Wave drag of wings at supersonic speeds

Abstract

The existing method of calculating the wave drag of wings at supersonic speeds is very laborious. It involves evaluating a double integral to find the velocity potential, differentiating this potential to find the pressure coefficient, and finally evaluating another double integral for the drag. It is shown that it is possible to write down a quadruple integral giving the drag directly. This quadruple integral is best evaluated by calculating a geometric distribution function S(ζ); the drag can then be obtained from S(ζ) by a single integration. For wings with plane facets separated by sharp bend lines, the evaluation of S(ζ) is particularly simple, and some examples axe given. The method is also applicable to the calculation of lift distributions on wings with purely supersonic edges. This topic is briefly explored in an appendix.