This was Garrett's first turboprop engine, and a key first-generation turbine engine that significantly improved performance and utility of general aviation, executive and commercial commuter aircraft. From a technical perspective, it was noteworthy for its short and compact configuration, low installed weight and drag, good specific fuel consumption, aerodynamic efficiency, and performance.
In 1964, the company's YT76 turboprop version of the TSE331 generator set was selected for the North American OV-10A counter insurgency aircraft, and entered Viet Nam War service in 1968.
Garrett simultaneously developed a commercial version of the engine, for which the launch customer was the Mitsubishi MU-2 transport. Over time a number of more powerful TPE331 models were developed for general aviation aircraft such as the Beech B100 King Air, Cessna Conquest 441, Commander Series, Piper Cheyenne IV, and Mitsubishi Solitaire/Marquise. Commuter aircraft applications included the Fairchild Merlin and Metro, BAe Jetstream 31 and Super 31, CASA 212, and Shorts Skyvan 3.
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.