The term roundel
is used in modern times to refer to insignia
markings on military aircraft
. As in the heraldic use, a roundel is a circular design, usually but not always with features of concentric rings of varying colors, used to identify the nationality and/or service of a military aircraft. These were first seen in World War I
, when military aircraft sported them on the top and bottom of their outboard wing edges so that the aircraft could be distinguished from their opponents in close battle, or by ground-based gunners. They were also placed on the vertical stabilizer
, and on either side of the fuselage
aft of the cockpit
They have remained in use to the modern day. Some militaries use more complex insignia, and the base roundel has been modified by additional elements - for example, while in WW2 the Japanese and English used classic roundels for identification, the U.S. military - after deciding in 1943 that the biggest differentiator for recognition wasn't the color but shape - added a rectangular white banner to theirs. The German Luftwaffe used a Balkenkreuz (beam cross, or bar cross as it consisted of straight lines unlike the Iron Cross of WWI) insignia, without the roundel component.