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NASA Finds 4-5" Crack in Shuttle Insulation
PresidentKang writes "Spaceflight Now is reporting that a large crack has been found in an external tank foam of Space Shuttle Discovery on the launch pad. According to the article: "Engineers inspecting the shuttle Discovery's external tank following Sunday's launch scrub found a crack in the tank's foam insulation near a bracket holding a 17-inch oxygen feed line in place. Some engineers believe the crack must be repaired but senior managers say a variety of options are on the table, from fly as is to making repairs.""
"...but senior managers say a variety of options are on the table, from fly as is to making repairs."
I wonder what those managers would say if they had to fly the shuttle.
Meta will eat itself
Did they get posession charges or was there enough crack that they got booked for traffiking?
So now the real question becomes, which will launch first, DNF, Windows Vista, or the Shuttle? I say the Shuttle, it's cracks aren't nearly as big as Vista's (an M$ product) will be.
Look at the 'Latest' news on the right
Surely they should just get the thing working before they add extra features like that?
If we can put a man on the moon, why can't we shoot people for Apollo-related non-sequiturs?
I know the shuttle is at the end of life, but the follow on will still need insulated tanks. The early Atlas had no insulation and needed to be fueled in the final minutes of the countdown. Clearly a problem. But any means of making the insulation crack free, thus flexable, and still able to withstand the launch, thus stiff, would require significent added mass. Mayby an outer shell of carbon composite.
Not an engineering project or a business enterprise.
This type of thing is to be expected in political endeavors. Their purpose is never to satisfy the stated goals but to advance constituencies political agendas. For a political project failure is not only an option but often the most desirable one.
Fix it later? Aren't they running out of time before the July 4th launch? Wrap it in duct tape... that seems to work well for other insulated pipes installed at public institutions (at least from my observations).
Does anybody at NASA have a working memory? Don't they remember the results of the Challenger inquest, wherein plenty of evidence of engineers saying "DON'T LAUNCH! BAAAAD!" was ignored?
I fear we may very well get a "fourth to remember", and NOT in a good way! It is all very well for a bottlerocket to explode in flight, NOT A MANNED SHIP!
I fear that NASA is going to launch, come hell or high water, and damned be the consequences.
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You need to read better.
Last thing we need is a bunch of engineers going crazy on crack. Next time use the nose powder instead.
:)
mod +1 funny -5 not_funny -5 asshole_poster
If you can't take a little bloody nose, maybe its time to go home and crawl back under your bed. It's not safe out here. The galaxy is wonderous -- with treasures to satiate desires both subtle and gross -- but it's not for the timid..."
-Q, "Q Who?"
On the one hand, shuttles flew forever shedding foam and it only became a real problem when a large enough piece tore off to actually damage the shuttle in flight significantly. Engineers accepted the risks with many reservations, because damage was never really that severe. Of course hindsight is 20-20 and this problem could have been rectified if the foam was located interior to the tank as opposed to externally. I think they were worried that if they tried that, there would be voids in the insulation that would allow heat to enter and cause problems, but that was a manufacturing issue which probably could have been resolved with a little ingenuity.
On the other hand, a 4-5 inch crack is nothing to sneeze at and with the aerodynamic forces that batter a shuttle on its way into LEO, any number of things could cause that crack to widen and eventually spilt, teraing off a really large section of foam. It has to be repaired; I don't see how NASA management can ignore this. If they do, and the shuttle is damaged or heaven forbid, destroyed, that's the end of the space program. And probably rightly so. Like to many things, NASA was created due to Cold War concerns, namely that the Russians were going to grab the "high ground" of space and show us up in technical endeavors, weakening our position on the world stage. Like other Cold War relics, it too either needs to change or be dismantled.
I'm a NASA booster (forgive the pun) -- my dream from childhood was to walk on the Moon. But I can say that I find it hard to trust the NASA I see now; it has become hamstrung by indecision, beaureaucracy, and lack of imaginative leadership (with apologies to Dan Goldin, Sean O'Keffe, and Mike Griffin). I wanted John Young to become NASA Administrator -- tough talking, smart, no-nonsense, and imaginative. He might have (and still could if he wanted the job) lit a fire under NASA and got them thinking straight. The problem is, NASA was not prepared for life after Apollo and it shows. The STS was a compromise (no engineer in the early 70's thought solid rocket boosters were a good idea) and a poor one at that.
