NASA Releases Columbia Crew Survival Report 223
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.
ultimate reason for the astronauts death (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.
Re:ultimate reason for the astronauts death (Score:5, 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!!
Re:ultimate reason for the astronauts death (Score:5, 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'.
Extreme forceful asphyxiation (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.
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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.
Re:Extreme forceful asphyxiation (Score:5, 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.
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At 63,000 feet MSL, all the gases dissolved in your blood boils. You die in seconds if exposed to rapid decompression.
In other words, my arteries and veins are wholly dependent upon atmospheric pressure to keep the gases in my blood from from boiling out as I type this?
Don't they have some structural integrity on their own? I would be surprised if they suddenly stopped working just because the surface pressure on my skin were removed.
Briefly surprised. Hopefully long enough to think "Hey, that AC was righ
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You're basically asking "You mean to tell me that the earth pushes back on the beams holding up my house? So it has no structural integrity on its own?"
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You're off by a factor of 144. 14.5 psi is 2088 psf. Multiply that by 16.1 to 21.5 sq ft!
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I think he totally made those numbers up. If anything, he's not taking into account arterial and venous blood pressure.
But no, you're not thinking of it correctly. Your blood will absolutely bubble violently throughout your body if you are saturated with gas at, say, 100 feet under water and pop right up to the surface. Your body is, except for the lungs, entirely uncompressible liquid. If you drop the absolute pressure enough, then, yes, the liquid will release its gases. And the water itself may boil.
Mount Everest Altitudes (Score:4, 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 [wikipedia.org] 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.
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He did say _sudden_ exposure. Mountain climbers take many days to acclimatise.
But posted anonymously and cited no sources. Sorry but I've got a bit too much skeptical scientist in me to buy that assertion at face value.
BTW Mountain climbers acclimate to avoid altitude sickness [wikipedia.org], not to avoid sudden asphyxiation.
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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.
Here's another way to look at that measly 14.7 PSI pressure differential - on a 1-meter diameter circular hatch, that's about 17,890 pounds of force. Or roughly 3.5 Ford F-150's, since this is Slashdot and car analogies are mandatory.
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Or roughly 3.5 Ford F-150's, since this is Slashdot and car analogies are mandatory.
How many Libraries of Congress is that?
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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.
Only? Atmopsheric pressure is comparable to the weight of a person on the palm of your hand. I'd call that pretty significant on the human scale.
Re:Extreme forceful asphyxiation (Score:4, Interesting)
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.
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It would seem that in my previous post I was (at least partially) correct.
Re:Extreme forceful asphyxiation (Score:5, Informative)
http://imagine.gsfc.nasa.gov/docs/ask_astro/answers/970603.html [nasa.gov]
Re:Extreme forceful asphyxiation (Score:4, 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.
Re:Extreme forceful asphyxiation (Score:4, Interesting)
Re:ultimate reason for the astronauts death (Score:5, Insightful)
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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 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?
Re:ultimate reason for the astronauts death (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.
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Screaming.
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One could also consider that the most prevalent restraint system for humans—gravity—was also a factor.
Re:ultimate reason for the astronauts death (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.
Re:ultimate reason for the astronauts death (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.
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But to read the report, it sounds almost as if they want to fix the restraints, and change the pressure suit procedures... so they can suffer more??? I know, they're looking to make "slightly less catastrophic" incidents survivable.
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This is why Scotty never bothered to install them. When going from Warp 8 to zero, seat belts are _not_ the issue
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This is why Scotty never bothered to install them. When going from Warp 8 to zero, seat belts are _not_ the issue
Lord Helmet begs to differ! [youtube.com]
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Re:ultimate reason for the astronauts death (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.
Re:ultimate reason for the astronauts death (Score:4, 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.
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Re:ultimate reason for the astronauts death (Score:4, Insightful)
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.
Re:ultimate reason for the astronauts death (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.
Clearly an intertial dampener problem (Score:3, Funny)
Did Dale Earnhardt die in vain?
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T
I believe you've missed the point (Score:3, Insightful)
There is no reason to design a retraint or any kind of protective system that would keep a person alive during that catastrophic breakup.
