Liquid Hydrogen – Status and Trends as potential Aviation Fuel

Hydrogen is constantly gaining attention as future energy carrier and is already considered as game changer for many applications. Since hydrogen-based mobility applications such as cars, buses, trucks, and trains have already entered the market as industrial available products, now also the maritime and aviation industries are progressing toward market introduction. The idea of liquid hydrogen as propellant for commercial aviation is not new but dates back to the 1970s when NASA in collaboration with Boeing and Lockheed conducted a very detailed study both concerning the aircraft itself as well as the necessary airport infrastructure. A historical overview of this development is given and likewise an overview of the development of the industrial liquid hydrogen technology. Furthermore, the principle of hydrogen liquefaction technology is presented, and the reason why liquid hydrogen can be considered as preferred aviation fuel is explained. Also, future trends for the further development of the liquid hydrogen technology are discussed. Long-term phase-out of kerosene with parallel phase-in of hydrogen in aviation has to be considered as a huge economical challenge. This chapter also refers to the necessary airport requirements when the hydrogen consumption at the airport has already reached a certain industrial-scale quantity and hydrogen aircraft are in regular fleet operation.”