"this is useful information if you ever want to get involved in an argument on the internet or something important like that". Pure gold

"You put the water outside and the people inside". How to prove you're an engineer in 10 seconds.

Thanks for making these videos publicly accessible and free when the quality therein could easily be of commercial value since you are in my opinion the "go-to" OSINT analyst for anything naval.

When an HI sutton video drops I get excited

I was a US Submariner and the 637 class I was on, had double hull as you described. The beams were inside the pressure hull. The outer hull contained the ballast tanks, air banks, waste oil tank. the outer hull experienced sea pressure and was normally flooded while underway. I don't know about the other classes, but was under the impression the construction was similar. The little about Soviet hulls that I was aware of, is they had double hull for some classes, consisted of the two parallel pressure hulls connected by a common air lock. The double hulls were enclosed in an outter hull that held the ballast tanks similar to the single hull US 637 class. Cheers!

A very fair treatment of a controversial subject. In my past job I reviewed and helped write submarine Vulnerability Assessment Reports (VARs). One thing often overlooked with single hull designs is vulnerability due to sabotage such as a swimmer in port. It takes a surprisingly small amount of HBX explosive in contact with a pressure hull to breach 1.5 inches of HY 80 steel. The emphasis in VARs was always blue water ship on ship encounters.

When qualifying on submarines and learning the intricacies of system interactions, it was useful to consider the occupied spaces as "the people tank".

I would love to see a video where you talk about the recent advancements and innovations in submarine technology that we know off or can reasonably speculate about. Like the stealthy German U-boat 212CD. Columbia and SSN-X. Dreadnought and SNLE-3G.

I love your videos. The amount of information we have access to today is incredible.

Color me enlightened! 🙂 I have always associated 'double hull' with the ballast tanks down the side of the vessel (i.e., the old WWII-style subs), and single hull with the tanks fore and aft. I have also seen it stated that double hulls gave some standoff protection from torpedo hits. Thanks for clarifying such a seemingly self-evident topic!

I have been waiting for this video for ages and thank you for this amazing video.

Best submarine channel on KZfaq, thanks

Clicked on the video because the submarine to the right looked like the Kosatka. Ended up learning alot.

Regarding "Reserve Buoyancy", it's true that double-hull designs have a reserve displacement greater than single-hull units. However, when attempting to recover to the surface, double-hull units are required to drag the weight of all of the seawater filling their free-flood areas with them in their attempt to reach the surface. Single-hull units, in contrast, need only to dewater the flooded areas of the pressure hull while attempting to reach the surface. Something western submarine crews regularly practice.

Love all your analysis on these boats. It's always a good day when one of your videos pop! Thanks H.I.

Thank you so much for releasing another video so soon after your last! I love your content and expertise!

Since I am sure someone out there has contemplated a TRIPLE-hulled sub, I have seized the innovation tiger by the horns and I am now researching the HALF-hulled sub.

The best part is this knowledge is applicable to so many things: cashews, fortune cookies, easter eggs, etc. Pure gold!

Another great video as always! Thanks!

Thanks for the fine presentation!

Mr. Sutton the UTube algo brought your channel to my attention. I am enjoying the Level of Knowledge at display on your videos. What an ABSOLUTE JEWEL of a channel you have here. I rewatch your videos for deeper understanding! Pure unadultered quality content here!

"I'm not a naval architect" says the guy who can draw submarine cutaway drawings in MS Paint. Don't sell yourself short, Mr. Sutton 😄

Great new stream of videos :) thanks!

Great video. It debunks so many myths quickly and in a lay person's language!

2 videos in a week?! ❤

Another great video.

Great as always. I must watch it again. Very informative.

Your artwork is amazing! A video where you talk about how you render out your drawings would be interesting, I think.

fantastic, thanks!

What are the chances that I was just thinking about the topic and he uploaded 😅

The UK is now also tecnicaly in the double hull category, As the new Dreadnought class SSBN's being built has an outer hull for stealth purposes.. 🤔

Love it, more content, you and sub brief second to none 👍

HI we love your highly detailed very informative videos. Fascinating. Thank you so much

H.I. Informative as always sir; thank you!

4:37 am for me, good morning dudes.

Nice. Would love to see you do a video on the new US Dry Combat Submersible which just achieved IOC. And also the possibility of it being armed with Black Scorpion torpedoes.

You missed the post ww2 Dutch triple hull design of the “Potvis”- and “Dolfijn” class (Total of 4 built,, one survivor now part of the “naval museum” in Den Helder). Bottom two cilinders housed batteries and propulsion, top cilinder housing accomodation and weapon systems. Smaller cilinders forming pressure hull allowed for greater diving depth.

Thank you. Interesting.

Thank you As always :)

The Soviets gained much experience in building double hull designs from Germany indirectly with the type IX U-boat and directly from the type XXI U-boat. The project 613 (Whiskey class) submarine in particular was heavily influenced by the type XXI. The type XXI being the first post war SSK.

I would love to see a discussion surrounding supercavitating torpedos. Thank you!

Awesome!

