Favorable thickness distributions for wings in supersonic flow.

Abstract

The present paper deals with the problem of wave drag due to thickness in supersonic flow. Pressure distribution and drag of wings with general planform can be evaluated within the accuracy of linearized supersonic theory, under the restriction that the wings have supersonic trailing edges. Thickness distributions are given in the form of double power series of chordwise distance from the leading edge, divided by the local chord, and series of spanwise distance, divided by the semi-span. First, pressure distributions over the wing surface are calculated from the well-known formula and then the drag of the wing is evaluated by integrating the pressure distribution, and finally the optimum wing is determined by fixing the parameters involved to describe thickness distributions. Numerical examples show that a fairly large amount of reduction in drag is possible compared with that of the wing with biconvex section of constant thickness ratio along the span for delta wings. For Gothic wings, only very little reduction in drag seems possible. Reduction in drag is larger for arrow and double delta wings than for delta wings.