Change of community noise and noise impact with changes in air-taxi fleet compostitions over a longer period of time

Abstract

Generic air vehicles are helping to understand effects specifically related to urban air mobility (UAM) noise. Air corridors were already studied, managing complex air-taxi traffic to reduce population's exposure to higher or critical noise levels in the vicinity of a highly frequented flight paths. The results still depend on fleet compositions, which may change over shorter or longer periods because future UAM carriers can select from a variety of different air-taxi types, in some cases strongly differing in their noise characteristics. Once an air-taxi-fleet is operated at a certain vertiport, its composition may not remain the same after one month or even after one year. This study is evaluating a long-term effect with changing fleets operated on the same flight paths in the same air corridor. Besides usual noise metrics like DNL, the results provide also a first insight how metrics like the dose-response may be affected over a longer period of time. 25 acoustically diverse air-taxis were distributed inside an 8 km wide air corridor, carrying 165 single flight tracks at 5 flight levels. Approximately 60,200 movements were simulated representing short-term effects, ten times more for mid-term scenarios, and finally a large number of 1,505,000 for the long-term study.