Analysis on dynamic characteristics of multi-strut aircraft under main landing gear coordinated steering

Due to their large fuselage and complex landing gear configuration, multi-strut aircraft faces significant challenges in steering control and stability during ground maneuvers. These factors directly impact flight safety and airport operational efficiency. This study focuses on the AN124 aircraft and develops a mathematical model for ground turning behavior that incorporates the steering dynamics of a multi-strut landing gear system, based on fundamental principles of dynamics. Using this model, the influence of various main gear deflection strategies on turning performance is thoroughly analyzed, with particular attention to turning radius, nose gear steering torque, and tire sideslip. Three steering configurations are examined: deflection of the front main struts alone, deflection of the rear main struts alone, and simultaneous deflection of both front and rear main struts. A comparative analysis is conducted to evaluate the impact of each configuration on key performance metrics. Results show that simultaneous deflection of the front and rear main struts offers the most significant benefits. It not only reduces the sideslip coefficient of the nose wheel but also substantially decreases the aircraft's turning radius. These findings suggest that the coordinated operation of front and rear main struts should be considered in the design of multi-strut landing gear systems to optimize turning performance. This study provides a theoretical basis for the design and optimization of landing gear systems in multi-strut aircraft. It contributes to improving turning performance, reducing maneuvering risks, and enhancing airport operational efficiency.