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Characteristics of six propellers including the high-speed range

Description: This investigation is part of an extensive experimental study that has been carried out at full scale in the NACA 20-foot tunnel, the purpose of which has been to furnish information in regard to the functioning of the propeller-cowling-nacelle unit under all conditions of take-off, climbing, and normal flight. This report presents the results of tests of six propellers in the normal and high-speed flight range and also includes a study of the take-off characteristics.
Date: June 4, 1936
Creator: Theodorsen, Theodore; Stickle, George W. & Brevoort, M. J.
Partner: UNT Libraries Government Documents Department
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Experimental Investigation of Wind-Tunnel Interference on the Downwash Behind an Airfoil

Description: "The interference of the wind-tunnel boundaries on the downwash behind an airfoil has been experimentally investigated and the results have been compared with the available theoretical results for open-throat wind tunnels. As in previous studies, the simplified theoretical treatment that assumes the test section to be an infinite free jet has been shown to be satisfactory at the lifting line. The experimental results, however, show that this assumption may lead to erroneous conclusions regardin… more
Date: June 4, 1937
Creator: Silverstein, Abe & Katzoff, S.
Partner: UNT Libraries Government Documents Department
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Theoretical study of air forces on an oscillating or steady thin wing in a supersonic main stream

Description: From Summary: "A theoretical study, based on the linearized equations of motion for small disturbance, is made of the air forces on wings of general plan forms moving forward at a constant supersonic speed. The boundary problem is set up for both the harmonically oscillating and the steady conditions. Two types of boundary conditions are distinguished, which are designated "purely supersonic" and "mixed supersonic." the method is illustrated by applications to a number of examples for both the … more
Date: June 4, 1947
Creator: Garrick, I. E. & Rubinow, S. I.
Partner: UNT Libraries Government Documents Department
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Studies of the speed stability of a tandem helicopter in forward flight

Description: Flight-test measurements, related analytical studies, and corresponding pilots' opinions of the speed stability of tandem-rotor helicopter are presented. An undesirable instability, evidenced by rearward stick motion with increasing forward speed at constant power, is indicated to be caused by variations with speed of the front-rotor downwash at the rear rotor. An analytical expression for predicting changes in speed stability caused by changes in rotor geometry is derived and constants for use… more
Date: June 4, 1953
Creator: Tapscott, Robert J. & Amer, Kenneth B.
Partner: UNT Libraries Government Documents Department
open access

An experimental investigation of sting-support effects on drag and a comparison with jet effects at transonic speeds

Description: Various dummy stings were tested on the rear of a related series of afterbody shapes for Mach numbers from 0.80 to 1.10 and Reynolds numbers based on body length from 15.0 x 16 to the 6th power to 17.4 x 10 to the 6th power. A method is presented whereby approximate sting interference corrections can be made to models having afterbody shapes and sting supports similar to those of these tests if the Reynolds numbers are of the same order of magnitude and a turbulent boundary layer exists at the … more
Date: June 4, 1956
Creator: Cahn, Maurice S.
Partner: UNT Libraries Government Documents Department
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