The Pratt & Whitney J48 (company designation JT7 Turbo-Wasp) is a

turbojet The turbojet is an airbreathing jet engine which is typically used in aircraft. It consists of a gas turbine with a propelling nozzle. The gas turbine has an air inlet which includes inlet guide vanes, a compressor, a combustion chamber, and ...

engine developed by

Pratt & Whitney Pratt & Whitney is an American aerospace manufacturer with global service operations. It is a subsidiary of Raytheon Technologies. Pratt & Whitney's aircraft engines are widely used in both civil aviation (especially airlines) and military aviat ...

as a license-built version of the Rolls-Royce Tay. The Tay/J48 was an enlarged development of the

Rolls-Royce Nene The Rolls-Royce RB.41 Nene is a 1940s British centrifugal compressor turbojet engine. The Nene was a complete redesign, rather than a scaled-up Rolls-Royce Derwent"Rolls-Royce Aero Engines" Bill Gunston, Patrick Stephens Limited 1989, , p.111 w ...

(Pratt & Whitney J42).

Design and development

In 1947, at the behest of the

United States Navy The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage ...

, Pratt & Whitney entered into an agreement to produce the

centrifugal-flow turbojet engine under license as the J42 (company designation JT6), for use in the

Grumman F9F Panther The Grumman F9F Panther is one of the United States Navy's first successful carrier-based jet fighters, as well as Grumman’s first jet fighter. A single-engined, straight-winged day fighter, it was armed with four cannons and could carry a w ...

fighter aircraft.Connors, p.202 Concerned that the Nene would not have the potential to cope with future weight growth in improved versions of the Panther,

Luke Hobbs ''Fast & Furious (also known as The Fast and the Furious)'' is an American action film series centered on a series of action films that are largely concerned with street racing, heists, spies, and family. The following is a list of character ...

, vice president of engineering for P&W's parent company, the

United Aircraft Corporation The PJSC United Aircraft Corporation (UAC) () is a Russian Aerospace manufacturer, aerospace and Arms industry, defense corporation. With a majority stake belonging to the Russian government, it consolidates Russian private and state-owned Russian ...

, requested that

Rolls-Royce Rolls-Royce (always hyphenated) may refer to: * Rolls-Royce Limited, a British manufacturer of cars and later aero engines, founded in 1906, now defunct Automobiles * Rolls-Royce Motor Cars, the current car manufacturing company incorporated in ...

design a more powerful engine based on the Nene, which Pratt & Whitney would also produce. By 1948, Rolls-Royce had designed the Tay turbojet, also a centrifugal-flow design. However, as Rolls-Royce was then developing an improved design with an axial compressor, which would become the Avon, the development and production of the Tay turbojet was left to Pratt & Whitney.Gunston 2006, p.195. However, Rolls-Royce retained the rights to the Tay outside of the United States. The Tay/J48 was a thirty percent enlargement of the preceding Nene/J42, and was produced both with and without

afterburning An afterburner (or reheat in British English) is an additional combustion component used on some jet engines, mostly those on military supersonic aircraft. Its purpose is to increase thrust, usually for supersonic flight, takeoff, and combat ...

Operational history

Several aircraft types used the J48 engine during the 1950s, including the Grumman F9F-5 Panther. and Grumman F9F-6/F9F-8 Cougar, The

U.S. Air Force The United States Air Force (USAF) is the air service branch of the United States Armed Forces, and is one of the eight uniformed services of the United States. Originally created on 1 August 1907, as a part of the United States Army Signal ...

Lockheed F-94C Starfire The Lockheed F-94 Starfire was a first-generation jet powered all-weather, day/night interceptor of the United States Air Force. A twin-seat craft, it was developed from the Lockheed T-33 Shooting Star trainer in the late 1940s. It reached ope ...

RAF Flying Review "TECHNICAL GEN" authors: staff, September 1962 p. 59 and

North American YF-93 The North American YF-93 was an American fighter development of the F-86 Sabre that emerged as a radically different variant that received its own designation. Two were built and flown before the project was eventually canceled. Design and de ...

used afterburning versions of the J48 engine.North American YF-93A
National Museum of the US Air Force fact sheet. Accessed 2017-07-16

Variants

''Data from The Engines of Pratt & Whitney: A Technical History.''Connors, p.210 ;J48-P-1: dry, thrust with

;J48-P-2: , thrust with water injection ;J48-P-3: , thrust with afterburning ;J48-P-5: , thrust with afterburning ;J48-P-6: , thrust with water injection ;J48-P-6a: , thrust with water injection ;J48-P-7: , thrust with afterburning ;J48-P-8: thrust ;J48-P-8A: thrust ; Turbo-Wasp JT-7: Commercial engines / company designation

Applications

* Grumman F9F-5 Panther * Grumman F9F-6/-8 Cougar *

Specifications (J48-P-8A)

References

;Notes ;Bibliography * * * *

External links

Pratt & Whitney History page on the J48
{{DEFAULTSORT:Pratt and Whitney J48

Tay Tay may refer to: People and languages * Tay (name), including lists of people with the given name, surname and nickname * Tay people, an ethnic group of Vietnam ** Tày language *Atayal language, an Austronesian language spoken in Taiwan (ISO 639 ...

1940s turbojet engines Centrifugal-flow turbojet engines