What they noticed is that the restraint system did not keep the astronauts alive during a situation where it could have.
What if there was an event that shook the cabin really hard, but was non-lethal? The current restraint systems would injure or kill the astronauts and turn a survivable event into a fatal one.
Having the best safety equipment is always the preferre
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That's silly it was because of lack of brain activity. That was when they were officially dead
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Why did it took this long... (Score:5, Funny)
Columbia Crew Survival Report:
They didn't.
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Spoiler Alert: Snape kills the Columbia Crew by throwing Rosebud through the heat shielding.
I'm sorry (Score:2, Informative)
The report is very clear: nothing could have saved them. The restraint system was certainly not the ultimate cause of death; it was perhaps an immediate contributor, but at best a minor one.
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I thought the report was fairly clear that the inadequate restraint system was probably the immediate cause of death, but that there were a long list of other things that would have killed them anyway after that.
dumbification (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
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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?
Regarding capsules, you're not exactly going to survive uncontrolled re-entry if, say, a tile breaks off or the parachutes fail to deploy. We've just had less capsule launches than shuttle launches.
The shuttle didn't break up due to uncontrolled reentry, either. The break up caused uncontrolled reentry.
As far as how the media's reporting it? Well...the media's filled wi
Re:dumbification (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/
Russia is safer than US space program? (Score:2)
Are you trying to say that the Russians are now safer than our American space system?!?!?
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Capsules are better than the shuttle, yes. Almost always have been, except for the few cases where you need to launch 40k+ lbs of payload AND 7 people all at once.
I'd mention quality control, but NASA hasn't exactly been immune to QC problems either.
As is usually the case, simpler = more reliable, and a capsule is far simpler than the shuttle.
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But they apparently haven't learned that multiple liquid-fuelled engines with one-engine-out capability are safer than solid-fuel rockets.
I don't think there's any hard data to support that allegation. Solid-fuel rockets are much simpler and thus more reliable (in general), albeit less efficient, than liquid-fuelled rockets, which makes them good candidates for the first stage. Which is where the shuttle and the proposed new system (Constellation/Ares I) uses them. The "one-engine out" capability of the shuttle isn't fully available at all times -- if the engine fails early, the shuttle must immediately return to the launch site, which is an
Re:dumbification (Score:4, 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 [fotuva.org]
Re:dumbification (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.
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The thing about the Columbia disaster is Nasa management willfully ignored evidence that there might be a major problem. Unlike the Challenger explosion, the Columbia was intact after the initial problem arose and yet Nasa management refused to allow staff to gather data that would show whether or not the foam impact had caused any damage.
Management claimed that even had they known that there was a problem, there would not have been anything they could have done to save the crew. One thing that's true about
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Regarding capsules, you're not exactly going to survive uncontrolled re-entry if, say, a tile breaks off...
Capsules don't use tiles. They use an ablative metallic heat shield, and heat shields don't break off--- they're essentially foolproof. The use of delicate ceramic tiles for heat shielding is one of the shuttle's many shortcomings.
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Spaceplanes don't have to use a ceramic tile, just the space shuttle, the way they designed it required either ceramic tiles or reusable ablative coverings (which was optional in the design for a while in case the ceramic tiles turned out to be impossible, but hasn't been mentioned since)
One aspect of the X-33 that never got tested (which bugs me) is the reusable refractory metallic heat shield. See, the denser the craft, the gentler the reentry. If the shuttle was less dense, perhaps by having the orbite
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That really doesn't do the report justice. You couldn't add magic restraints, better spacesuits, self-activating parachutes, etc. to the shuttle and expect for crewmembers to survive the accident, but there are a lot of more subtle design points to be made.
e.g. the example of the person who survived a SR-71 structural breakup, at even greater overpressure on the suit but with a more favorable thermal environment and while properly suited up.
The big and fairly underappreciated lesson of both shuttle acciden
CNN? Restraints? Oxymoron? (Score:5, Funny)
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.
Re:CNN? Restraints? Oxymoron? (Score:5, Funny)
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.
