Marine Corps F-35B Flights Suspended After a Part Fails

The Pentagon suspended flights of the F-35B, the Marine Corps model of its Joint Strike Fighter, after the failure of a propulsion-system part caused a pilot to abort a takeoff.

“We are assessing potential causes and evaluating actions to return” the Marine Corps version to flight, Pentagon spokesman Joe DellaVedova said yesterday in an e-mail.

The Marine Corps model, designed for short takeoffs and landings on carriers and amphibious-warfare vessels, is the most complex of three models being built in the Pentagon’s costliest program.

The failure was in the jet’s propulsion system, made by the Pratt & Whitney unit of Hartford, Connecticut-based United Technologies Corp. (UTX) The incident occurred before takeoff on Jan. 16 at Eglin Air Force Base in Florida.

“The pilot aborted takeoff without incident and cleared the active runway,” DellaVedova said.

Development of the F-35 has been marked by delays and cost increases. The Pentagon’s $395.7 billion estimate for the total cost of development and production of 2,443 fighters is a 70 percent increase since the initial contract with Bethesda, Maryland-based Lockheed Martin Corp. (LMT) was signed in 2001.

The incident involved a propulsion fueldraulic line. The fueldraulic system saves weight by using jet fuel instead of the customary hydraulic fluid to lubricate mechanical parts.

Detached Line

“An initial inspection discovered a detached fueldraulic line in the aft portion of the engine compartment,” Matthew Bates, a spokesman for Pratt and Whitney Military Aircraft, said in an e-mailed statement.

“A team of Pratt & Whitney and Rolls-Royce engineers is investigating the cause,” Bates said. London-based Rolls-Royce Holdings Plc (RR/) makes the components of the propulsion system that enable the aircraft to perform short takeoff and vertical landing operations.

DellaVedova said, “it is the first time we’ve experienced an event with the propulsion fueldraulic line.” The affected component isn’t used on the Navy or Air Force versions of the F-35, he said.

To contact the reporter on this story: Tony Capaccio in Washington at acapaccio@bloomberg.net

To contact the editor responsible for this story: John Walcott at jwalcott9@bloomberg.net