This paper examined the critical loading condition of a light sport aircrafts main landing gear during the impact loading condition. The new category airplane was established by the FAA in 2004. The light sport aircraft has great market demand for personnel entertainment purpose and regional transportation. The main object of this research was to establish a static and dynamic loading simulation model for the aluminum alloy landing gear of a light sport aircraft. This work also examined the critical loading parameters of the main landing gear, including the maximum take-off weight and maximum stall speed. The analysis was performed using ANSYS and LS-DYNA to establish the finite element model after simplifying the geometric characteristics and verifying the results by energy conservation, hourglass energy, and sliding energy. The study tested aluminum plates with a thickness from 15~25 mm. The results showed all the samples could sustain the required loading condition, except for the thickness of 15mm that failed under impact loading. The simulation model provides a cost-saving process compared to a real crashworthiness drop test to test the main landing gears compliance with regulations.