ASSESSING PILOT’S FITNESS TO FLY USING FLIGHT PERFORMANCE AND PSYCHOPHYSIOLOGICAL FEATURES

Abstract

Fatigue, diminished vigilance, and burnout reduces a pilot’s flight performance potential and have long been associated with adverse outcomes, including accidents and incidents in aviation. These factors directly affect a pilot’s internal state of fitness to fly. Existing methods for assessing a pilot’s internal fitness state rely on disconnected measures, such as subjective self-reported surveys, physiological features, or standalone flight performance metrics. Individually, these measures do not provide a holistic assessment of a pilot’s capacity to fly safely. In this thesis, I designed, implemented, and validated a Fitness to Fly (F2Y) framework to address this limitation of existing measures. A flight simulator experiment was conducted with 32 pilots performing an RNAV (Area navigation) approach into Mammoth Yosemite Airport, California. Heart rate, pupil diameter, flight performance metrics, and subjective survey responses were collected and integrated within the F2Y framework. The F2Y framework classified the pilot’s internal state of fitness into four F2Y states: Relaxed Controlled, Stressed Controlled, Relaxed Uncontrolled, and Stressed Uncontrolled. Stress was defined by elevated heart rate and pupil diameter, while control was defined by low flight path deviation and a low rate of change of deviation. The F2Y states were classified using data driven thresholds that combined standardized flight performance criteria with individualized physiological baselines. The F2Y score was calculated as the weighted percentage of time spent in each state multiplied by chosen weights. Results demonstrated that the F2Y score captures meaningful patterns in both flight performance and physiological response. Statistically significant differences were observed in both the duration spent within F2Y states and the transitions within them. Findings further revealed a disconnect between subjective fatigue assessments and actual performance outcomes, a gap the F2Y score was explicitly developed to address. By integrating flight performance and physiological data in a statistically robust manner, the F2Y framework provides a holistic, composite, and interpretable metric of pilot fitness to fly. Beyond aviation, this framework has the potential to support broader operational applications, including adaptive human machine teaming systems as well as other safety critical domains where timely assessment of operator fitness is essential.