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Semi-Submersible ??

Home Forums Archive Structure Designs Semi-Submersible ??

This topic contains 16 replies, has 12 voices, and was last updated by Profile photo of chadsims chadsims 4 years ago.

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    Profile photo of Josh

    Is there a reason Semi-Submersibles are not being considered? Drug runners have been usinging homemade ones to get past the Coast Guard. They are being made out of fiberglass and wood in mexico and south american often in the treeline on remote beaches and then being heavly loaded with cargo (coke, ect), navigated in coastal waters and the open ocean. It seems that they would satify all needs for a seastead; mobile, stable in rough seas, easy to build using the same technics used to build sailboats, and I am sure they could be made modular (perhaps set up in a line like a train). The smugglers use them because they are hard to spot, which would be idea for a seasteader trying to avoide being harrased by a pirate. Large waves wash over the craft. It seems to me you could get most of the beifits of a submarine and a boat out of one vessel.


    Profile photo of Melllvar

    For one thing, water pressure increases by approximately 1 atm per 10 meters in the ocean. So instead of needing a sturdy structure to withstand waves you need a sturdy structure to withstand the constant water pressure at whatever depth. Now honestly I haven’t bothered figuring out what causes more force on a hull, water pressure at x depth or waves of a given size. I think the general assumption has been that waves are easier to deal with than water pressure 100+ m down.

    Even if it wasn’t, people would need to compress and decompress when coming or going. This would probably mean decompression chambers, although I don’t know at what pressure difference such things become necessary (as opposed to just exhaling as you surface). Plus you lack a deck, sunlight, easy access by boats, easy access TO boats, etc.

    Waves also continue underwater, eventually diminishing with depth, so considering that and possible 30+ m wave amplitudes, you’d have to get pretty deep to avoid them. You couldn’t just sit 10 meters below the surface and expect to miss them.

    I believe enclosed hulls on the surface (like a floating submarine) would work better, there have been a few threads about this version recently. There’s also some other semi-submersible threads floating around, and stuff on the wiki about them. Underwater cities (e.g. Rapture) would be pretty cool, but I think they’re much farther off than surface seasteads.

    Profile photo of Josh

    Semi-Submersibles do not dive or decompress, they are basically a boat that sits low in the water. they gain stbility by cutting through big waves not going over them. They have a deck, they just can only be used in calm seas (like every other boat). Ballasts are used to adjust how high or low the boat rides, almost every large boat uses some sort of ballast.

    Profile photo of Melllvar

    Sorry, it seems I completely ignored the semi in semi submersible when reading your post. Wow, I feel profoundly ignorant now.

    I’m not able to give a good answer to the actual question (as opposed to the question I invented in my mind). A partial answer would be that the design is similar to the spar design (i.e. ClubStead), which has its own disadvantages (and advantages). I’m pretty sure more work has been done on that design than any other, at least by TSI. Viewed as floating platforms, they are fairly similar, so the spar design was probably chosen first for in depth research (couldn’t say why, out of my league). Floating platforms of any type are going to be expensive, since they need big columns to support a lot of weight, which would be another reason you don’t see anyone rushing to build one.

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    Somehow a seastead that is mostly underwater does not appeal to me. Also, I think it would still be quite affected by waves.

    Of course, a semisub can mean a lot of different types of vessels, so I wouldn’t say the above applies to all of those.

    Profile photo of faena

    Josh wrote:

    Is there a reason Semi-Submersibles are not being considered?

    I was talking with a sailing forum about semi submersable sailboats and one of the non joking commentators suggested i use animal basics for my ideas. the only sailing sea animal i know is the portugeuse man’o’war. and it is semi submersable! i don’t see why this sort of thinking would not be valid for seasteads. i am making my own trimaran from lastest fiberglass tech and find it very fulfilling. it is rather low profile anyway. but it is made to move very fast, hence a huge mast. my thinking is a low profile boat with multi masts that are retractable. my trimaran is also trailerable so the outer ama, or pods can be pulled into the boat; very handy. the pods can also be flooded to help stabilze the boat in rough weather inshore. this is as far as my thinking has allowed. an older vision was to have a geodesic platform over a reef; sort of like a garage. but damage to the reef would be intolerable in my view. a floating geodesic platform would be nice; maybe with a series of sea anchors?

    i have always thought the form of the catamaran resembled a manta ray. wouldn’t that be fun; to move like a manta ray?

    “If you don’t stand for something, you’ll fall for anything.”


    …don’t like submerged…

    I doubth like you, that there will be a lot of people that voluntaryly adopt submarine confinement as a desireable syle of living.

    It may be one out of hundred who really would like to live disconnected from the surface, producing oxigen from the seawater wandering submerged and seperated from mankind trough the worlds oceans captain nemo style.

    The typical owner would handle a submersible living space bubble habitat (i avoid the word submarine due to the misleading coffin perception) as a simple yacht that is in almost all of its aspects a yacht, just absolute storm safe, seasickness free, burglar safe, and maintenance cost free.

