Urban Air Mobility: Preliminary Noise Analysis of Commuter Operations

This study aims to estimate potential noise levels generated due to Urban Air Mobility (UAM) commuter operations in the Northern California and the Dallas-Fort Worth regions. UAM is a concept aerial transportation mode designed to bypass ground congestion using an electric vehicle with Vertical Take-Off and Landing (VTOL) capabilities. UAM vehicles are expected to be significantly quieter than traditional helicopters, but operate on a much larger scale. Commuter travel demand will not be uniformly distributed with operations concentrated in a small geographical area such as Central Business Districts (CBD) and short time windows such as morning or evening peak periods. The objective of this study is to evaluate the aircraft noise annoyance generated by commuter UAM operations using flight trajectories developed in a previous study estimating UAM commuter demand. This study estimates the noise level from overflying UAM vehicles in a full day of operation (24 hours) and identifies areas where the noise levels may pose a challenge to future UAM operations. Noise estimation is performed at the Census Block group level using the Day-Night Level (DNL) metric. We run a parametric analysis considering two scenarios in each region: the UAM vehicle has a 10 dBA and 15 dBA noise reduction compared to the Robinson R-44 helicopter. The findings indicate a considerable difference between the 10 dBA and 15 dBA reduction scenarios. Although challenging, achieving a 15-dBA reduction compared to a 10-dBA reduction could reduce land area with DNL value above 50 dBA by 94% and highly-annoyed population by 91% in Northern California. Similarly, in Dallas-Fort Worth, achieving a 15-dBA reduction compared to a 10-dBA reduction could reduce the land area with DNL value above 50 dBA by 80% and a highly annoyed population by 85%. Lastly, we analyze the high-demand vertiport in the San Francisco Financial District in the Aviation Environmental Design Tool (AEDT) to observe the DNL contours for the varying noise performance scenarios.