"A question about nuclear subs" Topic

Not found much of use on the internet, but I'm looking for a rough percentage break down of what volume/mass of a nuclear sub is reactor/propulsion, living space, weapons, control, etc? My alternative is get one of those kids book cut away images and estimate from that.

I think if you find a few diagrams online and make some estimates, maybe averaging over a few drawings, you'll come up with numbers good enough for most purposes. Take a stab at it, then we can all argue about it, then you're employing "the wisdom of crowds"!

I don't think you will find the exact percentage, but doing a search for "nuclear submarine cutaway diagram" gives some images that would give you an idea.

It might be easier to help if you said why you were looking for the information.

Its not going to be a percentage. Its going to breakdown into an almost set volume which will be different for different subs and their function. For instance most torpedo rooms should be about the same size. Most reactors should be about the same size. Missile rooms will be determined by missile type and how many. Bridge, Crew Quarters, mess hall, etc… should be the same size.

By "same" I mean maybe different by a few feet but if you look at most cutaways they seem very similar in size and placement.

Percentages are going to be OK rather than set since there are quite a few variables in all those aspects and others that drive against a "set" volume. For example, how many reloads do you want in your weapon stowage compartment, how many missiles? how many crew and hence what degree of automation? What operational endurance and hence what volume for food and spares? Boats designed with similar philosophies are going to see roughly similar percentages devoted to each function (for my sins, submarine design is one of the things I've had more than a hand in over the years)

Twilight 2000 had 3 modules based upon nuclear subs, perhaps there are some good stats there. One sub was a Typhoon and another was a Los Angeles class. Twilight 2000 had some very detailed stuff in it.

For a fast-attack sub, roughly half the hull volume is the engineroom (maybe as low as 40%, since nobody sleeps back aft).

Missile sub like the Ohio, probably 25% of the hull volume is engineroom, ~50% is missile compartment and berthing, remainder is other operational stuff with a small torpedo room.

@Lion
Thanks that's great.

I was just looking at some old school sci-fi ship design rules and trying to work out whether they were using wet Navy analogies. I have actually been in a mocked up engineering control space for a nuclear sub – but that's it and it didn't really give any impression of what the rest of the boat might have been!

@Kropotkin
Remember seeing those – though never played them. Too busy blundering around Europe in a Marder…playing scenarios based on the Zone novels.

Let's see here…

The ballast tanks are at the extreme fore and aft, you lose about 50ft off the front and at least 100ft off the rear.

The reactor compartment doesn't actually fill the entire hull diameter, there's a 'don't linger here' path on the upper level from the missile compartment to the engineroom. Only three watertight doors in the entire boat, one from engineroom to missile compartment (starboard side, upper level). The other two are at the forward end of the missile compartment (port side second level and amidships 3rd level).

Three water tight doors? That seems rather 'minimal'.

Only 3 compartments (well, 4 counting the reactor compartment).

You see, a watertight door is a noise source, and that click as it latches goes straight out to the hull and into the water. We almost always left the forward doors open, and often left the engineroom door open when rigged for quiet.

Modern torpedoes are big enough to one-shot most subs, after all, so additional watertight compartments aren't an aid to survival.