F-35C had wing spar crack

A crack was discovered in one of its 13 wing spars of the F-35C durability testing ground article last month. The Pentagon has determined that modifications are needed on existing jets to ensure full life operation.

F-35C Lightning II of VX-23 in flight in November 2014
By U.S. Navy video by Mass Communication Specialist Eli K. Buguey [Public domain], via Wikimedia Commons

No aircraft has been grounded because of the crack and the U.S. Navy is still on course to declare Initial Operating Capability (IOC) of the C-model in August 2018.

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