he HB-SIA prototype took on a new challenge by making a Brussels-Le Bourget flight in unusual weather conditions for the solar plane. After flying for 16 hours above the clouds, pilot André Borschberg received a warm welcome from those who were lucky enough to witness the majestic but silent landing.
The project’s co-founders were then welcomed by the director of the Paris Air Show and representatives from Altran and other partners, inaugurating Solar Impulse’s presence as a « Special Guest » of the Paris Air Show. Altran will of course be there all week long (June 20-26).
The flight in questions:
Why did it take the HB-SIA 16 hours to cover a distance of about 300 kilometers?
The plane had to take off at dawn to benefit from the best possible weather conditions. However, its landing was decided not only by weather constraints, but also by air traffic on the Bourget and Roissy airports which prevented any attempt before 9 PM. André Borschberg flew between the two capitals in a few hours, but he had to wait patiently above Paris before he could touch down.
How did the solar airplane manage to fly with such a cloud cover?
Until 4.30 PM, the HB-SIA flew above the clouds in order to receive and store as much energy as possible from the sun’s rays. Because the clouds wouldn’t go away, it then had to fly lower, the pilot steering the aircraft in a hole in the clouds. There, he was able to fly serenely between the upper cloud cover and the lower cloud cover which dissipated little by little.
How does the pilot feel the disturbances and turbulences the plane is subjected to in flight?
Even the slightest disturbance is felt by the pilot because the HB-SIA has the wingspan of an Airbus A340 but the weight of a car (which is very light for a plane). André Borschberg confided that "the key is to go with the flow and let yourself be carried instead of fighting against the elements. There is a subtle balance to strike, and it requires a lot of work and focus."