Pilots’ eyes on the horizon: is one pair enough?

Early commercial airplanes typically had five crew members on board. Today, this number has been reduced to two: a captain and a first officer. Advances in technology and flight automation have transformed the roles of pilots, leading to investigations into the possibility of further reducing crew sizes to just one pilot per flight. Proponents of this idea argue that single-pilot operations are feasible with the right technological and regulatory support. However, skeptics express concerns about the safety and reliability of increased automation. 

Researchers from Hong Kong and Singapore universities, led by principal author Qinbiao Li, have collaborated to study the differences in the captain’s performance in dual-pilot and single-pilot scenarios. Their research focuses on how a captain’s brain activity and visual behavior change when flying solo, especially during emergencies. 

The study involved twenty pilots who each flew a flight simulator from Hong Kong Airport to Guangzhou Baiyun Airport, facing emergencies such as engine failures, stalls, landing gear malfunctions, and engine fires, both with and without the assistance of a first officer. The scientists measured the pilots’ brain activity using electroencephalogram (EEG) and tracked their eye movements with
Tobii Pro Glasses 3. 

The findings of the study include: 

• Cerebral cortical activity, particularly β and θ waves, was significantly stronger in single-pilot scenarios, especially during emergencies. Higher levels of β and θ waves are associated with increased mental demands. 
• Single pilots focused less on the primary display while spending more time scanning the secondary displays, pedestals, and overhead panels during emergencies.  
• Single pilots’ gaze on cockpit instruments was more dispersed than pilots flying with a co-pilot. 
• In scenarios like engine stalls, single pilots’ mental efforts were intensely focused on resolving the issue. The authors note that sustaining such a mentally demanding state could lead to mental fatigue over time. 
• Flying solo, pilots reported experiencing higher workloads, reduced safety, and feeling less confident in handling emergencies. 

This research represents an initial step toward assessing the viability of single-pilot operations from a human-centered perspective. The study’s insights could contribute to developing intelligent flight systems that recognize a pilot’s physiological state—such as cognitive overload, loss of situational awareness, or fatigue—and provide the necessary support to ensure safer air transportation. 

Cited publication

Li, Q., Chen, C.-H., Ng, K. K. H., Yuan, X., and Yiu, C. Y. (2024). Single-pilot operations in commercial flight: Effects on neural activity and visual behaviour under abnormalities and emergencies. Chinese Journal of Aeronautics.