http://www.dw-world.de/dw/article/0,,4463354,00.html/http://www.wired.com/autopia/2009/07/fuel-cell-flight/A German motor glider has become the first piloted aircraft to take off under fuel-cell power, a feat its designers believe will help hydrogen gain acceptance within the aviation industry.

The Antares DLR-H2 developed by the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt in German, which explains why it goes by the acronym DLR) took off from Hamburg Airport on Tuesday. It is a hydrogen-powered variant of the Antares 20E electric motor glider and has a 66-foot wingspan. The plane has a range of 466 miles at 186 miles per hour, but because the test flight was weighed down by prototype hydrogen tanks it only achieved 105 mph.

Although Boeing made fuel cell flight trials last year, the aircraft took to the air with help from a battery-electric motor. DLR chief Dr. Johann-Dietrich Wörner says the technology will gain broader acceptance only when planes can take off under hydrogen power alone.

“We have improved the performance capabilities and efficiency of the fuel cell to such an extent that a piloted aircraft is now able to take off using it,” Wörner says in a statement. “This enables us to demonstrate the true potential of this technology, also and perhaps specifically for applications in the aerospace sector.”

The plane’s fuel cell hangs from the left wing while the hydrogen tank hangs from the right. The fuel cell powers an electric motor through a unique direct drive system developed by Lange Aviation and the College of Advanced Technology in Berne/Biel. DLR says the fuel cell system provides up to 25 kW of electrical power, though the aircraft requires just 10 kW to cruise. When the motor glider levels off, the fuel cell achieves an efficiency of about 52 percent, the company claims. DLR says the total efficiency of the drive system, from hydrogen tank to propeller, “is in the region of 44 percent,” which it claims is about twice that of conventional internal combustion systems.

While it might be awhile before a fuel cell flight pulls up to the gate at your local airport, project manager Dr. Josef Kallo says the technological advancement shown by the DLR-H2 will have future benefits. DLR is working with Airbus to research research fuel cells as a source of auxillary power for commercial aircraft.

“At this stage, we have only tapped into a fraction of the performance capabilities of this technology for aerospace applications,” Kallo says in a statement. “The Antares DLR-H2 will help us to make much greater use of these areas of potential.”

—————————————————————————————————————

The world’s only piloted aircraft using fuel cell propulsion technology took off from Hamburg airport on Tuesday on its first public flight, proving that hydrogen-powered transportation is not a pipe dream.

During its 10-minute maiden flight, the Antares DLR-H2 aircraft was piloted by Axel Lange, the 46-year-old head of one of the companies which adapted the motor-assisted glider to demonstrate the new technology.

The “H2″ is completely CO²-free and considerably quieter than conventional gliders, and it represents a major leap in fuel cell technology.

“The power and efficiency of fuel cell technology has been improved to such an extent that a manned airplane can now take off,” said Prof. Dr. Johann-Dietrich Woerner, chairman of the board at the German Aerospace Center, DLR.

The current propulsion model and aerodynamics of the glider allows a top speed of about 170 kilometers per hour (105 mph), but work is already well advanced to raise that to 300 kph.

In its search for new ways to reduce fuel consumption and pollution from air traffic, the German ministry of economics and technology commissioned the DLR to develop an alternative aircraft propulsion system. Bildunterschrift: Großansicht des Bildes mit der Bildunterschrift:

The DLR then teamed up with Lange Aviation, BASF Fuel Cells and the Danish company Serenergy for the project, with European airplane manufacturer, Airbus, contributing some work.

Fuel cell technology already in submarines

Fuel cells, which use hydrogen as a propellant, are not expected to be usable as a primary propulsion source for passenger aircraft in the near future, but have been operational in German 212-A-class submarines since 2005.

The DLR project is aiming to develop fuel cells under real operational conditions so that they can be used as reliable on-board power supplies in civil aviation.

Further applications may arise from the combination of fuel cell systems and other regenerative energies as a power source for high-altitude and long endurance aircraft, the DLR says.