SFRPG

As you can see from my various posts on this subject, one of my "technology
bugbears" is a plausible method to establish a first "beachhead" for the coloni-
zation of a water world without any land, a first base where the colonists can
start their project and begin to build the basic infrastructure (e.g. habitats, ve-
hicles, etc.) required by the colony.

This is made a little more difficult by the facts that my setting uses a compara-
tively "hard" science fiction technology, without gravitics and similar "magical"
technologies, and preferably also a "low cost approach" which makes it possible
for a group of private citizens to finance the project without much help from a
government or a corporation.

My previous ideas for a solution of the problem tended to be rather expensive,
mainly because I wanted to land a complete floating base in one piece, either
as the payload of a "dead glider" or with a spacecraft able to land on water -
and to transport such a base in one piece or as a number of easily assembled
and therefore rather big parts would require a lot of expensive cargo volume.

My latest approach to the problem seems to be less expensive and more easy
to handle: Temporary "Air Mattress Floaters".
Such a floater, shaped like a big raft with several "air chambers" and with so-
me keels to stabilize it, would consist of a "hull" made of a heat and flame re-
sistant metallic foil. It would be transported and deployed "folded up", as the
payload of an orbital drop package consisting of a reentry shell and some pa-
rachutes.
After landing on the ocean surface the orbital drop package would release the
"air mattress", and an automatic system would use pressured air to unfold the
floater and bring it into its final shape. Then the system would fill the cham-
bers of the floater with an aerogel-like foam, and once this foam has harde-
ned the floater would be ready for the landing of a VTOL spaceplane or Roton
with the first group of colonists and the construction materials and parts requi-
red to start the colony project.

Such an "air mattress floater" would probably only survive a small number of
landings and take offs of VTOL spaceplanes or Rotons, but I think it could sur-
vive long enough to serve as a temporary "construction site" for a more perma-
nent interface facility for the transport of personnel and supplies from the pla-
net's orbit to the planet's ocean surface.

Well, that is the basic idea - but could it work and does it make sense ?

Thank you very much for your comments and ideas.

Because I'm currently working on a low(ish) technology colonization project of what is essentially an water world I've been giving this some thought. I think the colonization requirements of my world are going to be different from yours, but I've been considering something similar.

My main concern with your air mattress floater is what happens if a storm hits while it is deployed. Unless it's easy to set up and take down, things are going to get unpleasant, especially at night when oceans tend to get higher waves.

I've read things about ocean waves recently that have totally made me revise my (erroneous) beliefs about waves before - I used to believe that high waves mostly only occurred near shore, where the wave cycle drags on the seabottom and so on. But apparently large swells occur regularly occur far out to sea and dangerous phenomenon like rogue waves and so on do exist. Also, on an ocean world, I'd think storms would really grow large and powerful. This, I think, makes early colonization using ocean surface platforms overly difficult as the colony will have to regularly deal with these material stresses and damage at a point where the colony can ill-afford damaged equipment.

There's three ways around it, I think. The first is to get materials that are sufficiently strong which is sort of the brute force method. I'm not really sure how well that'll work. So I'll table that for now and put it in the fantasy realm of the mature colony.

The other two methods involve minimizing the area of the colony facility to ocean conditions. One way would be to simply stick them on pylons like oil rigs where the pylons limit the area of the rig in direct contact with the sea. The other way would be to make the entire affair submersible.

My concept for a landing site would be the initial colonists to land in floating vehicles. From there, they could deploy the molds and rigs involving the use some of sort of chemical that would react in the presence of something in sea water to foam up (there's a few candidates for this stuff even now, but I figure in the future such materials could become even better and more useful). It'd be much heavier than airgel but also stronger and rigid, allowing it to support weight. The resulting material would be fairly durable and flexible, but still be mostly air. Once cured, the material would be fairly easy to work using tools to form rooms and so on. It would be, by definition, buoyant so essentially unsinkable. It would be formed into the desired shape by crude molds to get the overall shape, with strong support beams inside to provide strength and anchoring points. Multiple floats would form the initial platform. The entire structure would be secured to the seafloor by means of cables, which would be useful for keeping the platform in a single place but also to pull the platform under the sea surface by brute force in the case of storms.

While it sounds like a wonder material, it'd probably be biodegradable over the course of years if exposed to UV radiation, so the colonists would coat any pieces they didn't want decaying with paint or something similar. Pounding by the sea would eventually cause the material to fatigue as well, but the builders imagine the platforms will only need to be useful for about five years at most before replacement, either with a new foam facility or (hopefully) something more permanent. It definitely wouldn't handle the hot exhausts of rockets well. Any landing facility would need to be protected, probably using a combination of a hard thermal reflective material along with a system of heat sinks to transfer heat to the ocean water.

My idea to deal with the problem of bad weather and waves was to land
the original floater near the equator in the doldrums during a period of re-
latively calm weather and low waves, which should be possible to predict
from an orbital position. With the temporary floater as the base and con-
struction site, the permanent surface installations and vehicles assembled
there to replace it would be of the SWATH catamaran type, a design es-
pecially useful in bad weather with high waves. However, most of the ac-
tual colony would then be constructed on the sea floor in the next phase
of the project, where it would be safe from wind and waves.

http://en.wikipedia.org/wiki/SWATH