A flight control device of an aircraft including a support, an action member attached to the support rotating freely around a primary axis, a rotary device including a stator, rotatably connected to the support around a secondary axis, and a rotor rotating freely relative to the stator around the secondary axis, the rotary device applying a force sensing torque on the rotor relative to the stator around the secondary axis, and a mechanical reducing gear, which connects, with a reduction ratio, rotation of the action member with rotation of the rotor, the mechanical reducing gear including a screw-nut system with rolling elements, including a screw, attached to the rotor, connected in rotation to the rotor around the secondary axis, and a nut fixed in rotation around the secondary axis relative to the stator and helically connected with the screw around and along the secondary axis via the rolling elements.