Hamburg's mayor Ole von Beust poses next to the 'Antares DLR-H2' motor glider at the airport in Hamburg July 7, 2009. The motor glider is the first manned aircraft to be powered exclusively with a hydrogen fuel system. The fuel cell system is hidden in under-wing pods where the electricity for the on-board electronics and electric motor is generated. REUTERS/Christian Charisius (GERMANY SCI TECH TRANSPORT)