A 2-D method is described which combines supersonic and subsonic linear lifting surface theories, both based on the velocity potential panel ajproach, while at the same time the effect of the moving shock is taken into account. For a NACA 64A006 airfoil transonic results are presented in comparison with results of an improved version of the LTRAN2 code, developed at NLR. The good agreement obtained shows the feasibility of the method, while the low computer cost makes this approach very attractive. Presented at the AIAA/ASME 21ste Structures, Structural Dynamics & Materials, Conference, Seattle, Washington, May 12-14, 1980.