That is awesome, but what's the point in using batteries? It's just a sop to the environment that drastically limits the device's potential. The fact is that hydrocarbon fuel is still the best, highest density energy transport we have. Batteries are still weak and, especially for flight, awfully heavy.<p>Keep the electric motors but ditch the batteries and replace it with a small gas turbine generator. For the same weight, you could probably increase the flight time by a factor of 10, well beyond the willingness of most people to sit in that thing ...