From: The Butterfly (salsbury_at_bootstrap.sculptors.com)
Date: 04/17/98
Date: Fri, 17 Apr 1998 17:29:51 -0700 Message-Id: <199804180029.RAA19090@bootstrap.sculptors.com> From: The Butterfly <salsbury_at_bootstrap.sculptors.com> Subject: Re: floating houses / floating villages
Please note: This post originated on the airships list, but I'm
CC'ing it to the floating-cities list, for obvious reasons. :-)
I'm not sure exactly how the list software will deal with replys to
this, but I suspect that it will probably direct the post to the respective
list that you're on. If you're not on both, you may see weird errors about
not being able to post to the list you're not on, and you may miss some of
the thread. You can sign on to either list by sending a note to
<listname>-request_at_sculptors.com and putting "subscribe" into the Subject:
line.
Pat, always playing around with the list software to see what breaks. :-)
-Date: Thu, 9 Apr 1998 11:22:02 -0700 (PDT)
-From: joshua geller <dclxvi_at_best.com>
-Reply-To: airships_at_sculptors.com
-
-Chris McCoy writes:
-
- > If I recall correctly, the Hind.. had a helium lift of 65 tons, and a
- > hydrogen lift of about 70 tons. If you build a ship that size
- > today, with modern materials, you would have far more payload.
-
-the requirements for a floating town and for an airship for
-transportation of people and goods are different. I'd scruple to call
-the floating town an airship; I wouldn't expect it to navigate so much
-as direct its course with the wind. a sphere or a lenticular hull
-should be fine; you'd want to make it plenty big. this would be a
-giant rigid balloon, but not a dirigible balloon. I'd say a two
-thousand foot sphere or a suacer appreciably larger than this would be
-the minimum practical size. you'd have flattened ovoids four hundred
-feet long for tenders; probably at least two of them.
-
-really, with airships, bigger is better.
This meshes EXTREMELY well with the the concept Bucky Fuller put
forward for "Cloud 9" cities. These were to be gigantic (.5 miles or
larger in diameter) geodesic spheres with entire cities inside of
them. They weren't to be standard helium-filled airships, but would
actually float due to the differential air pressure created by heating a
volume of air that large. Like a hot-air balloon that's a mile or two in
diameter...
- > Concievable, you could put a small community of 5-10 families up
- > indefinitely. The difficulties are maintenance, long-lasting
- > materials, and power.
-
- > Maintenance could be performed by the collective, but if you have 20
- > adults and you need to run a hydroponics farm, service equipment and
- > maintain materials, you pretty-much max out your workload.
-
-I wouldn't think of something like this outside of the context of a
-global civilization; food will be brought aboard on the tenders, as
-will anything else that you need from the outside world. I'd imagine
-that these would be specialized communities of people working on
-something that they are as a group interested in.
-so no hydroponics farm.
I'd disagree here. And I'll reiterate a design I proposed on the
GEODESIC list when we were discussing sky-cities back around 1989.
Imagine a sphere. A really, really BIG one. Using geodesics, you
can build something incredibly strong, yet extremely lightweight. The upper
half would have transparent materials to allow sunlight in, and even the
lower half would have the option, so you had "windows" looking down towards
earth.
Starting roughly at the equator of the sphere, and working
downwards, on the inner surface, you build your city. Buildings, houses,
villages, community centers, parks, etc. All sloping downward in a huge,
circular bowl. At the equator, and above, housing would be similar to
high-rise apartments, with stupendous views, but little to no yard. Near
the bottom, the ground would be almost flat, giving space for recreational
areas, markets, etc. Any place you want, in any apartment, the outer wall
can be made transparent to provide views of the earth below you.
At the very bottom of the sphere, in the center of that bowl-city,
would be a very large open hole. Perhaps 400-500' in diameter, perhaps even
more.
This hole, aside from providing stupendous views at the perimeter,
would allow cargo-carrying airships to come and go, and provide "safe
harbor" and reasonably still air for docking, loading, unloading, etc.
Now zoom back up to the equator of the sphere. Build a floor across
at the halfway point, bisecting the sphere into upper and lower
hemispheres. You can put similar holes through the floor, if airships need
to get to the upper part. On the top of this "floor", you can plant crops,
since you keep the upper part of the dome transparent. You can also do
hydroponics just about anywhere else, horizontal or vertical, with natural
light, or artificial, but just going with this "floor" at the equator,
you'd have lots of space.
Let's say it's a 2 mile diameter sphere. At the equator, you'll
have A=pi(r)^2, or approximately 3.14159 sqare miles of area for
hydroponics.
You can support an average person for an indefinite period of time
with the amount of food grown in 125 sq. feet of hydroponics. (See "Ho
Ping: Food For Everyone" by Medard Gabel and the World Game
Laboratory. It's available from the Bucky Fuller Institute -
http://www.bfi.org/) This is total support, meaning they could live off
just the food produced there. If the hydroponic diet was supplemented with
meat imports or whatnot, then you'd need less space per person, but you'd
have added import costs.
One square mile is 27,878,400 square feet. (5280^2) That means that
oe square mile of hydroponic farms could support 233,027.20 people,
roughly. That means that our "floor" area of 3.14159 square miles yields
87,582,502.65600 square feet, with a rough feeding capacity of 700,660
people, which is roughly the population of San Francisco.
- > Materials are the big question, as I am not sure how long mylar would last
- > in a high UV, low-pressure environment 30-40k ft up.
-
-I think aramid films or something better that I don't know about would
-be the choice, not mylar. don't worry about expense; this is a
-multibillion dollar project, here. this is not something that is
-happening this year or next year. twenty years down the road when the
-companies that come out of this group are multinational corporations
-there will be money for this kind of project; don't expect it to
-happen before that.
As noted before, tefzel might be a good candidate. I'm also
researching rigid panels of some sort of polymer, filled with evacuated aerogel
for insulation. (This yeilds an R-factor of about 32 per inch of material,
while maintaining transparency.) If others are interested in this aspect
(any chemists or materials engineers out there?) I can go into more
detail. This is a whole company unto itself, and would, as noted above,
have multi-billion dollar contracts from projects like this. It would be an
excellent thing to have in the Reality Sculptors Project...
- > Power ideally would be collected by solar, stored in large flywheels, and
- > backed up with a methane-burning generator. The generator fuel can
- > be produced by the hydroponics farm's waste. An atomic reactor is
- > also an excellent power source, as helium is the by-product of a
- > fission reaction, power and lifting gas from one source.
- > Unfortunately, I know of no person who would be comfortable with a
- > atomic reactor flying over thier head.
-
-yeah, a whole bunch of attitudes will have to change before this is
-possible. it might be possible to do it with solar and flywheels and
-such.
Solar is obvious. I'd still push for fuel-cells, and we just happen
to have a fuel-cells mailing list in the Reality Sculptors Project... :-)
Perhaps if there's interest, folks here can join there, and we'll continue
the talk in that venue...
--
Pat
___________________Think For Yourself____________________
Patrick G. Salsbury - http://www.sculptors.com/~salsbury/
Check out the Reality Sculptors Project: http://www.sculptors.com/
---------------------------------------------------------
We've got less than 15 years left... ;^)
See http://www.sculptors.com/~salsbury/Articles/singularity.html