Tuesday, October 5, 2010

Pratt & Whitney F119

The Pratt & Whitney F119 is an axial-flow, turbofan engine designed and manufactured by Pratt & Whitney. The F119, or PW5000, powers the F-22 Raptor fighter aircraft. It is the first jet engine developed to fly at supersonic speed without the use of afterburner. The F119 is fitted with two-dimensional pitch vectoring exhaust nozzles, which direct the engine thrust ± 20° in the pitch axis. This feature endows the F-22 Raptor with enhanced maneuverability. Pratt & Whitney's innovative titanium alloy increases stator durability, allowing the engine to run hotter and faster for greater thrust and efficiency. This heat-resistant titanium alloy protects aft components, permitting greater thrust and durability.

The F119 has a maximum thrust of 35,000 lbf, allowing a sustained supersonic speed of Mach 1.75. The three-stage integrally bladed fan of the F119 is powered by a single-stage low-pressure turbine. The engine’s counterrotating core is fitted with an aerodynamically efficient six-stage high-pressure compressor, which is driven by a single-stage high-pressure turbine, featuring the latest single-crystal superalloy blades and advanced cooling technologies. The F119 has been developed into the F135 engine, which power the F-35 fighter aircraft.

Specifications for the Pratt & Whitney F119

Type: axial-flow, twin-spool, turbofan engine
Diameter: 50 in (1,29 m)
Length: 16 ft 11 in (5.16 m)
Dry weight: classified
Compressor: Axial 3-stage low-pressure compressor; 6-stage high-pressure compressor
Combustors: Short, annular combustor
Turbine: single stage high pressure turbine; two stage low pressure turbine
Maximum thrust: more than 35,000 lbf (156 kN), with afterburner
Thrust-to-weight ratio: 9:1