I think a) NASA needs to be saved from itself and b) the American people have to learn what a truly great resource they have in their space program. Barring either of those, it will be up to private industry to carry the torch.
GetOuttaMySpace - The Anti-Social Network
Well they've fueled the Shuttle twice already, Tuesday will be the third. Thermal stress was indicted as a contributing factor in foam detaching. Everything probably would have been fine if they had launched the first time, I suspect their cloud distance tolerances are too tight these days compared to thermal stress from fuel cycling on the parts for later lift off.
I'm not saying NASA should have launched the first time, but with only a 30% chance of launch due to weather, why did they even fuel the bird up? Weather should have a least an 80% chance window I would think think to decrease the likelihood of one fueled up scrub after another leading to excessive thermal stress on tank components.
Also while many may see July 4th as a feel-good day to launch (National pride and all that) if anything goes wrong there are religious types both Christian and Muslim that will see it as a sign validating whatever their view of the world is.
Letter To Iran
Been there since birth, I see no reason to patch it ;-)
the foam has always been the problem on the shuttle.
scrape it all off and keep the tank pressurized like in the old days for the remaining flights.
if this is supposed to be a new economy, how come they still want my old fashioned money?
Somehow I doubt that engineers were inspecting the tank. Why is it that every man with a hardhat, shovel or a wrench is an engineer in the eyes of the public?
since when has the 4th been a religious holiday?
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What?!?
Where in the heck are you getting that idea from? Bigotry? Bias? What the heck are you talking about? If you are trying to say that Christians or Muslims might claim it was punishment from God, for whatever weird reason you or they could come up with, then why link it to July 4th? If you are claiming July 4th holds some sort of numerological significance in either Christian or Muslim ideology, state your claim and back it up with at least a good conspiracy theory. If you are talking out of your @$$, as seems most likely, calm down and stop hating on people who think differently than you (isn't that what you want Christians and Muslims to do).
Not every Christian is a Pat-Robertson-Is-My-Prophet-Fundamentalist nor is every Muslim a radical terrorist; if you want to speak about a specific cult, point your bigoted finger at them specifically and not at the Christian and Muslim population in general.
When I was studying at Fermilab, Osheroff [link to:http://en.wikipedia.org/wiki/Douglas_D._Osherof f] gave a lecture about the Space Shuttle Columbia. He was selected to head up the review panel, and I'm pretty sure that I remember hearing that the foam was almost certainly the cause of the explosion.
Seems like an unwise decision to let it run without repairing it even if it is unlikely that anything will happen, no?
Mission control: "Astronaut this is mission contol. We have a problem. Over."
Astronaut: "Mission control this is Astronaut. What is the problem. Over."
Mission control: "Astronaut we're looking at the live biosigns from your transmitter and have come across a concern. Did your mother drop you as a child? Over."
Astronaut: "I don't believe so. Why? Over."
Mission control: "Because..."
*general snickering from mission control*
Mission control: "Because there's a big crack in your butt! Over and out."
I'll be your candy shop of infinite deliciousity if you'll be my discotheque of endless rump-shaking.
Give it a rest.
Take a look at "What Do You Care What Other People Think" by Richard Feynman and read what he had to say about the first shuttle disaster. NASA has had problems facing reality long before PowerPoint was available.
Wellll....
..but that isn't the connection he was going for I think. The connection would be God giving the Americans a bloody nose on the day that is their nation's pride day. The significance of it wouldn't be the religious properties of the day, but the secular one.
7 is heavenly perfection, and July is the 7th month.
4 is earthly perfection, and it's the 4th day.
NASA commited itself to solving the foam problem but when it turned out to be difficult they decided they didn't have to solve it. So they found evidence that the problem wasn't solved. How could this be in any way surprising?
Because in Florida (I live here) it doesn't matter what the weather report says, there's always a 50% chance of rain. I gave up listening to the weather reports long ago.
The only time they are right is when they say 'It's raining right now' or 'It's sunny outside.' We don't even need dark clouds for rain, lightning, or both. Sunny showers are not that uncommon.
In short, 30% is just as good as 80% here.
