EASA has reviewed more than 150 VTOL project configurations, at different stages of maturity, all aiming at addressing a potentially new market. The available data shows that there are a wide variety of configurations with limited common characteristics except for a VTOL capability and distributed propulsion. Despite having design characteristics of aeroplanes, rotorcraft or both, in most cases EASA was not able to classify these new vehicles as being either a conventional aeroplane or a rotorcraft as covered by the existing certification specifications.
Applying either the certification specifications for aeroplane or for rotorcraft, depending on whether they are rather an aeroplane or rather a rotorcraft, and only adding some modifications would not ensure equal treatment. These new types of vehicles are designed to address the same new market – even though not always the same segments. However CS-23 and CS-27 have significant differences, especially in terms of system Safety Objectives and Operational aspects. EASA opinion is that it would not be fair to treat applicants differently based on the regulatory starting point (CS-23 or CS-27) as it would probably favour some configurations, thus preventing potentially innovative concepts to compete on the market.
Instead, EASA favours to use objective based certification requirements, which provide the necessary flexibility to certify innovative state-of-the-art designs and technology, to establish a common set of conditions for the certification of these new concepts. Therefore EASA developed this VTOL Special Condition extensively based on CS-23 Amendment 5, which is also largely harmonised with the FAAs Part 23, integrating elements of CS-27 and new elements where deemed appropriate. Accepted Means of Compliance (AMC) will be developed and, when considered necessary, the most significant ones may be consulted publicly.
The establishment of a common set of conditions will enable a fair competition and clarity for future potential applicants. In addition, it will enable EASA to consider all vehicles with a Certification Basis based on the VTOL Special Condition as “Special Category” aircraft. This classification will provide greater flexibility in the Operational regulatory framework by enabling to tailor requirements to this type of aircraft rather than having to use aeroplane or helicopter regulations.