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NASA Space Science

NASA Decides No Fix Needed for Endeavor's Tiles 209

bhmit1 writes "It looks like NASA is reporting that no repairs are needed for Endeavor. 'After meeting for five hours, mission managers opted Thursday night against any risky spacewalk repairs, after receiving the results of one final thermal test. The massive amount of data indicated Endeavor would suffer no serious structural damage during next week's re-entry. Their worry was not that Endeavor might be destroyed and its seven astronauts killed in a replay of the Columbia disaster — the gouge is too small to be catastrophic. They were concerned that the heat of re-entry could weaken the shuttle's aluminum frame at the damaged spot and result in lengthy post-flight repairs.'"
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NASA Decides No Fix Needed for Endeavor's Tiles

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  • by ExE122 ( 954104 ) * on Friday August 17, 2007 @09:12AM (#20260583) Homepage Journal

    Their worry was not that Endeavor might be destroyed and its seven astronauts killed in a replay of the Columbia disaster -- the gouge is too small to be catastrophic. They were concerned that the heat of re-entry could weaken the shuttle's aluminum frame at the damaged spot and result in lengthy post-flight repairs
    And I'm sure thats the only thing the astronauts were worried about as well... the precious shuttle.

    It reminds me of a while back when a friend of mine called his mother to tell her he had a few drinks and was gonna stay the night at a friend's house. Her response was, "Yeah, I wouldn't want anything to happen to the car."

    Regardless, I admire their fortitude given the history of the Columbia and all that has happened. I hope everything goes well and they get home safely.

    --
    Captialism: When it uses the carrot, it's called democracy. When it uses the stick, it's called facism.
    • IANAAE (Score:4, Insightful)

      by Stanistani ( 808333 ) on Friday August 17, 2007 @09:25AM (#20260753) Homepage Journal
      Here's where we get to watch a lot of folks decide whether to comment on the effects of something outside of their experience and expertise.

      I've seen photos and 3D imaging of the bashed tiles. I know very little of the forces involved. I have seen no structural analysis of the materials that are beneath the deepest part of the gouge.

      To a limited extent, I can compare this damage to the past damaged tiles. There seem to have been a number of similar damaged tiles in the past, and those flights landed safely.

      The astronauts could slap some of that goop on the gouge, but risk damaging the tiles by accident, or changing the aerodynamics of the craft.

      There are many unknowns. I really don't know what will happen when Endeavour reenters.

      I wish them well, and hope that NASA can complete the remaining shuttle flights without mishap.
    • As a former USAF avionics specialist and later crew chief, one thing was always true:

      The decision about air-worthiness, mission-worthiness was the pilot's, the aircraft commander.

      It didn't matter if I told him that sure, the plane will fly, if he didn't like it, the plane didn't fly.

      So, NASA, provide all the information to the commander, pilot, and crew, and let THEM make the call. If you don't like what they decide, it can be taken up AFTER the mission.

      • by Billosaur ( 927319 ) * <wgrother@optonline . n et> on Friday August 17, 2007 @09:51AM (#20261111) Journal

        But that's the difference between an aircraft and a spacecraft -- an aircraft pilot can look his plane over, read up on the maintenance, talk to his ground crew and then decide to fly or not. In NASA, it works differently. A Space Shuttle commander has command of the spacecraft, but Mission Control in Houston has command of the mission. You have to remember: the crew of the Shuttle can't just go bombing around in Earth orbit like they are flying the Millennium Falcon. Every move has to be choreographed and planned out months and even years in advance. When unexpected problems crop up, the technicians on the ground certainly know more about the workings of the machine than the crew, as they have all the data at the fingertips, they are experts in their systems, and they can draw on contractor resources to get more information. Decisions like this cannot be left to the spacecraft commander; his/her job is hard enough without having to keep in their head the compendious amount of information regarding their spacecraft.

        It has been this way since Mercury; it was Chris Kraft who outlined the need for the ground to have the skills required to manage the mission and deal with problems in real time, so that the crew could concentrate on their activities in space. The system has worked extremely well over all these years, with the exception of the Columbia accident. I for one am confident that NASA knows what it is doing and will take all the precautions it can before Endeavour is allowed to land.

      • "As a former USAF avionics specialist and later crew chief"

        Egads, there's another one???
        "328Xwhatevers x-trained to Nosepickers" represent!
        I did it to escape Moody in the F-4 days, but it sure made promotion testing easier.
        • by WED Fan ( 911325 )

          Wow, I ended up cross training several times.

