Cranfield Aerospace Solutions (CAeS), a spinout from Cranfield University in Bedford, England, has shifted its focus to sustainable aviation by developing a pioneering hydrogen fuel cell system for aircraft. With Jenny Kavanagh leading the transformation as the Chief Strategy Officer, the company aims to tackle the decarbonisation of aviation for a greener future. CAeS, known for solving R&D challenges for aerospace giants like Airbus and Boeing, recognized the limitations of hybrid-electric systems and found hydrogen to be the most viable solution for true decarbonisation. Their hydrogen fuel cell system, described as the world's most power-dense, is adaptable to various aviation applications, with a strong emphasis on eVTOLs. The company's design approach prioritizes scalability and safety, ensuring certifiability and efficiency in energy delivery. By combining hydrogen fuel cells with batteries optimized for power in eVTOLs, CAeS aims to revolutionize the sector by reducing weight, increasing range, and lowering operating costs. While focusing on retrofitting aircraft initially, CAeS envisions hydrogen-powered eVTOLs becoming operational by the end of the decade, paving the way for broader decarbonisation of aviation. However, regulatory hurdles remain a challenge, as the company must prove the safety and reliability of hydrogen technology to meet stringent aviation standards. Jenny Kavanagh stresses the importance of engaging regulators to ensure the seamless integration of hydrogen fuel technology into the Advanced Air Mobility sector, setting the stage for sustainable aviation advancements.