The effect of compressibility on NACA 4412 is discussed in terms of the affect it has on airfoil camber, thickness ratio and angle of attack. Diagrams are given showing how the Prandtl-Glauert is applied. This application involves "stretching" the airfoil in the direction of motion, using the Prandtl-Glauert factor, which is a function of Mach number.
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