Soviet generals and marshals who managed to survive the initial period of the war forever remembered how defenseless our troops were before dominating the German sky aviation. In this regard, the Soviet Union spared no resources for the creation of object and military air defense systems. In this regard, it so happened that our country occupies a leading position in the world in the number of types adopted for service and the number of built copies of ground anti-aircraft missile systems.
Reasons and features for the creation of a medium-range military air defense system
In the USSR, unlike other countries, different types of air defense systems were launched in parallel, having similar characteristics in the affected area and reach in height, intended for use in the country's air defense forces and in army air defense units. For example, until the mid-1990s, low-altitude air defense systems of the S-125 family were operated in the USSR Air Defense Forces, with a firing range of up to 25 km and a ceiling of 18 km. Mass deliveries of S-125 air defense systems to the troops began in the second half of the 1960s. In 1967, the Air Defense Forces of the Land Forces entered the Kub SAM, which had practically the same destruction range and could fight air targets flying at an altitude of up to 8 km. With similar capabilities in terms of combating an air opponent, the S-125 and the Cube had different operational characteristics: deployment and folding time, transportation speed, off-road movement capabilities, the principle of anti-aircraft missile guidance and the ability to carry out long combat duty.
The same can be said about the medium-range military mobile complex "Circle", which in the air defense system in terms of firing range corresponded to the S-75 air defense system. But, unlike the well-known “seventy-five”, exported and participating in many regional conflicts, the Krug air defense system, as they say, remained in the shadows. Many readers, even those interested in military equipment, are very poorly informed about the characteristics and stories Circle services.
Some Soviet high-ranking military leaders from the very beginning objected to the development of another medium-range air defense system, which could become a competitor to the S-75. So, the commander of the USSR Air Defense Marshal V.A. Sudets in 1963, while showing new equipment to the leadership of the country, proposed N.S. Khrushchev to curtail the Krug air defense program, promising to provide cover for ground forces with S-75 complexes. Since the unsuitability of the “seventy-five” for maneuvering war was understandable to a layman as well, the impulsive Nikita Sergeevich responded with a counter-proposal to the marshal - to put the S-75 to himself deeper.
In fairness, it should be said that in the late 1950s and early 1960s, a number of anti-aircraft artillery regiments of the ground forces were rearmament at the SA-75 air defense system (with a guidance station operating in the 10-cm frequency range). At the same time, anti-aircraft artillery regiments were renamed anti-aircraft missile (SRP). However, the use of the semi-stationary complexes SA-75 in the air defense of the SV was a strictly necessary measure, and the land investigators themselves considered such a solution to be temporary. To ensure air defense at the army and front levels, a medium-range mobile anti-aircraft missile system was required with high mobility (hence the requirement to deploy the main elements on a tracked base), short deployment and coagulation time, and the ability to conduct independent combat operations in the front line.
The first work on the creation of a medium-range military complex on a mobile chassis began in 1956. By mid-1958, technical assignments had been issued, and on the basis of the draft tactical and technical requirements, a resolution was adopted by the USSR Council of Ministers on the implementation of the Krug development and development project. On November 26, 1964, a decree of SM No. 966-377 was signed on the acceptance of the 2K11 air defense system into service. The decision also fixed its main characteristics: single-channel for the target (although it would be more correct for the division to write that it is three-channel for both the target and the missile channel); radio command guidance system for missiles using the "three points" and "half straightening" methods. Damage zone: 3-23,5 km in height, 11-45 km in range, up to 18 km in the course parameter of targets. The maximum speed of fired typical targets (F-4C and F-105D) is up to 800 m / s. The average probability of hitting a non-maneuvering target over the entire affected area is not lower than 0,7. The deployment time (coagulation) SAM - up to 5 minutes. To this we can add that the probability of defeat turned out to be less than that required by the TTZ, and the deployment time of 5 minutes was far from being carried out for all means of the complex.
The self-propelled launchers of the Krug air defense system were first publicly demonstrated during the military parade on November 7, 1966 and immediately attracted the attention of foreign military experts.
