The 2K22 Tunguska (Russian: 2К22 "Тунгуска"; English: Tunguska) is a Russian tracked self-propelled anti-aircraft weapon armed with a surface-to-air gun and missile system. It is designed to provide day and night protection for infantry and tank regiments against low-flying aircraft, helicopters, and cruise missiles in all weather conditions. Its NATO reporting name is SA-19 "Grison".

Development of the 2K22 anti-aircraft system began on 8 June 1970. At the request of the Soviet Ministry of Defence, the KBP Instrument Design Bureau in Tula, under the guidance of the appointed Chief Designer A. G. Shipunov, started work on a 30mm anti-aircraft system as a replacement for the 23mm ZSU-23-4.^[4]


The project, code-named "Tunguska", was undertaken to improve on the observed shortcomings of the ZSU-23-4 (short range and no early warning) and a counter to new ground attack aircraft in development, such as the A-10 Thunderbolt II, which was designed to be highly resistant to 23 mm cannons.^[5] Studies were conducted and demonstrated that a 30 mm cannon would require from a third to a half of the number of shells that the 23 mm cannon of the ZSU-23-4 would need to destroy a given target, and that firing at a MiG-17 (or similarly at, in case of war, NATO's Hawker Hunter or Fiat G.91) flying at 300 m/s, with an identical mass of 30 mm projectiles would result in a kill probability 1.5 times greater than with 23 mm projectiles. An increase in the maximum engagement altitude from 2,000 to 4,000 m and increased effectiveness when engaging lightly armoured ground targets were also cited.^[6]


The initial requirements set for the system were to achieve twice the performance in terms of range, altitude and combat effectiveness of the ZSU-23-4, additionally the system should have a reaction time no greater than 10 seconds.^[4] Due to the similarities in the fire control of artillery and missiles, it was decided that the Tunguska would be a combined gun and missile system.^[4] A combined system is more effective than the ZSU-23-4, engaging targets at long-range with missiles, and shorter range targets with guns.


In addition to KBP as the primary contractor, other members of the Soviet military-industrial complex were involved in the project; the chassis was developed at the Minsk tractor factory, the radio equipment at theUlyanovsk Mechanical Factory, central computer at NIEMI ("Antey"), guidance and navigational systems by VNII "Signal", and optics were developed by the Leningrad Optical Mechanical Association (LOMO).^[7]


However, development was slowed between 1975 and 1977 after the introduction of the 9K33 Osa missile system, which seemed to fill the same requirement but with greater missile performance. After some considerable debate, it was felt that a purely missile-based system would not be as effective at dealing with very low flying attack helicopters attacking at short range with no warning as had been proven so successful in the 1973 Arab-Israeli War. Since the reaction time of a gun system is around 8–10 seconds, compared to approximately 30 seconds for a missile-based system, development was restarted.^[6]


The initial designs were completed in 1973, with pilot production completed in 1976 at the Ulyanovsk Mechanical Factory.^[4] System testing and trials were conducted between September 1980 and December 1981 on the Donguzskiy range.^[4] It was officially accepted into service on 8 September 1982 and the initial version, which was designated 2K22/2S6, had four missiles in the ready to fire position (two on each side). The Tunguska entered into limited service from 1984, when the first batteries were delivered to the army.^[4]


After a limited production run of the original 2K22, an improved version designated 2K22M/2S6M entered service in 1990.^[4] The 2K22M featured several improvements with eight ready-to-fire missiles (four on each side) as well as modifications to the fire control programs, missiles and the general reliability of the system.


Tunguska underwent further improvement when, in 2003, the Russian armed forces accepted the Tunguska-M1 or 2K22M1 into service.^[4] The M1 introduced the new 9M311-M1 missile, which made a number of changes allowing the 2K22M1 to engage small targets like cruise missiles by replacing the eight-beam laser proximity fuze with a radio fuse. An additional modification afforded greater resistance to infrared countermeasures by replacing the missile tracking flare with a pulsed IR beacon. Other improvements included an increased missile range from 8 to 10 km, improved optical tracking and accuracy, improved fire control co-ordination between components of a battery and the command post. Overall, the Tunguska-M1 has a combat efficiency 1.3–1.5 times greater than the Tunguska-M.^[8]


The Tunguska family was until recently a unique and highly competitive weapons system, though in 2007 the Pantsir gun and missile system entered production at KBP^[9]—a descendant of the Tunguska, the Pantsir system offers even greater performance than its predecessor.