          Started out as a cop at RAF Upper Heyford, went back to Lackland as an MTI, then A-10 gun, then Avionics and finally chief on the C-5's out at Travis.

          There were bonuses or really good training locations each time I did that. If you count Biloxi as a really good training location.

      • He can decide not to return to earth, but they are on the clock, they got to come home sometime :) He can have all the balls in the world but when the power goes out, and the CO2 levels start rising, and the food supply is running low (whatever order it occurs) ... its life or death. On earth it isn't.
        • by WED Fan ( 911325 )

          He can decide not to return to earth, but they are on the clock,

          Not the only choice, Sparky.

          • Fly it home, unfixed. Maybe burn up.
          • Return it home, unmanned. If it burns up, relief. Go home in Soyuz.
          • Fix it, fly it home.
          • Park it, fly home in Soyuz (in shifts because of number of people). Repair on subsequent flight, or when repair kit is sent up on next Soyuz.

          Does anyone see a need for a better lifeboat than Soyuz?

          • * Fly it home, unfixed. Maybe burn up.

            And follow orders from Houston. So much for sticking it to the man.

            * Return it home, unmanned. If it burns up, relief. Go home in Soyuz.

            Believe it or not you actually need a pilot for the first few and last few moments of reentry. See below for my Soyuz comments.

            * Fix it, fly it home.

            Not sure how feasible this is without ground support. They may or may not have written procedures onboard.

            * Park it, fly home in Soyuz (in shifts because of n
            • by WED Fan ( 911325 )

              Fly it home, unfixed is what Houston has ordered. Hopefully the man who made decision has signed his name to it.

              Soyuz - There are 2 available, the stationed there is set up for remote all the way. They have the supply craft available, for remote all the way. All the parts are available, the Russians actually have several near completion at all times, they could have a new supply craft ready to go before food and air stores get too critical. Remember, the shuttle has some as well. The Russians have an incre

              • Re: (Score:3, Interesting)

                by everphilski ( 877346 )
                Fly it home, unfixed is what Houston has ordered. Hopefully the man who made decision has signed his name to it.

                The decision is by committee. The consensus to fly home was made last night and was unanimous among the committee. They did extensive analysis both with CFD, analytical models and arc jet testing.

                They do have procedures, and materials. Since the last disaster, they have sent up patch kits. If its not adequate, they can send up one that is on the next go round. They chose not to patch because
                • by WED Fan ( 911325 )

                  There are several places, but the best source is the current schedule.

                  Space Flight Now is an excellent resource. You may not know this, but, the 40 year average for Soyuz launches is 5.3 per year, with a much faster pace now.

                  Launch Dates

                  Currently ready for flight, waiting for payload or just its time:

                  • Sep 14 - Non-ISS but could always be refitted.
                  • Oct 10 - ISS mission
                  • TBD - Unknown mission (military?) with a launch somewhere between the preceding and following
                  • Dec 23 - Non-ISS, from what I know, but ag
                  • I know the schedule, I know SFN and other sources, but that doesn't tell me the number of soyuz on hand. I did some reading about the assembly line efficiency of the Soyuz a few years back and it lead me to believe that they made 'em and lauched 'em, IE, there isn't a stockpile laying around.

                    And remember, looking at Soyuz entries on SFN, Soyuz is a vehicle, not a capsule. For example, the September 14 mission will NOT have a man-rated capsule aboard. It will have the Foton M3 microgravity research capsul
    • by Ed_1024 ( 744566 ) on Friday August 17, 2007 @09:30AM (#20260827)
      Subj: Space Shuttle

      However tempting it may be, given the considerable savings, please don't source any more tiles from "Home Depot".

      NASA Mgmt.
    • by Vellmont ( 569020 ) on Friday August 17, 2007 @09:38AM (#20260949) Homepage
      And I'm sure thats the only thing the astronauts were worried about as well... the precious shuttle.
      If the only thing mission control was worried about was "the precious shuttle", then they would have just sent them out right away to fix the gouge.

      Spacewalks are potentially dangerous. Micro-meteorites could tear right through a spacesuit and instantly kill an astronaut. They aren't taken lightly and are always judged whether the benefits justify the risks. In this case, they didn't.
    • And I'm sure thats the only thing the astronauts were worried about as well... the precious shuttle.

      From a certain point of view - that's all that really does matter.

