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NASA Space Science

Space Shuttle to Receive Emegency Repairs 427

Posted by timothy from the friendly-callers dept.
Tycow writes "The BBC are reporting that Discovery needs emergency repairs - dangling material has been spotted on the belly of the shuttle, and NASA are worried they could cause overheating on re-entry. 'Nasa is concerned the dangling material - called gap fillers - could cause part of the shuttle to overheat as it re-enters the atmosphere.The type of repairs being planned have never been conducted by astronauts on a spacewalk before.'"
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Space Shuttle to Receive Emegency Repairs More

Space Shuttle to Receive Emegency Repairs

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  • Tough cloth (Score:2, Interesting)

    by fembots ( 753724 )
    According to NYTimes, this is what they're planning to do:

    The astronaut would first try to remove the cloth, which is glued in place, by pulling it out with his gloved hand, she said. If that failed, he would use a set of forceps to tug the filler out or to hold the cloth while he cut it off with scissors, she said.

    Are they saying that this piece of cloth (which may be removed by (1)pulling it out with bare hand, (2)poking it out or (3)cutting it off with a pair of scissors) won't simply burn away during re

    • Re:Tough cloth (Score:4, Informative)

      by ranson ( 824789 ) * on Monday August 01, 2005 @09:11PM (#13219083) Homepage Journal
      (Sorry I pressed the wrong reply button the first time i posted this response) No it won't burn away, the cloth is ceramic-coated with the same material as the thermal tiles on the orberter belly; they can withstand thousands of degrees farenheit. The protrusions will break away some, but in past landings, they have measured protrusions of at least one half inch AFTER the craft has landed and the protusion was manipulated by the landing approach. There was no way to know how big the protrusions were prior to landing because they couldn't examine the craft to the level of detail they can post-Columbia.
    • The material in question is Nextel 312 SF 2600. Asbestos is flammable in comparison.
    • The danger is that tugging and pulling at the cloth just might loosen some vital piece (e.g. a tile) of the spacecraft.

      In order to deal with this matter appropriately, the engineers in Houston should create a similar scenario (i.e. a loose cloth) on the remaining shuttle and attempt to yank at it. Then, the engineers should determine whether another piece of vital equipment might be dangerously and excessively dislodged by the yanking. This sort of simulation and estimation should be done before you tell

      • I neglected to add the following.

        The safest thing to do is the following.

        We should ask Moscow to send a spacecraft to the space station and to safely return the American and Japanese crew members back home. Then, we give the American and Japanese engineers time to simulate and study the mechanisms that caused the cloth to dangle loosely. Also, the engineers simulate what would happen if someone attempts to yank the cloth off. In other words, we make 100% sure that all is well.

        Then and only then,

      • Actually I thought I heard this morning that they had already simulated this procedure using a full scale mockup in Nasa's Underwater pool.
  • ... the proverbial klingon?
  • emegency

  • I hope they remembered (Score:3, Funny)

    by MrShaggy ( 683273 ) <chris.andersonNO@SPAMhush.com> on Monday August 01, 2005 @09:06PM (#13219061) Journal
    he type of repairs being planned have never been conducted by astronauts on a spacewalk before.'"

    Did they bring the duct tape ? Wouldn't want to be the one that was supposed to but forgot.

  • ...and? (Score:3, Insightful)

    by rincebrain ( 776480 ) on Monday August 01, 2005 @09:08PM (#13219070) Homepage
    The type of repairs being planned have never been conducted by astronauts on a spacewalk before.

    How is this noteworthy at all? There are infinitely more repairs that haven't been done by astronauts on a spacewalk than have. It's not all that unusual; hell, cleaning off a mysterious stain on the outside of the craft would apply.
    • It's noteworthy because a TPS repair (no, not those infamous reports) has never been attempted in space before, and also because no spacewalker has ever ventured underneath (as would be underneath if it were flying level in the atmosphere) the orbiter before. The RMS by itself cannot reach these areas and the Manned Maneuvering Unit has not been used since the 1980s, so there is no tetherless spacewalk capability anymore.
      • "the Manned Maneuvering Unit has not been used since the 1980s"

        I just watched Star Trek: First Contact, and they had these magnetic boot thingies to walk on the ventral side of the saucer section. It should be no problem to use those on the shuttle.

