I was wondering if we could create science research submarines that are as large as military nuclear submarines. This is because I have not seen any large research submarines they all seem to be small submersibles. Additional Questions What would a large research submarine include? In what ways would it be different from a military submarine? Why don't we have any large research submarines in the world today?

  • 2
    $\begingroup$ Hello and welcome to WorldBuilding.SE! Normally it is not a good idea to have multiple questions all in one. We like one answer per thread. Maybe you could ask one question now, wait for an answer that is acceptable and get some ideas from all comments/answers and then incorporate that knowledge to make more question about specific details. Also: many people here probably don't know how large the submarines you are talking about are. Please edit your question to provide details about the size, possibly with links to sources you found. Have fun! $\endgroup$ – Sec SE - clear Monica's name Feb 22 '17 at 22:58
  • 4
    $\begingroup$ BTW: I have no idea about submarines, but if we can build a big one for the military with enough money we should easily be able to build a big one for science. Is there maybe some reason behind science-submarines being smaller than military ones? Like shorter expeditions, less cargo, less personal...? Some info what you are trying to achieve (as "science" is pretty broad) would be nice, too. $\endgroup$ – Sec SE - clear Monica's name Feb 22 '17 at 23:00
  • $\begingroup$ What are the defining differences between a military or science submarine? Because if it just comes down to the contents, then it is obviously feasible. $\endgroup$ – Kaz Feb 22 '17 at 23:17
  • $\begingroup$ @Secespitus in this articular case, question about what would be on board makes sense, because it answers "why?". $\endgroup$ – Mołot Feb 22 '17 at 23:29
  • 1
    $\begingroup$ The question to ask is what benefits would you get from a large research submarine that you wouldn't get from a small one. I can't see any, but I can see some advantages to small. You can carry a small submersible around on a mothership faster than you could sail a big submarine, you need a smaller crew (I mean support people, not researchers), you don't scare critters or otherwise disturb the marine environment as much... $\endgroup$ – jamesqf Feb 23 '17 at 1:06


We can build large submarines, military ones are sure proof. And with unlimited money you can pretty much do what you want if you are not disturbing money flow too much. So why not?

... but you are asking wrong question

Look at CERN. Big, expensive. But each and every part was build for purpose. If I'm not mistaken, its cost was much larger than a few large submarines, so even with limited money expensive scientific projects are possible.

Thus, the question shouldn't be if, but why would we do that. Basically, inside your world flow of thought would be opposite:

  1. What and why we need to examine?
  2. What instruments will be needed?
  3. Where can we fit it?

My money goes for neutrino detectors

These are already expensive, so the additional submarine price won't be too much, especially for someone with infinite money. Are fairly large, this might justify big submarines. Benefit from good insulation from outside world, and a lot of water can be quite decent.

Of course, you can look for any other big detector. Scientists would like to have mobile versions of them, if you can make them to the same quality, sensitivity etc. Then, in your world create phenomena that would justify putting them on submarines and taking measurements deep in the ocean. And that's it.

  • 1
    $\begingroup$ Note: when you will decide what phenomena and / or detectors you want, you may ask another question, this time specifically about building such submarines in a way that makes sense in your world. For now, such speculations would be too broad IMO. $\endgroup$ – Mołot Feb 22 '17 at 23:36
  • $\begingroup$ Neutrino detectors won't work. Cherenkov detectors, those which use large masses of water, rely on medium being transparent in optic spectrum, and isolated from sunlight. I doubt seawater is pure enough to have required transparency. As for other reasons, maybe for some reason there's a need to spend long time below ice shelf? Though I have a hard time coming up with reason why it couldn't be handled either remotely or by small sub returning repeatedly or combination of both. $\endgroup$ – M i ech Feb 23 '17 at 5:10
  • $\begingroup$ @Miech seawater wouldn't be there in place of pure water, but in place of rocks around. But that was just an example of what I wanted to be a generic answer. $\endgroup$ – Mołot Feb 23 '17 at 6:12
  • 1
    $\begingroup$ I see. Super Kamiokande is a cylinder ~33m by ~36m, Typhoon class sub (supposedly the largest one) is roughly a cylinder 12m by 23m by 175m. Yeah, you could probably build something like that. I thought you were suggesting to place detector on the outer hull, or dangle them on strings IceCube-style to use external volume. $\endgroup$ – M i ech Feb 23 '17 at 15:58
  • $\begingroup$ @Miech yes. Something in these lines, probably. But that's a matter for a follow up question, and if it'll happen I'll be glad to upvote your answer :) $\endgroup$ – Mołot Feb 23 '17 at 16:26

