Urban Air Mobility (UAM) is a new air transportation system for passengers and cargo in urban environments, enabled by new technologies and integrated into multimodal transportation systems. The vision of UAM comprises the mass use in urban and suburban environments, complementing existing transportation systems and contributing to the decarbonization of the transport sector. Initial attempts to create a market for urban air transportation in the last century failed due to lack of profitability and community acceptance. Technological advances in numerous fields over the past few decades have led to a renewed interest in urban air transportation. UAM is expected to benefit users and to also have a positive impact on the economy by creating new markets and employment opportunities for manufacturing and operation of UAM vehicles and the construction of related ground infrastructure. However, there are also concerns about noise, safety and security, privacy and environmental impacts. Therefore, the UAM system needs to be designed carefully to become safe, affordable, accessible, environmentally friendly, economically viable and thus sustainable. This paper provides an overview of selected key research topics related to UAM and how the German Aerospace Center (DLR) contributed to this research in the project "HorizonUAM - Urban Air Mobility Research at the German Aerospace Center (DLR)". Selected research results on the topics of market potential and public acceptance, vehicle design (including battery degradation, onboard systems, cabin design, cabin simulation), infrastructure, operations (including U-space, safe autonomy, navigation, communication, cost modeling) and overall system modeling are briefly presented.

Urban air mobility is a rapidly growing field of research. While drones or unmanned aerial vehicles have been operated mainly in the private and military sector in the past, an increasing range of opportunities is opening up for commercial applications. A new multitude of passenger-carrying drone or air taxi concepts promises to fulfill the dream of flying above congested urban areas. While early research has been focusing on vehicle development, solutions for urban air traffic management are lagging behind. This paper collects and reviews the main findings of past urban-air-mobility-related research projects at the German Aerospace Center (DLR) to serve as a basis for ongoing research from an air traffic management perspective.

In security-critical situations in the maritime area, ship-based deployment of remotely piloted aircraft systems could enable automated acquisition of aerial images and other sensor data. If intervention is required, response times of federal institutions could be shortened significantly without endangering personnel. This paper gives an overview of research undertaken at DLR in cooperation with the German Federal Police for Maritime Tasks. For a safe ship deck landing of an unmanned rotorcraft a combination of precise navigation and tethered landing system has been developed and patented. Relative double-difference algorithms are used for precise navigation of the rotorcraft to a hover point over the ship deck. From there, an electromagnetic winch is lowered from the rotorcraft that connects to the ship deck. The resulting cable connection is used for aligning the rotorcraft during landing and securing it on the ship deck afterwards. First demonstrations on a real ship deck show the feasibility of the system.

For the successful development and implementation of novel concepts and technology, the acceptance of potential users is crucial. Therefore, within the project HorizonUAM of the German Aerospace Center (DLR), we investigated passengers’ acceptance of air taxis. One challenge is that not many people have real experiences with urban air mobility (UAM) at the moment and thus requirements formulated by potential users refer to rather abstract concepts. To allow participants to gain realistic impressions of UAM concepts, a mixed reality (MR) Air Taxi Simulator was set up. In a study, 30 participants experienced an inner-city business shuttle flight. We assessed the influence of another person on board on wellbeing and information needs in nominal (experiment 1) and non-nominal situations (experiment 2). For the latter, participants experienced a re-routing of the flight due to landing side unavailability. During and after the flights, participants answered questionnaires and extensive interviews were conducted. The study produced empirical data on relevant factors regarding interaction, information needs, and comfort within an air taxi. The findings show that passengers want to be informed about intentions of the vehicle. The presence of a flight attendant on board is not necessary but can increase wellbeing especially during non-nominal situations.

Urban Air Mobility (UAM) has emerged as a potential game changer for urban transportation, promising faster, more efficient and affordable services. However, beyond the visionary concepts, it is crucial to explore and discuss the opportunities and challenges of UAM and vertidrome operations also from a research perspective. The DLR research project HorizonUAM aimed at a holistic research approach in which vertidromes and vertidrome networks play a significant role. This vertidrome centered project report covers various aspects and methodological approaches addressing design and operation, UAM airspace management, network optimization and the integration of air taxi operations into airport environment. Moreover, the conceptual and temporary development of a modular 1:4 scale model city lays the foundation for future UAM flight trials. Based on three years of dedicated research within HorizonUAM, we focus here on operational challenges, proposed solutions and required frameworks to ensure safe and efficient vertidrome operations