A Realistic Rotorcraft Noise Footprint Computation for Low-Noise Trajectory Optimization

This paper introduces recent developments in the computation of rotorcraft noise footprint, implemented in an Airbus Helicopters' internal software. The paper presents the main ingredients that have led to enhance the efficiency and accuracy of such noise footprint computation. This includes taking into account both the particularities of turns in noise emission and the influence of the wind on noise propagation. Furthermore, the software is able to assess a real traffic environmental impact, since computations are done within a realistic 3D simulation environment, taking into account both the curvature of the Earth and the topography of the ground. A variety of noise annoyance indicators can be computed thanks to the coupling with demographic and background noise data. Such realistic noise footprint computation is embedded in a tailored algorithmic scheme aiming at optimizing rotorcraft trajectories in such a way that their associated noise footprint is minimized. The proposed optimization approach has been tested on multiple real-world case studies, showing significant prospective noise reduction compared to reference trajectories.