      Astronauts are a dime-a-dozen. NASA currently has nearly 150 on the payroll - even if we fired the crew after each flight, we could fly 20 missions before we needed more. For every astronaut NASA currently has, there are 10 or more equally well qualified candidates available to be hired and trained.

      But the Shuttle itself is a

    • by khallow ( 566160 )
      Keep in mind that there are a lot of astronauts and only 3 shuttles. Their priorities are correctly placed whether you like them or not.
  • by Chairboy ( 88841 ) on Friday August 17, 2007 @09:21AM (#20260693) Homepage
    It's unfortunate, this could have been a good test case to see how the repair materials/procedures work under realistic conditions.

    Having firm, experimental data about:

    * The process of applying the patch
    * How well the patch stands up to re-entry
    * How well the patch protects underlying systems

    and more. Better to get this data on a 'non-critical' bit of damage than waiting until something is REALLY busted before finding the inadequecy.

    They've done extensive testing on the ground, I'm sure, but a real-world test scenario can trump ten lab extrapolations. That's why we do external betas of software, the real world always has something up it's sleeve.
    • by grommit ( 97148 )
      There's much safer ways to do tests like that in space. It would be trivial to create a small section of tiles attached to one of the robot arms and pre-gouge it. Astronauts could practice working on it. Why NASA hasn't done that, I don't know. I do think it'd be a good idea to have some sort of real-world test for these repairs.
      • Re: (Score:2, Interesting)

        by RoverDaddy ( 869116 )
        The Astronauts -have- practiced patching tiles in the cargo bay. But those tiles can't be on the outside of the shuttle during reentry.
        While I was writing my previous response I thought about the idea of 'pre-patching' some tiles near the rear of the shuttle before launch, in order to see how well those tiles did on reentry. Can you imagine the outcry if NASA suggested purposely -damaging- a few 'unimportant tiles' before the mission even begins? And I doubt you can easily add a few spare tiles to the a
        • Also, launching the shuttle with "pre-patched" tiles would mean that NASA still wouldn't have any data on the feasibility of applying the repair materials during the flight. Working in the cargo bay is one thing, but trying to repair tiles on the belly while attached to the end of the robotic arm is yet another.
    • Re: (Score:3, Insightful)

      by RoverDaddy ( 869116 )
      But most betas don't run the risk of killing 7 people. There are serious risks involved in -doing- the patch too.
      • "But most betas don't run the risk of killing 7 people. There are serious risks involved in -doing- the patch too."

        Yet another reason manned exploration using primitive technology is so limiting. We should park the shuttle and develop unmanned systems with self-repair capabilities.
    • Re: (Score:3, Interesting)

      by pilgrim23 ( 716938 )
      The tiles are extremely delicate. NASA viewed a lumbering astronaut in a suit ill designed for delicate work, with a tube of superglue and a squeege in the area around the main heat shield of the Shuttle a far greater threat then the small hole.
    • What's that mantra we IT folks keep repeating?... If it ain't broke, don't fix it.

      I'd argue it's better to wait until the shuttle's really busted before trying out complex repair maneuvers. In that case, the shuttle's already a writeoff; if the astronaut crashes into the tiles or they're otherwise damaged, it won't matter.
  • by pimpimpim ( 811140 ) on Friday August 17, 2007 @09:23AM (#20260711)
    Let's just hope they did't reuse their previous powerpoint presentation on the space shuttle [edwardtufte.com] as a template for this meeting.

    Now that link is a bit of a read, but a very striking introduction on influencing decision-making with presentation techniques, even if this costs other people's lives.

  • by Anonymous Coward
    ...or the shuttle's days will be numbered even if it is still a useful tool.

    Endeavour is currently on the sixth shuttle mission since Columbia was lost. On Slashdot there's a chance that somebody could tell you what was achieved on any of those six missions. Ask an average member of the public though, and I guarantee you that less than 1% have any idea of a single piece of scientific research achieved on any of those six flights.

    A large number of those members of the public will be able to tell you
    • Who cared about the space program after Apollo 11 other than nerds?

      Spirit and Opportunity have entered year three, well past their 90 day expected life span, yet I'd wager the lost Polar Lander and crashed Climate Orbiter got more press than the little rovers that could ever will.
    • This is only going to be fixed one way. NASA has to start giving out copious quantities of interesting video from shuttle flights to the media, and completely seal away from the media any talk of damage or problems. The damage has been of no real significance every time, but it is the only thing we're talking about.

