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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.
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 with idiots who'd sign a petition to outlaw dihydrogen monoxide.
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.
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/
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.
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.
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.
If a job's not worth doing, it's not worth doing right.
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.
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 accidents is that the crew cabin survived for quite a while longer then the vehicle at large. To me, thus suggests there are benefits to be had in figuring out which large structural segments of a crewed spacecraft... even a capsule that can survive uncontrolled re-entry... are going to survive the longest in a catastrophic failure and see if they can last long enough for the crew to bail out. Sure you've just lost the vehicle, but at least you might recover some of the crew.
Insisting that the only way up and down is in a ballistic capsule is throwing the baby out with the bathwater. Something like the Soyuz is fine for now, but there are plenty of ways to make a spaceplane that are not quite as flawed as the shuttle.
Gentoo Sucks
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.
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.
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
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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.
To answer your question, yes. The pressure of the atmosphere is greater than the vapor pressure of the gasses dissolved in your blood. This keeps the gasses from escaping. If you remove that pressure, the gasses escape or "boil" out.
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?"
Life is rarely fair. Cherish the moments when there is a right answer.
Fell apart. Lessee. It had a hole in its wing and survived how many minutes of entry? Then when it lost control it held together for 40 seconds going at Mach 15 or higher? And then the forebody held together for another 40 seconds--going at Mach 15--and then the crew module itself held together for another 10 or twenty seconds? I'll take those engineers any day. In my mind, that's freaking impressive when all factors are considered. And they blame the loss of cabin pressure with lack of restraints as a secondary possibility for the death of the astronauts. Read the CAIB report if you want to determine where to point the finger. And it does point fingers.
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.
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 extremely risky (and never tried) maneuver that isn't necessary with an emergency escape system as Apollo and Soyuz (and the planned Ares I) have it. Such a system was successfully used several times, and it would probably have saved the lives of the Challenger crew.
Am I the only one amazed that being in your seat, with all of your safety harnesses fastened, and your suit/helmet on and sealed, isn't absolutely required during re-entry? Having your seat belts fastened during takeoff/landing is legally required in a junky Cessna 152, much less the multi-billion dollar space shuttle
It was known after the launch that something had hit the wing but an inspection to check the status of the shuttle was not done for some reason.
If they had checked the outer state of shuttle's surface in the ISS they would have surely discovered the damage in the wing.
Repairs attempts could have being tried, or at least the crew, or part of the crew, could have survived in the ISS.
Even the most novel pilots know that it is important to check your aircraft before taking off!
I only have one question in my mind. Did NASA mission management prevented the crew to inspect the shuttle before reentry? If yes, why?
Checking the outer integrity of the shuttle by the crew should be standard procedure before any reentry. If I were crew commander would do it no matter what NASA mission control had to said against it.
Survival/escape alternative using the ISS should be seriously considered. That would be use a good use for that piece of hardware.
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.
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.