Hydrogen Use for Decarbonized Aircrafts and Associated Safety Challenges

Aviation is responsible for around 2.5% of global CO2 emissions, with most aircrafts powered by kerosene. In October 2022, the UN’s International Civil Aviation Organization (ICAO) adopted the goal of reaching low carbon emissions by 2050. Anticipating this target, Airbus unveiled its ZEROe programme, targeting a decarbonized aircraft to enter in service by 2035, using hydrogen fuel. The transition to this energy vector raises many challenges in terms of design and operation concepts for both in-flight and ground conditions. These are exposed in this article. Reconciling hydrogen physical and chemical properties, aeronautical applications specifics and safety targets is an ambitious objective. Aircraft hydrogen systems will face severe environmental conditions and drastic vehicle dynamics while having to satisfy operational cycling along with ensuring adequate level of safety. Yet designing an efficient and safe hydrogen powered aircraft is only a part of the numerous subjects to tackle. Aircraft certification and standardization remain open and evolving topics that are critical towards safe designs. Wide uncertainties are still to be addressed regarding the hydrogen ecosystem, from production to distribution and ground infrastructures: airport operations, safety and regulatory framework, availability, among others. Beyond Airbus and the aeronautical industry, global commitment is key to the success of this journey towards decarbonized aviation.