Boats

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(This section should be titled "Ships" since the only people who live in large numbers for extended periods in the open ocean on "boats" are submariners.)

"Why not just buy a boat"

This is answered in the FAQ.

Counterargument in favor of ships

First, seasteads need to work with ships in order to transport goods and people to and from them. Seasteads probably would not be able to operate for very long without the support of ships (unless people really liked a diet heavy on sashimi). Seaplanes are faster than ships, but much shorter range and not as cost efficient for transportation of bulky or heavy items like food or machinery.

Second, it may be possible with novel ships designs to meet more of the desired criteria for seasteads such as lessened wave coupling, large solar area, broad and open living areas, lower cost, etc. The greater mobility of a ship over a seastead can be an advantage for travel, trade, fleeing from attack or approaching storms, change of scenery, meeting new cultures, etc.

For example, the proposed HARTH design was removed from the Seasteading book draft, presumably because their claims for a drag reduction technology seem unlikely. But the general shape of their ships, sort of like a large catamaran, lends itself to large solar area and broad living spaces. HARTH ships are different from catamarans in that their hulls are shaped to interact minimally with waves and to stay mostly submerged. Waves would see a very narrow and shallow cross section due to the high aspect ratio and shallow draft of the submerged flotation hulls. If the floats are more then 300 meters long then typical long period ocean waves won't affect the ship very much in head or following seas. HARTH technology is largely unproven except for a 27 foot model, and the claimed drag reduction technology may not have appeared on an actual vessel yet. The model video, possibly shot in Puget Sound, may look positive.

If a HARTH type ship did not have drag reduction, then it would lose the claimed speed advantage but it would still be relatively fast due to using high aspect ratio (i.e., narrow) displacement hulls. Even without high speeds due to drag reduction such a ship could be an advantage over exiting designs in areas we care about such as reduced wave interaction, large usable area, etc.

Finally, simply being on the ocean is a major step into freedom, whether it's on a ship or seastead. Ships may also make a logical testing venue to try out some of the possible business models for seasteads even before any seasteads are built. SurgiCruise is an example of a business that takes advantage of the lower regulatory costs of using ships in near-offshore waters.

Even without any new ship designs, exiting large ships could be used to live on the ocean and/or to support seasteads.

A partial list of some existing surface ship types

  • Displacement hull - pushes water aside like a plow
  • Semi-planing hull - characteristics of both a displacement and planing hull, transitioning to planing with increasing speed
  • Planing hull - rises out of the water as speed increases, nearly totally in some extreme cases such as racing boats
  • Hydrofoil - uses underwater foils (like wings) to lift the hull usually completely out of the water, but only at speed
  • Hovercraft - uses fans and curtains to create a cushion of air between the hull and water
  • Catamaran / Trimaran - has multiple, parallel displacement hulls supporting a cabin above and out of the water
  • SWATH - submerged twin hulls with active buoyancy control and reduced waterplane area, both to reduce wave interaction
  • Surface effect ship - has sidewalls like a hovercraft but traps air under the hull when moving by having an open front

More links and info:

  • Boats for sale
  • Government buy-back programs exist that lower the "value" of a vessel because it is no longer allowed to be used in a commercial fishing enterprise. These vessels are usually displacement hulls, which give a greater internal volume per surface area than some others- this leads to greater drag, lower speed, but more cargo capacity. this might also be of use to the Sea Steader in that the sea being a harsh and onforigiving element, a great deal of protection from your environment is necessary. Some
  • Ship types in wikipedia


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