Thanks Wahid - interesting! I can`t make out if the rotor blades are teetering type or individually hinged. I had wondered about making a teetering type hub for two blades but was advised against it as apparently this is less stable and less successful than the three bladed rotor system I (& most others) have used on my autogyros so far.
Question - Has anybody built a regular front engined wingless autogyro with a 2 blade rotor system with teetering rotors - or individually hinged rotors? What have the results been? Whichever 2 bladed method this Japanese model employs it seems successful. Any comments?