Helicopter individual blade control system

An individual rotor blade control device for a helicopter main rotor (2) having a rotor shaft (4) driven by a main drive, with an even number of at least four rotor blades (8, 10, 12, 14, 16, 18) evenly distributed on the periphery of a rotor hub (6), comprising a primary control means (20) for collective and sinusoidal, cyclic rotor blade adjustment, which includes a transfer element for the control movements from a non-rotating system to a rotating system and actuators (36, 38, 40, 42, 44, 46) individually allocated one to each rotor blade (8, 10, 12, 14, 16, 18), wherein actuator control movement is superimposed onto the control movement of the primary control means (20) and each actuator is equipped with a safety device (54, 56) to bring the actuator into its final position and keep it there, if necessary, wherein half the rotor blades (8, 12, 16) are assigned to a first group of rotor blades and half the rotor blades (10, 14, 18) are assigned to a second group of rotor blades, the actuators when secured in their final positions provide angle changes of the first group of rotor blades (8, 12, 16) opposite in direction to the blade angle changes of the second group of rotor blades (10, 14, 18), and that each said group of rotor blades consists of at least two sub-groups (8, 12, 16;

• 10, 14, 18) evenly distributed on the periphery, with adjacent sub-groups being allocated to different said groups.