Pratt & Whitney will deliver the last of 507 F119 afterburning turbofans to the US Air Force on 17 January. Two such engines, which the company says have an output in the 35,000lbs (154kN) class each, power the Lockheed Martin F-22 Raptor air superiority fighter.

Though the last Raptor was delivered to the USAF in May 2012, the service ordered additional engines to sustain the F-22 fleet into the future, says Bennett Croswell, president of Pratt and Whitney's military engines division. "When they saw the end of the production line coming, the air force ordered an additional 39 spare engines," he says. "So that's what we've been delivering over the last year."



Like the production tooling for the F-22 airframe, much of the F119 production line is being packed up so that it can be stored at the Sierra Army Depot in California. "That'll be the tooling we're not using in support of the engine," Croswell says. "There'll be some of the tools that we'll retain as we deliver spare parts to support sustainment of the engine in the field."

The F119 shut-down plan does not require preserving assembly and manufacturing knowledge to the degree needed for the Raptor airframe because the many of the same techniques and procedures are being used on Pratt & Whitney's F135 engine, Croswell says. The F135, which powers the Lockheed F-35, is a derivative of the F119. "There is so much similarity between the F135 and the F119, so much we learned on the twin-engine F-22/F119 and we passed onto the single-engine F-35," he says.

Additionally, spare parts will continue to be produced for the F119, Croswell says. But the F119 is going to be regularly overhauled, which means workers will preserve their experience by assembling and dissembling engines. "We just produced the first full depot overhaul of the F119 at Oklahoma City," Croswell says. "So as we continue to disassemble and resemble engines as we overhaul engines, a lot of those skills will be retained."

Additionally, Pratt & Whitney's overhaul and repair capabilities are robust enough that even a severely damaged engine can be repaired and put back into service. "As an example, if you had a bird strike, you would do a lot of damage to the front of the engine-the fan and the compressor, so we deliver spare fan and compressor integrally-bladed rotors to the air force," Croswell says. "That engine would come into the depot and we would replace the damaged parts and return it to the field."

As new technology from the F135 becomes available, more advanced components could be retrofitted to the F119 as the engines are overhauled if the USAF so chooses. "We will continue to have a component improvement programme for the F119," he says. "Just as we put technology back into our F100 engines, we could do the same sort of things for the F119 engine."

If the USAF needs to build more engines, restarting F119 production is technically feasible, Croswell adds.

Source: Flight International