Oh, and btw, if the weather report says 'in 12 hours, a hurricane will hit your town' you can safely sit at home and eat popcorn. It's not going to hit you.
"If you make people think they're thinking, they'll love you; But if you really make them think, they'll hate you." - DM
I remember some anecdote about Gandhi. Someone asked him how come his stance on something is now the exact opposite of what it was last week. Gandhi said something like, "because this week I know better."
Now I'm no Gandhi, but I can think of a lot of situations when learning something new made me reverse my stance on something. In fact, I consider it to be what every sane human does all the time. Only zealots have one absolute truth and stick to it for ever, no matter what. A scientist (either theoretical or engineer) should have no such things by definition. If you learn some new fact, or do another calculation, or run another simulation, or whatever, and it contradicts what you previously believed, yes, as an engineer I'd _expect_ you to be ready and willing to change your mind about it. Maybe you'll run some extra tests, do more calculations or whatever first, that's ok, but you shouldn't ever have the last week's stance as something set in stone and unchangeable for any reason.
So, well, I won't argue a your point B for lack of enough data, but point A leaves me scratching my head in disbelief. So someone decided that those engineers aren't trustworthy... because they changed their mind? Seems like a pretty weird attitude. I definitely expected that at NASA even management would be a bit more open-minded than that. They're pretty much one continuous experiment and using experimental equipment, so it's exactly the kind of thing that should be _expected_.
We're not talking stuff like designing a bike, where you can just do it all by the book and know the same today as you knew last week. We're talking crazy experimental stuff that noone else has done before, and a lot of it is tried for the first time. Someone calculated that this valve should be perfectly safe, or that foam can't break this time, but essentially it's the first time anyone actually put that valve or that new foam on a rocket and blast it into space. There's a lot of stuff that could act differently than in the simulation, or than in whatever lab tests were done.
So, yes, stuff like someone doing some new calculations and deciding, "teh oops, this thing is gonna blow up" are the kind of thing I'd _expect_.
A polar bear is a cartesian bear after a coordinate transform.
Here are the slides and video from the talk. It was one of the good ones.
http://blogs.orlandosentinel.com/news_space_thewri testuff/2006/07/foam_falls_from.html
The problem with religious fanatics (and anyone who takes Revelations seriously is a fanatic), is that they will use any evidence as a validation of their delusions. It would be pointless to worry about such people.
Just last night there was a program broadcast on DayStar (a christian tv station) in which a preacher and his obviously strung-out-on-drugs assistant were showing clippings from newspapers, then reading passages from the bible, and crying with joy as they showed this proof that "the rapture" is near.
And yes, I watch that station because it makes me laugh more than comedy central. Good stuff.
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If they fly upside down, they'll have crack up
Use your head, can't you, use your head,
You're on earth, there's no cure for that - S. Beckett
GP makes sense, but is not right. Note: I'm not an authority on the Shuttle program by any means, but this is just basic science. What I'm saying below is even more true for the hydrogen, but I used the oxygen as an example. There are two basic reasons it would be quite cold.
1. To make Liquid Oxygen at room temperature does require extremely low temperatures. But they aren't keeping it THAT cold, because it would be prohibitively difficult.
It doesn't need to be that cold, because under pressure the temperature where it stays liquid goes up. You can keep a strong tank of O at room temperature and it will still be liquid. So they likely keep it cold to reduce the pressures they have to maintain somewhat, but it's not required.
2. Whenever you reduce the pressure on a gas (or especially when a liquid becomes a gas) this is a very endothermic (heat absorbing) process. So a home oxygen tank IN USE is cold, but one being stored isn't. (Random metal at room temp will FEEL cold, but the tank isn't _especially_ cold)
When you pour the liquid oxygen into a large temperature tank - even if you do it really fast and in a sealed way - any room left in the tank instantly becomes filled with much higher-pressure gaseous Oxygen. This expansion makes it very cold. And there is a lot of room in the tank when you START filling, even if by the end you filled it all.
