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Effect of engine position and high lift devices on aerodynamic characteristics of external flow, jet flap STOL model - graphs
Wind tunnel tests to determine low-speed aerodynamic characteristics of large-scale STOL transport model with augmented jet flap
Static tests of augmentor-wing flap system for modified C-8A jet STOL research airplane using 0.7 scale model
Noise data with models of both internally and externally blown jet flaps designed for STOL aircraft
Wind tunnel measurements of pressure distributions on wing having NACA 4415 airfoil sections with trailing-edge flaps set at 0 deg and 40 deg
Full scale wind tunnel tests of low wing, single engine, light aircraft with positive and negative propeller thrust and up and down flap deflection - graphs
Investigating bidirectional jet flap device for application to helicopter rotors
Wind tunnel tests of swept wing jet transport aircraft model with four pod mounted engines under wing and external flow, jet augmented double slotted flap
Dynamic stability of jet transport configuration with high thrust-weight ratio and externally blown jet flap
Wind tunnel static longitudinal stability and control characteristics of cruciform delta winged missile with various horizontal canards and trailing-edge flap control between Mach 1.50 and 4.63
Aerodynamic characteristics of twin jet, swept wing fighter aircraft model with leading edge Kreuger flaps at subsonic speeds
Comparative vertical turbulence and loss restrictive stochastic models for threshold crossing rotor blade flapping vibrations at low lift high advance ratio
A jet-flap blade was designed for a velocity diagram typical of the first-stage stator of a jet engine turbine and was tested in a simple two-dimensional cascade of six blades. The principal measurements were blade surface static pressure and cross-channel surveys of exit total pressure, static pressure, and flow angle. The results of the experimental investigation include blade loading, exit angle, flow, and loss data for a range of exit critical velocity ratios and three jet flow conditions.
Data of tests of a large-scale swept augmentor wing model in the 40- by 80-foot wind tunnel are presented. The data includes longitudinal characteristics with and without a horizontal tail as well as results of preliminary investigation of lateral-directional characteristics. The augmentor flap deflection was varied from 0 deg to 70.6 deg at isentropic jet thrust coefficients of 0 to 1.47. The tests were made at a Reynolds number from 2.43 to 4.1 times one million.
A fixed-base simulator study was conducted to determine the flight characteristics of a representative STOL transport having a high wing and equipped with an external-flow jet flap in combination with four high-bypass-ratio fan-jet engines during the approach and landing. Real-time digital simulation techniques were used. The computer was programed with equations of motion for six degrees of freedom and the aerodynamic inputs were based on measured wind-tunnel data. A visual display of a STOL airport was provided for simulation of the flare and touchdown characteristics. The primary piloting task was an instrument approach to a breakout at a 200-ft ceiling with a visual landing.
Noise tests were conducted using simulated mixer-type nozzles and a small scale model of an externally blown flap, lift augmentation system. The mixer nozzles were simulated with orifice plates.
The stability of the flapping motion of a single blade of a helicopter rotor is examined using the techniques of perturbation theory. The equation of motion studied is linear, with periodic aerodynamic coefficients due to the forward speed of the rotor. Solutions are found for four cases: small and large advance ratio and small and large Lock number. The perturbation techniques appropriate to each case are discussed and illustrated in the course of the analysis. The application of perturbation techniques to other problems in rotor dynamics is discussed. It is concluded that perturbation theory is a powerful mathematical technique which should prove very useful in analyzing some of the problems of helicopter dynamics.
Screening tests of upper surface blowing on externally blown flaps configurations were conducted. Noise and turning effectiveness data were obtained with small-scale, engine-over-the-wing models. One large model was tested to determine scale effects. Nozzle types included circular, slot, D-shaped, and multilobed. Tests were made with and without flow attachment devices. For STOL applications the particular multilobed mixer and the D-shaped nozzles tested were found to offer little or no noise advantage over the round convergent nozzle. High aspect ratio slot nozzles provided the quietest configurations. In general, upper surface blowing was quieter than lower surface blowing for equivalent EBF models.