I'm not sure if this helps, but...........the old Cox Bearcat that I have has electrical lines as the main lines, and in the handle there is a button on the top that completes the circuit and turns the engine on...........finally, the batteries are actually hooked up to the handle, so it saves weight in the airplane. The only drawback about this design is that there really is no throttle unless you fan the button..........but I'm sure somebody could come up with an original way to put one in the handle?