system to estimate the aircraft position and orientation relative to taxiway markings to use as lateral guidance aid. We estimate aircraft yaw angle and lateral offset from slope of the taxiway centerline and horizontal position of vanishing line. Unlike automotive applications, several cues such as aircraft maneuvers along assigned route with minimal deviations, clear ground markings, even taxiway surface, limited aircraft speed are available and enable us to implement significant algorithm optimizations. We present experimental results to show high precision navigation accuracy with sensitivity analysis with respect to camera mount, optics, and image processing error.

Mohideen, Mohamed Ibrahim; Ramegowda, Dinesh; Seiler, Peter

2013-05-01

263

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

264

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

265

V/STOL aircraft concepts  

NASA Technical Reports Server (NTRS)

The Potential for V/STOL Aircraft Concepts for Air Transportation in the CALIFORNIA CORRIDOR in the 2010 time period is projected. The project description is to study the potential for V/STOL aircraft concepts in air transportation within the California Corridor, and emphasize V/STOL configurations that are innovative and unconventional in design for use in the 2010 time period. The project is consistent with the mission of the NASA/Ames Research Center and succeeding classes at Cal Poly can iterate and refine for meaningful results for NASA.

1987-01-01

266

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

267

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

268

78 FR 42417 - Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes  

Federal Register 2010, 2011, 2012, 2013

...pilatus-aircraft.com or email: aircraft.com">fodermatt@pilatus-aircraft.com. You may review copies...installed in various airframes and spare parts during the production...Service Information Pilatus Aircraft Ltd. has issued...

2013-07-16

269

77 FR 50954 - Airworthiness Directives; Cessna Aircraft Company  

Federal Register 2010, 2011, 2012, 2013

...scope of the Agency's authority...of civil aircraft in air commerce...Aircraft Company: Docket...to Cessna Aircraft Company (Cessna...Subject Joint Aircraft System Component...JASC)/Air Transport Association...when the pilot set...

2012-08-23

270

77 FR 69742 - Airworthiness Directives; Cessna Aircraft Company Airplanes  

Federal Register 2010, 2011, 2012, 2013

...scope of the Agency's authority...of civil aircraft in air commerce...Aircraft Company: Amendment...to Cessna Aircraft Company (Cessna...Subject Joint Aircraft System Component...JASC)/Air Transport Association...when the pilot set...

2012-11-21

271

Global Mortality Attributable to Aircraft Cruise Emissions  

E-print Network

Aircraft emissions impact human health though degradation of air quality. The majority of previous analyses of air quality impacts from aviation have considered only landing and takeoff emissions. We show that aircraft ...

Britter, Rex E.

272

Simulation of Supersonic Military Aircraft Jet Noise.  

National Technical Information Service (NTIS)

There is a growing need to reduce significantly the noise generated by high-performance, supersonic military aircraft. The noise generated during takeoff and landing on aircraft carriers has direct impact on shipboard health and safety issues. Also, noise...

J. Liu, K. Kailasanath, R. Ramamurti

2009-01-01

273

36 CFR 331.14 - Aircraft.  

Code of Federal Regulations, 2012 CFR

...REGULATIONS GOVERNING THE PROTECTION, USE AND MANAGEMENT OF THE FALLS OF THE OHIO NATIONAL WILDLIFE CONSERVATION AREA, KENTUCKY AND INDIANA § 331.14 Aircraft. (a) The operation of aircraft on WCA lands and waters is prohibited, unless authorized in...

2012-07-01

274

36 CFR 331.14 - Aircraft.  

Code of Federal Regulations, 2011 CFR

...REGULATIONS GOVERNING THE PROTECTION, USE AND MANAGEMENT OF THE FALLS OF THE OHIO NATIONAL WILDLIFE CONSERVATION AREA, KENTUCKY AND INDIANA § 331.14 Aircraft. (a) The operation of aircraft on WCA lands and waters is prohibited, unless authorized in...

2011-07-01

275

36 CFR 331.14 - Aircraft.  

...REGULATIONS GOVERNING THE PROTECTION, USE AND MANAGEMENT OF THE FALLS OF THE OHIO NATIONAL WILDLIFE CONSERVATION AREA, KENTUCKY AND INDIANA § 331.14 Aircraft. (a) The operation of aircraft on WCA lands and waters is prohibited, unless authorized in...

2014-07-01

276

36 CFR 331.14 - Aircraft.  

Code of Federal Regulations, 2013 CFR

...REGULATIONS GOVERNING THE PROTECTION, USE AND MANAGEMENT OF THE FALLS OF THE OHIO NATIONAL WILDLIFE CONSERVATION AREA, KENTUCKY AND INDIANA § 331.14 Aircraft. (a) The operation of aircraft on WCA lands and waters is prohibited, unless authorized in...

2013-07-01

277

36 CFR 331.14 - Aircraft.  

Code of Federal Regulations, 2010 CFR

...REGULATIONS GOVERNING THE PROTECTION, USE AND MANAGEMENT OF THE FALLS OF THE OHIO NATIONAL WILDLIFE CONSERVATION AREA, KENTUCKY AND INDIANA § 331.14 Aircraft. (a) The operation of aircraft on WCA lands and waters is prohibited, unless authorized in...

2010-07-01

278

Unmanned Aircraft Systems at NASA Dryden  

NASA Video Gallery

NASA Dryden has a heritage of developmental and operational experience with unmanned aircraft systems. Work on Boeing's sub-scale X-36 Tailless Fighter Agility Research Aircraft, X-48 Blended Wing ...

279

14 CFR 93.83 - Aircraft operations.  

Code of Federal Regulations, 2011 CFR

...Terminal Area § 93.83 Aircraft operations. (a) North-South Corridor. Unless otherwise authorized by ATC...no person may operate an aircraft in flight within the North-South Corridor designated in § 93.81(b)(1)...

2011-01-01

280

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

281

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

282

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

283

AIRCRAFT RECONNAISSANCE 5.1. General. All Department of Commerce (DOC) tropical and subtropical cyclone aircraft  

E-print Network

Surveillance Aircraft 5.2.3. DOT. The DOT is responsible for providing air traffic control services to aircraft.4.2.1. Geographic Position. Aircraft position: within 3 nm. Storm surface center (wind/pressure): within 6 nm5-1 CHAPTER 5 AIRCRAFT RECONNAISSANCE 5.1. General. All Department of Commerce (DOC) tropical

284

77 FR 1626 - Airworthiness Directives; Various Aircraft Equipped With Rotax Aircraft Engines 912 A Series Engine  

Federal Register 2010, 2011, 2012, 2013

...aircraft equipped with Rotax Aircraft Engines 912 A series engine...http://www.rotax-aircraft-engines.com. You may...sets have also been shipped as spare parts. This condition, if...Relevant Service Information Rotax Aircraft Engines BRP has issued...

2012-01-11

285

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

E-print Network

and Components Transportation Power Generation Portable Power Solid Oxide Fuel Cells Aircraft and Aircaft Support Working Group Explore aircraft primary power and auxiliary power needs. Fixed wing, rotorcraft, highFuel Cell Council Working Group on Aircraft and Aircraft Ground Support Fuel Cell Applications #12

286

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

287

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

288

Progress in supersonic cruise aircraft technology  

NASA Technical Reports Server (NTRS)

The supersonic cruise aircraft research program identified significant improvements in the technology areas of propulsion, aerodynamics, structures, takeoff and landing procedures, and advanced configuration concepts. Application of these technology areas to a commercial aircraft is discussed. An advanced SST family of aircraft which may be environmentally acceptable, have flexible range-payload capability, and be economically viable is projected.

Driver, C.

1978-01-01

289

14 CFR 21.127 - Tests: aircraft.  

Code of Federal Regulations, 2010 CFR

...establish that the production aircraft has the same range and degree of control as the prototype aircraft. (2) An operational...placards and required flight manuals are installed after flight...operational characteristics of the aircraft on the ground. (5) A...

2010-01-01

290

Cognitive failure analysis for aircraft accident investigation  

Microsoft Academic Search

The present studies were undertaken to investigate the applicability of an information processing approach to human failure in the aircraft cockpit. Using data obtained from official aircraft accident investigation reports, a database of accidents and incidents involving New Zealand civil aircraft between 1982 and 1991 was compiled. In the first study, reports were coded into one of three error stages

DAVID OHARE; MARK WIGGINS; RICHARD BATT; DIANNE MORRISON

1994-01-01

291

Operational Experiences of General Aviation Aircraft  

NASA Technical Reports Server (NTRS)

An investigation is currently under way to determine the operational practices and load experiences of general aviation aircraft performing five basic types of operations: twin-engine executive, single-engine executive, personal, instructional, and commercial survey. Limited data obtained to date from aircraft engaged in these operations indicate that aircraft are generally being operated within the limits to which they were designed.

Jewel, Joseph W., Jr.; Walker, Walter G.

1965-01-01

292

Analyses of Aircraft Responses to Atmospheric Turbulence  

Microsoft Academic Search

The response of aircraft to stochastic atmospheric turbulence plays an important role in aircraft-design (load calculations), Flight Control System (FCS) design and flight-simulation (handling qualities research and pilot training). In order to simulate these aircraft responses, an accurate mathematical model is required. Two classical models will be discussed in this thesis, that is the Delft University of Technology (DUT) model

W. H. J. J. Van Staveren

2003-01-01

293

A Graduate Team Aircraft Design Stanford University  

E-print Network

The A Graduate Team Aircraft Design Stanford University June 1, 1999 #12;The Cardinal: A 1999 AIAA Graduate Team Aircraft Design "When I was a student in college, just flying an airplane seemed a dream a dream..." ~Charles Lindbergh JUNE 1, 1999 #12;The Cardinal: A 1999 AIAA Graduate Team Aircraft Design

Stanford University

294

Page 1 of 2 OSU Aircraft Design  

E-print Network

Page 1 of 2 OSU Aircraft Design OSU/UML/NASA OSGC UAFS Airshow and Flight Competition Saturday April 30 (Rain Day, Saturday, May 14) Rules for "Speedfest" Competition Aircraft Requirements - Electric propulsion current must pass through this single. fuse It must be accessible from the outside of the aircraft

Ghajar, Afshin J.

295

RADM Denny Dwyer PEO Aircraft Carriers  

E-print Network

Design for Human Systems Integration #12;1/12/2010 PEO Aircraft Carriers 9 CVN 21 Concept Ship Flight Added UNCLASSIFIED #12;1/12/2010 PEO Aircraft Carriers 10 CVN 21 Concept Ship Flight Deck CVN 21 Design Aircraft Carriers 12 Take Aways CVN 21 Design is a series of Systems Engineering trade- offs. Moving CVN

296

Development of Approach Procedures for Silent Aircraft  

Microsoft Academic Search

Aircraft technology and operational procedures need to be designed in parallel to meet the Silent Aircraft Initiative noise goal of being below ambient noise levels outside the perimeter of a typical urban airport. Technologies have been incorporated into a conceptual Silent Aircraft blended-wing-body type design allowing a slow and steep continuous descent approach trajectory with a displaced landing threshold. Through

James I. Hileman; Tom G. Reynolds; Thomas R. Law; Steven Thomas

2007-01-01

297

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's perceptions of unmanned aircraft in the United States. Some of the questions were replicated from a previous

McShea, Daniel W.

298

Application of modern aluminum alloys to aircraft  

Microsoft Academic Search

Aluminum alloys have been the primary material of choice for structural components of aircraft since about 1930. Although polymer matrix composites are being used extensively in high-performance military aircraft and are being specified for some applications in modern commercial aircraft, aluminum alloys are the overwhelming choice for the fuselage, wing, and supporting structure of commercial airliners and military cargo and

E. A. Starke; J. T. Staley

1996-01-01

299

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

300

Managing IT investment for aircraft sustainment  

E-print Network

for managing investment in aircraft spares. Case study 1: the process reference model, referred of spare parts to support aircraft operations. Airlines and maintenance providers typically followManaging IT investment for aircraft sustainment Michael MacDonnell, Department of Management

de Weck, Olivier L.

