Abstract:A two-blade fixed pitch propeller from an aero-piston engine was selected as the analysis object, based on the general finite element software platform, two 3-D finite element models of the integral structure and the single blade structure of the propeller were established. According to the performance parameters of the aero-piston powerplant, the aerodynamic and centrifugal loads on the propeller under the ground take-off condition were calculated. Then, by using the finite element software, the natural frequencies and modes of the integral structure and the single blade structure of the propeller under the action of non-external load, only aerodynamic load, only centrifugal load, and both aerodynamic and centrifugal load were calculated. Through the analysis of the calculation results, the influence rules of aerodynamic load, centrifugal load, shape factor (integral structure or single blade structure) on vibration frequency and mode had been found, which have important guiding significance for the vibration characteristics calculation and analysis of other rotating parts that interact with gas.