Abstract: A device for an aircraft moving in an air mass relative to a terrestrial frame of reference. The device can estimate at least one characteristic of a displacement of the air mass relative to the frame of reference. The device receives an element of information about the speed of the aircraft in the frame of reference, receives at least one element of information about the speed of the aircraft in the air, and obtains the characteristic from the speed information elements. The device is capable of receiving an element of information about the angle of attack (?) of the aircraft in the air, and is capable of determining the characteristic on the basis in particular of the angle of attack information element (?).

Abstract: A device is suitable as equipment in an aircraft moving in an air mass relative to a terrestrial frame of reference, in order to estimate at least one characteristic of a displacement of this air mass relative to this frame of reference. This device comprises first means for receiving an element of information about the speed of the aircraft in the frame of reference, second means for receiving at least one element of information (TAS) about the speed of the aircraft in the air, and third means for obtaining the said characteristic from the said speed information elements. The second means are capable of receiving an element of information about the angle of attack (?) of the aircraft in the air, and the third means are capable of determining the said characteristic on the basis in particular of the angle of attack information element (?).