Zmaj Fizir FP - 2 Aircraft Zmaj Fizir FP - 2 ( Serbian Cyrillic : Змај Физир ФП - 2 ) was a Yugoslav single - engine , two - seater biplane . It was designed by R . Fizir and D . Stankov built at the Factory " Zmaj " in Zemun in 1936 . Design and development . In 1933 , the command of the Yugoslav Royal Air Force ( YRAF ) decided to replace outdated planes with modern school aircraft , for transitional training from basic training to combat . Zmaj Factory designed a prototype biplane , Fizir FP - 1 , in 1993 for transitional pilot training , but it did not satisfy all the requirements set by the YRAF . As a result , aircraft designers and engineers , Rudolf Fizir and Dušan Stankov , made adjustments to the Fizir FP - 1 and so the plane became the , Zmaj Fizir FP - 2 . The designers opted for the concept aircraft biplane , although the YRAF preferred an aircraft with one low wing ( due to the development of modern combat aircraft ) . In the end , the concept of a new transitional school aircraft was accepted . Prototype Zmaj Fizir FP - 2 ( Fizir Prelazni ) with a Gnome - Rhone K - 7 engine of 308 kW power was completed and test flown at the end of 1933 . More test flights followed , and by 1934 the plane showed good results . The Zmaj modified the FP - 2 during 1934 using a Walter Pollux 2 engine of 235 kW power , but the results were not satisfactory . The Zmaj Fizir FP - 2 was a two - seater single - engine biplane aircraft , with air - cooled , 7 cylinder radial engine ( Gnome - Rhone K - 7 308 kW ) , and a pair of struts on each side . It had flaps on the upper and lower wings . Landing gear is fixed to a shaft , and deployment uses a rubber rope . Fuselage and wings were wood covered with canvas . The plane represented a classical " Yugoslav manufacturers ' school ' " - a two - seater , two wings , solid wood construction and polished aerodynamic shape , easy to fly , stable and reliable aircraft that is largely insensitive to pilot errors . On 22 May 1936 , the Zmaj factory offered the Navy a seaplane Zmaj Fizir FP - 2H with a Gnome - Rhone K - 9 engine , but the project was not accepted . Operational history . A total of 66 aircraft of this type were produced and served in the Yugoslav Royal Air Force from 1936 to 1941 . They were used for training military pilots . The first series of 20 of these aircraft were delivered to the YRAF in early 1936 and were immediately introduced into the first and second Pilot School . From 1938 to 1940 45 more aircraft were delivered . All three series aircraft were equipped the same , except the third series of five aircraft that were equipped to fly blind . These planes had a new pilot ' s panel and Zemun Teleoptik ( similar to the Rogožarski PVT ) . The fifth series Zmaj Fizir FP - 2 ( 15 copies ordered in 1940 ) was not completed by the start of the April war . At the beginning of 1943 the Germans were allowed to complete the fifth series aircraft Zmaj Fizir FP - 2 for the Croatian Air Force , but by 22 October 1944 ( Liberation Day Zemun ) only 8 aircraft were delivered . The last 7 aircraft were completed and handed over after the liberation of the Air Force for use by the Yugoslav Army . Thus the total number of Zmaj Fizir FP - 2 aircraft produced was 81 . Aircraft Zmaj Fizir FP - 2 in World War II . The Italians seized 13 Zmaj Fizir FP - 2 aircraft and with the Rogožarski PVT aircraft they were used from May 1941 to June 1943 against the rebels in Montenegro and Albania . The Germans seized 7 Zmaj Fizir FP - 2 at the Butmir airport and handed them over to their allies , the Croats ( NDH ) , which used them throughout the war , starting in 1941 . All planes of this type that survived the war were included in the Yugoslav Army Air Force ( RV JA ) and flew there until 1947 . The postwar registry included were 12 Zmaj Fizir FP - 2 planes . The remains of one of these planes are kept at the Museum of Yugoslav Aviation .