A US Air Force F-35 jet caught fire last month while preparing for take-off

All US F-35s grounded pending engine inspections

The US military has grounded the entire fleet of 97 Lockheed Martin F-35 fighter jets until completion of additional inspections of its single engine.

The engine, built by Pratt & Whitney, a unit of United Technologies, may have been involved in an accident that saw an F-35 catching fire on 23 June shortly before take-off at Eglin Air Force Base in Florida.

"Additional inspections of F-35 engines have been ordered, and return to flight will be determined based on inspection results and analysis of engineering data," the Defense Department said in a brief statement issued late on Thursday.

Pratt & Whitney said it was working closely with Air Force officials who are investigating the fire and are inspecting all engines in the fleet. Spokesman Jay DeFrank said it would be inappropriate to comment further since the incident was the subject of an investigation.

The cause of the accident, which saw the plane’s pilot escaping without injury, has not yet been determined.

The incident is the latest to hit the Pentagon's costliest weapons program, the $398.6bn  (£232.48bn) F-35 Joint Strike Fighter.

It followed an in-flight oil leak that triggered mandatory fleetwide inspections of the jets last month.

The Pentagon's F-35 program office has made determining the cause of the fire its highest priority and it is assessing the impact on flight tests, training and operations of the radar-evading warplane.

A person familiar with the situation said it was premature to rule in or out any quality problem or manufacturing defect.

The accidents may impact sales of F-35 to other countries. Japanese Defence Minister Itsunori Onodera said he would discuss the F-35 problem during his upcoming visit to the US next week.

"On my coming trip to the US I plan to be reviewing troops and will have a chance to discuss the F-35 development on the ground," Onodera said. "I'd like to confirm the details of this accident."

Japan has ordered 42 of the single-engine stealth jets that will be assembled locally by Mitsubishi Heavy Industries, maker of the World War II-era Zero fighter. Tokyo may order more F-35s when it decides the future of 100 of its older F-15s.

Australia and South Korea said there had been no change to their plans to buy the fighter jets. Australia plans to buy 58 of the fighters and South Korea intends to buy 40.

"To date the JSF aircraft has accrued 15,000 flight hours while the F135 engine has successfully completed nearly 32,000 hours of testing," a spokesman for Australia's Defence Minister David Johnston said.

"Single engine fighters are operated by many air forces and Defence remains confident the F-35 JSF will be reliable and safe."

Reuters reported on Wednesday that US and British authorities were preparing directives ordering a mandatory engine inspection estimated to take about 90 minutes.

British officials remained part of the discussions with US officials and concurred with the US recommendation to ground the jets, pending further inspection results, the F-35 program office said.

The Pentagon said preparations were continuing for F-35 jets to participate in two UK air shows later this month, but a final decision would be made early next week. The fire has already derailed plans for an F-35 jet to fly by a naming ceremony for Britain's new aircraft carrier on Friday.

F-35 infographic

F35 stealth fleet grounded

Recent articles

Info Message

Our sites use cookies to support some functionality, and to collect anonymous user data.

Learn more about IET cookies and how to control them