The General Electric YJ101 was an afterburning turbojet engine, as signified by its "J" designation, in the 15,000 lbf class. It was designed for the Northrop P-530 Cobra,Jane's All The World's Aircraft 1975-76, p.747 but its initial application was the Northrop YF-17 entry in the Lightweight Fighter (LWF) competition. It was subsequently developed into the widely used General Electric F404.
Design Two essential requirements for the engine were reliability, which can be measured by the number of times a particular engine model has to be shut down during flight (in-flight shutdown rate), and handling. This means stall-free operation throughout the entire flight envelope, allowing the pilot to make unrestricted throttle movements anywhere between idle and maximum afterburner.Flight International, 14 April 1984, F404: Fighter pilot's engine, p.1021
The engine used continuous bypass bleed from the compressor to cool the afterburner liner and nozzle. The bypass air was not mixed with hot air from the turbineFlight International, 21 August 1978, "F-18: US Navy Air Combat Fighter", p.262 as the afterburner was a simple turbojet style with no requirement for intentional mixing of the bypass flow with the turbine exhaust. However, mixing is an important requirement for turbofan engines.
General Electric chose to describe the engine differently depending on the circumstances. To emphasize simplicity, it was a "leaky turbojet". For advanced technology, it was "the world's first self-cooled turbojet".The Lightweight Fighter Program:A Successful Approach to Fighter Technology Transition, Aronstein and Piccirillo 1996, , p.42 This referred to using the compressor bypass air to cool the afterburner instead of using much hotter turbine exhaust gas.
Applications
Northrop YF-17
Specifications (YJ101)
See also
References
External links
F404 page on GlobalSecurity.org