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This reminds me of an interview with former NASA astronaut (and current director of the Veteran Administration's National Center for Patient Safety) who related

by adriand 16y ago

This reminds me of an interview with former NASA astronaut (and current director of the Veteran Administration's National Center for Patient Safety) who related that most people don't realize that the astronauts who died in the Challenger accident didn't die in the explosion: > There are still many people that don't understand that the crew of the Challenger didn't die until they hit the water. They were all strapped into their seats in a basically intact crew module; their hearts were still beating when they hit the water. People think they were blown to smithereens, but that's not what happened. http://www.slate.com/blogs/blogs/thewrongstuff/archive/2010/06/28/risky-business-james-bagian-nasa-astronaut-turned-patient-safety-expert-on-being-wrong.aspx http://www.slate.com/blogs/blogs/thewrongstuff/archive/2010/...

yogipatel 16y ago
I forget where I learned this from, but the astronauts were also very likely to be unconscious very soon after the break up of the shuttle. They died when they hit the water, but they probably weren't conscious. Not that that makes it any better.
- pekinb 16y ago
  really? I think that makes it significantly better.
  - ars 16y ago
    I too thought so at first, but after reflection I think it's worse.
- noarchy 16y ago
  Some of them may have been conscious: "At least some of the astronauts were likely alive and briefly conscious after the breakup, as three of the four Personal Egress Air Packs (PEAPs) on the flight deck were found to have been activated. Investigators found their remaining unused air supply roughly consistent with the expected consumption during the 2 minute 45 second post-breakup trajectory." Source: http://en.wikipedia.org/wiki/Space_Shuttle_Challenger_disaster#Cause_and_time_of_death http://en.wikipedia.org/wiki/Space_Shuttle_Challenger_disast...
  - nickff 16y ago
    It was mentioned in the MIT OCW 16.885/ESD35J lecture series that they were likely conscious briefly while still ascending, when they turned on those PEAPs, (after the shuttle had disintegrated); but they were later unconscious, because of the high altitude and low pressures the non-airtight cockpit was subjected to. Source: http://ocw.mit.edu/courses/aeronautics-and-astronautics/16-885j-aircraft-systems-engineering-fall-2005/ http://ocw.mit.edu/courses/aeronautics-and-astronautics/16-8...
- mcritz 16y ago
  In former astronaut Mike Mullane's book Riding Rockets he details how some of the Challenger's controls had been moved from their standard launch positions. NASA tests would later confirm that they could not have been moved by the force of the initial explosion nor the impact with the ocean. At least some of the Challener crew survived the blast, and died in panic.
  - dctoedt 16y ago
    > and died in panic What makes you think that's the case? In The Right Stuff, Tom Wolfe tells of test pilots in out-of-control aircraft who remained firmly in command of themselves, trying A, then B, then whatever they or the ground crew could think of, right up until impact.
juiceandjuice 16y ago
I like this part: It seems that NASA's been willing to accept a fair amount of it, given the tragedies that have bedeviled our space program. NASA has been terrible on this. Not because of how much risk they're willing to accept, and not because they don't do the work to understand it. They always know what the probability of failure is. But, historically at least, they haven't been honest and forthright in taking to the public about it. In the early '80s, before the Challenger accident, they would say—and this is where I think they actually lied, I don't think that's too strong a word—they would say, "Flying the shuttle is like flying a 727 to Disney World." That's absurd. Not only are you more likely to get killed in the shuttle than in an airplane; you're more likely to get killed going up once in the shuttle than if you had flown combat missions for two years in Vietnam. That's a statistical fact, but NASA doesn't make it clear. They might tell the House [of Representatives] that there's a 1.5 percent failure rate, but most Americans don't understand what that means. I mean, 1.5, what is that? Is that a lot? You have to relate it to something that means something to somebody. Otherwise, people have the perception that space flight is safe, and when there's an accident, they're shocked. It's like, "We gotta stop flying." If we want to add additional safeguards because now we're feeling emotional about it, okay, we can do that. But if we're still meeting our design specs for loss, why would we stop flying? I like this approach.
- eliasmacpherson 16y ago
  If you haven't seen it here's R. P. Feynman's Personal observations on the reliability of the Shuttle. I think the reason that additional safeguards were added was not because they begun to feel emotional about it, but rather NASA had underestimated the failure rate in the first instance. The emotional factor is what prompted the investigation. http://science.ksc.nasa.gov/shuttle/missions/51-l/docs/rogers-commission/Appendix-F.txt http://science.ksc.nasa.gov/shuttle/missions/51-l/docs/roger...
  - gvb 16y ago
    Appendix F is a must read. The tl;dr summary is: Engineers at Rocketdyne, the manufacturer, estimate the total probability [of catastrophic failure] as 1/10,000. Engineers at Marshal estimate it as 1/300, while NASA management, to whom these engineers report, claims it is 1/100,000. An independent engineer consulting for NASA thought 1 or 2 per 100 a reasonable estimate. — Personal observations on the reliability of the Shuttle by R.P. Feynman Empirical post script (as of STS-133 24 February 2011) Total launches 132 Failures 2 Successes 130 Failure rate: 1.5% Edit: add opinions: See also http://en.wikipedia.org/wiki/Rogers_Commission_Report#Role_of_Richard_Feynman http://en.wikipedia.org/wiki/Rogers_Commission_Report#Role_o... The reason for appalling and wildly inaccurate estimate of the failure probability is because the failure probability was a top-down "estimate." Someone Important apparently said "the space shuttle needs a reliability of 1/100,000". This mandate was pushed down on all the suppliers. The result was that the probability of failure was divided out onto all the systems, subsystems, subsubsystems... ad nausium all the way down to the bolts. The result was that all the subsystems had reliability numbers that could not be refuted (e.g. bolts at 1/10^12 IIRC), but could not be realistically substantiated either. Unfortunately, some of the probabilities of the major subsystems (SRB and ice damaging the heat shield tiles) were not accurate. The most accurate estimate was the engineer with a lot of experience in extremely complicated systems who gave an experience-based estimate, not a top-down (dictated) numerically derived estimate.

