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Discovery's Dangling Gapfiller Removed by Hand
Cyclotron_Boy writes "According to the New Scientist and NASA TV, Discovery's gap-fillers were removed successfully by hand by astronaut Steve Robinson earlier today during the eva. They didn't even have to use the forceps or the makeshift hacksaw-blade tool."
...Good news everyone! You get to live!
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I, for one, think that the less makeshift hacksaws we are forced use on multi-billion-dollar equipment, the better.
I never spellcheck and I freely admit it. Save your karma for more worthwhile "lol erorrs" replies
They pulled on the dangly thing on the underside until a substance came out, and now there is no chance of overheating on reentry?
Hope no one takes that outta context...
Good quote, too many chars. Seriously, the slashdot 120 char limit sucks!
This whole thing reeks of "see, we can fix the shuttle in orbit so it wont a-splode anymore".
From what I understand, this type of thing is normal, and the filler stuff tends to peel out on every flight, and it's basically designed to that.
The whole thing just seems so staged. But if it keeps the shuttle from a-sploding, then good for them, I suppose.
I don't need no instructions to know how to rock!!!!
Transcript of conversation between Discovery and ground control:
Discovery: OK, Houston...I'm in position..I see the dangling gap-filler now.
Houston: OK, Discovery...just grasp the gap-filler and pull.
Discovery: OK, Houston...I'm pulling now...it's coming out...it's coming out rather easily.
Houston: Just keep pulling gently and firmly...you're doing well.
Discovery: It's still coming, Houston...there's a lot more here than I thought...
Houston: Say again, Discovery?
Discovery: I said there's quite a lot of gap-filler here...about twenty yards so far...
Houston: STOP PULLING, Discovery...it seems you're unravelling the whole belly of the ship!
Discovery: I'm what, Houston? Say again, ple...OH SHIT! THE GODDAMNED TILES ARE ALL FALLING OFF!
Houston: Don't panic, Discovery.
Discovery: DON'T PANIC, YOU ASSHOLE? WHAT SHOULD I DO? WE NEED THOSE TILES!
Houston: Stand by, Discovery...we're working on a solution.
Discovery: SCREW YOU, HOUSTON! We're going to the ISS now...send up another shuttle to carry our asses back home!
Houston: Um...yeah...about the other shuttles, Discovery...
Discovery: What NOW?
Houston: Yeah...the shuttle fleet has been permanently grounded...too many people freaked about the foam thing...
Discovery:Nobody up here CARES, Houston...you get us a flight outta here NOW, or we start smashing satellites!
Houston: OK, OK, Discovery...no need to get violent...I'll make some calls.
Discovery: Yeah...you do that...and just so you know we're serious...
Houston: What do you mean?
Discovery: When we hear some good news from you, you'll get CNN back. Not before.
____
~ |rip/\/\aster /\/\onkey
The idea was that this dangling material might focus heat onto those surrounding tiles like a blowtorch on re-entry. Intead of the heat being evenly distributed over the entire surface, that area might get super-hot and burn up the shuttle.
The fabric is to prevent the tiles from banging together on lift-off. From the gist of the article, it sounds like it doesn't matter for re-entry. I guess they'll find out the exciting way when they try to land.
/. ++
Everytime I approach my wife with my Dangling Gapfiller, she threatens to hacksaw it off!
I thank you!
"What's Bond doing?"
"I think he's attempting reentry, sir."
According to the article they are made of ceramic-coated fabric and serve as buffers so the tiles do not rattle together and get damaged. I would imagine that during liftoff the ride is a little bumpy. The article also says that the only reason they are doing this is they think that they may cause added heat due to friction during re-entry.
This was discussed in the previous article but the material is coated in a material that can withstand thousands of degrees of heat. It would not burn off. Even the smallest stray piece of material can cause disruption upon re-entry.
If your read the article to the end, you'll notice the passage that they put some material samples in a bag to see how they fare in open space environment. Well, let this to be told: one of these samples was a LIVE MOUSE !
... that's one very expensive mousetrap.
