In late 1953, General Electric began a design study of a high thrust-to-weight ratio turbojet engine. The prototype J85 engine ran in January 1956, the first flight was in August 1958 as the power plant of the McDonnell GAM-72 missile, and in September 1958 the prototype North American T-39 Sabreliner flew for the first time powered by the first man-rated J85 engines.
The J85 was the first U.S. small turbine engine to go into production with an afterburner. The most important applications were the Northrop T-38 Talon, the first supersonic trainer, and Northrop F-5 Freedom Fighter, a low-cost fighter used by many nations from the 1960s through the 1980s. The non-afterburning J85-GE-17A powered the Cessna A-37A/B attack aircraft. The J85 had the highest thrust-to-weight ratio of production engines built for its time (up to 7.3:1 on the J85-GE-21). GE built more than 12,000 J85 engines before production ended in 1988.
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.