Abstract:All kinds of components are expressed in the form of static rigid body on the airplane design drawings. The wheel axle of landing gear is usually designed to be level with the ground. The drawings are also the bases of the ground loads calculation and structure strength analysis. However, in real ground handling physical scene, the body structure and landing gear will be deformed after being loaded, and the axle axis will have a deflection angle with the ground, or it will also have a deflection angle due to manufacturing deviation and assembly deviation. The influence of these deflection angles caused by structural flexibility or manufacturing deviation on the accuracy of wheel axle structure strength analysis process is of great significance in the development trend of aircraft design accuracy today. Based on finite element method, this paper analyzes the influence of main landing gear axle angle on hub structure strength by a civil aircraft under the typical ground load cases, researches the change of hub structure with different angel but in same loads case, and judges whether the axle deflection angle should be considered in the calculation and analysis, so as to provide a reference for the subsequent structural strength design of civil aircraft.