The Sleep, Subjective Fatigue, and Sustained Attention of Commercial Airline Pilots during an International Pattern

Abstract

International commercial airline pilots may experience heightened fatigue due to irregular sleep schedules, long duty days, night flying, and multiple time zone changes. Importantly, current commercial airline flight and duty time regulations are based on work/rest factors and not sleep/wake factors. Consequently, the primary aim of the current study was to investigate pilots' amount of sleep, subjective fatigue, and sustained attention before and after international flights. A secondary aim was to determine whether prior sleep and/or duty history predicted pilots' subjective fatigue and sustained attention during the international flights. Nineteen pilots (ten captains, nine first officers; mean age: 47.42+/-7.52 years) participated. Pilots wore wrist activity monitors and completed sleep and duty diaries during a return pattern from Australia to Europe via Asia. The pattern included four flights: Australia-Asia, Asia-Europe, Europe-Asia, and Asia-Australia. Before and after each flight, pilots completed a 5 min PalmPilot-based psychomotor vigilance task (PVT) and self-rated their level of fatigue using the Samn-Perelli Fatigue Checklist. Separate repeated-measures ANOVAs were used to determine the impact of stage of flight and flight sector on the pilots' sleep in the prior 24 h, self-rated fatigue, and PVT mean response speed. Linear mixed model regression analyses were conducted to examine the impact of sleep in the prior 24 h, prior wake, duty length, and flight sector on pilots' self-rated fatigue and sustained attention before and after the international flights. A significant main effect of stage of flight was found for sleep in the prior 24 h, self-rated fatigue, and mean response speed (all p < 0.05). In addition, a significant main effect of flight sector on self-rated fatigue was found (p < .01). The interaction between flight sector and stage of flight was significant for sleep in the prior 24 h and self-rated fatigue (both p < .05). Linear mixed model analyses indicated that sleep in the prior 24 h was a significant predictor of self-rated fatigue and mean response speed after the international flight sectors. Flight sector was also a significant predictor of self-rated fatigue. These findings highlight the importance of sleep and fatigue countermeasures during international patterns. Furthermore, in order to minimize the risk of fatigue, the sleep obtained by pilots should be taken into account in the development of flight and duty time regulations.

Sleep problems and psychosocial work environment among Swedish commercial pilots

“…In earlier studies on sleep quality the captains and first officers were not investigated separately [Eriksen and Å kerstedt, 2006;Lamond et al, 2006;Petrilli et al, 2006;Rosekind et al, 2006]. A possible explanation to our results could be that captains carry a heaver burden of higher responsibilities than first officers.…”

“…There are known increases of physical disease rates among pilots such as melanoma, motor neuron disease, and cataracts [Nicholas et al, 2001], and hypertension [Tomei et al, 2005]. There are reports showing that pilots experience fatigue [BourgeoisBougrine et al, 2003;Jackson and Earl, 2006;Lindgren et al, 2006;Petrilli et al, 2006;Powell et al, 2007], poor mental health [Cooper and Sloan, 1985], mental stress [Raymond, 1988], and sleep problems [Gundel et al, 1995].…”

The psychology of fatigue in patients with multiple sclerosis: A review

“…Such screening batteries might not be appropriate for measuring how fatigue affects cognitive performance. In line with recent evidence in other populations [113][114][115][116][117], it is plausible that fatigue in MS is related to tasks that require sustained attention and executive control. Such tasks are often not assessed in MS patients because they are time consuming and can be enervating for this population.…”

The sensitivity of a palm-based psychomotor vigilance task to severe sleep loss

“…However, several of our field studies have demonstrated that the PDA-PVT is also suitable for use in the field, when conditions are often less than ideal. To date, we have successfully used this device in several work environments, including international flight operations, long-haul train travel, and mining operations (Baulk et al, 2007;Jay, Dawson, & Lamond, 200;Lamond et al, 2006;Petrilli et al, 2006). It is also imp^t to note that although the PDA-PYT may provide anlindication of the fatigue levels associated with a roster, it is simply a sustained attention task, not a test of higher cognitive functions.…”