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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Advanced spacecraft recovery flight tests using radio controlled model airplane techniques involving gliding parachute models launched from carrier models
Terminal area VTOL aircraft operation, discussing flight research, instrument approach, glide path, speed control, handling characteristics, etc
Lifting body entry vehicles in low speed flight test program for determining handling qualities, discussing M2-F2 glide flights
Hypervelocity glide vehicle optimum maneuvers, finding lift optimal control law for maximization of final velocity or altitude
Ground based guidance for land-landing manned spacecraft with low velocity descent systems, discussing high and low altitude glide path intercept and spiral
Subsonic glide landing approach guidance for unpowered lifting vehicles, using perturbation feedback and approximation of heading and position coordinates
Wind tunnel, gliding, and deployment tests of all-flexible, single keel and double keel parawing models
Delta winged, manned reentry vehicle capable of horizontal glide landing at low speeds
Subsonic glide landing approach guidance for unpowered lifting vehicles, using perturbation feedback and approximation of heading and position coordinates
Nonrolling lifting gliding vehicle hypersonic longitudinal dynamic stability, applying analysis to space shuttles
Terminal entry trajectory analysis for spiral glide descent of space shuttle to landing site
Light aircraft spoilers to minimize landing risk, discussing spoiler/dive brake area effects on glide path angular control
Compressive creep of aluminum oxide single crystals deformed by dislocation glide and rhombohedral twinning, investigating activation energy and rate controlling mechanism
A computerized analysis procedure, based on a control theoretic model of the human pilot, is used to evaluate display requirements for longitudinal control in the landing approach. The display employed a digitally generated, perspective runway image with a superimposed artificial horizon for pitch indication. System performance measures are obtained for the approach phase of a light aircraft and a DC-8; predictions are made as to the effects of several display modifications. It is found that augmenting the basic display with glide slope reference bars and a velocity aim point yields adequate performance in calm air. Under moderate turbulence, the augmented display appears to be adequate for a DC-8 approach but not for a light aircraft.
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.
An in-flight investigation was made to determine the terminal-area operating problems of a vectored-thrust-jet vertical and short take-off landing (V/STOL) airplane under simulated instrument conditions. Handling-qualities data pertinent to the terminal-area approach and landing task are presented in the text, and additional documentation is included in the appendixes. Problems dealing with the cruise letdown to localizer capture, conversion to powered-lift flight, precise control of the glide slope, approach velocity or deceleration schedule, hover, and landing are discussed.
Measurements and interpretations of single and mutiloop pilot response properties during simulated instrument approach are presented. Pilot subjects flew Category 2-like ILS approaches in a fixed base DC-8 simulaton. A conventional instrument panel and controls were used, with simulated vertical gust and glide slope beam bend forcing functions. Reduced and interpreted pilot describing functions and remmant are given for pitch attitude, flight director, and multiloop (longitudinal) control tasks. The response data are correlated with simultaneously recorded eye scanning statistics, previously reported in NASA CR-1535. The resulting combined response and scanning data and their interpretations provide a basis for validating and extending the theory of manual control displays.
The design and operational characteristics of the X-24A are described in detail. Primary emphasis is placed on the safety considerations incorporated in the design and flight test stages. It is pointed out that the inherently high drag of the lifting body configuration together with its relatively low lift/drag ratio, generated considerable concern with respect to the pilot's ability to perform safe landings from gliding flight. The resulting safety procedures taken at each stage of development are discussed.