The Slovak National Uprising, organized by Slovak military resistance, began in unfavourable conditions on August 29, 1944. In the first few days the insurgents lost major airfields in Piešťany, Spišská Nová Ves, Poprad, Vajnory near Bratislava and Trenčín, but they kept a large area in central Slovakia with Tri Duby airfield and a temporary airstrip near Zolná. All military aircraft of the insurgents' air force formed a reconnaissance-bomber unit, called the Combined Squadron. It consisted of four Avia B-534 biplane fighters, three older Letov Š-328light bombers, and two obsolete Bf 109E-4. They were later reinforced by a two other Bf 109G-6s and one Focke-Wulf Fw 189, which escaped from eastern Slovakia to the Soviets in Poland, after the insurgents in eastern Slovakia were surrounded and disarmed by Germans. Other aircraft reported in hands of rebels were two Klemm Kl 35, some Heinkel He 72 Kadett and two Savoia-Marchetti SM.84 medium bombers, captured during combat. The insurgents had trouble supplying their air force, especially ammunition for the German machine-guns of the Bf 109s. The Soviets provided help for the uprising on 17 September 1944, when they moved the 1st Czechoslovak Fighter Air Regiment under the command of Captain František Fajtl. This unit, flying Lavochkin La-5FN, was formed from among skilled fighter pilots - particularly Czechoslovak volunteer veterans from the RAF. Insurgent pilots flew 923 sorties and destroyed 40 Axis planes. They also provided many reconnaissance flights and attacks on ground targets. The activity of air forces in Slovakia at the end of 1944 was often disrupted by poor weather and low cloud, which made flights in mountainous central Slovakia very risky. Units provided air cover for the uprising from the Zolná and Tri Duby airfields until 25 October 1944. In these days the last insurgent airfield Tri Duby was threatened by artillery fire and the advance of German troops. As the uprising was being overrun by the Germans in the end of October 1944, the commander-in-chief of the insurgent army, Rudolf Viest, ordered the Air Force to withdraw from central Slovakia to safer airfields, secured by Red Army in Poland. Most of the pilots joined the 1st Czechoslovak Combined Air Division, which took part in liberating Poland and Czechoslovakia at the beginning of 1945.