301

Bayesian Methods for Aircraft Structural Health  

E-print Network

their periodic inspection and maintenance. While taking the aircraft out of service is quite costlyChapter 1 Bayesian Methods for Aircraft Structural Health Monitoring T.C. Henderson1 , V.J. Mathews.1 Introduction Aircraft structures, whether metallic or composite, are subject to service damage which requires

Henderson, Thomas C.

302

Fault knowledge management in aircraft maintenance  

Microsoft Academic Search

An aircraft is complex system with a great number of electronic products and mechanical equipments, and numerous faults failed to be inspected in aircraft maintenance. In most circumstance, it requires specialists to detect, diagnose and redress faults. The expert knowledge is an important aid in aircraft maintenance. This paper proposes a knowledge management method based on much maintenance experience and

Yang Zhou; Qing Li; Yingping Zuo

2009-01-01

303

Navigation system of pilotless aircraft via GPS  

Microsoft Academic Search

The pilotless aircraft has wide applications in measuring earth, surveying mineral sources, fireproofing in the forest, observing floods and so on. In this paper, after briefly introducing positioning and navigation technologies for pilotless aircraft-a new kind of navigation system for pilotless aircraft using GPS (Global Positioning System) is presented. An overall plan of the navigation system is discussed, and its

Yongsheng Wang; Xiangpeng Li; Yong Huang

1996-01-01

304

Computing small-fleet aircraft availabilities including redundancy and spares  

Microsoft Academic Search

Logistics support is a key element of aircraft transportation systems. This paper is concerned with the impact of aircraft spares provisioning decisions on the availability of aircraft. Spares provisioning in this context is complicated by the fact that spares may be shared across aircraft and that aircraft may have redundant systems. In addition, decisions concerning aircraft spares support require a

Jeffery K. Cochran; Theodore P. Lewis

2002-01-01

305

Aircraft flight test trajectory control  

NASA Technical Reports Server (NTRS)

Two design techniques for linear flight test trajectory controllers (FTTCs) are described: Eigenstructure assignment and the minimum error excitation technique. The two techniques are used to design FTTCs for an F-15 aircraft model for eight different maneuvers at thirty different flight conditions. An evaluation of the FTTCs is presented.

Menon, P. K. A.; Walker, R. A.

1988-01-01

306

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

307

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

308

Fretting in aircraft turbine engines  

NASA Technical Reports Server (NTRS)

The problem of fretting in aircraft turbine engines is discussed. Critical fretting can occur on fan, compressor, and turbine blade mountings, as well as on splines, rolling element bearing races, and secondary sealing elements of face type seals. Structural fatigue failures have been shown to occur at fretted areas on component parts. Methods used by designers to reduce the effects of fretting are given.

Johnson, R. L.; Bill, R. C.

1974-01-01

309

Computational Aerodynamics for Aircraft Design  

Microsoft Academic Search

This article outlines some of the principal issues in the development of numerical methods for the prediction of flows over aircraft and their use in the design process. These include the choice of an appropriate mathematical model, the design of shock-capturing algorithms, the treatment of complex geometric configurations, and shape modifications to optimize the aerodynamic performance.

Antony Jameson

1989-01-01

310

Visualization for multiparameter aircraft designs  

Microsoft Academic Search

We describe an aircraft design problem in high dimen- sional space, with D typically being 10 to 30. In some respects this is a classic optimization problem, where the goal is to find the point that minimizes an objective function while satisfying a set of constraints. However, evaluating an individual point is expensive, and the high dimensionality makes many approaches

Clifford A. Shaffer; Duane L. Knill; Layne T. Watson

1998-01-01

311

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

312

FOR AIRCRAFT ENGINE FAULT DIAGNOSTICS  

Microsoft Academic Search

Accurate and timely detection and diagnosis of aircraft engine fault is critical to the normal operation of engine\\/airplane and to maintain them in a healthy state. In engine fault diagnostics, engine gas path measurements, such as exhaust gas temperature (EGT), fuel flow (WF) and core speed (N2), etc. are frequently used. Some diagnostics models employ trend shift detection for these

Xiao Hu; Neil Eklund; Kai Goebel

313

IDS: Improving Aircraft Fleet Maintenance  

Microsoft Academic Search

This paper describes the Integrated Diagnostic System (IDS), an applied AI project concerned with the development of hybrid information systems to diagnose problems and help manage repair processes of commercial aircraft fleets. A study at one major airline indicated that significant bene- fits could accrue (approximately 2% of overall maintenance budget) through the use of innovative information technol- ogy. The

Rob Wylie; Robert Orchard; Michael Halasz; François Dubé

1997-01-01

314

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

315

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

316

75 FR 5203 - Certification of Aircraft and Airmen for the Operation of Light-Sport Aircraft; Modifications to...  

Federal Register 2010, 2011, 2012, 2013

...Aircraft and Airmen for the Operation of Light-Sport Aircraft; Modifications to Rules...Aircraft and Airmen for the Operation of Light- Sport Aircraft; Modifications to Rules...aircraft and airmen for the operation of light-sport aircraft were implemented in...

2010-02-01

317

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

318

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

319

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

320

Mathematical treatment of aircraft maneuvers  

NASA Astrophysics Data System (ADS)

This work addresses the problem faced by an aircraft that is off its nominal flight path. The goal is to find the optimal trajectory to safely and efficiently return the aircraft to its proper path in rugged terrain. The authors approach to this problem is to consider the space of possible trajectories as a series of linked maneuvers, so that a particular trajectory can be described by the ordered list of parameters specifying the maneuvers. A penalty function is minimized with respect to variations of the maneuver parameter list. The work considered trajectories of up to three straight flight segments linked by turns. The penalty function includes terms penalizing elapsed time for the measure, distance climbed, and closest approach to the ground as well as distance from the nominal flight path at the end of the maneuver. Minimization is performed by means of an adaptive fuzzy-logic-enhanced genetic algorithm.

Kim, Dai Hyun; Kostrzewski, Andrew A.; Ro, Sookwang; Wang, Wenjian; Savant, Gajendra D.; Erwin, Daniel A.; Snow, Michael P.

2000-07-01

321

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

322

Trends in transport aircraft avionics  

NASA Technical Reports Server (NTRS)

A survey of avionics onboard present commercial transport aircraft was conducted to identify trends in avionics systems characteristics and to determine the impact of technology advances on equipment weight, cost, reliability, and maintainability. Transport aircraft avionics systems are described under the headings of communication, navigation, flight control, and instrumentation. The equipment included in each section is described functionally. However, since more detailed descriptions of the equipment can be found in other sources, the description is limited and emphasis is put on configuration requirements. Since airborne avionics systems must interface with ground facilities, certain ground facilities are described as they relate to the airborne systems, with special emphasis on air traffic control and all-weather landing capability.

Berkstresser, B. K.

1973-01-01

323

Aircraft flight test trajectory control  

NASA Technical Reports Server (NTRS)

Two control law design techniques are compared and the performance of the resulting controllers evaluated. The design requirement is for a flight test trajectory controller (FTTC) capable of closed-loop, outer-loop control of an F-15 aircraft performing high-quality research flight test maneuvers. The maneuver modeling, linearization, and design methodologies utilized in this research, are detailed. The results of applying these FTTCs to a nonlinear F-15 simulation are presented.

Menon, P. K. A.; Walker, R. A.

1988-01-01

324

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

325

Contrail formation in aircraft wakes  

Microsoft Academic Search

The process of the formation and early evolution of a condensation trail (`contrail') in the near field of an aircraft wake was numerically studied by means of a mixed Eulerian\\/Lagrangian two-phase flow approach. Large-eddy simulations were used for the carrier phase, while, for the dispersed phase, a Lagrangian particle tracking method was used, coupled with a microphysics model to account

Roberto Paoli; Jerome Hélie; Thierry Poinsot

2004-01-01

326

Stochastic Methods for Aircraft Design  

NASA Technical Reports Server (NTRS)

The global stochastic optimization method, simulated annealing (SA), was adapted and applied to various problems in aircraft design. The research was aimed at overcoming the problem of finding an optimal design in a space with multiple minima and roughness ubiquitous to numerically generated nonlinear objective functions. SA was modified to reduce the number of objective function evaluations for an optimal design, historically the main criticism of stochastic methods. SA was applied to many CFD/MDO problems including: low sonic-boom bodies, minimum drag on supersonic fore-bodies, minimum drag on supersonic aeroelastic fore-bodies, minimum drag on HSCT aeroelastic wings, FLOPS preliminary design code, another preliminary aircraft design study with vortex lattice aerodynamics, HSR complete aircraft aerodynamics. In every case, SA provided a simple, robust and reliable optimization method which found optimal designs in order 100 objective function evaluations. Perhaps most importantly, from this academic/industrial project, technology has been successfully transferred; this method is the method of choice for optimization problems at Northrop Grumman.

Pelz, Richard B.; Ogot, Madara

1998-01-01

327

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

328

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

329

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

330

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

331

AIRTV: Broadband Direct to Aircraft  

NASA Astrophysics Data System (ADS)

Airlines have been continuously upgrading their wide-body, long-haul aircraft with IFE (in-flight entertainment) systems that can support from 12 to 24 channels of video entertainment as well as provide the infrastructure to enable in-seat delivery of email and internet services. This is a direct consequence of increased passenger demands for improved in-flight services along with the expectations that broadband delivery systems capable of providing live entertainment (news, sports, financial information, etc.) and high speed data delivery will soon be available. The recent events of Sept. 11 have slowed the airline's upgrade of their IFE systems, but have also highlighted the compelling need for broadband aeronautical delivery systems to include operational and safety information. Despite the impact of these events, it is estimated that by 2005 more than 3000 long haul aircraft (servicing approximately 1 billion passengers annually) will be fully equipped with modern IFE systems. Current aircraft data delivery systems, which use either Inmarsat or NATS, are lacking in bandwidth and consequently are unsuitable to satisfy passenger demands for broadband email/internet services or the airlines' burgeoning data requirements. Present live video delivery services are limited to regional coverage and are not readily expandable to global or multiregional service. Faced with a compelling market demand for high data transport to aircraft, AirTV has been developing a broadband delivery system that will meet both passengers' and airlines' needs. AirTV is a global content delivery system designed to provide a range of video programming and data services to commercial airlines. When AirTV is operational in 2004, it will provide a broadband connection directly to the aircraft, delivering live video entertainment, internet/email service and essential operational and safety data. The system has been designed to provide seamless global service to all airline routes except for those over the poles. The system consists of a constellation of 4 geostationary satellites covering the earth and delivering its signals to the aircraft at S band (2.52 -2.67 GHz). The S-band spectrum is ideal for this application since it is allocated on a primary basis by the ITU for global broadcast service. The AirTV service is expected to begin in 2004 and should be unencumbered by adjacent satellite interference due to near completion of the ITU coordination process. Each satellite will deliver four 20 Mbps QPSK data streams consisting of multiplexed compressed digital video channels and IP data over the full global beam coverage. The 80 Mbps capacity of each satellite will provide approximately 60 video channels while still allocating 40 Mbits to data services. The combined constellation capacity of 320 Mbits will significantly exceed the capacity of any similar existing or currently planned global satellite system. In addition, the simplicity of the 4-satellite approach is the most cost effective means to deliver high bandwidth globally. Return links, which are required for internet service, will be provided through the existing Inmarsat Aero-H system already onboard virtually all long haul aircraft and will provide return data rates from the aircraft as high as 432 kbps. integrated receiver/decoder (IRD) assembly. The phased array antenna, a key technology element, is being developed by AirTV's strategic partner, CMC Electronics. This antenna is a scaled version of CMC's Inmarsat Aero H antenna and is capable of scanning to 5 degrees above the horizon. Wide angle scanning up to 85 degrees from zenith is necessary for aircraft traversing the northernmost latitudes on transoceanic routes. AirTV has designed both the satellite coverage and aircraft antenna performance to ensure that high signal quality is maintained along all non-polar airline routes. AirTV will be the future of aeronautical broadband delivery. It has been designed specifically for global services and uses the ideal spectrum for this application. It will revolutionize the delivery of content t

Sorbello, R.; Stone, R.; Bennett, S. B.; Bertenyi, E.