Put the people in a "black box"! (Score:2)
Those things are indestructible. Put the people in a black box and launch. If it fails, the people in the black box can tell us why. Seriously though, building a VERY destruction-resistant module could be the answer to the past and future problem of space traveller safety. But then again, some technologies currently considered science fiction might also have to become reality before such an idea is truly feasible. (Hey, I am NOT a Rocket Scientist....)
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There's also the issue of cost. As it is, getting into orbit is damned expensive. Hardening the shuttle, or some part of it, so it can survive catastrophic re-entry, even if possible, would make manned spaceflight prohibitively expensive. The best solution we have even for the next generation of craft is basically a rescue mission, because there's no feasible way to repair something as integral as a heat shield while in orbit.
As sad as the loss of Columbia, Challenger, and all the other losses of life in
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(boldface mine)
Lack of intelligent pork-barreling, more like it. If an important (read: expensive) part had been built in Wisconsin, Senator Wm. Proxmire wouldn't have, well, proxmired it down to the DC-1.5 level that it was. We might have had the original design with geosynchronus orbit cap
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The real flaw, but only painfully evident in retrospect, was not making something like the Saturn-Shuttle, like the X-20 atop a Saturn II, or even a reusable first stage for the existing stack. Likely taking a Saturn IB, II, or V stack and making it reusable bottom-to-top would have worked out far better.
The problem was barreling forwards with blinders on, not going back and checking assumptions. It wouldn't have been such an edgy design had it been more like the initial DC-3 concept or had they re-evalua
Re:Put the people in a "black box"! (Score:4, 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 [wikipedia.org]
****
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.
****
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.
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If you put people in an indestructible box you get people splattered over the insides of that box at impact, if not before. Suspending them in water or near-human density foam might keep them in one part until impact, but I suspect that the impact shockwave would still liquify bones and organs; the available deformation zone simply wouldn't be enough to decelerate a human body at a survivable rate.
You need some form of controlled deceleration or you're simply going to have a very bad day, no matter how inde
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Ah yes.... and if only someone would invent the parachute and retro-rockets...
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In a way, they've had it. In the form of the capsule approach. A good example is the Soyuz re-entry. As much of a debacle it was, they survived.
*If* a re-usable spacecraft design proves to be useful, the crew cabin may benefit from being a capsule that could somehow explosively decouple in an incident. Of course, chances are that it's just not worth it to reuse. Even if you had such a capsule, reliable separation such that a chute could be deployed successfully would be dangerous. Add to that the cost o
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Not even that.
Consider the A-10, with the titanium bathtub around the pilot so you can shoot all you want, but he's still sound.
Now, consider strengthening the crew cabin so that in the event of a structural breakup, they have a fighting chance of bailing out. No capsule. No separation. Just a little more plating or Titanium instead of Aluminum in the right spots. Remember, both the Columbia's and the Challenger's crew cabin held together for quite a long time.
Pretty amazing forensics (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.
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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).
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It must be awful to watch that tape, seeing the agony on the crew's faces as they realize their fate.
Where's the torrent link?
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I'm still waiting for the torrent of Steve Irwin. Yeah, I'm going to hell ;)
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Actuall
Re:Pretty amazing forensics (Score:5, 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.
Re: (Score:2, Insightful)
Not to sound like a 9/11 conspiracy theorist, but didn't they also supposedly find the passport of one of the suspects in the wreckage?
There's a fine line between pretty fucking cool and bullshit, IMHO. I know that saying that makes me sound like a conspiracy theorist, but I evade that label as I have no theory. I just think it's bullshit.
Re:Pretty amazing forensics (Score:5, Interesting)
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...
Re: (Score:3, Insightful)
Crew were incapacitated "within seconds" (Score:2, Insightful)
It appears that the pressure suits worn by the crew required user input to "configure the suit for full protection from loss of cabin pressure." Pardon my ignorance, but shouldn't a certain pressure be set as minimum survivable pressure, and a "dead-man switch" set to activate at that point? Not that it would have saved them, but though.
At least this means they died rapidly and for the most part without pain. Godspeed.
