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SAM S-75 Dvina. ЗРК С-75 “Двина”

Image by Peer.Gynt
Saint-Petersburg. Artillery Museum.

The S-75 Dvina (Russian: С-75; NATO reporting name SA-2 Guideline) is a Soviet-designed, high-altitude, command guided, surface-to-air missile (SAM). Since its first deployment in 1957 it has become the most widely-deployed air defense missile in history. It scored the first destruction of an enemy aircraft by a SAM, shooting down a Taiwanese Martin RB-57D Canberra over China, on October 7, 1959 by hitting it with three V-750 (1D) missiles at an altitude of 20 km (65,600 ft). The success was attributed to Chinese fighters at the time in order to keep the S-75 program secret.
This system first gained international fame when an S-75 battery, using the newer, longer-range and higher-altitude V-750VN (13D) missile shot down the U-2 of Francis Gary Powers overflying the Soviet Union on May 1, 1960.[3] The system was also deployed in Cuba during the Cuban Missile Crisis, where on October 27, 1962, it shot down the U-2 flown by Rudolf Anderson, almost precipitating nuclear war.[4] North Vietnamese forces used the S-75 extensively during the Vietnam War to defend Hanoi and Haiphong. It has also been locally produced in the People’s Republic of China using the names HQ-1 and HQ-2. Other nations have produced so many local variants combining portions of the S-75 system with both indigenously-developed components or third-party systems that it has become virtually impossible to find a pure S-75 system today,
Development
In the early 1950s, the United States Air Force rapidly accelerated its development of long-range jet bombers carrying nuclear weapons. The USAF program led to the deployment of Boeing B-47 Stratojet supported by aerial refueling aircraft to extend its range deep into the Soviet Union. The USAF quickly followed the B-47 with the development of the Boeing B-52 Stratofortress, which had greater range and payload than the B-47. The range, speed, and payload of these U.S. bombers posed a significant threat to the Soviet Union in the event of a war between the two countries.
onsequently, the Soviets initiated the development of improved air defense systems. Although the Soviet Air Defence Forces had large numbers of anti-aircraft artillery (AAA), including radar-directed batteries, the limitations of guns versus high-altitude jet bombers was obvious. Therefore, the Soviet Air Defense Forces began the development of missile systems to replace the World War II-vintage gun defenses.
In 1953, KB-2 began the development of what became the S-75 under the direction of Pyotr Grushin. This program focused on producing a missile which could bring down a large, non-maneuvering, high-altitude aircraft. As such it did not need to be highly maneuverable, merely fast and able to resist aircraft counter-measures. For such a pioneering system, development proceeded rapidly, and testing began a few years later. In 1957, the wider public first became aware of the S-75 when the missile was shown at that year’s May Day parade in Moscow.
Initial deployment
Wide-scale deployment started in 1957, with various upgrades following over the next few years. The S-75 was never meant to replace the S-25 Berkut surface-to-air missile sites around Moscow, but it did replace high-altitude anti-aircraft guns, such as the 130 mm KS-30 and 100 mm KS-19. Between mid-1958 and 1964, U.S. intelligence assets located more than 600 S-75 sites in the USSR. These sites tended to cluster around population centers, industrial complexes, and government control centers. A ring of sites was also located around likely bomber routes into the Soviet heartland. By the mid-1960s, the Soviet Union had ended the deployment of the S-75 with perhaps 1,000 operational sites.
In addition to the Soviet Union, several S-75 batteries were deployed during the 1960s in East Germany to protect Soviet forces stationed in that country. Later the system was sold to most Warsaw Pact countries and was provided to China, North Korea, and eventually, North Vietnam.
Employment
While the shooting down of Francis Gary Powers’ U-2 in 1960 is the first publicized success for the S-75, the first aircraft actually shot down by the S-75 was a Taiwanese Martin RB-57D Canberra high-altitude reconnaissance aircraft. In this case, the aircraft was hit by a Chinese-operated S-75 site near Beijing on October 7, 1959. Over the next few years, the Taiwanese ROCAF would lose a number of aircraft to the S-75: both RB-57s and various drones. On May 1, 1960, Gary Powers’s U-2 was shot down while flying over the testing site near Sverdlovsk, although it is thought to have taken 14 missiles to hit his high-flying plane. That action led to the U-2 Crisis of 1960. Additionally, Chinese S-75s downed five ROCAF-piloted U-2s based in Taiwan.[5]
During the Cuban Missile Crisis, a U-2 piloted by USAF Major Rudolf Anderson was shot down over Cuba by an S-75 in October 1962.[6]
