F-35B delays lead to rephased flight-test schedule

Washington DC
Source:
This story is sourced from Flight International
Subscribe today »

The F-35 programme is likely to have a reshuffled flight-test schedule again as Lockheed Martin continues to struggle with the reliability of the short take-off and vertical landing variant.

It is not immediately clear if the possible "rephasing" of the flight-test schedule would result in a new overall delay for any of the three F-35 variants. Addressing a group of market analysts on 1 September, Lockheed Martin chief executive Robert Stevens says a recent push to improve the reliability of the F-35B STOVL variant has fallen short of expectations.

As a result, an ongoing technical baseline review commissioned by the F-35 joint programme office is focusing on the viability of a dramatically reduced flight-test schedule adopted earlier this year.

"I'm quite sure we're going to see a re-phasing of the STOVL flight-test programme to recognise actual performance to date," Stevens says.

lockheed martin f-35b jsf, lockheed martin
 © Lockheed Martin

The previous schedule called for Lockheed to complete more than 1,200 flight tests by all three variants in fiscal year 2010. Government officials relaxed that number significantly earlier this year, dropping the overall number to 394 flight tests this year and about 1,000 in FY2011.

But the STOVL version has failed to keep pace with the government's reduced expectations.

Stevens says that a series of reliability improvements has delivered positive results for the flight-test programme, but not enough to overcome the increasing delays.

"We're catching up but not at the rate at which he had [predicted] in the initial plan," Stevens says.

The results of the technical baseline review will be finalised by November, Stevens says.

Rephasing the flight tests will allow Lockheed to "move resources and talent in place to improve the flow of reliable parts and recover flight tests and test points", he says.

By the end of July, Lockheed's four STOVL flight-test aircraft had completed 74 out of 95 scheduled flights.

Stevens had attributed the flight-test delays to poor reliability on key components, such as thermal cooling fans, door actuators and power system switches.

The F-35B's reliability problems do not require "fundamental engineering" changes and the aircraft "has a good flying character", Stevens says.