Because of supply chain issues, and because the assembly line is being constantly raided to keep the test fleet flying, Lockheed Martin is having to partially dissemble the wing on the F-35 to install components out of sequence:

Lockheed Martin has pushed back the resolution of a manufacturing problem plaguing F-35 Joint Strike Fighter final assembly schedules, but key suppliers are making progress building components as the programme prepares for the next leap in production orders.

In October 2009 government audit reports showed that Lockheed expected to eliminate the “wing-at-mate overlap” problem for the F-35’s four-piece wing with final assembly of BF-13, the thirteenth short take-off and vertical landing (STOVL) in production.

The overlap means that key parts are delivered after the wing has entered final assembly, requiring workers to partially disassemble the structure.

The Defense Contracts Management Agency (DCMA) identified the resulting delays and inefficiency in the wing manufacturing process as one of the key drivers for production delays ranging from four to six months during the first two years of low-rate initial production (LRIP).

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