Properties of low-aspect-ratio pointed wings at speeds below and above the speed of sound (open access)

Properties of low-aspect-ratio pointed wings at speeds below and above the speed of sound

"Low-aspect-ratio wings having pointed plan forms are treated on the assumption that the flow potentials in planes at right angles to the long axis of the airfoils are similar to the corresponding two-dimensional potentials. For the limiting case of small angles of attack and low aspect ratios the theory brings out the following significant properties: (1) The lift of a slender, pointed airfoil moving in the direction of its long axis depends on the increase in width of the sections in a downstream direction. Sections behind the section of maximum width develop no lift. (2) The spanwise loading of such an airfoil is independent of the plan form and approaches the distribution giving a minimum induced drag. (3) The lift distribution of a pointed airfoil travelling point-foremost is relatively unaffected by the compressibility of the air below or above the speed of sound. A best of a triangular airfoil at a Mach number of 1.75 verified the theoretical values of lift and center of pressure" (p. 1).
Date: May 11, 1945
Creator: Jones, Robert T.
System: The UNT Digital Library
Properties of low-aspect-ratio pointed wings at speeds below and above the speed of sound (open access)

Properties of low-aspect-ratio pointed wings at speeds below and above the speed of sound

Low-aspect-ratio wings having pointed plan forms are treated on the assumption that the flow potentials in planes at right angles to the long axis of the airfoils are similar to the corresponding two-dimensional potentials.
Date: May 11, 1945
Creator: Jones, Robert T.
System: The UNT Digital Library
Comparison of wind-tunnel and flight measurements of stability and control characteristics of a Douglas A-26 airplane (open access)

Comparison of wind-tunnel and flight measurements of stability and control characteristics of a Douglas A-26 airplane

From Summary: "Stability and control characteristics determined from tests in the Langley 19-foot pressure tunnel of a 0.2375-scale model of the Douglas XA-26 airplane are compared with those measured in flight tests of a Douglas A-26 airplane. Agreement regarding static longitudinal stability as indicated by the elevator-fixed neutral points and by the variation of elevator deflection in both straight and turning flight was found to be good except at speeds approaching the stall. At these low speeds the airplane possessed noticeably improved stability, which was attributed to pronounced stalling at the root of the production wing."
Date: August 11, 1945
Creator: Kayten, Gerald G. & Koven, William
System: The UNT Digital Library