Components Development and Experimental Testing for an Onboard Liquid Hydrogen Supply and Conditioning System in High-Power Fuel Cell Aviation Applications

Expected Outcome:Cryogenically stored hydrogen is the preferred energy carrier for commercial aircraft powered by fuel cells due to its better volumetric energy density. This conditioning system connects the cryogenic hydrogen storage to all onboard propulsion and auxiliary systems, that directly consume hydrogen. However, since fuel cells require gaseous hydrogen, the hydrogen supply system should reliably evaporate hydrogen and provide stable pressure and temperature outputs across a wide range of operating conditions and varying fuel demands, during different flight phases. The system should also be capable of responding to critical scenarios, such as (partial) engine failure, ensuring continuous hydrogen supply to remaining power units. Furthermore, it should be lightweight and aerodynamically efficient, to avoid degrading performance or interfering with flight dynamics.Such an LH2 supply and conditioning system shall be developed in cooperation between the Clean Aviation and Clean Hydrogen Joint Undertakings, requiring two projects to run in parallel and in synergy[1]. More specifically, while the Clean Aviation JU’s project will focus on creating a foundation for a certifiable hydrogen supply and conditioning system by defining system-level requirements, developing system architecture designs and carrying out system performance tests with a demonstrator system in the context of the Call Topic HORIZON-JU-CLEAN-AVIATION-2026-04-HPA-02: “Demonstration of an integrated hydrogen fuel system for a fully electric hydrogen fuel cell powered aircraft”, this topic focuses on development and testing of key specific components for LH2 supply and conditioning systems for Fuel Cells based electric propulsion such as those specified in the Scope of this topic text. While Clean Aviation is responsible for the development of the overall system architecture and the design and testing of architecture-driving components such as the LH₂ pump and heat exchanger, the Clean Hydrogen