From: jrm@gnv.ifas.ufl.edu
Newsgroups: sci.space
Subject: Re: Inflatable Space Stations - Why Not ?
Date: 21 Aug 92 23:50:03 GMT

In article <RUCA.92Aug20135422@pinkie.saber-si.pt>, ruca@pinkie.saber-si.pt (Rui Sousa) writes:
> In article <1992Aug19.183403.1527@gnv.ifas.ufl.edu> jrm@gnv.ifas.ufl.edu writes:
> 
>>    Whatever became of the idea of inflatable space habitats/workstations ?
>>    The savings on initial cost and on launch weight should be very great.
>>    Add to that the large size and configurational possibilities and you
>>    have an incredibly good deal. Modern materials, esp tri-weave carbon
>>    fiber, could strengthen an envelope and protect against ripping or
>>    [...]

> Well, I think NASA has been doing some nice research on how several materials
> cope with LEO atomic oxygen and radiation. If it turns out those THIN walls
> can't do it, it would have been too soon to talk about inflatable structures
> ...
> Despite that possibility (I hope those materials can do it) the idea seems fascinating from the ecenomic point of view!

	I have heard a number of people claim that atomic oxygen would
	be a problem for inflatable space stations. While this is a
	very reactive substance, I cannot imagine that a suitible
	protective coating is unavailible. Even a few microns of
	vapor-deposited gold should supply considerable resistance
	to atomic oxygen. Vapor-deposition also allows stuff like
	silicon dioxide, aluminum oxide or other ceramics to be
	'painted' on. I have never seen any reports about how well
	stable plastics like teflon cope with O-1 ... though you 
	would have to overcoat it with aluminum or gold to keep
	the UV away. 

	If O-1 is such a stickie-wickie though, the obvious solution
	is to opt for a higher orbit. Proper disposition of equipment
	and water/fuel chambers around the exterior perimiter would
	give considerable radiation protection - probably better than
	for 'Freedom'. At a higher orbit, these large-volume
	structures would be ideal 'warehouses' for spare materials
	and could be used as a refuge in case some prob made it
	impossible to leave orbit in a shuttle - stuck doors, main
	engine failure, heavy tile damage etc.. 

	Anyway, this idea, or slightly armored versions of it, seem
	so incredibly economical and simple that only evil politics
	could be behind their suppression - not engineering probs.
	One poster claimed to me that Livermore Labs had claimed
	inflatables could supply all the functionality of 'Freedom'
	for 1/10 the cost ... and they were told to butt out. With
	money tight - it is obvious that there is a lot more interest
	by contractors in stealing every availible penny of govt
	money they can than there is a dream of a new frontier. 
	Ten 'Freedom' equivalent stations instead of just one
	ultra-expensive, vibration-plagued, ultra-custom station
	would do a lot to further the utility of space. 

	Write your congresspersons and senators ... tell them you
	have heard of this better way ... tell them you are 
	disinclined to vote for people that spend ten times what
	is required for projects. The incumbents are more afraid
	for their jobs this year than in a very long time. Voter
	leverage is magnified. Take advantage.

-- Jim Mason
Newsgroups: sci.space