I had heard about Solar Impulse, the first solar plane that can not only fly during the day on solar energy, but can also store energy in the batteries so that it can fly at night too, but it was nice to have Bertrand and André (both Swiss French) come visit us and come talk about their work so far, and their plans.
I had no idea that their huge plane could fly on just 4 10HP motors. That is less than a fourth of the power than the average US car has, or my new car has 15 times more power than their entire plane! Note that it is a super efficient glider that only flies at 25-30kts (i.e. a very slow sleep and wind currents can push you much faster than it can propel itself). This is not about to take passengers across the Atlantic quite yet, but the idea is to work on milestones one piece at a time.
So far, they have flown over 24H by charging batteries during the day, climbing high, and gliding slowly down (1ft/sec) from very high altitude at night while using batteries to sustain flight when they are low enough that they should use power to maintain altitude.
Next, they're planning on flying across the US and their end goal is being able to fly around the world.
Next, we went to Moffett to see their plane (which had been brought inside a bigger plane and put back together). You have to see it in person to see how big it actually is:
Bertrand and André, interviewed by Pablo, one of our local pilots
The plane is about as wide as a 747 while the pilot cabin is smaller than the planes I fly. It was difficult get a picture from end to end in the dark hangar, but these pictures give some idea:
I got to see the materials they use, that was impressive in itself: super light but solid honeycomb, as well as foam. The spars are made out of super light carbon fiber, the same kind that goes in expensive supercars due to its strength to weight ratio:
the solar panels from sunpower are also super thin and super light
It was really cool to meet with Bertrand and André, and see their first plane. V2 is going to allow for 2 pilots, better avionics, and ability for pilots to stay airborne longer.
You can go to http://www.solarimpulse.com/#6914 to see how the plane was rebuilt at Moffett. From there, they are planning on flying across America.