Fatigue, emotion and cognitive performance in simulated long-duration single-piloted flight missions

Background: Fatigue of air force pilots has become an increasing concern due to changes in mission characteristics. In the current study we investigated fatigue, emotions and cognitive performance in a simulated 11-hours mission in the 39 Gripen fighter aircraft. Methods: A total of twelve subjects were evaluated in a high-fidelity dynamic flight simulator for 12 consecutive hours. Perceived fatigue was measured by the Samn-Perelli Fatigue Index (SPFI). Emotions were assessed with the Circumplex Affect Space. Cognitive performance was assessed by five cognitive tasks. Results: Significant increase in self-reported fatigue, general decrease in two positive emotional states, as well increase of one negative emotional state occurred after approximately seven hours into the mission. Self-reported fatigue negatively correlated with enthusiasm and cheerfulness (r’= -0.75; -0.49, respectively) and positively correlated with boredom and gloominess (r’ = -0.61; r’ = -0.30, respectively). Response time in the low-order task negatively correlated with enthusiasm, cheerfulness and calmness (r’= - 0.44; r’= - 0.41; r’= - 0.37, respectively) and positively correlated with boredom and anxiousness (r’ = 0.37; r’ = 0.28, respectively). Mission duration had an adverse impact on emotions in these environmental conditions, particularly after seven hours. Discussion: These results contribute to the understanding of fatigue development in general and of emotion-cognition relationships. These findings emphasize that both emotional states and the type of cognitive tasks to be performed should be considered for planning long-duration missions in single-piloted fighter aircrafts as to increase the probability of missions’ success. Keywords: military missions, fighter aircraft, objective and subjective pilot performanc