Assessing the influence of ground cover, buildings and meteorological conditions on annual aircraft noise exposure: sensitivity study with the simulation tool sonAIR

The next-generation aircraft noise simulation tool sonAIR was developed for the precise prediction of single flights and for acoustic optimisation of noise abatement flight procedures. As the tool is also capable to calculate complex scenarios such as yearly air operations, it may be used for noise mapping. This study evaluates different versions of the sonAIR aircraft noise model, each employing distinct input data and calculation settings, in comparison to each version as well as to the current FLULA2 model as a representative best-practice model. The analysis focuses on annual aircraft noise scenarios at Geneva Airport for the year 2017. The calculations reveal that sonAIR’s physics-based ground effect model introduces more local variability, resulting in less smooth noise contours but expected increased accuracy, especially when incorporating detailed ground properties. On average, however, the two models yield equivalent results. Further, while accounting for buildings improves local noise estimations through incorporating shielding effects, this adds complexity and substantial computational effort, making it suitable for specific investigations but impractical for large-scale noise mapping. Finally, meteorological effects reduce noise exposure close to the airport during daytime due to acoustic shadow zones, but double computational time, further constraining large-scale applicability. Additional calculations at Geneva Airport for a different year, for two operational years at Zurich Airport and for a hypothetical, idealized airport confirm the generalizability of these findings. The current results thus suggest to use sonAIR with detailed ground properties for general noise mapping, but to consider buildings and meteorological effects in the calculations for specific cases only.