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No one said it was
The revolution will not be televised... but it will have a page on Wikipedia
It's not that the 4th has anything to do with religion, but crazy Christians and crazy Muslims are the ones most likely to draw asinine conclusions from coincidences, especially coincidences that appear to show that the world and/or the USA is headed towards apocalypse or some other lesser downfall. I'm sure there is a handful of crazy Wiccans and crazy Hindus who believe the same kinds of things, but they are much less numerous and much less vocal. Islam and Christianity are by far the top 2 religions in the world by number of practitioners, and they are also have by far the greatest number of fundementalists. The practitioners of most other religions are on average far more liberal, rational, and tolerant (with a few notable exceptions like Hindu's caste system.)
Btw, "there are religious types both Christian and Muslim" doesn't mean "every single Christian and Muslim." If anyone is biased, it's you for not realizing that the vast majority of the world's moral/prophetic bullshit comes from these two religions.
Why not just wrap the entire outside of the foam with an overlapping spiral wrap layer of Duct Tape? You know it would hold it all together just fine, and that much duct tape would not really be weight-prohibitive either.
"then why link it to July 4th?"
Why did religious nuts pick the world trade towers? Because they're symbols of america... and err, july 4th has a kinda symbolic attachment to "the american way" too, which is something many people, religious and otherwise, have a problem with. However, someone who believes that god plans/controls/whatevers everything, is a lot more likely to believe that it's a message, than someone who is more enlightened.
The revolution will not be televised... but it will have a page on Wikipedia
"Oh, and btw, if the weather report says 'in 12 hours, a hurricane will hit your town' you can safely sit at home and eat popcorn. It's not going to hit you"
Unless they also say "the levvies will hold", in which case, you know you're in trouble
The revolution will not be televised... but it will have a page on Wikipedia
Duct tape has problems with the adhesive melting when it's applied to ducts. The adhesive weakens under the large amounts of heat in the ducts. Because of that, California has recently banned the use of duct tape on ducts. Imagine that on the space shuttle...
"it's not about aptitude, it's the way you're viewed" - Galinda
Also while many may see July 4th as a feel-good day to launch (National pride and all that) if anything goes wrong there are religious types both Christian and Muslim that will see it as a sign validating whatever their view of the world is.
:-)
I'd be willing to bet there are non-religious types, as well as religious types not Christian or Muslim, who will see it as a sign validating whatever their view of the world is too.
You're an idiot.
$x='S24;r)>63/* h@<5+oZ)32"5cz';$me='phroggy'x$];
$x=~y+ -xz+\0-Tx+;print$_^chop$me for split'',$x;
Either way, the STS needs to go. It's 30-year-old technology, is not truly reusable, and can't do anything at all out of LEO.
We can do far, far better. End the Shuttle program, put the orbiters into museums, and put its operating budget into R&D for a new spacecraft.
+++ATH0
Guilty. My fault.
If anyone is biased, it's you for not realizing that the vast majority of the world's moral/prophetic bullshit comes from these two religions.
Irrelevant. From whence "the vast majority of the world's moral/prophetic bullshit comes from" has no bearing on whether or not I am biased and no bearing on whether or not my statements regarding snubbing Christians and Muslims for their beliefs were correct or otherwise. What if I am biased, does it change what I said? What if I am not biased? Any change? None.
I never asserted "bias" on the part of the OP - I insinuated prejudice and stated bigotry. Personally, I believe we are all biased - invariably, we cannot help but see the world through eyes with lenses formed from varying experiences - and that that bias is *impossible* to completely overcome. That is where prudence and thoughtful reckoning must factor in.
Maybe this wasn't a strong enough disclaimer, but the there are religious types should indicate that I am not talking about ALL. Bigoted? Perhaps. I think my agnostic view of the world is superior to any of the World's organized religious. My common sense and experience having talked to religious people at work (and I'm talking a tech environment here) almost to a person they read great significance into random events. It seems to come part and parcel with the religious experience, especially those that interpret the Bible "literally."
You may consider it a cop out to take these factors into consideration. But it is possible to be scientifically rational and politically unwise. Why fuel any flames if you don't have to? Maybe it was unwise to fly the first Israeli astronaut, Ilan Ramon, to space on Columbia on the eve of war with Iraq. A HUGE percentage of the Islamic culture took Columbia's demise to be an act of God.
If we weren't at war I would say fine, don't bother avoiding a July 4th lift if reasonably possible. The most recent news is making it look like a July 4th liftoff is unlikely anyway. BUT it is always possible political pressure will be put the bear to have a July 4th launch for reasons of National pride. This is the kind of synchronicity of events that ends in tragedy.
