and Capelle, 1987). Not only are hours-of-service violators more likely to speed or drive longer hours when given unrealistic driving times, but they are also more likely to report having fallen asleep at the wheel (Braver et al., 1992). Higher crash rates have also been reported by hours-of-service violators (Braver et al., 1992; Jones and Stein, 1987).

A notice of proposed rulemaking to update the Hours of Service regulations was issued in May 2000, generating over 50,000 comments and significant controversy (NTSB, 2002b). To date, none of the following changes have been adopted: (1) increase the on-duty/off-duty cycle to a normal 24-hour work cycle; (2) increase time off to allow sufficient time for 7 to 8 hours of sleep; (3) require mandatory “weekend” recovery periods consisting of at least 2 nights of recovery sleep to enable drivers to resume baseline levels of sleep structure and waking performance and alertness; (4) address the effects of operations between midnight and 6:00 a.m., requiring off-duty periods that enable restorative sleep by including two consecutive periods between these hours; (5) allow “weekends” of sufficient length to ensure safety and provide adequate protection for driver health and safety; and (6) increase operational flexibility by offering a menu of hours-of-service options customized to different major or distinct operational segments while maintaining an appropriate level of safety (Federal Motor Carrier Safety Administration, 1999).

Aviation Industry

Although Charles Lindbergh was not the first pilot to experience the effects of fatigue, his description of fighting fatigue during his 1927 transatlantic flight graphically illustrates the dangers of tired pilots:

My mind clicks on and off. I try letting one eyelid close at a time while I prop the other with my will. But the effort is too much, sleep is winning, my whole body argues dully that nothing, nothing life can attain is quite so desirable as sleep. My mind is loosing resolution and control. (Printup, 2000)

Lindbergh landed safely near Paris after flying for 33.5 hours. Others have not been so lucky, either flying across the Atlantic or within the borders of the United States. The U.S. Air Mail Service was founded in 1918, 15 years after the Wright brothers’ initial flight. Accident rates were extremely high: 31 of the original 40 Air Service pilots died in work-related airplane crashes between 1918 and 1921 (Leape, 1994). Lack of attention to safety and “efforts to meet delivery schedules in all kinds of weather” were believed to be the cause of this extraordinarily high accident rate (Leape, 1994). By 1926, the aviation industry, worried that the airplane would not reach its full commercial value without federal action to improve



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