Patent ID: 8447446

Claim:
A method for detecting an erroneous speed of an aircraft, provided by an on-board air data and inertial data measuring system ( 3 ), said measurement system ( 3 ) being able to generate and to provide in real time an air speed and a conventional speed, comprising, automatically: A/ performing the following operations: a) an air speed and a conventional speed are periodically memorized, being received from said measurement system ( 3 ); b) by means of said on-board sources of information being distinct from said measurement system ( 3 ), values of auxiliary parameters relating to the aircraft are measured; c) by means of said measured values, the drag and the thrust of the aircraft are estimated; d) by means of said estimated drag and thrust and said memorized air and conventional speeds, a theoretical air speed is calculated through an integration, taking into account an equation of the propelling balance of the aircraft; and e) by means of said theoretical air speed, said theoretical conventional speed is estimated; and B/ for each thus estimated theoretical conventional speed, during a predetermined period, the current conventional speed generated by said measurement system ( 3 ) is compared with such an estimated theoretical conventional speed, and an erroneous speed is detected in case of a mismatch between said current and estimated conventional speeds.