Method for diagnosing a state of deterioration of an uplock

A method for diagnosing a state of deterioration of an uplock for the retention of a tapped nut of a movable element, the uplock comprising:

• a hook pivoting between a release position and a retaining position that retains the tapped nut;
• a locking member pivoting between a locking position, in which the hook is immobilized in the retaining position by the locking member, and an unlocking position, in which the hook is free to be moved under a thrust of the tapped nut of the movable element;
• and
• an unlocking actuator comprising a hydraulic cylinder configured to act on the locking member in view of pushing it back to the unlocking position;
• the method comprising, during a release sequence of the hook immobilised immobilized in the retaining position by the locking member, the following steps:
• a) supplying the cylinder with pressurized fluid with an evolution law according to which the pressure of the fluid is, for a predetermined period, lower than a full pressure, then equal to the full pressure;
• b) determining a release time of the hook and comparing the release time with a time when the predetermined time period ends;
• and
• c) deducing, from the comparison performed in step b), a state of deterioration of the uplock.