Antonov State Company (Ukrainian: Державне підприємство "Антонов"), formerly the Antonov Aeronautical Scientific-Technical Complex (Antonov ASTC) (Ukrainian: Авіаційний науково-технічний комплекс імені Антонова, АНТК ім. Антонова), and earlier the Antonov Design Bureau, is a Ukrainian aircraft manufacturing and services company. Antonov's particular expertise is in the fields of very large airplanes and airplanes insensitive to runway quality. Antonov (model prefix An-) is the most common airplane brand on the planet, with total of 22,000 aircraft built and thousands of planes currently operating in the former Soviet Union and the developing countries. 

Antonov StC is a state-owned commercial company that established in 1946 in Novosibirsk as a top-secret Soviet Research and Design Bureau#153, headed by Oleg Antonov and specialized in turboprop military transport aircraft. The An-2 biplane is a major achievement of this period. In 1952, the Bureau was relocated to Kiev, a city with rich aviation history where aircraft-manufacturing infrastructure was being restored after the World War II destruction.

First serial aircraft and expansion

In 1957, the bureau successfully introduced the An-10/An-12 family of mid-range turboprop airplanes into mass production (thousands of aircraft were manufactured). The model have been seeing heavy combat and civil use around the globe to the present day, most notably in the Vietnam War, Soviet war in Afghanistan and the Chernobyl disaster relief megaoperation.

In 1959, the bureau began construction of the separate Flight Testing and Improvement Base in suburban Hostomel (now the Antonov Airport).

In 1965, the Antonov An-22 heavy military transport enters serial production, supplementing the An-12 in major military and humanitarian airlifts of the Soviet Union. The model became the first Soviet wide-body aircraft and remains the world's largest turboprop-powered aircraft to date. Antonov designed and presented a nuclear-powered version of the An-22 which, however, never entered flight testing phase.

In 1966, after major expansion in the Sviatoshyn neighborhood of the city, the company was renamed to another disguise name "Kiev Mechanical Plant". Two independent aircraft production and repair facilities, under engineering supervision of the Antonov Bureau, also appeared in Kiev during this period.

Prominence and Antonov's retirement

In 1970s and early 1980s, the company established itself as USSR's main designer of military transport aircraft with dozens of new modifications in development and production. After Oleg Antonov's death in 1984, the company is officially renamed as the Research and Design Bureau named after O.K. Antonov (Russian: Опытно-конструкторское бюро имени О.К. Антонова) while continuing the use of "Kiev Mechanical Plant" alias for some purposes.

Late Soviet-era: superlarge projects and first commercialization

In late 1980s, the Antonov Bureau achieved global prominence after introduction of its extra large airplanes. The An-124 "Ruslan" (1982) became Soviet Union's serial-produced strategic airlifter. The Bureau enlarged the "Ruslan" design even more for the Soviet space shuttle programme logistics, creating the An-225 "Mriya" in 1989. "Mriya" has since been the world's largest and heaviest airplane.

End of the Cold War and perestroyka allowed the Antonov's first step to commercialization and foreign expansion. In 1989, the Antonov Airlines subsidiary was created for its own aircraft maintenance and cargo projects.

Expansion to free market

Since independence, Antonov is busy with certifying and marketing of its models (both Soviet-era and newly-developed) to free commercial airplanes' markets. New models introduced to serial production and delivered to customers include the Antonov An-140, Antonov An-148 and Antonov An-158 regional airliners.

Production facilities' consolidation

During the Soviet period, not all Antonov-designed aircraft were manufactured by the company itself. This was a result of Soviet industrial strategy that split military production between different regions of the USSR to minimize potential war loss risks. As a result, Antonov airplanes are often assembled by the specialist contract manufacturers.

In 2009, the once-independent "Aviant" airplane-assembling plant in Kyiv became part of the Antonov State Company, facilitating a full serial manufacturing cycle of the company. However, the old tradition of co-manufacturing with contractors is continued, both with Soviet-time partners and with new licensees like Iran's HESA.