The composition of the air defense system "Circle"
The actions of the missile division (ZRN) were led by a control platoon, consisting of: target detection stations - SOTs 1C12, target designation reception booths - KPTs K-1 "Krab" (since 1981 - the combat control point from the Polyana-D1 ACS). In the air defense system there were 3 anti-aircraft missile batteries as part of the missile guidance station - SNR 1C32 and three self-propelled launchers - SPU 2P24 with two SAMs on each. Repair, maintenance of fixed assets of the division and replenishment of the ammunition were assigned to the personnel of the technical battery, which had at their disposal: control and test stations - KIPS 2V9, transport vehicles - TM 2T5, transport and loading machines - TZM 2T6, tankers for transporting fuel, technological equipment for assembling and refueling missiles.
All combat assets of the complex, except for TZM, were placed on tracked self-propelled lightly armored high-cross-country chassis and were protected from weapons mass destruction. The fuel reserve of the complex ensured the march at a speed of up to 45-50 km / h for removal of up to 300 km of course and the ability to conduct combat work on the spot for 2 hours. Three anti-aircraft missiles were part of the anti-aircraft missile brigade (air defense missile system), the full composition of which, depending on the location, could be different. The number of main combat assets (SOC, CHP and SPU) was always the same, but the composition of auxiliary units could vary. In teams equipped with various modifications of air defense systems, communication companies differed in types of medium-sized radio stations. An even more important difference was that in some cases one technical battery accounted for the entire zrb.
The following air defense systems are known: 2K11 Krug-Krug (produced since 1965), 2K11A Krug-A (1967), 2K11M Krug-M (1971) and 2K11M1 Krug-M1 (1974).
Radio-technical means of the Krug Circle
The eyes of the complex were: 1C12 target detection station and PRV-9B “Tilt-2” radio altimeter (P-40 “Bronya” radar). SOTS 1C12 was a radar circular view of the centimeter wave range. It provided for the detection of air targets, their identification and the issuance of target designation to missile guidance stations 1C32. All 1C12 radar equipment was located on the self-propelled tracked chassis of the AT-T heavy artillery tractor (“Object 426”). The mass of SOTS 1C12 prepared for work was about 36 tons. The average technical speed of the station was 20 km / h. The maximum speed on highways is up to 35 km / h. Cruising on dry roads, taking into account the operation of the station for 8 hours with full fueling of at least 200 km. Station deployment / folding time - 5 min. Calculation - 6 people.
1C12 Target Detection Station
The station equipment made it possible to analyze the characteristics of the movement of targets by crudely determining their course and speed using an indicator with long-term memorization of at least 100 seconds of marks from targets. Detection was made of a fighter aircraft at a distance of 70 km - at a target altitude of 500 m, 150 km - at an altitude of 6 km and 180 km - at an altitude of 12 km. In station 1C12 there was a topographic reference equipment, with the help of which a conclusion to a given area without using landmarks, station orientation, and accounting for parallax errors when transmitting data to 1C32 products was carried out. In the late 1960s, a modernized version of the radar appeared. Tests of the upgraded sample showed that the detection ranges of the station increased at the above heights to 85, 220 and 230 km, respectively. The station received protection from the Shrike-type PRR, and its reliability increased.
To accurately determine the range and altitude of flight of air targets in the control company, the use of the PRV-9B radio altimeter ("Tilt-2B", 1RL 19), which was towed by a KrAZ-214 car, was initially envisaged. PRV-9B, operating in the centimeter range, provided detection of a fighter aircraft at ranges of 115-160 km and at altitudes of 1-12 km, respectively.
Radio Altitude PRV-9
PRV-9B had a common power source (gas-turbine range finder power supply unit) with a 1C12 radar. In general, the PRV-9B radio altimeter was in full compliance with the requirements and was quite reliable. However, it was significantly inferior to the 1C12 rangefinder in terms of patency over soft soils and had a deployment time of 45 minutes.
