Fatigue cracks raise questions about key decision in F-35 redesign
Questions raised over 2004 weight-saving decision to switch key F-35 structures from titanium to new aluminium alloy.
Lockheed Martin has discovered fatigue cracks on an aluminium bulkhead inside a ground test aircraft for the short take-off and landing F-35B variant after 1,500h of durability testing.
The cracks have had no immediate impact on the pace of the flight-test programme. While the engineers are performing a root cause analysis on the BH-1 durability test aircraft, Lockheed has inspected and cleared the flight test fleet and the ground test aircraft for the conventional take-off and landing F-35A variant.
