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NASA Releases Columbia Crew Survival Report

Migraineman writes "NASA has released a 400-page Columbia Crew Survival Investigation Report [16MB PDF.] If you're interested in a detailed examination and timeline of the events leading to the destruction of Columbia, this is well worth the time. The report includes a number of recommendations to increase survivability of future missions." Reader bezking points out CNN's story on the report, which says that problems with the astronauts' restraint systems were the ultimate cause of death for the seven astronauts on board.

36 of 223 comments (clear)

  1. ultimate reason for the astronauts death by Anonymous Coward · · Score: 5, Insightful

    Is not the restraint systems. No restraint system could have saved them. The fact that their vehicle was disintegrating from burning up might have something to do with it.

    1. Re:ultimate reason for the astronauts death by MobileTatsu-NJG · · Score: 4, Funny

      Is not the restraint systems. No restraint system could have saved them. The fact that their vehicle was disintegrating from burning up might have something to do with it.

      Ack!! Not everybody read the article first. Use the spoilers tag!!

      --

      "I like to lick butts!" by MobileTatsu-NJG (#32700246) (Score:5, Informative)

    2. Re:ultimate reason for the astronauts death by flaming+error · · Score: 4, Funny

      With a proper seat belt-airbag system, they might have been encapsulated in a wind vortex which insulated them from the heat of re-entry and cushioned their impact as they bounced across several Texas counties. Just sayin'.

    3. Re:ultimate reason for the astronauts death by JCSoRocks · · Score: 5, Insightful

      Yeah, this is a bit like driving your car off of a mile high cliff and saying that the restraint system is the reason you died... yeah... you know... that or the impact and the ensuing fireball.

      --
      You are using English. Please learn the difference between loose and lose; they're, there, and their; your and you're.
    4. Re:ultimate reason for the astronauts death by mea37 · · Score: 5, Insightful

      That's one way of looking at it.

      However, the actual cause of death was apparently trauma that would not have occured had the restraints been better designed / utilized, and that information is of practical value to future vehicles and missions. That's the whole point of the report.

      That they would've died of another cause, doesn't change that they did die of the stated cause.

    5. Re:ultimate reason for the astronauts death by SecurityGuy · · Score: 5, Insightful

      Spoilers.

      The report doesn't list a cause of death, it lists five events which were sufficient to cause death, the first being cabin depressurization, and IIRC, the second was the restraint system failing to keep their upper bodies immobilized as the crew compartment tumbled, resulting in what would have been lethal injuries. For the pedantic, yes, the report implies they were alive when these injuries occurred because their circulatory systems were still functioning. I parse that to mean there was associated bleeding.

      Thermal injury would, of course, have been fatal, but by the time they were exposed to re-entry heat, they were no longer breathing (no heat related injuries in the lungs).

      The final potential lethal event was ground impact. And actually, if they'd been in pressurized suits AND the restraint system didn't fail, they'd have likely lived until the crew compartment disintegrated and they were exposed to reentry heat. As it was, they fell unconscious almost immediately after depressurization.

      It's a fascinating report, with what I gather are the more graphic bits redacted. It's quite a thorough and professional job, and though it talks about seats and functions, there's always the awareness that you're reading the story of the final moments of real people, and that the whole point of the report is that we might do a better job of protecting our future astronauts.

    6. Re:ultimate reason for the astronauts death by amRadioHed · · Score: 5, Informative

      Actually the cause of death may have been the trauma, or it may have been the rapid depressurization preceding that. The report wasn't able to determine which was the actual cause.

      On a positive note however, at least it seems the depressurization knocked them unconscious quick enough that they didn't suffer much.

      --
      We hope your rules and wisdom choke you / Now we are one in everlasting peace
    7. Re:ultimate reason for the astronauts death by OglinTatas · · Score: 3, Funny

      "As it was, they fell unconscious almost immediately after depressurization."

      And that is a mercy. As the joke goes: I'd rather die peacefully in my sleep, just like grandpa, rather than screaming in terror like his passengers.

    8. Re:ultimate reason for the astronauts death by pushing-robot · · Score: 5, Funny

      You drove your car off a cliff. Moments before your car hit the ground, I plugged you right between the eyes with a sniper rifle. Your car hits the ground and creates a dramatic fireball. How did you die?