I love your content! Would you please consider making a video on the Typhoon? I'm very curious about how the hulls are connected, how crew transits through the 5 hulls, what you suspect protocol was for sealing the hulls during battle stations, even what you suspect the diameter of each hull is as I suspect they are each actually narrower and less spacious per hull then a traditionally laid out SSBN considering the beam is 25m but there is a lot of space between hulls, etc. Very curious on your perspective! In any case, thanks for all the great content!

It's interesting that the soviet MIC was, as a trope, positioned for quantity and low cost in many cases compared to the west (tanks, small arms, etc.) but they went with double hulls on their subs.

Great video and well explained!! Always wondered the difference and pros and cons.

Do I ever!?! Getting in an argument online is a full time career.

I would like to hear more about France's "complicated case", did they do both types of subs?

That’s a cool shot of the stern of the twin screwed sub. It has like horizontal stabilizer or like elevator fin right behind the screws, almost like a thrust vectoring setup. I don’t think I’ve seen that before.

I think that double hull is now better because it can be angled for improved radar and active sonar stealth such as with the Type 212CD.

The other big advantage not usually mentioned is Single hulls are cheaper to maintain which is usually important when you have a big Navy such as in the Cold War. Soviet subs where often laid up in port waiting for repairs. Operationally Soviet boats went to sea less often. The Soviet Union collapse was greatly influenced by the cost of operating their Submarine force.

@HISuttonCovertShores >>> Great video...👍

I know nothing about this sort of subject but and find the information fascinating. Thanks for these informal presentations. I wonder if you might as part or whole of some future youtube chat about the trade offs for drone or autonomous underwater weapons related to maximizing the chances of sinking vessels mainly designed for hauling cargos. In the attack by a surface drone on a Russian vessel "Sig" a few days ago, the charge apparently was not shaped, so damage was less than would it have been if blast force was focused into the ship. Also, it was noted that the location of the strike might have been chosen to maximize the chance the freighter might break in two. I recall that charges for tirpitz were intended to maximize blast effect by seting them off under the ship in order to maximize chances this would severely damage the keel and other hull structures. I wonder what the sorts of approaches (type, size, and location of detonation), would be more optimal for an underwater drone or autonomous torpedo intended to sink a tanker, freighter or landing ship the size of the Sig.

Wonder if the “stealth” outer hulls will be composite to save weight and help make the sonar return.

Hi Mr h.i Hutton can you please do a video or videos on midget submarines and human torpedoes and combat swimmer's

Fuck it, we're going FIVE hulls!

I like double-hulled subs purely on aesthetic grounds. They look better. No other reason. :)

1. Is double hull like double-pane windows in that they're better at thermal and sonic insulation? 2. Is the outer hull also a pressure vessel or is it just watertight? 3. Does double hull act like a Whipple shield in case of shrapnel or other projectile attack? Or is that just not a factor since anti-sub weapons are all blast-based? 4. Does the outer hull give the sub more resilience to impacts (eg on undersea terrain, fishing boats, ice)? Thanks.

I would think that a double hull would just add another layer of complication. Meaning more individual spaces to inspect. But, with all the advancements in metal alloys and other chemicals, it might not actually be as much of an issue as I thought.

I was just thinking about stealthy double hull submarine and specifically if there's any reason you couldn't use the space for a flow battery anolyte and catholyte tanks? There's lots of research being done into different chemical solutions and membranes for grid storage but since they're liquids it would kinda make sense for subs.

I don't know if the youtube algorithm is single or double hulled, but here is a comment to fuel it nonetheless.

Can you make a video talking about the s80 class submarine?

Mr. Sutton,why do some submarines have their dive planes on the sail and others mounted on the hull?🤔

That was very interesting indeed. I'm just lacking someone to argue with... Any volunteers?

5:32 also shout out to North Korean domestic (non-USSR) submarines being mostly single hull (& midget) and on the double hull side, we have good guy countries like the Netherlands & recently Taiwan (which learnt from Dutch double hull designs), although i dont know exactly why the Netherlands chose to continue with the double hull design

So, out of curiosity is there a problem with barnacles or crustaceans growing between the hulls?

Crystalized: It is a case by case decision by the designers and engineers, what ever works best for their needs

Lets go back to back videos!!!!!! its 6:40 AM good morning dudes.

I like your last point. As stealth becomes more important in sub design, double hull will become more common.

“Double bull submarines can dive deeper” Well, that’s kinda true. You see, double hull allows you to put stuff that you don’t need to be pressurized, outside of your pressure hull. What this means is that you can get away with building a smaller pressure hull for the same functionality. As the result, you can afford to make that hull thicker and therefore dive deeper.

Yaas!

Double watching vs single watching submarine videos.

@HISuttonCovertShores 5:30 What about Japan and Spian subs?

I tend to think of double hulled as those made up of smaller bathysphere like modules encased in an outer hull for streamlining as opposed to single hulls which are a single cylinder broken up by internal bulkheads. Pretty much every single hulled submarine has some degree of external equipment whether its cheeks, just on top or almost completely encompassing.

