A multirotor or multicopter is a rotorcraft with more than two rotors. Multirotors often use fixed-pitch blades, whose rotor pitch does not vary as the blades rotate; control of vehicle motion is achieved by varying the relative speed of each rotor to change the thrust and torque produced by each.
Due to their ease of both construction and control, multirotor aircraft are frequently used as amateur model aircraft projects.
The e-volo is a prototype electric multicopter with 16 rotors, the first electric multicopter in the world to achieve manned flight. The large number of rotors make it economical, quiet and provide redundancy.
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