In 1965, North Vietnam asked for some assistance against American airpower, for their own air-defense system lacked the ability to shoot down aircraft flying at high altitude. After some discussion it was agreed to supply the PAVN with the S-75. The decision was not made lightly, because it greatly increased the chances that one would fall into US hands for study. Site preparation started early in the year, and the US detected the program almost immediately on April 5, 1965. While military planners pressed for the sites to be attacked before they could become operational, their political leaders refused, fearing that Soviet technical staff might be killed.
On July 24, 1965, a USAF F-4C aircraft was shot down by an SA-2.[7] Three days later, the US responded with Operation Iron Hand to attack the other sites before they could become operational. Most of the S-75 were deployed around the Hanoi-Haiphong area and were off-limits to attack (as were local airfields) for political reasons. President Lyndon Johnson announced on public TV that one of the other sites would be attacked the next week. The Vietnamese removed the missiles and replaced them with decoys, while moving every available anti-aircraft gun into the approach routes. The tactic worked, causing heavy American casualties.
The missile system was used widely throughout the world, especially in the Middle East, where Egypt and Syria used them to defend against the Israeli Air Force, with the air defense net accounting for the majority of the downed Israeli aircraft. The last apparent success seems to have occurred during the War in Abkhazia (1992–1993), when Georgian missiles shot down a Russian Sukhoi Su-27 fighter near Gudauta on March 19, 1993.
Countermeasures and counter-countermeasures
Between 1965 and 1966, the US delivered a number of solutions to the S-75 problem. The Navy soon had the Shrike missile in service and mounted their first offensive strike on a site in October 1965. The Air Force responded by fitting B-66 bombers with powerful jammers (that blinded the early warning radars) and by developing smaller jamming pods for fighters (that denied range information to the radars). Later developments included the Wild Weasel aircraft, which were fitted with anti-radiation air-to-surface missile systems made to home in on the radar from the threat. This freed them to shoot the sites with Shrikes of their own.
The Soviets and Vietnamese, however, were able to adapt to some of these tactics. The USSR upgraded the radar several times to improve ECM (electronic counter measure) resistance. They also introduced a passive guidance mode, whereby the missile could lock on the jammer itself. This had an added advantage, because the radar had to be turned off, which prevented Shrikes from being fired. Moreover, some new tactics were developed to combat the Shrike. One of them was to point the radar to the side and then turn it off briefly. Since the Shrike was a relatively primitive anti-radiation missile, it would follow the beam away from the radar and then simply crash when it lost the signal (after the radar was turned off). Another was a "false launch" in which the tracking radar was turned on, but the missiles were not actually fired. This allowed the missile crew to see if the target was equipped with a Shrike. If the aircraft fired one, the Shrike could be neutralized with the side-pointing technique without sacrificing any S-75s.
Despite these advances, the US was able to come up with effective ECM packages for the B-52E models. These planes were able to fly raids against Hanoi with relatively few losses (though still significant enough to cause some concern; see Operation Linebacker II).
Replacement systems
Soviet Air Defence Forces started to replace the S-75 with the vastly superior SA-10 and SA-12 systems in the 1980s. Today only a few hundred, if any, of the 4,600 missiles are still in Russian service, even though they underwent a modernization program as late as 1993.[citation needed]
The S-75 remains in widespread service throughout the world, with some level of operational ability in 35 countries. Vietnam and Egypt are tied for the largest deployments at 280 missiles each, while North Korea has 270, and Poland has 240. The Chinese also deploy the HQ-2, an upgrade of the S-75, in relatively large numbers.
Soviet doctrinal organization
The Soviet Union used a fairly standard organizational structure for S-75 units. Other countries that have employed the S-75 may have modified this structure. Typically, the S-75 is organized into a regimental structure with three subordinate battalions. The regimental headquarters will control the early-warning radars and coordinate battalion actions. The battalions will contain several batteries with their associated acquisition and targeting radars.
Site layout
Each battalion will typically have six, semi-fixed, single-rail launchers for their V-750 missiles positioned approximately 60 to 100 m (200 to 330 ft) apart from each other in a hexagonal "flower" pattern, with radars and guidance systems placed in the center. It was this unique "flower" shape that led to the sites being easily recognizable in reconnaissance photos. Typically another six missiles are stored on tractor-trailers near the center of the site.
An example of a site can be seen here just to the west of the junction to Bosra on the M5 motorway in Syria, south of Damascus. This location covers the borders with both Israel and Jordan, so it is of strategic importance.
Missile
V-750

