Theres been issues with virginia's, parts that were expected to last the life of the sub are having to be replaced. Because they were expected to never be replaced the spares dont exist so they taking them from in build subs
Among the biggest challenges is that the Navy assumed certain parts of the sub would last the life of the boat. However, as in-service Virginias arrived for maintenance, the Navy found it had to replace parts that weren’t supposed to need replacing. Since there aren’t spares available, maintainers have been taking the parts from the construction line, slowing down production at Electric Boat and Newport News Shipbuilding and contributing to those new boats being late, Stefany said.
“Whether it was bad design, bad assumption, whatever — it is what it is, so now we need to go do something,” he said, and the new PEO SSN will make that easier to coordinate by having a single flag officer in charge of SSN construction and sustainment.
https://www.defensenews.com/naval/20...n-maintenance/