An experimental investigation at supersonic speeds of the characteristics of two gothic wings, one plane and one cambered

Abstract

Tests have been made at supersonic speeds up to M=2.0 on a thick cambered gothic wing of aspect ratio 0.75, together with tests on the uncambered wing of the same plan-form and thickness. The camber was designed to give attached flow all along the leading edge, and over the whole wing, at one lift coefficient, together with low drag at this lift. The thickness distribution was chosen' to have low zero-lift drag and also to eliminate the adverse pressure gradients due to incidence and camber at the design lift. The results show that the drag of the cambered wing is close to the theoretically estimated value at the design lift coefficient: the drag of the plane wing, however, is also of the same magnitude and the reasons for this are discussed. Other properties of the wings are not in agreement with the slender thin wing theory. At the design condition on the cambered wing the flow is attached over the whole wing. Off-the-design condition the leading edge separations on the cambered wing are much weaker than on the plane wing.