Westchester County recently commissioned the environmental consulting firm HMMH to produce an updated study of noise generated by arriving and departing aircraft from HPN using detailed data from 2013, 2016 and 2018. The same firm was involved in the County's previous noise study, completed in the 2000s, which looked at noise levels for 1989, 1999 and 2005. The study involved using detailed radar data showing the precise location, altitude, type and time of each aircraft arriving or departing from HPN. This data was then passed into a model to generate detailed noise contours showing the levels of noise at points surrounding the airport. Previous efforts comparing such models against actual nose levels measured with microphones around Westchester County found such models to be accurate in predicting noise levels at HPN. The first results from the new study were presented at the October meeting of the Airport Advisory Board (AAB). When combined with the previous studies, the current results show that the airport continues to show steady and significant contractions in the noise contours surrounding the airport in the period from the 80s, 90s, 00s and today. The consultant attributed these continued reductions in noise to a combination of significantly lower traffic levels in recent years at HPN relative to periods past along with the overall trend of the aviation fleet becoming quieter, particularly with the near elimination of the very loud stage 2 aircraft.
The County asked the study to also review traffic levels and flight patterns north of the airport as this the most common location of noise complaints. The consultants noted that the extended centerline of runway 16-34 do see a significant concentration of traffic relative to other parts of the County; however, in addressing the question if flight paths have changed the study did not find any significant change in overall flight paths into or out of the airport during the 2013-2018 period reviewed. Such results are consistent with earlier studies conducted by the AAB which reviewed radar data going back to 2005 and also did not observe significant changes in the overall flight paths used for arriving or departing aircraft from HPN. The study noted that while the overall trend of traffic at the airport has been downward, the volume of traffic on the 16 vs. 34 side of the airport does fluctuate year to year line with the use of 16 vs. 34 from weather and operational considerations. These results are also in line with previous research published by the AAB, which showed similar ups and downs in traffic experienced on either side of the airport. The previous AAB study went further back in time to 2005 and found that despite these yearly fluctuations the overall levels of traffic north of the airport are currently lower than decades past, broadly in line with the overall trend of lower traffic levels at HPN. The AAB previously recommended that alternative visual approach procedures may be one way to scatter traffic off the extended centerlines on days with good weather.