Black Knight Transformer Multicopter By Advanced Tactics

Examples
• Cierva Air Horse - a British three-rotor "heavy lift" helicopter first flying in 1948. Three rotors were used to give a large lift without compromising rotor strength.
• e-volo - a German prototype electric multicopter with 16 rotors, the first electric multicopter in the world to achieve manned flight. The large number of low-cost motors make it economical, quiet and provide redundancy with ability to maintain control with up to four failed motors.