Solar Impulse near test flight programme
The Solar Impulse HB-SIA prototype is in final preparations to begin its regular test flights at Payerne airfield, Switzerland.
The solar-powered experimental aircraft took off for its first brief flight during a high-speed taxi test at Dubendorf airfield, near Zurich, last December. However the energy during that flight was not generated by the solar cells but was stored in batteries onboard.
Test pilot Markus Scherdel will conduct the initial test flights at Payerne (first short circuit flight, first altitude flight, etc.) to verify the aircraft's controllability and flight behaviour. The programme initiators Bertrand Piccard and Andre Borschberg will then take turns at the controls to familiarise themselves with the aircraft and carry out a series of missions that should lead to the first night flights.
The objective is to fly full 24-hour cycles non-stop, with the aircraft's solar cells powering the four electric propeller engines and charging the batteries for the night-time part of the flight. The research initiative says piloting the Solar Impulse is a difficult and high-risk exercise because never before has such a large and lightweight aircraft (61m/200ft wingspan, 1,500kg/3,300lb) left the ground. The prototype's flight domain is still unknown.
