Mechanisms of Transmission and Control of Low-Frequency Sound in Aircraft Interiors

The development of a successful means of control of low frequency sound in aircraft interiors has been hindered by a lack of knowledge of the major mechanisms inherent in the problem. This paper utilizes a simplified analytical model to study the principle mechanisms behind the propeller source radiation, the fuselage response and the coupled interior acoustic field. Both passive and active means of noise control are then studied and various conclusions of their effectiveness are discussed in light of the transmission mechanisms.