Abstract: Trajectory reconstruction and aerodynamic parameter identification are carried out on the reentry flight data of the Chang’e 5 sample return capsule. The output error method is used to identify the sensor error and the initial value of the state, and to complete the trajectory reconstruction. Wind correction is performed on the reconstructed trajectory, and the corrected angle of attack and sideslip angle are obtained. The aerodynamic parameter identification is done by using the linear regression method based on the revised trajectory. The accuracy of the trajectory reconstruction result is satisfactory when compared with the external data. The deviation between the identification result and the design value is within a reasonable range, which verifies the credibility of the ground design data.

Key words: Chang’e 5 probe, Return and reentry, Reentry trajectory reconstruction, Aerodynamic parameter identification