Gerald E. Nitzberg, Stewart Crandall
naca-tn-1813
Feb 1949
A study of experimental pressure distributions and section characteristics for several moderately thick airfoil sections was made. A correlation appears to exist between the drag-divergence Mach number and the free-stream Mach number for which sonic velocity occurs at the airfoil crest, the chordwise station at which the airfoil surface is tangent to the free-stress direction.
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