Brief History:

Following the breakup of the Austro-Hungarian Empire, a German-Austrian Flying Troop (Deutschösterreichische Fliegertruppe) was founded as an air policing service, with ex-wartime crews and aircraft. In 1919 the DF was ordered to be disbanded by the Allied Control Commission. On 1 April 1936 the Austrian Republic regained full sovereignty, although it was still prohibited from having any military aircraft. Even so, the Austrian Army quickly set up an Air Force. On 13 March 1938 Austria was incorporated into Germany, and the Air Force merged with the Luftwaffe. On 15 May 1955 Austria was re-established as a sovereign state. The present Air Force was formed in the same year

Source: http://www.aeroflight.co.uk/waf/austria/oesaf2.htm