The Pentagon has suspended flights for its entire fleet of F-35 Joint Strike Fighters following the discovery of a crack on an engine blade during a routine inspection.
The Pentagon’s F-35 program office said Friday a crack was found on a low pressure turbine blade on an F-135 engine built by Pratt & Whitney, a division of United Technologies [UTX], during a Feb. 19 inspection. It marks the second grounding related to the program since last month, when the Marine Corps variants were suspended because of a problem with fueldraulic line.
The crack was in an engine powering an Air Force conventional takeoff and landing (CTOL) F-35A variant used for testing at Edwards Air Force Base in California, but the suspension also affects the Marine Corps F-35B and Navy’s F-35C variants, Cmdr. Kyra Hawn, a spokeswoman for the program office, said in a statement.
“It is too early to know the fleet-wide impact of this finding, however as a precautionary measure, all F-35 flight operations have been suspended until the investigation is complete and the cause of the blade crack is fully understood,” Hawn said in a statement.
The Pentagon is currently operating 51 early versions of the stealth fighters. Seventeen of them are for testing and development, Hawn said. The Pentagon plans to buy up to 2,443 across the three services in the decades ahead.
The suspect blade is being shipped to Pratt & Whitney’s engine facility in Middletown, Conn., for a “more thorough evaluation and root cause analysis,” Hawn said. The Pentagon is also working closely with prime contractor Lockheed Martin [LMT] “to ensure the integrity of the engine, and to return the fleet safely to flight as soon as possible,“ she said.
The Marine Corps F-35B was cleared to resume flying just nine days ago following the mid-January grounding (Defense Daily, Feb 14). The problem with the fueldraulic line, which is in the vectoring propulsion system specific to the short-takeoff and vertical-landing version flown by the Marines, was caused by poor crimping. The faulty ones were replaced.
The fueldraulic lines are supplied by Stratoflex, a unit of Parker Hannifin [PH].
The recent groundings are the latest setbacks for the largest acquisition program in Pentagon history. Plagued by developmental and other problems, the program’s procurement cost has ballooned to $400 billion with a total lifetime cost that includes operations and maintenance of $1 trillion.