Timepiece, particularly of the wristwatch (1) type, forming a navigational aid for aviators or navigators, including at least a bezel (46) and a ring (38) that are concentric, at least one of which rotates, the bezel (46) bearing first indications (48) corresponding to the speed of an aircraft, or respectively a boat, and the ring (38) bearing indications (50) relating to the heading correction to be applied in the event of a crosswind, a nomogram (58) for the heading correction calculation being added to the back of the watch (1) or to a separate card.