Addressing the challenge of strong aerodynamic interference in multi-rotor electric vertical take-off and landing (eV-TOL) aircraft while existing methods cannot quickly and efficiently analyze its impact on flight performance and flight quality, an Urban Air Mobility (UAM) flight dynamics model integrated with multi-rotor aerodynamic interference has been developed. First, by combining classical vortex theory and dynamic inflow model, a dynamic inflow model suitable for flight dynamics analysis of multirotor is established, accounting for the effects of coupling between rotor flapping and rigid-body motion, thus forming a flight dynamics model that incorporates multirotor aerodynamic inter-ference. Then, the accuracy of this model is validated through comparison with data from international literature, and the impact of multirotor aerodynamic interference on the equilibrium characteristics and required power characteris-tics of the aircraft is analyzed. Finally, a small-disturbance linearized model is used to study the effect of multirotor aerodynamic interference on the stability of the aircraft. The results show that aerodynamic interference between rotors mainly affects the flight performance and handling qualities of the aircraft in low- to medium-speed flight con-ditions. Aerodynamic interference slightly reduces the required power of the front rotors while significantly increas-ing that of the rear rotors, substantially altering the aircraft's longitudinal control characteristics. Multirotor aerody-namic interference significantly enhances the speed and yaw static stability during hover/low-speed flight and im-proves the lateral static stability in medium-speed flight; however, it causes the angle-of-attack static stability to be-come unstable, which, in turn, degrades the dynamic stability of the heave mode and spiral mode.
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