An aircraft (100) with a rotary wing (40) is equipped with a propulsion system (10). The aircraft (100) includes a rotating mast (50) that rotates the rotor wing (40). The propulsion system (10) includes a pole (20) mechanically connected to the rotating mast (50) of the aircraft (100), where at least one end of the pole (20) is equipped with a motor (30) configured to rotate the pole (20) around the axis of the rotating mast (50) in such a way that the rotation of the pole (20) can be used to rotate the rotating wing (40). At each end of the pole (20) is placed a motor group (30), where each motor group (30) includes a pair of counter-rotating propellers (32,32), said pair of counter-rotating propellers (32,32′) being arranged in such a way as to generate a rotational torque to rotate the pole (20).