      Awesomely.

      --
      How can I believe you when you tell me what I don't want to hear?
    9. Re:ultimate reason for the astronauts death by Sloppy · · Score: 3, Insightful

      The real question is, would you really want to keep the crew alive through the early parts of such a catastrophic failure just so they could be burned to death a few minutes later?

      NASA's position is going to be Hell Yes. If you can keep 'em alive a little longer through such a catastrophic failure, then you can probably also keep 'em alive longer through a less catastrophic failure.

      They're going to be thinking, "Ok, what if some astronauts suddenly find themselves in a spin but they're not re-entering an atmosphere at the moment. Do we want their upper bodies to flop around until half their bones are broken, or do we want them pinned to their seats for a few seconds muttering, 'HAL, engage spin recovery' and then live happily ever after?"

      The result being an edict handed down: put on your seat belts.

      --
      As copyright owner of this comment, I authorize everyone to defeat any technological measure which limits access to it.
    10. Re:ultimate reason for the astronauts death by prisoner-of-enigma · · Score: 4, Insightful

      The real question is, would you really want to keep the crew alive through the early parts of such a catastrophic failure just so they could be burned to death a few minutes later? In other words, should NASA act on what they've discovered in this report, or should they just let things be and accept that when a spacecraft breaks up on reentry, the crew is going to die?

      I've got another option: how about NASA not using a spacecraft that is required to violate its own design criteria in order to function.

      In case you're unaware of it, Thermal Protection System (TPS) design criteria were that the tiles would not be exposed to debris impacts during launch. Since the very first launch of the Shuttle, tile dings have been recorded despite the fact that the tiles were never designed to deal with impacts. This should have sent up a huge red flag at NASA. For some engineers, it did. But the problem was the fundamentally flawed design of the entire Shuttle system, namely that of having the exposed TPS tiles alongside the External Tank (ET), which being full of liquid hydrogen and oxygen was guaranteed to produce ice debris. Since NASA accepted and built a known-flawed design, they couldn't "fix" it without scrapping the entire Shuttle system. Since that wasn't an option, NASA crossed its fingers and rolled the dice...again, and again, and again...until people died.

      Thermal protection materials are, by their very nature, fragile materials. So long as our space program relies on either thermal tiles or ablative shielding, that re-entry system must be protected from damage during launch and spaceflight. The only way we can do that (with existing technology) is to put the crew module above anything that's likely to produce debris. We had that on Mercury, Gemini, and Apollo. We'll have it again for Ares or whatever the next administration decides to fund after the Shuttle is thankfully and deservedly retired.

      --
      In the end they will lay their freedom at our feet and say to us, Make us your slaves, but feed us. - Fyodor Dostoyevsky
  2. Why did it took this long... by grub · · Score: 5, Funny


    Columbia Crew Survival Report:
    They didn't.

    --
    Trolling is a art,
  3. dumbification by spikeham · · Score: 5, Insightful

    The mainstream media once again lives up to its long history of mangling science stories.

    The report cites 5 specific fatal aspects of the loss of Columbia: depressurization, extreme dynamic loads, separation of the crew from the vehicle, exposure to space, and ground impact. Implying that this really means inadequate restraint systems is a joke. No amount of safety hardware would permit surviving the breakup and uncontrolled re-entry of (pieces of) your spacecraft.

    Due to NASA politics, the report omits a more accurate summary statement that the Shuttle is an inherently flawed and unsafe design when compared to ballistically stable capsules that can and do survive uncontrolled re-entry.

    http://3.paulhamill.com

    1. Re:dumbification by spikeham · · Score: 5, Informative

      In April 2008 a Soyuz made an uncontrolled reentry due to failure of the service module to separate during the de-orbit sequence. The cosmonauts survived due to the inherent ballistic stability and fail-safety of the design:
      http://www.spectrum.ieee.org/may08/6229

      NASA has finally conceded that the safest place for the astronauts is on top of the launch stack, with abort rockets to escape a failing lower stage, and with no exposure to damage from falling debris. These factors plus the increased safety of ballistic reentry explain the return to capsules with the Constellation system.

