Identifying Military Rotary-Wing Pilots at Increased Risk of Fatigue Using Biomathematical Modeling

A study of British military rotary-wing pilots was conducted using actigraphy-driven fatigue modeling to identify groups of pilots at increased risk of fatigue.

Pilots were recruited across the three military services of the United Kingdom. Objective fatigue was predicted using wearable actigraphy and the Sleep Activity Fatigue Task Effectiveness (SAFTE) fatigue model. Subjective data were collected from daily questionnaires, including descriptions of workplace activities and subjective assessments of the subjects' fatigue levels, using Samn-Perelli scores. An assessment was then made of the relationship between their workplace activities and their subjective and objective fatigue levels.

There were 38 men and 2 women recruited. The mean age was 36.4 yr (SD ± 6.5, range 26-52 yr). A total of 200 flights were undertaken, with a mean flight time of 156 min (±77.1, range 15-480). SAFTE scores were shown to decline for night-flying, declining strongly after 22:00. Pilots deployed on exercise were more likely to be subjectively and objectively fatigued, regardless of the timing of their flights. Pilots cohabiting with infants under 1 yr of age were more likely to suffer fatigue decrements than those who did not. The data suggest that inexperienced pilots find their flights more subjectively fatiguing than their instructors, but more work is needed in this domain.

Biomathematical fatigue modeling such as SAFTE has a role in military rotary-wing aviation. Consideration should be given to its use in night-flying, flights undertaken when deployed, and for those cohabiting with infants. Pelham A, Van Tongeren M, Arnold H, Cocco P. Identifying military rotary-wing pilots at increased risk of fatigue using biomathematical modeling. Aerosp Med Hum Perform. 2025; 96(12):1043-1049.