Design Support Methodologies and Tool-chain for Hydrogen Fuel Cell Regional and Urban Air Mobility Aircraft

C56-18e-273014 The rapidly expanding market for Urban Air Mobility (UAM) aircraft features a wide range of air vehicle configurations and propulsion options, including multiple paths for exploiting the potential of electric Vertical Takeoff and Landing (eVTOL) and electric Short/Conventional Takeoff and Landing (eS/CTOL) designs. A particularly promising propulsion solution for this sector uses electric motors driven by hydrogen fuel cell (H2FC) technology. Along with the environmentally positive qualities of hydrogen as a fuel, H2FC systems are also well suited for air mobility since they provide much greater energy density by mass than existing or projected battery technology. While fuel cell systems have been well developed for several niche ground and space applications, substantial technical advances are called for to optimize these systems for commercial aviation. Additional needs include: development of a clear understanding of the impact of storage weight fraction; fuel cell stack heat dissipation under airflow; and overall power to weight ratio of realistic systems. In addition, a careful definition is required of critical operational and business issues associated with vehicles powered by these systems, notably capital costs for their development, likely operating costs, component life and durability, the impact of new hydrogen infrastructure/hubs, as well as comparing the advantages of H2FC systems to conventional and alternative electric powertrain systems. This project will provide a knowledge base and a software toolchain to support the technical and economic analysis of a wide range of candidate eVTOL and eC/STOL aircraft powered by H2FC systems and sized for passenger transport. A supporting goal will be to provide an understanding of tradeoffs among alternative powertrain systems (e.g., internal combustion (IC), battery electric, and hybrid systems). This project will exploit a substantial body of prior work on the development of fuel cell models for conceptual design of hydrogen eVTOL aircraft as well as full-featured air vehicle performance models that will allow direct assessment of aircraft performance and capture critical air vehicle performance parameters (e.g., maximum takeoff weight, payload, range, and fuel consumption) for benchmark missions and for a wide range of potential configurations. Our proposed work will notably go beyond the requested focus on development of a scale model system and include the assessment of full-scale system performance in passenger- and cargo-carrying vehicles, using tools validated for vehicles already in-flight test. This approach will be made possible by collaboration of the lead organization, Continuum Dynamics, Inc. (CDI) with investigators at the University of Maryland with extensive model development and laboratory-scale background in hydrogen fuel cell systems for eVTOL and supporting consultants experienced in assessment of economic analysis of both air transport and fuel cell technology. This work will also leverage experience acquired by CDI in five years of supporting air vehicle developers at Alakai Technologies who are engaged in current testing a of passenger-capable hydrogen eVTOL aircraft. In term of long-term commercialization potential, a key outcome of the work will be a software toolchain integrating advanced design models of the air vehicle with new powertrain modeling capabilities encompassing H2FC systems as well as alternative power plants. This toolchain will be structured to support trade studies of the vehicle characteristics necessary to address important commercial missions. This will in turn enable application of the modeling by a wide range of customers in the growing electric aviation sector, including air vehicle and component manufacturers as well as prospective fleet operators. It will also enable a key goal of Phase I: a technical and economic analysis (TEA) of H2FC systems while also allowing execution of such analyses by prospective customers.