Lift-Curve Slope and Induced Drag Factors of Large Aspect Ratio Straight-Tapered Wings

Extract

The difficulties of computing a solution to the Prandtl lifting line equation for large values of A/a₀ are well-known, at least to any investigators who have tried. In attempting to deduce the loading over straight-tapered wings, like those used on sailplanes, the author has used an iterative method by which the n^th. approximation to the downwash is obtained by a numerical integration based on the (n–l)^th. approximation to the distribution of circulation. The main difficulty here is essentially one of making a good initial guess of circulation for the first approximation to the downwash.