I have flown on the slope till long after dark. Just a sillohette of a plane in the sky. Its great till you have to land. That gets tough. Would suck with a power plane.

You need some of those glow sticks you break and they light up. You put one on the tail and one on each wingtip. Least thats the theory.

I tried electric lights one time, but it made the glider too heavy to fly. It didn't work well.