PZL.56 Kania (buzzard) was a Polish pre-war initial project of a fighter aircraft designed by of the PZL works. A single-seat low-wing monoplane was a development of PZL.50 Jastrząb fighter, modified to house a new Hispano-Suiza 12Y engine, then under development in France. Jakimiuk was also responsible for development work on the PZL 11 fighter that equipped front line Polish squadrons in September, 1939, and after the war was a member of the de Havilland Canada team that designed the successful Beaver and Chipmunk bush planes.