Alternative concept for aircraft interior noise control

Abstract

Current technology for aircraft interior noise control depends on the use of weighted barriers and absorbing layers to control noise radiation into the cabin environment. This ignores the presence of structureborne flanking paths to interior structural/decorative surfaces which contribute significantly to the total cabin noise level. An alternative approach is to employ structural damping with (or without) vibration isolation to reduce noise radiated. This concept has significant potential for reducing treatment weight, because it can make use of the weight of decorative surfaces for acoustic functions. In this paper we review the results of a flight test demonstration program for this damped trim panel concept. The treated aircraft (a 12–14 passenger business jet) exhibited equal or lower noise levels to that achieved with weighted‐layer treatments with more than a 40% reduction in the weight of acoustical materials used.