Aircraft Noise: The major sources, modellÈng capabilities, and reduction possibilities

I n October 2014, the first "Joint DLR & TU Delft Aviation Noise Workshop" was organized. This publication is the executive summary of this event. Overall, 38 invited participants f r om industry, academia, and research institutions have discussed the specific topic of this first 3 day workshop, i.e. "Aircraft Noise Reduction at the Source". The concept of the workshop was to avoid the usual presentation marathon but enable detailed discussions. The invited participants w i t h their various educational, cultural, and working backgrounds have been assigned into work groups to work on specific and predefined tasks. Four specific tasks were formulated i n order to address the problem, i.e. (1) identification of main aircraft noise sources on-board of a given reference vehicle, (2) assessment of simulation capabilities for noise prediction, (3) identification and assessment of promising noise reduction concepts for the reference vehicle, and (4) integration of these measures on-board of the reference vehicle. The major noise sources on-board of the reference vehicle as identified by the participants could have been reduced significantly i f selected measures are installed on-board. These proposed measures promise to reduce the system noise by 8 dB along a take-off and by 10 dB along an approach flight. Yet, the almost 65% reduction i n perceived noise as specified by ACARE's Flight Path 2050 could not be achieved. The most effective measure has been identified as structural shielding of engine noise emission. Overall, the workshop can be understood as the first attempt to estabhsh a new and active network for international cooperation i n the field of aircraft noise.