FT. WORTH, Texas — The U.S. Navy has strongly endorsed a single engine for the Lockheed Martin F-35 Joint Strike Fighter, citing lack of space on its aircraft carriers to support an alternate powerplant.

“I’m in the one engine camp,” said Chief of Naval Operations Adm. Gary Roughead, speaking July 28 at the rollout of the first Pratt & Whitney F135-powered F-35C carrier variant here. “On a carrier, space matters.”

The last of three JSF variants to be designed, the Navy F-35C has a number of significant differences from the conventional takeoff and landing F-35A and short takeoff and landing F-35B, including a larger wing and tail to minimize approach speed, beefed-up landing gear, arrestor hook and wing fold.

The first F-35C, aircraft CF-1, has been rolled off the final-assembly line and transferred to flight-test. An extensive first-of-type ground test campaign is planned, with the aircraft not scheduled to make its first flight until late December.

Initial operational capability for the F-35C is scheduled for fiscal 2015. The Navy plans to buy 680 F-35s, but the mix between Cs and STOVL Bs for the U.S. Marine Corps will be determined by the Quadrennial Defense Review now under way, Roughead says. “The mix of Bs and Cs is part of the ongoing discussion.”

While the fleet mix may still be in flux, Roughead says “the aircraft must come in on time.” Even assuming F-35C deliveries begin on schedule, the Navy is looking at extending the life of about half of its Boeing F/A-18A-D fleet to minimize an expected fighter shortfall.

Although the first flights of test aircraft are running behind schedule, JSF program executive officer Brig. Gen. David Heinz remains confident that development can be completed on schedule. “If we can achieve 108-120 sorties a month we can complete in October 2013,” he says.

Photo: Lockheed Martin