The bird ingestion test is an important means of verifying the safety and reliability of aviation engines. In order to investigate the variation of flight trajectory after the ejection of bird body in engine bird ingestion tests and optimize bird ejection strategies, dynamic mesh technique was employed to calculate and analyze the trajectory of bird body using a six-degree-of-freedom model. The results indicate that after the ejection of bird body, a high-pressure region is formed at the shoulder area while a low-pressure region is formed at the tail. This generates aerodynamic drag, with the maximum drag occurring in the direction of motion. The drag force stabilizes at a certain value during the flight process. The aerodynamic forces acting on the bird body in the vertical and lateral directions are small, but exhibit large fluctuations with no regular pattern. The bird body experiences minimal speed decay during flight and follows a straight trajectory, making it feasible to launch the bird body to the desired location using direct aiming.