    Like other yachties you would not be the whole day enclosed inside your boat. You would form part of a yachtie community anchored in the bay of a caribbean island.

    In the morning you would row over to the beach meet with people from the other boats, have a beach grill, a coconut, a island adventure – you would only return to your boat to have a pleaseant night sleep in a king size bed and a freshwater shower.

    There are differences in lifestyle to other yachties. For example when you leave your boat in the morning (all of your family – nobody wants to stay and watch the family home) you just close the hatch – so your living space becomes absolute burglar safe.

    The other yachties always live a bit preocupied about their boat, is somebody breaking in to steal your nav equipment?, is the weather on the anchorplace changing smashing the boat against the reef?, – so they tend to live “in sight” of the boat.

    You on the other hand, when get an offer for this dream on week trip – take it – when you return you will find your stuff well protected inside your living space bubble – just exactly as you left it there – breaking in trough a hatch is like breaking into a banksafe – nobody can deploy the necessary (heavy industrial) tools on a anchorplace.

    Another situation where your life is really different to a yachtie is when you are together with several sailing and motor yachts anchored in front of this pristine beach of a unhabitated island. Somebody has a radio and spreads the news that tropical cyclon Bertha category 4 is closing in. Now it becomes clear why this beautiful island was uninhabitated in first place – no save harbor miles around.

    Some yachts rush out into the dark of the night to make it by the speed of their expensive engines to the next safe spot – just to find that it is cramped with poorly anchored industrial barges that tend to come loose in a storm and grind everything in their way to pieces.

    Smaller yachts send the kids for the nearest hotel to be safe and go for the mangroves to bring out several lines to the trunks and fight it out. They can make it as long as the storm surge is moderate.

    You on the other hand just close your hatch drink a coffee watch TV – no need to leave the anchor place. If things become bumpy flood your ballast tanks and lay your bubble some 5m down on the sandy lagoon bottom until the storm has passed over you. You and your family are safe as in a underground bunker.

    You could take advantage of the shit weather and the sudden absence of all your yachtie friends and make a few miles to visit the next spot. You sail out directly into the storm – trim your living space bubble at snorkel depth – you leave the coffee cup on the table, you watch the weather the sea and ship traffic with your snorkel top camara – but your comfort is not affected by the storm.

    Your live will also be a bit different when aproaching a cramped marina with no space for “another boat” – you will always be the “most exotic boat” that draws the attention and marina owners will love to asign you a nice place to stay – maybe for free. While it may be difficult to have privacy in a cramped marina on a surface boat – you close your hatch and you have it.

    Your living space bubble will also be different in terms of aircon, comfort electrics, and loading capacity.

    For example a yacht in the caribbean can spend dozends of dollars a day in aircon to make the climate below a sun heated deck just bearable. The seawater around your hull maintains the inside at 22 degee with no aircon need.

    Yacht owners sometimes go crazy with the vibrations and noise of the small generator that keeps the battery and freezer alive. Noise dampening and vibration is most of all a function of bulkhead weight – bad news for “leight weight yacht outfitting” – you have your generator behind 20cm concrete – complete silence guaranteed.

    Yachties are always short of loading capacity for freshwater food, tools, equipment.

    You on the other hand have dozends of tons loading capacity this gives you not only the freedom of a much longer range compared with similar sized surface yachts – it also allows you to make a living as a trader – moving cold beer in hotel quantity to remote locations.



    European Submarine Structures AB


    Any interior design seen in business jets or yachts is possible – plus a whole lot more – as you do not have strikt weight limits in a submersible living space bubble. So feel free to add a jaccuzzi – also there is no need to bolt everything down as the living space bubble stays on “even keel” under all ocean conditions this opens the possibility of using standard chairs and other off the shelf solutions form the standard housing market.

    To get a picture how big the living space inside a submersible living space bubble is, how light comes in, check this video: http://www.youtube.com/watch – notice that light comes from above what makes interior design much easier than in a business jet (much less artificial light required)

    We can do the hull for 331 Euro/ ton of displacement. The hull seen in the video above (18m / 200 ton) is for 66.200 Euro –

    In general terms “semi/submersible living space bubbles” seem to be a great and economic way to independent mobile seasteading taking weather and wave concerns out of the equation allowing scaleability from mobile home size to city size.



    Profile photo of shredder7753

    Wil – the sales pitch is interesting. anyone can see that you have a niche, and that you’ve developed a compelling story… NOW, you have to determine as many potential consumers as possible. you need a target market. write down on paper what kind of people you think would have the means and the POTENTIAL interest in this product and GO AFTER THEM. GO AFTER THEM! :-) hunt them down and make em say “please”. be a damn sales person god damn it! in my opinion it may not be a mass market item but you have to reach out to the right people. you have to sell yourself along with the product. convince them that you have what it takes to not only sell the story, but you also have the where-with-all and the means to make this product a reality – AND stand by the product once they are using it. they need your confidence. they need your reassurance. they need you to beat them into the ground until they cant stand not having your amazing spectacular awesome tremendous fantastic useful enriching product!

