San Diego Source > News > F-35 Marine Model Stress-Testing Halted After Cracks Discovered
Jan. 12 (Bloomberg) -- Durability testing on the most complicated version of Lockheed Martin Corp.’s F-35 was halted last month after “multiple” cracks were discovered in the fighter jet, according to the Pentagon’s testing office.
The previously undisclosed halt in high-stress ground testing involves the F-35B, the Marine Corp’s version that must withstand short takeoffs and landings on carriers and amphibious warfare vessels, according to an annual report on the F-35 that Defense Department testing chief Michael Gilmore sent to Congress yesterday. Flight testing wasn’t affected.
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Durability testing is intended to stress an airframe, assessing its capability to achieve a projected aircraft lifetime of 8,000 “equivalent flight hours.”
Testing for the Marine short-takeoff-and-vertical landing version was progressing this year until last month’s halt “after multiple new cracks were found in a bulkhead flange” on the fuselage’s underside during an inspection after the equivalent of 7,000 hours of testing, according to the report to Congress. The cracks were confined to that area.
Testing of the F-35B model had been restarted in January 2012 after a 16-month delay caused by the discovery, analysis and repair of a previous crack in the plane’s bulkhead. All three models of the F-35 are required to go through ground testing to the equivalent of 16,000 hours of flight.
A bit unsettling news in light of the already paperthin weight margins as described by the latest pentagon rapport.