The Solar Impulse, a prototype aircraft powered by lithium polymer batteries recharged via solar cells, made it's first extended duration test flight this week. The aircraft, which has an impressive 200 foot wingspan, stayed aloft for 87 minutes at an altitude of up to 1,200 meters. The Solar Impulse is driven by four electric motors, each rated at ten horsepower.
If the extended testing of the Solar Impulse is successful, a second aircraft is planned for an attempted circumnavigation of the globe at the equator. The second version of the Solar Impulse will be larger still, and will feature a pressurized cockpit to allow a higher ceiling and cruising altitude.