Unit identification aircraft markings

USAAF unit identification aircraft markings, commonly called "tail markings" after their most frequent location, were numbers, letters, geometric symbols, and colors painted onto the tails (vertical stabilizer fins, rudders and horizontal surfaces), wings, or fuselages of the aircraft of the United States Army Air Forces during the Second World War. The purpose of these markings was to provide a visual means to rapidly identify the unit to which an aircraft was assigned. Variations of these markings continue to be used in the United States Air Force (USAAF) in the form of tail codes and color bands identifying operational wings.

Before World War Two the US had long used colorful unit marking on both its Army and Navy aircraft. In mid to late 1941, both services increased the use of camouflage colors and decreased its use of colorful markings. Tail designators on Army planes standardized on a radio call number (RCN) derived from the military serial number. Some aircraft were identified by numbers painted on their fuselage. Local radio procedures sometimes added additional numbers or lettering somewhere visible on the aircraft.

In the United Kingdom, the USAAF quickly adopted the system used by the Royal Air Force to identify squadrons, using fuselage codes of two letters (later letter-numeral when squadrons became too numerous) to denote a squadron and a third single letter to identify the aircraft within the squadron. Other areas continued to use only the RCN or simple numbering and lettering.

As the buildup of troops continued in the European Theater of Operations, the USAAF bomber formations grew and assembly necessitated better visual unit identification at greater distance.

To facilitate control among thousands of bombers, the USAAF devised a system of aircraft tail markings in 1943 to identify groups and wings. Both the Eighth and Fifteenth Air Forces used a system of large, readily-identifiable geometric symbols combined with alphanumerics to designate groups when all USAAF bombers were painted olive drab in color, but as unpainted ("natural metal finish") aircraft became policy at the start of 1944, the system evolved gradually to one using large areas of color in conjunction with symbols or patterns of color identifying the wing and often different colors for the group.

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