Differential Sensitivity of Using Simulators Versus Actual Aircraft to Evaluate the Effects of a Stimulant Medication on Aviator Performance

The comparability of simulator versus aircraft results was examined with a quasi-experimental approach. Flight data from 10 UH-60 pilots, who flew a helicopter simulator, and 10 pilots who flew an aircraft were pooled to assess the influence of the flight platform on Dexedrine® versus placebo effects in two 40-hr periods of sustained wakefulness. Overall, performance under Dexedrine® was better than performance under placebo, but consistent stimulant and fatigue effects were observed across both flight platforms less than one third of the time. Sensitivity was lower in the aircraft, likely because of differences due to environmental influences (weather, temperature, and turbulence) and other factors (radio traffic and, possibly, anxieties about safety). Thus, simulator studies, although desirable in terms of cost and safety, may overestimate the impact of stressors (e.g., fatigue) as well as the potential benefits from fatigue countermeasures (e.g., Dexedrine®). Conversely, in-flight studies may underestimate these types of performance effects. As a result, caution is advised when attempting to generalize findings from one flight platform to the other.