Military aviation in free Poland started even before the officially recognised date of regaining independence (11 November 1918). Poland was under German and Austro-Hungarian occupation until the armistice, but the Poles started to take control as the Central Powers collapsed. Initially, the Polish air force consisted of mostly German and Austrian aircraft, left by former occupants or captured from them, mostly during the Greater Poland Uprising. These planes were first used by the Polish Air Force in the Polish-Ukrainian War in late 1918, during combat operations centered around the city of Lwów (now Lviv). On 2 November 1918 pilot Stefan Bastyr performed the first combat flight of Polish aircraft from Lviv.