While the F-35 Lightning II joint strike fighter has returned to limited flying, it will not be appearing at the Farnborough International Airshow in the United Kingdom, Pentagon Press Secretary Navy Rear Adm. John Kirby said during a Pentagon news conference July 15.
The F-35 fleet was grounded July 3 in the wake of a June 23 engine fire on the runway at Eglin Air Force Base, Fla. Navy and Air Force airworthiness authorities recommended the F-35′s return to flight yesterday, pending approval by commanders.
The return has a limited flight clearance that includes an engine inspection regimen and restricted flight rules, Kirby said, adding that the limits will remain in place until the root cause of the engine fire is identified and corrected.
“While the investigation is not yet complete, “we haven’t seen anything that points to a systemic issue across the fleet with respect to the engine,” the admiral said.
Even with the return to flight, U.S. and British officials decided not to send Marine Corps and Royal Air Force F-35B aircraft across the Atlantic to participate in the Farnborough airshow.
“This decision was reached after a consultation with senior leaders and airworthiness authorities, despite the decision by airworthiness authorities to clear the aircraft to return to limited flight,” Kirby said.
“While we’re disappointed that we’re not going to be able to participate in the airshow,” he added, “we remain fully committed to the program itself and look forward to future opportunities to showcase its capabilities to allies and to partners.”
Under the rules of the flight resumption, the F-35s are limited to a maximum speed of Mach 0.9 and 18 degrees of angle of attack. They can go from minus 1 G to a 3 G’s, the admiral said. After three hours of flight time, each front fan section of each engine has to be inspected with a borescope. “That was a pretty significant limitation in terms of being able to fly them across the Atlantic,” he added.
The Air Force is in the final stages of authorizing the F-35A to return to flight. Coordination is ongoing between the Joint Program Office, Air Combat Command, Air Education and Training Command and Air Force Materiel Command to ensure accurate return to flight instructions are delivered to Airmen.
“This is the same process the Air Force uses after any suspension of operations,” said Col. Carl Schaefer, Air Force Joint Strike Fighter Integration Chief. “Safety remains our top priority as the F-35 resumes development and training flights.”