Completes Initial Service Release Altitude Qualification Test

The Pratt & Whitney's F135 engine powering the F-35 Joint Strike Fighter has completed altitude qualification ground testing, the final testing that demonstrates the operability and performance required for Conventional Take-off and Landing (CTOL) and Carrier Variant (CV) Initial Service Release (ISR). ISR is the U.S. Government's recognition that the F135 engine is ready for operational use and clears Pratt & Whitney to deliver and field production F135 engines.

"I'm very proud of the Pratt & Whitney F135 engine team and the test team at Arnold Engineering Development Center in Tennessee for their efforts in completing this critical milestone, not just for the F135 engine but for the entire F-35 program," said Warren Boley, Vice President of F135 Engine Programs at Pratt & Whitney. "Their hard work has demonstrated the performance of the F135 engine and puts us at the doorstep of achieving ISR."

The most recent testing, which included a total of 126 test hours, evaluated the F135 engine's air start capability and augmentor performance, as well as demonstrated and proved the performance of critical systems such as in-flight throttle response, inlet compatibility, engine ice protection and combustor stability. The final test period was also a testament to the reliability of the F135 engine and, at 38.7 hours, was the longest continuous test period completed to date on the F135 program.

The F135 System Development and Demonstration (SDD) program surpassed 12,850 hours of engine test time, successfully completed 90 CTOL flights, and completed 125 hours of flight time. Missions have included augmented takeoffs, supersonic flight, in-flight cycling of weapons bay doors, air-to-air refueling, in-flight engine restarts, and cross-country flights to and from Eglin and Edwards Air Force bases.

FMI: www.pratt-whitney.com