Radio Altitude PRV-16
Subsequently, in brigades armed with later modifications of the Krug air defense system, the PRV-9B radio altimeters were replaced by the PRV-16B (Reliability-B, 1RL132B). The equipment and mechanisms of the PRV-16B altimeter are located in the K-375B body on the KrAZ-255B car. The PRV-16B altimeter does not have a power station; power is supplied from a rangefinder power source. The noise immunity and operational characteristics of PRV-16B have been improved compared to PRV-9B. The deployment time of PRV-16B is 15 minutes. A fighter target flying at an altitude of 100 m can be detected at a distance of 35 km, at an altitude of 500 m - 75 km, at an altitude of 1000 m - 110 km, at an altitude of more than 3000 - 170 km.
It is worth saying that radio altimeters were actually a pleasant option, greatly facilitating the process of issuing target designation CHP 1C32. It should be noted that for the transportation of PRV-9B and PRV-16B, a wheeled chassis was used, which was significantly inferior in patency to other elements of the complex on a caterpillar base, and the deployment and folding time of radio altimeters was several times longer than that of the main elements of the Krug Circle air defense system. In this regard, the main burden of detecting, identifying targets and issuing target designation in the division rested with SOC 1C12. Some sources mention that the radio altimeters were originally planned to be included in the platoon of the control unit, but, apparently, they were available only in the company management brigade.
Automated control systems
In the literature describing Soviet and Russian air defense systems, automated control systems (ACS) are either not mentioned at all, or are considered very superficially. Talking about the anti-aircraft complex "Circle", it would be wrong not to consider the ACS used in its composition.
ACS 9S44, aka K-1 "Crab", was created in the late 1950s and was originally intended for automated fire control of anti-aircraft artillery regiments armed with 57-mm S-60 assault rifles. Subsequently, this system was used at the regimental and brigade level to guide the actions of a number of first-generation Soviet air defense systems. The K-1 structure included a 9C416 combat control cabin (KBU on the Ural-375 chassis) with two AB-16 power supply units, 9С417 target designation booths (KPTs on the ZiL-157 or ZiL-131 chassis) divisions, a radar information transmission line "Grid-2K", GAZ-69T top loader, 9S441 spare parts and power equipment.
The system’s information display tools made it possible to visually demonstrate the air situation on the brigade’s commander’s console based on information from the P-40 or P-12/18 and P-15/19 radars that were available in the brigade’s radar company. When finding targets at a distance of 15 to 160 km, up to 10 targets were simultaneously processed, target designations with a forced turn of the antenna of the missile guidance station in given directions were issued, and acceptance of these target designations was checked. The coordinates of 10 targets selected by the brigade commander were transmitted directly to missile guidance stations. In addition, it was possible to receive brigades at the command post and relay information on two targets coming from the army air defense command post (front).
From the detection of an enemy aircraft to the issuance of target designation for the division, taking into account the distribution of targets and the possible need for transferring fire, an average of 30-35 seconds passed. The reliability of target designation reached more than 90% with an average time of searching for a target by a missile guidance station of 15–45 s. The calculation of the KBU was 8 people, not counting the chief of staff, the calculation of the KPC is 3 people. The deployment time was 18 minutes for the KBU and 9 for the KPTs, coagulation - 5 minutes 30 seconds and 5 minutes, respectively.
Already in the mid-1970s, the K-1 ACS “Crab” was considered primitive and outdated. The number of processed and followed targets at the "Crab" was clearly insufficient, and there was virtually no automated communication with higher management bodies. The main drawback of the ACS was that the commander through it could not inform the brigade commander and other divisors of their own chosen goals, which could lead to the shelling of one target by several anti-aircraft missiles. The division commander could inform the decision to carry out independent shelling of the target by radio station or by telephone, unless of course they managed to extend the field cable. Meanwhile, the use of the radio station in voice mode immediately deprived the ACS of an important quality - stealth. At the same time, it was very difficult, if at all possible, for the enemy’s radio reconnaissance to reveal the ownership of the telecode radio networks.
