Stabilizing and directional-control surface of aircraft

1. A stabilizing and directional-control surface of an aircraft, comprising:

a vertical stabilizer; and

a rudder that deflects relative to the vertical stabilizer, the rudder including an internal profile that is extendable and retractable by an actuating system, wherein

an aerodynamic control surface area of the rudder is increased when the internal profile of the rudder is extended as compared to the aerodynamic control surface area of the rudder when the internal profile of the rudder is retracted, and

an outer surface of the rudder opens to permit the extension of the internal profile of the rudder and closes once the internal profile is fully extended.

2. The stabilizing and directional-control surface of an aircraft according to claim 1 , wherein the internal profile is extendable and retractable by the actuating system in a direction of a longitudinal axis of the rudder.

3. The stabilizing and directional-control surface of an aircraft according to claim 1 or 2 , wherein

the rudder with the extended internal profile forms a structure that preserves the rudder's properties of aerodynamic surface and continuity of flow.

4. The stabilizing and directional-control surface of an aircraft according to claim 3 , wherein the outer surface of the rudder is made of an alloy of a shape memory alloy (SMA) type.

5. The stabilizing and directional-control surface of an aircraft according to claim 3 , wherein the outer surface of the rudder opens along its longitudinal axis to approximately 75% of a geometric chord of the rudder from a trailing edge of a retracted position thereof.

6. The stabilizing and directional-control surface of an aircraft according to claim 5 , wherein the outer surface of the rudder includes two parts that open on a basis of rotation about two hinges, by way of two actuators.

7. The stabilizing and directional-control surface of an aircraft according to claim 1 , wherein the actuating system includes at least one actuator anchored to the rudder by way of a fitting and to the internal profile of the rudder by way of a catch.

8. The stabilizing and directional-control surface of an aircraft according to claim 1 , wherein the actuating system includes an elastic system.

9. The stabilizing and directional-control surface of an aircraft according to claim 1 , further comprising a guidance system that guides longitudinal movement of the internal profile of the rudder to ensure correct movement of the internal profile in conditions that require aerodynamic loads on the rudder.

10. The stabilizing and directional-control surface of an aircraft according to claim 9 , wherein

the guidance system includes a system of bearings and a bar, and

the bar is connected to the internal profile to guide the movement of the internal profile by the system of bearings to allow a single motion of the bar and the internal profile along a longitudinal axis of the rudder when the actuating system induces a translational motion on the internal profile.

11. The stabilizing and directional-control surface of an aircraft according to claim 1 , wherein

the actuating system includes a cable-controlled movement system, and

the cable-controlled movement system includes a cable connected to the internal profile and a motor with a cable take-up system that is anchored to the rudder.

12. The stabilizing and directional-control surface of an aircraft according to claim 1 , wherein

the actuating system includes a pyrotechnic system that includes a pyrotechnic device that breaks a pyrotechnic breaking cable connected between the internal profile and the rudder.

13. The stabilizing and directional-control surface of an aircraft according to claim 12 , wherein the pyrotechnic system is single-use and required to be replaced following an activation of the actuating system.

14. The stabilizing and directional-control surface of an aircraft according to claim 1 , wherein the internal profile includes two grooves in a surface thereof that help to maintain continuity of flow on the rudder when the internal profile is extended.