Method for detecting a blockage of at least one wind vane of an aircraft and associated system

A system for detecting a blockage of at least one in-flight angle-of-attack sensor of an aircraft, the system comprising:

• the in-flight angle-of-attack sensor, the in-flight angle-of-attack sensor being a wind vane and comprising a support, a paddle rotating relative to the support along a rotation axis, a motor configured to exert a rotational torque on the paddle along the rotation axis, the in-flight angle-of-attack sensor further comprises an angular sensor configured for measuring an angular position of the paddle around the rotation axis;
• a processing unit configured to command the motor so that the motor applies a predetermined blockage detection torque on the paddle;
• and
• a sensor for measuring information representative of a resistance of the paddle to the predetermined detection torque, the processing unit being configured to generate a blockage information signal of the in-flight angle-of-attack sensor, if a predetermined condition based on the information representative of the resistance of the paddle to the predetermined detection torque is verified
• wherein the processing unit is configured to acquire, before applying the predetermined blockage detection torque, an initial angular equilibrium position of the paddle,
• wherein verifying the predetermined condition comprises:
• acquiring, by the angular sensor, an imposed actual angular equilibrium position of the paddle subjected to the predetermined blockage detection torque by the motor, the information representative of the resistance being the imposed actual angular equilibrium position;
• calculating an actual angular misalignment between the imposed actual angular equilibrium position and the initial angular equilibrium position;
• and
• comparing the calculated actual angular misalignment to an angular threshold, the predetermined condition being verified if the calculated actual angular misalignment is below the angular threshold.