Science > Physics > The Shuttle's foam insulation, and another question
| Topic: |
Science > Physics |
| User: |
"AJW" |
| Date: |
05 Aug 2005 03:01:13 PM |
| Object: |
The Shuttle's foam insulation, and another question |
After a billion bucks of problem fixing, the shuttle's fuel tank is
still shedding foam.
So here's my first question. Why shouldn't the foam be such that it
all sheds off at launch? Why isn't it really low density, low strength
foam that comes off easily at low speed. It's already done its job,
isn't t is just additional weight at that point?
The second question is, why do we need a space program at this point?
Back in the 60s, there were defense concerns, that's less a threat now.
The shuttle is only a little less useless than the new sub Jimmy
Carter, in terms of the well being of most of us, although it does
provide a federal job program for lots of people who might not be able
to get employment in the private sector. What a resume: "Yeah, I was
program manager for the shuttle's fuel tank insulation. Program cost a
billion, didn't work too well."
Oh well.
.
|
|
| User: "Uncle Al" |
|
| Title: Re: The Shuttle's foam insulation, and another question |
05 Aug 2005 03:59:15 PM |
|
|
AJW wrote:
After a billion bucks of problem fixing, the shuttle's fuel tank is
still shedding foam.
Needs some fiber. Seriously.
So here's my first question. Why shouldn't the foam be such that it
all sheds off at launch? Why isn't it really low density, low strength
foam that comes off easily at low speed. It's already done its job,
isn't t is just additional weight at that point?
No. Why don't you calculate the volume of foam applied.
The second question is, why do we need a space program at this point?
Political favors must be repaid. Threats must be levied. Don't ever
question the porkbarrel.
Back in the 60s, there were defense concerns, that's less a threat now.
The shuttle is only a little less useless than the new sub Jimmy
Carter, in terms of the well being of most of us, although it does
provide a federal job program for lots of people who might not be able
to get employment in the private sector. What a resume: "Yeah, I was
program manager for the shuttle's fuel tank insulation. Program cost a
billion, didn't work too well."
http://www.mazepath.com/uncleal/
--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/qz.pdf
.
|
|
|
| User: "G=EMC^2 Glazier" |
|
| Title: Re: The Shuttle's foam insulation, and another question |
05 Aug 2005 05:51:48 PM |
|
|
Hi Uncle A Best to keep in mind NASA shuttle program is run by the
Calif. Mafia The less they spend on safety the more they can steal
CNN has 2 billion bucks not accounted for from last years budget. The
shuttles should have been scuttled after the first one built. Russia
copied our shuttle,and the one they built is in a Moscow park.They
claimed it was not fit to fly. Our NASA is constantly proving this.
Beert
.
|
|
|
|
|
| User: "Sam Wormley" |
|
| Title: Re: The Shuttle's foam insulation, and another question |
05 Aug 2005 03:27:10 PM |
|
|
AJW wrote:
After a billion bucks of problem fixing, the shuttle's fuel tank is
still shedding foam.
Was all the billion spent on the foam problem? If not how much
was spent on the foam problem?
So here's my first question. Why shouldn't the foam be such that it
all sheds off at launch? Why isn't it really low density, low strength
foam that comes off easily at low speed. It's already done its job,
isn't t is just additional weight at that point?
Do you know the purpose of the foam as the space craft passes
through the atmosphere, faster and faster and faster?
.
|
|
|
| User: "PD" |
|
| Title: Re: The Shuttle's foam insulation, and another question |
05 Aug 2005 04:56:50 PM |
|
|
Sam Wormley wrote:
AJW wrote:
After a billion bucks of problem fixing, the shuttle's fuel tank is
still shedding foam.
Was all the billion spent on the foam problem? If not how much
was spent on the foam problem?
So here's my first question. Why shouldn't the foam be such that it
all sheds off at launch? Why isn't it really low density, low strength
foam that comes off easily at low speed. It's already done its job,
isn't t is just additional weight at that point?
Do you know the purpose of the foam as the space craft passes
through the atmosphere, faster and faster and faster?
As far as I know, the purpose of the foam is to prevent icing on the
tank, which would of course would be a problem in humid, sunny Florida.
The ice would weigh more than the foam, and worse, it would be an
unpredictable weight.
The purpose of the foam is NOT ablation. Note that the Saturn V used
for the Apollo missions had no such foam.
It was noted that the piece of foam that fell off this time did not do
damage precisely because it fell off in higher, thinner atmosphere
where there was less atmospheric drag. Thicker atmosphere would have
meant larger drag and therefore larger relative acceleration of the
chunk as it passed by potential targets on the rest of the craft. What
this means to me is that a design that makes it all fall off low in the
atmosphere would be an unmitigated disaster, unless it fell off before
the rocket had achieved a speed of 30 mph or so (i.e. more or less
instantly). I would think that if it didn't fall off absolutely
symmetrically, the weight imbalance would likely cause another sort of
instant disaster.