Hmmm
On a more serious note, I imagine they're running this experiment to prepare for the eventual necessity of resusitating a human after exposure to vacuum. We use animals in medical experiments, to test new food additives, and even to make sure our beauty products are safe for people.
So, unless you want to give up medical research, beauty products, and dozens of other things that we take for granted--and need to ascertain are safe before they come to market--get over it. They aren't tortuing animals for the thrill of it, they're doing important science designed to save human lives, and regardless of what propoganda may be coming out of the mouths of PETA zealots, human life is more valuable than animal life. That's why we eat the critters and wear their skins, after all (or have you never owned a pair of leather shoes?).
The Future of Human Evolution: Autonomy
The gap filler is needed to keep the tiles from rattling on LIFTOFF. Once in space, we don't need it.
The reentry has very different pressures/angles - I believe the pressure of the reentry keeps the tiles from moving enough to bump each other too badly.
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Since the tiles thermally expand or contract very little compared to the orbiter structure, it is necessary to leave gaps of 25 to 65 mils between them to prevent tile-to-tile contact. Nomex felt material insulation is required in the bottom of the gap between tiles. It is referred to as a filler bar.
There are currently 9 people on ISS, and except for the 2 assigned crewmen I don't believe any of them have the necessary seats for the Soyuz. So even if you wanted to use it only 1/3rd of the people could fit.
Fortunately protruding gap filler is a minor issue, because you just can't evacuate 9 people from ISS with the attached Soyuz.
I've got your dangling gap filler right here! *grabs crotch*
...
Good thing I have my forceps and makeshift hack-saw blade tool handy
Toronto-area transit rider? Rate your ride.
the sooner we are going to start moving again.
I'm sorry but way more people died travelling to california when america was being explored. We have become so risk averse it is paralyzing us.
It may just be that the best we can hope for is 1/50 blows up. Do we give up space so we can save a few lives when millions die without purpose everyday to allergic reactions, cancer, stupid accidents, animal attacks, religious stupidity, stupid stunts, hazing, beer chugging, etc?
I'm sure many astronauts would accept a higher risk if it meant they could fulfill their purpose and go into space. How terrible it must be to train for many years and then watch all your dreams disappear in a suspended program.
She was like chocolate when she drank... semi-sweet at first and then increasingly bitter.
You can bring a shuttle down under computer control.
You can go into final approach under computer contro.
But you can't land. No landing gear.
The only way to open the landing gear is with a manual control. AFAIK it's the *one* part of the shuttle with no connection to the computers. ISTR that they were afraid of a computer glitch deploying the landing gear prematurely - say on orbit. The landing gear can only be stowed by the ground crew. There is no "raise landing gear" switch on the shuttle. Actually, the landing gear mostly "fall" open by gravity - it's the act of unsealing the doors premature that would cause a Bad Day.
The living have better things to do than to continue hating the dead.
Normal debris and dust would certainly burn up, but this is a material that is specifically designed not to burn up on re-entry. AFAIU, the reason they want to get rid of it is that it might cause an increase in temperature because of the additional friction.
Reality is defined by the maddest person in the room
Clearly you're not a redneck, what you really need is duct tape and WD-40.
If it moves and shouldn't use the duct tape. If it doesn't move and should use the WD-40.
Plus if you have a lighter you can make some really cool pyrotechnic displays with only those tools.
I'm just finishing reading "Comm Check," a book on the Columbia accident by Michael Cabbage and William Harwood. I've read a lot about the shuttle ever since its first flight 24 years ago, and if there's one thing that's abundantly clear, it is this: the shuttle is a lemon.
What's so tragically funny here is that, in the book, a NASA rep is quoted as saying "the shuttle isn't a lemon" right after the CAIB report pretty much said NASA was flying a platform that was not only unreasonable unsafe, but also one having such serious design flaws as to be much less safe than necessary. Spaceflight may never be as safe as an airplane ride, but the level of risk associated with the shuttle is just much more than it could've been with a better design.