        Why yes, I *am* a rocket scientist!
        • Actually, while I was thinking about it, I realized NASA should just remodulate the deflector dish to emit an inverse tachyon beam. That should take care of the problem.
        • I'm not sure how serious you are ... but just in case you're semi-serious, I should point out that that sort of thing wouldn't work -- the tiles are made of glass and aren't magnetic, and suction cups wouldn't work in space, and the hold-down shoes used on Skylab depended on a specially-designed 'floor' to have something to grab on to.

  • Tough Cloth (Score:3, Informative)

    by ranson ( 824789 ) * on Monday August 01, 2005 @09:09PM (#13219072) Homepage Journal
    No it won't burn away, the cloth is ceramic-coated with the same material as the thermal tiles on the orberter belly; they can withstand thousands of degrees farenheit. The protrusions will break away some, but in past landings, they have measured protrusions of at least one half inch AFTER the craft has landed and the protusion was manipulated by the landing. There was no way to know how big the protrusions were prior to landing because they couldn't examine the craft to the level of detail they can post-Columbia.
    • The cloth wouldn't burn away anyhow.

      The pressure of the orbiter moving at 25x the speed of sound when it hits the atmosphere is what causes the heating - similar but much greater magnitude than pumping a bicycle pump.

      The cloth can erode at that temperature and pressure, though. They found 1/4 in. fragments sticking out before, but no one knos if they fragments were larger in orbit.

      This may be a non-problem found in the pressure to find problems, and if they seriously ding the orbiter during repair, a

  • Paranoia. (Score:5, Insightful)

    by Inominate ( 412637 ) on Monday August 01, 2005 @09:11PM (#13219082)
    It's a minor problem, which ordinarily would have gone unnoticed. It's probably happened many times before. NASA is just being paranoid because they can't afford another accident. Alternative theory, NASA wanted to find something wrong that isn't really a danger and prove they can fix it, and that there is no danger anymore in space travel.
    • It's the former of the two. While I can understand it, currently it's a bit much -- but it's the "better safe than sorry" mentality.

    • Re:Paranoia. (Score:5, Interesting)

      by rhadamanthus ( 200665 ) on Monday August 01, 2005 @09:26PM (#13219154)
      NO. Boundary layer transition is not a very well understood phenomenon to begin with, and in this case you pushing the limits of both flight experience and analytical capability. Going from laminar to turbulent flow above mach 18 results in some very serious heating, ultimately effecting not just the thermal system, but also the structural margins.

      Most importantly, this trip would spill over the side of vehicle and run down streamlines into the wing leading edge. Analysts put the increased heat loads even in a "best case" situation at 80% increase. At those temperatures (almost 3300F), the SiC coating will start to degrade. Dispersion in the entry tajectory could lead to an additional 150F. At that temperature the SiC will ablate, exposing the carbon-carbon substrate. It will oxidize and the temperature will skyrocket to 4000F. At that temp kiss the wing goodbye.

      That all being said, I think it could make it down - the uncertainty in this situation is increasing conservatism - but I sure as hell won't take that risk when the EVA is quick and relatively simple.

      • Analysts put the increased heat loads even in a "best case" situation at 80% increase.
        Have you got a source for this? TFA said 10-30%, as have others I've seen.

        • Re:Paranoia. (Score:3, Informative)

          by rhadamanthus ( 200665 )
          30% on the tile. 80% at mach 19 early boundary layer transition on the WLE.

          My source is my job. :)
          • Ah, I see. How likely is it for the boundary layer transition to occur as early as mach 19? And obviously the position of the protruding gap fillers is a critical factor in all this - do you know whether the position in this case is a major concern?
            • Best estimate is actually worse - Mach 21.5

              In this case, as the gap filler is pretty far forward on the nose, the boundary layer is very thin and easy to trip. The position is key - forward and slightly outboard so that it overheats the WLE. In fact, one could argue that this is quite possibly the worst possible location for a protrusion of this size.

      • It's a good decision from the viewpoint that they need experience doing this and it's a great excuse.

