Fixing the F135

Engineers are “very, very close” to conclusively determining the root causes of why an F135 engine started a fire in an F-35 strike fighter in June, and a decision on various fixes will likely be final by the end of October, said F-35 Program Executive Officer Lt. Gen Christopher Bogdan on Monday. He told an audience at AFA’s Air & Space Conference outside of Washington, D.C., that the fix is proceeding along several lines, and some combination of “six options” will resolve the situation. The options revolve around fixing the problem in new-build F135 engines—by potentially changing material that engine mounts rub against—and retrofitting some 150 extant motors, by gradually letting them “burn in,” by performing certain maneuvers in the aircraft, said Bogdan. Pratt & Whitney, F135 maker, will pay for the fixes, he noted. In an interview with Air Force Magazine after his speech, Bogdan said “I don’t think it will be a massive cost,” and will be driven more by touch labor than by replacing parts. P&W military engines chief Bennett Croswell, in a separate briefing for the press on Monday, noted that “we will validate the root causes [of the incident] by the end of the month,” and that of all F135 engines, only three have been found with a similar problem brewing. The company is on a “path to a solution … in six months,” he said. He also pointed out that the F135 is performing very well otherwise, “way above the maturity curve” of any previous fighter engine.