Disocover magazine had a lengthy article about twenty years ago on how the shuttle was developed, and it was an amazing insight into how so many compromises can add up to a vehicle that is not only hugely different than what was originally invented, but also one that just doesn't do anything really well. The cargo capacity was too small. It can't achieve high orbits. It lands as an unpowered glider with a glide ratio of a brick wall. It has solid boosters that can't be throttled, trimmed, or turned off. There is no practical escape or abort manuver during the most dangerous parts of the flight (launch & re-entry). Worst of all, it's designed in such a fashion that there are an amazing number of "criticality-1" items. If a crit-1 item fails, it will result in "loss of mission, crew, and vehicle." The shuttle system has several thousand crit-1 items. To the average I.T. geek, that's like running a few thousand servers, each holding billions of dollars worth of data, and not having any redundant hard drives, power supplies, or UPS's. In other words, madness.
There isn't a single solitary thing the shuttle does better than the Apollo-era capsules it was supposed to replace. Launch costs for the shuttle were supposed to be 1/10th those of the throwaway boosters, but instead they are more than ten times what the Saturn V cost in adjusted dollars.
So, to sum it up, the shuttle is more expensive, less reliable, less capable, and more dangerous than its predecessor. Yeah, gimme more of that.
The ISS is also a boondoggle for many of the same reasons. Why do we have a shuttle fleet? To build the space station, of course! Why are we building a space station? To give the shuttles somewhere to go, of course! It's a circular argument. No shuttle equals no station, and no station equals no shuttle. No wonder NASA has its head so far up its exhaust nozzles it can't see the shuttle is an amazing failure. To admit failure would be to kill off the two biggest projects the organization has.
As has been said elsewhere here, our technology is just not yet at the point where something like the shuttle is practical. We just don't have the propulsion and materials to do it just yet. What we should be doing instead is using the best practical technologies out there, namely BDB's (Big Dumb Boosters). The aren't sexy, but they work, and they can haul a cubic buttload of cargo into orbit -- or beyond.
Unfortunately, I have the sinking feeling NASA is going to have to kill another seven astronauts before they finally, regrettably put the shuttle to bed. It was a good try, but you have to be able to admit when you are wrong. Build us a modern version of the Saturn V. With modern materials and modern computers, it could be made more cheaply and even more reliable than before, probably with more lift capacity as well. Make it so it does one thing very well. We don't need a Swiss Army knife of a shuttle to get into space, not when you've got much better proven technologies that are already available. NASA can get this right. The big question is, will they?
In the end they will lay their freedom at our feet and say to us, Make us your slaves, but feed us. - Fyodor Dostoyevsky
Sure. Do you happen to have a formula for some spray-on stuff that will withstand the 3000F re-entry temperatures? Oh, and it has to be very light, at least as light as the current "gap filler," because if it's too heavy at all it will drastically hurt the shuttle's load-carrying capability (there are a lot of gaps to fill for the tens of thousands of tiles on the shuttle, of course). And it has to be cheap so it doesn't increase launch costs. And it has to be easy to apply so it doesn't increase turnaround times and costs. And it has to interact well with the existing tiles so it doesn't damage them or degrade their capability. And it has to be aerodynamically sound so nothing interrupts the smooth airflow under the belly.
Yeah, it's so simple, I just can't imagine why NASA hasn't come up with something like this.
In the end they will lay their freedom at our feet and say to us, Make us your slaves, but feed us. - Fyodor Dostoyevsky
Rather than using tiles wouldn't it be better to use some sort of spray adhesive
The tiles are heat radiators, not adhesives. Perhaps you meant the filler? It's not an adhesive either. There has to be gaps between the tiles (because the skin and tiles don't have the same thermal expansion coefficient), but gaps can pose problems (they increase the likelyhood of tiles falling out, for one; they also tend to channel in extra heat during reentry). The fillers deal with both of these issues.
What actually attaches the tiles to the skin isn't the filler, or even an adhesive - it is a felt strain isolation pad. A simple adhesive would come loose under thermal expansion. The tiles are attached to the pad, which is in turn attached to the skin.
"It felt almost as good as stealing cars from grandma." -- Margaret Thatcher, probably.
