(Updates with comments from Pentagon’s chief tester beginning in ninth paragraph.)
Feb. 13 (Bloomberg) -- Defense Secretary Leon Panetta told lawmakers he is “acutely aware” of the “many challenges” in production and testing facing Lockheed Martin Corp.’s F-35 fighter, the military’s costliest weapons program.
Panetta commented in a letter today to leaders of the Senate Armed Services Committee, who questioned his Jan. 20 decision to lift a yearlong “probation” on the most complex version of the plane, the Marine Corps’s F-35B short-takeoff and vertical-landing model.
“I made the decision to lift probation because the F-35B is now demonstrating development, test and production maturity comparable to, and not substantively different from, the other variants” of the jet, Panetta said in the letter obtained today. “I am acutely aware of the many challenges remaining. My decision will result in absolutely no reduction in the oversight and attention given to each of the variants going forward.”
Panetta’s predecessor, Robert Gates, placed the plane on a two-year probation in January 2011. The jet needed to demonstrate greater reliability in testing and show progress toward identifying solutions to unique problems with the Marine Corps model’s propulsion system, he said.
The B model is being watched as a bellwether for the $382 billion F-35 program. The Marine Corps plans to buy about 340 of the aircraft that can take off like a conventional fighter and land like a helicopter. The Defense Department’s fiscal 2013 budget, released today, proposes buying 41 B models through 2017, including six annually through 2015. Italy also plans to buy as many as 60 of the jets.
“Some additional technical issues have been identified since probation began, however these are consistent with the kind of discovery to be expected in a development program,” Panetta wrote to the Senate committee’s chairman, Democratic Senator Carl Levin of Michigan, and its top Republican, Senator John McCain of Arizona.
McCain and Levin had asked Panetta to explain what specific actions Lockheed and the Pentagon had taken before probation was lifted.
Panetta responded in his six-page letter to the lawmakers’ specific concerns. Progress was being made in identifying issues with software, lift-fan door actuators and the propulsion system’s auxiliary air inlet doors, clutch and drive shaft and bulkhead fatigue cracks, he said.
Michael Gilmore, the Pentagon’s testing chief, said his office didn’t participate in the decision to put the aircraft on probation or to lift it.
“The program has not completed the final re-designs for all of these deficiencies,” Gilmore said in response to questions from Bloomberg News.
“A significant amount of flight test and development of system maturity of the final propulsion system designs remain before the fleet will be able to use” its short-takeoff and vertical landing capability in combat situations, Gilmore said.
The B model also will face “difficulty” integrating new components into the aircraft as it’s being tested, he said.
That’s because “the designs of the new components have to assure no new, unacceptable deficiencies are created” by adding weight or changes that affect the aircraft’s structural strength or durability, according to Gilmore.
The F-35B has only a 230-pound margin between its current weight and a maximum threshold that Gilmore said “will be a significant challenge” to avoid breaching.
--Editors: Larry Liebert, Steven Komarow
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