Easily Retrofitted, Active Noise Cancellation System

Aircraft noise abatement, particularly in the near vicinity of airports, is a serious and expensive problem for both military and civilian air fleets. Previous noise abatement efforts such as engine replacement, structural modifications, or the addition of a Hushkit, have yielded mixed results. These methods are not particularly effective at reducing noise and most also adversely impact the performance capabilities of the aircraft. With the costs of noise abatement climbing, it is imperative that a cost-effective solution to the jet noise problem be developed. Optimally, the solution would be effective for development aircraft and could be incorporated into the current fleet. Foster-Miller’s innovative Active Noise Cancellation System (ANCS) is a novel and cost-effective solution to this challenging problem. Our ANCS controls inlet engine noise over a broad band of frequencies in a narrow and adaptable geometric range of the omni-directional source. The narrow geometric location of the ANCS device is cost-effective and directly affects the particular noise source, which directionally impacts civilian areas around the airfield on takeoff. In Phase I, we performed experiments and analyses validating the principles supporting our concept. Herein, we propose the development and testing of a scaled, full-functional ANCS for inlet aircraft engine noise. (P-040436)