Note that the foam is driven by choice of fuel. Burt Rutan and the
folks at Advanced Composites had much different ideas about that.
PD
.
|
|
|
| User: "tj Frazir" |
|
| Title: Re: The Shuttle's foam insulation, and another question |
05 Aug 2005 05:35:58 PM |
|
|
Nasa has fingers crossed ,,,
it wount have a problem , unless it blows the ***** up.
No one garentees it dont blow up.
It might blow up.
it might not.
But Nasa has its fingers crossed .
quick rply ,,***** nasa coulnt find thier asses with boath hands .
slicker sticker..
give to congress to give to nasa to give to contactor that give to
congress re-elect.
Nasa is a money laundering service.
and garbage truck
.
|
|
|
| User: "T Wake" |
|
| Title: Re: The Shuttle's foam insulation, and another question |
06 Aug 2005 07:03:25 AM |
|
|
"tj Frazir" <GravityPhysics@webtv.net> wrote in message
news:9188-42F3E9CE-77@storefull-3218.bay.webtv.net...
boring repetitive nonsense
Grow up fool.
.
|
|
|
|
| User: "night dalits" |
|
| Title: Re: The Shuttle's foam insulation, and another question |
05 Aug 2005 10:16:00 PM |
|
|
********PLONK***********
.
|
|
|
|
|
| User: "Sam Wormley" |
|
| Title: Re: The Shuttle's foam insulation, and another question |
05 Aug 2005 05:56:09 PM |
|
|
PD wrote:
Sam Wormley wrote:
AJW wrote:
After a billion bucks of problem fixing, the shuttle's fuel tank is
still shedding foam.
Was all the billion spent on the foam problem? If not how much
was spent on the foam problem?
So here's my first question. Why shouldn't the foam be such that it
all sheds off at launch? Why isn't it really low density, low strength
foam that comes off easily at low speed. It's already done its job,
isn't t is just additional weight at that point?
Do you know the purpose of the foam as the space craft passes
through the atmosphere, faster and faster and faster?
As far as I know, the purpose of the foam is to prevent icing on the
tank, which would of course would be a problem in humid, sunny Florida.
The ice would weigh more than the foam, and worse, it would be an
unpredictable weight.
The purpose of the foam is NOT ablation. Note that the Saturn V used
for the Apollo missions had no such foam.
It was noted that the piece of foam that fell off this time did not do
damage precisely because it fell off in higher, thinner atmosphere
where there was less atmospheric drag. Thicker atmosphere would have
meant larger drag and therefore larger relative acceleration of the
chunk as it passed by potential targets on the rest of the craft. What
this means to me is that a design that makes it all fall off low in the
atmosphere would be an unmitigated disaster, unless it fell off before
the rocket had achieved a speed of 30 mph or so (i.e. more or less
instantly). I would think that if it didn't fall off absolutely
symmetrically, the weight imbalance would likely cause another sort of
instant disaster.
Note that the foam is driven by choice of fuel. Burt Rutan and the
folks at Advanced Composites had much different ideas about that.
PD
As PD points out, the foam is used to insulate the tank before
and during the launch. The foam is used to keep the propellants
that fuel the Shuttle's three main engines at an optimum
temperature of minus 423° Fahrenheit for the liquid hydrogen
and minus 297° Fahrenheit for the liquid oxygen, whilst also
preventing the build-up of ice on the outside of the tank.
The foam also serves to protect the tank from temperatures as high
as 1,200° Fahrenheit generated by aerodynamic friction and rocket
exhaust during the launch. Finally, the foam serves to hold the
tank together, allowing it to safely disintegrate over the ocean
as it re-enters the earths atmosphere having been ejected from the
Space Shuttle approximately 30 minutes after take off.
.
|
|
|
| User: "Boris Mohar" |
|
| Title: Re: The Shuttle's foam insulation, and another question |
08 Aug 2005 08:27:40 AM |
|
|
On Fri, 05 Aug 2005 22:56:09 GMT, Sam Wormley <swormley1@mchsi.com> wrote:
PD wrote:
Sam Wormley wrote:
AJW wrote:
After a billion bucks of problem fixing, the shuttle's fuel tank is
still shedding foam.
Was all the billion spent on the foam problem? If not how much
was spent on the foam problem?
So here's my first question. Why shouldn't the foam be such that it
all sheds off at launch? Why isn't it really low density, low strength
foam that comes off easily at low speed. It's already done its job,
isn't t is just additional weight at that point?