        One major consideration was the possibility of damaging the oribter in an unnecessary repair. I hope it's unlikely. These guys aren't exactly like me doing plumbing, so that should help.

        It's a pity they couldn't have mounted a "scratch shuttle" for this flight and flown it with "scratch monkeys."

        (Am I now so old that no one else will get the joke?)

        • It's a pity they couldn't have mounted a "scratch shuttle" for this flight and flown it with "scratch monkeys."

          (Am I now so old that no one else will get the joke?)

          You might be old. On the other hand, you might just have read The New Hacker's Dictionary, or its current incarnation, The Jargon File. :-)
      • Back in the 70's they didn't know if it would be laminar or turbulent, so they designed for the worst case. That means that the shuttle is designed for a turbulent flow and more heating. It results in about 2 times the amount of thermal protection than it actually needs.

        One of my professors even speculated that this was the reason it too so long to lose a shuttle due to damage to the thermal protection system. Its just been over built.
      • Seems to me they'd want to stuff it back in rather than pull it out though... unless they're going to treat the hole as a "damaged tile" and try some of the filler goop to fill it...
    • You know, that's what I thought at first, too. But lets remember Discovery is 21 years old now. If you had a 21 year old car, would not not treat it a little more gently than something new? Would you not expect a few maintenence issues?

      The real issue here is the amount of time (and money) now being spent on each shuttle mission. Soon the crew will have just enough time in orbit to make sure they can get home, and that'll be about it. SOMEONE REPLACE THE DAMN THING ALREADY!!!!

      And let me take Atlan
      • You know, that's what I thought at first, too. But lets remember Discovery is 21 years old now. If you had a 21 year old car, would not not treat it a little more gently than something new? Would you not expect a few maintenence issues?

        If I drove my car as often as a shuttle launches, then, yes, I would expect it to behave as new. Keep in mind, many of the tiles are replaced after every flight.

        The big problem is that I don't think NASA believes in maned spaceflight. It seems like the only reason they do it

    • It's a minor problem, which ordinarily would have gone unnoticed.

      You mean stuff like slightly damaged booster seals and small pieces of foam hitting the wing that happens all the time?
  • It seems from this, and other articles, that NASA are rightly taking a conservative line on issues with the shuttle's heat shielding. After the high profile Columbia disaster, it can only be a good thing that the additional information gathered and attention paid to the heat shielding has found these kinds of problems early and given opportunities for them to be repaired whilst there is an opportunity. After the mistakes made previously, I'm sure the entire organization are pulling on all the resources poss
  • I'm guessing they're working on the movie right now. Happy ending? To be determined...
  • why didn't they send them up with a bunch of Super Glue??

    Cutting the material off is risky, they might slip and gouge a tile, pulling it out doesn't sound too good either, at least in my mind.

    Seems Super Glue is in order. I would think they would have some on board, maybe on the ISS???

    • Part of the mission was to test the use of such a compound on a spacewalk.

      On the first spacewalk of the mission, Noguchi will open this [package of pre-damaged Shuttle parts] and attempt to repair the tiles using a sticky, thick grey substance called "emittance wash".

      Robinson will then test a crack repair technique using a material referred to as Noax, for Non-Oxide Adhesive Experimental.

      http://news.bbc.co.uk/1/hi/sci/tech/4676473.stm [bbc.co.uk]
  • That's the end of manned space flight in the US. I don't even think commercial manned space flight will be permitted.

    • Re: (Score:3, Insightful)

      by account_deleted ( 4530225 )
      Comment removed based on user account deletion
      • Whatever the outcome, the USA surely does not want to let China or the EU get ahead in that field...

        It's already bound to happen. We're killing innovation in the US with a suffocating tidal wave of patents and litigation, and completely de-emphasizing mathematics and sciences in the educational curriculums... putting up an appearance of being ahead in space flight can only last for a few more years. The foundation is rotting away.

        • putting up an appearance of being ahead in space flight can only last for a few more years.

          Discovery is in orbit right now, it was the first launch after Nasa spent a billion dollars and a couple years 'fixing' a problem. The problem is not fixed. I dont think congress (or the public) is willing to risk another billion dollars on the hope the folks at nasa can get it right with another go at it. There is a very high likelihood that the shuttle will not fly again after this flight.

