Abstract: A method for automatically detecting an erroneous height value supplied by a radio altimeter mounted on an aircraft. The method includes measuring, during the aircraft's approach phase with a view to landing, the duration between the times when a first predetermined altitude threshold and a second predetermined altitude threshold are reached. This duration is measured by taking into account current height values supplied by the radio altimeter. The method then includes comparing the measured duration to a predetermined duration reference time, which is lower than a flight duration that would allow the aircraft to descend from the first predetermined altitude threshold to the second predetermined altitude threshold at a maximum vertical speed. An erroneous height value is detected if the measured duration is lower than the predetermined duration reference time.

Abstract: Method and device for automatically determining an erroneous height value of a radio altimeter mounted on an aircraft. The device (1) includes means (12, 13, 15) for comparing the duration between two height thresholds to a predetermined reference time, by taking account of current height values of the radio altimeter (2), during an approach phase.