Aircraft Engine Exhaust Nozzle System for Jet Noise Reduction

A system of nozzles and pylons that redistributes jet exhaust noise sources upstream to reduce jet noise has been developed. Certain aircraft configurations install the propulsion engines above the wing or tail surfaces, or above the fuselage, or in some cases above the structure that is a blend of the wing and body or hybrid wing body aircraft. In these aircraft configurations, reducing noise propagation to the community below is possible by using the aircraft as an acoustic shield for the sources associated with the engine. The more difficult engine noises to be shielded are from the jet exhaust because they are typically distributed downstream, the equivalent of several engine nozzle diameters. This innovation redistributes jet exhaust upstream to reduce noise.