Due to the shortcomings of the ACS 9S44 in 1975, the development of a more advanced ACS 9S468M1 Polyana-D1 was started and in 1981 the latter was put into service. The combat control point of the brigade (PBU-B) 9C478 included the combat control cabin 9C486, the interface cabin 9C487 and two diesel power plants. The combat control center of the division (PBU-D) 9C479 consisted of a combat control cabin 9C489 and a diesel power station. In addition, the automated control system included a 9C488 maintenance cabin. All cabs and power plants PBU-B and PBU-D were located on the chassis of Ural-375 vehicles with a unified K1-375 van body. The exception was the UAZ-452T-2 top loader as part of the PBU-B. Topographic location PBU-D was provided by the appropriate means of the division. The communication between the front air defense (army) CP and the PBUB, between the PBU-B and the PBU-D, was carried out via telecode and radiotelephone channels.
The publication format does not allow to describe in detail the characteristics and operating modes of the Polyana-D1 system. But it can be noted that in comparison with the “Crab” equipment, the number of simultaneously processed targets at the brigade control point increased from 10 to 62, simultaneously controlled target channels - from 8 to 16. The corresponding indicators increased at the control point division from 1 to 16 and from 1 to 4 respectively. For the first time in Polyana-D1 automated control system, the tasks of coordinating the actions of subordinate units according to their own goals, issuing information about targets from subordinate units, identifying goals and preparing the commander’s decision were automated. Estimated effectiveness estimates have shown that the implementation of the Polyana-D1 automated control system increases the mathematical expectation of targets destroyed by the brigade by 21%, and the average missile consumption decreases by 19%.
Unfortunately, in the public domain there is no complete information on how many teams managed to master the new ACS. According to fragmentary information published on the air defense forums, it was possible to establish that the 133rd air defense brigade (Uterbog, GSVG) received the Polyana-D1 in 1983, the 202nd air defense brigade (Magdeburg, GSVG) - until 1986 and 180th air defense missile system (Anastasevka settlement, Khabarovsk Territory, Far Eastern Federal District) - until 1987. There is a high probability that many brigades armed with the Krug air defense system used the ancient “Crab” to disband or rearm the next generation systems.
1C32 missile guidance station
The most important element in the composition of the Krug missile launcher was the 1C32 missile guidance station. SNR 1C32 was intended to search for a target according to the control center of the SOC, its further auto-tracking along angular coordinates, issuing guidance data to SPU 2P24 and radio command control of an anti-aircraft missile in flight after its launch. SNR was located on a caterpillar self-propelled chassis, created on the basis of the self-propelled artillery mount SU-100P, and was unified with the chassis of the launcher of the complex. With a mass of 28,5 tons, a 400 hp diesel engine It ensured the movement of CHR along the highway with a maximum speed of 65 km / h. Cruising range - up to 400 km. Crew - 5 people.
1C32 missile guidance station
There is an opinion that CHP 1C32 was a "sore spot", in general, a very good complex. First of all, because the production of air defense systems was limited by the capabilities of the plant in Yoshkar-Ola, which handed over no more than 2 CHP per month. In addition, it is widely known that SNR is decrypted as a continuous repair station. Of course, reliability improved during the production process, and there were no particular complaints about the latest 1C32M2 modification. In addition, it was the SNR that determined the deployment time of the division — if 5 minutes were enough for SOC and SPU, then it took up to 15 minutes for the SSR. About 10 minutes more were occupied by warming up the lamp blocks and monitoring the functioning and tuning of the equipment.
The station was equipped with an electronic auto-range finder and operated according to the method of hidden monoconic scanning by angular coordinates. The capture of targets occurred at a distance of up to 105 km in the absence of interference, impulse power of 750 kW, and a beam width of 1 °. With interference and other negative factors, the range could be reduced to 70 km. To combat anti-radar missiles 1C32 had an intermittent mode of operation.
1C32 missile guidance station in the stowed position
An antenna post was located on the back of the hull, on which a coherent-pulse radar was installed. The antenna post had the possibility of circular rotation around its axis. Above the antenna of the narrow beam of the rocket channel, the antenna of the wide beam of the rocket channel was attached. Above the antennas of the narrow and wide missile channels, there was an antenna for transmitting instructions of the 3M8 SAM; On later modifications of the SIS, a television optical sight camera (TOV) was installed in the upper part of the radar.
