Tuesday 15 July 2008

SS 18 SATAN : Russian Intecontinental Ballistic Missille

The R-36 (Russian: Р-36) is a family of intercontinental ballistic missiles (ICBMs) and space launch vehicles designed by the Soviet Union during the Cold War. The original R-36 was produced under the Soviet industry designation 8K67 and was given the NATO reporting name SS-9 Scarp. The modern version, the R-36M was produced under the GRAU designations 15A14 and 15A18 and was given the NATO reporting name SS-18 Satan; this missile gave the Soviet Union first strike advantage over the USA, particularly because of its very heavy throw weight. It was believed that only a limited amount of US ICBM silos would survive a successful first strike by missiles like the SS-18 Satan.

Description

The R-36 (SS-9) is a two-stage rocket powered by a liquid bipropellant, with UDMH as fuel and nitrogen tetroxide as an oxidizer. It carries one of three different warheads developed especially for this missile:

An additional warhead, the Mod 3, was proposed (it was to be a FOBS, a missile that travels through space in a low-earth orbit), but was not adopted due to the Outer Space Treaty. The R-36P missile was developed to carry the Mod 4 warhead, while the R-36O (the letter O) was to be for the Mod 3 FOBS. R-36 and R-36P missiles were hot launched from their silos.

The R-36M (SS-18) is similar to the R-36 in design, but has the capacity to mount a single warhead of up to 20mt (megatons) of TNT in yield, or a MIRV payload of up to 10 warheads, each with a 550-750 kt (kiloton) yield. Throw-weight of the missile is 8,800 kg. This makes the Soviet R-36 the world's heaviest ICBM; for comparison, the heaviest US MIRV-ed ICBM (the LGM-118 Peacekeeper) carried 10 warheads of 300 kT each, but its throw-weight was less than half that of the R-36M, at 4000 kg. The R-36M has two stages. The first is a 460,000 kgf (4.5 MN) thrust motor with four combustion chambers and nozzles. The second stage is a single-chamber 77,000 kgf (755 kN) thrust motor.

All R-36 variants were designed to be launched from silos in dispersed and hardened locations. The R-36M is placed into its 39 m deep silo in a tubular storage/launch container. Upon launch the missile is shot out of the tube, mortar-fashion, by a piston, driven by the expansion of gases from a slow-burning black powder charge inside the piston. The missile's main engine is ignited tens of metres above the ground, preventing any damage to the internal equipment of the silo itself from the rocket engine's fiery efflux. This “cold start” enables quick removal of the empty launch tube from the silo, reloading a second missile in its container, and thus a second launch before the anticipated retaliatory strike arrives. Thanks to this second salvo capability, the system can launch twice the number of own missiles before the opposing counter-silo warheads can arrive at the launch site of the R-36M.[citation needed]

Development

Development of the R-36 was begun by OKB-586 (Yuzhnoye) in Dnepropetrovsk, Ukraine) in 1962, and built upon the work of the R-16 program. The Chief Designer was Mikhail Yangel. Initial development was of light, heavy, and orbital versions, with flight testing from 1962 through 1966, at which time initial operational capability was achieved. News of the development of the orbital version caused alarm in the West with the possibility that the Soviets would be able to launch large number of nuclear weapons into orbit where there was no capability to intercept them. The prospect of orbital nuclear weapons led both sides to agree a treaty banning the use of weapons of mass destruction in space.

In 1970, development of a fourth version, capable of delivering multiple warheads, was developed, and test flown the next year.

Further improvement of the R-36 led to the design of the R-36M, which provided a theoretical first-strike capability -- the ability to destroy the United States's LGM-30 Minuteman ICBM silos and launch control centers before they could retaliate. However, neither the Soviet Union nor the Russia Federation have ever publicly delineated the missile's particular role in their arsenal. The initial design of the R-36M called for a single massive 12-Mt warhead to be delivered over a range of 10,600 km. The missile was first tested in 1973 but this test ended in failure. After several delays the R-36M was deployed in December of 1975. This “Mod-1” design was delivered with a single 18–20 Mt warhead and a range of just over 11,000 km. This new version was given a new identity by NATO: SS-18 Satan.

