Pentagon acquisition czar Frank Kendall and F-35 boss Air Force Lt. Gen. Christopher Bogdan Monday cited an “extensive rub” of a third stage fan blade as a key factor in a F-35 runway fire that lead to the Air Force’s initial grounding June 23, according to F135 engine manufacturer Pratt & Whitney.
Pratt & Whitney spokesman Matthew Bates said Monday Bogdan and Kendall also confirmed that the company has inspected all other engines in the fleet, but only the incident engine on the AF-27 jet exhibited this condition. Bates said Pratt & Whitney has provided data to the airworthiness authorities to help them make a decision about returning to flight operations, including at the Farnborough Air Show in the United Kingdom.
The Defense Department’s grounding of its F-35s continued Monday, with the Air Force’s no-fly streak hitting 21 days. DoD grounded the entire fleet July 3. DoD didn’t fly its F-35B at the Royal International Air Tattoo, also in the United Kingdom last weekend, which the Pentagon was keen on doing. DoD still hopes to fly the F-35B at Farnborough this week.
The F-35 is developed by Lockheed Martin [LMT] with subcontractors BAE Systems and Northrop Grumman [NOC]. Pratt & Whitney, provider of the F135 engine, is a division of United Technologies Corp. [UTX].