Noise Footprint Assessment at a Vertiport for Different Approach and Departure Procedures of a Tilt-Wing Air-Taxi 2023-01-1103

Community noise at vertiports is one of the most important questions related to upcoming urban air mobility (UAM) operations. While fixed-wing and/or fixed-rotor aircraft can mainly be treated by their changing operational parameters, such as rotor or propeller rpm, tilt-wing or tilt-engine configurations are more difficult to simulate because of their constantly changing noise emission and spatial radiation characteristics. The work presented in this paper is providing an overview of the noise situation at a virtual vertiport which is being approached and departed by a tilt-wing air-taxi in different ways. Two different approach and one departure procedures were simulated with the same generic air-taxi. The noise emission was described by using semi-empiric methods. During the air-taxi’s decent and climb, different tilt configurations were included, mainly defined by the time dependent engine’s tilt-angle but also related to different approach paths. Each approach or departure procedure was providing specific and individually time dependent changing noise emission characteristics which were used for noise footprint mapping around the touch-down or lift-off point. Different noise metrics were computed, including some which are representative to indicate noise annoyance among the vertiport’s neighborhood. It was expected that each procedure will generate its own specific community noise situation in the vicinity of the vertiport, and thus may provide an early recommendation for later operations. The results were compared towards each other. Additionally, a simulated certification flyover according to ICAO Chapter 13 - which is about the noise certification of tilt-rotor aircraft - was set into relation to the vertiport’s community noise.