Closed-loop assessment of flight simulator fidelity

An analytical methodology is presented for the preliminary assessment of piloted flight simulator fidelity. The hypothesis that forms the central theme of the methodology is that many major simulator fidelity problems stem from simulator limitations that adversely affect the pilot's innermost feedback control loop, referred to here as the primary control loop. This loop is the most critical in terms of task performance and the pilot's evaluation of vehicle handling qualities. The proposed methodology, based on a pilot/vehicle analysis of the vehicle and tasks being simulated, has the potential for serving as a tool for the rapid diagnosis of simulator fidelity problems. Selected results from experiments involving both flight test and piloted simulation of a UH-60A rotorcraft in a pair of demanding vertical and lateral hover tasks are used to exercise the methodology and indicate its potential.