First a quick bio. I managed a research vessel program for one of the world's leading marine research institutions for a number of years and have designed research vessels.

The answer is surprisingly proasiac. Not enough research bang for bucks. A military submarine has a max operational depth of ~ 500 m (Sea Wolf class, and yes classified but - engineering). While the 0-500 m part of the water column remains an area of active interest to science that only takes us to about twice the depth of the average continental shelf (~200 m). Science can work that depth range from surface vessels with a variety of existing kit that can provide hi res video and sonar down to 1mm accuracy in real time in combination with high precision gps (which a submarine at depth cannot do).

However a lot of the current interest is off-the-shelf in depths of 7000 m plus. The real engineering challenge lies in the 7000 to 12000 m range. Deploying from a sub at 500 m brings huge engineering challenges (remember the internal pressure is 1 atm) and in % terms does not bring much advantage.

@Sean Boddy is right on the money. The data gathered by military craft is hugely valuable but

  • if issued contemporaneously it will typically not be time or position tagged (for obvious security reasons)

  • If issued with time / position tags it is usually old data and so very valuable for completing the record but made on now obsolete sensor platforms, the specifications of which may still be classified.

Sean is also right when he states that if you throw a deep ocean sensing problem at scientists and engineers they will typically come up with a device that is not a submarine.

There will always be a role for the Ballards and the Camerons and the mark one eyeball at depth and I for one would go on one of their dives in a hot second. However the capability of surface deployable modern deepwater instrumentation is such that it just is not necessary to lock up a bunch of leading scientists at depth for weeks on end to gather high quality data.

The other issue often overlooked is that building cost becomes trivial in comparison to operational cost for marine platforms. The Seawolf class have a compliment of ~150 this is at least 3 times the compliment of a research vessel of comparable size (including scientists). That's three times the staff budget. I have no idea what the annual reactor costs are (Sean probably does but understandably cannot say) but I am willing to bet a body part it is considerably more than the ~8 m it costs to fuel a modern, efficient diesel / electric RV. And then we get to maintenance. Very few COTS components on a nuclear sub. I could fo on. I used to have nightmares about this stuff.

If offered the 2 billion I'd propose a fleet of multi-capable surface vessels (15-20) sharing a pool of cutting edge, upgradeable sensors rather than a single craft, no matter how depth capable.

  • $\begingroup$ ... and a btw a military submarie is not a big vessel. Again Seawolf class 10000 t. This is related to pressure vessel engineering. Cost goes up at ~ 4th power of volume. I've worked surface vessels that could load 12 of these and still have spare capacity. There are supertankers out there with an uplift capacity of 500,000 t. $\endgroup$ – pHred Feb 23 '17 at 12:08
  • $\begingroup$ Actually your last point is your most important, and the most spot-on. Being a lowly electrician at the time, I did read that several admiral flavored submarine officers at the war college were calling for distributed, remote, mobile emitter and sensor suites for active sonar, supposing that it became possible. Active sonar gives away your position, and distributed emitters are easier to upgrade, cheaper, and less likely to give a clear fix on your position. It's the same rationale, applied tactically to shooting things and not getting shot back. $\endgroup$ – Sean Boddy Feb 23 '17 at 17:30

First, a brief bio - I spent 8 years in the US Navy as a nuclear trained Electrician's Mate. The training itself is a bit like going to college for all the painful, drawn out bits of vocational school, operator school, and electrical engineering all at once, crammed into a year and a half, without the social sciences and humanities requirements of an ordinary college. The end result is a group of people uniquely qualified to both operate submersible nuclear reactors, and to convince people to feel good about having these things in their back yards (seriously, I was safer from radiation on that submarine than I am sitting in front of my computer at home right now.) But this isn't about me, so on with the science.