      Shuttle vs. Soyuz Reliability
      http://forum.nasaspaceflight.com/index.php?topic=7954.0

      Soyuz vs Shuttle
      http://salul.wordpress.com/2008/09/25/soyuz-vs-shuttle/

    2. Re:dumbification by avandesande · · Score: 3, Informative

      Capsules don't rely on tiles but instead use single-ablative shields that are protected during the entire flight until reentry.
      After each launch the shuttle has to be completely rebuilt so there weren't any cost savings.
      A little more about problems with the shuttle design by a Nobel-Prize winning physicist....

      http://www.fotuva.org/feynman/challenger-appendix.html

      --
      love is just extroverted narcissism
    3. Re:dumbification by trappermcintyre · · Score: 4, Interesting

      You know, for an 'inherently flawed and unsafe design' it did pretty well for almost 30 years, outliving it's expected life by, what, 15?

      I would be inclined to think that the reason it "did pretty well" is more to do with beating the odds than good design or good management. Read what Richard Feynman had to say about his role on the Challenger investigation board (Rogers Commission) in "What Do You Care What Other People Think?". It's fascinating. The people on the ground who had the most to do with the Shuttle put the odds of a catastrophic mission failure at much shorter odds (1 in 100 ISTR) than managers (something like 1 in 100,000 - sorry for not being more precise I don't have the book to hand). These were the same managers who were much less obsessed with the safety of the shuttle and crew than they should have been and pushed for launching when they shouldn't have done. I suspect managers with similar figures for failure in their heads were the ones to ignore concerns of more junior staff when the hole was first detected.

      At the point where the shuttle broke up it was obviously a non survivable event, but I'm of the opinion it didn't have to be if appropriate steps had been taken when there was first a problem detected. I also feel anything they can learn now from Columbia to help design a better vehicle that ups the odds of surviving a catastrophic failure in future is a good thing.

      To go back to my original point, I do think it is extremely misguided to say that just because a thing hasn't happened before means it is safe or well designed - it may just mean that so far it's beaten the odds, and I don't think that should be overlooked by NASA when they come to finalise future designs, or plan future missions.

  4. CNN? Restraints? Oxymoron? by arizwebfoot · · Score: 5, Funny

    Lets try this CNN,
    we'll put you in your car with tight seat belts
    then we'll put a bomb under the car and ignite
    then we'll test if the restraints had any impact on your ability to survive.

    Assuming of course there is anything left of you to test.

    --
    Beer is proof that God loves us and wants us to be happy.
    1. Re:CNN? Restraints? Oxymoron? by Cochonou · · Score: 5, Funny

      Don't be too rude with CNN. The actual NASA report, while very comprehensive and well written, still contains little gems such as:
      For the first 15 to 20 seconds, the modeled loads would not cause serious injuries to a conscious crew member who was capable of active bracing. An unconscious or deceased crew member would have been more susceptible to injury.

  5. Pretty amazing forensics by Tibor+the+Hun · · Score: 5, Insightful

    I am always amazed at the quality of forensics in cases like this, or aviation accidents and such.

    I mean this thing exploded, or better yet disintegrated how many hundreds (thousands) of meters in the sky, scattered its debris all over BFE, and yet they can still piece together enough information to deduce who was unbuckled, who wasn't wearing gloves, and who didn't have their visors down.

    --
    If you don't know what AltaVista is (was), get off my lawn.
    1. Re:Pretty amazing forensics by Anonymous Coward · · Score: 3, Informative

      They knew all that mostly from a video of the re-entry taken seconds before the shuttle disintegrated. They didn't piece it together from the wreckage (apart from finding the video tape in the wreckage).

    2. Re:Pretty amazing forensics by darkmeridian · · Score: 4, Interesting

      The most amazing forensic work I read of was the Lockerbie bombing of a TWA flight while in midair. The debris was scattered over many square miles. Yet the investigators were able to reconstruct the bomb and find the bomb's timing circuit. A chip in the timing circuit was traced to the perpetrators.

      That was pretty fucking cool, I thought.

      --
      A NYC lawyer blogs. http://www.chuangblog.com/
    3. Re:Pretty amazing forensics by advocate_one · · Score: 4, Interesting

      Actually the debris field was a total of approximately 1000 square miles. The total search area was several times this size, as they had to be sure that they covered it all.

