[Yo-Yo]

As an RC dabbler, I'd say you're better off just putting in bigger batteries. LiPos cannot be charged while they are in use, and must be charged through the balance port. Also the weight penalty of a gasoline motor and generator would far outweigh the weight of additional LiPos.

But the concept of a motor-generator in a quad copter is intriguing, and I'm sure it's been done before, but since it isn't commercially available, there must not be enough duration or payload to make it better than a LiPo powered quad copter.

As for just a glow powered helicopter, heck, there are literally thousands to choose from on the market already.

[Mr. K]

I was wondering about using batteries similar to those found in a computer laptop? I know I have those plugged in and charging while I am using it.

Unless the load from RC motors is too great

My whole idea is to get around the limitations of the amount of time you can fly. With batteries it is minute. I want to make it so you can fly as long as you have gasoline (just like a car)

[Mr. K]

I am also thinking of some electronic switching mechanism where some batteries are charged while others are in use