Boeing claims to have made aviation history by being the first company to fly a manned aircraft powered by hydrogen fuel cells.
The milestone was the result of a pan-European effort led by engineers from Boeing Research & Technology Europe (BR&TE) in Madrid.
Further assistance was provided from industry partners in Austria, France, Germany, Spain, and the UK.
A two-seat Dimona motor-glider with a 16.3m wingspan was used as the airframe.
It was built by Austria's Diamond Aircraft Industries and modified by BR&TE to include a proton exchange membrane (PEM) fuel cell/lithium-ion battery hybrid system to power an electric motor coupled to a conventional propeller.
Three test flights took place in February and March at the airfield in Ocaña, south of Madrid. During the flights the pilot climbed to an altitude of 1,000m above sea level using battery power and power generated by hydrogen fuel cells.
After reaching the cruise altitude and disconnecting the batteries, the pilot flew at a cruising speed of 100kph for about 20 minutes on fuel cell power.
Hydrogen fuel: Boeing claims to have made aviation history
According to Boeing researchers, PEM fuel cell technology potentially could power small manned and unmanned air vehicles. Solid oxide fuel cells could eventually be applied to secondary power-generating systems, such as auxiliary power units for large commercial airplanes.
'We are proud of our pioneering work during the past five years on the fuel cell demonstrator airplane project,' said Francisco Escarti, BR&TE's managing director. 'It is a tangible example of how we are exploring future leaps in environmental performance.'