An air force ensign is a flag used by a national air force.
With the creation of independent air forces in the first half of the 20th century, a range of distinguishing flags and ensigns were adopted.[1] Such flags may often feature a roundel in the national colours.[2]
Notable examples include:
Some countries, such as the United States, designate their national air force standards as flags not ensigns. See the Flag of the United States Air Force for an example.