EASA has published what it says are the world’s first proposed noise certification standards for eVTOL aircraft. The proposals, known as the Environmental Protection Technical Specifications (EPTS), are applicable to eVTOL vehicles powered by multiple vertical, non-tilting, evenly distributed rotors.
According to the European aviation regulator, the proposed specifications are intended to fill a regulatory gap and use the internationally harmonized noise certification standards for heavy helicopters as a starting point while it “collects more noise data from specific eVTOL designs through certification projects.” In addition, a hover noise level has been developed to aid in the assessment of flight operations in the vicinity of vertiports.
The proposed noise-measuring procedures and analyses are adapted to the characteristics of eVTOLs where necessary. For example, as electric vehicles are expected to be quieter than today’s conventional VTOL aircraft in certain phases of flight, there is a need to allow them to fly closer to the microphone in those phases to maintain an accurate signal-to-noise reading.
Because eVTOL vehicles do not emit nitric oxides, carbon monoxide, unburned hydrocarbons, visible smoke, or non-volatile particulate matter, no specifications for engine emissions are proposed within these EPTS. Similarly, EASA does not propose any carbon dioxide emissions or efficiency specifications for these designs at this stage. Comments on the proposals are due by June 15.