Hydrogen’s use as a clean, lightweight fuel is held back by technological limitations and the high cost of storage and fuel cells. This project aims to overcome barriers to market entry by proving a profitable early market application in small unmanned aircraft systems (UAS) designed for marine research, extending range and payload compared with lithium batteries. A consortium comprising Cella Energy’s hydrogen materials developers, Arcola Energy’s fuel cell expertise and the Scottish Association of Marine Science’s UAS research team are working to demonstrate a flyable aircraft with innovative solid-state hydrogen storage integrated with lightweight fuel cells as a proof-of-concept for <7 kg marine UAS. Small UAS are rapidly developing tools for agriculture and public safety on land; and marine and climate research, and energy monitoring offshore, where they benefit from less restrictive aviation regulation. Civilian UAS are due to emerge as an early-adopter of highly energy dense, green power solutions like hydrogen, in advance of a revolutionary low-carbon fuel for road vehicles. This project emphasises the benefits to society of the safe use of UAS, and of hydrogen.