2002-01-01

332

Reducing Aviation's Environmental Impact Through Large Aircraft For Short Ranges  

E-print Network

- ever, the majority of aircraft used on these routes have design ranges considerably longer than 1 aircraft designed specifically for the majority of flights -- Large Aircraft for Short Ranges (LASR, a potential solution is Large Aircraft for Short Ranges (LASR). By designing aircraft for short ranges

Zingg, David W.

333

An aircraft sensor fault tolerant system  

NASA Technical Reports Server (NTRS)

The design of a sensor fault tolerant system which uses analytical redundancy for the Terminal Configured Vehicle (TCV) research aircraft in a Microwave Landing System (MLS) environment was studied. The fault tolerant system provides reliable estimates for aircraft position, velocity, and attitude in the presence of possible failures in navigation aid instruments and onboard sensors. The estimates, provided by the fault tolerant system, are used by the automated guidance and control system to land the aircraft along a prescribed path. Sensor failures are identified by utilizing the analytic relationship between the various sensor outputs arising from the aircraft equations of motion.

Caglayan, A. K.; Lancraft, R. E.

1982-01-01

334

14 CFR 93.155 - Aircraft operations.  

Code of Federal Regulations, 2010 CFR

...and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES SPECIAL AIR TRAFFIC RULES Ketchikan International Airport Traffic Rule § 93.155 Aircraft...

2010-01-01

335

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

336

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

337

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

338

Technical Seminar: "Progress in Aircraft Noise Research"""  

NASA Video Gallery

Advances in aircraft noise research can be attributed to the development of new technologies and sustained collaboration with industry, universities and government organizations. Emphasis has been ...

339

Fireworthiness of transport aircraft interior systems  

NASA Technical Reports Server (NTRS)

The fire worthiness of air transport interiors was evaluated. The effect of interior systems on the survival of passengers and crew in an uncontrolled transport aircraft fire is addressed. Modification of aircraft interior subsystem components which provide improvements in aircraft fire safety are examined. Three specific subsystem components, interior panels, seats and windows, offer the most immediate and highest payoff by modifying interior materials of existing aircrafts. It is shown that the new materials modifications reduce the fire hazards because of significant reduction in their characteristic flame spread, heat release, and smoke and toxic gas emissions.

Parker, J. A.; Kourtides, D. A.

1982-01-01

340

Aircraft mishap experience from atmospheric electricity hazards  

NASA Astrophysics Data System (ADS)

Aircraft mishaps resulting from inflight lightning strikes can range from inconsequential to catastrophic. A basic understanding of how lightning affects aircraft, based upon both military and commercial experience is established. Pilot reports of some representative incidents are described in detail, illustrating how the various atmospheric conditions and interaction mechanisms have affected aircraft operations. A summary of inflight mishap conditions is presented describing the range of flight circumstances under which aircraft are usually struck. The interaction of high current arcs with structural and external electrical hardware, the effects of electromagnetic coupling to interior avionics, and the effects of corona and high voltage sparking are also discussed.

Clifford, D. W.

1980-05-01

341

The lift-fan aircraft: Lessons learned  

NASA Technical Reports Server (NTRS)

This report summarizes the highlights and results of a workshop held at NASA Ames Research Center in October 1992. The objective of the workshop was a thorough review of the lessons learned from past research on lift fans, and lift-fan aircraft, models, designs, and components. The scope included conceptual design studies, wind tunnel investigations, propulsion systems components, piloted simulation, flight of aircraft such as the SV-5A and SV-5B and a recent lift-fan aircraft development project. The report includes a brief summary of five technical presentations that addressed the subject The Lift-Fan Aircraft: Lessons Learned.

Deckert, Wallace H.

1995-01-01

342

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

343

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

344

Commercial aircraft fuel efficiency potential through 2010  

SciTech Connect

Aircraft are second only to motor vehicles in the use of motor fuels, and air travel is growing twice as fast. Since 1970 air travel has more than tripled, but the growth of fuel use has been restrained by a near doubling of efficiency, from 26.2 seat miles per gallon (SMPG) in 1970 to about 49 SMPG in 1989. This paper explores the potential for future efficiency improvements via the replacement of existing aircraft with 1990's generation'' and post 2000'' aircraft incorporating advances in engine and airframe technology. Today, new commercial passenger aircraft deliver 50--70 SMPG. New aircraft types scheduled for delivery in the early 1990's are expected to achieve 65--80 SMPG. Industry and government researchers have identified technologies capable of boosting aircraft efficiencies to the 100--150 SMPG range. Under current industry plans, which do not include a post-2000 generation of new aircraft, the total aircraft fleet should reach the vicinity of 65 SMPG by 2010. A new generation of 100--150 SMPG aircraft introduced in 2005 could raise the fleet average efficiency to 75--80 SMPG in 2010. In any case, fuel use will likely continue to grow at from 1--2%/yr. through 2010. 20 refs., 2 figs., 2 tabs.

Greene, D.L.

1990-01-01

345

77 FR 44429 - Airworthiness Directives; Various Aircraft Equipped With Rotax Aircraft Engines 912 A Series Engine  

Federal Register 2010, 2011, 2012, 2013

...rgica Ltda. Diamond Aircraft Industries.... HK...DIMONA''. DIAMOND AIRCRAFT INDUSTRIES HK 36 TS and...912 A3 GmbH. Diamond Aircraft Industries DA20-A1...d) Subject Air Transport Association...hoses installed on the pressure side of P/N...

2012-07-30

346

Program to compute the positions of the aircraft and of the aircraft sensor footprints  

NASA Technical Reports Server (NTRS)

The positions of the ground track of the aircraft and of the aircraft sensor footprints, in particular the metric camera and the radar scatterometer on the C-130 aircraft, are estimated by a program called ACTRK. The program uses the altitude, speed, and attitude informaton contained in the radar scatterometer data files to calculate the positions. The ACTRK program is documented.

Paris, J. F. (principal investigator)

1982-01-01

347

Titanium fasteners. [for aircraft industry  

NASA Technical Reports Server (NTRS)

Titanium fasteners are used in large quantities throughout the aircraft industry. Most of this usage is in aluminum structure; where titanium structure exists, titanium fasteners are logically used as well. Titanium fasteners offer potential weight savings to the designer at a cost of approximately $30 per pound of weight saved. Proper and least cost usage must take into consideration type of fastener per application, galvanic couples and installation characteristics of protective coatings, cosmetic appearance, paint adhesion, installation forces and methods available and fatigue performance required.

Phillips, J. L.

1972-01-01

348

Altus I aircraft on lakebed  

NASA Technical Reports Server (NTRS)

The remotely-piloted Altus I aircraft climbs away after takeoff from Rogers Dry Lake adjacent to NASA's Dryden Flight Research Center, Edwards, Calif. The short series of test flights sponsored by the Naval Postgraduate School in early August, 1997, were designed to demonstrate the ability of the experimental craft to cruise at altitudes above 40,000 feet for sustained durations. On its final flight Aug. 15, the Altus I reached an altitude of 43,500 feet. The Altus I and its sister ship, the Altus II, are variants of the Predator surveillance drone built by General Atomics/Aeronautical Systems, Inc. They are designed for high-altitude, long-duration scientific sampling missions, and are powered by turbocharged piston engines. The Altus I incorporates a single-stage turbocharger, while the Altus II, built for NASA's Environmental Research Aircraft and Sensor Technology program, sports a two-stage turbocharger to enable the craft to fly at altitudes above 55,000 feet. The Altus II, the first of the two craft to be completed, made its first flight on May 1, 1996. With its engine augmented by a single-stage turbocharger, the Altus II reached an altitude of 37,000 ft during its first series of development flights at Dryden in Aug., 1996. In Oct. of that year, the Altus II was flown in an Atmospheric Radiation Measurement study for the Department of Energy's Sandia National Laboratory in Oklahoma. During the course of those flights, the Altus II set a single-flight endurance record for remotely-operated aircraft of more than 26 hours. The Altus I, completed in 1997, flew a series of development flights at Dryden that summer. Those test flights culminated with the craft reaching an altitude of 43,500 ft while carrying a simulated 300-lb payload, a record for an unmanned aircraft powered by a piston engine augmented with a single-stage turbocharger. The Altus II sustained an altitudeof 55,000 feet for four hours in 1999. A pilot in a control station on the ground flies the craft by radio signals, using visual cues from a video camera in the nose of the Altus and information from the craft's air data system.

1997-01-01

349

Combustor technology for future aircraft  

NASA Technical Reports Server (NTRS)

The continuing improvement of aircraft gas turbine engine operating efficiencies involves increases in overall engine pressure ratio increases that will result in combustor inlet pressure and temperature increases, greater combustion temperature rises, and higher combustor exit temperatures. These conditions entail the development of fuel injectors generating uniform circumferential and radial temperature patterns, as well as combustor liner configurations and materials capable of withstanding increased thermal radiation even as the amount of cooling air is reduced. Low NO(x)-emitting combustor concepts are required which will employ staged combustion. The development status of component technologies answering these requirements are presently evaluated.

Tacina, Robert R.

1990-01-01

350

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

351

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

352

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

353

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

354

Community noise exposure resulting from aircraft operations. Volume 2: Acoustic data on military aircraft, Air Force bomber\\/cargo aircraft  

Microsoft Academic Search

This report presents the results of field test measurements to define the single event noise produced on the ground by military, fixed wing aircraft during controlled level flyovers and ground runups. For flight conditions, data are presented in terms of various acoustic measures over the range 200-25,000 feet minimum slant distance to the aircraft. For ground runups, data are presented

J. D. Speakman; R. G. Powell; R. A. Lee

1977-01-01

355

14 CFR 252.11 - Aircraft on the ground.  

...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...

2014-01-01

356

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

357

14 CFR 252.11 - Aircraft on the ground.  

Code of Federal Regulations, 2013 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...

2013-01-01

358

14 CFR 252.11 - Aircraft on the ground.  

Code of Federal Regulations, 2012 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...

2012-01-01

359

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

360

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

361

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

362

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

363

78 FR 14726 - Airworthiness Directives; Cessna Aircraft Company Airplanes  

Federal Register 2010, 2011, 2012, 2013

...054 engine oil pressure switch and hour...flight of civil aircraft in air commerce by prescribing...applies to Cessna Aircraft Company Models...Subject Joint Aircraft System Component (JASC)/Air Transport Association...Engine Oil Pressure. (e)...

2013-03-07

364

The dynamic scheduling of aircraft in the near terminal area  

E-print Network

Aircraft arrive in a random fashion into a terminal area seeking to land at a given runway. The aircraft are differentiated by their landing velocities. All aircraft are required to maintain a prespecified minimum horizontal ...

Dear, Roger George

1976-01-01

365

77 FR 68058 - Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters  

Federal Register 2010, 2011, 2012, 2013

...this AD, contact Sikorsky Aircraft Corporation, Attn: Manager...Test Engineer, Boston Aircraft Certification Office...products of these same type designs. Related Service Information We reviewed Sikorsky Aircraft Corporation Alert...

2012-11-15

366

Stochastic Gust Analysis Techniques for Aircraft Conceptual Design  

E-print Network

Stochastic Gust Analysis Techniques for Aircraft Conceptual Design Krzysztof J. Fidkowski , Frode are an important design consideration for novel aircraft configurations. Incorporating these constraints constraints due to maneuver and gust loads, which are an important design consideration for novel aircraft

Stanford University

367

Nonlinear Gust Response of Highly Flexible Aircraft Mayuresh J. Patil,  

E-print Network

and design of very light, and thus highly flexible, aircraft configurations is of interest estimation of a highly flexible aircraft. Various realistic design space requirements including, concentratedNonlinear Gust Response of Highly Flexible Aircraft Mayuresh J. Patil, Virginia Polytechnic

Patil, Mayuresh

368

14 CFR 121.157 - Aircraft certification and equipment requirements.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Aircraft certification and equipment...AND SUPPLEMENTAL OPERATIONS Aircraft Requirements § 121.157 Aircraft certification and equipment...considering the effect of design changes) compliance is...