Upon receipt of information from the SOC 1C32 on 1C12, the missile guidance station began processing the information and searched for targets in a vertical plane in automatic mode. At the moment of detecting the target, its tracking along the range and angular coordinates began. According to the current coordinates of the target, the calculating and resolving device worked out the necessary data to launch the SAM. Then, through the communication line, commands were sent to the 2P24 launcher to turn the launcher into the launch zone. After the 2P24 launcher was deployed in the right direction, the missile launcher was launched and the capture was conducted for escort. Through the antenna of the transmitter of the commands, the missile was controlled and undermined. Control commands and a one-time command for cocking a radio fuse came on board the rocket through the antenna of the command transmitter. Interference immunity SNR 1C32 was provided due to the separation of the working frequencies of the channels, the high energy potential of the transmitter and coding of control signals, as well as the work on two carrier frequencies for transmitting commands simultaneously. The fuse was fired with a miss less than 50 meters.
It is believed that the search capabilities of the 1C32 guidance station were insufficient for self-detection of targets. Of course, everything is relative. Of course, they were much higher at SOC. CHP scanned the space in the sector 1 ° in azimuth and +/- 9 ° in elevation. The mechanical rotation of the antenna system was possible in a sector of 340 degrees (the cables connecting the antenna unit with the housing prevented circular rotation) at a speed of about 6 rpm. Typically, the search engine conducted a search in a fairly narrow sector (according to some reports, about 10-20 °), especially since even with the presence of a control center an additional search was required from the SOC. Many sources write that the average time to search for a target was 15-45 seconds.
The self-propelled gun had a reservation of 14-17 mm, which was supposed to protect the crew from fragments. But with a close explosion of a bomb or warhead of an anti-radar missile (PRR), the antenna post was inevitably damaged.
It was possible to reduce the likelihood of damage to the PRR through the use of a television optical sight. According to declassified TOV test reports on SNR-125, it had two field of view angles: 2 ° and 6 °. The first - when using a lens with a focal length F = 500 mm, the second - with a focal length F = 150 mm.
When using a radar channel for preliminary target designation, the detection range of targets at altitudes of 0,2-5 km was:
- Mig-17 aircraft: 10-26 km;
- Mig-19 aircraft: 9-32 km;
- Mig-21 aircraft: 10-27 km;
- Tu-16 aircraft: 44-70 km (70 km at H = 10 km).
With a flight altitude of 0,2-5 km, the range of target detection was practically independent of altitude. At an altitude of more than 5 km, the range increases by 20-40%.
These data were obtained for a lens F = 500 mm, when using a 150 mm lens, the detection ranges are reduced by 17% for Mig-50 type targets, and by 16% for Tu-30 type targets. In addition to greater range, a narrow angle of view provided approximately twice as high accuracy. Wide, it corresponded to similar accuracy when using manual tracking of the radar channel. However, the 150 mm lens did not require high accuracy of target designation and worked better for low-altitude and group targets.
On SNR there was the possibility of both manual and automatic target tracking. There was also a PA mode - semi-automatic tracking, when the operator periodically drove the target with the handwheels into the "gate". At the same time, TV tracking was easier and more convenient than radar. Of course, the effectiveness of using TOV directly depended on the transparency of the atmosphere and time of day. In addition, when shooting with television accompaniment, it was necessary to take into account the location of the launcher relative to the SSR and the position of the Sun (in the sector +/- 16 ° in the direction of the sun, shooting was impossible).
Self-propelled launcher and transport and loading machine SAM "Circle"
SPU 10P60 was intended to deploy two combat-ready anti-aircraft missiles, transport and launch them at the command of the SNR at an angle from 2 to 24 ° to the horizon. Chassis launcher ("Product 123") based on the chassis SAU SU-100P unified with SNR 1C32. With a mass of 28,5 tons, a 400 hp diesel engine provided highway traffic at a maximum speed of 65 km / h. Cruising range PU on the highway was 400 km. Calculation - 3 people.