Do you know the purpose of the foam as the space craft passes
through the atmosphere, faster and faster and faster?
As far as I know, the purpose of the foam is to prevent icing on the
tank, which would of course would be a problem in humid, sunny Florida.
The ice would weigh more than the foam, and worse, it would be an
unpredictable weight.
The purpose of the foam is NOT ablation. Note that the Saturn V used
for the Apollo missions had no such foam.
It was noted that the piece of foam that fell off this time did not do
damage precisely because it fell off in higher, thinner atmosphere
where there was less atmospheric drag. Thicker atmosphere would have
meant larger drag and therefore larger relative acceleration of the
chunk as it passed by potential targets on the rest of the craft. What
this means to me is that a design that makes it all fall off low in the
atmosphere would be an unmitigated disaster, unless it fell off before
the rocket had achieved a speed of 30 mph or so (i.e. more or less
instantly). I would think that if it didn't fall off absolutely
symmetrically, the weight imbalance would likely cause another sort of
instant disaster.
Note that the foam is driven by choice of fuel. Burt Rutan and the
folks at Advanced Composites had much different ideas about that.
PD
As PD points out, the foam is used to insulate the tank before
and during the launch. The foam is used to keep the propellants
that fuel the Shuttle's three main engines at an optimum
temperature of minus 423° Fahrenheit for the liquid hydrogen
and minus 297° Fahrenheit for the liquid oxygen, whilst also
preventing the build-up of ice on the outside of the tank.
The foam also serves to protect the tank from temperatures as high
as 1,200° Fahrenheit generated by aerodynamic friction and rocket
exhaust during the launch. Finally, the foam serves to hold the
tank together, allowing it to safely disintegrate over the ocean
as it re-enters the earths atmosphere having been ejected from the
Space Shuttle approximately 30 minutes after take off.
Why can't the foam be on the inside of the tanks?
Regards,
Boris Mohar
Got Knock? - see:
Viatrack Printed Circuit Designs (among other things) http://www.viatrack.ca
.
|
|
|
|
|
|
| User: "tj Frazir" |
|
| Title: Re: The Shuttle's foam insulation, and another question |
05 Aug 2005 05:38:51 PM |
|
|
it will cost 50 million to studdy and 5 million to haul the trash to the
fucking dump.
irac cost 1 billion per day .
.
|
|
|
| User: "T Wake" |
|
| Title: Re: The Shuttle's foam insulation, and another question |
06 Aug 2005 07:04:25 AM |
|
|
"tj Frazir" <GravityPhysics@webtv.net> wrote in message
news:9187-42F3EA7B-481@storefull-3218.bay.webtv.net...
it will cost 50 million to studdy and 5 million to haul the trash to the
fucking dump.
irac cost 1 billion per day .
Teaching you to spell obviously costs more than the whole world has. You
cant even use a spell checker you retard.
Buy a decent PC - they are as cheap as your TV now you moron.
.
|
|
|
| User: "Richard Tobin" |
|
| Title: Re: The Shuttle's foam insulation, and another question |
06 Aug 2005 04:14:22 PM |
|
|
In article <oPCdnT_PHfDEOmnfRVnyhQ@pipex.net>,
T Wake <taswakeAt@hotmail.com> wrote:
Teaching you to spell obviously costs more than the whole world has.
He doesn't need a spell checker, he spells like that on purpose.
In other contexts he spells perfectly normally: it's just a joke.
-- Richard
.
|
|
|
|
|
|
|
| User: "Andy Resnick" |
|
| Title: Re: The Shuttle's foam insulation, and another question |
08 Aug 2005 08:16:50 AM |
|
|
AJW wrote:
After a billion bucks of problem fixing, the shuttle's fuel tank is
still shedding foam.
The total return-to-flight expense was around $1B. Of that, the specific
issue of foam shedding cost around $250M, AFAIK. To be sure, NASA's
accounting system is way screwed up, making it hard to get specific
numbers that make sense.
So here's my first question. Why shouldn't the foam be such that it
all sheds off at launch? Why isn't it really low density, low strength
foam that comes off easily at low speed. It's already done its job,
isn't t is just additional weight at that point?
A better question: why not wrap the whole tank in chicken wire?
The second question is, why do we need a space program at this point?
<snip>
A fair question. Why do we need *any* federally-funded R&D program? Is
that a proper role for government? What is the proper role for
government? Different taxpayers have different answers.
--
Andrew Resnick, Ph.D.
Department of Physiology and Biophysics
Case Western Reserve University
.
|
|
|
| User: "Uncle Al" |
|
| Title: Re: The Shuttle's foam insulation, and another question |
08 Aug 2005 12:17:49 PM |
|
|
Andy Resnick wrote:
AJW wrote:
After a billion bucks of problem fixing, the shuttle's fuel tank is
still shedding foam.
