So What\'s Patentable here??
Weight shift helicopter, same as many ultralight helis made over the last 70 years.
Application of Electric Motors for spinning a Propeller, have to look at RC planes over the last 20 years.
Maybe he could patent a new way to cook Kebabs.
Shish, in the rotors, cooked via expliding Li-Po\'s.
Nice to see electrics getting air time.

I would have preffered to sit on a Lithium iron phosphate battery for its safety characteristics, the trade off on size and weight would be a small one in this application...

I would suggest using inflatable pontoons for the landing gear. This would save weight, and give a soft touchdown. I feel this project is going to struggle to get any endurance.
As far as helicopters being dangerous, we are always told that they can auto-rotate to touchdown if the engine fails. Does this ever happen? I am a fan of autogyros. Surely they are more efficient than helicopters? Slower admittedly.

Next goal for Helicopters - CLOCKWORK!
:D

\"Yaw control was achieved with a combination of electric controllers (presumably varying the speeds of the two rotors) and a mechanical linkage that tilts the tail fin against the downwash from the main rotors - and the yaw controls are operated through pedals as in a conventional helicopter design.\"
I doubt that the blade velocity can be varied between the two blades. More likely the blade pitch can be varied between the two blades. The blade with the higher pitch will exert more torque, causing the chopper to rotate about its vertical axis.

Terrific article, the best I\'ve read in gizmag for years.
I\'m a pilot, and the reason helicopter accident statistics are higher is actually the way they are used - not because of the helicopter.
Almost all heli accidents are from operational incidents like wire strikes, logging, Medevac and other extremely dangerous low-altitude ops. When you get down really low like helis have to, the wires, towers, antennas and trees seem to come out of nowhere.

That\'s fantastic. I just wish gizmag would let us know of the costs to develop such technology. I see he was commisioned. I have hopes of inventing things too, but have little money to invest in prototypes. I\'d like to know how much play money I would need to seriously think about inventing. So how much did this contraption cost? 100$, 1000$, 100000$, what power of ten are we talking here?

@IggyDalrymple-R/C co-ax helicopters do use differential speed between the blade sets to control yaw. I do not know if that is what is employed here; only that it is used in models quite successfully. It would seem that digital speed controls would be a much more economical and lighter approach.

\"Chretien chose brushed DC motors for the rotor shafts, even though the required power output was \"just on the edge of what can be achieved with brushed motors\" - because brushed motors are exceptionally efficient, and their simple controller units are significantly lighter than those of more powerful, less efficient brushless motors.\"
The article seems to have this backward. Brushless DC motors are much more efficient than brushed DC motors. The carbon brushes in the brushed motors add significant friction to the system which reduces efficiency and increases heat output. This is why all modern electric vehicles and RC cars and planes use brushless DC motors. Brushless DC motors do require much more complicated electronics, and they also tend to be more expensive.

@Bill. I was thinking the same exact thing when reading the article. I always replace brushed motors, with brushless in my RC planes & heli\'s, or outright purchase a brushless with a new machine.