Inspections are to be carried out on faulty fuel tubes.
An official report questioned earlier this year whether the f-35 was ready for combat after dozens of faults were found.
The F-35 is the largest and most expensive weapons programme of its type in the world.
The programme is expected to last several decades and global sales are projected to be 3,000.
The US government's accountability office estimates all costs associated with the project will amount to one trillion dollars.