Subjective and Objective Evaluation of PIO Tendencies

Unmasking Adverse Pilot Couplings (APC) prior to vehicle entry into service has been a long standing challenge in the Aerospace Industry. APCs, often only exposed through unpredictable or very specific circumstances, have arisen throughout the history of manned powered flight, and have required short-term 'fixes' to ensure system safety. This paper case studies the use of newly created objective and subjective tools for the appraisal of APCs, which have been specifically designed for use during in-flight evaluation. The Phase Aggression Criterion (PAC) is an objective assessment method and is capable of detection during real-time observations. The Adverse Pilot Coupling (APC) scale is a subjective method for the assessment of APCs experienced during completion of closed-loop tasks. Results from the application of both of these tools are presented as well as the correlation between them. The results support the use of both of the tools to improve the understanding of APCs experienced during flight. Furthermore, the application of the tools helps to show the influence of task performance tolerances on the incipience of pilot-vehicle systems to APCs.