Military aircraft insignia

The first use of national insignia on military aircraft was before the First World War by the French Aéronautique Militaire, which mandated the application of roundels in 1912.

The Imperial German Army's mobilisation led to orders in September 1914 to paint all-black Eisernes Kreuz (iron cross) insignia with wide-flared arms over a white field; usually square in shape, on the wings and tails of all aircraft flown by its air arm, then known as the Fliegertruppe des Deutschen Kaiserreiches.

The form and location of the initial cross was largely up to the painter, which led to considerable variation, and even to the white portion being omitted.

With the dissolution of the German Army's Luftstreitkräfte in May 1920, military insignia would disappear until the rise of the Nazi Party, which imposed new rules on aircraft in 1937, starting with the use of the German red / white / black flag on the tails' starboard side of all aircraft, with the port side showing a Nazi Party flag.

When camouflage was introduced prior to the invasion of Poland, the flags were dispensed with, replacing them with a black and white swastika on both sides of the tail.

The British Royal Flying Corps (RFC) abandoned their original painted Union Flags because, from a distance, they looked too much like the Eisernes Kreuz (Iron Cross) used on German aircraft.

In the later stages of the World War I, the British Royal Flying Corps started using roundels without conspicuous white circles on night-flying aircraft, such as the Handley Page O/400.

These have subdued, low-contrast colours (often shades of grey or black), and frequently take the form of stencilled outlines.

The World War II German Luftwaffe often used such 'low-visibility' versions of their national Balkenkreuz insignia from the mid-war period through to V-E Day, omitting the central black 'core' cross, and only using the 'flanks' of the cross instead, in either black or white versions, which was often done (as an outline only) to the vertical fin or rudder's swastika as well.