The total return-to-flight expense was around $1B.
NASA publicly admits to $1.4 billion. We all know it was larger than
that, most of the excess being untraceable.
Of that, the specific
issue of foam shedding cost around $250M, AFAIK. To be sure, NASA's
accounting system is way screwed up, making it hard to get specific
numbers that make sense.
NOBODY spends a quarter $billion to diddle foam. What was their test
scale, 1000 yds^3 at a crack? Add some long fiber reinforcement to
prevent fracture shedding get on with it.
So here's my first question. Why shouldn't the foam be such that it
all sheds off at launch? Why isn't it really low density, low strength
foam that comes off easily at low speed. It's already done its job,
isn't t is just additional weight at that point?
A better question: why not wrap the whole tank in chicken wire?
Shows what you know about political porkbarrelling. A real politician
would demand Akzo M5 (Doetze Sikkema group leader) -
poly{2,6-diimidazo[4,5-b:4’,5’-E]pyridinylene-1,4-(2,5-dihydroxy)phenylene}
- and not the least because it is a beautiful blue color (nice for
Congressional hearing and Media sample giveaways).
http://www.nap.edu/execsumm_pdf/11268.pdf
http://www2.umist.ac.uk/material/research/raman/web-page/Raman_pubs/1999_5.pdf
Figure 15-25 years for testing and approval - with recommendations for
more testing for UNKNOWN HAZARDS.
The second question is, why do we need a space program at this point?
<snip>
A fair question. Why do we need *any* federally-funded R&D program? Is
that a proper role for government? What is the proper role for
government? Different taxpayers have different answers.
The proper roles of government are
1) enact loose rational limits for the common good;
2) to set and maintain standards for currency and measurement;
3) to sustain and enforce an unbiased and effective system of laws,
courts, and punishments;
2) to enable projects whose potential benefits reasonably justify
costs - but less so than industrial research;
3) to enforce personal responsibility rather than remove it.
When an effete and corrupt society realizes it can vote itself rich
out of the public exchequer, it is doomed by its own compassionate
hand.
--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/qz.pdf
.
|
|
|
| User: "Andy Resnick" |
|
| Title: Re: The Shuttle's foam insulation, and another question |
08 Aug 2005 02:50:11 PM |
|
|
Uncle Al wrote:
<snip>
The proper roles of government are
1) enact loose rational limits for the common good;
2) to set and maintain standards for currency and measurement;
3) to sustain and enforce an unbiased and effective system of laws,
courts, and punishments;
2) to enable projects whose potential benefits reasonably justify
costs - but less so than industrial research;
3) to enforce personal responsibility rather than remove it.
When an effete and corrupt society realizes it can vote itself rich
out of the public exchequer, it is doomed by its own compassionate
hand.
Unc, I know better than to take your bait- I'll simply state that my
personal belief regarding government is similar to yours. The sticky
point is your second (2) (presumably 4). Who decides? Thus, the rise of
special interest groups who lobby support for pet causes and projects.
The danger is that science becomes yet another special interest,
competing against smaller and smaller pools of discretionary funds.
The assigning of funds is directed by people who cater to semi-catatonic
drooling imbeciles, aka the voting public. Nobody ever won office by
being honest. Americans like having fat white pious men in charge. If
they didn't, we would not have fat white bible-banging males running the
country.
--
Andrew Resnick, Ph.D.
Department of Physiology and Biophysics
Case Western Reserve University
.
|
|
|
|
|
|
| User: "Scismgenie" |
|
| Title: Re: The Shuttle's foam insulation, and another question |
08 Aug 2005 09:09:07 AM |
|
|
The insulation also provides a smooth surface for air to slide over,
rducing drag. (My suggestion is to form fit it in a layer of Mylar, so
it stays ON, and is SMOOTHER.)
Jeff Scism,
whose resume includes being a Space Suit Technician
.
|
|
|
| User: "Scismgenie" |
|
| Title: Re: The Shuttle's foam insulation, and another question |
08 Aug 2005 09:20:44 AM |
|
|
The Foam needs substance and a exterior surface that resists spalling.
The reason it falls off is that high velocity air gets between it and
the tank itself, probably a result of the extreme temperatures,
expansion and contraction. My above suggestion of shrink wrapping the
tank will provide surface tension and contain any loose pieces in
place, just like taping the whole thing.If they want the foam to come
off at a certain point a electrically triggered det cord would do it.
(Probably already there to help the tank disintegrate after it is
detached.)
.
|
|
|
|
|
|
Related Articles |
|
|
