Abstract: Aiming at the difficulties in flutter design due to uncertainties of structural parameters for the initial stage of aircraft design project, the research on the aircraft flutter rapid analysis method in the planning stage is carried out. The fictitious mass method is applied to create a uniform mode shape that can cover the changes of local structural parameters. Then the fictitious mass is removed from the mass matrix to avoid affecting the dynamic characteristics of the original structure. The mass matrix, damping matrix, stiffness matrix and aerodynamic matrix under different parameters will be generalized with this mode shape. The flutter equation in the fictitious mass modal space is established, which is solved by the g method, and the flutter velocity of the aircraft with different parameters is obtained. In this paper, a fast analysis method of aircraft flutter is established, which can effectively reduce the work load of modal analysis and improve the efficiency of aircraft scheme phase analysis when carrying out sensitivity analysis in the face of a large number of parameters. Through the comparative analysis of examples, it can be seen that the calculation accuracy of this method is basically consistent with the traditional method, which meets the engineering needs.

Key words: aeroelasticity, flutter, fictitious mass method, mode analysis, generalize