      That was an absolute bummer of a job... I spent several days walking the fields around Lockerbie as a member of a search party looking for remains and marking the positions for the recovery teams... I still have nightmares about some of the scenes we found... a row of seats with all the occupants still in it, rooks and other carrion birds pecking the eyes out of bodies...

      --
      Donald 'Duck' Dunn: We had a band powerful enough to turn goat piss into gasoline.
  6. Cascading failure by Draconi · · Score: 5, Informative

    The report lists the immediate causes of death as depressurization, and then trauma (not properly restrained, or failure of restraint for upper body and head in sudden depressurization) for those who survived even that long.

    Each event listed after is in of itself certain death, and the report makes sure to say that even if everyone were wearing their full equipment and had been properly restrained, there was no way to survive - there simply isn't a way for our current equipment to "eject" or have a "safety capsule."

    The things we can take away are that all signs point to sudden, painless deaths well before breakup, and that the things learned in the investigation can be applied for greater safety in future missions.

  7. Sugar-coated death notice by RobertB-DC · · Score: 5, Interesting

    I'll admit, I'm a bit more morbid than the average bear. But the report is heavily sugar-coated, with the obvious goal of making sure nobody thinks anyone "suffered". That's the biggest thing in American culture, it seems; "At least they didn't suffer". When my grandfather died of a heart attack, someone told my uncle something about massive "blood clots in the heart" indicating that he "didn't suffer".

    Sorry, I don't buy it. At least, not the Disney-fied public-consumption version.

    The Spaceflight Now summary notes five "lethal events", and implies that the *first* one caused immediate unconciousness:

    * Depressurization
    * Buffeting without being fully buckled in
    * "Separation of the crew from the crew module and the seat"
    * Exposure to near-vacuum
    * Impact

    The claim that the initial "depressurization" would make the crew "incapacitated within seconds" relies on the common perception that exposure to the vacuum of space makes your face explode. That's not the case, as has been explained over and over -- you can't breathe (" respiration ceased after the depressurization" in the report), but not breathing hasn't been the criteria for "death" since the Middle Ages.

    It's the second one that probably did most of the crew in. The crew compartment started spinning and tumbling, and "As a result, the unconscious or deceased crew was exposed to cyclical rotational motion while restrained only at the lower body." I would say that "unconscious or deceased" is window dressing, like hoping that the girl from "Dead Like Me" would grab you just before your car runs off a cliff.

    But even that assumes that "the seat inertial reel mechanisms on the crews' shoulder harnesses did not lock". I kinda thought that's what seat belts were *supposed* to do. So I can only assume that at least some of the unfortunate crew made it to phase three, which is awfully hard to make sound pretty. "Separation of the crew from the crew module and the seat" sounds almost gentle, but what it means is that the forces were eventually so great that their bodies were ripped apart by the very straps designed to hold them in place.

    Unfortunately for those who want their dead to enter the next world peacefully, I think it's pretty likely that the crew's last experience was anything but a peaceful passing from lack of oxygen.

    Now, is that so awful? I don't think so. I don't even like to ride a roller coaster, myself, but these were a bunch of adrenaline junkies strapped to a freakin' ROCKET. These weren't people who planned to die in their sleep. I would imagine that all of them -- and especially the pilots, who were almost certainly strapped in and helmets on -- would want to go out kicking, screaming, and pushing every possible button to try to turn the damned thing around.

    They died with their boots on. Give them that, at least.

    --
    Stressed? Me? Of course not. Stress is what a rubber band feels before it breaks, silly.
    1. Re:Sugar-coated death notice by Darth_brooks · · Score: 4, Interesting

      But even that assumes that "the seat inertial reel mechanisms on the crews' shoulder harnesses did not lock". I kinda thought that's what seat belts were *supposed* to do. So I can only assume that at least some of the unfortunate crew made it to phase three, which is awfully hard to make sound pretty. "Separation of the crew from the crew module and the seat" sounds almost gentle, but what it means is that the forces were eventually so great that their bodies were ripped apart by the very straps designed to hold them in place.

      No, they didn't. Read the whole report for yourself, it'll change your POV pretty quickly.

