Patent ID: 8662453

Claim:
A method of controlling a location of shock waves generated at a leading edge of an engine intake of an engine in a powerplant of a supersonic vehicle, the engine intake comprising a surface providing the leading edge and a cowl having a cowl lip downstream of the leading edge, so that the shock wave extends in an optimum orientation relative to the cowl lip, the method comprising: downstream of the leading edge and upstream of the cowl lip, injecting air into an air flow captured by the air-intake, the air being injected through or adjacent the surface providing the leading edge in a direction neither parallel nor substantially parallel to the air flow, and under sufficient pressure for the injected air to penetrate into the captured airflow, whereby a region of separated flow and a shear layer are formed in the captured airflow for controlling effective shape of the compression surfaces of a supersonic engine intake, and wherein at least one of the direction and the pressure of injection is controlled depending on the velocity of the vehicle so that the shock wave extends in an optimum orientation relative to the cowl lip for optimising the associated shock system geometry.