2013-01-01

369

14 CFR 121.153 - Aircraft requirements: General.  

Code of Federal Regulations, 2011 CFR

...Aviation if— (1) The aircraft carries an appropriate...country; (2) The aircraft is of a type design which is approved...be applicable to that aircraft were it registered...certificate (including type design conformity,...

2011-01-01

370

14 CFR 121.157 - Aircraft certification and equipment requirements.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 false Aircraft certification and equipment...AND SUPPLEMENTAL OPERATIONS Aircraft Requirements § 121.157 Aircraft certification and equipment...considering the effect of design changes) compliance is...

2011-01-01

371

14 CFR 121.153 - Aircraft requirements: General.  

Code of Federal Regulations, 2013 CFR

...Aviation if— (1) The aircraft carries an appropriate...country; (2) The aircraft is of a type design which is approved...be applicable to that aircraft were it registered...certificate (including type design conformity,...

2013-01-01

372

50 years of transonic aircraft design Antony Jameson, Kui Ou  

E-print Network

50 years of transonic aircraft design Antony Jameson, Kui Ou Ã? Aeronautics and Astronautics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 5. Other aspects of aircraft design range jet transport aircraft over the 50 years since Kuechemann founded the journal Progress

Jameson, Antony

373

14 CFR 121.157 - Aircraft certification and equipment requirements.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 false Aircraft certification and equipment...AND SUPPLEMENTAL OPERATIONS Aircraft Requirements § 121.157 Aircraft certification and equipment...considering the effect of design changes) compliance is...

2010-01-01

374

14 CFR 121.157 - Aircraft certification and equipment requirements.  

Code of Federal Regulations, 2012 CFR

... 2012-01-01 false Aircraft certification and equipment...AND SUPPLEMENTAL OPERATIONS Aircraft Requirements § 121.157 Aircraft certification and equipment...considering the effect of design changes) compliance is...

2012-01-01

375

14 CFR 121.153 - Aircraft requirements: General.  

...Aviation if— (1) The aircraft carries an appropriate...country; (2) The aircraft is of a type design which is approved...be applicable to that aircraft were it registered...certificate (including type design conformity,...

2014-01-01

376

14 CFR 121.157 - Aircraft certification and equipment requirements.  

... 2014-01-01 false Aircraft certification and equipment...AND SUPPLEMENTAL OPERATIONS Aircraft Requirements § 121.157 Aircraft certification and equipment...considering the effect of design changes) compliance is...

2014-01-01

377

14 CFR 36.13 - Acoustical change: Tiltrotor aircraft.  

...DEPARTMENT OF TRANSPORTATION AIRCRAFT NOISE STANDARDS: AIRCRAFT TYPE AND AIRWORTHINESS CERTIFICATION...Acoustical change: Tiltrotor aircraft. The following requirements...c) After a change in type design, tiltrotor noise levels...

2014-01-01

378

14 CFR 121.153 - Aircraft requirements: General.  

Code of Federal Regulations, 2010 CFR

...Aviation if— (1) The aircraft carries an appropriate...country; (2) The aircraft is of a type design which is approved...be applicable to that aircraft were it registered...certificate (including type design conformity,...

2010-01-01

379

14 CFR 121.153 - Aircraft requirements: General.  

Code of Federal Regulations, 2012 CFR

...Aviation if— (1) The aircraft carries an appropriate...country; (2) The aircraft is of a type design which is approved...be applicable to that aircraft were it registered...certificate (including type design conformity,...

2012-01-01

380

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

381

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

382

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.

383

19 CFR 122.41 - Aircraft required to enter.  

Code of Federal Regulations, 2011 CFR

... Aircraft Entry and Entry Documents; Electronic Manifest Requirements for Passengers, Crew Members, and Non-Crew Members Onboard Commercial Aircraft Arriving In, Continuing Within, and Overflying the United States § 122.41 Aircraft required...

2011-04-01

384

19 CFR 122.41 - Aircraft required to enter.  

... Aircraft Entry and Entry Documents; Electronic Manifest Requirements for Passengers, Crew Members, and Non-Crew Members Onboard Commercial Aircraft Arriving In, Continuing Within, and Overflying the United States § 122.41 Aircraft required...

2014-04-01

385

19 CFR 122.41 - Aircraft required to enter.  

Code of Federal Regulations, 2013 CFR

... Aircraft Entry and Entry Documents; Electronic Manifest Requirements for Passengers, Crew Members, and Non-Crew Members Onboard Commercial Aircraft Arriving In, Continuing Within, and Overflying the United States § 122.41 Aircraft required...

2013-04-01

386

19 CFR 122.41 - Aircraft required to enter.  

Code of Federal Regulations, 2010 CFR

... Aircraft Entry and Entry Documents; Electronic Manifest Requirements for Passengers, Crew Members, and Non-Crew Members Onboard Commercial Aircraft Arriving In, Continuing Within, and Overflying the United States § 122.41 Aircraft required...

2010-04-01

387

19 CFR 122.41 - Aircraft required to enter.  

Code of Federal Regulations, 2012 CFR

... Aircraft Entry and Entry Documents; Electronic Manifest Requirements for Passengers, Crew Members, and Non-Crew Members Onboard Commercial Aircraft Arriving In, Continuing Within, and Overflying the United States § 122.41 Aircraft required...

2012-04-01

388

78 FR 9796 - Airworthiness Directives; Cessna Aircraft Company Airplanes  

Federal Register 2010, 2011, 2012, 2013

...contact Cessna Aircraft Company, Customer service, P.O...effect on the States, on the relationship between the national government...2013-03-15 Cessna Aircraft Company: Amendment 39-17350; Docket...following Cessna Aircraft Company (Cessna) airplanes,...

2013-02-12

389

19 CFR 122.132 - Sealing of aircraft liquor kits.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 false Sealing of aircraft liquor kits. 122.132 Section 122.132 Customs...TREASURY AIR COMMERCE REGULATIONS Aircraft Liquor Kits § 122.132 Sealing of aircraft liquor kits. (a) Sealing required....

2011-04-01

390

19 CFR 122.132 - Sealing of aircraft liquor kits.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Sealing of aircraft liquor kits. 122.132 Section 122.132 Customs...TREASURY AIR COMMERCE REGULATIONS Aircraft Liquor Kits § 122.132 Sealing of aircraft liquor kits. (a) Sealing required....

2010-04-01

391

19 CFR 122.132 - Sealing of aircraft liquor kits.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Sealing of aircraft liquor kits. 122.132 Section 122.132 Customs...TREASURY AIR COMMERCE REGULATIONS Aircraft Liquor Kits § 122.132 Sealing of aircraft liquor kits. (a) Sealing required....

2013-04-01

392

19 CFR 122.132 - Sealing of aircraft liquor kits.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 false Sealing of aircraft liquor kits. 122.132 Section 122.132 Customs...TREASURY AIR COMMERCE REGULATIONS Aircraft Liquor Kits § 122.132 Sealing of aircraft liquor kits. (a) Sealing required....

2012-04-01

393

64 FR 18652 - Design Approval of Aircraft Data Communications Systems  

Federal Register 2010, 2011, 2012, 2013

...Communication Systems. The proposed...of aircraft data communication systems and applications...Aircraft Engineering Division...Aircraft Engineering Division, Avionic Systems Branch, AIR-130...such written data, views,...

1999-04-15

394

14 CFR 91.1109 - Aircraft maintenance: Inspection program.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 false Aircraft maintenance: Inspection program. 91...Management § 91.1109 Aircraft maintenance: Inspection program. Each...program manager must establish an aircraft inspection program for...

2011-01-01

395

77 FR 59146 - Airworthiness Directives; Cessna Aircraft Company Airplanes  

Federal Register 2010, 2011, 2012, 2013

...proposed AD, contact Cessna Aircraft Co., P.O. Box 7706...ACE-119W, FAA, Wichita Aircraft Certification Office (ACO...in the tailcone of Cessna Aircraft Company Model 525, 550...Model 550, -0801 and On Maintenance Manual. Subject...

2012-09-26

396

14 CFR 183.27 - Designated aircraft maintenance inspectors.  

...2014-01-01 false Designated aircraft maintenance inspectors. 183.27 Section...Privileges § 183.27 Designated aircraft maintenance inspectors. A designated aircraft maintenance inspector (DAMI) may approve...

2014-01-01

397

14 CFR 183.27 - Designated aircraft maintenance inspectors.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 false Designated aircraft maintenance inspectors. 183.27 Section...Privileges § 183.27 Designated aircraft maintenance inspectors. A designated aircraft maintenance inspector (DAMI) may approve...

2013-01-01

398

14 CFR 91.1109 - Aircraft maintenance: Inspection program.  

... 2014-01-01 false Aircraft maintenance: Inspection program. 91...Management § 91.1109 Aircraft maintenance: Inspection program. Each...program manager must establish an aircraft inspection program for...

2014-01-01

399

14 CFR 91.1109 - Aircraft maintenance: Inspection program.  

Code of Federal Regulations, 2012 CFR

... 2012-01-01 false Aircraft maintenance: Inspection program. 91...Management § 91.1109 Aircraft maintenance: Inspection program. Each...program manager must establish an aircraft inspection program for...

2012-01-01

400

78 FR 24343 - Airworthiness Directives; Cessna Aircraft Company Airplanes  

Federal Register 2010, 2011, 2012, 2013

...23, 2012, of Cessna Aircraft Company Model 525 Maintenance Manual, Revision 23...23, 2012, of Cessna Aircraft Company Model 525 Maintenance Manual, Revision 23...Reserved. (3) For Cessna Aircraft Company service...

2013-04-25

401

14 CFR 183.27 - Designated aircraft maintenance inspectors.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 false Designated aircraft maintenance inspectors. 183.27 Section...Privileges § 183.27 Designated aircraft maintenance inspectors. A designated aircraft maintenance inspector (DAMI) may approve...

2010-01-01

402

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

Federal Register 2010, 2011, 2012, 2013

...ALS) of the Aircraft Maintenance Manual (AMM...documents include the maintenance instructions and...developed by Pilatus Aircraft Ltd. and approved...Information PILATUS Aircraft Ltd. has issued PILATUS PC-7 Maintenance Manual,...

2013-04-26

403

14 CFR 183.27 - Designated aircraft maintenance inspectors.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 false Designated aircraft maintenance inspectors. 183.27 Section...Privileges § 183.27 Designated aircraft maintenance inspectors. A designated aircraft maintenance inspector (DAMI) may approve...

2011-01-01

404

14 CFR 91.1109 - Aircraft maintenance: Inspection program.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 false Aircraft maintenance: Inspection program. 91...Management § 91.1109 Aircraft maintenance: Inspection program. Each...program manager must establish an aircraft inspection program for...

2010-01-01

405

14 CFR 183.27 - Designated aircraft maintenance inspectors.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 false Designated aircraft maintenance inspectors. 183.27 Section...Privileges § 183.27 Designated aircraft maintenance inspectors. A designated aircraft maintenance inspector (DAMI) may approve...

2012-01-01

406

14 CFR 91.1109 - Aircraft maintenance: Inspection program.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Aircraft maintenance: Inspection program. 91...Management § 91.1109 Aircraft maintenance: Inspection program. Each...program manager must establish an aircraft inspection program for...

2013-01-01

407

17 CFR 256.310 - Aircraft and airport equipment.  

Code of Federal Regulations, 2011 CFR

...Property Accounts § 256.310 Aircraft and airport equipment. ...all service company owned aircraft and accessories thereto...equipment used in the inspection, maintenance, repair and overhaul of aircraft shall also be included...

2011-04-01

408

14 CFR 65.70 - Aircraft dispatcher certification courses: Records.  

Code of Federal Regulations, 2011 CFR

...false Aircraft dispatcher certification courses: Records. 65.70 Section 65.70...70 Aircraft dispatcher certification courses: Records. (a) The operator of an aircraft dispatcher course must maintain a record for each...

2011-01-01

409

14 CFR 65.67 - Aircraft dispatcher certification courses: Personnel.  

Code of Federal Regulations, 2011 CFR

...false Aircraft dispatcher certification courses: Personnel. 65.67 Section 65...67 Aircraft dispatcher certification courses: Personnel. (a) Each applicant for an aircraft dispatcher certification course must meet the following personnel...

