
Video/Photo: Solar Impulse
"With the four electric motors running on sunlight, these first tests were slow, only getting up to about 10 knots. Initially the team used safety gear to protect the aircraft in case of a failure of the landing gear. But eventually the aircraft was able to taxi without the use of safety gear, just as it would for a normal take off.
Next up according to the team is taxi tests up to takeoff speed of about 20 knots for some short ‘flea hops’ into the air. First flights beyond the airport runway are expected early next year."