by adriand 16y ago

yogipatel 16y ago

I forget where I learned this from, but the astronauts were also very likely to be unconscious very soon after the break up of the shuttle. They died when they hit the water, but they probably weren't conscious. Not that that makes it any better.

pekinb 16y ago
really? I think that makes it significantly better.
- ars 16y ago
  I too thought so at first, but after reflection I think it's worse.
noarchy 16y ago
Some of them may have been conscious: "At least some of the astronauts were likely alive and briefly conscious after the breakup, as three of the four Personal Egress Air Packs (PEAPs) on the flight deck were found to have been activated. Investigators found their remaining unused air supply roughly consistent with the expected consumption during the 2 minute 45 second post-breakup trajectory." Source: http://en.wikipedia.org/wiki/Space_Shuttle_Challenger_disaster#Cause_and_time_of_death http://en.wikipedia.org/wiki/Space_Shuttle_Challenger_disast...
- nickff 16y ago
  It was mentioned in the MIT OCW 16.885/ESD35J lecture series that they were likely conscious briefly while still ascending, when they turned on those PEAPs, (after the shuttle had disintegrated); but they were later unconscious, because of the high altitude and low pressures the non-airtight cockpit was subjected to. Source: http://ocw.mit.edu/courses/aeronautics-and-astronautics/16-885j-aircraft-systems-engineering-fall-2005/ http://ocw.mit.edu/courses/aeronautics-and-astronautics/16-8...
mcritz 16y ago
In former astronaut Mike Mullane's book Riding Rockets he details how some of the Challenger's controls had been moved from their standard launch positions. NASA tests would later confirm that they could not have been moved by the force of the initial explosion nor the impact with the ocean. At least some of the Challener crew survived the blast, and died in panic.
- dctoedt 16y ago
  > and died in panic What makes you think that's the case? In The Right Stuff, Tom Wolfe tells of test pilots in out-of-control aircraft who remained firmly in command of themselves, trying A, then B, then whatever they or the ground crew could think of, right up until impact.

juiceandjuice 16y ago

I like this part: It seems that NASA's been willing to accept a fair amount of it, given the tragedies that have bedeviled our space program. NASA has been terrible on this. Not because of how much risk they're willing to accept, and not because they don't do the work to understand it. They always know what the probability of failure is. But, historically at least, they haven't been honest and forthright in taking to the public about it. In the early '80s, before the Challenger accident, they would say—and this is where I think they actually lied, I don't think that's too strong a word—they would say, "Flying the shuttle is like flying a 727 to Disney World." That's absurd. Not only are you more likely to get killed in the shuttle than in an airplane; you're more likely to get killed going up once in the shuttle than if you had flown combat missions for two years in Vietnam. That's a statistical fact, but NASA doesn't make it clear. They might tell the House [of Representatives] that there's a 1.5 percent failure rate, but most Americans don't understand what that means. I mean, 1.5, what is that? Is that a lot? You have to relate it to something that means something to somebody. Otherwise, people have the perception that space flight is safe, and when there's an accident, they're shocked. It's like, "We gotta stop flying." If we want to add additional safeguards because now we're feeling emotional about it, okay, we can do that. But if we're still meeting our design specs for loss, why would we stop flying? I like this approach.

eliasmacpherson 16y ago
If you haven't seen it here's R. P. Feynman's Personal observations on the reliability of the Shuttle. I think the reason that additional safeguards were added was not because they begun to feel emotional about it, but rather NASA had underestimated the failure rate in the first instance. The emotional factor is what prompted the investigation. http://science.ksc.nasa.gov/shuttle/missions/51-l/docs/rogers-commission/Appendix-F.txt http://science.ksc.nasa.gov/shuttle/missions/51-l/docs/roger...
- gvb 16y ago
  Appendix F is a must read. The tl;dr summary is: Engineers at Rocketdyne, the manufacturer, estimate the total probability [of catastrophic failure] as 1/10,000. Engineers at Marshal estimate it as 1/300, while NASA management, to whom these engineers report, claims it is 1/100,000. An independent engineer consulting for NASA thought 1 or 2 per 100 a reasonable estimate. — Personal observations on the reliability of the Shuttle by R.P. Feynman Empirical post script (as of STS-133 24 February 2011) Total launches 132 Failures 2 Successes 130 Failure rate: 1.5% Edit: add opinions: See also http://en.wikipedia.org/wiki/Rogers_Commission_Report#Role_of_Richard_Feynman http://en.wikipedia.org/wiki/Rogers_Commission_Report#Role_o... The reason for appalling and wildly inaccurate estimate of the failure probability is because the failure probability was a top-down "estimate." Someone Important apparently said "the space shuttle needs a reliability of 1/100,000". This mandate was pushed down on all the suppliers. The result was that the probability of failure was divided out onto all the systems, subsystems, subsubsystems... ad nausium all the way down to the bolts. The result was that all the subsystems had reliability numbers that could not be refuted (e.g. bolts at 1/10^12 IIRC), but could not be realistically substantiated either. Unfortunately, some of the probabilities of the major subsystems (SRB and ice damaging the heat shield tiles) were not accurate. The most accurate estimate was the engineer with a lot of experience in extremely complicated systems who gave an experience-based estimate, not a top-down (dictated) numerically derived estimate.