A Comparison Of Serial And Parallel Processing Simulation Models Of Pilot Workload

This paper discusses and evaluates several options for modeling a pilot while he performs normal cockpit duties. Using a queueing analogy, with the pilot modeled as the server and the pilot's tasks as customers, two discrete-event simulation models were developed. The main issue examined was the relative accuracy of a model which processes tasks in series versus one which processes tasks in parallel. Each of these models employed a priority system with preemption. The serial model processed one task at a time while the number of tasks that could be processed simultaneously in the parallel model was dependent on the mix of tasks currently demanding the pilot's resources. Three different measures from the simulation models were evaluated as workload surrogates: pilot idle time, task interrruption rate, and the simulataneous task rate. Workload model predictions were validated by comparison to workload measurements taken under identical conditions in a high-fidelity flight simulator. The models' validation process suggests that the technique has merit and continued investigation is warranted.