Drones and highly automated air taxis have the potential to enrich urban air transport with new possibilities. In the HorizonUAM (Urban Air Mobility) research project, DLR sought answers to the requirements of safety, efficiency, sustainability and affordability that must be met for feasible concepts. To this end, the researchers developed concepts for air taxis, stopping points, routes and air traffic management. Central flight tests of the project took place in a model city at the DLR site in Cochstedt. In a newly constructed cabin simulator at the DLR site in Braunschweig, test participants experienced and evaluated flights by air taxi using mixed reality. In addition to other studies, the views and assessment of passers-by on virtual air taxi traffic scenarios was also recorded.