An Assessment of the Accuracy of Subsonic Linearized Theory for the Design of Warped Slender Wings

SUMMARY A series of warped slender wings has previously been designed using the linearized theory of subsonic flow, as a basis for a systematic experimental investigation of the drag reduction obtainable by warp at low speeds. The force measurements on these wings have now been supplemented by measurements of the pressure distribution over one of them; and the pressure distribution on it has also been calculated for inviscid incompressible flow by a surface-singularity method. This Report compares the distribution of pressure used in the design with those measured and calculated for the design incidence, at which the flow was attached; and assesses the validity of the linear theory. The chief weaknesses are found to be on the thicker cross-sections near the apex, and towards the trailing edge where boundary-layer effects become significant.