We have developed four principal examples to illustrate how the method of designing shockless transonic airfoils works in practice. They took varying numbers of test runs of the program to produce, with the earliest case requiring hundreds of trials, but the later ones needing less as we gained experience. All models were designed to have a maximum thickness-chord ratio T/C for given free stream Mach number M∞ and lift coefficient CL, subject to the constraints that the boundary layer not separate far from the tail, that the flow remain safely subsonic along the lower surface, and that the profile be reasonably smooth and blunt at the nose. In all cases we assumed that these desiderata could be achieved best by locating the tail in the hodograph plane at a point where the pressure coefficient Cp would be as near as possible to zero.
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