Avia B-534 in Bulgarian Service

Bulgaria ordered 78 Avia B-534 biplane fighters in 1939. These were obtained from Germany which had captured a large number of them. The final aircraft were not delivered until March 1942. At the same time, Bulgaria ordered more modern fighters such as the Messerschmitt Bf 109E and Dewoitine D.520, which resulted in the outdated B-534s seeing little frontline service. However on 1 August 1943, 48 Avias made several passes at Consolidated B-24 Liberators returning from the raid on Ploieşti. Although several hits were scored, none of the bombers were shot down.

Following the anti-German coup of 9 September 1944, Bulgaria switched sides after which the B-534s were used for ground attack.