If we should loose Discovery in launch it seems likely it will prolong certain aspects of our current military venture (whether you approve of that venture or not). The two shouldn't be connected, but they are because religious propagandists will make them connected. We should be surprised if our opponents in this clash of cultures would use NASA failures for propaganda purposes, the whole NASA manned space program is largely pro-American propaganda (when things go right).
Letter To Iran
After the difficulty NASA had with the Mars Orbiter back in 1999, and their subsequent determination to speed the transition to using SI units exclusively, it is amusing to see the problem described as a "4-5 inch crack", and the chunk that fell off as a "0.00057 pound, 3 inch piece". Wouldn't 0.25 g be clearer than 0.00057 lb? Exactly how long can transition take?
Enlightened, huh?
I'm not defending every belief of every religion out there but...the word "enlightened" is a word so full of superiority and dripping with disdain that I am surprised you would even choose to use it in a discussion like this. It is a word completely devoid of meaning in any debate that borders on philosophical because it can as easily be bandied about by either side. It is dismissive.
The Muslim, the Hindu, the Buddhist, the Christain can as easily dismiss an opinion on the same grounds: that you could never understand because you have not been "enlightened". You have not been blessed abundantly with understanding; you have not had your Eureka moment; etc. etc.
You might value science, observation and measurement, what it can offer - I see the allure and concur - but science is always in flux; we modify or tweak our facts over time as we learn more about the world around us. In other words, science does not yet have all the answers - and may never have all of the answers.
Some of those answers may not be knowable because we may have already dismissed some avenues of investigation...because they defy measurement and observation according to our current methodologies.
4 is earthly perfection, and it's the 4th day.
the significance of it wouldn't be the religious properties of the day, but the secular one.
{Clap! Clap!}
Nice. I see your point and I think it is valid (cf. the reactions of some Muslims to Hurricane "Private" Katrina and the reactions of some Christians to earthquakes in India and Pakistan). However, the original poster insinuated that there was a connection between the date - numerologically speaking - and any event that went bad on that day. The original parent post does not come across as even remotely interested in any connection between God and America; OP was snubbing his nose in disdain at Christians and Muslims because they are an easy target; he did not attempt, even humourously, to support why either Christians or Muslims would believe what he claimed and, instead, blasted a stereotype.
If God chose to punish America or any other place, the day would not matter; if you insinuate that the day does matter, you need to offer a bit more. If you are poking your fingers derisively at some other group, be they Christian, Muslim, Gays, Minorities, etc., even in jest, reconsider posting.
I'm done; I feel like I'm defending groups that, in many ways, I vehemently disagree with. However,
been trying to observe the launch all week. this sucks. i had packed and was about to make the four hour drive to houston to catch my plane. ten minutes ago i decided to cancel my flight to florida. i tried it on thursday too. it's way too much driving and flying and waiting to keep getting disapointed. my buds in orlando got it easy, they just have to deal with all the traffic everytime it gets scrubbed.
oh well. the Columbia shook me out of bed three years ago, and it rained pieces of astronauts all over my area, so i understand the precautions. i'd rather be denied the chance to see it launch than cry.
i disable sigs
My guess is that the cloud tolerances are strictly "too tight" in order to maintain a positive visual on the shuttle as it makes it's way into orbit. My guess is that the reasoning of this is that if the shuttle goes behind a cloud even for half of a second, that is long enough to have a piece of foam damage the orbiter and not get noticed by NASA's telescopic/high speed chase cameras.
While I agree that the "cloud factor" might be a bit too constricting, I think they want the ability to keep a very close eye on the bird during launch. Also, lightning is prevalent in Florida and can strike miles away from clouds, I don't know what kind of static wicks/lightning protection system the STS has. That could be another reason to have a low cloud tolerance.
