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History

The F119 resulted from the Joint Advanced Fighter Engine (JAFE) program in the early 1980s aimed at supplying the powerplant for the Air Force's Advanced Tactical Fighter (ATF). Detailed design of Pratt & Whitney's submission, designated internally as PW5000, began when the request for proposals (RFP) for JAFE, later renamed the ATF Engine (ATFE) program, was released in May 1983. Advances in engine technology, such as those from the Advanced Turbine Engine Gas Generator (ATEGG) and the Joint Technology Demonstration Engine (JTDE) programs, allowed the design to do more work with fewer stages, with the PW5000's compressor having only 6 stages compared to the 10 stages in the F100's compressor. The high pressure and low pressure turbines were single stage and counter-rotating, which reduced the gyroscopic forces on the engine; it was hoped that counter-rotation would eliminate a row of turbine stators for a vaneless high and low pressure turbine interface, which would save weight and reduce parts count, but this was ultimately not successful and the stators were retained. The fan and compressor stages were to use integrally bladed rotors (IBR), also known as blisks, to reduce weight and cost and improve performance. Owing to the ATF's demanding requirements for supercruise, the PW5000 design has low bypass ratio, high core and turbine inlet temperatures, and a fully variable convergent-divergent nozzle to achieve high specific thrust in intermediate, or non-afterburning power. The combustor, internally named Floatwall, eliminated welds to mitigate crack growth due to thermal cycling. The original RFP called for maximum thrust in the 30,000 lbf (133 kN) class for an aircraft gross weight of 50,000 lb (22,700 kg).

Pratt & Whitney and General Electric were selected to make prototype engines, designated YF119 and YF120 respectively, for demonstration and validation (Dem/Val). Both engine makers would provide engines for both the Lockheed/Boeing/General Dynamics YF-22 and the Northrop/McDonnell Douglas YF-23 ATF technology and flight demonstrators. The ATF's increasing weight during development required more thrust to meet the performance requirements; as gross weight grew to 60,000 lb (27,200 kg), the required maximum thrust was increased by 20% to 35,000 lbf (156 kN) class. Pratt & Whitney's design changed to incorporate a 15% larger fan, increasing bypass ratio from 0.25 to 0.30. However, unlike General Electric, Pratt & Whitney did not fit its larger fan on flightworthy YF119s for the ATF flight demonstrators to avoid potential reliability issues that may arise. Instead, the revised fan was extensively ground tested at Wright-Patterson Air Force Base. As a result, both the YF-22 and YF-23 had lower performance with the YF119s than with the YF120s.

On 3 August 1991, Pratt & Whitney was awarded the EMD contract for ATF engine, while the Lockheed/Boeing/General Dynamics team won the contract for the ATF airframe. While the YF119 was a more conventional design compared to the General Electric's variable cycle YF120, Pratt & Whitney accrued far greater test hours and emphasized reliability and the lower risk. Ground tests of the F119-PW-100 were first conducted in February 1993. The production engines were fitted on the production F-22, and were first flown on the F-22's maiden flight on 7 September 1997. A total of 507 engines were produced. In 2013 Pratt & Whitney assisted the F119 Heavy Maintenance Center (HMC) at Tinker Air Force Base, Oklahoma in the first F119 depot overhaul.

Turbine engine advances from ATEGG and JTDE continued with the Integrated High Performance Turbine Engine Technology (IHPTET) program, with applications in F119 improvement packages and derivatives. Prototype YF119 variants powered the Boeing X-32 and Lockheed Martin X-35 Joint Strike Fighter (JSF) concept demonstrator aircraft, and subsequent full scale development of the F119 derivative resulted in the F135 family of engines that powers the Lockheed Martin F-35 Lightning II.