Application of Noise-Exposure Forecast Contours to Noise-Reduction Tradeoff Studies

Noise Exposure Forecast (NEF) procedures were developed to depict areas near airports having different degrees of noise exposure and differing impact upon land use. The NEF procedures represent a refinement of earlier airport land use planning procedures based upon the Composite Noise Rating (CNR). The NEF procedures have recently been applied to study the differences in total noise exposure resulting from various proposed modifications of current jet-transport aircraft-noise characteristics and changes in takeoff and landing profiles. Preliminary results are available based upon consideration of two different mixes of aircraft types operating from a hypothetical single-runway airport. Changes in noise exposure are summarized in terms of the percentage of land areas falling within NEF 30 and NEF 40 contours. [Work supported by the Federal Aviation Administration under contract.]