2K11 Krug NATO reporting name: SA-4 "Ganef"
2K11 TEL in transit
Type	Transportable SAM system
Place of origin	Soviet Union
Service history
In service	1964–present
Used by	See list of operators
Production history
Designer	Lyulev Novator
Designed	1957
Manufacturer	MZiK
Variants	Krug, Krug-A, Krug-M, Krug-M1, Krug-M2, Krug-M3
Specifications (2K11 Krug[1])
Weight	28,200 kg
Length	7.5 m (9.46 m with missiles)
Width	3.2 m
Height	4.472 m (with missiles)
Crew	3 to 5
Armour	15 mm
Engine	V-59 V-12 water-cooled diesel 520 hp
Power/weight	17.33 hp/t
Ground clearance	0.44 m
Fuel capacity	850 litres
Operational range	780 km
Speed	35 km/h

The 2K11 Krug (Russian: 2К11 «Круг»; English: circle) is a Soviet and now Russian long range, medium-to-high altitude surface-to-air missile (SAM) system. "2K11" is its GRAU designation, while SA-4 Ganef is its NATO reporting name. The system was designed by NPO Novator and produced by Kalinin Machine Building Plant.

[edit] Development and service

Development of the Krug ZRK-SD (2K11) air defense system started in 1957 by the Lyulev OKB design bureau. It was first displayed during a parade in Moscow in May 1964. The system started to be fielded in 1967 and became fully operational in 1969. It was used by the Russian Army as a short-range SAM.

The early version of the Krug entered service in 1965. The first operational deployment version, the Krug-A, entered service in 1967, with extensively modified versions, the Krug-M in 1971 and the Krug-M1 in 1974, which were developed to rectify problems discovered during army service.^[1] The upgraded version Krug-M was fielded in 1971 and the Krug-M1 in 1974. A target drone called 9M316M Virazh, developed from obsolete Krug missiles, was proposed for export in 1994.^[2][3]

The 2K11 was briefly operated by the Soviet army during the war in Afghanistan in 1979 and 1980, but was withdrawn several months after the initial invasion.^[4] In 1997, it was reported^[2] that, between 1993 and 1996, some 27 fire units of Krug and 349 missiles had been sold to Armenia. Poland flight tested four missiles in September 2006 against P-15 Termit (SS-N-2 'Styx') targets.

The P-40 "Long Track" radar set.

[edit] Description

[edit] Vehicles

The TEL vehicles are tracked (modified AT-Ts) based on a GM-123 chassis and carry two missiles each on an elevating turntable for up to 360 degree rotation and 70 degree elevation. The two primary versions of the missile in service are the 9M8M1 (2K11M "Krug-M") and 9M8M2 (2K11M2/3 "Krug-M1"), both of which are believed to be known to the US DoD as SA-4B. The original 9M8M (SA-4A) was first introduced into service in 1965 and followed by the upgraded 9M8M1 (2K11A "Krug-A") in 1967 before the 9M8M1 in 1971 and the 9M8M2 in 1973. The 9M8M2 actually has a lower maximum engagement altitude and shorter range in exchange for better performance in engaging aircraft close to the battery. Each battery typically consists of two 9M8M1 missiles and four 9M8M2 missiles as well as the following radars:

• P-40 "Long Track" E-band early warning radar (also used by the SA-6 and SA-8, range 175 km/108 miles)
• "Pat Hand" H-band continuous wave fire control and guidance radar (range 128 km/80 miles)
• "Thin Skin" E-band height finding radar (also used by the SA-6 and SA-8, range 240 km/148 miles)

Both "Long Track" and "Pat Hand" are mounted on a modified AT-T vehicle, similar to the 9M8 launch vehicles. "Thin Skin" is mounted on a truck. Batteries may also feature Ural trucks carrying spare missiles for reloading the launchers.

[edit] Missile

9M8
Type	Surface-to-air missile
Place of origin	Soviet Union
Production history
Variants	3M8 (later 9M8) Krug, 9M8M Krug-M, 9M8M1 Krug-M1, 9M8M2 Krug-M2, 9M8M3 Krug-M3.
Specifications (9M331[1])
Weight	2,453 kg
Length	8.784 m
Diameter	86 cm
Warhead	Frag-HE
Warhead weight	150 kg
Detonation mechanism	contact and proximity fuzes
Propellant	kerosene fuelled ramjet
Operational range	55 kilometres (34 mi)
Flight altitude	24,500 metres (80,000 ft)
Boost time	four solid fuel booster rocket motors
Speed	1100 m/s
Guidance system	Radio command, semiactive radar

The missiles are launched with the aid of four solid fuel rocket motors inside boosters attached to the outside of the massive missile. Once they have burned and the missile is aloft, it fires a liquid-fuelled ramjet sustainer engine. It reaches speeds of up to Mach 4 and has an effective range of 50-55 km (31-34 miles) depending upon the version. It carries a 135 kg (300 lb) warhead. Possible engagement altitudes range from 100 m-27 km (330-88,500 feet). 3M8 missile was designed and produced by NPO Novator.

Missile guidance is via radio command with a terminal semi-active radar homing (SARH) phase. Optical tracking is possible for the initial command guidance stage in a heavy ECM environment.

The 9M8's enormous range makes it dangerous; however, the missiles are quite large and unlikely to hit small, maneuverable aircraft like fighter jets unless they are caught unaware.^{[citation needed]}

[edit] Structure of Krug missile system

• Self-propelled launch vehicle 2P24
• Rocket guidance station 1S32
• Target detection station 1S12
• Transporter-loader vehicle 2T6

[edit] Operators

[edit] Current operators

•  Armenia - 115^[1]
•  Azerbaijan^[1]
•  Bulgaria - 30^[1]
•  Poland - 30^[1]
•  Turkmenistan - 30^[1]
•  Kyrgyzstan^{[citation needed]}
•  North Korea - unknown number

[edit] Former operators

•  Czechoslovakia had 1 brigade. Phased out in early 1990s.
•  East Germany. Passed onto successor states.
•  Hungary had 1 regiment. Phased out in middle 1990s.
•  Russia - 500(phased out in 2007)

[edit] Notes

[edit] External links

Wikimedia Commons has media related to: 2K11 Krug

• SA-4 Ganef at Global Security website
• SA-4 Ganef at Federation of American Scientists website
• Photos of Polish Krug at Vestnik PVO website