The technology demonstrator "ZALbatros" is a hexacopter powered by a hybrid system which is to be used as a development platform for future projects. An essential component is the modular propulsion system, consisting of a combination of two fuel cell systems and lithium polymer accumulators. To supply the fuel cells with hydrogen, a pressure tank is initially provided and installed centrally on the aircraft. From this tank, the chemically bound energy is converted into electrical energy in the fuel cells and fed at the appropriate voltage to three of the six drive motors in each case. Successful demonstration of a flight time of 2 hours and 15 minutes.