Solving Manning Optimization Issues in Ship Acquisition Programs Using Task Network Models

Limitations that humans impose on task execution are rarely integrated into simulations of complex systems, often resulting in loss of outcome fidelity. In this paper we discuss how discrete-event simulation has been used to model the impact of human interactions in U.S. Navy and Coast Guard programs. These models of planned U.S. Navy and U.S. Coast Guard vessels have been used to estimate crew workload, fatigue, as well as overall system performance. In workload measuring applications detailed task networks for teams of individuals conducting ship operations have been modeled over 10 to 14-day scenarios. Predictions of operator workload along with model-generated measures of performance for several manning configurations are used to optimize manning and task allocations for the bridge and operations teams. Another model, the Total Crew Model (TCM) was developed to predict macrolevel crew capabilities. This model predicts the ability of the crew to perform all required duties and estimates fatigue for individual crewmembers. Used in combination, these models have supported HSI professionals in making manning decisions on several levels from crew size and watch team makeup to specific task allocation between watchstanders, and optimal watch rotation and crew schedules for specified mission activity over a sustained period.