Roll performance assessment of a light aircraft: Flight tests and flight simulation

This paper deals with the assessment of roll performance of a light aircraft through several flight tests and flight simulations. The general problem of a reliable evaluation of aircraft roll performance is first discussed, including the estimation of the aerodynamic derivatives that mainly influence the airplane rolling characteristics. Next, the results of extensive flight test activities on a two-seats Tecnam P92 light aircraft are presented. The attentive analysis of many roll maneuvers performed at different flight speeds and with various aileron maximum deflections has shown unexpected good roll performance for this non-aerobatic aircraft and has been extremely useful to derive the aileron efficiency factor in non-linear conditions (high aileron deflections). Flight data have been used to extract the main aerodynamic derivatives involved and to implement an accurate flight simulation model of the aircraft. Both 1-DoF and 6-DoF Flight simulations have been used in the first part of this research to select an appropriate matrix of test conditions. Finally, when the key lateral aerodynamic derivatives were estimated from flight experiments, the resulting flight simulations have shown a very good agreement with measured time histories.