FARNBOROUGH, England -- The F-35 fighter jet may take flight here after all.
The U.S. Defense Department said Tuesday that air safety officials had cleared the F-35 Joint Strike Fighter to resume flights after an investigation into an engine fire last month appeared to have ruled out a systemic problem.
Analysts said the move would most likely clear the way for the Pentagon's newest warplane to make its planned debut at the major air show here, even though the root cause of the fire at a base in Florida remains unknown.
The risk of a no-show by the F-35, built by Lockheed Martin, has been the talk of the weeklong Farnborough International Air Show, which began Monday, threatening to overshadow a raft of civilian jet orders from the two industry behemoths, Airbus and Boeing.
The Pentagon's press secretary, Rear Adm. John F. Kirby, called the lifting of the grounding order "an encouraging step" but stressed that no definitive plans had been made to send the jets to Britain.
"Safety remains the overriding priority," Kirby said in a statement.
U.S. military officials said Monday the June 23 fire had been caused by "excessive rubbing" of a turbine blade in the jet's single engine, which is built by Pratt & Whitney. The added friction shattered a fan blade, sparking a fire as the jet accelerated for takeoff from Eglin Air Force Base, the officials said.
Lt. Gen. Christopher C. Bogdan of the U.S. Air Force told journalists that inspections of the entire 97-plane fleet had yielded no signs of similar damage to the turbine blades of any other engines.
There were no injuries reported in the case, which followed a brief grounding of the F-35 fleet in early June after an oil leak forced a Marine Corps pilot to make an emergency landing.
The setbacks follow a series of technical problems and development delays that have dogged the F-35, one of the world's most ambitious weapons programs, with estimated development costs of around $400 billion.