At the time of the German invasion of Poland, nine PLZ.43As of the Bulgarian order were crated ready for delivery or were incomplete, two lacking propellors. Five were moved to the airfield at Bielany and taken over by the Polish Air Force for use by 41 "Eskadra Rozpoznawcza" (41st Reconnaissance Squadron) which was mostly equipped with PZL.23 Karaś. They undertook reconnaissance duties but by 10 September 1939, there were the only two aircraft remaining. One was shot down by a Messerschmitt Bf 110 at Michałówek near Sulejówek and the crew killed. The second, damaged by a pair of Messerschmitt Bf 109s, two days later, crash landed in Brześć. Both probably still carried Bulgarian markings.