P&W conventional take off and landing-carrier variant F135 engine receives initial service release

Pratt & Whitney has achieved initial service release (ISR) for the conventional take off and landing/carrier variant (CTOL/CV) F135 engine, marking another major milestone as the engine is cleared for operational use in the Lockheed Martin F-35 stealth fighter. Pratt & Whitney has delivered 17 flight test engines, as well as the first production F135 engine, and expects to deliver the final short take off and vertical landing (STOVL) flight test engine early this year.