[m-watson]

I would guess the key here is the "researchers reported that they had developed a drone they're calling the CoulombFly, which is capable of self-powered hovering for as long as the Sun is shining."

It only seems to operate off the solar power, no additional power. So the light keeps shining, the drone keeps flying.

[abeppu]

Right, I'm can see that. I'm asking, is this the first example in the solar rotary-wing (miniature) aircraft category, or are there any other prior examples?

[nathancahill]

Also.. ground effect?