      I wouldn't take NASA to task for not keeping the media up-to-date when you don't do so for yourself.

      NASA does give copious quantities of information to the media. (Video, still, and tex

    • >, and completely seal away from the media any talk of damage or problems.

      I was completely in agreement with you up until you dropped this one.

      The last thing we need is further adoption of the "Bush Doctrine" of suppressing any information that a government agency decides that the public doesn't need to know. I actually think it admirable that NASA is now so open concerning potential problems with shuttle flights, and would like to see it continue.

      Besides, if they were to hide such information, and an ac
  • "We're good to return without repairs? Ummm...tell you what, just drop me off at the ISS and I'll wait for the next shuttle, ok?"
  • by ubrgeek ( 679399 ) on Friday August 17, 2007 @09:28AM (#20260795)
    > after receiving the results of one final thermal test

    While playing Stairway to Heaven, bic lighters were waved back and forth over the affected area.
  • ...why don't they replace the tiles anyway, just to be sure? The article suggests that a spacewalk would create added risk, but we know that spacewalks occur all the time routinely. Perhaps there is a financial motivation for not carrying out the repair? I don't know. What I'd like to see is an actual breakdown of the possible positive and negative consequences of each course of action and the probabilities that NASA has assigned to the outcomes. I'm really hoping that they've put some serious statisti
    • They can't replace the tiles - the tiles are fitted to the shape of the Shuttle; every tile is different.

      They have a patch kit, but in applying the patch they could weaken the tiles that they're patching. So it's a tradeoff. If they perform the repair and all goes well, then they're probably better off than before. But if something goes wrong during the repair, things could get a lot worse.
    • Re: (Score:2, Insightful)

      It would be problematic to replace the affected tiles.....if I remember from old articles (don't have links, sorry), each tile is unique and not the same size as its neighbor (although they visually appear to be). You would have to grind it or somehow alter the shape to make it fit the hole precisely as it should.

      If they used the caulk, I would worry about the goop bubbling out or not being flush with the surrounding surface, thereby creating drag which may pull the whole tile out, which would leave a
    • Re: (Score:3, Insightful)

      by RoverDaddy ( 869116 )
      I read Osheroff's quote and decided he's talking out his ass (or it's a lousy quote). Perhaps successful repairs can only increase their chances, but things can and do go wrong, and it wasn't explained how Osheroff was in a better position to make the analysis than the people at NASA doing it. BTW, if you read the article carefully, it seems that financial considerations would lean toward doing the repair, not avoiding it. Leaving the gouge in place may result in more down-time and repair work for Endeav
    • by reality-bytes ( 119275 ) on Friday August 17, 2007 @09:43AM (#20261023) Homepage
      They can't actually replace entire tiles on orbit. They have a 'patching' system which allows them to spread a compound into any nicks in the tiles.

      Now, the compound has to be applied by an astronaut attached to a long extension arm attached to the Shuttle's robotic arm. When they tested this a few flights ago, it became readily apparent that it was at best difficult to work this way. The length of the arm caused significant 'bouncing' with every motion. At the time they only pulled a gap filler and simulated the motion of filling a tile and it wasn't easy.

      The real danger is that the control issues of having a 'massive' astronaut + EVA gear swinging around on the end of that very long arm so close to the TPS could actually cause more damage to the tiles than it fixed.

      Furthermore, the compound could actually cause even worse localised heating issues on re-entry depending on how well it fills the tile ie: It could cause ducting etc.
    • Re: (Score:3, Informative)

      by east coast ( 590680 )
      but we know that spacewalks occur all the time routinely.

      What's risky about this isn't the space walk itself but the concept of damaging more tiles. It's a delicate operation and one slip can make things go from bad to worse easily.

      Perhaps there is a financial motivation for not carrying out the repair?

      What financial motivation? The material already exist onboard. There is no investment and the amounts by which NASA would be set back in the case of a mid-air breakup or even a safe landing with an unus
  • by erroneus ( 253617 ) on Friday August 17, 2007 @09:50AM (#20261101) Homepage
    Man, that pretty much fixes everything... did they forget to pack any this trip?
  • Angry General:
    Son, what do you mean you've blown my multi-billion dollar shuttle ?

    Pissing-in-his-pants Soldier:
    Well, there was this small gouge you see, we had experts analyze it and they said it was not urgent.