V-750V 1D missile on a launcher
TypeSurface-to-air missile
Place of origin Soviet Union
Production history
VariantsV-750, V-750V, V-750VK, V-750VN, V-750M, V-750SM, V-750AK
Specifications (V-750[9])
Weight2,300 kg (5,100 lb)
Length10,600 mm (420 in)
Diameter700 mm (28 in)
WarheadFrag-HE
Warhead weight200 kg (440 lb)
Detonation
mechanismCommand
PropellantSolid-fuel booster and a storable liquid-fuel upper stage
Operational
range45 km (28 mi)
Flight altitude20,000 m (66,000 ft)
Boost time5 s boost, then 20 s sustain
SpeedMach 3.5
Guidance
systemRadio control guidance
Accuracy65 m
Launch
platformSingle rail, ground mounted (not mobile)
The V-750 is a two-stage missile consisting of a solid-fuel booster and a storable liquid-fuel upper stage, which burns red fuming nitric acid as the oxidizer and kerosene as the fuel. The booster fires for about 4–5 seconds and the main engine for about 22 seconds, by which time the missile is traveling at about Mach 3. The booster mounts four large, cropped-delta wing fins that have small control surfaces in their trailing edges to control roll. The upper stage has smaller cropped-deltas near the middle of the airframe, with a smaller set of control surfaces at the extreme rear and (in most models) much smaller fins on the nose.
The missiles are guided using radio control signals (sent on one of three channels) from the guidance computers at the site. The earlier S-75 models received their commands via two sets of four small antennas in front of the forward fins, while the D model and later models used four much larger strip antennas running between the forward and middle fins. The guidance system at an S-75 site can handle only one target at a time, but it can direct three missiles against it. Additional missiles could be fired against the same target after one or more missiles of the first salvo had completed their run, freeing the radio channel.
The missile typically mounts a 195 kg (430 lb) fragmentation warhead, with proximity, contact, and command fusing. The warhead has a lethal radius of about 65 m (213 ft) at lower altitudes, but at higher altitudes the thinner atmosphere allows for a wider radius of up to 250 m (820 ft). The missile itself is accurate to about 75 m (246 ft), which explains why two were typically fired in a salvo. One version, the SA-2E, mounted a 295 kg (650 lb) nuclear warhead of an estimated 15 Kiloton yield or a conventional warhead of similar weight.
Typical range for the missile is about 45 km (28 mi), with a maximum altitude around 20,000 m (66,000 ft). The radar and guidance system imposed a fairly long short-range cutoff of about 500 to 1,000 m (1,600 to 3,300 ft), making them fairly safe for engagements at low level.

en.wikipedia.org/wiki/S-75_Dvina

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