In the latest setback for the Pentagon's nearly $400-billion F-35 Joint Strike Fighter program, the U.S. military has grounded all of the fighter jets from flight operations after one of them caught fire at Eglin Air Force Base in Florida earlier this week.
Flights had been expected to resume the day after Monday's mishap, but the Air Force, Navy and Marine Corps decided to suspend all F-35 operations until it was determined that flights could resume safely.
A safety board has begun investigating the incident to determine the cause.
Early Monday, one of the Air Force's radar-evading, supersonic fighter jets caught fire before takeoff. The pilot left the aircraft uninjured, officials said.
The aircraft was preparing to take off on a training mission but aborted when flames appeared in the rear of the aircraft. Emergency responders extinguished the fire with foam, according to an Air Force statement.
The 33rd Fighter Wing at Eglin provides training for F-35 pilots and mechanics for the Marine Corps, Navy and Air Force. The wing commander there stopped flights as a precautionary measure, but flights continued elsewhere around the country.
More than 100 F-35s are in service at bases around the nation, including Edwards Air Force Base about 100 miles northeast of Los Angeles.
The decision to ground all F-35 flights was made Wednesday afternoon as more information became available, according to F-35 spokeswoman Kyra P. Hawn in the military's Joint Program Office.
"We are grateful that Monday's incident was contained, and that procedures were followed that prevented additional damage or injury," she said.
The Joint Strike Fighter program centered around a plan to develop one basic fighter plane that could — with a few manufacturing tweaks — be used by the Air Force, Navy and Marines. The idea is that it can be configured to take off and land on runways and aircraft carriers, as well as hover like a helicopter.
No one stealthy fighter aircraft has all these capabilities. From an engineering standpoint, it's a challenging task for plane maker Lockheed Martin Corp. because the requirements of the different services vary so much.
"Follow-on activities are providing us with the opportunity to learn how to efficiently and effectively coordinate the flow of relevant information to a diverse group of F-35 stake holders," Hawn said.
The grounding of the F-35 fleet is a blow to the often-troubled program, which has been in development for more than a decade, is billions of dollars over budget and years behind schedule. Per-plane cost estimates have risen from $78 million in 2001 to $135 million today, according to the Government Accountability Office.
Testing is key to the Pentagon's ultimate plan to build 2,457 of the planes.
Problems have repeatedly cropped up. On June 13, test flights were temporarily halted and mandatory inspections were ordered for all versions of the jets after a Marine F-35 suffered an in-flight emergency with its engine.
A Lockheed spokesman said that the company was aware of the incident at Eglin and prepared to provide any assistance requested.