Solar-Powered Plane to Fly Around the World

securitas writes "The BBC's Carolyn Fry reports on the Solar Impulse project, a plan to circumnavigate the globe in a solar-powered airplane. Adventurers Brian Jones and Dr. Bertrand Piccard, who were the first people to circumnavigate the globe in a balloon in 1999, are behind the Solar Impulse project. The project is proceeding to the design stage after a feasability study determined that the solar-powered airplane concept is a viable idea. While other solar-powered planes like the Helios prototype have relied on a secondary power source (fuel cells), this project will be powered by solar energy alone. Batteries will store energy received in daylight hours to fly all night. The first prototype is scheduled for launch in 2006."

Comments

Fly around the world in that?

[Leffe]

The plane uses a new solar electric propulsion system which converts solar energy its panels into motion via the expulsion of ions.

Solar electric propulsion is hardly new. It's been used for getting communications satellites out to their final geosynchronous orbits for a number of years now, and NASA demonstrated using solar-powered ion engines for interplanetary primary propulsion on Deep Space 1 [nasa.gov] back in '98.

What ESA is claiming is new about this mission is that they'll be combining ion propulsion with gravity assist maneuvers. AFAIK that hasn't really been done yet (although I know some guys at JPL who're working on it), and given how difficult it can be to work out low-thrust trajectories in the first place I would imagine that successfully throwing gravity assists into the mix would be a significant acheivement.