NRC Study on Pilot Commuting Calls for More Study

 - July 28, 2011, 8:40 AM

Commuting practices among airline pilots could potentially contribute to fatigue, and because fatigue can reduce performance, pilots, airlines and the FAA should take steps to reduce the likelihood that commuting will pose a safety risk, according to a new report produced by the National Research Council (NRC). However, too little data exists to determine the extent to which commuting poses a safety risk or whether the FAA should regulate the practice, said the NRC. It concluded that the FAA should support a new study to gather data on how commuting practices can relate to risk factors for fatigue, however.

The report offers guidance for how pilots should manage their sleep and wake time to avoid fatigue levels that could affect performance. Specifically, pilots should plan their commutes and other pre-duty activities to allow for no more than about 16 hours of time awake by the end of a duty day, and they should endeavor to sleep for at least six hours before reporting for duty, said the report.

Airlines should collect more data on their pilots’ commuting practices and educate pilots about potentially fatiguing effects of commuting, said the committee that wrote the report. These companies should also consider policies to help pilots plan predictable, non-fatiguing commutes and minimize negative consequences when disrupted commutes lead to fatigue. 

“Some commutes have the potential to contribute to fatigue in pilots, and fatigue can pose a safety risk, but at this point we simply don’t know very much about actual pilots’ commuting practices,” said committee chair Clint Oster, a professor in the School of Public and Environmental Affairs at Indiana University, Bloomington. “Airlines and the FAA should gather more information on pilots’ commutes, and also work with pilots to lower the likelihood that fatigue from commuting will be a safety risk.”

Fatigue Risks of Commuting

Congress asked for the report following the Feb. 12, 2009, fatal crash of a Colgan Air Bombardier Q400 outside Buffalo, N.Y. Critically, although the NTSB said fatigue “likely” impaired the pilots’ performance, it would not venture a judgment on the extent of the impairment and the degree to which fatigue contributed to the deficiencies exhibited during the flight. It did, however, fault the pilots for failing to manage their off-duty time and effectively use available rest periods and appropriate facilities before reporting to work. It also faulted Colgan Air for failing to “proactively address” pilot fatigue hazards associated with operations at a predominantly commuter base–in this case, Newark Liberty International Airport.

Records indicate that on the day of the accident, the flight’s captain, Marvin Renslow, logged into the company’s crew scheduling computer system at 3:10 a.m., and that the first officer, Rebecca Shaw, commuted to Newark on an overnight flight and had sent and received text messages on the day of the accident. Colgan had scheduled the crew to report at 1:30 p.m. on the day of the accident, but high wind at the airport forced the cancellation of the first two flights of the day. Schedules called for Flight 3407 to take off at 7:45 p.m. Although ground crew pushed the airplane back from the gate at 7:45, the crew did not receive taxi clearance until 8:30 p.m., and the tower cleared the flight for takeoff at 9:18 p.m.

During a February 2 Board meeting last year, NTSB human performance investigator Dr. Evan Byrne noted that although Renslow stayed overnight in the crew room at Newark and the accident occurred during his normal bedtime, just after 10:17 p.m., neither he nor first officer Shaw showed degraded performance throughout the flight, and that the errors they did commit didn’t necessarily point to fatigue. Byrne concluded that although the pilots likely did experience some fatigue, this particular case didn’t warrant any indictment on current flight- and duty-time rules, nor did it invalidate the practice of commuting per se. In fact, most of Colgan’s pilots who fly from EWR commute.

However, noted Byrne, the airline did not discourage same-day commuting and did not enforce its policy against sleeping in crew rooms. In one of the NTSB’s 25 recommendations stemming from the investigation, the Safety Board called for a requirement that all Part 121, 135 and 91K operators “address fatigue risks associated with commuting, including identifying pilots who commute, establishing policies and guidance to mitigate fatigue risks for commuting pilots, using scheduling practices to minimize opportunities for fatigue in commuting pilots and developing or identifying rest facilities for commuting pilots.”

Still, the recent NRC report concluded that not enough evidence exists to determine the extent to which pilot commuting in general has posed a safety risk, partly because researchers know so little about specific commuting practices and partly because the existing safety checks, balances and redundancies in the aviation system might mitigate the consequences of pilot fatigue.

The committee could find no “systematic” data on pilots’ commuting practices, such as the distance traveled or modes of transportation used, said the report. Nor could it find any such data on the duration or quality of pilots’ sleep before or during their commutes. 

Defining what constitutes a fatiguing commute based on time or distance proves difficult, the committee added, because the length of commute does not necessarily determine whether a pilot reports well rested and fit for duty. A pilot might commute a long distance, for example, but arrive in time to get adequate sleep at a local accommodation before flying. Conversely, a pilot could live close to the airport from which he or she flies, sleep poorly for any number of reasons, and report to duty fatigued.  Given the nature of flight scheduling, most pilots do not commute daily; in fact, some commute only a few times a month.

“At this time there is not enough data to support regulation of pilot commuting, and additional information will be needed to determine the extent to which commuting is linked to fatigue and whether a regulatory approach ultimately would be appropriate,” the committee said. “The FAA should fund a study of the relationships between commuting distances and primary risk factors for fatigue, such as sleep quantity in the 48 hours before the end of duty on each day of the trip. The study should include a large random sample of pilots from multiple companies representing major parts of the industry, and it should collect objective data on sleep and waking time using reliable technology as well as sleep-wake diaries.”