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Fewer Heat Shield Dings on Shuttle Discovery
According to NASA, the amount of damage to thermal tiles noted on Discovery was significantly lower after the latest mission. According to the report, there was a 33% reduction in the number of dings on the belly of the orbiter and an almost 50% reduction in the number of hits greater than one inch. This would seem to indicate that the new foam is working better. "The vehicle looked very good," Thomas Ford, a member of NASA's ice-debris inspection team at Kennedy Space Center, said Wednesday. "It's definitely gratifying."
Wouldn't that be great. I really like this new administrator.
How we know is more important than what we know.
... the bleeps, the creeps, and the sweeps?
AccountKiller
Yeah, it's true, statistically women put a lot more dings in the vehicle than guys, but I'm afraid the guys blow them up a lot more.
.is twelve inches.
And it's a cheap shot against women to make fun of them for it. Their notorious inability to judge distances is all the fault of the guys in the first place.
They keep telling them that this:
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KFG
Better foam, less ding! Coming to you at your local Starbucks!
"amazing"? NASA was promising this level of launches over 20 years ago.
Engineering is the art of compromise.
...blah blah blah this new stuff works great...
I paraphrased a little there, but the REAL test of this stuff would be to park the shuttle in Walmart's parking lot for a few hours. See how it looks after that.
"What do you despise? By this are you truly known." --Princess Irulan, Manual of Muad'Dib
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Where's the data on all flights prior to that one? What are the maxima/minima and standard deviation? A 33 or 50% variation might be expected.
"National Security is the chief cause of national insecurity." - Celine's First Law
Can we please have a report on the landing wheelie thingos? I think there was a ding on one of the balancy thingamajigs.
The heat shields are shaped so the hot regions of the gas are kept away from the shield.
The problem isn't the heat, but the pressure (that causes this heat as a side effect).
During re-entry, the shuttle travels supersonic thereby preventing the air to get out of the way fast enough.
Thinking of fixing, there was a famous incident in WW2 where a supposedly ruined American aircraft carrier was repaired to battle-worthiness in three days. Its presence in a subsequent engagement created enough confusion among the Japanese commanders to cost them the battle. And you know, America really did once have a reputation for precisely this kind of engineering awesomeness, which helped build America into the industrial giant it is. Could America ever regain this prestige? Maybe... if they'd ditch their hero worship of illiterate business school and start celebrating their genius Scientists and Engineers again, if they tried to be the kind of Country that Einstein immigrated to, rather than the kind of country he emigrated from, if the very idea of someone having a degree other than an MBA didn't make the average American vomit with an intense anti-illectualist rage.
This was never a problem until NASA had to change to a non-freon coolant in the 90s, in order to comply with EPA regulations. Can't NASA get an exemption from this? Is freon that so bad that we can't even afford to allow the Shuttle to use it, at the expense of a kludgy workaround that has, to date, claimed 7 lives?
Tcl my Pico! There are 10 kinds of people in the world: Those who understand binary, and those who don't.
Actually, a female astronaut commanded the Return to Flight expedition, also aboard Discovery, which was also a very "clean" flight in terms of the tile damage.
Agreed. And in 1985, they had 9 launches in 12 months. Then they had the Challenger Accident and shut things down from about mid 1986 to late 1988. From 1989-2002, they averaged a little over one every two months. Then they had the Columbia Accident that shut things down from early 2003 to mid 2005.
So I'd say that, barring accidents, NASA has managed to launch one every two months.
No, China is known for sharing information with allies.
Companies from the United States are not well known for sharing their technology. .
In fact, the United States is known to be susceptible to private interests affecting their "foreign policy".
No offense, but every Country in the world deserves to be on equal footing. Military might be damned, and don't be surprised if you see some "competition" as a result.
This would seem to indicate that the new foam is working better.
The foam itself hasn't changed at all, so that comment is misleading. What's been changed is where the foam is applied.
Oh, and there's two types of foam btw. There's the stuff that gets sprayed on the acreage areas of the tank (which is applied by machine), and there's the foam that's hand applied to stuff that needs a bit more precision. The acreage foam is the new environmentally friendly stuff you hear blamed for the Columbia accident. Which is ironic, because it's the other foam, the hand applied variety, they've had so much trouble with. And guess what? It's the older, non "evironment friendly" type, and it's also the type that caused Columbia's disaster.
Mix the failings of Usenet with the shortcomings of the World Wide Web and the result is slashdot.
I still don't see why they can't put like a protective liner or coating on top of the fragile graphite/ceramic tiles to protect it.
I can think of one amazingly obvious reason why they don't do it: weight (or, more precisely, mass). Every pound of stuff you put on the tiles to protect them is a pound less the shuttle can carry into orbit. It already can't carry very much (compared to unmanned rockets that are far less expensive to operate), so slapping a few hundred (or perhaps thousand) pounds of stuff on the tiles to protect them is not going to work.
Now perhaps you'll say that such a coating wouldn't have to weigh much because it could be thin. I will remind you that the foam that brought down Columbia slammed into the wing at about 550mph relative to the shuttle's speed. Any coating that's going to do any good would have to be able to withstand such an impact or it's not worth the weight of the coating. I think you should now realize that any protective coating would have to be (a) very thick and (b) very heavy in order to do any good, which would therefore (c) make the shuttle's cargo-carrying capacity more pathetic than it already is.
It's a bad design. You can keep applying band-aids all you want, but having the heat tiles exposed to debris damage during ascent is a fundamentally bad design than can't readily be corrected. Ever see a Saturn V launch? Tons of ice shed from the ascent stages, crashing all over the place, yet no Apollo mission was ever in any danger whatsoever because of it. The "valuable" part of the stack was at the top, away from debris, and the heat shield itself was tucked away inside the stack. Until we come up with a way to launch things without cryogenic propellants, this is going to be the preferred arrangement for getting stuff into space.
In the end they will lay their freedom at our feet and say to us, Make us your slaves, but feed us. - Fyodor Dostoyevsky