Antonov State Enterprise, formerly the Aeronautical Scientific-Technical Complex named Antonov, 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 aeroplanes and aeroplanes using unprepared runways. Antonov has built a total of approximately 22,000 aircraft, and thousands of its planes are currently operating in the former Soviet Union and in developing countries.