US Navy ships generally drydock on a 5 year interval, and the bottom (and usually the whole hull) get taken down to parade rest and repainted.* There*are also regular inspections and mechanical cleanings of the bottoms, sea chests, running gear, sonar dome, etc., with the ship in the water (at least yearly).* These are all part of the ship's lifecycle maintenance plan.* I'm not sure what they are using for paint now, but I'm sure with all the environmental constraints, that it is not the same as in the past.
Believe east coast aircraft carriers drydock at either Norfolk Naval Shipyard in Portsmouth, VA, or at Newport News Shipbuilding.* Not sure where they dock on the west coast.* Small boys (Cruisers, Destroyers, Frigates, Amphibs) can drydock at any number of commercial shipyards on both coasts.* When I was in command of my ship, we drydocked at Bender Shipyard (now Signal) in Mobile AL, and when I had command of*a Destroyer Squadron in Mayport FL, all my ships drydocked at Atlantic Marine on the St Johns River in Jacksonville.* Both of those are floating drydocks.* Atlantic Marine also has a marine railway that can pull a Frigate or USCG cutter out of the water.* Pretty cool...
Glenn
CAPT Glenn Zeiders, USN
M/V SYREN
Jefferson 46