Pentagon belief in Joint Strike Fighter program cost estimates could be wearing thin, as delays to flight testing keep the program from proving whether it can break the mold of previous fighter development efforts and stay on budget.

The Defense Dept.'s independent Joint Estimating Team (JET) has been told to update its projections for the F-35 program, and is expected to again conclude it will take longer and cost more to complete development than the joint program office (JPO) believes.

This is raising concerns that the Pentagon will eschew the JPO estimate and budget for development at the JET's higher figure, forcing a major jump in projected program cost and potentially resulting in cuts to aircraft procurement numbers.

Lockheed Martin briefed JET officials on progress with JSF development on July 29 in Fort Worth, the day after it officially rolled out the first F-35C carrier variant for the U.S. Navy, the third and final version of the multi-service, multi-national fighter. The F-35C's first flight has slipped into January next year.

The previous JET report estimated, based on legacy programs, that development would cost $5 billion more and take two years longer to complete than projected by the JPO in 2008. The estimators cited engineering destaffing, manufacturing span times, software development and flight-test productivity as drivers of expected cost and schedule growth.

Because of delays in flying test aircraft, JSF program executive officer Brig. Gen. David Heinz does not expect the updated assessment to change the JET estimate by much. "The JET has been tasked with updating its assessment in September," he says. "Without significant flight testing I do not expect a major revision."

Program officials hope to convince the independent estimators that destaffing, manufacturing and software are on track to deliver the JPO's lower projections. "We do not believe they are right," says Dan Crowley, Lockheed Martin F-35 program general manager. But lack of flight testing means a major part of the JET assumptions cannot yet be challenged. "It's too early to prove them wrong," he says.

While it had been budgeting for F-35 development at the lower cost estimated by the JPO, for Fiscal 2010 the Defense Dept. opted for the JET's higher estimate and added $480 million to the budget request to cover projected cost growth in flight test. This raises the specter of a major jump in program cost if the Pentagon abandons the JPO estimate and embraces the JET projections.

The JPO, meanwhile, has increased its estimate of total program costs because of higher than expected prices for Pratt & Whitney F135 engines. Heinz says the company is not achieving the projected learning curve on producing the engines because of tolerance and yield issues with manufacturing parts. The estimated average cost of the engine has increased 24% to $8.3 million from $6.7 million.

The Senate stripped out $439 million in funding added to the Fiscal 2010 budget to continue development of the General Electric/Rolls-Royce F-136 alternate engine, but the House voted to add $560 million so the issue remains alive. Publicly Heinz supports the Pentagon's decision to cancel the second engine, but he is pressuring Pratt and its suppliers to cut costs.

Photo: Lockheed Martin