This study Investigates more dimensions than previous studies simultaneously: pilots’ duty rosters, stress, sleep difficulties, fatigue levels, wellbeing, symptoms of depression, anxiety, and common mental disorders (CMD), and how they are interrelated.


Several scientific studies have confirmed that fatigue can pose a significant risk to flight safety. Other studies reported positive depression screening results for more pilots, compared with the general population.


A cross-sectional online survey was completed by 406 international pilots, who reported their duty rosters of the last two months. Pilots also self-assessed their stress-levels, sleep problems, fatigue, wellbeing, and mental health.


Although pilots were on average rostered for only 60% of maximum legal duty and flight hours, three out of four pilots (76%) reported severe or high fatigue. Every fourth pilot reported considerable sleep difficulties (24%). 18.7% pilots reported positive depression screening results, 8.5% positive anxiety screenings, 7.2% reported significant symptoms of depression and anxiety. Highly significant to high correlations between stress, sleep problems, fatigue, symptoms of depression, anxiety, CMD and well-being were found.


Chronic stress appears to be linked to psychophysiological wear and tear, and was associated with higher levels of fatigue, more sleep disturbances and more impaired mental health. Future research should not only consider fatigue as an immediate threat to aviation safety, but also as a significant threat to pilots’ safety-relevant fitness to fly.


We would like to thank Alvarez IT Solutions for programming the online-survey, IT-security and webhosting and my informal pilot network who supported this research with valuable insights, explanations, check reading, and professional support.



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