          The current agree

  • This is one of those "this has a one in 5,000 chance of causing any problem, and a 1 in 20,000, chance of being dangerous." Problem is, if you screw up AGAIN, on THIS mission, people are gonna be a lot more upset. So they are being extremely paranoid.

    Now this is good that they are looking over things more closely and seeing problems like this, but they are reacting probably too much to the problem. I'd be willing to bet this has been an issue since the first shuttle flight, that they simply hadn't notice
    • This is one of those "this has a one in 5,000 chance of causing any problem, and a 1 in 20,000, chance of being dangerous."

      Are we pulling numbers out of our ass now? I'm sure that if NASA knew that the chance of trouble was 1 in 20000 they wouldn't have even considered this problem. There's a much greater chance of damaging the space shuttle by trying to fix it.
    • Being a little extra-cautious is a good idea when there's lives at stake. With the current track history of shuttle problems and the fact that the entire world wants to know what's going to happen, I think it's in order.

      All of these things will give them valuable data for future missions. They'll try to repair the thing, and even if they aren't successful they'll know what they'll need to do next time. If it works, they'll have a better understanding on what needs to be done to prevent the damage and/or

  • I hope the shuttle comes home safe... (Score:5, Insightful)

    by ChiralSoftware ( 743411 ) <info@chiralsoftware.net> on Monday August 01, 2005 @09:29PM (#13219174) Homepage
    I hope the shuttle comes home safe and then gets parked in a museum. The problem here is that the heat shields are exposed to stress during both launch and entry. All other spacecraft have a heat shield that is only used one way or the other way, and then is disposed of. It's a bit much for me to want to reuse something that has to be exposed to the rigors of launch and then reentry and then be reused. I'm glad that it has worked as many times as it has in the past but this does not seem like a safe design and does not seem like the right thing to use to protect astronauts. The heat shielding is the one part of the shuttle that has no redundancy; if tiles are lost in critical places, the shuttle disintegrates.

    It also seems like they have spent a large fraction of their space-time on this mission simply making sure the shuttle is fit to return to Earth, rather than doing useful space work. The shuttle was sold on the promise of routine, cheap, quick flights to space, and we have something that flies so irregularly that it's hard to even say how often it flies (once a year or less?). It's such a bucket of bolts that astronauts then have to spend half their time just inspecting it for damage while they're in orbit. NASA should not be putting astronauts at risk in a ship like this. NASA should be spending its budget on programs that have a future, rather than programs which have been a dead end for a long time.

    ------------
    mobile search [mwtj.com] - coming soon

    • There is no such thing at least on manned flights, maybe fixing the hubble counts, that that is about it.
      • Yep, and it's this attitude which will doom the US space program, sooner or later. The problem is that the people in charge happen to think the same as you. Space is just a really really really big lab for doing science as far as NASA is concerned. They don't even care if or when that science results in benefits for the whole of human kind. That's why average people have no idea what the space program achieves. How could they, NASA isn't required to justify its existance and therefore it doesn't.
    • I don't see why they don't use the technology they used to use in the Apollo missions; a nice space capsule on top of a heavy-lifting rocket. It seems to be working pretty well for the Russians, right?

      And it seems to me that those capsules were a little bit safer than the shuttles.

      Can't they use capsules until the civilian companies perfect their plane-to-orbiter technology? Or would that be too embarassing for NASA?

    • I hope the shuttle comes home safe and then gets parked in a museum. The problem here is that the heat shields are exposed to stress during both launch and entry.


      Amen! I say we replace it with a nice space elevator, so that you don't need much in the way of heat shields at all -- you can go up and come down at a nice safe sub-sonic speed, and there's no mucking about with funky ceramics or exotic aerodynamics (or dangerous explosives, for that matter).

      • no mucking about with funky ceramics...

        What do you think that 200-mile cable is going to be made out of? Steel!? If it isn't ceramic, it'll definitely be a polymer and an engineering design that will be spooky as hell until we've used it a lot.

        And won't things be exciting the day that we learn that steady UV bombardment and ionic disturbances have caused the space elevator to age prematurely...

