A remotely controllable flying machine, such as a remote control ultralight helicopter, has at least one rotor blade (104), the pitch (.alpha.) of which may be adjusted. The adjustment of the pitch (.alpha.) of the at least one rotor blade is achieved by means of a force, such as a torsion force directly applied to the rotation axis of the rotor blade. The force is generated by a magnetic field, variable by the electrical control of at least one coil (196) which is not part of an electric motor.