Gizmag has followed closely the progress of Solar Impulse from back when it was just a dream through to it latest developments, which now include it’s recent runway test. For the first time, the Solar Impulse HB-SIA has ventured out under its own steam (solar power) and taxied down the runway. Entirely powered by the sun, the aircraft has a giant wingspan of 61m and is covered in almost 12,000 solar cells.
Test pilot Markus Scherdel, scrutinized by computers and an anxious team, ventured forth successfully for the low-speed runway test. He also undertook a series of acceleration and braking maneuvers of the plane that has the wingspan of a 747, but the weight of an average family sedan.
“The runway tests are necessary and involve a certain amount of risk for the landing gear. The chances of damaging the plane are greatest during low-speed ground maneuvers. The faster the plane goes the more lift it gets from its wings, meaning that there is less load on the wheels”, explained André Borschberg, co-founder and CEO of Solar Impulse.
Taking very few chances, a foam rubber safety trolley accompanied the HB-SIA during these initial ground exercises to “catch” the aircraft and prevent any damage should the landing gear have malfunctioned, which it didn’t.
The team was happy to report that the results of the initial tests met its expectations and the decision had been taken to carry on with further tests.
The next stage will involve taking the prototype up to its 35km/h take-off speed and having it do its first few “flea hops”. The objective will be to record numerous unknown parameters as the aircraft will be operating in an unexplored flight domain.
It is hoped that, in 2010, the aircraft will be able to achieve a maximum cruising height of 28000ft (8500m) and fly continuously, day and night, for 36 hours.
Video of the runway test can be seen here.