Method of Selecting the Thickness, Hollowness, and Size of a Supersonic Wing for Least Drag and Sufficient Bending Strength at Specified Flight Conditions

摘要

This paper considers a wing-selection problem sometimes encountered in the preliminary design of supersonic airplanes and missiles. The problem is to determine the span, section thickness ratio, and skin thickness or hollowness ratio of the wing of least drag when the plan form, section shape, wing lift requirement, and flight conditions are assumed known. The only structural requirement considered in the analysis is that of bending stress which is assumed to be carried entirely by the skin. An analytical method is presented by means of which the optimum wing dimensions can readily be obtained. An example of the application of the method to a diamond wing at Mach number 2.0, for a range of specified flight conditions, is presented. From this example, for supersonic flight at low altitudes, steel wings appear to have appreciably less drag than aluminum wings; whereas, for high altitudes, the reverse appears to be true. It is concluded from the example that wings with thickness ratios, hollowness ratios, or chords appreciably different from those given by the present method may have considerably higher drags.