Abstract: A hush kit for jet aircraft engine includes a respaced inlet guide vane to provide an increased space between the fixed guide vanes of the inlet and the rotating fan blades of the fan connected to the core engine, a mixer for mixing hot exhaust gas from the core engine with colder bypass fan air, and an acoustic barrel to reduce the noise generated by the mixed air flowing through the thrust reverser downstream of the core engine. The acoustic barrel includes an outer imperforate layer, an inner perforate layer and a multi-cellular core sandwiched therebetween. The ratio of the thickness of the multi-cellular core to the open area defined by the holes in the inner perforate skin of the acoustic barrel is designed to reduce noise of a particular frequency range generated by the aircraft engine. In combination, each of the components of the hush kit described herein reduce noise generated by the jet engine for compliance with Federal Aviation Administration noise reduction requirements.