Measurement and analysis of external acoustic radiation characteristics of C919 aircraft

The external radiated noise level of civil aircraft is one of the key indicators of airworthiness certification. Acquiring the external acoustic radiation characteristics of civil aircraft is a prerequisite for optimizing the external radiated noise. In this paper, a large linear microphone array was deployed on the ground and the C919 aircraft flew over along the normal direction of the array in different flight states. This paper performed the test and data analysis methods for external acoustic radiation characteristics of civil aircraft. Based on the measured data, the ground sound field distribution and sound radiation sphere were calculated and analyzed. The proposed method provides a technology for the test and analysis of radiated noise of civil aircraft. The obtained characteristics provide a basis for noise reduction of C919 aircraft.