An investigation of the drag of windshields in the 8-foot high-speed wind tunnel (open access)

An investigation of the drag of windshields in the 8-foot high-speed wind tunnel

Report presents the results of tests made to determine the drag of closed-cockpit and transport-type windshields. The tests were made at speeds corresponding to a Mach number range of approximately 0.25 to 0.58 in the NACA 8-foot high-speed wind tunnel. This speed range corresponds to a test Reynolds number range of 2,510,000 to 4,830,000 based on the mean aerodynamic chord of the full-span model (17.29 in.). The shapes of the windshield proper, the hood, and the tail fairing were systematically varied to include common types and refined design.
Date: May 22, 1939
Creator: Robinson, Russell G. & Delano, James B.
System: The UNT Digital Library
Tensile Elastic Properties of 18:8 Chromium-Nickel Steel as Affected by Plastic Deformation (open access)

Tensile Elastic Properties of 18:8 Chromium-Nickel Steel as Affected by Plastic Deformation

"The relationship between stress and strain, and between stress and permanent set, for 18:8 alloy as affected by prior plastic deformation is discussed. Hysteresis and creep and their effects on the stress-strain and stress-set curves are also considered, as well as the influence of duration of the rest interval after cold work and the influence of plastic deformation on proof stresses, on the modulus of elasticity at zero stress, and on the curvature of the stress-strain line. A constant (c sub 1) is suggested to represent the variation of the modulus of elasticity with stress" (p. 539).
Date: November 22, 1938
Creator: McAdam, D. J., Jr. & Mebs, R. W.
System: The UNT Digital Library
Mechanism of flutter: A theoretical and experimental investigation of the flutter problem (open access)

Mechanism of flutter: A theoretical and experimental investigation of the flutter problem

From Summary: "The results of the basic flutter theory originally devised in 1934 and published as NACA Technical Report no. 496 are presented in a simpler and more complete form convenient for further studies. The paper attempts to facilitate the judgement of flutter problems by a systematic survey of the theoretical effects of the various parameters. A large number of experiments were conducted on cantilever wings, with and without ailerons, in the NACA high-speed wind tunnel for the purpose of verifying the theory and to study its adaptability to three-dimensional problems."
Date: September 22, 1938
Creator: Theodorsen, Theodore & Garrick, I. E.
System: The UNT Digital Library
Aircraft Accidents: Methods of Analysis (open access)

Aircraft Accidents: Methods of Analysis

This report is a revision of NACA-TR-357. It was prepared by the Committee on Aircraft Accidents. The purpose of this report is to provide a basis for the classification and comparison of aircraft accidents, both civil and military.
Date: June 22, 1936
Creator: Committee on Aircraft Accidents
System: The UNT Digital Library
The effect of turbulence on the drag of flat plates (open access)

The effect of turbulence on the drag of flat plates

"In determining the effect of turbulence on the forces exerted on bodies in the air stream of a wind tunnel, it is commonly assumed that the indications of the standard Pitot-static tube used to determine the air speed are not dependent on the turbulence. To investigate the truth of this assumption, the drag of a normally exposed flat plate, the difference in pressure between the front and rear of a thin circular disk, the rate of rotation of a vane anemometer, and the pressure developed by a standard Pitot-static tube were measured in an air stream for several conditions of turbulence. The results may be interpreted as indicating that there is no appreciable effect of turbulence on the vane anemometer and the standard pitot-static tube, but that there is small effect on the drag of a flat plate and the pressure difference between front and rear of a disk" (p. 129).
Date: June 22, 1935
Creator: Schubauer, G. B. & Dryden, H. L.
System: The UNT Digital Library
On the Theory of Laminar Boundary Layers Involving Separation (open access)

On the Theory of Laminar Boundary Layers Involving Separation

"This paper presents a mathematical discussion of the laminar boundary layer, which was developed with a view of facilitating the investigation of those boundary layers in particular for which the phenomenon of separation occurs. The treatment starts with a slight modification of the form of the boundary layer equation first published by Von Mises. Two approximate solutions of this equation are found, one of which is exact at the outer edge of the boundary layer while the other is exact at the wall" (p. 541).
Date: May 22, 1934
Creator: von Karman, T. & Millikan, C. B.
System: The UNT Digital Library
Flight tests of the drag and torque of the propeller in terminal-velocity dives (open access)

Flight tests of the drag and torque of the propeller in terminal-velocity dives

From Summary: "The drag and torque of a controllable propeller at various blade-angle settings, and under various diving conditions, were measured by indirect method on F6C-4 airplane in flight. The object of these tests were (1) to provide data on which calculations of the terminal velocity with a throttled engine and the accompanying engine speed could be based and (2) to determine the possibility of utilizing the propeller as an air brake to reduce the terminal velocity. The data obtained were used in the establishment of propeller charts, on the basis of which the terminal velocity and engine speed could be calculated for airplanes whose characteristics fall within the range of these tests."
Date: August 22, 1933
Creator: Rhode, Richard V. & Pearson, Henry A.
System: The UNT Digital Library
The 7 by 10 Foot Wind Tunnel of the National Advisory Committee for Aeronautics (open access)

The 7 by 10 Foot Wind Tunnel of the National Advisory Committee for Aeronautics

This report presents a description of the 7 by 10 foot wind tunnel and associated apparatus of the National Advisory Committee for Aeronautics. Included also are calibration test results and characteristic test data of both static force tests and autorotation tests made in the tunnel.
Date: October 22, 1931
Creator: Harris, Thomas A.
System: The UNT Digital Library