A new method for determining the steady and unsteady pressure distributions on lifting surfaces is presented. The method employs a "generalized lift-operator" technique which is found to be a more accurate, versatile, and rapid procedure (requiring less computer time) for inverting the downwash integral equation than the presently used "mode-collocation" method. The generalized lift-operator technique allows the chordwise integration to be carried out analytically, thereby avoiding the difficulties in the presently used method. This new approach has been applied to several two-dimensional, unsteady airfoil problems to demonstrate compatibility with known explicit solutions. Numerical solutions for two rectangular foils of aspect ratio 1 and 2 are also presented. The values show good agreement with experiment and fit in with known trends.
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