Abstract: A sound suppressor exhaust structure for a jet engine. The exhaust structure has a nozzle body having a generally cylindrical forward intake opening to accommodate an aft end of a jet engine, and a generally quadrilateral aft exit opening. An openable sound suppression chamber is situated aft of the exit opening and is formed by two opposing enclosure structures each having a major surface and each hingedly attached in a clamshell manner to the nozzle body. The opposing enclosure structures are movable between an open and a closed configuration such that, when the enclosure structures are closed, a chamber having a generally quadrilateral cross section is defined and situated aft of the exit opening. Each enclosure structure has a major surface through which are substantially uniformly disposed a plurality of small apertures such that from about 15% to about 25% per square foot of each major surface is void and from about 45 to about 65 apertures are provided per square foot.