Problems involving discontinuous aerodynamic twist, as for a flapped wing, are not readily soluble for wings having a rectangular plan form or straight taper. Lotz's method (B.Ae.S. Journal, May, 1934) has been stated to be particularly suitable, but a recent American report used in preference a direct method of successive approximation. In either case a fair amount of labour is involved, and the final results are only approximate. The exact solution for a wing of elliptic plan form, whilst no-t directly applicable to the usual type of tapered monoplane wing, is readily obtainable, and should give a good idea of the lift distribution and induced drag due to a flap on an actual wing.