Kingdom of Serbia became part of the new state, Kingdom of the Serbs, Croats and Slovenes. which was formed on 1 December 1918. Even though the industry was on a very low level of development, the state was among the first 10 countries in the world which developed their own aircraft production. Originally, only the parts produced in foreign factories were assembled, but very soon the production of domestic components began, so as the engineering. The forerunner of the domestic aircraft industry was the Airplane workshop (Aeroplanska radionica), which was established in 1920, at the airfield in Novi Sad. The assembling of the trial series of Hansa-Brandenburg C.I. The series was named SBr, as this type of plane was known in Serbia as srednji Brandenburg ("middle Brandenburg").
From 1923 to 1941, there were 7 aircraft factories in Serbia, 4 of which were located in the capital, Belgrade, and 2 airplane engines factories. Also, some planes were produced in the aircraft workshops, aero clubs and private workshops. There were also factories for the aircraft equipment and workshops for the repairs and overhauls of the aircraft, engines and components. A major boost to the industry was a decision by the state from 1926 to acquire over 800 fighters and several hundreds of trainers and school planes. Additional foreign licenses were obtained. The advance of the industry was halted in 1932 when the state stopped with the further acquirement of the aircraft due to the Great Depression. The production rebound from 1937 onwards.
According to the State union of the aircraft industries of the Kingdom of Yugoslavia, the state's aircraft industry and the auxiliary industries employed 300 engineers and technicians, 500 employees and 6,000 workers. In total, 1,729 military and civilian aircraft were produced in Serbia between two World Wars. Of those, none were cargo or reconnaissance aircraft. One of the most important people in the technical development of the aircraft design was engineer Milenko D. Mitrović "Spirta" (1905–1986), who developed numerous designs for the airplanes in the 1928-40 period.
Factories Ikarus (1923-62)
First proper factory was established on 20 November 1923 in Novi Sad. The driving force behind it foundation was Dimitrije Konjović, former pilot in the Austro-Hungary's air forces in World War I. He founded Ikarus together with brothers Dušan and Milivoj Kovačević and engineer . Jointly with the Rogožarski factory, founded a bit later, they were given a task of producing the trainer aircraft "ŠB" (školski Brandenburg, literally "school(ing) Brandenburg"). In April 1924 first planes were delivered while in November 1924 the factory produced the first homemade aircraft as the company's designing bureau drafted the trainer flying boat "ŠM" (školski mornarički, "school naval (plane)").
In 1927-28 Ikarus built new facilities in Zemun, equipped for the serial production of airplanes and its own airfield. By the end of 1932, the headquarters of the company also moved to Zemun. The production in Novi Sad was completely discontinued in 1932. In 1934 the town of Zemun was officially merged into Belgrade.
In the 1923-41 period, Ikarus produced a total of 441 aircraft. Some of the best aircraft produced in the factory include observation plane Potez XV, light bomber Bristol Blenheim and fighters Hawker Fury and Ikarus IK-2. It was the first company which began producing gliders, in 1928. They also constructed the first Serbian and Yugoslav fighter plane, completely domestically designed, IK-1, in 1935, designed by and .
Right after occupying Yugoslavia, Germans commandeered the factory on 17 April 1941. The complex was heavily bombed during the massive Allied Easter bombing of Belgrade in April 1944. The facilities of Ikarus were almost completely destroyed during the war, but the factory was rebuilt. In 1946 Zmaj and Rogožarski were merged with the Ikarus, after previously being nationalized. In 1954 the company began producing buses and, starting from 1960, the production of aircraft was being shut down and relocated to the SOKO factory in Mostar, Bosnia and Herzegovina. Production of the aircraft was completely discontinued in 1962 and, until that date, Ikarus produced a total of 475 planes after the war. The facilities were completely demolished and the area is today occupied by the residential buildings, stretching between the Hotel Jugoslavija on the east, and Palmira Toljatija Street (roughly blocks 9-A and 11-C. divided between the municipalities of Zemun and New Belgrade). The engineers and the design bureau were transferred to the Aeronautical Technical Institute in the Belgrade's suburb of Žarkovo. The company was ultimately renamed to Ikarbus.
Well known aircraft constructed in Ikarus after the war include fighter Ikarus S-49, trainers Ikarus 213 and Ikarus 522, light reconnaissance-bomber Ikarus 214 and baby twin-jet Ikarus 452M.
The administrative building of the company, which was built in 1938 as part of the complex, as of 2018 is one of the oldest surviving buildings in New Belgrade. In June 2017 it was announced that the building will be demolished so that private investor can build a highrise instead. Locals organized in an effort to adapt the building into the museum instead. In 2018 Citizen protested, demolished the construction hoarding and physically prevented the investor to destroy the building, so police intervened. Investor then posted a board which showed that the original building will be preserved but vastly expanded and superstructured. Still, a heavy demolition machinery was brought so citizens protested again in March. Inheritors of the pre-World War II owners of the "Ikarus" company, which was nationalized after 1945, applied for the restitution. The administrative building of the former airplane factory was a symbol of the industrial development of the Kingdom of Yugoslavia. Apart from being one of the oldest preserved objects in New Belgrade, it was the only representative of the Art Deco in the municipality. Citizens proposed that the building might be adapted into the Museum of New Belgrade or a branch of the Museum of Aviation. The building was not protected by the law. Still, the building was demolished in July 2018.
