The term scout, as a description of a class of military aircraft, came into use shortly before the First World War, and initially referred to a fast, light (usually single-seat) unarmed reconnaissance aircraft. "Scout" types were generally adaptations of pre-war racing aircraft – although at least one (the Royal Aircraft Factory S.E.2) was specifically designed for the role. At this stage the possibility of air-to-air combat was considered highly speculative, and the speed of these aircraft relative to their contemporaries was seen as an advantage in gaining immunity from ground fire and in the ability to deliver timely reconnaissance reports.