2011-01-01

410

14 CFR 65.67 - Aircraft dispatcher certification courses: Personnel.  

Code of Federal Regulations, 2010 CFR

...false Aircraft dispatcher certification courses: Personnel. 65.67 Section 65...67 Aircraft dispatcher certification courses: Personnel. (a) Each applicant for an aircraft dispatcher certification course must meet the following personnel...

2010-01-01

411

14 CFR 65.67 - Aircraft dispatcher certification courses: Personnel.  

Code of Federal Regulations, 2012 CFR

...false Aircraft dispatcher certification courses: Personnel. 65.67 Section 65...67 Aircraft dispatcher certification courses: Personnel. (a) Each applicant for an aircraft dispatcher certification course must meet the following personnel...

2012-01-01

412

14 CFR 65.70 - Aircraft dispatcher certification courses: Records.  

Code of Federal Regulations, 2012 CFR

...false Aircraft dispatcher certification courses: Records. 65.70 Section 65.70...70 Aircraft dispatcher certification courses: Records. (a) The operator of an aircraft dispatcher course must maintain a record for each...

2012-01-01

413

14 CFR 65.70 - Aircraft dispatcher certification courses: Records.  

Code of Federal Regulations, 2013 CFR

...false Aircraft dispatcher certification courses: Records. 65.70 Section 65.70...70 Aircraft dispatcher certification courses: Records. (a) The operator of an aircraft dispatcher course must maintain a record for each...

2013-01-01

414

14 CFR 65.67 - Aircraft dispatcher certification courses: Personnel.  

Code of Federal Regulations, 2013 CFR

...false Aircraft dispatcher certification courses: Personnel. 65.67 Section 65...67 Aircraft dispatcher certification courses: Personnel. (a) Each applicant for an aircraft dispatcher certification course must meet the following personnel...

2013-01-01

415

14 CFR 65.70 - Aircraft dispatcher certification courses: Records.  

Code of Federal Regulations, 2010 CFR

...false Aircraft dispatcher certification courses: Records. 65.70 Section 65.70...70 Aircraft dispatcher certification courses: Records. (a) The operator of an aircraft dispatcher course must maintain a record for each...

2010-01-01

416

NASA's Quiet Aircraft Technology Project  

NASA Technical Reports Server (NTRS)

NASA's Quiet Aircraft Technology Project is developing physics-based understanding, models and concepts to discover and realize technology that will, when implemented, achieve the goals of a reduction of one-half in perceived community noise (relative to 1997) by 2007 and a further one-half in the far term. Noise sources generated by both the engine and the airframe are considered, and the effects of engine/airframe integration are accounted for through the propulsion airframe aeroacoustics element. Assessments of the contribution of individual source noise reductions to the reduction in community noise are developed to guide the work and the development of new tools for evaluation of unconventional aircraft is underway. Life in the real world is taken into account with the development of more accurate airport noise models and flight guidance methodology, and in addition, technology is being developed that will further reduce interior noise at current weight levels or enable the use of lighter-weight structures at current noise levels.

Whitfield, Charlotte E.

2004-01-01

417

Aircraft Landing Dynamics Facility (ALDF)  

NASA Technical Reports Server (NTRS)

Original Test Carriage: A carriage catapulted by a hydraulic jet at speeds up to 150 mph for studies of ground loads on high-speed aircraft is in operation at the Langley Research Center of the National Aeronautics and Space Administration. A drop test rig is installed on the carriage, which is catapulted 400 feet in 3.5 seconds. The carriage travels along a track and special instruments record loads data as an aircraft landing gear or other test specimen is dropped on a concrete strip. Five cables attached to a battery of 20 Navy Mark IV arresting gears, stretched across the 2,200-foot track, bring the carriage to a halt after the test run. The carriage, when loaded to its capacity of 20,000 pounds, represents a 50-ton load. The hydraulic catapult consists of a single water jet, which roars from a nozzle at the front end of the L-shaped pressure vessel (center) and is forced into a specially-shaped bucket on the carriage. The water jet, traveling at 660 feet per second, undergoes a 180 degree change of direction and floods out of another opening in the bucket below the incoming jet stream. The momentum change produces a thrust on the carriage of 400,00 pounds.

1964-01-01

418

Vision-based aircraft guidance  

NASA Technical Reports Server (NTRS)

Early research on the development of machine vision algorithms to serve as pilot aids in aircraft flight operations is discussed. The research is useful for synthesizing new cockpit instrumentation that can enhance flight safety and efficiency. With the present work as the basis, future research will produce low-cost instrument by integrating a conventional TV camera together with off-the=shelf digitizing hardware for flight test verification. Initial focus of the research will be on developing pilot aids for clear-night operations. Latter part of the research will examine synthetic vision issues for poor visibility flight operations. Both research efforts will contribute towards the high-speed civil transport aircraft program. It is anticipated that the research reported here will also produce pilot aids for conducting helicopter flight operations during emergency search and rescue. The primary emphasis of the present research effort is on near-term, flight demonstrable technologies. This report discusses pilot aids for night landing and takeoff and synthetic vision as an aid to low visibility landing.

Menon, P. K.

1993-01-01

419

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

420

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

421

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

422

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

423

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

424

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

425

THE IMPACT OF WEATHER ON AIRCRAFTS ACCIDENTS  

Microsoft Academic Search

For any aircraft accident, the first suspected cause is weather until thorough investigations reveal the true cause. Indeed different weather events pose various hazards on aircrafts significantly. Since the commercialization of some of the services rendered by the South African Weather Services (SAWS) such as the aviation weather products, there is a greater need for SAWS aviation weather forecasters to

Rudzani Malala; South African Weather Service

426

NASA Langley's Aircraft Landing Dynamics Facility  

NASA Technical Reports Server (NTRS)

The Aircraft Landing Dynamics Facility (ALDF) is a unique facility with the ability to test aircraft landing gear systems on actual runway surfaces at operational ground speeds and loading conditions. A brief historical overview of the original Landing Loads Track (LLT) is given, followed by a detailed description of the new ALDF systems and operational capabilities.

Davis, Pamela A.

1993-01-01

427

Computational Aerodynamics for Aircraft Design Antony Jameson  

E-print Network

Computational Aerodynamics for Aircraft Design Antony Jameson Abstract This article outlines some to optimize the aerodynamic performance. While computational methods for simulating fluid flow have by now to design more efficient aircraft. One route toward this goal is more precise aerodynamic design

Jameson, Antony

428

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.

429

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

430

Virtual Collaboration Environment for Aircraft Design  

Microsoft Academic Search

This paper presents a virtual collaboration environment for aircraft design. The presented system, abbreviated as VCEAD, provides virtual prototyping and communication features for synchronous collaboration between geographically distributed designers. Concurrent design reviews on large scale objects, such as aircraft fuselage, are possible over distance due to the technological choices of the system. These include XML, VRML and Java based solutions

Markus D. Durstewitz; Bernhard Kiefner; Reimund Kueke; Heikki Putkonen; Pertti Repo; Tuomo Tuikka

2002-01-01

431

Parallel Global Aircraft Configuration Design Space Exploration  

E-print Network

Parallel Global Aircraft Configuration Design Space Exploration CHUCK A. BAKER, LAYNE T. WATSON of a parallel computer. Section 2 describes the aircraft design problem, Section 3 gives the direct search, BERNARD GROSSMAN, WILLIAM H. MASON Multidisciplinary Analysis and Design (MAD) Center for Advanced

Neumaier, Arnold

432

New realities in aircraft design and manufacture  

Microsoft Academic Search

Considers how Boeing Computer Services in Seattle is developing two real-time applications-one in virtual reality, the other in what the company calls augmented reality, aimed at putting more information directly in front of the engineers designing aircraft and the manufacturing workers who build them. Boeing's virtual reality project plans to import aircraft CAD data to a VR environment where engineers

D. Sims

1994-01-01

433

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

434

Advanced Aircraft Secondary Power System Design  

Microsoft Academic Search

This paper describes the requirements, the secondary power system design, and the results of a trade study for an Advanced Aircraft Secondary Power System Design (AASPSD). AASPSD is an Air Force funded contract performed by The Boeing Company. The aircraft selected for this study was a Mach 6 vehicle. The three AASPSD configurations studied were a conventional system having hydraulic

E. J. Woods; C. S. Rubertus; I. S. Mehdi

1990-01-01

435

Parametric geometry representation to support aircraft design  

Microsoft Academic Search

Knowledge Based Engineering (KBE) plays an important role in automation and optimization of the aircraft design process. But the lack of real KBE tools limits the promise of Knowledge Based Engineering. To address this deficiency, we propose using the Python programming language to develop viable KBE application tools for aircraft design. Selecting geometric parameterization algorithms is fundamental to automation and

Marcos Elgueta Soulat

2012-01-01

436

Measurement of In-Flight Aircraft Emissions  

NASA Technical Reports Server (NTRS)

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

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

1995-01-01

437

Measurements of Lightning Strikes to Aircraft.  

National Technical Information Service (NTIS)

Sandia's primary interest in a joint thunderstorm research effort was in the effect of lightning on nuclear weapons and on aircraft and missile wiring. A description of the test instrumentation, its installation in the aircraft, and an analysis of the res...

B. J. Petterson, W. R. Wood

1968-01-01

438

Nondestructive visual inspection of aging aircraft  

Microsoft Academic Search

The in-flight structural failure of an Aloha Airlines 737-200 in April of 1988 brought international attention to the aging aircraft issue and prompted operators to improve inspection and maintenance procedures for their fleets. The use of nondestructive visual inspection equipment such as borescopes, fiberscopes, and videoimagescopes allow maintenance personnel to inspect internal aircraft structure for corrosion and fatigue without costly

Peter Samsonov

1995-01-01

439

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

440

Remote Inspection Technologies for Aircraft Skin Inspection  

Microsoft Academic Search

Aircraft flight pressurization\\/depressurization cycles cause their skins to inflate and deflate, stressing the skin around the rivets that fasten it to the airframe. The resulting strain, exacerbated by any corrosion that might be present, drives the growth of the initially microscopic cracks that are an unavoidable by-product of rivet installation. To avoid catastrophe, aircraft are periodically inspected for cracks and

Mel Siegel; Priyan Gunatilake

1997-01-01

441

Laminar flow control for transport aircraft applications  

NASA Technical Reports Server (NTRS)

The incorporation of laminar flow control into transport aircraft is discussed. Design concepts for the wing surface panel of laminar flow control transport aircraft are described. The development of small amounts of laminar flow on small commercial transports with natural or hybrid flow control is examined. Techniques for eliminating the insect contamination problem in the leading-edge region are proposed.

Wagner, R. D.

1986-01-01

442

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

443

WEATHER MODIFICATION BY AIRCRAFT CLOUD SEEDING  

E-print Network

WEATHER MODIFICATION BY AIRCRAFT CLOUD SEEDING BERYULEV G.P. Head, Department of Cloud;#12; Precipitation Enhancement An aircraft cloud seeding by iceforming or hygroscopic agents is a basis of atmosphere and clouds necessary for decision making, fulfillment of seeding and assessment

Vali, Gabor

444

Pneumatic system structure for circulation control aircraft  

NASA Technical Reports Server (NTRS)

A plenum for a circulation control rotor aircraft which surrounds the rotor drive shaft (18) and is so constructed that the top (32), outer (38) and bottom (36) walls through compressed air is admitted are fixed to aircraft structure and the inner wall (34) through which air passes to rotor blades (14) rotates with the drive shaft and rotor blades.