      If you look at the time lines the crew had, at the absolute most, 12 seconds before loss of consciousness once the cabin depressurized. The telling fact was this: None of the crew had closed the face shields of their helmets, which is a requirement to use supplemental oxygen supply (one of the crew didn't even have their helmet on when the problems started). The G load on the shuttle never really exceeded 3.5 G's (the roll rate was only 30-40 degrees per second initially) until the shit really hit the fan, which was long after loss of cabin pressure. The force on their bodies wasn't enough to prevent them from doing so, so they must not have been able to do so.

      Based on the reconstruction of the flight deck, and the data gathered, the report lays out the last few seconds like this: Tire pressure sensors go off the scale. Ground control sees this, confirms with crew. Master alarm event goes of, Crew tries to communicate with ground control but is cutoff, likely due to a planned radio outage between comm centers. In their (unbeknownst to the crew) remaining few seconds of consciousness the flight crew begins to troubleshoot what appears to be a loss of hydraulic pressure issue which may be tied to what they are now seeing as a possible landing gear problem with the left gear. The nose pitches up, cabin depressurizes and the crew is almost certainly rapidly incapacitated, as evidenced by the stop in troubleshooting procedures. As compared to Challenger, where several members of the crew took deliberate steps to follow emergency procedures (turning on oxygen supplies, etc.)

      Bottom line, even if they knew the cabin depressurized, they didn't have time to take even the first and most basic corrective step in their training before passing out. You'd think it'd be instinct. Maybe they didn't *die* due to a lack of oxygen, indeed they almost certainly died of blunt force trauma. The lack of oxygen just ensured that the deceased had no idea that they died of blunt force trauma. Like lethal injection. The first drug puts you out, the second drug paralyzes your heart.

      The report is very morbidly interesting, and I think you'll see a lot of procedural and technical changes come out of this, just like with Challenger. There are a ton of "wow, yeah, that makes sense now" safety procedures that would've altered the outcome slightly. In this case, we'd have had astronauts ripped apart, burned to death, or killed on impact rather than asphyxiated / bludgeoned to death. Maybe next time, something we learned here will actually save a life. We can only hope.

      --
      There are some people that if they don't know, you can't tell 'em.
    2. Re:Sugar-coated death notice by DerekLyons · · Score: 4, Interesting

      Bottom line, even if they knew the cabin depressurized, they didn't have time to take even the first and most basic corrective step in their training before passing out. You'd think it'd be instinct.

      You'd think it would be instinct - but there is a flaw in the astronauts training... The report discusses this, but I suspect the implications will fly right past most laymen.
       
      The flaw can be basically summarized as follows;

      • They are trained in the event of an emergency to close their visors - but emergency training is done separately from operational training.
      • Operational training conditions them to keep their visors up and their gloves off because when the suits are fully buttoned up they interfere with crew communication and restrict their ability to operate the equipment.

      Because emergency and operational training were performed separately, in simulators designed specifically for each purpose, the subtle difference between what they were trained to do and what they were conditioned to do wasn't caught.
       
      It was assumed that they would perform properly in an emergency because they had been trained extensively on what to do in an emergency - but NASA never performed any training scenarios that transitioned from emergency operations to emergency survival. The main reason for this, which does make some sense to one who has been there (having done this kind of training), is that you don't need to practice dying - it doesn't accomplish anything positive, can be damaging to morale and crew cohesion, and consumes valuable and scarce training resources.
       
      Disclaimer: I'm not an astronaut, but I don't count myself a layman because I am a former submariner. I've done countless operational and casualty drills both as a crewman and as an instructor at a training facility. We spent a lot of time making sure we didn't start getting into what we called 'negative training', one facet of which is the difference between training and conditioning I discuss above. (And its a remarkably easy trap to fall into.)

  8. Extreme forceful asphyxiation by Anonymous Coward · · Score: 5, Informative

    I believe the actual cause of anyone's death when suddenly exposed to the extreme thin (lack of) atmosphere at high altitudes, is extreme forceful asphyxiation.

    At 30,000 feet MSL, the healthiest humans can only maintain consciousness about 1.5 minutes max.

    At 35,000 feet MSL you'll last only about half as long... 45 seconds max.

    At 40,000 feet MSL, after rapid decompression, you might stay conscious for 25 seconds if you're in excellent shape.

    Remember the Payne Stewart LearJet crash? They lost cabin pressure and the plane on autopilot went up into the flight level 40's.

