LAW "Circle": photos, specifications, video
LAW "Circle": photos, specifications, video

LAW "Circle": photos, specifications, video

The Circle is a domestically produced anti-aircraft missile kit that was put into service in the 1965 year.


History of creation


In the year 1956, research was started on the possibility of creating a military air defense of army-front mission with the use of rocket technology. They were held on a competitive basis as part of research projects such as “Theme 2” and “Theme 3”. The main managers of these works are from SRI-20 - V.P. Efremov, holding the post of lead executor, from OKB-8 - L.V. Lyulyev and from TsNII-58 - V.G. Grabin (they were the leaders of the work).


By the middle of 1958, all co-contractors received technical tasks, and on the basis of the draft tactical and technical requirements, they adopted a resolution of the Council of Ministers of the USSR on the implementation of the ROC "Circle".


In winter, 1961 year after start-up confirmed the correct direction of the development of the complex. Then there was the beginning of the development of the components of the complex and the exit to the tests, which took place in the 3 stage.

At the first stage, we conducted factory tests according to the methodology and program of the head of the ROC.


On the second stage, we carried out joint state tests using methods developed by the test site.


At the third stage, periodic tests of serial samples were carried out. Between 1963 and 1964, state tests were passed.


In the winter of 1965 of the year by order of the USSR Ministry of Defense of the air defense system 1963 of the year to the summer of 1964 of the year. 3 February 1965 ordered by the USSR Ministry of Defense the “Krug” air defense system entered service with military air defense.

Photo 2

What are the requirements for the Krug air defense system?

  1. Intercept air targets that fly at speeds up to 600 meters per second at altitudes from 3000 to 25 000 meters.
  2. The probability of the destruction of aircraft in the air, such as the IL-72 front-line bomber at altitudes up to 20 000 meters, is not less than 80%.
  3. Target detection with an effective dispersion surface of the MiG-15 type fighter at a distance of at least 115 km.


It is worth noting that the government has set a tight time frame for developers. The first tests were to take place in the third quarter of 1961. As already noted, the project manager was appointed designer V.P. Efremova, who had already worked to improve the air defense and radar of the city of Moscow.


Tasks and Goals


The government approved the terms of reference in 1958. According to him, it was necessary to develop 2 new anti-aircraft guided missiles - 3М10 and 3М8, with mixed and command-type guidance, respectively.


The design team of OKB-8 was engaged in research in this direction under the strict guidance of S. Korolev, who later became part of OKB-2 (an experienced design bureau) under the authority of P. Grushin on the basis of the Central Research Institute-58.

Photo 3

In connection with the creation of new missiles, there was a need to develop new launch systems for anti-aircraft guided missiles, since the existing models simply did not pass in many respects. To shorten the development time and unify the details of the Krug air defense system, the Kub project being developed was used as a basis.


The composition of the anti-aircraft missile complex 2K11 "Circle"


Platoon control. Composition:

  • target detection station - 1 x 1C12;
  • target designation receiving cabin - 1 x 9С44 “Crab К-1” (starting from 1981, was replaced by 9СXNNXX “Poliana D-468”.


Three anti-aircraft missile batteries. Composition:

  • missile guidance station - 1 x 1С32;
  • self-propelled launcher - 3 x 2P24;
  • anti-aircraft guided missile (two for each 2P24 JV).

Photo 4

Technical battery. Composition:

  • control test station - 2B9 (several units);
  • transport vehicle - 9Т226 (several units);
  • transport-loading machine - 2Т6 (several units);
  • refueling machines;
  • equipment for the assembly and refueling of rockets.


Missile Detection and Guidance


The radar 1C12 was responsible for detecting the enemy. She found targets at an altitude of no more than 12 thousand meters at a distance of 180 km and at a distance of 70 km if the target height was less than 500 meters. After the station was detected by the enemy, she gave the targeting machine 1C32.


The main task of the missile guidance station is to search for targets using the information provided by the station for detection and target designation and tracking of the launched missiles. When the enemy is detected and after all the calculations made, the information was sent to the launchers, which were deployed in the necessary sector and proceeded to "shadowing." When the target entered the defeat zone, the induced missiles of the Krug anti-aircraft missile complex launched.


