Reagan’s pretty new, isn’t she? ‘Course, I don’t know doodly about ship maintenance. I thought they were suipposed to go a few years without major surgery, is all.
I know a considerable sum as I went through a year long carrier overhaul before. It really doesn't matter that it's a nuke. About every 5 years or three major deployments they have to have a major overhaul. This is for things like steam line repairs, galley equipment replacements, Generator overhaul/replacements, Chiller Plant repair/replacements, walk in cooler /refrigeration maintenance, Desal plants to make fresh water, and lots of other equipment. To replace anything second deck and below means the decks have to be cut open down to that level where the equipment is. That takes time and must be done in a shipyard enviroment as the ship's water tight integrity is compromised.
Also the catapults, arresting gears, and related flightdeck equipment get an extensive overhaul. It takes about a year. After every deployment of six months to the MED SEA or PG the ships require a three month shipyard maintenance. Again decks are cut open but these yard periods are not quite as intensive and the crew remains on board.