Test flights will take place this year in Spain.

           The demonstrator uses a Proton Exchange Membrane (PEM) fuel cell/lithium-ion battery hybrid system to power an electric motor, which is coupled to a conventional propeller. During takeoff and climb, when the most power is needed, the system draws on its lightweight batteries. Successful flight tests will demonstrate for the first time that a manned airplane can fly with fuel cells as the only power source.

           The demonstrator aircraft is a Dimona motor glider built by Diamond Aircraft Industries of Austria. With a wingspan of 16.3 m (53.5 ft), the plane should cruise at about 100 km/hr (62 mph) using fuel-cell power.

            "While Boeing does not envision that fuel cells will provide primary power for future commercial airplanes, demonstrations like this could pave the way for using this technology in small manned and unmanned aircraft," says Francisco Escarti, managing director Boeing Research and Technology (Europe).