Abstract
Mental workload assessments are used as a component of the test and evaluation of aviation systems. To be acceptable, mental workload should not be excessively high. Conceptually, it should be below a critical redline level. Previous research identified 40 ± 10 as a redline range for the Subjective Workload Assessment Technique (SWAT) primarily based on laboratory task batteries (Reid & Colle, 1988). Using an air-to-ground combat task with an objective performance criterion, we estimated a SWAT redline and found it to be within the original recommended range. We discuss implications and limitations of the approach.