        Man, listening to slashdotters talk about space exploration rates a step above reading about it in Wierd Science
    • This being the case and given how delicate the heat shield tiles are, I wonder why they don't put some protective coating over the tiles during launch and just let that coating burn off during reentry. Most of the friction is in reentry as the shuttle tries to shed velocity, not on liftoff.

      Similarly for the foam I've heard people jokingly suggest a hair net... I always wondered why they can't embed some form of mesh inside the foam to add strength and help prevent it from sloughing off.

      -Aaron
      • In both cases: weight is a big limiting factor. If they add some type of extra protective covering to either the orbiter or the tank, that's a whole lot of weight that they can't put into a payload now.

        You don't want to combine an ablative (burn-off) heat protection with the tiles. When the ablative layer burns off, it doesn't just disappear; you have chunks of it flying off at high velocity that could cause more damage.

        As for the tank, I'm not sure what they'll do to stop the foam fall-off. One possibil
    • The shuttle was sold on the promise of routine, cheap, quick flights to space, and we have something that flies so irregularly that it's hard to even say how often it flies (once a year or less?).

      Blame it on congress and cost cutting.

      The original Shuttle designed called for a reusable pilot-able booster ratter than solid boosters and a foam-covered fuel tank (I've seen this referred to as a dual-stage maned orbiter-launcher).

      The model was even shown on Discovery's "Return to flight" special on Daily Planet

  • nasa should talk to riaa (Score:5, Funny)

    by yagu ( 721525 ) * <yayagu.gmail@com> on Monday August 01, 2005 @09:30PM (#13219177) Journal

    I don't know why anyone hasn't thought of this before, maybe it's just seredipity on my part. NASA should talk with the packaging industry, e.g., RIAA and how they package CD's (don't remember the last time I've opened a CD without it damaging the knife, jewel case, my hand, etc.), or the computer industry. I just purchased a logitech mouse and after what I went through to get the friggin' mouse out of its packaging, I'm pretty sure some of these materials and techniques could be useful in creating a more sound Shuttle. Certainly they're at least up to re-entry heat and forces.

  • Certainly not a Military Budget (Score:3, Insightful)

    by vandan ( 151516 ) on Monday August 01, 2005 @09:42PM (#13219220) Homepage
    If only the US Government spent a tenth of the amount that they spend on Weapons of Mass Destruction (tm) on their space program, maybe in-flight repairs wouldn't be necessary.

    Actually, a tenth would be way too much. The Iraq adventure is costing American citizens $US 1 billion per day ... and they've been there for years now. Maybe 1/100th is all that would be needed.

    • Re:Certainly not a Military Budget (Score:2, Informative)

      by Anonymous Coward
      The Iraq adventure is costing American citizens $US 1 billion per day ... and they've been there for years now.

      That's too high by a factor of about five. The National Priorities Project is claiming a total of $204.6 billion [costofwar.com], for a little under three years (which is to say, about a thousand days). Your number would see them spending a cool trillion in that time.

      They're still spending way too much, of course, but let's not make up silly numbers.
    • I agree with you 100% vandan. America NEEDS to get its priorities straight.

      If NASA could even have months worth of the money going to the war, then they'd probably be able to redesign the entire shuttle as a luxury line shuttle.
  • the repairs involve high tech duck tape or a swiss army knife.
  • My lesson of the day would be when to use "is" and "are".

    NASA is the name of an organization. It's a singular noun, not a plural noun. You'd say, "NASA is", not "NASA are".

    I can understand if the person is from Europe where the grammar rules are different, but I see many Americans not being able to speak their primary language.

    That is all.
  • I grow weary of the numerous slashdotters and beyond who piss and moan about the shuttle: It's too old, It's too expensive, It's too much hardware, It's not enough hardware, My TI calculator has more processing power. Blah blah blah.

    If you people--and you know who you are--really want the shuttle replaced, elect someone with a clue. If they don't care, demand to know why not. Encourage others to support candidates who enjoy more than a passing acquaintance with our history as a space power. Make well-reason
  • They have just spent a billion dollars to fix it, and it's still fucked up. Not to design, test, and build a new one, nor even to do any significant redesign. Just some refactoring and repairs. Four times the cost of the Mars rovers (still working, BTW), so that a few people can ride around in orbit and say how cool the view is from up there.

