Lockheed Martin continues to struggle with some parts reliability issues affecting the Harrier replacement so short-takeoff-and-vertical-landing (Stovl) F-35 testing will force slippage in the 2012 in-service date for the U.S. Marine Corps.
Tom Burbage, Lockheed Martin executive vice president for F-35 program integration, states that 251 Stovl flights are expected by the end of this year. And at the end of August, 122 were executed of 153 that should have been conducted by that time. “Where we are short is in some specific testing, mostly in Stovl vertical landing unique test points,” said Burbage.
During a teleconference this month with investors, Lockheed Martin CEO Robert Stevens to acknowledge a potential “re-phasing” for the Stovl flight-test plan. Acknowledging the restructuring to the program announced this year, Stevens adds that “the early corrective actions . . . are showing some beneficial outcomes [but] my sense is that it is not going to be enough.” The multinational Joint Strike Fighter will eventually comprise the lion’s share of the company’s profits.
The Marine Corps, however, stands by its plans to declare initial operational capability (IOC) with a Block II F-35 in 2012. The U.S. Air Force and Navy are expecting to declare their aircraft operational in 2016.
However, further delays in Stovl testing could have a dangerous ripple effect on the program. There is little margin to ensure that enough of the flight-testing envelope and software work will be ready to allow pilots to begin training in time for a 2012 IOC. Officials at the training center at Eglin Air Force Base, Florida, say they expect their first Block II aircraft to arrive in spring 2012.
Much of this ongoing delay is a result of parts reliability problems for BF-01, the only Stovl test aircraft instrumented to conduct vertical landing trials. BF-01 is needed to clear the envelope for vertical landing, after which other Stovl aircraft can contribute to more flight testing. Five vertical landings were executed in August. Ten have been done since the first one in March. Also, last month 26 Stovl flights were conducted, the most in any month to date, Burbage says.
About 80% of the parts on the aircraft have completed qualification requirements. Of those, 100% passed for safety-of-flight; half were deemed suitable for the life of the aircraft. The remainder must be redesigned.
Burbage says the target-sortie-generation rate for each test aircraft is 13 flights per month. Last month, each aircraft averaged six.
While each parts supplier is responsible for designing parts to withstand the stresses of vertical flight for the life of the aircraft, it is the prime contractor’s responsibility to ensure that the aircraft as a whole meets its requirements. There are “some parts that just fail when you get them on the aircraft until you understand the root cause,” Burbage says, noting that experts are still characterizing the thermal and acoustic environment for these specific items during vertical landings.
Meanwhile, government officials are conducting a thorough independent technical baseline review for the entire program, which includes the conventional-takeoff-and-landing and carrier variant aircraft. This is due to the Pentagon’s Defense Acquisition Board in November.
Burbage says it is likely to include alternate paths for the program depending upon varying levels of funding. Government officials are also building the first cost estimate for the aircraft, including the operating price.
Of 394 flights planned for the three variants for the year, 233 had been flown by the end of August. Burbage says 2,361 test points were complete by that time; a total of 3,772 are expected by the end of the year.
As a result of the restructuring earlier this year, Lockheed Martin is required to stand up an additional facility for testing software to ensure this portion of the F-35 program stays on schedule. Burbage says the equipment for this laboratory will be delivered in mid 2011 and be ready to conduct testing by fourth-quarter 2011.