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According to Daylight Savings Time and Traffic Accidents N Engl J Med 1996; 334:924-925

Major disasters, including the nuclear accident at Chernobyl, the Exxon Valdez oil spill, and the destruction of the space shuttle Challenger, have been linked to insufficient sleep, disrupted circadian rhythms, or both on the part of involved supervisors and staff.

Is this really true?

  • Did you want to know if there is truly a link between the two, or merely if someone somewhere may have (rightly or wrongly) made such a link? – T.E.D. Nov 15 '16 at 15:27
  • @T.E.D. I want to know the truth. If you have more info to add, then add an answer. – DavePhD Nov 15 '16 at 15:44
  • @DavePhD The truth about what? Whether Chernobyl was caused by a humand error done because the guy did sleep enough that night? Truth about whether insufficient sleep disrupts circadian rhythms? – Bakuriu Nov 15 '16 at 16:22
  • @Bakuriu Just the Challenger. I'm limiting the question to just that accident. – DavePhD Nov 15 '16 at 16:27
  • Whilst lack of sleep may have played a role I suspect it would have been a minor one at most. Given the pressure applied by NASA to Thiokol to get them to withdraw their recommendation to not launch combined with their attempts to justify what was an obviously ridiculous decision to launch after the fact suggests that the whole management style at NASA had primed the pumps for that accident to happen. Given that the same managerial issues seem to have been a big factor in the loss of Columbia as well I suspect management culture was the prime candidate for Challenger's loss – GordonM Mar 23 '18 at 11:27
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On the headline question

Has “the destruction of the space shuttle Challenger… been linked to insufficient sleep”

There probably was a link, as it was important enough included in the Rogers report. As was reported by NASA:

The Rogers Commission Human Factors Findings stated, "The willingness of NASA employees in general to work excessive hours, while admirable, raises serious questions when it jeopardizes job performance, particularly when critical management decisions are at stake."
source: NASA: To sleep or not to sleep

The cause of the accident itself is well known and was, put simply, a failure in the joint between the two lower segments of the right Solid Rocket Motor.

The relevant part of the Rogers Report for this question is human factor analysis which states:

Other studies have demonstrated that night work and shift changes produce sleep loss and fatigue by disrupting workers' Circadian rhythms.

For which that line cites:

Akerstedt, T., "Adjustment of Physiological Circadian Rhythms and the Sleep-Wake Cycle to Shiftwork." In S. Folkard and T.H. Monk (Eds.), Hours of Work, New York: Wiley, 1985, pages 185-197.

The report goes on

One group of such workers are the Morton Thiokol employees who typically work 12-hour shifts, either 3:00 p.m. to 3:00 a.m. or 3:00 a.m. to 3:00 p.m., from two to seven days (mean = 4.5 days) in a row while performing the stacking of the Solid Rocket Boosters. Both these extended work schedules disrupt normal sleep patterns by starting or ending at about the usual midpoint of night sleep, thereby producing substantial sleep loss. The occurrence of lengthened workdays of 12 to 16 hours in the preceding four case histories would also disrupt sleep by interrupting the worker's adjustment to his current shift schedule.

  • 6
    I may not be reading this correctly, but is there any link established in the report? (which to me seems to imply causation, not merely the fact that there was sleep issues) – user5341 Nov 14 '16 at 17:22
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    @user5341 it's an interesting point. I read many accident reports - usually to do with aviation, but they are not dissimilar to this report. When it comes to human factors, there is rarely one pinpointable "cause", and more often than not a chain reaction of events which led to an accident/incident. In this case I would say that the sleep habits of the NASA staff, especially those responsible for the SRB's, could have contributed to the accident. It was not, by any means the "cause" of the accident though. The question asked if there was "a link" and the answer is, "yes, probably". – Jamiec Nov 14 '16 at 17:28
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    If you skip to the bottom of the report, you'll see that failure of the joint was not a root cause. The joint failed because the temperature on the morning of the launch was too low: 36 F. 61 F was considered the minimum temperature by the engineering team to avoid damage to the O-rings. As I understand it, the engineers desperately tried to get the launch postponed but the presentation was so obtuse, no one could figure out what they were saying. Perhaps sleep was a factor in both the presentation and how it was no understood. – JimmyJames Nov 14 '16 at 17:31
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    @PaulDraper - I'm afraid you are right. It's a great answer, by the way - I would add the explicit note that there's no actual proof/causation just for clarity, but it's definitely a solid well researched answer. – user5341 Nov 14 '16 at 17:56
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    The point of failure is very different from the cause of an event. If that were the case, every autopsy, including those of these astronauts, would conclude that death occured due to lack of oxygenated blood to the brain. It doesn't really adequately explain the circumstances that gave rise to the situation in the first place. If you're going to backtrack the chain of events, it seem disingenuous to stop at the O-rings. – J... Nov 14 '16 at 19:01

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