What's it really like?
But it's interesting, all at the same time. It's not something you want to make a career out of, unless you like seclusion, isolation, small spaces, bad odors and not having any women around.
I served 5 years on a ballistic missile sub, SSBN 633, the U.S.S. Casimir Pulaski. It was 425 feet long, and about 33 feet around. It had 16 Trident C-4 nuclear missiles. Our job was to cruise around in the Atlantic Ocean about 400 feet down, patrolling in circles to make sure no one was following us. We were the doomsday machine, so we wanted to make sure no one knew where we were.
I was on an older sub... it has since been decommissioned. It was built in the early 1960's. The newer ones are much more comfortable and spacious, but still no cake walk.
We had about 125 people on board. There was nowhere on the sub that you could pass someone walking the other way without both of you turning sideways. Our sub had 7 compartments, each with a circular water-tight door. So, every 40-50 feet you had to duck and step up at the same time to go through a small circluar opening. If you were taller than 6 feet, you'd have to do a bunch of ducking everywhere you walked. Tall people bumped their heads a bunch.
Bathroom odors weren't really that big of a problem outside the bathroom. The sub has all kinds of weird smells inside, so farts really just kind of mingled in with the other smells. Amine, diesel fuel, and other industrial smells permeated the whole submarine, making the place smell really, really bad. You don't notice it after 90 days underway... but you notice it big time first time you go down into the sub. The smell gets into your hair, skin and clothing. I took some civilian clothes with me the first time I went on patrol...without putting them in a plastic airtight bag. I had to throw them away after I got back. You cannot get the smell out completely. Not out of your clothes anyway. It's a very distinct smell. Any submariner knows what I'm talking about. Wheeeew.
The bathroom waste goes into a sanitation tank which is piped off board after pulling back into port.
The food on submarines is actually the best in the armed forces... for the first 6 weeks or so. Then all the fresh food has been eaten or gone bad. Eggs, milk, bacon, beef, etc. don't last long enough to have them the whole time you're on patrol. You'll start off eating really well, but as the patrol goes on, the food gets worse and worse. By the end all you get for breakfast is pancakes... every day.
We used to be allowed to smoke, but they don't allow that any longer. Not since the mid 1990's.
It is noisy, particularly in the engineering spaces. The hum of all the motors, generators and pumps gives a high-pitched whine that is constant. It's also rather warm back in the engineering spaces.
You deal with personality clashes with humor. We all ragged each other to hell and back. Constant ribbing. It's a bunch of guys, afterall. We used to have a book we'd pass around where we'd draw pictures and tell jokes about each other... and mainly the captain. (We just had to make sure he never found the book!)
On a ballistic missile sub, we had 2 crews.... a "blue" crew and a "gold" crew. Each crew would take turns commanding the sub. We were on roughly a 100 day rotation. They would have the sub for 100 days, then we'd take over for our 100 days. Fast attack subs never know... they might go out for a few days... or 6 months. You never know. If they go out for 6 months though, they'll do some port-hopping. On a ballistic missile sub you rarely pull into port unless you're pulling back into your home port to turn the sub over to the other crew.
I'm from the U.S.
All in all, submarine duty is lonely, smelly, long hours, not a lot of sleep, cramped, and time goes by really slowly. 90 days at sea can seem like an eternity. You get to learn a lot about the sub, and it can be interesting, but it's only interesting for a short period of time... after that, you've pretty much had your fill.
One more thing... no windows. And once you're underway and submerged, you can't really even tell you're moving unless they decide to change the angle of the ship. We used to joke that we were still tied up to the dock the whole time.
The most fun time I had while on the sub was when we did a swim call about 50 miles off the coast of Bermuda. We stopped and let everyone out on the top deck to go swimming. We stopped when the sharks started coming around, naturally. Beautiful water though.
EDIT: About the smoking. We smoked pretty much anywhere but the mess hall when I was in the Navy, back in the early 90's. Rumor was they were banning smoking the next patrol. I just assumed that they had gotten rid of smoking altogether. Sounds like they might not have. I figured that wouldn't fly too well.