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DLR Plane

In civil aviation, hydrogen-powered fuel cells are regarded as potential energy providers for aircraft as they have been in space travel for some time now. Thus, fuel cell modules can supply electricity to the aircraft electrical system as emergency generator sets or as an auxiliary power unit.

Since fuel cells produce electricity more efficiently than aircraft engines, in ground operations aviation fuel can be saved and emissions reduced. Furthermore, multifunctional fuel cells can contribute to the supply of water, air humidification and the inerting of fuels.

More recently, electric aviation has been boosted by a number of small demonstration aircraft the size of unmanned drones, motor gliders or small sports aircraft with a mass of up to 1.5 t (DLR 2015). These miniature and small propeller aircraft were fitted with PEM fuel cells and lithium batteries for the drive. The custom-built electric planes were able to demonstrate the basic feasibility of hydrogen-powered fuel cells in flight operations over short distances.

About the HY4

The HY4 has a motor output of 80 kilowatts, a maximum speed of approximately 200 kilometres per hour and a cruising speed of 145 kilometres per hour. Depending on speed, altitude and load, it can achieve a range of between 750 and 1500 kilometres. The most striking feature of the HY4 is its twin fuselages, each with space for two passengers. The maximum weight of the aircraft is 1500 kilograms. "With the HY4, we now have an optimal platform to continue developing the use of fuel cells on aircraft," says Josef Kallo, responsible for the HY4 project at DLR and a Professor at the University of Ulm. "Small passenger aircraft, such as the HY4, could soon be used in regional transport as electric air taxis and offer a flexible and rapid alternative to existing means of transport."

University of Delft: Analysis of the technical feasibility of sustainable liquid hydrogen powered commercial aircraft in 2040 download