Monday morning, September 26, many of us had our first view of an electric airplane in flight. After the weighing team rolled Jim Lee and Jeff Shingleton’s Phoenix motorglider from the hangar onto its impound location and completed initial weigh-ins for the remaining three aircraft, the airplanes were staged for the first flying event of the Green Flight Challenge sponsored by Google. With technical inspections and weighing completed, the four airplanes lined up to check their noise levels and their ability to clear an imaginary 50-foot barrier atop a cherry picker 2,000 feet from the top of the number “9” on runway 19 at Santa Rosa, California’s Charles M. Schulz Sonoma County Airport. As each aircraft rolled out to their takeoff point, the cluster of photographers under the cherry picker focused and waited for a green flag to fall at the takeoff point. All the aircraft passed cleared the 50-foot flag, and e-Genius was judged to be quietest of the entrants …
Green Flight Challenge – Day One
Sunday, September 25 marked the kickoff of the Green Flight Challenge sponsored by Google, a NASA Centennial Challenge managed by the CAFE Foundation, with a thorough technical inspection for each entrant, followed by a weigh-in. Held at the Charles M. Schulz Sonoma County Airport, the event is an event of international importance, despite the small turnout. With only four entrants making an appearance out of the original 13 that had announced and made it through the rigorous design review, there might be cause for disappointment. Consider, though, the Berblinger competition held in April at the Aero Expo in Friedrichshafen, Germany. 36 teams signed up, 24 made it to the Expo, 13 started the course and eight finished. The GFC has a comparable start-finish ratio, with many of the same issues stalling non-starters here as in Germany: lack of funds and schedule, regulation and fabrication difficulties. Despite the dropouts, Pipistrel, Stuttgart University, Phoenix Aircraft, and Embry Riddle Aeronautical University (ERAU) managed to field teams. In a …
The G4 Gets Off the Grass
Pipistrel had a good week at Oshkosh. Shortly after its G4 placed ninth in the Dead Grass Awards, an indication of the number of spectators who tramped around the perimeter of the displayed aircraft, the company could announce the first test flight of the four-seat electric motorglider. “We are pleased to announce that after long and demanding work nearly of a nearly 30-member team of developers and constructors from Pipistrel’s R & D Institute the first 4-seat electric aircraft in the world took off this morning [August 12, 2011] at 7 AM local time.” Pipistrel overcame several difficulties in achieving this milestone. Developing the electric power system, the most powerful currently in an aircraft, and importing the 450 pounds of lithium-polymer batteries needed to energize it presented many issues. Perhaps the utterly new and unique design and the possibility of that many batteries self-igniting caused insurance companies to be more than normally cautious, although one did finally step forward. Because …
Pipistrel’s Four-seat, Side-by-side Electric Airplane
One of the most anticipated presentations at this year’s Electric Aircraft Symposium in Santa Rosa, California, April 29th and 30th, was that of the CAFE Foundation’s Vice-President, Larry Ford. He had the enviable task of unveiling the contenders in the Green Flight Challenge – a mix of conventional aircraft powered by unconventional means, unconventional craft being sent aloft by a variety of the mundane and the exotic, and wildly unconventional concatenations of technologies. Pipistrel’s G4 turned out to be simple math: G2 plus G2 equals G4. The configuration could hardly be preconceived, though. According to Pipistrel USA’s Michael Coates, “This unique design has come about by grafting two Pipistrel Taurus aircraft together with a center section which is some 5 meters (16 feet) wide and includes a center pylon housing the electric engine and batteries designed to successfully carry this aircraft to the skies and hopefully to the completion of the 2011 CAFE/NASA challenge, the design bears some similarity to the twin …