Setting aside for a moment the real-world issue of cost-effectiveness, I want to take a moment to expand the way you think about this issue. With seventy-something active submarines in the US fleet alone, what makes you think we aren't using those for research right now? Our readiness plans as a nation are going to include submarines for the foreseeable future, and those submarines frequently will go on exercises to maintain their abilities - if you look at it as a single machine, it is one of the most complicated ones in the world. When the crew has an average age of 22 or so, and that crew is constantly gaining and losing people due to personnel transfers, they need a lot of practice.

Logically, we're going to be out there anyway. We maintain running logs of a number of environmental factors, some of which should be obvious. (I would comment more on this, but I have a legal obligation to not discuss onboard equipment.) If we can run an experiment without an unauthorized refit, or if NOAA or NASA wants us to make an observation for them in our area, there are quick and easy ways they can ask us, one of which is almost exactly like a phone call.

In a more generalized, world-building point of view, there is a much better answer to this question - by the time you have done enough work and research to build an enormous research submarine, there is virtually nothing left for an enormous research submarine to teach you. Somewhere along the way, you'll have to build test platforms, and when you do you'll give it tests and experiments it can hopefully run for you. If it fails, you'll redesign it, and - here's the important bit - making it bigger will always work against you. Force per unit area over a large area makes a large force, and when that force is trying to crush your new toy into a ball, it is reasonable to design away from that. Case in point, google American submarine NR-1. It was itty-bitty, operated for over three decades, retired 9 years ago, and anybody who actually knows how deep it can go isn't allowed to talk about it. (No, I do not know how deep it can go.) But it only existed because we basically wanted to know if we could do it, and it gave us some answers about what's down there.

If you actually come up with an experiment that you think needs a very large, very deep submarine to manage it, ask a scientist and an engineer to take turns looking at it, and they'll probably be able to find an answer to your question that is either not very large, not a submarine, or not either thing at all.


The answer is COST. Military based subs get the ability to be loaded with size and gadgets because they cost approximately 2 billion dollars++ per sub. Research teams are granted millions... if they are lucky. That millions has to go towards the crew and other needs. The government can afford 2 billion per sub (well maybe not as we are constantly in debt but you know what I mean). With your first question of there being no limitations on money, A research submarine could be easily tricked out with as much gadgets, tech, and size as a military based one. The size ultimately is due to cost.

As far as gadgets and what not goes, that depends entirely on the type of research vessel it is... a vessel looking at animal life may have a lot more cameras. If they are studying ocean floor volcanic activity, they may have seismographs as a main bulk of their tools. Again can't really speculate what they would have because something like that would be highly specialized to the type of research it is conducting.

They would be different because military submarines are built for combat. Research submarines would not. Targeting systems, torpedo and missile systems, and added reinforcement/protective features would be removed and replaced with things that enable a science vessel to do their job better.

Your last question goes back to the initial question asked about cost. We don't see them because Robert Ballard doesn't have 2 billion dollars to invest in a large submarine and run the risk of it being destroyed and having to spend another 2 billion to replace it. It is much easier to replace and find fundings for a mini sub of 1 million dollars.


Sure. In fact, the US Navy built the nuclear submarine NR-1 in the early 1970's. It had an unclassified depth rating of 3000 ft. It carried a crew of 10 plus 2 scientists on missions of up to 28 days. NR-1 was regularly used by researchers, which made important contributions to deep-ocean science. See for example: MacDonald, I. R., I. Reilly, J.F., Guinasso, Jr., N.L., J. M. Brooks, R. S. Carney, W. A. Bryant and T. J. Bright (1990). "Chemosynthetic mussels at a brine-filled pockmark in the northern Gulf of Mexico." Science 248: 1096-1099. Submarine NR-1 was decommissioned in the early 2000's mostly because its reactor vessel needed replacement.

