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.
[3] 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 and the AH-64 Apache, which were designed to be highly resistant to 23 mm cannons.
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 the Ulyanovsk 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).
[3] 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) and two 2A38 autocannons.
An additional modification afforded greater resistance to infrared countermeasures by replacing the missile tracking flare with a pulsed IR beacon.
[3] A complete system or battery consists of six 2S6 combat vehicles armed with the 9M311 "Treugol'nik" (triangle) surface-to-air missile and two 2A38 30 mm cannons.
[9][10] The 2S6 combat vehicle uses the GM-352 and later GM-352M chassis developed and produced by the Minsk Tractor Plant (MTZ) which has six road wheels with hydropneumatic suspension on each side, a drive sprocket at the rear and three return rollers.
[9][11] an automatic gear change and diagnostic capability are available with latest Tunguska-M1 which uses the new GM-5975 chassis developed and produced by MMZ.
[12][13] Overall, the layout is similar to the previous ZSU-23-4 with a large central 360-degree rotating turret (designated the 2A40) containing the armament, sensors and three of the crew: the commander, gunner and radar operator.
[citation needed] An electromechanically scanned parabolic E-band (10 kW power) target acquisition radar is mounted on the rear top of the turret that when combined with the turret front mounted J-band (150 kW power) monopulse tracking radar forms the 1RL144 (NATO:Hot Shot) pulse-Doppler 3D radar[14] system, which can detect and track targets flying as high as 3,500 metres (11,500 ft).
[15][16] The radar system is highly protected against various types of interference, and can work if there are mountains on the horizon, regardless of the background.
[10] A battery of six Tunguska can automatically receive fire control information via an encrypted radio link, this allows targets to be distributed between individual units from a Ranzhir or PPRU battery command post, which can receive target information from either AWACS or early warning radar or in the case of the PPRU its own radar equipment.
HE-T and HE-I shells are used and fitted with an A-670 time and impact fuze which includes an arming delay and self destruct mechanism.
In optical mode, the gunner tracks the target through the 1A29 stabilized sight, with the radar providing range data.
[22][23] The system uses the same 9M311 (NATO: SA-19/SA-N-11) missile family as the naval CIWS Kashtan which can engage targets at a range of 1.5 to 8 kilometres (0.93 to 4.97 mi) and to an altitude of 5 to 3,500 metres (16 to 11,483 ft)[5] the Tunguska-M1 uses the improved 9M311-M1 missile with an increased range of 2.5 to 10 kilometres (1.6 to 6.2 mi) and an altitude of 15 to 3,500 metres (49 to 11,483 ft).
Once the missile is steered to within 5 metres (16 ft) of the target, an active laser or radio fuse (9M311-M1) is triggered.
[5] Variants of the 2K22 system have continued to serve in the Soviet and later Russian armed forces since their initial introduction in 1984.