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Effect of Compressibility at High Subsonic Velocities on the Lifting Force Acting on an Elliptic Cylinder
An extended form of the Ackeret iteration method, applicable to arbitrary profiles, is utilized to calculate the compressible flow at high subsonic velocities past an elliptic cylinder. The angle of attack to the direction of the undisturbed stream is small and the circulation is fixed by the Kutta condition at the trailing end of the major axis. The expression for the lifting force on the elliptic cylinder is derived and shows a first-step improvement of the Prandtl-Glauert rule. It is further shown that the expression for the lifting force, although derived specifically for an elliptic cylinder, may be extended to arbitrary symmetrical profiles.
Effect of Engine Skew on Directional and Lateral Control Characteristics of Single-Engine Airplanes
Report discussing an investigation on the effect of engine skew on the directional and lateral control characteristics of a single-engine airplane with a single-rotating propeller. The estimated and test results showed an advantage to skewing the propeller, as it assists with overcoming inadequate rudder control in power-on flight and aileron control, especially with flaps deflected.
Effect of hot-gas bleedback ice prevention on performance of a turbojet engine with fixed-area tail-pipe nozzle
Report presenting the results of an analytical investigation, which demonstrated that the inlet of a turbojet engine can be protected from ice accretions by bleeding hot gases from other locations within the engine to the inlet without undue loss in thrust. Results regarding the bleedback requirements, engine performance, effect of nozzle area, mixing efficiency, and seriousness of thrust losses are provided.
A Method for Determining the Camber and Twist of a Surface to Support a Given Distribution of Lift, With Applications to the Load Over a Sweptback Wing
"A graphical method is described for finding the shape (camber and twist) of an airfoil having an arbitrary distribution of lift. The method consists in replacing the lifting surface and its wake with an equivalent arrangement of vortices and in finding the associated vertical velocities. By division of the vortex pattern into circular strips concentric about the downwash point instead of into the usual rectangular strips, the lifting surface is reduced for each downwash point to an equivalent loaded line for which the induced velocity is readily computed" (p. 543).
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