Hydrogen as a fuel is considered to be an important route towards future sustainable aviation. For aviation
applications, hydrogen presents several key advantages: it allows for the elimination of carbon emissions in
flight and along the entire life cycle. Its usage in fuel cells allows eliminating NOx and particles. When burnt
in a turbine engine, very low particle emissions can be expected, as well as reduced NOx emissions, provided that the combustion system is optimised. However, water vapour emissions need to be carefully managed.
Overall, the use of hydrogen in thermal (combustion) engines is also expected to yield significant benefits in
comparison to non-CO2 emissions (high altitude phenomena) that result from conventional kerosene fuelledaircraft.