That’s what the German Antares DLR-H2 does! The picture shows the Antares DLR-H2 “…… during its technical flight trial in June 2009 at ZweibrÃ¼cken. The fuel cell is slung under the left wing and the hydrogen tank under the right wing — with a capacity of either 2 or 4.9 kilograms. The fuel cell system used to power the Antares delivers up to 25 kilowatts of electrical power, and when flying in a straight line, the aircraft only requires about ten kilowatts of power. In this situation, the fuel cell is operating at an efficiency level of approximately 52 percent…..”. More on this amazing development here.