    Above 50,000 feet you must wear a pressure suit in addition to breathing supplemental oxygen... unless you're inside a pressurized aircraft/spacecraft.

    At 63,000 feet MSL, all the gases dissolved in your blood boils. You die in seconds if exposed to rapid decompression.

    The Columbia began it's breakup around 200,000 feet MSL and most educated guestimates place the altitude where the pressurized crew compartment broke away from the rest of the craft at around 100,000 feet and that it held its pressure until about 60,000 feet until it broke open.

    The ballistic trajectory of the big chunks of what was left of the ship took a sharp downward turn once it reached about 40,000 feet MSL due to all the pieces slowing down so rapidly and then fracturing into such small pieces as to next be more accurately called a debris cloud in the relatively thick atmosphere of 35,000 feet compared to where the breakup first began.... at least that's what the math models derived from the shape and size of the debris field on the ground seems to suggest.

    One thing that always amazes me, and that most people don't even understand is that the actual atmospheric air pressure difference between here on the ground and being in the "vacuum" of space, is only 14.7 teeny-tiny pounds per square inch.
    That's right. Less than 15 measly PSI. Fifteen PSI ain't even enough air in your car tire to make it roll very well. And that's all the difference there is between ground and space. Space is not some huge gigantic super vacuum that'll crush a strong metal container as if it was a beer can. Space is actually a quite subtle difference in pressure from what we breath here on the surface, especially when you compare it the pressure difference to what you'd find a only a few thousand feet under the sea.

    1. Re:Extreme forceful asphyxiation by Da+Cheez · · Score: 3, Informative

      Terribly sorry to reply to my own post, but I located a Wikipedia article with useful information on this subject.
      It would seem that in my previous post I was (at least partially) correct.

    2. Re:Extreme forceful asphyxiation by 0xdeadbeef · · Score: 4, Informative

      http://imagine.gsfc.nasa.gov/docs/ask_astro/answers/970603.html

      exposure to vacuum causes no immediate injury. You do not explode. Your blood does not boil. You do not freeze. You do not instantly lose consciousness.

    3. Re:Extreme forceful asphyxiation by sam_v1.35b · · Score: 3, Interesting

      Space is actually a quite subtle difference in pressure from what we breath here on the surface, especially when you compare it the pressure difference to what you'd find a only a few thousand feet under the sea.

      At only 10 meters (c. 30ft) beneath water you're exposed to twice the pressure you experience at sea level. It then increases by about 1 atmosphere per 10 meters. So, at one hundred meters it's an order of magnitude higher. You don't even need to go a few thousand feet under the sea to experience significantly higher pressure.

    4. Re:Extreme forceful asphyxiation by evanbd · · Score: 3, Interesting

      I'm not trying to challenge what you're saying (too much) or start an argument, but I'd just like to see an original source for that. I've often heard that even in complete vacuum a healthy individual will maintain consciousness for 10 to 15 seconds and then have another couple minutes or so before they asphyxiate.

      That's basically correct. In vacuum exposure, your blood does not boil, but since your lungs still work all the dissolved gases (like oxygen) in your blood leave through your lungs. 15 seconds is about how long it takes the extremely deoxygenated blood to reach your brain, at which point you suddenly black out. There are plenty of other things that go wrong in vacuum exposure, but that's the first one. Note that this is much faster than asphyxiating from breathing an inert atmosphere, which is faster than from being unable to breathe.

      Holding your breath doesn't work; your lungs can't contain enough pressure to help. You'll just get a ruptured lung, which is a medical emergency even if you were in a hospital and not exposed to vacuum.

    5. Re:Extreme forceful asphyxiation by tlhIngan · · Score: 3, Interesting

      At 63,000 feet MSL, all the gases dissolved in your blood boils. You die in seconds if exposed to rapid decompression.

      The Columbia began it's breakup around 200,000 feet MSL and most educated guestimates place the altitude where the pressurized crew compartment broke away from the rest of the craft at around 100,000 feet and that it held its pressure until about 60,000 feet until it broke open.

      Guess what that fancy orange suits that they wear on liftoff and re-entry are for! Yes, they're pressure suits.

