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An engineering approach was used to include the nonlinear effects of thickness and camber in an analytical aeroelastic analysis of cascades in supersonic acial flow (supersonic leading-edge locus). A hybrid code using Lighthill's nonlinear piston theory and Lanes's linear potential theory was developed to include these nonlinear effects. Lighthill's theory was used to calculate the unsteady pressures on the noninterference surface regions of the airfoils in cascade. Lane's theory was used to calculate the unsteady pressures on the remaining interference surface regions. Two airfoil profiles was investigated (a supersonic throughflow fan design and a NACA 66-206 airfoil with a sharp leading edge). Results show that compared with predictions of Lane's potential theory for flat plates, the inclusion of thickness (with or without camber) may increase or decrease the aeroelastic stability, depending on the airfoil geometry and operating conditions. When thickness effects are included in the aeroelastic analysis, inclusion of camber will influence the predicted stability in proportion to the magnitude of the added camber. The critical interblade phase angle, depending on the airfoil profile and operating conditions, may also be influenced by thickness and camber. Compared with predictions of Lane's linear potential theory, the inclusion of thickness and camber decreased the aerodynamic stifness and increased the aerodynamic damping at Mach 2 and 2.95 for a cascade of supersonic throughflow fan airfoils oscillating 180 degrees out of phase at a reduced frequency of 0.1.

An engineering approach was used to include the nonlinear effects of thickness and camber in an analytical aeroelastic analysis of cascades in supersonic acial flow (supersonic leading-edge locus). A hybrid code using Lighthill's nonlinear piston theory and Lanes's linear potential theory was developed to include these nonlinear effects. Lighthill's theory was used to calculate the unsteady pressures on the noninterference surface regions of the airfoils in cascade. Lane's theory was used to calculate the unsteady pressures on the remaining interference surface regions. Two airfoil profiles was investigated (a supersonic throughflow fan design and a NACA 66-206 airfoil with a sharp leading edge). Results show that compared with predictions of Lane's potential theory for flat plates, the inclusion of thickness (with or without camber) may increase or decrease the aeroelastic stability, depending on the airfoil geometry and operating conditions. When thickness effects are included in the aeroelastic analysis, inclusion of camber will influence the predicted stability in proportion to the magnitude of the added camber. The critical interblade phase angle, depending on the airfoil profile and operating conditions, may also be influenced by thickness and camber. Compared with predictions of Lane's linear potential theory, the inclusion of thickness and camber decreased the aerodynamic stifness and increased the aerodynamic damping at Mach 2 and 2.95 for a cascade of supersonic throughflow fan airfoils oscillating 180 degrees out of phase at a reduced frequency of 0.1.

Presented in this document are the test results of Nuclear Radiation Effects Tests No. 18 which was a dynamic credibility demonstration conducted in the Air Force Ground Test Reactor during the time period of 29 July through 5 August 1964. This work was performed in support of Air Force Contract AF33(657)- 12517. Planning and execution of the irradiation provided specific test data on subsystems, components, and materials representative of those which would be used in a nuclear powered ramjet missile. The test articles evaluated were the product of an extensive development program to provide nuclear radiation tolerant subsystems which would meet the LASV-N performance characteristics. The test articles representing the major subsystem areas(digital computer simulator, A to D shaft position encoder, magnetic core controlled multiplexer, two axis inertial platform subsystem, rate gyros and accelerometers, and electromechanical filter system) were dynamically irradiated during a total exposure of 187 Mw-hrs.

The purpose of this study was to evaluate the capacity of the Naval Air Turbine Test Station's altitude test facility in terms of supersonic aerodynamic research and free jet air breathing engine testing. The evaluation was made to determine: (1) the extent of supersonic operation available; (2) the effect of various tunnel diffuser configurations; (3) the magnitude of the Reynolds number per inch parameter; (4) the approximate air breathing engine size that may be accommodated; and (5) a configuration and the values for certain parameters in a design point tunnel.

The method, which utilized hybrid tandem solutions involving Generalized Newtonian and Shock-Expansion theories, provides accurate results for a variety of nose shapes and fineness ratios over a range of supersonic/ hypersonic Mach numbers. The numerical simplicity of the method, which makes it readily applicable for quick hand-calculational procedures, was the prime factor in its selection and publication. The investigation for lifting bodies indicates the present method is applicable for bodies of revolution at angles of attack up to about ten degrees. The report presents numerical examples showing stepwise calculational procedures for obtaining pressure coefficient and local Mach number distributions along the meridians of a body of revolution at angle of attack.

The design characteristics, operational capabilities, and instrumentation systems of the supersonic compressor test facilities at AEDC are described and the results of shakedown tests are presented. These facilities consist of (1) a high-speed rotating machine to test 22-in.-diam, single-stage, axial-flow compressor rotors from 5,000 to 17,000 rpm at rotor tip speeds up to 1630 ft/sec and (2) a continuous-flow cascade rig with a 1- by 1.3-in. test section to test the effects of various blade parameters such as area ratio and angle of attack. The primary purpose of these facilities is for further development and evaluation of the concept of blunt-trailing edge, supersonic compressor blades. (Author)

The air transportation system is comprised of the following basic elements; Airlines; Airports; Governmental facilities and agencies; Passengers and cargo; and Airplane.