If I was the Navy I’d have a problem outsourcing work to shipyards not used to handling classified work. It would be too easy to sabotage a sub. Also, the equipment aboard is largely classified. Heck, if the NSA can’t guarantee its classified contractors aren’t going to publish national secrets, how could a dockyard guarantee a welder won’t purposely create a few bad welds that will fail at depth?
“how could a dockyard guarantee a welder won’t purposely create a few bad welds that will fail at depth?”
Ask GE’s Electric Boat division.
They built them all.
With civilians. With clearances.
They outsourced the work to Newport News, which probably built the submarine in the first place. I’m sure they’re capable of handling the overhaul.