The strategic missile nuclear fleet was also used for important science, particularly under the Arctic sea ice. The mass of sea ice has declined alarmingly due to climate change and some of the best data on this came from sonar observations looking up through the ice.

There are many conceivable science missions for a deep-diving nuke submarine, but that's another question. Doubtful thought that one could be made as large as the big boomers--which were huge. Increasingly ROVs, AUVs, drifters and gliders are being used because they are cost-effective and less challenging to human safety. Submarine ALVIN remains in service and just had its titanium sphere replaced with a slightly larger version that will eventually extend its range to 6000m! I've heard all the arguments about robotics, but there is something intangibly valuable about being able to look out the window and see the ocean bottom with binocular vision. That said, it's also nice to see it on a video screen and be able to go to the bathroom when you need to. (That wasn't a problem on NR-1, but it did get pretty smelly after a week or so.)


Bear in mind that your military sub is built for one purpose and one purpose only. Whether it is to launch ballistic missiles or sink battleships, that is all it will ever be expected to do during its working lifetime.

Your research submarine is the same. It's specialised to do one thing, and one thing alone, very well. This takes as much space as it takes, which apparently isn't very much, compared to a military submarine. If you want to make it a Jack-of-all-trades, you'll have a behemoth that does a lot, but none of it very well, and is disproportionately high maintenance, like the F35 (allegedly).

So, could we? Yes, definitely.
Would we? Depends on whether it's better than making multiple small submersibles, in terms of both price and performance.

  • $\begingroup$ Modern submarines are multimode. I mean, yes, overall, it is a military unit designed for that purpose, but that purpose includes anti-sub, anti-surface, projection of power ashore, surveillance, special unit deployment and retrieval, drug interdiction. And the Virginia class subs are outright modular. That's just FYI, though, your point is still fair and valid. $\endgroup$ – Sean Boddy Feb 23 '17 at 6:34
  • $\begingroup$ @SeanBoddy: And till the end of it's lifetime ~20 years, it will do exactly those jobs, in exactly that manner as on the day it was commissioned. A research submarine would be expected to upgrade its equipment and adapt its procedures around those regularly. A multifunctional research submarine would have to balance changing systems and equipment within the constraints of life support in the second most hostile environment known to man. Really not worth it. Just think of the amount of work involved in making even minor changes to the ISS. $\endgroup$ – nzaman Feb 23 '17 at 8:43

The size that vessel needs to be is really a function of the payload it needs to carry. A ballistic missile submarine is large because it needs to carry several large ballistic missiles, plus the crew, other systems and enough supplies to remain at sea for several months at a time.

Most research submarines are small because they don't have to carry a large payload and there's no point in wasting the money on a larger vessel. If your submarine had something large that it needed to carry then it would have to be bigger.


I don't see why not but I am not sure why it would be the best idea. A great deal of the ocean's floor is more or less deserted. I would build a stationary underwater facility in a particularly interesting spot and a couple of underwater "freighters" to ferry supplies to it and to remove waste items. It would do two things. First it would help us study our own planet and secondly it would be a place to train crews for the long journey to other planets like Mars. We would learn a lot about making the trip but have the people a lot closer at hand in case we run into serious issues for a long trip like that that we have not yet considered.

  • $\begingroup$ not sure that an underwater base would be too ideal. They wouldn't be able to put on a swim suit or a scuba suit and just walk out. The pressure would be too great. That would make them stuck within the facility and would still need to invest in subs to take them about the area. $\endgroup$ – ggiaquin16 Feb 22 '17 at 23:38
  • $\begingroup$ Base, habitat whatever. Did not say they had to be deep. You brought up costs above and you can double for the biggest subs, 4 billion. You could put down multiple habitats in "interesting areas" for the cost of one large nuclear powered submarine. His last question "Why don't we have any large research submarines in the world today?" The answer to that is it is not cost effective. Scientists will never get billions of dollars to play with. By the way the military funded Ballard's mini-sub but not out of the goodness of their heart either, had to go find a couple of missing subs for them. $\endgroup$ – Anita Heuss Feb 23 '17 at 2:33

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.