From the preceding investigation, it may be concluded that the method of calculating subsonic compressible flows proposed by Gelbart is valid and practical for arbitrary airfoil shapes for which a convenient mapping function exists, It was found that the method can be carried out with comparative ease as compared to numerical methods of solution and therefore lends itself to engineering use. A particular advantage of the method is that it allows the approximate solution of the direct problem, that is, the flow about a given body at a prescribed angle of attack and freestream Mach number.