Comparison of locked-rotor and windmilling drag characteristics of an axial-flow-compressor type turbojet engine

The internal drag of an axial-flow turbojet engine with the rotor locked in place to prevent windmilling and with the engine windmilling was obtained over a range of simulated Mach numbers. The corrected internal drag of the engine with the locked rotor was 210 pounds or only 46 percent of the windmilling drag at a flight Mach number of 0.8.