a bird deflector and air replacement system for a jet engine , the bird deflector being conical or arcuate in shape as formed by suitable longitudinal and lateral interconnected bars , and the air replacement apparatus being one of a frustum or a selectively perforated tube or a modified cowl with cooperating external spaced - apart channels or openings formed therearound for directing additional air into the mainstream of the jet engine inlet . the system may be manufactured as an aftermarket add - on , or it may be manufactured as original cowl equipment for respective jet engine models .