Impact of LH₂ Fuel Cell-Electric Propulsion on Aircraft Configuration and Integration

This study considers the aircraft configuration impact of a liquid hydrogen/fuel cell electric propulsion system when integrated into a single-aisle, transport-class aircraft having consistent performance capability of a Boeing 737-800. This study demonstrates that, given reasonable developments in future component and subsystem technologies for a 2050 entry into service date, the design of an aircraft with a liquid hydrogen/fuel cell-based propulsion system can be feasibly achieved while still meeting mission-level performance characteristics consistent with modern commercial aircraft. While the use of hydrogen storage and fuel cell power systems does lead to an increase in maximum takeoff weight of the aircraft, relative to modern kerosene and turbofan-powered systems, the hydrogen fuel cell configuration benefits from leveraging distributed electric propulsion advantages, higher electrochemical efficiency than comparable thermal engines, and decreased thrust lapse rate with altitude when an independent inlet compression system is used. However, several challenges remain related to fuel cell system thermal management, requiring careful tradeoffs in fuel cell system composition, heat exchanger weight, and drag. Nevertheless, these results reveal the promising ability of a liquid hydrogen/fuel cell-based commercial aircraft to serve as a feasible replacement of narrow-body transport aircraft to help meet climate goals set for the aviation industry.