Krauss, Timothy A. (Inventor); Roman, Stephan (Inventor); Beurer, Robert J. (Inventor)

1986-01-01

445

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

446

A Ubiquitous Computing environment for aircraft maintenance  

Microsoft Academic Search

Ubiquitous Computing bears a high potential in the area of aircraft maintenance. Extensive requirements regarding quality, safety, and documentation as well as high costs for having aircrafts idle during maintenance demand for an efficient execution of the process. Major weaknesses that impact the efficiency of the process are an inadequate tool management, human erros, and labour intensive manual documentation and

Matthias Lampe; Martin Strassner; Elgar Fleisch

2004-01-01

447

Optimum Integration of Aircraft Navigation Systems  

Microsoft Academic Search

A current problem in aircraft navigation is determining how to effect alow cost navigation system consistent with required mission operationswhich will render a high degree of accuracy and reliability. One wayto achieve this is through optimum integration of equipment,subsystems, and computer mechanizations. Consistent with this approach,the overall objectives of this paper are to show the advantages of anoptimally integrated aircraft

William Zimmerman

1969-01-01

448

MULTI AIRCRAFT DYNAMICS, NAVIGATION AND OPERATION  

E-print Network

MULTI AIRCRAFT DYNAMICS, NAVIGATION AND OPERATION A DISSERTATION SUBMITTED TO THE DEPARTMENT navigation systems, and air-to-air data links are the technical keys to this revolution. Many airports tackles the problem of multi aircraft dynamics, navigation, and operation, specifically in the terminal

Stanford University

449

14 CFR 91.117 - Aircraft speed.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 2011-01-01 false Aircraft speed. 91.117 Section 91.117 Aeronautics...Rules General § 91.117 Aircraft speed. (a) Unless otherwise authorized...particular operation is greater than the maximum speed prescribed in this section, the...

2011-01-01

450

14 CFR 91.117 - Aircraft speed.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Aircraft speed. 91.117 Section 91.117 Aeronautics...Rules General § 91.117 Aircraft speed. (a) Unless otherwise authorized...particular operation is greater than the maximum speed prescribed in this section, the...

2010-01-01

451

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

452

Aircraft measurements and coordination in FASINEX  

NASA Astrophysics Data System (ADS)

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 Atmospheric Research (NCAR), Boulder, Colorado and shipped to NRL and made operational in the laboratory; (c) various environmental sensors obtained from USN China Lake, CA, for the NRL RP3A: Barnes infrared meterological radiometers; parts of dew point system; (2) FASINEX Aircraft Coordination: (a) site visit made to NAS Bermuda, facilities will be provided for transient FASINEX aircraft by NAS Bermuda; (b) cooperative agreement for joint use of NCAR Electra research aircraft by GALE and FASINEX projects worked out; (c) attended GALE planning meeting as FASINEX representative.

Friehe, C.

1985-07-01

453

Flux Sampling Errors for Aircraft and Towers  

NASA Technical Reports Server (NTRS)

Various errors and influences leading to differences between tower- and aircraft-measured fluxes are surveyed. This survey is motivated by reports in the literature that aircraft fluxes are sometimes smaller than tower-measured fluxes. Both tower and aircraft flux errors are larger with surface heterogeneity due to several independent effects. Surface heterogeneity may cause tower flux errors to increase with decreasing wind speed. Techniques to assess flux sampling error are reviewed. Such error estimates suffer various degrees of inapplicability in real geophysical time series due to nonstationarity of tower time series (or inhomogeneity of aircraft data). A new measure for nonstationarity is developed that eliminates assumptions on the form of the nonstationarity inherent in previous methods. When this nonstationarity measure becomes large, the surface energy imbalance increases sharply. Finally, strategies for obtaining adequate flux sampling using repeated aircraft passes and grid patterns are outlined.

Mahrt, Larry

1998-01-01

454

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

455

Small Aircraft RF Interference Path Loss Measurements  

NASA Technical Reports Server (NTRS)

Interference to aircraft radio receivers is an increasing concern as more portable electronic devices are allowed onboard. Interference signals are attenuated as they propagate from inside the cabin to aircraft radio antennas mounted on the outside of the aircraft. The attenuation level is referred to as the interference path loss (IPL) value. Significant published IPL data exists for transport and regional category airplanes. This report fills a void by providing data for small business/corporate and general aviation aircraft. In this effort, IPL measurements are performed on ten small aircraft of different designs and manufacturers. Multiple radio systems are addressed. Along with the typical worst-case coupling values, statistical distributions are also reported that could lead to more meaningful interference risk assessment.

Nguyen, Truong X.; Koppen, Sandra V.; Ely, Jay J.; Szatkowski, George N.; Mielnik, John J.; Salud, Maria Theresa P.

2007-01-01

456

Scorpion: Close Air Support (CAS) aircraft  

NASA Technical Reports Server (NTRS)

The objective is to outline the results of the preliminary design of the Scorpion, a proposed close air support aircraft. The results obtained include complete preliminary analysis of the aircraft in the areas of aerodynamics, structures, avionics and electronics, stability and control, weight and balance, propulsion systems, and costs. A conventional wing, twin jet, twin-tail aircraft was chosen to maximize the desirable characteristics. The Scorpion will feature low speed maneuverability, high survivability, low cost, and low maintenance. The life cycle cost per aircraft will be 17.5 million dollars. The maximum takeoff weight will be 52,760 pounds. Wing loading will be 90 psf. The thrust to weight will be 0.6 lbs/lb. This aircraft meets the specified mission requirements. Some modifications have been suggested to further optimize the design.

Allen, Chris; Cheng, Rendy; Koehler, Grant; Lyon, Sean; Paguio, Cecilia

1991-01-01

457

Small Aircraft RF Interference Path Loss  

NASA Technical Reports Server (NTRS)

Interference to aircraft radio receivers is an increasing concern as more portable electronic devices are allowed onboard. Interference signals are attenuated as they propagate from inside the cabin to aircraft radio antennas mounted on the outside of the aircraft. The attenuation level is referred to as the interference path loss (IPL) value. Significant published IPL data exists for transport and regional category airplanes. This report fills a void by providing data for small business/corporate and general aviation aircraft. In this effort, IPL measurements are performed on ten small aircraft of different designs and manufacturers. Multiple radio systems are addressed. Along with the typical worst-case coupling values, statistical distributions are also reported that could lead to better interference risk assessment.

Nguyen, Truong X.; Koppen, Sandra V.; Ely, Jay J.; Szatkowski, George N.; Mielnik, John J.; Salud, Maria Theresa P.

2007-01-01

458

GaAs/Ge Solar Powered Aircraft  

NASA Technical Reports Server (NTRS)

Unmanned Aerial Vehicles (UAV) are being proposed for many applications for many applications including surveillance, mapping and atmospheric studies. These applications require a lightweight, low speed, medium to long duration aircraft. Due to the weight, speed, and altitude constraints imposed on such an aircraft, solar array generated electric power can be a viable alternative to air-breathing engines for certain missions. Development of such an aircraft is currently being funded under the Environmental Research Aircraft and Sensor Technology (ERAST) program. NASA Lewis Research Center (LeRC) has built a Solar Electric Airplane to demonstrate UAV technology. This aircraft utilizes high efficiency Applied Solar Energy Corporation (ASEC) GaAs/Ge space solar cells. The cells have been provided by the Air Force through the ManTech Office.

Colozza, Anthony J.; Scheiman, David A.; Brinker, David J.

1998-01-01

459

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

460

High Energy Wide Area Blunt Impact on Composite Aircraft Structures /  

E-print Network

while the aircraft is receiving maintenance. FOD can lift upaircraft, flight overload conditions, abnormally hard landings, and maintenancemaintenance equipment or other unattended GSE blown into the aircraft,

DeFrancisci, Gabriela K.

2013-01-01

461

PIK-20 Aircraft in Flight  

NASA Technical Reports Server (NTRS)

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

1991-01-01

462

Mortality among aircraft manufacturing workers  

PubMed Central

OBJECTIVES: To evaluate the risk of cancer and other diseases among workers engaged in aircraft manufacturing and potentially exposed to compounds containing chromate, trichloroethylene (TCE), perchloroethylene (PCE), and mixed solvents. METHODS: A retrospective cohort mortality study was conducted of workers employed for at least 1 year at a large aircraft manufacturing facility in California on or after 1 January 1960. The mortality experience of these workers was determined by examination of national, state, and company records to the end of 1996. Standardised mortality ratios (SMRs) were evaluated comparing the observed numbers of deaths among workers with those expected in the general population adjusting for age, sex, race, and calendar year. The SMRs for 40 cause of death categories were computed for the total cohort and for subgroups defined by sex, race, position in the factory, work duration, year of first employment, latency, and broad occupational groups. Factory job titles were classified as to likely use of chemicals, and internal Poisson regression analyses were used to compute mortality risk ratios for categories of years of exposure to chromate, TCE, PCE, and mixed solvents, with unexposed factory workers serving as referents. RESULTS: The study cohort comprised 77,965 workers who accrued nearly 1.9 million person-years of follow up (mean 24.2 years). Mortality follow up, estimated as 99% complete, showed that 20,236 workers had died by 31 December 1996, with cause of death obtained for 98%. Workers experienced low overall mortality (all causes of death SMR 0.83) and low cancer mortality (SMR 0.90). No significant increases in risk were found for any of the 40 specific cause of death categories, whereas for several causes the numbers of deaths were significantly below expectation. Analyses by occupational group and specific job titles showed no remarkable mortality patterns. Factory workers estimated to have been routinely exposed to chromate were not at increased risk of total cancer (SMR 0.93) or of lung cancer (SMR 1.02). Workers routinely exposed to TCE, PCE, or a mixture of solvents also were not at increased risk of total cancer (SMRs 0.86, 1.07, and 0.89, respectively), and the numbers of deaths for specific cancer sites were close to expected values. Slight to moderately increased rates of non-Hodgkin's lymphoma were found among workers exposed to TCE or PCE, but none was significant. A significant increase in testicular cancer was found among those with exposure to mixed solvents, but the excess was based on only six deaths and could not be linked to any particular solvent or job activity. Internal cohort analyses showed no significant trends of increased risk for any cancer with increasing years of exposure to chromate or solvents. CONCLUSIONS: The results from this large scale cohort study of workers followed up for over 3 decades provide no clear evidence that occupational exposures at the aircraft manufacturing factory resulted in increases in the risk of death from cancer or other diseases. Our findings support previous studies of aircraft workers in which cancer risks were generally at or below expected levels.   PMID:10615290

Boice, J. D.; Marano, D. E.; Fryzek, J. P.; Sadler, C. J.; McLaughlin, J. K.

1999-01-01

463

Propeller aircraft interior noise model  

NASA Astrophysics Data System (ADS)

An analytical model was developed to predict the interior noise of propeller-driven aircraft. The fuselage model is that of a cylinder with a structurally-integral floor. The cabin sidewall is stiffened by stringers and ring frames, and the floor by longitudinal beams. The cabin interior is covered with a sidewall treatments consisting of layers of porous material and an impervious trim septum. Representation of the propeller pressure field is utilized as input data in the form of the propeller noise signature at a series of locations on a grid over the fuselage structure. Results obtained from the analytical model are compared with test data measured by NASA in a scale model cylindrical fuselage excited by a model propeller.

Pope, L. D.; Wilby, E. G.; Wilby, J. F.

1984-07-01

464

[Glaucoma and aircraft pilot fitness].  

PubMed

Two completely different questions arise when considering glaucoma and fitness to fly: Firstly, what is the risk for a passenger with glaucoma? Secondly, what is the flight safety risk connected with pilots suffering from glaucoma? National requirements and international standards pay little regard to this disease. This is astonishing, given that the perception of flight information in the peripheral visual field is of great importance in the cockpit. On one hand, diagnostic glaucoma examinations for pilots are mainly insufficient, and on the other, progressive visual field deficiencies may go undetected because of long intervals between examinations. Intraocular pressure may increase while flying in aircraft, e.g. in the case of negative g-load. Frequent flights at high altitudes without pressurized cabin air and with decreased oxygen supply, and therefore decreased tissue oxygen saturation, may represent a risk, especially for patients with progressive nerve fibre loss. PMID:8867166

Schwartz, R; Stern, C; Klemm, M; Draeger, J; Winter, R

1996-02-01

465

Multisensor/multimission surveillance aircraft  

NASA Astrophysics Data System (ADS)

The realignment of international powers, and the formation of new nations has resulted in increasing worldwide concern over border security, an expanding refugee problem, protection of fishery and mineral areas, and smuggling of all types. The focus on military services, to protect or defend against these threats of vital, national interest, is shifting to other government agencies and even commercial contractors to apply innovative and cost effective solutions. Previously, airborne surveillance and reconnaissance platforms have been large, mission dedicated military aircraft. The time has arrived for a smaller, more efficient, and more effective airborne capability. This paper briefly outlines a system of systems approach that smaller nations can afford to incorporate in their budgets, while greatly expanding their surveillance capability. The characteristics of specific cameras and sensors are purposely not addressed, so the emphasis can be placed on the integration of multiple sensors and capabilities.