    “There’s no way we can out-class the Jones family until we get one of those incredible Wil-Stead’s!”

    make them feel like a winner for buying into your vision.


    My work

    “Leadership and do-ership are not the same thing”

    Profile photo of elspru

    Semi-Submersible Safe.

    All biological bodies have the capacity to maintain their own internal environment,

    and to seal themselves for at least temporary submersion.

    All seasteads by analogy corollary should be able to handle tempororary submersion.

    For instance if in a hurricane force storm or with rogue waves, there may be temporary submersion,

    even if the boat was to be flipped over, it would have to remain afloat.

    I also advocate being able to exit from the aft of the boat,

    much like how a fish can give birth, the womb would be an airlock.

    This is useful in many cases such as a flip, covert operations or heavy weather.

    With the airlock it also makes it possible to escape from a submerged vessel.

    Personally I would also advocate that all life-support and boyancy systems have manual controls, including the air-locks.

    so that the last-person to exit the vessel, could also operate the air-lock from the inside if need be.

    having a crouching space port air-lock at the fore could also be good, I advocate having it near the bow of the boat much like the mouth.

    Basically I imagine a boat as someone floating upside-down.

    Taking the analogy further then a standing room womb airlock would best be situatuated as the “cockpit” or vagina genital area of the vessel.

    Though it is common for many people to control their boat from their genital area (cockpit) or even rectum (poop deck).

    It makes much more sense to have the eyes at bow or head underwater as that is where the majority of obstacles are,

    we could have multiple windows in the bow control room like a spider, some windows can give above water views.


    calm aware desire choice love express intuit move

    Profile photo of painlord2k

    I would like to attract attention to the e-cat technology. To me this appear a perfect fit for a ship, surface, submersible or semi-submersible.

    If it is delivered (October), the inventor told that power plant, train and ship would be easy to adapt to use it.

    Profile photo of flash3780

    A semi-submersable seems like an interesting idea. That is, if it were massive enough to make the response to wave forcing (bobbing) a non-issue (which could be pretty massive).

    I was envisioning a multi-story cylindrical structure with a hemi-elliptical, glass roof. I’d also guess that you’d want a hollow of the cylinder to allow sunlight to penetrate down to the lower floors, and to ensure more weight at the bottom of the structure.

    That said… I’m not sure that the cost of going under the waves is necessarily lower than that of slowing the waves with wave-breaks. Perhaps a multi-family or multi-business structure that was three or so stories tall might be workable…

    Semi-Submersible Cylindrical Living Space

    It might be cool to look out your living room window and see under the surface ocean…. yet look upwards and see the sky.

    Profile photo of chadsims

    Beautiful consept. I can just invision it. I love the way you think. And to create cities, they could connect side by side. You get enough of them togeather like that you’d litterally NOT gett water on the ones at the center. As it builds this could possibly lead to a sort of natural island at the center, build it up with something a bit taller to create a park area for the comunity or something like that. I can see it now. I’m with you on this.

    For t he glass i’d suggest the real tough stuff, so if a HUGE wave goes over you it can handle the pressure of being submerged for a bit. 50FT deapth rating possibly just to make it so over the top as to be ‘unsinkable’. (Quotes because nothing is unsinkable.)

    ‘Lead, Follow, or get out of my way.’ -Unknown

    Edit: Squared with rounded corners for appearance, and if you devide it equally in fours you could make each one for a family. So four families could go in on one of these, or two and spilt it in half. (I like symetry)

    Profile photo of chadsims

    This as a top veiw. The four walk ways crossing to allow four way connecting hallways for people to move between steads without having to get above water. The walk way should either be made out of or partially one way glass like meterial so that sunlight can still easily reach the bottom layer, (along the edges of the four houses). I removed the third story and figured leave it empty except plants and grass, it’d provide garden or yard space for every seasteader in one of these, The weight of dirt should replace the building materials of a third layer, and you’d go abit to make them self sufficent, wouldn’t do it on it’s own, not enough space but would help provide nice vegitables and keep the air clean. (I know it’d get air from above, but what happens during a storm? Basic scrubbers or plants, both will extend your underwater life expectancy, I’d do both just incase, the plants should be plenty for the whole thing,t eh scrubbers for emergencies.

    According to the Arbor Day Foundation, “a mature leafy tree produces as much oxygen in a season as 10 people inhale in a year.” Not sure we’d go with trees but their’d be room, and it wouldn’t be allowed to grow to big in any case, BUT their’d be other plants that would help. The plants could do the job themselves. Even if it’s just grass and flowers.

    “55 square feet of turfgrass provides enough oxygen for one person for each day”

    ‘Lead, Follow, or get out of my way.’ -Unknown

    Profile photo of Sam7

    Bravo- Flash3780, you are on the right tract.

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