Architecture Based Workload Analysis of UAS Multi-Aircraft Control: Implications of Implementation on MQ-1B Predator

An increased demand for use of Unmanned Aircraft Systems (UASs) without commensurate increases in pilot manpower has prompted proposals for simultaneous control of multiple aircraft by a single pilot or Multi-Aircraft Control (MAC). To understand the potential effects of MAC, an IMPRINT Pro, Multi-Resource Theory, pilot workload model was developed from pedigreed system architecture. Feedback from active UAS pilots was used to validate the model and establish a workload saturation threshold value of 60, above which pilots may experience performance degradation over extended periods of time. The model predicts that pilots experience low workload when operating one or two UASs during benign operations, and operate 91% of the time below a workload of 25 without saturation. However, conflict from multi-task overlap builds rapidly when the pilot is required to operate three or more aircraft. The percentage of time over the saturation threshold increases to 21% with four aircraft under benign operating conditions. When dynamic events are introduced the workload becomes unmanageable, with estimates regularly over 100 due to multi-task overlap and communication activities. The analysis indicates the need for techniques and technology to reduce task and communications demands on UAS pilots to effectively implement MAC.