Pilot In-Flight Sleep During Long-Range and Ultra-Long Range Commercial Airline Flights.

Area of Science:

• Aviation safety and human factors research.
• Sleep science and chronobiology.

Background:

• Pilot fatigue is a significant safety concern in commercial aviation, particularly on long-range (LR) and ultra-long-range (ULR) flights.
• In-flight rest breaks are a key strategy to mitigate pilot fatigue, with sleep quality directly impacting performance.

Purpose of the Study:

• To quantify total in-flight sleep (TIFS) in commercial pilots on LR and ULR routes.
• To characterize the types and efficiency of in-flight rest schemes used by pilots.
• To determine how rest scheme complexity affects sleep opportunity and efficiency.

Main Methods:

• Data collected from 231 pilots across 3 LR and 5 ULR routes between 2015 and 2019.
• Utilized a combination of actigraphy and pilot logbooks to record in-flight sleep.
• Analyzed over 1200 flight duty periods, considering flight direction and crew configurations.

Main Results:

• Average TIFS ranged from 3.4 to 5.2 hours across all routes, with some ULR pilots exceeding 8 hours.
• Simple two- or three-break rest schemes were predominantly used, while complex four-break schemes were rare and confined to the longest ULR routes.
• Complex rest schemes showed slightly lower efficiency and did not yield greater TIFS compared to simple schemes on the same routes.

Conclusions:

• Commercial flight crews are obtaining more in-flight sleep than previously documented on similar routes.
• Simple rest schemes are more efficient and provide comparable sleep opportunities to complex schemes.
• Optimizing rest schedules with simpler schemes may enhance pilot performance and safety on long-duration flights.