Comparison of Time Delay during In-Flight and Ground Simulation

An in-flight experiment was performed to investigate the effects of time delay on manual flight control and flying qualities. The experiment was conducted using the USAF/FDL variable-stability NT-33A aircraft. Pure time delay was added equally to the pitch and roll flight control system. Evaluation tasks were presented on a head-up display (HUD). Instrument meteorological conditions (IMC) were simulated which limited the visual cues available to the pilot to the 20 degree foveal scene provided by the HUD. The in-flight time delay data were generated with full fidelity, unlimited range of motion cues. Using the same cockpit and a digital aerodynamic simulation, the in-flight experiment was completely replicated as a fixed-based ground simulation. Thus, the effects of extreme conditions in motion cuing (i.e., full motion versus no-motion) were examined for constant visual cuing.