Method and device for detecting an anomaly in the operation of an aircraft

A device to detect an operating anomaly in relation to reference values, of at least one component of an aircraft associated with at least one status indicator, said device—for at least two acquired time sequences each comprising successive acquired values of said at least one indicator at different instants throughout operation of said at least one component —comprising:

• a determination module, for each of said acquired time sequences, of an approximated time sequence comprising approximated values of said acquired values at said instants for this acquired time sequence, approximation being performed by an approximation module;
• a determination module, for each of said acquired time sequences, of a global anomaly score from differences between said acquired values and said approximated values for this acquired time sequence;
• and
• a detection module, for each of said acquired time sequences, of an operating anomaly of said component as a function of a comparison of said global anomaly score, determined for this sequence, with a first threshold, said approximation module previously being configured to minimize approximation errors between time sequences of reference values and time sequences of values approximated from said reference values, said reference values being representative of normal operation, such that approximation errors between said acquired values and said approximated values are greater if the acquired values are representative of abnormal operation, said second acquired time sequence being determined by sub-sampling said first acquired time sequence, said time sequence approximated from said acquired sequence being determined by said approximation module configured from reference time sequences of same sampling frequency as this acquired sequence.