Multirotor

Multirotor
e-volo, the first manned electronic multirotor

A multirotor^[1] or multicopter is a rotorcraft with more than two rotors. An advantage of multirotor aircraft is the simpler rotor mechanics required for flight control. Unlike single- and double-rotor helicopters which use complex variable pitch rotors whose pitch varies as the blade rotates for flight stability and control, multirotors often use fixed-pitch blades; 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 in model and radio control aircraft projects^{[2][3][4][5][6][7]} in which the names quadcopter, hexacopter and octocopter are frequently used to refer to 4-, 6- and 8-rotor helicopters, respectively.

Hexacopter.^[8]

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.^[9]
• e-volo - a German prototype electric multicopter with 16 rotors, the first electric multicopter in the world to achieve manned flight.^[10][11] 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.^[12]

References

Wikimedia Commons has media related to Rotorcraft.