      When the shuttles first came out, the crews would all don those pressure suits on both legs of the trip. Then as the shuttles came into regular use, they didn't wear them anymore - you can see this in the crew photos taken at launch. They'd go in initially in the suits, then a few years later, they were going up in blue flight suits. This happened until Challenger exploded, and the crew died from hypoxia. Now they all don those suits again, in case of any issues on liftoff. Part of the launch and re-entry procedures actually involves doing a pressure test to ensure the suits seal properly, and they close their helmets.

      Of course, if the shuttle disintegrates on them, well, those suits don't protect much against your whole vehicle burning up and taking out your life support as well.

    6. Re:Extreme forceful asphyxiation by jeremyp · · Score: 4, Funny

      Leela: Depth at 45 hundred feet, 48 hundred, 50 hundred! 5000 feet!

      Farnsworth: Dear Lord, that's over 150 atmospheres of pressure.

      Fry: How many atmospheres can this ship withstand?

      Farnsworth: Well it's a spaceship, so I'd say anywhere between zero and one.

      --
      All I want is a secure system where it's easy to do anything I want. Is that too much to ask ~~ Randall Munroe
    7. Re:Extreme forceful asphyxiation by evanbd · · Score: 3, Interesting

      Not true. Hyperventilating gets (at best) a little extra O2 in your blood, but mainly just drives down the CO2 level. Since your breathing reflex is controlled by CO2, not O2, this makes it easier to hold your breath -- but disproportionally so compared to how much more air you really have available. Hyperventilating will make it much easier to pass out. Furthermore, your lung tissue is really just an exchange membrane -- it holds almost no oxygen. In a vacuum exposure situation, your lungs are exposed to vacuum. You *cannot* hold your breath because your lungs aren't strong enough. As blood passes through your vacuum-exposed lungs, essentially *all* the dissolved O2 and CO2 leaves (remember, your lungs are quite efficient as exchange membranes). The blood leaving your lungs is now completely devoid of O2, regardless of anything you did or didn't do before the decompression event. Once that blood hits your brain, you *will* lose consciousness. That takes about 15 seconds.

  9. Mount Everest Altitudes by sjbe · · Score: 3, Interesting

    At 30,000 feet MSL, the healthiest humans can only maintain consciousness about 1.5 minutes max.

    Citation please.

    You are saying that despite the fact that mountaineers have summited Mount Everest which is 29,029 feet MSL (8,848 meters) without supplementary oxygen that they would only last for 1.5 minutes just 1000 feet higher? Sorry but I'm having a hard time swallowing that one. Yes it is very dangerous for anyone to be above about 26,000 feet (8000 meters) - it's called the death zone for a reason - but it seems to me that people can very likely last longer than 1.5 minutes at that altitude even assuming rapid decompression.

  10. Re:Put the people in a "black box"! by Plekto · · Score: 3, Interesting

    The real cause, though, appears to have been a design change in the shuttles. Originally the design called for titanium throughout the ship instead of aluminum. But it was deemed to be far too expensive when they were first built, so they went with Aluminum.

    As a result, it weighed a LOT more, which required heavier shielding with less margin for error, the solid fuel boosters(added), and it barely made it into orbit instead of being able to get up to nearly geostationary orbit as originally planned. And it was much harder to fly and land - so much so that it really "flies" more like a typical plane with its engine off.(read: like a brick).

    Compare the heat resistance of the two metals. I suspect that if the wings had been made out of titanium, it would have taken another minute or two to reach a catastrophic failure. This *might* have been enough to at least get into the lower atmosphere.(in theory allowing some sort of ejection/safety system to function?)

    http://en.wikipedia.org/wiki/Space_Shuttle_thermal_protection_system
    ****
    The Space Shuttle thermal protection system (TPS) is the barrier that protects the Space Shuttle Orbiter during the searing 1650 C (3000 F) heat of atmospheric reentry.
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    Aluminum melting point: 1220 F Aluminum burns at ~6920F once it starts doing so, though, and as such is pretty near self-sustaining and impossible to put out as long as there is material to burn.

    Titanium melting point: 3034 F Titanium burns at ~ 5300F once it gets going and is just as hard to put out. (burning metals like this are bad as a rule)

    A drastically lower weight, though, would also allow for a slightly slower speed. Likely closer to 2500-2800 F which would technically make the heat shielding a redundant safety feature, at least on the wings.(they would melt and distort, but wouldn't actually catch on fire.