Ramjet
As the compression of the inlet raises with speed the compression of the first compressor stage is reduced accordingly. The afterburner behind a turbine runs with a stoichiometric mixture like a ramjet but at higher pressure and thus more efficiency than a pure ramjet. It is claimed that an inlet at Mach 3.5 produces the same compression (44:1 ) as the whole compressor of a jet engine at zero speed, so the turbine should be bypassed then.
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