EASA issues draft regulations for air taxis in cities; AviaCert provides a brief overview of future challenges in UAM

Although helicopter taxis were already operating in New York City between the Pan Am Building in Manhattan and JFK Airport in the 1950s, the idea of taxi-like shuttle services using aircraft has been given a new boost by technological progress in the 21st century. Electric Vertical Take-Off and Landing aircraft (eVTOLs) are expected to form the basis of a quiet, safe, efficient and sustainable urban air transportation system of the future. There are already more than 700 eVTOL designs currently in development by 350 companies and innovators. And those numbers are certain to keep rising. According to EASA SC-VTOL, these designs are classed as requiring "Enhanced" certification, denoting an extensive approval procedure. The safety standard for eVTOLs is deliberately set to mirror that for conventional airliners (EASA SC-25). Despite this exacting standard, passenger safety concerns - in terms of both safety and security - together with noise emissions are the most frequently cited issues in surveys regarding the implementation of UAM. However, in terms of social acceptance of this new mode of transportation, there is a positive trend due to its increasing presence in the media, numerous research projects and studies, and its presence at exhibitions and trade fairs.

Another challenge for the efficient and profitable operation of eVTOLs is the development of an infrastructure that meets demand. This includes, in particular, suitable take-off and landing areas with appropriate technical facilities and resources for turnaround, maintenance, repair and servicing, the so-called vertiports. EASA has already published an initial guideline (PTS-VPT-DSN) regarding the relevant technical specifications. This is part of a regulatory framework for vertiport design, certification, operation and oversight (RMT.0230) that is currently under development.  Although existing heliport or airfield infrastructure can still be used for first-generation air taxi operations, additional takeoff and landing facilities will be needed as UAM networks expand and become more dense, particularly in urban areas. Vertiports differ to conventional heliports because of their obstacle mitigation profiles, lower noise emission limits and mandatory charging infrastructure for eVTOLs. Extensive planning and/or feasibility studies are required for the development of a demand-oriented vertiport infrastructure. As flight operation areas, vertiports also require certification and approval by the relevant aviation authority.

Integrating aircraft into urban airspace also presents challenges, particularly for the existing air traffic management system. The proximity of UAM operations to major international airports and the resulting aircraft movements within control zones, as well as the increasing volume of drones in lower airspace, would quickly push air traffic controllers to or beyond their capacity limits. With the goal of safe, efficient and equitable integration of all users of lower airspace, UAM flights should also be served by a UAS Traffic Management (UTM) system in the future. Although air taxis may eventually operate autonomously, it is expected that they will initially be piloted and fly under visual flight rules (VFR) during the initial phases of operation. As a result, the appropriate solutions need to be identified and developed, particularly with regard to inter-aircraft communication, separation minima and resolution of potential conflicts.

Leading eVTOL manufacturers such as Joby Aviation or Volocopter are planning to launch their commercial flights as early as 2024. Until that time, the challenges mentioned above have to be overcome, a regulatory framework has to be specified and implemented, and the technological requirements have to be met. However, challenges and obstacles have always been an opportunity for change and progress in the history of aviation. 

With two decades of aviation experience and interdisciplinary teams, AviaCert GmbH has the necessary competencies to develop operational concepts (ConOps) for vertiports, to support companies in certifying and approving vertiports, and to conduct feasibility studies in the field of UAM. In addition, AviaCert offers extensive expertise in the areas of aviation law, compliance and certification, flight operational safety, and training and qualification.