A Swiss effort to fly a solar-powered aircraft across the USA is expected to launch from San Franciso, California, this May.
Called Solar Impulse, the aircraft will ultimately fly to New York, New York, via five airports. Stops, which could last several days, are expected in Phoenix, Arizona, and Fort Worth, Texas, but organisers have not decided where the aircraft will land for its third stop. The fourth stop will likely be Washington, DC before the solar-powered machine flies to New York in July. If the cross country trip is successful, Solar Impulse will attempt a round-the-world journey in 2015, which will be flown using a larger version of the aircraft that is currently under construction.
Pilots Bertrand Piccard and André Borschberg will alternate flying the Solar Impulse aircraft during each leg of the journey. The aircraft can only accommodate one crewmember at a time. Borschberg says that the aircraft, which can remain in the air for 24h at a time, could make the coast to coast journey in one go, but the team chose not to do so.
According to Solar Impulse, the first prototype that will be flying across the USA has 200m² (2,150ft²) of photovoltaic cells generating 250W/m² (0.33hp/m²). The aircraft's four brush-less electric motors generate about 8hp (6kW) each propelling the aircraft at airspeeds of 37.8kt (70km/h), Piccard says. Against strong headwinds, he says, he has technically been flying backwards relative to the ground.