US Patent 8650853 Noise reduction assembly for aircraft turbojet

A noise reduction assembly located at a junction plane between an air intake structure and a fan casing of an aircraft turbojet has improved acoustic properties since the alternation of acoustic and non-acoustic zones is displaced or eliminated. In particular, the inner wall of the air intake structure includes a projecting part that extends towards the aft direction beyond the junction plane, in other words the flange of the fan casing. The projecting part may be sufficiently long so that its inner skin is continuous as far as the limit between the acoustic zone and the non-acoustic zone of the nacelle.