As aviation technology continues to evolve, the function and safety of a large maneuvering have been required highly. As a large maneuvering system is becoming more and more complex, the trajectory design and simulation of a large maneuvering have become an important mean to ensure the mobile flight safety and design. The main focus of this research is to analyze the accuracy of the strap down navigation algorithm and its impact in large motorized sport state by the large maneuvering trajectory design and its inertial system simulation. The authors build the model of the maneuvering trajectory by the Mat lab program which is based on the design principle of the maneuvering flight path. Then, by using some coordinate system and the classical strap down algorithm, specially attitude updating algorithm, the location update algorithm and the velocity update algorithm, the designed maneuvering trajectory model has been simulated and the simulation results are analyzed.