Libertas in infinitum
Space Oddity
David Bowie
Words and music by David Bowie
Ground Control to Major Tom
Ground Control to Major Tom
Take your protein pills and put your helmet on
Ground Control to Major Tom
Commencing countdown, engines on
Check ignition and may God's love be with you
(spoken)
Ten, Nine, Eight, Seven, Six, Five, Four, Three, Two, One, Liftoff
This is Ground Control to Major Tom
You've really made the grade
And the papers want to know whose shirts you wear
Now it's time to leave the capsule if you dare
"This is Major Tom to Ground Control
I'm stepping through the door
And I'm floating in a most peculiar way
And the stars look very different today
For here
Am I sitting in a tin can
Far above the world
Planet Earth is blue
And there's nothing I can do
Though I'm past one hundred thousand miles
I'm feeling very still
And I think my spaceship knows which way to go
Tell my wife I love her very much she knows"
Ground Control to Major Tom
Your circuit's dead, there's something wrong
Can you hear me, Major Tom?
Can you hear me, Major Tom?
Can you hear me, Major Tom?
Can you....
"Here am I floating round my tin can
Far above the Moon
Planet Earth is blue
And there's nothing I can do."
Tsukasa: All I really want, is to be left alone...
First I heard they found 20 kilos of it in Oprah's pants. Now they are smuggling it on the Space Shuttle! What lengths will these drug runners go to?
Oh, *a* crack. Well, that's not quite as astonishing. But still a very serious matter indeed!
AHA! But 6 is IMPERFECTION! So..it's about bringing earthly perfection to sinners!!!
:D
You can string a connection between anything if you want to go silly enough
The usage of the word was a blatent troll in the spirit of it's parent posts ignorance... me using the word was pretty childish, I just felt like being childish. The parent post inspired me that way.
The revolution will not be televised... but it will have a page on Wikipedia
This is how CBS was reporting it (they like to make up their own stories ... add/remove key words) ...
... Crack in Shuttle ...
... What's the street value of crack nowadays anyway? And will the astronauts be prosecuted?
NASA Finds
My first thoughts
I'm sure if I googled enough I could find this answer but haven't run into one so far so here is my question...
WHAT do they use to protect their vehicle from heat? Why aren't we working with them or sharing that info.
Have they had these same problems?
"Never try to teach a pig to sing. It simply wastes your time and truely annoys the pig"
You evil SOB, how can you laugh at these poor fools ;). I get my belly laughs from FOX these days I must admit.
... Standards and Practices !
PenGun
Do What Now ???
Is it just me, or does it seem like the simplest solution to all these foam problems is to put the foam on the INSIDE of the tank. duh!
*3 hours after takeoff*
It's getting cold up here.
I agree. So many in the middle east WANT something bad to happen to America, so if the shuttle goes down, they'll naturally take it as Allah's curse on America. Especially since that region of the world is far more religious than we are. Thinking that God is on your side helps you fight longer and harder.
Reality has been a bit short of that mark. Sure, airlines have delays but nothing quite like space shuttles (the shuttles don't fly for years at a time and probably 90% or so of flights get delayed). Sure, planes crash but if they crashed as often as space shuttles, there'd be about 50 crashes at LAX before breakfast each morning.
Engineering is the art of compromise.
Sorry to piggyback on a joke. This is the actual status, copied from NASA's shuttle page
It sounds like "crack" isn't a very descriptive term. A small piece broke off, probably due to the weather-related causes. They're trying to decide if they need to erect a platform to do a hands-on inspection.
On the source page there's a picture that took me a minute to figure out, so I'll explain it. The solid orange to the left is the main body of the external tank. The round orange vertical item in the center of the picture is the LOX feed line. The big metal piece is probably part of the tripod mount. Just below and to the right of the mount is one of the brackets that holds the LOX line in place, covered in foam. Looking closely, you can see a little triangle of white where the little chunk (about 4 long) of foam spalled off. I assume the T-shaped feature to the right of that is the so-called ice/frost ramp, which they're concerned may be at risk for falling off in flight. It's much clearer in the high res picture linked on that page.
At first glance, it doesn't look like a concern at all, but obviously NASA wants to make sure of that. If anybody has serious reservations, they'll setup a platform to get somebody who knows what to look for up close to it and look for evidence that this may increase chances that the ice/frost ramp or other pieces of foam may fall (smaller cracks, loosening of the frost ramp, etc).