Rogožarski (1924-46)
Predecessor of the company was the Rogožarski carpentry workshop. It worked on the repairs of the confiscated airplanes in the World War I. In April 1924 the "First Serbian airplane factory Živojin Rogožarski" was founded in Belgrade by Živojin Rogožarski. At first, worked jointly with Ikarus on "ŠB". Due to the major financial losses, the company was taken over by the new owners in 1934. The Resavac and the Blagojević brothers transformed the company into the joint-stock company "Rogožarski A.D. Beograd" and the company was revived. It produced a total of 284 airplanes in the 1924-41 period, mostly designed locally.
Apart from the "ŠB", the best known aircraft manufactured in Rogožarski were trainers Fizir F1V and Rogožarski R-100, floatplane Rogožarski SIM-XIV-H and fighter Hawker Hurricane.
Rogožarski produced the IK-3 airplane, considered the finest Serbian fighter. It was a low-wing one-seat monoplane, constructed in 1936 by Ilić, Sivčev and Slobodan Zrnić. The prototype was finished in 1938 and the production began in 1940. Till the beginning of the World War II, in April 1941, only 12 airplanes were finished. Six were in service at 51st Independent Fighter Group of the 6th Fighter Aviation Regiment, which defended the capital Belgrade. They held their own against the Messerschmitt Bf 109 (Bf 109E) planes, during the German invasion. Three IK-3s were shot down, while 7 Messerschmitts were also gunned down and one was damaged. The three remaining IK-3s were destroyed by their crews on the ground, in order not to get captured by the advancing Germans.
The factory was located in the neighborhood of Palilula, bounded by the streets of Stanoja Glavaša, Dalmatinska, Starine Novaka and Kneza Danila. The new Communist authorities nationalized the company, merged it into Ikarus in 1946, while the facilities were transformed into the IKL (ball bearing factory) in 1948. The complex was demolished and in 2015 construction of the residential and commercial neighborhood of "Central Garden" began, which should include the 16-storey "Business Garden Tower".
Zmaj (1927-46)
In 1927 the "Zmaj" factory was established in Zemun. Full name was Fabrika aeroplana i hidroplana - Zmaj, Petrović i Šterić ("Airplane and flying boats factory Zmaj - Petrović & Šterić"). From the early 1930s the factory began producing the state's first training planes, training flying boats and the trainer fighter aircraft, using French design. During the 1927-41 period, 126 licensed (foreign designed) planes were produced, with additional 220 locally designed ones.
Production of the locally designed planes began in 1932. The factory produced, among others, fighters Hawker Hurricane, Hawker Fury and Dewoitine D.27, trainer Zmaj Fizir FP-2, and passenger transporter Spartan Cruiser for the Aeroput Air Traffic Society, the first air traffic company in Serbia and precursor of the modern Air Serbia.
After 1946, the company was adapted for the production of the agricultural machines, while the aircraft section was merged into Ikarus.
Brege / FAK (1927-42)
In 1924 the Air Force decided to build an aircraft factory for its own needs, deep inside the state's territory. In September 1926, on the Divlje Polje locality near Kraljevo, construction of the new plant for the construction and repair of the aircraft began, which was finished in 1927. According to the contract with the government, it was soon taken over by the French Breguet Aviation company, which used it for the production of the Breguet 19 airplane type. The factory was officially called Breguet Aeroplanska radionica u Kraljevu ("Breguet airplane workshop in Kraljevo"), but was colloquially known as FAK (Fabrika aviona Kraljevo, "Kraljevo airplane factory"). Production of Breguet 19 began in 1928 and 470 units were made, more planes than any other factory in this period. The production was halted in 1933 when the contract expired and the French withdrew from the business. Air and Technics Institute in Kraljevo (VTZ, Vazduhoplovno-tehnički zavod), took over the premises. In this period repairs were conducted and the spare parts were produced.
Production was revitalized in 1939 when the State airplane factory (DFA, Državna fabrika aviona) was founded. The production included the modern and more complex two-engine bombers Dornier Do 17K, on the German license. During the Kraljevo massacre in October 1941, among over 2,000 victims executed by the occupational German forces, there were 473 employees of the factory.
During the withdrawal in front of the invading German army, Royal Yugoslav Army destroyed the most vital parts of the plant and the Germans never managed to repair it, though they used it for occasional repairs of the Breguet and Dornier planes. Those little remaining machines and equipment which survived were dismantled in 1942 and transported to Germany. After the war, authorities didn't try to restore the plant, instead, what remained of it was attached to the "Kraljevo railway wagon factory" (FVK, Fabrika vagona Kraljevo).
Utva (1937)
The Glider Union "Utva" (Jedriličarska zadruga "Utva") was founded on 5 June 1937, also in Zemun. It produced only gliders until 1939 when it was transformed into the full aircraft factory "Utva" AD. In 1940 the factory was relocated to Pančevo where the German licensed Bücker Bü 131 (Bücker Jungmann) training aircraft were assembled. In Pančevo factory had its own airfield.