Way off topic but.... How cool is this!
These guys have built a solar plane that has the potential to stay up for ever with no fuel!!
The will attempt to fly it through the night in the next week or so.
Here is a little video from their YouTube channel. Cheers!
They made it first.. I've been a fan for a long time. Seems like the trick is specialty motors efficient at low power and some monster propellers. Of course it's all about weight, too. Also Li-ion batteries have better energy to weight ratio than Li-Po batteries so you can easily double your flight time just by converting to Li-ion.
It is spectacular project and will be a aviation mile stone once achieved. Wishing Good luck to the team.