Use of Constant Diffuser Mach Number as a Control Parameter for Variable-Geometry Inlets at Mach Numbers of 1.8 to 2.0

Memorandum presenting an analysis to determine the feasibility of using a constant diffuser Mach number to position a translating spike for optimum inlet performance. A control system incorporating this concept was investigated on a blunt lip, translating-spike inlet at flight Mach numbers of 1.8 to 2.0 and angles of attack up to 6 degrees. Results regarding inlet characteristics and performance with control are provided.