Jobe, John T.

1994-10-01

466

Propeller aircraft interior noise model  

NASA Technical Reports Server (NTRS)

An analytical model was developed to predict the interior noise of propeller-driven aircraft. The fuselage model is that of a cylinder with a structurally-integral floor. The cabin sidewall is stiffened by stringers and ring frames, and the floor by longitudinal beams. The cabin interior is covered with a sidewall treatments consisting of layers of porous material and an impervious trim septum. Representation of the propeller pressure field is utilized as input data in the form of the propeller noise signature at a series of locations on a grid over the fuselage structure. Results obtained from the analytical model are compared with test data measured by NASA in a scale model cylindrical fuselage excited by a model propeller.

Pope, L. D.; Wilby, E. G.; Wilby, J. F.

1984-01-01

467

Aircraft wing structure detail design  

NASA Technical Reports Server (NTRS)

The provisions of this project call for the design of the structure of the wing and carry-through structure for the Viper primary trainer, which is to be certified as a utility category trainer under FAR part 23. The specific items to be designed in this statement of work were Front Spar, Rear Spar, Aileron Structure, Wing Skin, and Fuselage Carry-through Structure. In the design of these parts, provisions for the fuel system, electrical system, and control routing were required. Also, the total weight of the entire wing planform could not exceed 216 lbs. Since this aircraft is to be used as a primary trainer, and the SOW requires a useful life of 107 cycles, it was decided that all of the principle stresses in the structural members would be kept below 10 ksi. The only drawback to this approach is a weight penalty.

Sager, Garrett L.; Roberts, Ron; Mallon, Bob; Alameri, Mohamed; Steinbach, Bill

1993-01-01

468

Noise Reduction of Aircraft Flap  

NASA Technical Reports Server (NTRS)

A reduction in noise radiating from a side of a deployed aircraft flap is achieved by locating a slot adjacent the side of the flap, and then forcing air out through the slot with a suitable mechanism. One, two or even three or more slots are possible, where the slot is located at one;or more locations selected from a group of locations comprising a top surface of the flap, a bottom surface of the flap, an intersection of the top and side surface of the flap, an intersection of the bottom and side surfaces of the flap, and a side surface of the flap. In at least one embodiment the slot is substantially rectangular. A device for adjusting a rate of the air forced out through the slot can also be provided.

Hutcheson, Florence V. (Inventor); Brooks, Thomas F. (Inventor)

2009-01-01

469

41 CFR 102-33.225 - How must we manage aircraft parts?  

Code of Federal Regulations, 2012 CFR

...Aircraft and Aircraft Parts Managing Aircraft Parts § 102-33.225 How must we manage aircraft parts? You must manage your aircraft parts by maintaining proper storage, protection, maintenance procedures, and records for the...

2012-01-01

470

41 CFR 102-33.225 - How must we manage aircraft parts?  

Code of Federal Regulations, 2010 CFR

...Aircraft and Aircraft Parts Managing Aircraft Parts § 102-33.225 How must we manage aircraft parts? You must manage your aircraft parts by maintaining proper storage, protection, maintenance procedures, and records for the...

2010-07-01

471

41 CFR 102-33.225 - How must we manage aircraft parts?  

Code of Federal Regulations, 2013 CFR

...Aircraft and Aircraft Parts Managing Aircraft Parts § 102-33.225 How must we manage aircraft parts? You must manage your aircraft parts by maintaining proper storage, protection, maintenance procedures, and records for the...

2013-07-01

472

Turboprop aircraft against terrorism: a SWOT analysis of turboprop aircraft in CAS operations  

NASA Astrophysics Data System (ADS)

Today, the threat perception is changing. Not only for countries but also for defence organisations like NATO, new threat perception is pointing terrorism. Many countries' air forces become responsible of fighting against terorism or Counter-Insurgency (COIN) Operations. Different from conventional warfare, alternative weapon or weapon systems are required for such operatioins. In counter-terrorism operations modern fighter jets are used as well as helicopters, subsonic jets, Unmanned Aircraft Systems (UAS), turboprop aircraft, baloons and similar platforms. Succes and efficiency of the use of these platforms can be determined by evaluating the conditions, the threats and the area together. Obviously, each platform has advantages and disadvantages for different cases. In this research, examples of turboprop aircraft usage against terrorism and with a more general approach, turboprop aircraft for Close Air Support (CAS) missions from all around the world are reviewed. In this effort, a closer look is taken at the countries using turboprop aircraft in CAS missions while observing the fields these aircraft are used in, type of operations, specifications of the aircraft, cost and the maintenance factors. Thus, an idea about the convenience of using these aircraft in such operations can be obtained. A SWOT analysis of turboprop aircraft in CAS operations is performed. This study shows that turboprop aircraft are suitable to be used in counter-terrorism and COIN operations in low threat environment and is cost benefical compared to jets.

Yavuz, Murat; Akkas, Ali; Aslan, Yavuz

2012-06-01

473

Residents' annoyance responses to aircraft noise events  

NASA Technical Reports Server (NTRS)

In a study conducted in the vicinity of Salt Lake City International Airport, community residents reported their annoyance with individual aircraft flyovers during rating sessions conducted in their homes. Annoyance ratings were obtained at different times of the day. Aircraft noise levels were measured, and other characteristics of the aircraft were noted by trained observers. Metrics commonly used for assessing aircraft noise were compared, but none performed significantly better than A-weighted sound pressure level. A significant difference was found between the ratings of commercial jet aircraft and general aviation propeller aircraft, with the latter being judged less annoying. After the effects of noise level were accounted for, no significant differences were found between the ratings of landings and takeoffs. Aircraft noise annoyance reactions are stronger in lowered ambient noise conditions. This is consistent with the theory that reduced nighttime and evening ambient levels could create different reactions at different times of day. After controlling for ambient noise in a multiple regression analysis, no significant differences were found between the ratings of single events obtained during the three time periods: morning, afternoon, and evenings.

Dempsey, T. K.; Stephens, D. G.; Fields, J. M.; Shepherd, K. P.

1983-01-01

474

Combat aircraft noise: The operator's perspective  

NASA Astrophysics Data System (ADS)

Combat aircraft are not subject to the same noise reduction regulations as civil aircraft. Additionally, combat aircraft are operated closer to their performance limits and at high power settings for extended periods. There is general pressure to reduce noise of all kinds, but particularly noise from low flying aircraft. Although there is little that can be done to quiet in-service engines, operational palliatives, such as noise abatement procedures and restrictions on low flying, have been introduced. Moreover, there has been a concerted education and public relations campaign, and numerous airspace management changes have been introduced to reduce the impact of low flying on the population. These subjects were considered during a Pilot Study into aircraft noise under the auspices of the NATO Committee on the Challenges of Modern Society; the findings of the Study are discussed, giving both the international viewpoint and the UK perspective in particular. Some options for the reduction of low flying are also considered, but so long as military aircraft need to fly low to evade enemy air defences, low flying will remain a principal tactic of NATO air forces, and peacetime training will remain an essential military requirement. Thus, noise from low flying combat aircraft will remain a sensitive issue, and ways of reducing it will continue to be of importance for many years to come.

Bogg, R.

1992-04-01

475

A NOTE ON LIGHTNING STRIKES TO AIRCRAFT  

E-print Network

A DC-6 research aircraft was struck by lightning on three occasions during a thunderstorm research project at Flagstaff, Aria., in July 1967. Electric fields and meteorological parameters were measured and recorded. Similar conditions existed at the time of the lightning strikes. Each event occurred in a dissipating cumulonimbus, near the freezing level and in a region containing both ice and water. Corona discharge from the aircraft occurred prior to each strike. The possibility exists that one or more of the lightning strikes were triggered by the aircraft.

November William E. Cobb; F. James Holitza; William E. Cobb; F. James Holitza

476

Role of research aircraft in technology development  

NASA Technical Reports Server (NTRS)

The United States's aeronautical research program has been rich in the use of research aircraft to explore new flight regimes, develop individual aeronautical concepts, and investigate new vehicle classes and configurations. This paper reviews the NASA supercritical wing, digital fly-by-wire, HiMAT, and AD-1 oblique-wing flight research programs, and draws from these examples general conclusions regarding the role and impact of research aircraft in technology development. The impact of a flight program on spinoff technology is also addressed. The secondary, serendipitous results are often highly significant. Finally, future research aircraft programs are examined for technology trends and expected results.

Szalai, K. J.

1984-01-01

477

The dispersion of propellants from aircraft  

NASA Technical Reports Server (NTRS)

Two aspects of the dispersion of pollutants from aircraft are reviewed. The first is the dispersal of aircraft exhaust emissions in the vicinity of airports; the second is the dispersal of exhaust trails in the upper atmosphere. Techniques available for modeling this dispersal and how they might be applied to the airport problem are discussed. Field studies of airport pollution are then reviewed to assess current pollutant levels around airports and the aircraft's contribution to those levels. The possibility of contrail formation from jet emissions at high altitude is then considered and the effect of uncertainties in the trial mixing processes evaluated.

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

1974-01-01

478

Aircraft Loss-of-Control Accident Analysis  

NASA Technical Reports Server (NTRS)

Loss of control remains one of the largest contributors to fatal aircraft accidents worldwide. Aircraft loss-of-control accidents are complex in that they can result from numerous causal and contributing factors acting alone or (more often) in combination. Hence, there is no single intervention strategy to prevent these accidents. To gain a better understanding into aircraft loss-of-control events and possible intervention strategies, this paper presents a detailed analysis of loss-of-control accident data (predominantly from Part 121), including worst case combinations of causal and contributing factors and their sequencing. Future potential risks are also considered.

Belcastro, Christine M.; Foster, John V.

2010-01-01

479

En route noise of two turboprop aircraft  

NASA Technical Reports Server (NTRS)

In order to weigh en route noise emissions originating from future propfan powered aircraft, a data base of emission levels from conventional turboprop aircraft is needed. For this reason flyover noise measurements on two twin-engine turboprop aircraft were conducted at flight heights between 17,000 and 21,000 ft. Acoustic data are presented together with propeller operational parameters and environmental meteorological data. Narrowband spectral analyses demonstrate the characteristic features of the measured propeller noise signatures: Noise spectra are dominated by the propeller rotational noise fundamental frequency and pronounced noise beats occur as a consequence of different rotational speeds of the propellers.

Dobrzynski, Werner

1990-01-01

480

Aircraft Sensor Platform Has Increased Angular Range  

NASA Technical Reports Server (NTRS)

Mechanism rotates and translates instrument platform within pressure housing in aircraft to aim remote-sensing instrument toward target on ground below. Enables instrument to look under aircraft structure at larger fore and aft angles without having to deploy instrument into air stream outside. Also provides 10 degrees of yaw compensation, reducing further need for adjustment of attitude of aircraft to keep target in sight. With yaw compensation, pilot can fly with wings level and nose pointed into crosswind while on desired flight path over target.

Dabney, Philip W.; Bhardwaj, Suneel

1995-01-01

481

Aircraft battle damage repair - A force multiplier  

SciTech Connect

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 minimum effective requirements for BDR support, and the method can facilitate the return of 50 percent of damaged aircraft within 24 hours.

Hess, J.W. (USAF, Wright Laboratory, Wright-Patterson AFB, OH (United States))

1992-08-01

482

Multidisciplinary Techniques and Novel Aircraft Control Systems  

NASA Technical Reports Server (NTRS)

The Aircraft Morphing Program at NASA Langley Research Center explores opportunities to improve airframe designs with smart technologies. Two elements of this basic research program are multidisciplinary design optimization (MDO) and advanced flow control. This paper describes examples where MDO techniques such as sensitivity analysis, automatic differentiation, and genetic algorithms contribute to the design of novel control systems. In the test case, the design and use of distributed shape-change devices to provide low-rate maneuvering capability for a tailless aircraft is considered. The ability of MDO to add value to control system development is illustrated using results from several years of research funded by the Aircraft Morphing Program.