Technically, both Challenger and Columbia were not in space. Challenger was well within the atmosphere during liftoff, and Columbia was about 40 miles (about 65km) up, well below the 100km mark.
However, the Russians did have 3 deaths in space, on one of the Soyuz/Salyut missions (my apologies to any Russians, I don't remember the specific mission number). Komarov on Soyuz 1 was probably not an in-space death as well -- his chute tangled, and I believe he died on impact, which is definitely not an in-space death.
So out of 18 known in-flight deaths (and I am not counting Apollo 1, that wasn't in-flight), only three were in space.
General Relativity: Space-time tells matter where to go; Matter tells space-time what shape to be.
The Russians have the much cheaper and safer soyuz, not because they are especially smarter, but because they just cannot afford to run their shuttle.
The Russians understand something that NASA does not, namely that their technology is limited and thus must be overengineered for saftey. Everything about the former Soviet space program was overdesigned for a reason, just like our Saturn V was: to give good safety margins without going gonzo with costs. If you've got four engines making enough thrust to get you into orbit, you add a fifth for safety and then run all your engines at 80% rated thrust for even more safety. Is it efficient? No, but it's safer.
Now, I'm not about to argue that space exploration is, or ever should be, perfectly safe. That is obviously absurd. However, the more of a design margin you have, the less meticulous you have to be when preparing to launch the vehicle. Almost all the cost overruns in the shuttle program are due to the incredible number of inspections and maintenance needed to turn a shuttle around. With a throwaway booster, you don't have any of that. Sure, you're junking valuable hardware every time you launch with a throwaway booster, but it actually costs less to do it that way. Why do you think commercial satellites are launched on Delta rockets instead of the shuttle?
Take a modern top-fuel dragster as an example. It is designed to do one thing: go as fast as you can in one quarter of a mile. Everything inside the engine is designed to last roughly just that distance, and it is torn down and rebuilt pretty much completely between every run. It is, in essence, a throwaway booster. Dragster teams do it this way because it is impractical to build an engine that can survive multiple runs and be competitive. Sure, it's expensive. But losing the race is even more expensive.
NASA needs to get away from giving us a Ferrari of a shuttle, with all its myriad valves, camshafts, and amazingly expensive maintenance, and instead give us a slightly-updated version of the 60's-era Chevy Big Block. Sure, a Ferrari can get 400hp out of a 2.5-liter engine, but it must use exotic techniques to do so. A big block V8 can make 400hp all day long without working hard, and it costs pretty much an order of magnitude less to construct and maintain. We need the Chevy, not the Ferrari, if we're going to get back into space on a large scale.
In the end they will lay their freedom at our feet and say to us, Make us your slaves, but feed us. - Fyodor Dostoyevsky
And if it has a hole in it and shouldn't? Bond-o. Doesn't have a hole in it and should? Sledgehammer. Point well made with WD-40, but a real redneck might have tried Crisco first since the kitchen's closer than the shed.
Even the smallest stray piece of material can cause disruption upon re-entry.
The utter fragility of such a system is proof enough the design is tragically flawed. If a billion dollar vehicle can be taken out by such a simple failure, something is wrong. Would you accept such SPoF's (Single Points of Failure) in any I.T. system you're responsible for designing or maintaining? I mean, it's not like we can't make something better than the current tile-and-felt the shuttle uses. Apollo-era capsules had monolithic, non-reusable ablative heatshields that were far less fragile, and the capsule design was elegant enough to protect the heatshield with other portions of the spacecraft until it was actually time for re-entry.
The shuttle was, is, and remains, a boondoggle. It was not a step forward from Apollo, it was a leap backwards.
In the end they will lay their freedom at our feet and say to us, Make us your slaves, but feed us. - Fyodor Dostoyevsky
The problem with the O-ring in the SRB had nothing to do with the heat shield of the orbiter. Challenger could very well have had a completely pristine thermal protection system and would still have been destroyed.