Re: (Score:3, Insightful)
By "Configure the suit for full protection" that means put on the gloves and push down the visor. All of the controls are designed for a unsuited crewmember, the visor gets in the way and requires you to be on your oxygen system. And the oxygen system is pure O2 so you can't keep it running because there will be too much O2 and not enough N2 in the atmosphere of the shuttle.
So, no, there's no possibility for a dead-man's switch in the current design. But it's clearly something necessary in a future desig
Cascading failure (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.
Re: (Score:2)
Consider the SR-71 pilot referenced in the report. He didn't eject, his plane broke up mid-flight, yet he survived. Granted, different thermal environment, but same degree of overpressure.
So, to me, there were things that could have been different that might have resulted in a chance for at least some of the crew to have landed alive.
Sugar-coated death notice (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 [spaceflightnow.com] 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.
Re: (Score:3, Insightful)
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.
Spaceflightnow wouldn't buy into that. I suspect that the incapacitation was due to hypoxia.
Re: (Score:2, Insightful)
Well said, RobertB-DC. Folks such as these people, military special forces, Everest climbers (the originals at least), etc. don't do what they do in hopes of dying a peaceful death. They recognize the likelihood of their fate and run straight to the edge. If they meet their fate, I have to think that they do so with a lot of 'fight' in them. In any case, they are...check that, were true pioneers.
Re: (Score:2, Informative)
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.
The concept there is Time of Useful Consciousness - which is how long a human can remain conscious when exposed to high altitudes. For someone taken from essentially sea level (whatever the shuttle normally is) to 200,000 feet that time is going to be very, very short - probably on the order of seconds. Even at normal fighter altitudes of 40-50,000 feet the TUC is 9-12 seconds, and it is even lower (up to 50% lower) in the case of a rapid decompression, which this almost certainly was.
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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. ... not breathing hasn't been the criteria for "death" since the Middle Ages.
"Incapacitated" isn't a euphemism for dead. Depressurization causes hypoxia, which results in unconsciousness in tens of seconds. They probably died of trauma, but it probably happened after they blacked out.
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not breathing hasn't been the criteria for "death" since the Middle Ages.
Tell that to Cass Elliot.
Re:Sugar-coated death notice (Score:5, 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.
Re:Sugar-coated death notice (Score:5, Interesting)
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;
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.)
Re: (Score:2)
During the incident you mentioned, the pressure differential was one of nine atmospheres. However between atmospheric pressure and vacuum there is only one atmosphere difference - at rest. That is hardly any pressure difference at all. I should think that a more important factor is the actual pressure experienced caused by the shuttle's tremendous speeds - even with a very low static pressure. I for one would not like to be hit in the face by that since it's enough to heat the shuttle's outsides to well ove
What is a survival report? (Score:2, Insightful)
Jokes aside, why is it called "survival report"?
Missing the Point of the Restraint Failure (Score:3, Informative)
The failure of the restraints under this circumstance is only significant in the context of future missions.
It means that future astronauts in a much less dire situation would be killed due to failure of their restraints even if no other mishaps beyond a temporary loss of control occurred. In this particular case, the TFA is pretty clear in pointing out that the crew was either dead or unconscious due to restraint failure which could have been prevented long before catastrophic breakup of the vehicle for which prevention is stated as the only remedy.
A loss of astronaut lives in an event that did not promulgate loss of the vehicle would be politically devastating and need not occur if more attention is paid to this system on future vehicles.
Understatement of the report (Score:2)
"The ground impact without parachute protection generated a very large instantaneous G event."
Yes. Very large. Free fall from 100,000 ft will generally do that.
-S
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No, they would have survived long enough to be killed in said blast.
Seatbelts, the solution to all of life's problems...
Re: (Score:3, Insightful)
an important fact to consider when they build the shuttle's successor.
Does anyone think our government will ever actually accomplish building a successor to the shuttle? Take the best design you can come up with, multiply the cost by 100 and divide the quality by 100. That's what it would end up being.
We, as a society, have lost the ability to manage. The technical know-how may still be there, but the culture of arrested adolescence and unrelenting backstabbing and politics will paralyze the U.S. governm