The YJ93 was a single-shaft axial-flow turbojet with a variable-stator compressor and a fully variable convergent/divergent exhaust nozzle.

[1] The YJ93 started life as the General Electric J79-X275, an enlarged version of the General Electric J79 turbojet with "275" meaning Mach 2.75, the engine's target operating speed.

The six YJ93 engines in the XB-70 Valkyrie were capable of producing a thrust to weight ratio of 5:1 allowing for a speed of 2,000 mph (3,200 km/h) (approximately Mach 3) at an altitude of 70,000 feet (21,000 m).

[4] The first engine went on test in September 1958 and featured advanced technology achievements such as electrolytically drilling longitudinal air cooling holes in the turbine blades.

[5] Data from Aircraft engines of the World 1966/77,[8] Military Turbojet/Turbofan Specifications,[9] North American XB-70A Valkyrie[1] Related development