Interest in aeronavigational instruments arose with the demonstration of the military potential of aviation during World War I, and built slowly in the 1920s. The introduction of commercial transoceanic flights in the mid-1930s, together with growing international unrest, led to increased attention to this technology. The military services purchased large numbers of these instruments in the early years of World War II, and again during the Cold War, as did commercial airlines in the post war period.
With a marine sextant, the observer brings the image of a celestial body into coincidence with the actual horizon. Similar instruments designed for aeronautical use are equipped with an artificial horizon of one sort or another. Most of these instruments measure angles up to 90o but are referred to as sextants nonetheless.Materializing the Military (London, 2005), pp. 95-120.