    Angry General:
    you mean you wouldn't spend a few tens of thousand bucks to keep a multi-billion shuttle in good health ? I'll tell you what, why don't you and your experts go clean the toilets with your tongue while you think things through...
  • Ahem, I have some doubts about NASA's ability to predict tile-related events, based on their past record:

    • The first calculations about the aerodynamic loads on the tiles were waay off.
    • So far off, many tiles fell off when the Shuttle was carried on back of the 747!
    • The calcs about the damage to tiles from loose foam were also way off.
    • So I'd be rather dubious about any heat-transfer calculations from those same folks.
    • We will see.
    • Re: (Score:2, Informative)

      Which is why they are not relying on calculations. They actually grabbed some tiles, gouged them in the exact same form from the measurements taken in orbit and then put them in a hot wind tunnel (The Arcjet facility) to check what will actually happen
      see here [nasaspaceflight.com]
      And:
      here (with pictures). [nasaspaceflight.com]

      The tests at Arc Jet used a set of tiles, with identical damage drilled on to a test article. This was then put through the heat of a simulated re-entry, to test how the damaged area performed, along with the gathering of ther
  • I'm under the impression they've had dozens of defects more extensive than this one in the hundre-plus returns. At least they did laboratory tests and computer modeling of the exact defect they discovered this time.
  • ....NASA's in-space repair abilities that they spent gobs of money on after Columbia remind me a lot about our "Disaster Recovery" plans at my firm. Sure.. we have one; Sure.. we spend a lot of money on it;... but please.. oh please.. don't make us actually test it or put it into practice.

    I hope they didn't just spend all that money so that could check the "Disaster Recovery" check box on some form and quiet the complaints.

    • It has been *tested.* What you're suggesting is akin to taking down the company servers. The live servers. The servers that run the company. Not backups of the servers, not test boxes, THE servers. The ones that make you piss your pants on a simple restart no matter how redundant they are.

      NASA's tested applying the goop on practice tiles on the end of the arm. Here's the thing: the arm wobbles. the underbelly of the shuttle is fragile. Astronauts on an EVA don't exactly have the same forces availabl

      • NASA's tested applying the goop on practice tiles on the end of the arm. Here's the thing: the arm wobbles. the underbelly of the shuttle is fragile. Astronauts on an EVA don't exactly have the same forces available that we do to react instantly. Stuff floats out there, inertia, all that stuff. One wrong hiccup and that 400-500 pound weight is crashing into the shuttle and there's no way to stop it.


        Aren't these this kind of things that all that money and testing were supposed to account for?


        That's why the d
        • However, I can't shake the feeling that NASA simply doesn't have faith in there own repair techniques. It would make me very nervous if there was a warning label on a repair kit that said, "Last Resort Warning: Only use if you're pretty sure you're gonna die anyway."

          That pretty much sums up how I feel about any disaster recovery plan. It sorta hits close to home in a way for me, too, actually. We (well, I...) had to do that over the past weekend: we had a production server for a small business (read: too
  • Not making the repairs strikes me as odd. If it turns out that the gouge was too big we lose the crew (including yet another teacher) and the shuttle. And they'll never know if the repair would have saved them. If the gouge didn't need repairs we get to find out how the repairs hold up under real world conditions.

    Also, this would a chance to test the repair kits in a real world scenario. It's a simple 2x2 matrix of whether is works or not and whether it was needed or not. The only problem is if the repair d

    • by gclef ( 96311 )
      In case it wasn't blindingly obvious, moving around in space is hard. Your decision matrix is *far* larger than 2x2...there is no given that the application itself won't cause further problems.

      Imagine doing something that requires fine motor control (like, smoothly filling a space with fairly sticky stuff) under the following conditions:
      1. Your entire body is encased in a bulky 100-lb suit.
      2. Your hands are encased in enormous gloves that are effectively oven mitts.
      3. Any force you exert against the surface
  • Yeah, it's been quoted before, but we'll see if NASA has taken this to heart. Maybe, if they lose a third shuttle they will.

    For a successful technology, reality must take precedence over public relations, for nature cannot be fooled.

    . . . . . — Richard P. Feynman, Appendix F - Personal observations on the reliability of the Shuttle [nasa.gov]

    I would recommend they go ahead and test the goop in the shuttle bay and even paint it and see how it does in the vacuumn and exposed to sunlight for a day. Then th

  • So my Ti/carbon fiber bike is more advanced than the space shuttle? What was the reasoning for that design decision?

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