Aircraft noise is a major issue in urban areas and is one of the research topics within the FP7 SONORUS project. Current methods for determining the impact of aircraft noise on annoyance and sleep disturbance are based on energetic quantities neglecting the dynamic character of the sound. To obtain a more complete representation of annoyance, one should predict the audible aircraft sound and determine the impact of the aircraft sound on people. In a related project at Empa, sonAIR, recordings were made of aircraft taking off and landing. These recordings were made at several positions and with several microphones simultaneously. Combined with cockpit data, flight path information and an inverse sound propagation model, this gives the possibility to determine the emission as function of aircraft conditions and observer angle. An inverse sound propagation model is used to determine the emission in the time-domain. The obtained signal corresponds to the immission of a microphone flying along with the aircraft and rotating about it. The time-domain approach allows extracting narrowband information like tones and time-dependent variations like modulations.

Slides of the presentation I gave at EuroNoise 2015 in Maastricht, The Netherlands.