Reuters is reporting that US Congressional negotiators have agreed to fund contined development of the General Electric/Rolls-Royce F136 alternate engine for the Lockheed Martin F-35 Joint Strike Fighter.
The Pentagon had sought to cancel the F136 to save money, and the $480 million in FY2008 funding will have to come from somewhere, but the preservation of a competitive engine choice is good news for the JSF programme, and for F-35 operators.
Although it looked likely, the F136′s survival can’t have been harmed by Pratt & Whitney’s recent issues with its F135 primary engine. The failure of an engine on a test stand in late August has proved a problem for Lockheed as it works to get the first F-35 back in the air after a six-month hiatus.The test-stand failure was traced to a turbine-blade cracking caused by high-cycle fatigue. Lockheed was allowed to resume ground runs in early October and hoped to avoid having to remove the engine, further delaying a return to flight. But now the JSF programme office wants a different F135 tested and installed in the aircraft before it flies again.
All new engines – and new aircraft – experience unexpected difficulties during development, so don’t read too much into this. But all F135 testing was halted while Pratt worked to uncover the root cause of this failure. As no F-35s were flyable at the time, it wasn’t too much of an issue. But on one level, that kinda validates the argument for alternative engines.