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.

View Video Presentation: https://doi.org/10.2514/6.2021-3200.vid Urban Air Mobility (UAM) is increasingly becoming popular for Passenger or Cargo movement in dense smart cities. Several researches so far are focused on individual vehicle architectures such as multirotor or tiltrotor etc., but not much effort in a System of systems point of view where a homogenous fleet of vehicle with different passenger capacity, speed, and propulsive energy concepts are assessed in a framework for a successful UAM operations in a given city. An effort is made in this paper wherein, vehicle architecture is derived from the Concept of Operations (CONOPS) of scenarios such as urban and suburban operations and as well as propulsion subsystem for sustainable UAM. This paper approaches UAM aircraft design driven by System of Systems (SoS) approach and an agent-based simulation supports the vehicle architecture evaluation and fleet definition. The outcome of this study are: multiple aircraft design with subsystem architectures, ideal fleet size for the respective operational scenarios, autonomy and battery technology effectiveness on UAM throughput (to efficiently provide UAM on-demand service maximum passengers within 15 min wait time), and importantly, sustainability metrics such as total fleet energy required. Several System of Systems, system and subsystem level sensitivity research questions are addressed to understand the interlevel coupling.

The implementation of urban air mobility represents a complex challenge in aviation due to the high degree of innovation required across various domains to realize it. From the use of advanced aircraft powered by novel technologies, the management of the airspace to enable high density operations, to the operation of vertiports serving as a start and end point of the flights, urban air mobility paradigm necessitates significant innovation in many aspects of civil aviation as we know it today. To understand and assess the many facets of this new paradigm, a collaborative simulation is developed to holistically evaluate the system of systems through the modeling of the stakeholders and their interactions as per the envisioned concept of operations. To this end, models of vertiport air-side operations, unmanned/manned airspace management, demand estimation and passenger mode choice, vehicle operator cost and revenues, vehicle design, and fleet management are brought together into a system of systems simulation of urban air mobility. Through collaboration, higher fidelity models of each domain can be integrated into a single environment achieving fidelity levels not easily achievable otherwise. Furthermore, the integration enables the capture of cross-domain effects and allows domain-specific studies to be evaluated at a holistic level. This work demonstrates the collaborative simulation and the process of building it through the integration of several geographically distributed tools into an agent-based simulation without the need for sharing code.

Urban Air Mobility (UAM) is an evolving concept of passenger transportation providing on-demand flights within metropolitan environments, wherefore typically fully electric vertical take-off and landing aircraft are designed. Due to the underlying battery energy constraints, the design of UAM aircraft is very sensitive. Apart from the design considerations, the impact of aircraft operations on the entire UAM transport network must be examined. As there is no data from real-world operations available, this research article utilizes a system of systems simulation framework combining aircraft design with an agent-based simulation. The underlying approach offers the possibility of studying several parameters concerning UAM aircraft design and operations. In a case study focused on intra-city transport, aircraft design aspects regarding the payload capacity, the mission profile, and the reserve requirement are studied for a multirotor configuration. Furthermore, the aircraft operations aspects are focused on the turnaround procedures, the passenger demand, and the cruise speed. The multi-level sensitivity analysis ranging from the subsystem over the system of interest to the system of systems level allows us to trace the most sensitive aspects. Especially, the sensitivity analysis of battery fast-charging and swapping shows the importance of the holistic system of systems investigations for the successful development of UAM aircraft and services.

Throughout history, wildfires have been prominent natural disasters that cause pollution, environmental damage and loss of lives. Local firefighting agencies and disaster response initiatives have typically managed to contain fires and limit damage to controllable levels. However, in recent times, due to climate change and human population growth, wildfire occurrences are becoming less predictable and result in greater cost and damage. Solutions employing new technologies and a more operations-oriented analysis, through system-of-systems (SoS), could be a promising way to combat further wildfire devastation. Designing new aircraft and strategies that can be used in human transport and firefighting is one of the goals of the COLOSSUS project. To enable international innovation, especially amongst young researchers, a student competition called the X-Challenge was released. This paper will deal with the overview of the challenge, breaking down its objectives, constraints, research contributions and outcomes. Following this paper, four different student teams will present their solutions, including innovative aircraft designs and SoS analysis methods. The knowledge gained, and successes and failures from the challenge, alongside outlook and recommendations for future challenges and SoS exploration, will be discussed in this paper.