The released missiles captured the rays of the accompanying antennas, which corrected the trajectory and transmitted data for cocking the fuse and other commands.




As noted above, the simultaneous creation of 2 rockets — the 3М8 and 3М10 — was carried out, the first one becoming more successful. It was developed by the aerodynamic design of the "rotary wing" due to the unstable operation of power plants. Structurally, the rocket consisted of 2 stages:


  1. Marching, with an air jet engine that worked on kerosene fuel.
  2. Starting, with 4 self-separating accelerators operating on solid fuels.


The high-explosive warhead of the ZUR was located in the recessed central body of the air intake and had a weight of 150 kg. Here were homing head and an air battery with a balloon. Undermining was carried out using a radio fuse for 50 m to the target. The total weight of the rocket - 2,4 th. Kg. This anti-aircraft guided missile was used in all complexes of this series, incl. and in the Krug-M air defense system.


How is the launch of missiles?


The 2P24 launcher simultaneously performed several tasks — transporting missiles to the point of combat duty, guiding and launching missiles for detected or accompanied targets. She could simultaneously carry 2 absolutely ready to defeat the purpose of Zour. During start-up, the machine calculation is inside the SPU.

Photo 8

The rockets were on an arrow equipped with hydraulic cylinders, which are responsible for changing the departure angle. The arrow itself was part of the support beam, which was fastened with cylindrical hinges to the installation itself. When transporting missiles attached fortifications with the help of special supports, which were also on the boom.


Maintenance Technique


The targeting cab "Crab-1" was responsible for automated fire control. She managed the C75 / 60 mobile missile systems, and can detect and track at least ten targets at a distance from 15 to 160 kilometers from the station. It took only 32 seconds to process the coordinates of the air targets and the release of information for missile guidance. At the same time, the calculation accuracy index is 90%.


"Crab-1" refers to the composition of the complex and its modifications, incl. and the “Circle-M1” air defense system, but as a result of a reduction in the unit’s fire ability by 60 percent, this target designation cab was replaced with another model, the Polyana D-1. This replacement was made in 1981.


A new combat unit was characterized by the ability to support simultaneous 62 targets and could simultaneously process up to 16 targets. The system of coordination of units in the automatic mode was first implemented in this machine. Due to this, the number of destroyed airborne objects increased by 20%, and the ammunition consumption was reduced almost five times.

Photo 9


Technical specifications


After analyzing the performance of all the machines belonging to the complex, we can conclude about the combat effectiveness of the Krug air defense system:


  • Maximum speed - 50 km.
  • The power reserve of the complex (without refueling) - 300 km.
  • Response time is less than one minute.
  • Deploying SAMs - less than 5 minutes.
  • The range of the aerial target is from 11 to 43 km, with a height of 3-23,5 km.
  • The speed of flight of the targeted objects is no more than 800 m / s.

But accurate data on the combat effectiveness of the Krug complex are impossible. The combat use of technology has not been declassified until today. The only thing known is that these air defense systems were used during the war in Vietnam and during the improvement of the “Barlev air line” in Egypt.



Krug-A 2K11A


After the entry of this complex into service, work began on its improvement. The experience of fighting in Vietnam showed the need to reduce the dead zone. The Krug-A complex 2K11А entered service in 1967 year. The height of the damage line was reduced from 3 kilometers to 250 meters, and in range 11 kilometers to 9 kilometers.


Krug-M 2K11M


As a result, the subsequent improvement of the Krug-M missiles 2K11М entered service. The target hit height was increased from 23,5 to 24,5 km, and the range from 45 to 50 km.


Krug-M1 2K11M1


The Krug-M1 complex entered service in 1974 year. Compared to previous versions, the lower bound of the lesion decreased from 250 to 150 meters, and the near limit to 6-7 kilometers. In addition, there was the possibility of hitting the air target "in pursuit" at a distance of 20 kilometers.


In 2015, the anniversary model “50 years of the Krug” air defense system was released, which testifies to the relevance of the complex even after half a century and the high merit of its creators in front of his country. Currently all models are in storage.

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