U.S. Department of Energy - Energy Efficiency and Renewable Energy
Flight Pioneer Unveils Design for a Solar-Powered Aircraft
November 7, 2007
Bertrand Piccard, who piloted the first balloon to circle the world
non-stop, unveiled on November 5th the prototype design for the Solar
Impulse, an aircraft meant to repeat that feat using only solar power.
Called the HB-SIA, the prototype aircraft consists of a wing with a span of 200 feet, covered
with solar cells. Despite that huge wing span,
the craft will employ lightweight materials to tip the scales at only
3,300 pounds. That combination will allow the plane to fly at just
28 miles per hour, a speed that will keep energy consumption low,
allowing the solar panels to not only power the craft during the day,
but to also store up enough energy to keep it flying at night.
Construction of the HB-SIA began in June and is expected to be
complete by the summer of 2008.
However, the HB-SIA is not expected to circle the globe. Instead, it
will serve as a prototype to test both the flying characteristics and
the energy performance of the design. The craft will feature minimal
instrumentation and a non-pressurized cockpit, which will force it to stay
below 28,000 feet in elevation. Test flights are expected to begin in
the fall of 2008, and the first all-night flight should occur in 2009.
The Solar Impulse team hopes to build the final aircraft and fly it
across the Atlantic Ocean by 2011, followed sometime later by the
circumnavigation attempt. Piccard initiated the Solar Impulse project
in 2003, but since then the team has grown to a multi-disciplinary
team of 50 specialists from six countries, assisted by about 100
outside advisers. See the Solar Impulse Web site.
Previous attempts at continuous solar-powered flight have only been
performed using unmanned aircraft, and have met with mixed success. A
craft using a fuel cell for night flight crashed in 2003, but an airplane
using battery storage flew for two days straight in 2005. Earlier this
year, an unmanned solar-powered airplane set a record by flying for
54 consecutive hours with the help of battery storage. In contrast, the first manned aircraft to circle the Earth without stopping or refueling was piloted by Burt Rutan and Jeana Yeager in 1986 and flew for 216 hours, consuming 6,900 pounds of fuel.
The only solo aircraft to circle the Earth without stopping or refueling was piloted by
Steve Fossett in 2005 and flew for 67 hours, consuming more than
18,000 pounds of fuel. Fossett disappeared two months ago while flying
over Nevada and is presumed dead. See the articles on the 2003 crash,
the 2005 solar flight,
this year's solar flight, and Fossett's record flight from past issues of the EERE Network News, as well as the description of the Rutan and Yeager flight on the "Centennial of Flight" Web site, and for the latest
on Fossett, see the Steve Fossett Web site.