Abstract: Composite structures are often used in the aerospace industry due to the advantages offered by a high strength to weight ratio. Sound transmission through an infinite laminated composite cylindrical shell is studied in the context of the transmission of airborne sound into the aircraft interior. The shell is immersed in an external fluid medium and contains internal fluid. Airflow in the external fluid medium moves with a constant velocity. An exact solution is obtained by simultaneously solving the first-order shear deformation theory (FSDT) of a laminated composite shell and the acoustic wave equations. Transmission losses (TL) obtained from numerical solutions are compared with those of other authors. The effects of structural properties and flight conditions on TL are studied for a range of values, especially, the Mach number, stack sequences, and the angle of warp. Additionally, omparisons of the transmission losses are made between the classical thin shell theory (CST) and FSDT for laminated composite nd isotropic cylindrical shells.

Key words: laminated composite shell, first-order, plane wave, transmission loss