Hello;Always wondered why we don't see more minicopters getting people around. I understand the danger, but it seems like with the right engineering and safety put in place it could be made to work. For safety, when a single-engined aircraft's engine fails, they're supposed to be able to land safely with no power. With a plane, this is fairly obviously as a glider. With a helicopter, the blades are disengaged, and as it falls, it goes forward and the air rushing past makes the rotors start to freely spin, generating enough lift that you have a little control, and don't just drop out of the sky like a metal stone. 2:02 is an autogyro, different to a helicopter, but illustrates the theory I mention. It only has forward propulsion, through it's propellor. This is enough, that it's heli-blades start rotating freely, and in flight they'll rotate rapidly enough to generate lift, even though it's all free movement, the engine isn't attached to them at all. The idea of a free-spinning helicopter sounds ridiculous, but really it's just like a plane operating as a glider. Just that, instead of fixed wings converting forward motion into lift, it has moving, spinning wings instead. That's what a helicopter is, rotary wings are driven to generate lift directly, rather than pushing the whole craft forward with a propellor like a plane does. Instead of the air being pushed over wings from the plane's motion, the wings are driven directly, spun, into the air at high speed, and there's your lift. Then to generate motion, you alter the pitch of the blades cyclically in such a way that there's a directional thrust. How collective pitch and stuff works in helicopters is brain-twisting, and I'm sure there are qualified heli pilots who don't understand it, so don't ask me any more than that. Anyway, point is, it's backwards. In a heli, you move the wings to generate lift, that also pushes the craft forward. In a plane, you move the plane, with a prop, and as an effect, air moves over the wings and lift comes as a side-effect. The engine power in a heli is all about going up, in a plane it's about going forward. Though I realise there are fast helicopters, not saying it's a bad choice. Their strength though is their versatility, not needing a runway. Anyway. The guy at the beginning, buzzing round in Gen H-4. That vehicle avoids needing a tail rotor, because it has 2 main rotors instead, one spins clockwise, the other anti-clockwise. So there's none of the twisting force, than a normal chopper needs a tail for. Problem there is, are they really going to free-wheel if the engine fails? Straight away, effectively enough, if even at all? Cos otherwise you're betting your entire life on that little engine. Maybe it's got an explosive parachute, the type that can launch itself even at low altitude. "Low" for flight, but still quite high enough to smash the life out of you when you hit the ground from it! So does it have that safety factor? I'm under the impression all aircraft must have a way to survive engine failure. Even experimental ones. It's going to be little use if you can only ever fly it up to 10ft, however high you think your legs can survive a drop from. Attached to a helicopter or otherwise! I hope it is OK though because it's probably the most practical one from the POV of personal air transport. Cheap and simple. A sky motorbike. Maybe future flying cars, that's how we'll know it's the future btw, will be more like ordinary planes, with a comfortable interior like a car. But things like this will just get the job done. Engine and a prop, the bare minimum. Well, 2 props. Stick a seat on somewhere so you can fly it. Like a motorbike it will regularly splatter people across the tarmac, but when it does, it will be even more cool!