The Effect of Compressibility on the Pressure Reading of a Prandtl Pitot Tube at Subsonic Flow Velocity
This is a 1939 technical report from the NASA Technical Reports Server on how air compressibility changes the pressure reading of a Prandtl pitot tube at subsonic speeds, written for aerodynamic engineers and aircraft instrument designers. Its pictures are plain graphs of pressure error against speed and Mach number, plus schlieren photographs of a circular flow field with a shadowed rod across it. A designer might take from them the spare, data-driven look of mid-century engineering plots and the striking light-and-shadow contrast of schlieren imagery.
