Flight Simulator Results Comparing Three Aircraft Configurations: Quasi-Static, Flexible and Extended Flexibility

Abstract

Full motion flight simulators are quite commonly used to evaluate handling qualities of an aircraft taking into account its rigid body dynamic model. However, new design, seeking for optimized aerodynamics with high aspect ratios, light and slender wings, has included new issues in handling qualities analysis. In such aircraft, the effect of the aeroelastic modes has a potential to affect its handling qualities characteristics. In this case, these aspects have to be respected in the dynamic model as well as in the flight simulator and the cockpit vibration due to aeroelastic modes must be included in the analysis. In this work the impact of the aircraft flexibility on the handling qualities is investigated. Therefore, an aircraft with significant coupling between rigid body and aeroelastic dynamics is considered. A dynamic model of a flexible aircraft is used, the flight simulator is configured to include the vibration in the cockpit, a dedicated test procedure is proposed, maneuvers with experienced test pilots are executed and the resulting data are analyzed. The pilot evaluation considered the PIO scale. Additionally, to evaluate the aircraft-pilot coupling susceptibility, two additional scales, called Riding Qualities Rating scale (RQR) and Control Inputs Rating Scale (CIR), are introduced. At the end the pilot rates are correlated with the HQ criteria results and remarks made about impact of flexibility on the handling qualities and pilot performance.