F-35 Fix

Pratt & Whitney believes it is getting closer to solving a mechanical issue that caused an Air Force F-35A fighter jet to catch fire at Eglin Air Force Base, FL, in June.

The mishap incident grounded the Joint Strike Fighter fleet for nearly two weeks in July and caused the Marine Corps F-35B jets to miss their scheduled international debut in England.

This week, a Pratt spokesman confirmed the company is testing a potential solution.

“We have a potential fix that we believe will eliminate the problem and we will conduct engine and rig tests next month to verify that with the services and the [F-35] joint program office,” Pratt spokesman Matthew Bates said in an email. His comments were first reported by Defense News.

Speaking to InsideDefense.com Aug. 29, F-35 joint program office spokesman Joe DellaVedova said Pratt has been working to develop a solution at its facility in West Palm Beach, FL.

“They've been working on ensuring they get the measurements they need and ensuring things will work,” he said. He said testing of the technical solution will continue through September.

DellaVedova confirmed the F-35 fleet, which includes around 100 Air Force, Navy and Marine Corps aircraft, continues to operate under a restricted flight envelope while a root-cause examinations of the mishap engine continues. Those flight rules have been relaxed slightly for the 20 F-35 test aircraft to limit delays to the Marine Corps' schedule for achieving initial operational capability.

Right now, all aircraft are cleared to fly to Mach 1.6 and 3.2G normal acceleration with an angle of attack of 18 degrees. The aircraft require a borescope engine inspection every three hours of flight, whereas the test aircraft can fly for six hours between inspections for weapons testing and aerial refueling missions.

Defense Department officials have said the engine fire was an isolated incident associated with excess rubbing of the fan blades in the hot section of the engine.