For comparison, this piece of foam is estimated at 0.0057 pounds and may be as large as a cellphone. The piece that struck Columbia's wing weighed an estimated 1.67 pounds and was described as "briefcase-sized"
(Also, the joke is 2nd Tuesday of next week. Your rendition makes about as much sense as a screen door on a battleship)Soyuz has an ablative heat shield. It's probably made of some sort of ceramic, formed into 8 layers called "blankets" (I think they're only flexible enough to allow for expansion and contraction of the spacecraft, not like a quilt). The capsule is single use, so the heat shield only needs to survive one re-entry, and the exposed surface area is small, reducing overall weight. The ablation (burning away of small particles) carries heat away from the capsule. A similar system has been used on pretty much every entry system except for the shuttles, even the Mars rovers. The Russians did use a system nearly identical to the space shuttles for their Buran shuttle, which was abandoned after one flight due to budget problems.
The weight and maintenance of an ablative heat shield were prohibitive in a very large reusable system like the shuttle. Instead, the leading wing edges and nose of the shuttle are protected by reinforced carbon-carbon tiles, the underside by ceramic tiles that are in some ways similar to aerogel, and other sensitive areas by a heat resistant cloth. The carbon-carbon is the most effective and actually pretty strong, but about 6 times more dense than the other options. Read more.
In short, no the Russians haven't had fatal problems with their thermal protection, but it's not feasible for a vehicle like the shuttle.
Did you even read the original post? He said that he could see the point of launching on 4th of July because of the historical significance of the date to Americans. He then followed up by saying it could backfire in the case of a disaaster, because American Detractors, such as radical Islamic terrorist groups might see it as a sort of divine justice for the percieved wrongs America has perpetrated on them. It's a perfectly logical point, and if he didn't use the proper PC terms to describe it, it still came across loud and clear to anybody who wasn't looking for a nit to pick.
NASA - Need Another Seven Astronauts
I hope we don't see a three-peat!
What do you mean, the "good old days"? The Saturn S-II and S-IV/IVB LH2 tanks were insulated. The S-II, I beleive, had essentially the same system for insulation as the shuttle main tank, except that it was painted white. LH2 tanks *need* insulation; they are much much colder than liquid oxygen as used in the Atlas example above. Of course, the insulation could be in the inside.
Brett
Why not encase the tank in an outer shell so the insulation is inside? i.e like a thermos.
Hey, I'm all for taking risks - calculated risks, where I have done what I can to mitigate those risks to the best of my ability. But there is a big difference between "OK, we have an aircraft that will be operating at 100% design spec to get you into space. If we exceed that by more than 10% you are toast, but we calculate the actual requirements to be about 99% +/- 5%, so you are in good shape" and "Well, yes there is a big crack in the window, but a little duct tape and some Superglue should hold together, we think, maybe, if we are lucky. Bon Voyage!"
Yes, this "there must be no incidents, no loss of life, no injuries" mindset - what are we, Pierson's Puppeteers?
But when we have a KNOWN FAILURE MODE, one that has already claimed the lives of one shuttle crew, and a second shuttle is showing that same failure mode, and the mindset is "Well, we'll just send them to the ISS, rig the shuttle with a remote control, and if the tiles get cracked we'll bring the shuttle down on remote and bring the crew back on Russian ships" - that is not merely "taking a risk", that is "taking an insane, unneeded risk."
www.eFax.com are spammers
Hey, that guy that doesn't understand what the Overrated moderation means is back on Slashdot today. Rather than tell him RTFFAQ I'll be nice and spoon-feed him:
Overrated -- Sometimes you'll run into a comment which for whatever reason has been moderated out of proportion -- this probably means several moderators saw it at nearly the same time, thought it was Funny, Insightful etc, and their scores added together exaggerate its relative merit. (A knock-knock joke at +5, Funny) Such a comment is Overrated. It's not knocking the original poster to say so, but it's probably better to spend your mod points on comments which are deserving of being moderated up.
You see "Overrated" is a mod you use when others have given a comment too much credit. If nobody has modded the comment up, it can't be overrated. Get it?
You can still use Troll or something if you disagree with my comment. I just hate to have you embarrass yourself this way.
Some requirement to reduce fluorocarbons lead to a recent change the formula of the foam. This made a the foam more prone to break off.
So thank the bureaucrat's not the shuttle engineers. Perhaps after the falure the engineers should return to the old formula. Perhaps they did, that part was not reported it the time.