Modeling the effects of crew size and crew fatigue on the control of tactical unmanned aerial vehicles (TUAVs)

The field element of the US Army Research Lab (ARL) at Fort Huachuca, Arizona is concerned with the manning required to operate the close-range Tactical Unmanned Aerial Vehicle (TUAV). The operational requirements of the TUAV operators may include extended duty days, reduced crew size and varying shift schedules. These conditions are likely to reduce operator effectiveness due to fatigue. The objective of the study was to analyze how fatigue, crew size, and rotation schedule affect operator workload and performance during the control of a TUAV. The conclusions from executing the models indicate that reducing the number of operators currently recommended for the control of TUAVs results in: 1) 33% more aerial vehicle (AV) mishaps during emergencies, 2) a 13% increase in the time it takes to search for targets, and 3) an 11% decrease in the number of targets detected. Over 400 mission scenario replications of the model were executed allowing statistically reliable predictions to be made of the effect of operator fatigue on performance. Discrete event simulation (DES) models may provide a cost effective means to estimate the impact of human limitations on military systems and highlight performance areas needing attention