Cyclogyro is a kind of new UAV propelled by cycloidal propellers with extremely low noise, high efficiency and high maneuverability. Flight test of roll step-input shows that the cyclogyro suffers from poor stability. The dynamic model of cyclogyro was established and the simulation was done to figure out how the configuration parameters affect the rolling stability. Simulation results show that the gyroscopic effect of cycloidal propellers leads to the coupling of the moments about three axis,which deterio...