The potential for fatigue to negatively affect human performance is well established. Concern about this potential in the aviation context extends back decades, with both airlines and pilots agreeing that fatigue is a safety concern. A more recent consideration is whether and how pilot commuting, conducted in a pilot’s off-duty time, may affect fatigue.
The Airline Safety and Federal Aviation Administration Extension Act of 2010 (P.L. 111-216) directed the Federal Aviation Administration (FAA) to contract with the National Academy of Sciences to conduct a study on the effects of commuting on pilot fatigue. The study is intended to inform the development of commuting-related aspects of FAA regulations also specified in the act.
The committee was asked to review available information related to the prevalence and characteristics of pilot commuting; sleep, fatigue, and circadian rhythms; airline and regulatory oversight policies; and pilot and airline practices. Based on this review, the committee will define and discuss several related topics:
- commuting in the context of pilot alertness and fatigue;
- the relationships between the available science on alertness, fatigue, sleep, and circadian rhythms, cognitive and physiological performance, and aviation safety;
- the policy, economic, and regulatory issues that affect pilot commuting;
- the commuting policies of commercial air carriers and, to the extent possible, practices that are supported by the available research; and
- potential next steps, including, to the extent possible, recommendations for regulatory or administrative actions, or further research, by the FAA.
This interim report summarizes the committee’s review to date of the available information. The final report will present a final review, along with the committee’s conclusions and recommendations based on the information available during its deliberations.
Fatigue has multiple interactive sources. The primary ones that may be relevant to pilot commutes include: duration of time awake prior to work, duration of time slept prior to work, quality or restfulness of sleep (i.e., sleep continuity) prior to work, and the biological time (i.e., circadian phase) at which commuting occurs relative to start of work. The duration of time at work (i.e., time on task) is a regulated factor for fatigue mitigation, but it is not regulated relative to commute time since the latter is off-duty time. In the aviation industry, commutes that involve travel across multiple time zones have the potential to exacerbate fatigue associated with commuting, as can chronic restriction of sleep for multiple days prior to commuting.
Commuting by pilots is a common practice that is characterized by tremendous variability. However, comprehensive information on the prevalence or characteristics of commuters is currently unavailable. Although extensive scientific research has been conducted on alertness, fatigue, sleep and circadian rhythms, cognitive and physiological performance, and safety—including research specific to the aviation industry—there is a paucity of information on the nature of commutes or how commuting affects factors that connect sleep and performance.
The committee’s charge does not include a systematic survey of either pilots or airlines, and the specified time and available resources also preclude such a survey. Instead, the committee has requested relevant information from pilot and airline associations, consumer
groups, and individual airlines. That information will be considered, along with further analysis of the relevant research and its implications given what is known about the aviation industry and commuting, in the committee’s final report. To date, the extent and circumstances under which commuting contributes to fatigue are unclear.