Clearly we should be turning aircraft carriers into post-apocalyptic bases with hidden androids.... http://fallout.wikia.com/wiki/Rivet_City
Only nuclear carrier, yeah. There've been a bunch of nuclear subs and cruisers retired . . . not that we had that many nuclear powered cruisers.
As people have said, not all are. All of the currently commissioned carriers are indeed nuclear powered. The key to your question is that the two old carriers under consideration in this thread are NOT nuclear powered.
Nine nuclear powered cruisers (though some were originally designated destroyers and frigates IIRC). Long Beach (Enterprise's traditional escort), Bainbridge, Truxton, two California class cruisers and four Virginia class cruisers.
Yeah, that's right! Fucking hippie dippy hipster fruitcakeland Portland has a submarine. And, used to have a Pre-Dreadnought battleship. PORTLAND. Let that sink in for a moment.
I just drove past a bunch of flatcars with submarine hull segments on them at Puget Sound Naval Shipyard. I wish they'd label them, I'd love to know what boat that used to be.
Well of course. Originally the AEGIS equipped cruisers were supposed to be nuclear powered, but IIRC it costs more than 50% more in initial construction costs to equip a surface ship with nuclear reactors. So having conventional fired AEGIS equipped ships was ultimately a cost cutting move.
I sometimes wonder if that's true over the lifetime of the ship, given the costs of Navy distillate fuel or JP-5 for the turbine-powered ships versus the "fuel it every ten years and call it good" nature of nukes.
I've heard that nuclear power does make a lot more sense. Over the long run. But try telling a Congressional committee that "this will save money over the next 3o years Also note it isn't just the ship fuel you have to pay for but for the fleet oilers, and their crews, and their fuel to transport the warships fuel overseas. I think there are a lot of merits to powering not only your carriers and submarines but ALL your surface warships with nuclear reactors AND having nuclear powered resupply vessels to radically reduce your fleets logistical train. It won't matter that much in peacetime but if another real war is ever fought, that might be an issue.
There's some interest in powering naval vessels with liquid fluoride thorium reactors, which have a much higher power density, higher efficiency (because of the larger delta-T), and vastly greater inherent safety. Since gases like xenon constantly boil out of the liquid, they don't build up to poison the reaction (suck up the neutrons) during combat maneuvering.
Current U235 reactors don't have that problem with xenon either. Xenon doesn't build up in a reactor at power. Xenon is only a problem immediately after shutting down, and only on cores that are close to end of life.
Yes, but your enrichment levels are extremely high so the reaction can stay fertile after a shutdown. The Chinese are going full bore on liquid fluoride reactors, and one concern is that they aim to use them to create a nuclear blue-water navy. One of the thoughts on thorium reactors is that they might make sense even on destroyers. Here's an older study investigating their possible use on a warship of about 8,000 tons.
The high cost of nuclear ships doesn't end when the last seam is welded. Maintenance on nuclear ships is very expensive. The requirement is there, and will be met, no matter the cost. On non-nuclear ships "good enough" is usually accepted for a repair. Also most repair jobs are weighed with a cost/benefit analysis and work can and is often deferred until later. (On a completely unrelated note, I spent Thursday and Friday riding an Aegis cruiser on sea trials.)
I don't think Portland did -- I haven't heard anything about any battleship at the bottom of the Willamette
One of the arguments in favor of liquid thorium is that they run at low pressure, virtually atmospheric pressure, so you don't have the issues with high pressure equipment. In fact, one of the safety systems is that the reactor is only plugged by some solidified fuel, kept solid by blowing cold air over it. Leaking is a design feature! The presumed lower level of required maintenance and servicing is why they could consider them a viable option for a destroyer. Heck, they even ran one in a bomber. Unfortunately the Chinese are crawling the Internet reading those same reports, and if they get workable naval reactors in ten or fifteen years, the US Navy might want their own counter. They certainly have the expertise to race ahead anytime they feel like it. ETA: On an unrelated note, the other day I noticed that the Ticonderogas are 40 feet longer than the HMS Dreadnought, though only half the displacement.
USS Oregon, BB 3. Scrapped in Japan in 1956 after being taken back by the government in 1941, and used as an explosives barge at Guam during the war.
A friend's son-in-law is a nuke tech on a boomer. They refueled his sub recently, which involved dry dock, and cutting a whole section out of the middle, then replacing and rewelding it afterward. The first dive after reassembly must have been... interesting. He's now been assigned to a submarine training facility where, he says, they have a retired and defueled boomer set up to train in. On land.
They do hull cuts on subs pretty much any time they drydock one. There are drawings that show where all of the standard hull cuts go. The QA and welding process is pretty unreal when reinstalling those cuts. They have to make them to install and remove components too big for the normal access routes and for "service" lines that would clog the normal access's. And yeah, the "deep dive" after an overhaul is fun. It's very controlled though, you don't just drop to test depth, it's slow and incremental.