: Does anyone know any of the physical properites of the foam used on the
: heat shield? Is it some kind of foamed ceramic that is real light and
: fragile. I recall NASA making sure the astronaut not bumping into it
: during the repair. could be great stuff for insulating a forge.
Don't think it will work well - it is an ablative material - removes heat
be vaporizing - not really an 'insulatior'. But it does do that as well.
I think its a laminate - but at something like $300+ a square foot - how
much can you afford?
Shuttle tiles are not ablative.
The tile material has the property of disapating heat nearly as quickly
as its heated. You could touch it within seconds of heat removal.
And yes it is very fragile, maybe more so than regular fire brick.
Just thought you'd like to know.
No it doesn't (got a ref?)
I know nothing about space shuttle tiles, but I do know that the tiles
_can't_ do this, from the sheer physics of the problem. They're not
conductive (that's rather why they're there) and they can't radiate heat
more efficiently then some pretty fundamental limits.
AFAIR, the white tiles were so problematic to develop that it would have
been cheaper to simply insulate the shuttle all over with the "extreme
conditions" black carbon tiles. These were an established technology
(ICBM re-entry vehicles) and were pretty much problem free.
As an insulator, the Shuttle's tiles are well obsolete anyway. Aerogels
(which post-date the Shuttle) are vastly more efficient as insulators
and lightweight too. The state of the art (accoridng to European design
studies) is an aerogel blanket as insulator, coated with a thin layer of
a carbon compound (mesophase pitch, more ICBM spin-off) as a hard
I'd have to agree with Andy, being of a vintage where the NASA public
relations types visited our high school with samples long before the
shuttle flew the first time (since they were the hot new thing, and they
wanted to impress us future taxpayers, AFAICT). I recall that the tiles
were nicely insulative (demonstrated by heating one side with a torch
while the other side was hand held), but the red-hot spot from the torch
took some time to become non-incandescent, much less cool. Less
impressive now that I've done the same thing with lightweight fire
brick, but presumably a bit more durable than lightweight fire brick is.
And this is indeed not the foam that would have had CFCs in it.
The original foam that worked very well was replaced during the Clinton
administration with a non Freon type of "environmentaly friendly" foam
that does not stick at all well. What's more important people's
lives or some tree huggers concerns over environmental theory.
The tree huggers of course. Those particular tree-huggers are NASA
themselves (and others) flying their U2R under the polar ozone holes and
finding how much damage there already is. Secondly you're very confused
over the four types of "tile" used as insulation on the shuttle and the
fuel tank, and which one used CFCs.
China lost another couple of hundred coal miners today. Now obviously we
regret the Shuttle deaths, but some sense of proportion please. We've
lost fewer people exploring space than Columbus lost to scurvy on one
You have me mixed up with someone else. I made no mention at all of
tiles just the crappy foam that killed a whole crew and cost us 20% of
the original shuttle fleet. That added to the o-ring fubar which cost
another 20% of the fleet. We can't afford any more shuttle losses as
the whole space station project depends on them with no backup at all.
Just because China has no regard for human life does not mean we should
emulate them. The small amount of Freon in the original foam offered
next to zero effect on the atmospheric ozone
layer. The whole ozone hole problem has yet to be proved anyway. The
ozone layer has waxed and wained for many thousands of years.
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