Somewhat unrelated question for H I Sutton. In the recent internet deluge of "expert opinions" on submarine and submersibles, a retired US Navy submariner was quoted a saying the rate of dive affects the crush depth. Is this true? In know that the strength of steel or titanium is measured by slowly stretching or bending a sample (low strain rate) and the impact resistance (toughness) is measured by hitting a notched sample very quickly with a falling pendulum (high strain rate). It is hard for me to imagine that a submarine can dive fast enough that the materials experience the high strain rates of a Charpy impact test. Of course toughness would be important to resist underwater explosions and shell impacts.

are the double hulls linked? ie can crew go between both??

"Water on the outside, people on the inside" Ooohhhhh so that's what I've been doing wrong all this time.

I would have assumed that double hulls would be quieter or atleast have to potential to be easily made quieter because sound dampening could be placed between the hulls.

It was my impression that in a true double-hulled sub both hulls contribute to the strength of the pressure hull. In other words, both hulls are load bearing, in contrast with submarines with some non-structural external casing that's there for hydrodynamic or acoustic reasons.

Haven watched the video yet but my take is it doesn't matter. Much more important is how quiet the submarine is and how good its sensors are.

"But this is useful information of you ever want to get involved in an argument on the internet or something else important like that" hahahaha Self deprecating humour and not taking yourself and what you're saying too seriously speaks so well for someone's character in my view. It genuinely makes me take what you're saying more seriously.

So if i can move equipment outside the pressure hull with a double hull design, then for the same internal usable volume of the pressure hull, i could have a smaller radius tube. Doesn't that mean i get an advantage in weight for the design to reach a specific deeper maximum depth? Double hull comes with a weight penalty, but boyency wise, you could more easily have a very deep diving design to be safely boyent with smaller hull(s)

So each type has advantages, but why exactly did the various countries go with the type they did?

8:07 what is more efficient? i mean about what efficiency do we talk about where double hull is more streamlined?

I was thinking that a double hull is ok if you cannot ensure that the cylindricity of the pressure hull for a given diameter. The smaller the diameter of a pressure vessel for a set thickness, the larger internal or external pressures it can take. Though I guess the stiffeners can strengthen it. For something like the Typhoon, it is more practical to have essentially two large pressure hulls and a launch complex inside a flatter cylinder instead of one very large circular hull.

Wouldn't a single hull lend itself to a quiter boat due to stiffness and rigidity? The outer hull/casing of a double hull is going to be less rigid and stiff as it doesn't need to withstand diving pressures, therefore more susceptible reverberations. I guess what you're saying is ultinately correct though - it's the sound deadening technologies that drive down the quietness.

single hull is tracked back to the HL hunley era EH

Heads up, your description says both 'sides' use double hull.

Outer hull can absorb some of the blast shock reaching inner hull

Video/Article idea/topic: Air management in Submarines. Both Nuclear and conventional submarines need to provide a breathable atmosphere. Nuclear submarines as far as I know, use electrolisis as well as CO2 scrubbers powered by their reactors to extend divetimes indefinitly. Do AIP Submarines have any technologies that extend the time between needing to replenish air? It was eluded to in the AIP video I belive.

Regards the myths, I wonder how much of that came from the Tom Clancy era?

Have you made a video about how submarines control buoyancy ? ?

So, the hulls systems doesn't affect the noise levels?

I've heard the big Soviet double-hull boats (Nato-code Tyfoon etc.) which had the reputation in the west of being able to take a single torpedo hit and survive couldn't due to the venting system connecting both hulls. Does anybody know if this is true or not?

Next, pros & cons pump-jet propulsion. And why there's no double pump-jet propulsion ? 😊

There is another reason why the German Type 212 is of a double hull design, other than stealthyness. The hydrogen used to power the fuel cell is stored in between the two hulls, thus keeping them outside of the crew compartment (for quite obvious reasons since hydrogen is known to go boom easily and violently 😂).

I'm really struggling to answer that on my own, pre video. I've never really considered one better or worse out of any other context. I've always simply thought of it as an engineering answer balancing cost and build time, that you try to get away with a single hull if you can, but eventually it isn't worth it. I'd imagine cheap labour helps the balance immensely. Perhaps I'm wide of the mark before watching, but I don't see how it affects their operational capabilities. Perhaps double hulls are easier or conversely more expensive to maintain? I have no clue. My gut says to a torpedo there isn't much in it, but it might be better in bangs and scrapes. Though they are usually in places that don't make a difference. Also it's too hard to account for things like size difference and detectability. I'm not sure I could give more than a null hypothesis. Even with aircraft in ww2 there are thousands of aircraft produced and lost and drawing these conclusions is tough. Perhaps the crew feel better with two?

3:27 Would you happen to be color blind, or just misspoke? Because that is not a green line on the outer hull, that's most definitely yellow...

0:21 showing a Akula might be a bit missleading as it has actually 5 pressure hulls 😂

Thank you for the info. How about Japan and ROK built submarines?

Is no one going to point out that the "green circle" is actually yellow?