The Pentagon has grounded all 79 F-35 fighter jets because of concerns arising from its probe of a June 23 runway fire that forced a pilot of one of the aircraft to abort takeoff at Eglin Air Force Base in Florida.
While the Pentagon said the root cause of the fire in the plane's rear is still under investigation, air-worthiness officials with the Air Force and the Navy ordered additional inspections of F-35 engines.
The troubled fifth-general jet fighter is manufactured by Lockheed Martin, with its engine made by Pratt & Whitney.
Different military services have their own versions of the F-35. The Air Force grounded its planes last week within days of the June 23 fire. The Pentagon decision Thursday removes the Navy and Marine Corps versions of the jet from service.
All of the 79 F-35s located at U.S. military bases are still being used for test flights, with the Marine Corps planning to bring its F-35B version into its operational fleet by the end of next year.
Already the costliest weapons system in U.S. history with a projected price tag of almost $400 billion for 2,443 aircraft planned for production, the F-35 Joint Strike Fighter has been plagued by a series of software and hardware problems, including bulkhead cracks, since manufacturing began in 2006. The cost has risen 70 percent in inflation-adjusted dollars since design started in 2001.
In a separate incident, an oil leak last month during the flight of an F-35 from Marine Corps Air Station Yuma in Arizona prompted the Pentagon to order mandatory engine inspections and ground the fleet temporarily.
Defense analysts say some of the problems are the result of starting to manufacture the high-tech jet fighters while its design was still being completed.
NATO members and other U.S. allies have paid for some of the F-35's development costs. Six countries, all members of the Western military alliance, have ordered from two to 72 of the aircraft, but only Britain's Royal Air Force has any in use, with three also in testing phase. Israel, Canada, Japan and South Korea have announced plans to purchase between 40 and 75 of the jets.
The Pentagon said it will decide next week whether the F-35 can participate as scheduled in two international airshows in the United Kingdom later this month.
By James Rosen
McClatchy Washington Bureau