The post you replied to is correct -- while there have been problems with tile damage in the past, dating back to the very first mission (although the problematic area was later covered with thermal blankets rather than tiles, so the problem can't recur) -- there have been no cases of severe orbiter damage in the past due to tile/RCC damage.
i am a soviet space shuttle
Hell, everything about Russian (and Soviet before that) industrial design focused on simplicity and maintainability to the exclusion of features. Given their resource constraints, that absolutely makes sense, and they still managed to pull of some amazing design wins with what they had to hand. Prime example that comes to mind is the Mig-25, an interceptor capable of mach 3+ flight at the edge of space, built using things like riveted steel and vacuum tubes. Other examples of "simple, kind of ugly, but works without fail" abound in their weapon systems designs (SKS, AK-series, T-34 and descendents, etc. etc.)... (They did focus too much on that, but given how many times they've been invaded in their culture's history it is kind of understandable. Ultimately they built better guns, we built better blue jeans, and consumer products/culture did more to bring down the iron curtain than any armed force.) Our aerospace community could learn a lot from their design ethos.
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The gear lowering switch is also there because the astronauts wanted there to be a function that the computers couldn't do so that a crew would always be required.
The gear and doors are mechanically connected so that if the gear door opens, the gear must come down. If it does not, there are explosives that will force the doors open and the gear down. That's how important it is.
There is no gear retraction mechanism switch because there is no need to be able to raise the gear again and the system would be just dead weight. The gear comes down only in the last seconds before landing.
i am a soviet space shuttle
Since the end of the Cold War many have over estimated how good, the simple reliable Russian system were. They had some good designs, but they have had alot of utter crap.
Okay, I misunderstood the "Everything was going good for 20 years" comment. In the context of just the TPS, there have been no major disasters in the history of the STS prior to the final flight of Columbia. I was thinking of the STS as a whole. My bad.
That said, I still stand by the rest of my comment. The fact that it problems never resulted in a disaster prior to 2003 does not mean that there were never any serious problems. I see this attitude all the time and it's wrong. People get away with doing stupid things for a while -- years, sometimes. Then, for whatever reason, they stop getting away with it and come to me and say, "Fix it", and won't listen when I point out that it is their behavior that is the problem.
"We've always done it that way" makes a lousy epitaph.
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I do not like Microsoft. Remove them from my email address.
The SR-71 can maintain Mach 3 (the aircraft can fly Mach 3.3 what limitations in the handbook has yet to be declassified) while the Mig-25 can only fly at 2.83 for limited amounts of time. The SR-71 has a range of 2,900 miles unrefueled, while the Mig-25 has 537 miles in the same conditions. The SR-71 routinely flew at 80,000ft, while the Mig-25 had a maximum service altitude of just over 67,000ft.
How much the Mig-25 actually cost to develop and produce is unknown, just going by the cost per an aircraft is not a accurate measure because the Russian Air Force already ate the cost of the aircraft development, while when you talk about cost per an aircraft in US circles, we talk about total cost of the project divided by the number of aircraft produced. Which is why many aircraft top a billion per an aircraft.
page 4 from this NASA PDF:_ tps.pdf
http://www.nasa.gov/centers/kennedy/pdf/91372main
Gaps and Gap Fillers The gaps between the tiles, which range from 0.028 inch to 0.200 inch are necessary for two important reasons. The first reason concerns the difference in thermal expansion properties between the tiles and the orbiter airframe. When in orbit, the external temperature fluctuates by as much as 400 degrees F. The tiles contract much less than the airframe, due to differences in the thermal expansion; thus, the gaps are required to accommodate the difference. During reentry the gap dimensions are also critical. As the orbiter descends through the ever-thickening atmosphere, pressure gradients cause the plasma surrounding the orbiter to flow. If the gaps are too large, hot gases can flow through the gaps and can cause damage to the backup surface seals (filler bar). Gap fillers are used extensively to control the gap dimensions between the individual tiles in many areas of the orbiter and in some areas to provide mechanical 'padding' between the tiles.
The Stone Age did not end because humans ran out of stones. - William McDonough
With you at NASA's helm, we'd never have found out if mice could sort tiny screws in space.
Moof!