Essentially an enlarged version of the earlier Westinghouse J30, the J34 produced 3,000 pounds of thrust, twice as much as the J30.

Built in an era of rapidly advancing gas turbine engine technology, the J34 was largely obsolete before it saw service, and often served as an interim engine.

The Stiletto was developed to investigate the design of an aircraft at sustained supersonic speeds.

However, equipped with the J34 instead of its intended engines, it was seriously underpowered and could not exceed Mach 1 in level flight.

[2] Developed during the transition from piston-engined aircraft to jets, the J34 was sometimes fitted to aircraft as a supplement to other powerplants, as with the Lockheed P-2 Neptune and Douglas D-558-2 Skyrocket (fitted with radial piston engines and a rocket engine, respectively).