Abstract: An acoustic absorber is made of a pot-shaped lower part with a pot bottom and side wall as well as an upper part having a horn. The horn projects into the bottom part and tapers in the direction of the pot bottom. Undesired noise is effectively reduced by the absorber. A relatively broadband, and at a given size, a relatively low-frequency absorption effect is achieved that is capable of protecting human hearing from injury or reducing the impact of noise such as on technical equipment and components.

Abstract: By means of this acoustic protection it is possible to protect the payloads of expandable launch vehicles effectively against noise emissions from the rocket propulsion system which result in damage of the payloads. For this purpose acoustic absorbers (8) tuned to a defined frequency range are provided and are arranged in foamed plastic mats (7) disposed on the insides (6) of the payload fairing (1). The acoustic absorbers (8) are composed of a cup-shaped lower part (12) and an upper part (13) having a horn (18). The horn (8) tapers in a curved-conical manner from a larger diameter (D.sub.m) to a smaller diameter (D.sub.t) and projects into the lower part (12) by a defined distance (a) from a bottom (14) thereof. Slits (21) for the dissipation of the directed flow energy occurring in the horn (18) are disposed in the wall of the horn in the area of the smaller diameter (D.sub.t).