UK regulator calls for more drone and eVTOL noise data to inform rules

The UK Civil Aviation Authority has concluded that more testing of drones and eVTOL aircraft is needed to produce the noise data that will underpin future regulation, according to a report from the regulator.

The CAA's evidence base on the noise these aircraft make remains limited, drawing mainly on modelling, work in laboratories and small-scale trials, rather than sustained, large operations.

The report, Managing Noise from Emerging Aviation Technology, argues that trials and early deployments should be designed to gather both operational and noise data that can be used for rule-making. That information would feed into national noise policy for drones being developed by the Department for Transport.

Drones and eVTOL aircraft are expected to be quieter than the helicopters they may replace. The CAA warns they could still produce different patterns of noise exposure, because they fly lower, nearer to homes and include hover and vertical flight phases.

Acoustic traits matter too. The high-pitched whine of multicopter drones can make them more irritating than other sound sources at the same level, the report said.

Standard noise metrics may not capture intermittent or repeated operations well, the CAA added, and could need to be paired with event-based or sound-quality measures where that clearly improves the assessment.

The report also notes there are no internationally agreed noise-certification standards covering the full range of drones.