Investigators concluded that the
crew was so fatigued that their judgment and decision-making abilities were
impaired and thus contributed to the accident[19].
Although statistics are not kept on the number of plane crashes due
specifically to fatigue, human error is cited as a causal factor in over
70% of fatal passenger flights[18]. Certainly flight crews are as susceptible
to fatigue as any other humans. In August of 1993, a DC-8 crashed while landing
at Guantanamo Bay, Cuba. The figure shows the schedule that the flight crew
was assigned before the crash.Investigators concluded that the
crew was so fatigued that their judgment and decision-making abilities were
impaired and thus contributed to the accident[19].
What about jet lag? Do flight schedules allow crews adequate rest to
compensate for jet lag? In a study by the NASA Ames Research Center, one
laug-haul flight was monitored to study the effect of planned cockpit rest
on flight crews. In 12 days, the crew flew from Seattle to Narita to
Honolulu to Osaka to Honolulu to Narita to Los Angeles to Seoul to
Seattle[20]--not an unusual schedule for long-haul crews.
NASA concluded
that "there were significant positive effects on both performance and
alertness as a result of the cockpit nap"[19].
Federal Aviation Regulation work rules in the U.S. do not explicitly consider pilot duty time, the number of time zones crossed, and whether crew rest preceded flight duty[18]. However, advisory groups have met to give feedback to the F.A.A. concerning flight duty time[19]. Based on recommendations of the NASA Ames study, the F.A.A. has posted "Advisory Circulars" sanctioning the use of cockpit rest for flight crews.
In addition to aviation and highway accidents, transportation accidents occur with trains and ships. Although there were other contributing factors, the famous catastrophic wreck of the Exxon Valdez occurred at 12:04 AM.