2P24 self-propelled launcher in combat position
The artillery part of SPU 2P24 is made in the form of a support beam with an arrow pivotally mounted in its rear part, lifted by two hydraulic cylinders and side brackets with supports for accommodating two missiles. When the rocket starts, the front support clears the way for the passage of the lower rocket stabilizer. On the march, the rockets were held by additional supports mounted on the arrow.
According to the combat charter, SPU at the firing position were to be placed at a distance of 150-400 meters from the SNR along an arc of a circle, in a line or at the corners of a triangle. But sometimes, depending on the terrain, the distance did not exceed 40-50 meters. The main concern of the calculation was that there were no walls, large stones, trees, etc., behind the launcher.
Transport and loading machine 2T6
With good training, a team of 5 people (3 people — SPU calculation and 2 people — TZM) loaded one rocket with an entrance from 20 meters in 3 minutes 40-50 seconds. If necessary, for example, if the rocket failed, it could be loaded back onto the TZM, and loading itself in this case took even less time.
The use of the Ural-375 wheeled chassis for a transport-loading machine was not generally critical. If necessary, 2P24 caterpillar self-propelled guns could tow TZM when driving on soft soils.
3M8 anti-aircraft guided missile
It is known that in the USSR until the beginning of the 1970s there were serious problems with the possibility of creating effective solid rocket fuel recipes, and the choice of a ramjet for an anti-aircraft missile during the design of the Krug air defense system was predetermined from the very beginning. A medium-range solid-propellant missile system created in the late 1950s would be too cumbersome, and the developers refused to use liquid-propellant rocket engines on the basis of safety requirements and operational reliability.
PRVD had high efficiency and simple design. Moreover, it was much cheaper than a turbojet engine and atmospheric oxygen was used to burn fuel (kerosene). The specific thrust of the air propulsion system was superior to other types of engines and at a rocket flight speed 3-5 times higher than the sonic one, it was characterized by the lowest fuel consumption per thrust unit even in comparison with a turbojet engine. The disadvantage of ramjet engines was insufficient thrust at subsonic speeds due to the lack of the necessary high-pressure head at the inlet of the air intake, which led to the need to use launch boosters that accelerated the rocket to a speed of 1,5-2 times the speed of sound. However, the accelerators had almost all anti-aircraft missiles created at that time. There were at the front-end engine and disadvantages peculiar only to this type of engine. Firstly, the complexity of the development - each ramjet is unique and requires lengthy refinement and testing. This was one of the reasons that postponed the adoption of the “Circle” by almost 3 years. Secondly, the rocket had a large frontal resistance, and quickly lost speed in the passive section. Therefore, it was impossible to increase the range of shelling of subsonic targets due to inertia flight, as was done on the S-75. Finally, the ramjet unstable worked at large angles of attack, which limited the maneuverability of the SAM.
The first modification of the 3M8 anti-aircraft missile appeared in 1964. It was followed by: 3M8M1 (1967), 3M8M2 (1971) and 3M8M3 (1974). There were no fundamental differences between them, basically the height of the target’s defeat decreased, the minimum range and maneuverability increased.
A high explosive fragmentation warhead 3N11 / 3N11M weighing 150 kg was located directly behind the fairing of the central body of the main engine air intake. The weight of the explosive - a mixture of RDX and TNT was 90 kg, a notch on a steel shirt formed 15000 finished fragments of 4 grams each. Judging by the recollections of veterans - Krugovtsev, there was also a variant of a missile with a "special" warhead, similar to the V-760 (15D) S-75 missile. The missile was equipped with a non-contact radio fuse, a command receiver and an on-board impulse transponder.
The layout of the missile 3M8
The rotary wings (2206 mm span) on the SAM shell were placed according to the X-shaped pattern and could deviate in the range of 28 °, the stationary stabilizers (2702 mm span) - according to the cross-shaped pattern. The length of the rocket is 8436 mm, the diameter is 850 mm, the starting weight is 2455 kg. 270 kg of kerosene and 27 kg of isopropyl nitrate were refueled in the internal fuel tanks. On the marching section, the rocket accelerated to 1000 m / s.
