The F135 engine, a derivative of the company's F119 engine, powers the F-35 Lightning II Joint Strike Fighter aircraft flight-test program.
Pratt & Whitney announced the F135 engine surpassed the 100 hours of flight testing, which officials said marks a significant step forward for the propulsion system.
"This is a major achievement in a long and growing list of milestones for the F135 team," Bill Gostic, Pratt & Whitney F135 Engine Program vice president, said in a statement.
"It reinforces the reliability and dependability our engine is providing to the Joint Strike Fighter flight test program."
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