From the planes used or shown in this picture the Soko 522 2-seat trainers, , Soko J-20 Kraguj and Utva 66 are post war models made in Jugoslavia. The Boing Stearman PT-17, Junkers Ju52/3m and Polikarpov Po-2W are actual WW2 planes. As the Kraguj has fixed gear, the "fighter" sequences in the movie look unusual, as the typical WW2 fighter had a retractable gear.