J75 (JT4)

Pratt & Whitney's success with the axial flow, dual-spool design led to the development of the higher thrust J75 engine, rated at 26,500 pounds of thrust with afterburning. It powered the F-105, the F-106 Delta Dart and an advanced U-2 model. The commercial version, the JT4, powered upgraded models of 707 and DC-9 aircraft.

First flight: 1955
Production years: 1956-1967