Many European countries have an eagle as the main charge of the heraldic shields of their respective monarchies: Germany, Austria-Hungary, and pre-revolutionary Russia all used some derivative of this bird in their badge.
During the Second World War, the air forces of Italy, the Netherlands, Greece, and Yugoslavia also used a bird of prey as their cap badge.
The countries of the Warsaw Pact during the Cold War generally rejected the use of the eagle in the list of state seals above.
For example, the Soviet air force used a vol very similar to the French, but supported a conventional, five-pointed star, so as to distinguish themselves from having anything to do with Imperial Russia.
Warsaw Pact armed forces often had a red, five-pointed star superimposed upon the juncture point of this symbol.
During the Second World War, the uniforms of Denmark, Norway, Belgium, France, Nationalist China, and even the RAF used a form of the vol as their pilot's insigne.
Specifically, the uniforms of both enlisted ranks and officers in the Deutsche Luftstreitkräfte (or East German Air Force) did too.
Both the terms 'vol' and 'demi vol' (half a vol, i.e. a single wing) have been turning up every so often in Scots heraldry since the late 17th century - Sir Thomas Brand's crest, 'a volle with the baton of his office [Knight Usher of the Green Rod] in pale', in the Scottish Public Register volume 1, page 123, and the crest of Richard Graham, Viscount of Prestoun, volume 1, page 84