In different sources, conflicting data is published on the maximum possible overload of an anti-aircraft missile, but even at the design stage, the maximum overload of a missile was set at 8g.
Another obscure point - all sources say that the fuse is triggered by a miss up to 50 meters, otherwise there is a team to self-destruct. But there is information that the warhead was directed, and when detonated, it formed a cone of fragments up to 300 meters long. There is also a mention that in addition to the K9 command for cocking the radio fuse, there was also the K6 team, which establishes the dispersion form of the warhead fragments and this form depended on the speed of the target.
As for the minimum height of the targets being hit, it should be remembered that it is determined both by the capabilities of the fuse of the warhead and the control system of the SAM. For example, with radar tracking of a target, restrictions on the height of the target are greater than with television, which, incidentally, was characteristic of all radar equipment of that time.
Former operators repeatedly wrote that they were able to shoot down targets at 70-100 meters at control and training firing. Moreover, in the early to mid-1980s, attempts were made to use the Krug air defense systems of later versions to practice the destruction of low-flying cruise missiles. However, to combat low-altitude targets anti-aircraft missiles with anti-aircraft guns had insufficient maneuverability, and the likelihood of intercepting missiles was small. On the basis of 3M8 missiles, a universal missile was developed to combat not only aircraft, but also ballistic missiles at ranges up to 150 km. Universal missiles had a new guidance system and warhead directional action. But in connection with the beginning of the development of the S-300V complex, work in this direction was curtailed.
Comparison of the Krug air defense system with foreign and domestic systems
Briefly consider anti-aircraft missiles with ramjet engines created abroad. As you know, the United States and its closest NATO allies during the Cold War did not have medium-range mobile air defense systems. The task of covering the troops from air strikes in Western countries was mainly assigned to fighters, and towed anti-aircraft missile systems were considered as an auxiliary means of air defense. In the 1950-1980s, in addition to the United States, work to create their own air defense systems was carried out in the UK, France, Italy and Norway. Despite the advantages of SAM with ramjet, from the above countries, except the USA and Great Britain, anti-aircraft missiles with such an engine were brought to mass production, but all of them were intended for ship systems, or were placed in stationary positions.
About 5 years before the start of mass production of the Krug air defense system, the RIM-8 Talos air defense launchers appeared on the decks of heavy American cruisers.
RIM-8A anti-aircraft missile launcher on the deck of the USS Little Rock (CG-4) missile cruiser
At the initial and middle stages of the trajectory, the rocket flew in the radar beam (this guidance method is also known as the “saddled beam”), and at the final it switched to homing by the signal reflected from the target. SAM RIM-8A weighed 3180 kg, had a length of 9,8 m and a diameter of 71 cm. The maximum firing range was 120 km, reach in height - 27 km. Thus, a much heavier and larger American missile surpassed the Soviet SAM 3 M8 in range by more than two times. At the same time, the very significant dimensions and high cost of Talos air defense systems prevented its wide distribution. This complex was available on heavy cruisers of the Albany type, converted from Baltimore-type cruisers, on three Galveston-class cruisers, and on the Long Beach nuclear-powered missile cruiser. Due to the excessive weight and dimensions, the RIM-8 Talos launchers were removed from the decks of American cruisers in 1980.
In 1958, the UK adopted the Bloodhound Mk.I. The “Bloodhound” anti-aircraft missile had a very unusual layout; two direct-flow “Tor” air-propelled engines that operated on liquid fuel were used as a marching propulsion system. Marching engines were mounted in parallel on the upper and lower parts of the hull. To accelerate the rocket to the speed at which ramjets could operate, four solid fuel boosters were used. Accelerators and part of the plumage were reset after the rocket was accelerated and the marching engines began to operate. Direct-flow marching engines dispersed the rocket in the active section to a speed of 750 m / s. Finishing missiles went with great difficulties. This was mainly due to the unstable and unreliable operation of ramjet engines. Satisfactory results of the air traffic control were achieved only after about 500 fire tests of engines and missile launches, which were carried out at the Australian Woomera training ground.
