The Pratt & Whitney F135 engine powering the F-35 Lightning II ran up in full-afterburner mode—all 40,000 pounds of thrust—on Sept. 18 during the end of the first series of engine runs at the Lockheed Martin production facility in Fort Worth, Tex. P&W officials say the F135’s 40,000-pound thrust is “the most ever from a jet-fighter engine.” The engine has been through thousands of hours on test stands, but officials said this was the first series of tests on the aircraft and puts the program on the “final stretch leading to first flight” later this year.
The F-35 Joint Program Office has officially announced plans to issue multiple sole-source contracts to Pratt & Whitney to upgrade the fighter’s F135 engine—a widely expected move after Pentagon officials indicated they would do so earlier this year instead of developing an entirely new engine.