Following the brief April War, the Germans had captured over 300 ex-VVKJ aircraft. They considered them to be of little use for the Luftwaffe, so it was decided to equip the ZNDH with an appropriate number of these aircraft. These aircraft, scattered in every corner of Yugoslavia, were then collected, minor damage repaired and stocks of fuel and spare parts stored at airfield workshops. Naturally, the majority of the aircraft were more or less damaged and action was undertaken to repair as many of them as possible. Former VVKJ pilots of Croatian background and other personnel of aeronautical specialty were approached and offered instant rehabilitation (most of them were in German POW camps), jobs and safety for their families.