Bloodhound anti-aircraft missiles on launchers
The missile was very large and heavy, in connection with which its placement on a mobile chassis was impossible. The length of the SAM was 7700 mm, diameter 546 mm, and the weight of the rocket exceeded 2050 kg. To aim at the target, a semi-active radar seeker was used. The firing range of the Bloodhound Mk.I air defense system was a little over 35 km, which is comparable to the range of the much more compact low-altitude American solid-fuel air defense system MIM-23B HAWK. Characteristics SAM Bloodhound Mk. II were significantly higher. Due to the increase in the amount of kerosene on board and the use of more powerful engines, the flight speed increased to 920 m / s, and range - up to 85 km. The upgraded rocket became longer by 760 mm, its starting weight increased by 250 kg.
SAM "Bloodhound", in addition to the UK, were in service in Australia, Singapore and Sweden. In Singapore, they were in service until 1990. In the British Isles, they covered large airbases until 1991. The Bloodhounds lasted the longest in Sweden - until 1999.
In the armament of the British destroyers in the years 1970-2000 there was a Sea Dart SAM. The official adoption of the complex into service was issued in 1973. The anti-aircraft missile of the Sea Dart complex had an original and rarely used scheme. Two stages were used in it - accelerating and marching. The booster engine was powered by solid fuel, its task is to give the rocket the speed necessary for the stable operation of the ramjet engine.
Sea Dart anti-aircraft missile on a ship launcher
The mid-flight engine was integrated into the rocket body; in the bow there was an air intake with a central body. The missile turned out to be quite “clean” in aerodynamic terms, it is made according to the normal aerodynamic design. The diameter of the rocket is 420 mm, the length is 4400 mm, the wingspan is 910 mm. Starting weight - 545 kg.
Comparing the Soviet 3M8 SAM and the British Sea Dart, it can be noted that the British missile was lighter and more compact, and also had a more advanced semi-active radar guidance system. The most advanced modification, Sea Dart Mod 2, appeared in the early 1990s. At this complex, the firing range was increased to 140 km and the ability to combat low-altitude targets was improved. Having rather good characteristics, the long-range Sea Dart SAM was not widely used and was used only on the British Type 82 and Type 42 destroyers (Sheffield type destroyers), as well as on Invincible aircraft carriers.
If desired, on the basis of the Sea Dart, it was possible to create a good mobile air defense system, with a very good firing range by the standards of the 1970-1980s. The design of the land complex known as the Guardian was carried out in the 1980s. In addition to the fight against aerodynamic targets, it was also planned to use it to intercept OTR. However, due to financial constraints, the creation of this SAM did not advance beyond the paper stage.
A comparison will be made of the 3M8 missile with the V-759 (5Y23) missile used in the S-75M2 / M3 air defense system. The masses of the rockets are approximately equal, the speeds too. Due to the use of the passive section, the firing range on subsonic targets at the B-759 is greater (up to 55 km). Due to the lack of information on the maneuverability of missiles, it is difficult to speak. We can assume that the 3M8 maneuverability at low altitudes left much to be desired, but it was no coincidence that the S-75 missiles were called "flying telegraph poles." At the same time, the Krug missiles were more compact, which facilitated their transportation, loading and position selection. But the most important thing is that the use of toxic fuels and an oxidizing agent not only made life extremely difficult for the personnel of the technical division, which had to equip missiles in gas masks and OZK, but also reduced the combat survivability of the complex as a whole. When a rocket was damaged on the ground during air raids (there were dozens of such cases in Vietnam), then these liquids, in contact, self-ignite, which inevitably led to a fire and explosion. In the event of a missile being blown up in the air until the fuel and oxidizer are completely exhausted, tens of liters of toxic fog settled to the ground.
In the next part, we will focus on the service and combat use of the Krug air defense system. The authors would be very grateful to readers who have experience in operating this complex, who are able to point out possible shortcomings and inaccuracies, possibly available in this publication.
To be continued ...