OKB is a transliteration of the Russian initials of "" – , meaning 'experiment and design bureau'. During the Soviet era, OKBs were closed institutions working on design and prototyping of advanced technology, usually for military applications. The english language corresponding term for such bureau's occupation is Research and Development. A bureau was officially identified by a number, and often semi-officially by the name of its lead designer – for example, OKB-51 was led by Pavel Sukhoi, and it eventually became known as the OKB of Sukhoi. Successful and famous bureaus often retained this name even after the death or replacement of their designers. These relatively small, state-run organisations were not intended for the mass production of aircraft, rockets, or other vehicles or equipment which they designed. However, they usually had the facilities and resources to construct prototypes. Designs accepted by the state were then assigned to factories for mass production. After the collapse of the Soviet Union, many OKBs became Scientific Production Organizations () (NPO). There were some attempts to merge them in the 1990s, and there were widespread amalgamations in 2001–2006 to create "national champions", such as Almaz-Antey to consolidate SAM development. OKBs in aerospace industry KB-1 – NPO Almaz, Vitaly Shabanov OKB-1 – Korolev (today RSC Energia) OKB-1 – Dr. Brunolf Baade disbanded by 1953 OKB-2 – early name of MKB Raduga (OKB-155-2) OKB-3 – Bratukhin OKB-4 – Matus Bisnovat's Design Bureau (different from NPO Molniya) OKB-8 – Novator (long-range SAMs) OKB-19 – Shvetsov, Soloviev. Now: "Perm MKB" OKB-20 – Klimov, Omsk-Motors OKB-21 – Alexeyev OKB-23 – Myasishchev (also OKB-482) OKB-24 – Mikulin OKB-26 – Klimov OKB-39 – Ilyushin OKB-45 – Klimov OKB-47 – Yakovlev originally, transferred to Shcherbakov OKB-49 – Beriev OKB-51 – Sukhoi OKB-52 – Chelomei OKB-86 – Bartini OKB-115 – Yakovlev OKB-117 – Klimov, Izotov OKB-120 – Zhdanov (surname) OKB-124 – N/A (cooling systems for Tu-121) OKB-134 – Vympel OKB-140 – N/A (first hydro-alcohol starter-generators for Tu-121) OKB-153 – Antonov OKB-154 – Kosberg, previously OKB-296 OKB-155 – Mikoyan (formerly Mikoyan-Gurevich) OKB-155-2 – (sometimes designated as OKB-2-155) OKB-155 spin-off in Dubna. Gurevich, Berezniak, Isaev... Now MKB Raduga. OKB-156 – Tupolev OKB-165 – Lyulka OKB-207 – Borovkov and Florov (Borovkov-Florov D, Borovkov-Florov I-207) OKB-240 – Yermolaev OKB-256 – Tsybin OKB-276 – Kuznetsov OKB-296 – renamed to OKB-154 in 1946 KB Khimavtomatika OKB-300 – Tumansky OKB-301 – Lavochkin OKB-329 – Mil SKB-385 – Makeev OKG-456 – Glushko