    Of course, the fanatical believers in manned space flight would never even consider that this shows the monstrous demerits and grotesque waste of manned flight versus

    • Re:again, the waste that is manned space flight (Score:4, Informative)

      by TopSpin ( 753 ) * on Tuesday August 02, 2005 @04:12AM (#13220230) Journal
      Of course, the fanatical believers

      Ad hominem

      in manned space flight would never even consider that this shows the monstrous demerits and grotesque waste

      Our species is trying to figure out how to do this. It's hard. It takes time and costs lives and great treasure. Fifty years from now some nameless mech will be strapped to the side of a cracked hull trying to patch a hole with a Shuttle derived glue gun.

      Take the long view. It's easier on the blood pressure.

      of manned flight versus unmanned.

      There is no versus. Cassini is filling basements full of storage devices with Saturn and its moons. Deep Impact's primary objective was fulfilled only one month ago. In 2003, WMAP (and COBE before it) nailed the age of the universe to within a couple hundred million years. CLOVER and the Planck Surveyor will improve on this. Gravity Probe B is concluding its mission in August. NOAA-N launched in May. Spitzer (2003) and Chandra (1999) are both functioning well. Here is a page [nasa.gov] full of on-going unmanned missions you probably can't even identify.

      GOES-N launches in 3 days. Mars Reconnaissance Orbiter is launching in 6 days. CALIPSO goes up next month. STEREO, ST5, GOES-O, AIM, THEMIS, Pluto New Horizons and Dawn are all launching in 2006. Phoenix launches in 2007.

      There is no verses. We do BOTH. We have the means and we're using it, regardless of what fools like you think you know.
      • There is no verses. We do BOTH.

        It is that there is both which creates the versus. Whereas I agree with you in principle - manned spaceflight is critical to the sort of growth, development and refined understanding which will lead to automation handling these tasks, that does not justify turning a blind eye to the legitimate comparison between manned and unmanned approaches to tasks.

        regardless of what fools like you think you know.

        Tsk, tsk, this is the same sort of personal attack you pointed out in the par
  • What makes this shuttle mission different is that they now have new views of the space shuttle. So they are equipped to see and fix problem areas they were previously ignorant of. They have landed with dangling gap filler before. However now because of Columbia that are very wary of such things. So this repair is more of a "just in case" scenario rather than "omg the shuttle is going to blow up".

    A good recap [pbs.org] (RealPlayer) can found from the News Hour on PBS.
  • From TFA:

    "This is the new Nasa. If we cannot prove this is safe, we don't want to go there. It exceeded our threshold and we needed to take action," Mr Hale said.

    Spaceflightnow.com:

    "Today at the mission management team meeting we had a very long discussion about aerodynamics," Hale said. "I went in with a very simple question: Did we have the engineering knowledge and analysis that would, without a shadow of a doubt, allow us to be 100 percent confident the vehicle could fly safely during entry?

    "without a s

  • The real reason isn't because it's an emergency! (Score:5, Informative)

    by BritImp ( 795629 ) on Monday August 01, 2005 @11:20PM (#13219588)
    I spoke with a guy from the Mission Management Team (MMT) tonight here in Cape Canaveral. He confirmed that such small pieces of gap filler are not expected to affect the creation of the barrier layer during re-entry, and so do not pose a threat to the orbiter.

    The real reason for this 'repair' is because this whole mission is to "test orbiter repair techniques" - and these virtually irrelevant pieces of gap filler provide an unexpected, but very fortunate opportunity to try a real repair technique out in a relatively safe and controlled fashion.

    NASA doesn't yet know if it's even possible to have an astronaut perform repair-type work on the underbelly of the orbiter - they think it would be possible, but they have no hard data to say it can be done.

    But these small bits sticking out give them the perfect excuse to go test it and get some real-world experience on the issue.

    If it looks like the astronaut might damage some of the Thermal Protection System tiles down there, they'll just terminate the repair attempt and fly home as-is. If not, they'll demonstrate that astronauts can go under an orbiter and perform repair tasks down there safely and without harming the TPS.

    But I'll bet you'll hear the popular press making too much out of this as usual...

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