How does a pilot's mental state and cognitive abilities change when in single pilot operations during a flight emergency?

The captain's cognitive activity, like situation awareness (SA) variations, in single-pilot operation (SPO) should differ from that during two-crew operation (TCO). This study aims to reveal the pilot's performance and cognitive changes from the neurophysiological perspective during SPO. We conducted an experiment with a stable flight from the VHHH to the ZGGG, with several events taking place mid-flight to increase the pilot's task load. An EEG and a glasses-based eye-tracker are deployed to record the neurophysiological data throughout the experiment. A questionnaire and observation are utilised to evaluate pilot's performance, and a tablet pc presents SA probes to investigate pilot's SA at specific positions. The pilot's response and reaction time to SA probes is an objective indicator to measure their SA variations during SPO and TCO. Subsequently, a neuro-physiological pattern related to cognitive activity during the emergency events are revealed. It is expected that flight performance will be different between two scenarios based on the observation and post-experimental subjective findings. The SA is a critical parameter for maintaining good human performance while operating an aircraft, as they affect the probability of a dangerous flight ]. During SPO, detecting single-pilot cognition incapacities, like low SA, is important to ensure aviation safety. The current study is original in promoting SPO development, which could be used to classify single- pilot's undesirable performance as a 'key' to open system collaboration measures.