We saw earlier that acute fatigue can be mitigated by sleep. The crew do attempt short-term mitigations such as the use of caffeine (coffee or energy drinks), taking a leg stretch out of the seat and taking a break that does not include a nap. Napping on the flight deck is known as controlled rest (CR). In an online survey of 218 pilots, Stait (2019) found that 69% of respondents had used CR. Many airlines make provision for crews to take naps in flight, and the mitigation is bounded by quite strict rules. The first problem we find is that the actual rate of CR in aviation is not really understood. In one LOSA, we looked at the actual incidence of CR. During the study period, nine instances of CR were taken, representing 6% of possible flights. We found that if the captain took rest then the FO might, but FOs never took rest if the captain had not already done so. So, it seems that there is a social dynamic that might inhibit FOs from taking rest even if they needed it. Resting on the flight deck is just one-way crew can tactically manage fatigue (recognising that the provision is not always used appropriately). Stait also reported that 65% of the crew made use of the autopilot as mitigation, and 33% had elected not to act as the pilot flying because of tiredness. These are examples of using technology or procedures to cope with fatigue in the workplace.
If we now look at who takes CR, we see that there are, in fact, three categories. The intended users of CR are those who find, at that moment, they are in need of rest. The assumption is that the crew member reported fit for duty but has experienced such a rapid onset of fatigue that they need to take action. However, there are two other groups that take advantage of the rules: those who fail to prepare appropriately for duty and use CR to manage their lifestyle, and those suffering from chronic fatigue and are unable to recover between shifts and so need to rest in flight.
Chronic and psychological fatigue typically need more than simply additional sleep to effect a recovery. It has long been recognised that humans have a tendency to resort to symptom-directed coping to mitigate stress, which includes using alcohol as a distraction. Sleep medication can also be used as a stop-gap fatigue management tactic. In a study of 435 Portuguese pilots (Reis et al., 2016), the authors found that the percentage of individuals taking sleep medication or using alcohol as a sleep aid was
FIGURE 4.7 Use of alcohol and sleep medication.
very low (1.4% for each). There was a positive significant relationship between the use of alcohol and medication and sleep complaints (measured using the JSQ questionnaire), but not with fatigue or daytime sleepiness. The sample comprised pilots mainly involved in short and medium-haul flying (72%), and mitigations seemed to be responses to disrupted sleep patterns. Stait (2019) found that 6% of respondents in her survey reported frequent (>3 times a week) use of sleep medication. In my survey, 305 pilots provided data on their use of alcohol and medication. The results are shown in Figure 4.7. Of interest here is that it is the intermediate group that seems to be resorting to aids to sleep, the exception being the (relatively) moderate use of alcohol by the burnout risk group.
It should come as no surprise that the most fatigued pilots feel that they do not recover sufficiently between work periods, have poor sleep quality and experience serious levels of daytime sleepiness. However, the data suggest that all pilots suffer from inadequate recovery, and even the least fatigued group has individuals who suffer from sleep problems. Of particular interest is the 40% of pilots in the sample comprising the moderate fatigue group. The data suggest that, rather than occupying the middle ground, they tend more towards the highest fatigued group in terms of characteristics. If we look at their attempts at mitigation, it seems that the moderately fatigued pilots are most likely to resort to alcohol, initially. Alcohol consumption within 3 hours prior to sleep actually degrades the sleep experience: it is counter-productive as fatigue mitigation. Once physiological fatigue reaches a certain level, it seems that a self-sustaining feedback cycle is set up that, ultimately, will lead to long-term health effects.
Fatigue and Pilot Health
Pilots in my survey were asked to complete a standard health status questionnaire, the SF-12 (Ware, Kosinski & Keller, 1996). The survey generates a physical and a mental health score. The pilots all had access to private medical insurance and were subject to periodic medical checks in order to retain their license to fly. Therefore, it should be expected that the group would be in good physical health. A score of
<50% is indicative of poor health and indeed, only 7.5% of the pilots score less than 50% on the physical scale. On the mental health scale, 29.2% of pilots scored less than 50%, but Figure. 4.8 reveals a markedly different distribution of scores on the two scales. As we would expect, the group w'as heavily skewed towards the upper end of the scale for physical health but the mental health scores follow' a more normal distribution. The respondents also completed the FSS, and w'hen we factor in chronic fatigue, the effect is quite stark. Figure 4.9 shows the percentage of pilots in each fatigue category scoring more than 50% on each component scale and, thus, reflecting a better health state. Pilots in the poorest fatigue group still make up the majority of those scoring lowest for both mental and physical health.
Fatigue, then, has a significant impact on both physical and mental health. In Figure 4.5, w'e saw that emotional demands and work-home conflict were factors in
FIGURE 4.8 Pilot physical and mental health.
FIGURE 4.9 Pilots’ health and fatigue.
the JD-R model. The model operationalises the concept of stress as being a dissonance between expectations and capability but also has exhaustion as an output. Job demands are defined as those physical, psychological, social or organisational aspects of the job that require sustained physical and/ or psychological effort. Job resources are those physical, psychological, social or organisational aspects of the job that are functional in achieving work goals, reducing job demands and the associated physiological and psychological costs. They can also stimulate personal growth, learning, and development. The findings for the relationship between fatigue and mental health suggest that a pilot’s capacity to cope with emotional demands will be diminished. Effective support from friends and family is considered an important factor in stress coping, but, again, high levels of fatigue appear to be associated with degraded WLB.
Sustained inadequate recovery can lead to ‘burnout’, a concept that describes an extreme condition often associated with a degraded health state. There is no agreement about the specific condition we call ‘burnout’, its development and the way it presents in terms of symptoms. Nonetheless, it remains a useful indicator of a problem. In a study of 1147 UK airline pilots using the OLBI, 20% of the sample reported clinical levels of burnout (Demerouti et al., 2019). A benchmarking study of 13,000 employees from several different occupations suggests that 4% had the symptoms of burnout (Bakker et al., 2000). We saw earlier that in my study of 80 line pilots 10.71% scored sufficiently high on the OLBI to be classed as burnout candidates. The Germanwings crash on 24 March 2015 (BEA, 2016), in which the mental state of the FO appears to have been a cause, has focussed more attention on mental health issues in aviation. In one survey of 328 pilots (Aljurf et al., 2017), 34.5% scored above the cut-off on a measure of depression. A larger survey of 1848 pilots from the United States of America (Wu et al., 2016) found that 12.6% of respondents showed evidence of mental health issues. Of interest, symptoms of depression were higher in pilots using sleep medication more than three times a week (33.3%). In Figure 4.7, a small percentage of pilots in the intermediate and burnout risk group fell into that category. O’Hagan et al. (2017) found that pilots who spent long hours on duty per week were twice as likely to report feeling depressed or anxious.
The arc traced in this chapter ultimately arrives at medical impairment, either in terms of degraded general health or a psychiatric condition. I think that it is important to recognise that among ‘rested’ individuals and those living with permanent tiredness, there is a hinterland of pilots struggling to cope with the demands of life but are not yet at the point of suffering a collapse in their mental health. They appear to be more reliant on alcohol and sleep medication to arrest their worsening condition than the other groups. Demerouti makes the point that ‘the job of a pilot is not only detrimental for health-related outcomes, i.e. exhaustion (because of high or badly designed job demands) but also for motivation due to lack of job resources’ (Demerouti et al., 2019).