Mitigating fatigue on the flight deck: how is controlled rest used in practice?

Area of Science:

• Aviation Physiology
• Sleep Science
• Occupational Health

Background:

• Pilot fatigue is a significant safety concern in long-haul aviation.
• Controlled Rest (CR) provides pilots with short nap opportunities to mitigate fatigue during flight.

Purpose of the Study:

• To investigate the usage patterns of Controlled Rest (CR) among pilots in a long-haul commercial airline.
• To identify factors influencing the frequency and timing of CR implementation during flights.

Main Methods:

• Utilized actiwatches and a sleep/work diary for data collection over approximately two weeks.
• Analyzed 239 flights, examining CR timing relative to flight schedules and home-base time.
• Employed Pearson correlations and mixed-effects logistic regression to assess demographic and schedule influences on CR use.

Main Results:

• CR was used on 46% of flights, with 80% of attempts successfully achieving sleep (average duration 31.7 minutes).
• CR was significantly more frequent on two-pilot versus multi-pilot flights, return versus outbound legs, nighttime versus daytime flights, and shorter (<10h) versus longer duration flights.
• No significant difference in CR use was found based on travel direction (eastbound vs. westbound).

Conclusions:

• Controlled Rest is a commonly used fatigue countermeasure in this long-haul airline, particularly during specific flight conditions.
• CR is most prevalent on flights with two-pilot crews, shorter durations, and during nighttime, especially on return flights.
• Further research is needed to confirm the generalizability of these CR usage patterns across different airlines.