Solar powered plane makes first night flight
A solar powered plane has made its first night flight in an attempt to prove the technology could be commercially viable.
The Solar Impulse HB-SIA has four electric motors powered by 12,000 solar cells built into wing span as wide as a Boeing 747's.
Soon after take off the plane reached an altitude of 8,500 metres, and about two hours before sunset on Tuesday (July 6) started a slow descent.
Eventually reaching an altitude of around 1,500 metres where it carried on flying, using the energy stored in its batteries, until the next sunrise and landing in the early hours of Wednesday.
The plane landed at the Payerne airbase in Switzerland with André Borscherg, chief executive and co-founder of the Solar Impulse project, at the controls.
He said: "For seven years now, the whole team has been passionately working to achieve this first decisive step of the project."