The Pratt & Whitney J75 was first announced in 1954. It was developed from Pratt & Whitney's J57 engine with similar component arrangement, but having entirely new design features emphasizing weight control, and resulting in significantly lower specific weight. Production began in the spring of 1957, and both afterburning and nonafterburning versions were produced. The commercial version of the J75, known as the JT4, was certificated in March 1957.

The J75 powered the first U.S. operational Mach 2 fighter-interceptor, the Convair F-106 Delta Dart, and the Republic F-105 Thunderchief fighter-bomber, Lockheed U-2A reconnaissance aircraft, and North American F-107A. The JT4 was used on the Boeing 707-220/-320 and the McDonnell Douglas DC-8-20/-30 airliners. This J75-P-2, powered the Martin P6M-2 Seamaster flying boat.

 Display Status

This object is not on display at the National Air and Space Museum. It is either on loan or in storage.
Object Details
Date 1957 Country of Origin United States of America Type PROPULSION-Turbines (Jet) Manufacturer Pratt & Whitney
 Physical Description Type: Turbojet Thrust: 75,600 N (17,000 lb) Compressor: 16-stage, 2 spool axial Combustor: Cannular Turbine: Single-stage high pressure and 2-stage low pressure axial Weight: 2,277 kg (5,020 lb) Dimensions Length 481 cm (189.2 in.), Diameter 109 cm (43.0 in.)
 Inventory Number A19700093000 Credit Line Transferred from the U.S. Navy, Naval Supply Center, Cheatham Annex, Williamsburg, Virginia Data Source National Air and Space Museum Restrictions & Rights Usage conditions apply
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