Noise from Emerging Technology Aircraft (ETA) - Experience from EASA

(Updated September 2022)

In the recent years, EASA has received several applications both from Urban Air Mobility (UAM) and Drone manufacturers, for which the noise requirements are not covered by Annex 16 and are addressed on an individual basis until a general noise requirement scheme applicable to these designs is available. This is usually achieved through a case-by-case assessment to establish the most appropriate requirements, which may include necessary deviations from existing Annex 16 chapters or the need for dedicated new procedures (for instance in a Hovering phase).

EASA has adopted a risk-based approach classification of UAS's according to their operational envelope. While all UAS's of the "Open" category of operations (with a weight below 25 kg, operating in visual line of sight and under 120 meters) now have applicable noise requirements2. Appropriate noise measurement schemes and limits are being developed to cover the other categories.

To that end, some extensive studies are being conducted within EASA Framework Contracts to provide a better understanding of the distinct noise features of UAS's, establish the most relevant noise measurement procedure and limits, with the most appropriate noise metric. In parallel, EASA commissioned a study on social acceptance of Urban Air Mobility in Europe3, which concluded that noise is the second main concern expressed by citizens (after safety). The psycho-acoustic survey carried out confirmed that UAM sounds are usually perceived more annoying than familiar city sounds and highlighted the pressing need to tackle UAM noise impacts via regulation.

EASA is building upon the results of these studies and is currently developing Guidelines for the measurement of UAS noise, which should be published for consultation in the last quarter of 2022. In parallel, EASA will foster its cooperation with ICAO and other authorities to best approach the noise certification of these vehicles in a harmonized way.

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² EASA Commission Delegated Regulation (EU) 2019/945 on unmanned aircraft systems (UAS) and on third-country operators of unmanned aircraft systems.

³ https://www.easa.europa.eu/sites/default/files/dfu/uam-full-report.pdf