SEARCH · Search NASA
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.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Transonic wind tunnel study of control span and large wing-tip nacelles results on effectiveness of spoiler-slot-deflector controls on fighter aircraft
Wind tunnel evaluation of speed brake effects on supersonic characteristics of variable sweep fighter aircraft models
Lifting entry vehicles night landing flight simulation by night approaches and landings of piloted fighter aircraft with low L/D ratio
Jet fighter aircraft lateral directional stability at high angles of attack
Factors affecting flat spin characteristics of fighter aircraft with horizontal tail surfaces
Effects of pointed nose on spin characteristics of fighter aircraft model and correlation of free flight test results with theoretical data
Transonic and supersonic dynamic stability characteristics of variable sweep wing tactical fighter aircraft
Feasibility of using fixed simulator to determine stall and spin characteristics of fighter aircraft
Static force tests of model of twin jet fighter aircraft at various angles of attack and sideslip angles to obtain data for theoretical spin studies
Aerodynamic characteristics of twin jet, swept wing fighter aircraft model with leading edge Kreuger flaps at subsonic speeds
Spin tunnel tests to determine effectiveness of deployable, flexible ventral fins for spin recovery device on fighter aircraft
The aerodynamic characteristics of a six-engine (four lift, two lift-cruise) lift-engine model obtained in the Ames 40- by 80-foot wind tunnel are presented. The model was an approximate one-half scale representation of a lift-engine VTOL fighter aircraft with a variable-sweep wing. The four lift-engines were housed in the aft fuselage with the inlets located above the wing. Longitudinal and lateral-directional force and moment data are presented for a range of exhaust gas momentum ratios (thrust coefficients). Wind tunnel forward speed was varied from 0 to 140 knots corresponding to a maximum Reynolds number of 6.7 million. The data are presented without analysis.
A recorder system has been installed on two operational fighter aircrafts. Signal values from a c.g.-acceleration transducer and a strain-gage installation at the wing root were sampled and recorded in digital format on the recorder system. To analyse such load-time histories for fatigue evaluation purposes, a number of counting methods are available in which level crossings, peaks, or ranges are counted. Ten different existing counting principles are defined. The load-time histories are analysed to evaluate these counting methods. For some of the described counting methods, the counting results might be affected by arbitrarily chosen parameters such as the magnitude of load ranges that will be neglected and other secondary counting restrictions. Such influences might invalidate the final counting results entirely. The evaluation shows that for the type of load-time histories associated with most counting methods, a sensible value of the parameters involved can be found.
Pyrotechnic systems, high burn rate propellant and explosive-actuated mechanisms, have been used extensively in aerospace vehicles to perform a variety of work functions, including crew escape, staging, deployment and destruction. Pyrotechnic system principles are described in this report along with their applications on typical military fighter aircraft, Mercury, Gemini, Apollo, and a representative unmanned spacecraft. To consider the possible pyrotechnic applications on the space shuttle the mechanical functions on a large commercial aircraft, similar in scale to the shuttle orbiter, were reviewed. Many potential applications exist for pyrotechnic system on the space shuttle, both in conventional short-duration functions and in longer duration and/or repetitive type gas generators.
This paper describes 'type 1' servo techniques applied to explicit model following systems. The advantages of using these are: (1) steady-state decoupling is provided for the controlled state variables as determined by a reference input (the pilot command for example), (2) overall stability of the decoupled adaptive scheme is guaranteed, (3) a zero steady-state error for those state variables incorporating integral feedback, to a constant input reference, and (4) improved transient performance. Example calculations have been performed using a mathematical model for a typical fighter aircraft and a desired performance reference model based on satisfactory aircraft flying qualities. Numerical results are given.
The development of a digital adaptive flight control algorithm is described that combines a weighted least squares estimator with optimal linear regulator control logic designed to minimize a quadratic model following performance index. Very promising results for a typical fighter aircraft's trajectory over six distinct flight conditions are reported.
Thrust-induced supercirculation effects from thrust vectoring have indicated a potential for not only increasing maneuverability of fighter aircraft but also as a means of improving cruise performance. The current study investigated a partial-span rectangular jet-exhaust nozzle located at the wing trailing edge that acts similar to a jet flap by increasing lift due to supercirculation. This paper summarizes experimental studies including the effects of nozzle deflection angle, wing camber, and nozzle shape and exit location on lift, drag and load distributions. The results indicate that significant increases in thrust-induced lift along with substantial decreases in drag are possible.
The contributions of a design deficiency, supervisory shortcoming, and pilot error to the occurrence of a major accident involving a mechanically intact fighter aircraft during VFR weather are analyzed. The need for physiologically oriented flight surgeons to exercise critical judgment about the adequacy of the man-machine interface is pointed out.