A piloted, fuel cell-powered aircraft was flown by Boeing three times during February and March.
The two-seat Diamond Aircraft Dimona motor-glider, with a 16.3m (53.5ft) wingspan, was modified by Boeing Research and Technology Europe (BR&TE), of Madrid, with a proton exchange membrane (PEM) fuel cell, lithium-ion battery hybrid system.
It powered an electric motor coupled to a conventional propeller.
Flown straight and level at 3,300ft (1,000m) on fuel cell power alone for a maximum of 20min at a cruising speed of 54kt (100km/h), the aircraft climbed to its test altitude using a combination of battery and fuel cell power after taking off from the Ocaña airfield, south of Madrid, operated by the Spanish company Senasa.
Despite this use of fuel cells, Boeing does not envision the technology ever providing primary power for large passenger aircraft.
Instead, it thinks PEM cells could power small manned and unmanned air vehicles. Boeing expects that, over the longer term, solid oxide fuel cells could be used for airliners' auxiliary power units.
BR&TE, part of the Boeing Phantom Works advanced research and development unit, has worked with Boeing Commercial Airplanes and other partners since 2003 to design, assemble and fly the experimental aircraft.
Its other partners include France's SAFT Germany's Gore and MT Propeller Spain's Adventia, Aerlyper, Air Liquide Spain, Indra, Ingeniería de Instrumentación y Control, Inventia, Swagelok, Técnicas Aeronauticas de Madrid, Tecnobit and Universidad Politécnica de Madrid the Madrid regional government UK fuel cell specialist Intelligent Energy and US company UQM Technologies.