System delay in flight simulators impairs performance and increases physiological workload

Delays between user input and the system's reaction in control tasks have been shown to have a detrimental effect on performance. This is often accompanied by increases in self-reported workload. In the current work, we sought to identify physiological measures that correlate with pilot workload in a conceptual aerial vehicle that suffered from varying time delays between control input and vehicle response. For this purpose, we measured the skin conductance and heart rate variability of 8 participants during flight maneuvers in a fixed-base simulator. Participants were instructed to land a vehicle while compensating for roll disturbances under different conditions of system delay. We found that control error and the self-reported workload increased with increasing time delay. Skin conductance and input behavior also reflect corresponding changes. Our results show that physiological measures are sufficiently robust for evaluating the adverse influence of system delays in a conceptual vehicle model.