Abstract: In theis paper, the characteristics of sound insulation of a typical aicraft sidewall structure have been investigated. The influence of the frames and stringers on the bending rigidity of the aircraft sidewall skin has been taken into account in computation of sound transmission coefficient and the stiffness term in sound transmission loss has been revised. The sound insulation computations and experiments of two types of sindewall structures, with and without the add-on accoustic treatments respectively, have been carried out, The theoretical results agree with the measured results on the whole. Some reference principles for the sound insulation design of aircraft cabin are presented in this paper.

Key words: sound transmission loss, transmission coefficient, sound insulation