Acronym for Aircraft Report. AIREPs are messages from an aircraft to a ground station. These reports describe weather conditions in the upper layers of the atmosphere. AIREPs are normally comprised of the aircraft's position, time, flight level, ETA over its next reporting point, destination ETA, fuel remaining, and meteorological information. Usually reported at intervals of 10 deg longitude. Used primarily by airline class aircraft due to the increased tendency of these aircraft to fly at higher atltitudes (i.e. better fuel efficiency).