- Time perception is extremely important to the understanding, design and use of complex military systems. This experiment focused on differences in time estimation, navigation performance, and monitoring tasks. In a between-subjects experiment, participants navigated through a ground scenario while monitoring a screen and listening to white noise at either 55dBA or 85dBA. Performance data was collected throughout the task for both the navigation and monitoring tasks. Participants also completed the NASA-TLX and the DSSQ-S. Statistical analyses showed that the noise condition did not significantly affect workload, monitoring abilities, task completion and time estimates for the dual task. However, the noise did affect subjective state questionnaires. These results suggest that the dual task was not demanding enough and the stress was not adequate to push participants out of the comfort range and experience a performance decrement.