Unsymmetrical lift distributions on a stalled monoplane wing

• Main Author: Schairer, Robert Sorg
• Format: Others
• Published: 1939
• Online Access: https://thesis.library.caltech.edu/5153/1/Schairer_r_1939.pdf; Schairer, Robert Sorg (1939) Unsymmetrical lift distributions on a stalled monoplane wing. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/3WX9-JZ33. https://resolver.caltech.edu/CaltechETD:etd-12282005-110200 <https://resolver.caltech.edu/CaltechETD:etd-12282005-110200>

The purpose of the research was to find if it is possible to have an unsymmetrical span load distribution on a monoplane wing at the stall without a rolling velocity. The investigation is based upon the Prandtl first order wing theory. It is shown that it is possible to have an unsymmetrical lift distribution at the stall if a certain shape is assumed for the curve of section lift coefficient vs. effective angle of attack. Two methods of determining such a solution for any particular wing shape are discussed. Curves are presented showing unsymmetrical solutions for a number of different wing shapes and also showing the resulting lift and rolling moment coefficients. The important conclusions are as follows: 1. An unsymmetrical lift distribution across the span of a monoplane wing at the stall is possible. 2. The unsymmetrical solution produces a rolling moment of the same order of magnitude as that caused by a fully deflected aileron. 3. The unsymmetrical distribution can occur only in a very small range of angles of attack after the wing begins to stall. 4. The magnitude of the maximum rolling moment coefficient and the difference between the angle of attack at which the maximum rolling moment occurs and the angle of attack for first stall are nearly the same for all of the wing shapes investigated.