Padula, Sharon L.; Rogers, James L.; Raney, David L.

2000-01-01

483

Crack detection on HU-25 Guardian aircraft  

SciTech Connect

An ultrasonic inspection method was developed at FAA`s Airworthiness Assurance NDI Validation Center (AANC) to easily and rapidly detect hidden fatigue cracks in the copilot vertical windshield post on USCG (Coast Guard) HU-25 `Guardian` aircraft. The inspection procedure locates hidden cracks as small as 3.2 mm emanating from internal fastener holes and determines their length. A test procedure was developed and a baseline assessment of the USCG fleet conducted. Inspection results on 41 aircraft revealed good correlation with results made during subsequent structural disassembly and visual inspection of selected aircraft.

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

1996-10-01

484

Aircraft radial-belted tire evaluation  

NASA Technical Reports Server (NTRS)

An overview is given of the ongoing joint NASA/FAA/Industry Surface Traction And Radial Tire (START) Program being conducted at NASA Langley's Aircraft Landing Dynamics Facility (ALDF). The START Program involves tests using three different tire sizes to evaluate tire rolling resistance, braking, and cornering performance throughout the aircraft ground operational speed range for both dry and wet runway surfaces. Preliminary results from recent 40 x 14 size bias-ply, radial-belted, and H-type aircraft tire tests are discussed. The paper concludes with a summary of the current program status and planned ALDF test schedule.

Yager, Thomas J.; Stubbs, Sandy M.; Davis, Pamela A.

1990-01-01

485

Maneuvering technology for advanced fighter aircraft  

NASA Technical Reports Server (NTRS)

The need for increased maneuverability has its genesis from the first aerial combat engagement when two adversaries entangled themselves in a deadly aerial dance trying to gain the advantage over the other. It has only been in the past two decades that technologies have been investigated to increase aircraft control at maneuver attitudes that are typically dominated by highly separated flows. These separated flow regions are aggravated by advanced fighter aircraft shapes required to defeat an electronic enemy. This paper discusses passive and active devices that can be used to enhance the maneuverability of advanced fighter aircraft through vortex flow control, boundary layer control, and innovative flow manipulation.

Alexander, Michael G.; Harris, Scott H.; Byers, Richard H.

1992-01-01

486

Environmental protection agency aircraft emissions standards  

NASA Technical Reports Server (NTRS)

Emissions of air pollutants from aircraft were investigated in order to determine: (1) the extent to which such emissions affect air quality in air quality control regions throughout the United States; and (2) the technological feasibility of controlling such emissions. The basic information supporting the need for aircraft emissions standards is summarized. The EPA ambient air quality standards are presented. Only the primary (health related) standards are shown. Of the six pollutants, only the first three, carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides, are influenced significantly by aircraft.

Kittredge, G. D.

1977-01-01

487

Research related to variable sweep aircraft development  

NASA Technical Reports Server (NTRS)

Development in high speed, variable sweep aircraft research is reviewed. The 1946 Langley wind tunnel studies related to variable oblique and variable sweep wings and results from the X-5 and the XF1OF variable sweep aircraft are discussed. A joint program with the British, evaluation of the British "Swallow", development of the outboard pivot wing/aft tail configuration concept by Langley, and the applied research program that followed and which provided the technology for the current, variable sweep military aircraft is outlined. The relative state of variable sweep as a design option is also covered.

Polhamus, E. C.; Toll, T. A.

1981-01-01

488

Outlook for advanced concepts in transport aircraft  

NASA Technical Reports Server (NTRS)

The present air transport system is expected to continue until the turn of the century, but significant technological advances will have been incorporated into the existing aircraft. With a few exceptions, such as the SST, the development of all-new transports will be inhibited by economic constraints. The outlook for advanced transport aircraft concepts in the 21st century indicates new vehicles may be developed, such as air cushion landing gears, away from the airport; flatbed transports, at the airport; and aerial relay transports, in the air. Some of the new technologies and vehicle configurations are discussed, and their impact on aircraft maintenance, airport runways, taxiways, and cargo loading facilities is examined.

Conner, D. W.

1980-01-01

489

Improvements in teaching aircraft engine design  

SciTech Connect

Aircraft gas turbine analysis and design pedagogy can be enriched through the incorporation improved preliminary engine thrust and fuel consumption models, novel computer programs for both aircraft system analysis and turbomechanical design, and a new perspective for engine-cycle analysis. Four computer programs have been developed for preliminary engine design; two of these automate aircraft system analysis, while another designs multistage axial-flow compressors and the last designs multistage axial-flow turbines. Student confusion with 'design-point' and 'off-design' concepts is by these means reduced. 6 refs.

Mattingly, J.D.; Heiser, W.H. (Seattle, University, WA (United States) Tennessee, University, Tullahoma (United States))

1992-07-01

490

Aircraft Energy Efficiency (ACEE) status report  

NASA Technical Reports Server (NTRS)

Fuel efficiency in aeronautics, for fuel conservation in general as well as for its effect on commercial aircraft operating economics is considered. Projects of the Aircraft Energy Efficiency Program related to propulsion are emphasized. These include: (1) engine component improvement, directed at performance improvement and engine diagnostics for prolonged service life; (2) energy efficient engine, directed at proving the technology base for the next generation of turbofan engines; and (3) advanced turboprop, directed at advancing the technology of turboprop powered aircraft to a point suitable for commercial airline service. Progress in these technology areas is reported.

Nored, D. L.; Dugan, J. F., Jr.; Saunders, N. T.; Ziemianski, J. A.

1979-01-01

491

Daedalus Project's Light Eagle - Human powered aircraft  

NASA Technical Reports Server (NTRS)

The Michelob Light Eagle is seen here in flight over Rogers Dry Lake at the NASA Dryden Flight Research Center, Edwards, California. The Light Eagle and Daedalus human powered aircraft were testbeds for flight research conducted at Dryden between January 1987 and March 1988. These unique aircraft were designed and constructed by a group of students, professors, and alumni of the Massachusetts Institute of Technology within the context of the Daedalus project. The construction of the Light Eagle and Daedalus aircraft was funded primarily by the Anheuser Busch and United Technologies Corporations, respectively, with additional support from the Smithsonian Air and Space Museum, MIT, and a number of other sponsors. To celebrate the Greek myth of Daedalus, the man who constructed wings of wax and feathers to escape King Minos, the Daedalus project began with the goal of designing, building and testing a human-powered aircraft that could fly the mythical distance, 115 km. To achieve this goal, three aircraft were constructed. The Light Eagle was the prototype aircraft, weighing 92 pounds. On January 22, 1987, it set a closed course distance record of 59 km, which still stands. Also in January of 1987, the Light Eagle was powered by Lois McCallin to set the straight distance, the distance around a closed circuit, and the duration world records for the female division in human powered vehicles. Following this success, two more aircraft were built, the Daedalus 87 and Daedalus 88. Each aircraft weighed approximately 69 pounds. The Daedalus 88 aircraft was the ship that flew the 199 km from the Iraklion Air Force Base on Crete in the Mediterranean Sea, to the island of Santorini in 3 hours, 54 minutes. In the process, the aircraft set new records in distance and endurance for a human powered aircraft. The specific areas of flight research conducted at Dryden included characterizing the rigid body and flexible dynamics of the Light Eagle, investigating sensors for an autopilot that could be used on high altitude or human powered aircraft, and determining the power required to fly the Daedalus aircraft. The research flights began in late December 1987 with a shake-down of the Light Eagle instrumentation and data transfer links. The first flight of the Daedalus 87 also occurred during this time. On February 7, 1988, the Daedalus 87 aircraft crashed on Rogers Dry Lakebed. The Daedalus 88, which later set the world record, was then shipped from MIT to replace the 87's research flights, and for general checkout procedures. Due to the accident, flight testing was extended four weeks and thus ended in mid-March 1988 after having achieved the major goals of the program; exploring the dynamics of low Reynolds number aircraft, and investigating the aeroelastic behavior of lightweight aircraft. The information obtained from this program had direct applications to the later design of many high-altitude, long endurance aircraft.

1987-01-01

492

Trajectory generation for aircraft subject to dynamic weather uncertainty  

Microsoft Academic Search

Determining safe aircraft trajectories that avoid hazardous weather regions and other aircraft while efficiently using the available airspace is an important problem. Although tactical weather forecast maps have been available, their use in automated aircraft trajectory generation has not been fully explored or implemented. We consider aircraft trajectory generation using forecast data available from the Corridor Integrated Weather System product.

Maryam Kamgarpour; Vera Dadok; Claire Tomlin

2010-01-01

493

Multiple Aircraft Deconflicted Path Planning with Weather Avoidance Constraints  

E-print Network

Aircraft velocity, (units: meters/second) h Aircraft altitude, (units: meters) P Atmospheric pressure centralized at the sector level are applied by Air Traffic Controllers to aircraft for conflict resolution.1 aircraft at a time, due to flow management techniques applied at the Air Route Traffic Control Center

Sastry, S. Shankar

494

L-Band Commercial Communications Service for Unmanned Aircraft Systems  

Microsoft Academic Search

Significant effort is being expended defining the requirements for unmanned aircraft to fly in the National Airspace System (NAS). The goal is for an unmanned aircraft to be able to file a flight plan and fly in the NAS with no more restrictions than those imposed on a manned aircraft. The result would be unmanned and manned aircraft flying together

T. P. Mulkerin

2007-01-01

495

Mathematical Models for Aircraft Trajectory Design : A Survey  

E-print Network

Mathematical Models for Aircraft Trajectory Design : A Survey D. Delahaye and S. Puechmorel and P to aircraft trajectory design. Fi- nally, we introduce some path planning techniques via natural language and maintaining separation between aircraft. After giving some definitions, some typical feature of aircraft

Paris-Sud XI, Université de

496

DESIGN OFA SUPERVISED FLIGHT CONTROLSYSTEM FOR AIRCRAFT RELATIVE GUIDANCE  

E-print Network

DESIGN 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.Thus, the expectedbenefit of suchnew capabilities onboard aircraft is an increase of air traffic controller availability

Paris-Sud XI, Université de

497

Unmanned Aircraft Collision Avoidance using Continuous-State POMDPs  

E-print Network

Unmanned Aircraft Collision Avoidance using Continuous-State POMDPs Haoyu Bai David Hsu Mykel J. INTRODUCTION Unmanned aircraft have great potential for military, scien- tific, and commercial applications is that unmanned aircraft do not yet have the capabil- ity to sense and avoid other aircraft effectively

Lee, Wee Sun

498

Presentation to the European Union against Aircraft Nuisances  

Microsoft Academic Search

The jet engine noise reduction achieved by the aircraft industry is discussed. A 100 fold change in acoustic energy is claimed for the high bypass ratio turbofan. The areas of contour of constant noise level at airports are given for a range of typical in-service and emerging aircraft. The replacement of existing aircraft by aircraft powered with modern technology engines

M. J. T. Smith

1980-01-01

499

Aircraft Engine Performance Study Using Flight Data Recorder Archives  

E-print Network

Aircraft Engine Performance Study Using Flight Data Recorder Archives Yashovardhan S. Chati emissions are a significant source of pollution and are closely related to engine fuel burn. The onboard for different aircraft and engine types, given the trajectory of an aircraft. I. Introduction Aircraft emissions

Gummadi, Ramakrishna

500

Fire-resistant aircraft materials development and evaluation program  

NASA Technical Reports Server (NTRS)

An aircraft flammability program was undertaken to utilize spacecraft developed fire-resistant materials to improve passenger safety and decrease losses from unattended fires in commercial aircraft. Five full-scale aircraft flammability tests were performed to evaluate the effectiveness of improved fire-resistant materials by comparing their burning characteristics with those of pre-1968 aircraft materials.

Bricker, R. W.; Stuckey, R. N.

1975-01-01