Pratt & Whitney F135 Engine

F135 Background

Pratt & Whitney F135 -- The World's Most Powerful Fighter Engine

Pratt & Whitney's F135 propulsion system is the engine for the new advanced, single-engine tactical fighter, the F-35 Lightning II, developed by Lockheed Martin. The F-35 has unique capabilities for conventional takeoff and landing (CTOL), carrier-variant (CV), and short takeoff and vertical landing (STOVL). The same F135 engine will power all three variants. The F135 propulsion system has already proven that it can meet these diverse requirements as it was chosen by both Lockheed Martin and The Boeing Company as the exclusive power for all Concept Demonstration Aircraft (CDA) Joint Strike Fighter (JSF) flights. More than 17,500 test hours have been completed.

System Development and Demonstration

On October 26, 2001, Pratt & Whitney was awarded a ten year, $4.8 billion (U.S.) contract for System Development and Demonstration (SDD). Under the SDD contract, Pratt & Whitney is developing the F135 propulsion system through flight clearance, flight test, and qualification for Low Rate Initial Production (LRIP). The first LRIP deliveries occurred in 2009.

To date, Pratt & Whitney has delivered 11 ground test engines – five of the five planned CTOL/CV configurations and six of the seven planned STOVL configurations. The company has now delivered 18 flight test engines and amassed more than 17,500 test hours.

Building on a Legacy of Experience

The technologically advanced F135 is an evolution of the highly successful Pratt & Whitney F119, exclusive power for the U.S. Air Force's F-22 Raptor. In March 2009, the F119 achieved a major milestone, surpassing 100,000 operational flight hours. The F135 improves upon the validated F119 core, integrating the F119's high-performance six-stage compressor and single-stage turbine unit with a new low-pressure spool. By the time the F-35 enters operation in 2013, the F119 engines will have logged nearly 500,000 flying hours and the F135 will have logged more than 16,000 test hours.

The F135 propulsion system team consists of Pratt & Whitney, the prime contractor with responsibility for the main engine and overall system integration; Rolls-Royce, providing the lift fan, three-bearing swivel module and roll posts to the STOVL version of the F135; and Hamilton Sundstrand, provider of the F135's control system and gearbox.

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