Comparison of methods for evaluating impacts of aviation noise on communities

Abstract

Community opposition to the noise concentration from precise NextGen Performance-Based Navigation (PBN) aircraft arrival and departure procedures poses a significant threat to the future of these procedures in the U.S. National Airspace System. A substantial number of complaints concerning airport noise come from locations outside the 65dB Day-Night Level (DNL) contour considered the significant noise exposure threshold in U.S. federal regulation. This indicates that this threshold does not sufficiently capture areas that experience annoyance related to more concentrated, lower level overflight noise at distances farther from the airport. This thesis assesses the effectiveness by which different noise analysis methods capture the locations of these airport noise complaints through examination of the noise exposure for three representative scenarios at Boston Logan International Airport using DNL and number of overflights above a noise threshold (Nabove) metrics. The three scenarios examined include the standard noise analysis methodology scenario (annual average day) as well as a day of heavy usage of a noise-sensitive runway (33L for departures), and a scenario representing a peak hour of departures on this runway. The results indicate that the 33L peak day scenario does a better job of capturing a substantial fraction of the complainants sensitive to the 33L departure trajectories (66%-87% at the 45dB-5OdB DNL thresholds) than the standard annual average day scenario. Results for the 33L peak day scenario indicate that the Nabove metric is also effective at capturing noise complaints at the 60dB day/50dB night noise threshold at exposure rates in the 25-50 overflight range (78%-84% complainant capture).