The SS-18 has gone through six separate modifications, with the first modification (Mod-1) being phased out by 1984. The final modification (Mod-6) designated R-36M-2 “Voevoda” was deployed in August of 1988. This missile could deliver the same 18–20-Mt warhead 16,000 km. Modifications prior to Mod-6 mainly introduced MIRV (Multiple independent reentry vehicles) warheads. These missiles (Mods-2, 4, and 5) surpassed their western counterpart the US LG-118A Peacekeeper in terms of megatons delivered, range, and survivability, but were inferior in terms of accuracy (CEP).

Multiple warheads

Missiles of the R-36M/SS-18 family have never been deployed with more than ten warheads. But given their large throw-weight (8.8 tonnes as specified in START), they have the capacity to carry considerably more than that. Among the projects that the Soviet Union considered in the mid-1970s was that of a 15A17 missile—a follow-on to the R-36MUTTH (15A18).[1] The missile would have had an even greater throw-weight—9.5 tonnes—and would be able to carry a very large number of warheads. Five different versions of the missile were considered. Three of these versions would carry regular warheads – 38x 250 kt yield, 24x 500 kt yield, or 15-17x 1 Mt yield. Two modifications were supposed to carry guided warheads (“upravlyaemaya golovnaya chast”) – 28x 250 kt or 19x 500 kt.[2] However, none of these upgraded models were ever developed. The SALT II Treaty, signed in 1979, prohibited increasing the number of warheads ICBMs could carry. Equally, from a strategic point of view, concentrating so many warheads on silo-based missiles was not seen as desirable, since it would have made a large proportion of the USSR's warheads vulnerable to a counterforce strike.

The operational deployment of the R36M/SS-18 consisted of the R-36MUTTH, which carried ten 500 kt warheads, and its follow-on, the R-36M2 (15A18M), which carried ten 800 kt warheads (Single-warhead versions with either 8.3 Mt or 20 Mt warhead also existed at some point). To partially circumvent the treaty, the missile, utilizing the capacity unused due to 10 warhead limitation, was equipped with 40 heavy decoys.[3] These decoys would appear as warheads to any defensive system, making each missile as hard to intercept as 50 single-warhead, rendering potential ABM systems ineffective.

Deployment

At full deployment, before the fall of the Soviet Union in 1991, 308 R-36M launch silos were operational. After the breakup of the USSR, 204 of these were located on the territory of the Russian Federation and 104 on the territory of newly independent Kazakhstan. In the next few years Russia reduced the number of R-36M launch silos to 154 to conform with the START I treaty. The missiles in Kazakhstan were all deactivated by 1995. The subsequent START II treaty was to eliminate all R-36M missiles but it did not enter into force and the missiles remained on duty.

R-36orb

The development of the R-36 missile complex for use with the 8К69 fractional-orbit missile ("FOBS") began on April 16th, 1962. Such a missile provides some advantages over a conventional ICBM. The range is limited only by the parameters of the orbit that the re-entry vehicle has been placed into, and the re-entry vehicle may come from either direction, compelling the enemy to build considerably more expensive anti-missile systems. Due to the possibility of placing the warhead in orbit and keeping it there for some time, it is possible to reduce the time required to strike to just a few minutes. It is also very much more difficult to predict where the warhead will land, since while the re-entry vehicle is on orbit, it is a very small object with few distinguishing marks and is hard to detect; moreover, since the warhead can be commanded to land anywhere along the orbit's ground track, even detecting the warhead on orbit does not allow accurate prediction of its intended target.

The structure and design of the fractional-orbit bombardment system were similar to a conventional P-36 ICBM system. A two-stage rocket was equipped by the liquid rocket engines using storable propellants. The silo launcher and command point were hardened against a nuclear explosion. The basic difference from a conventional ICBM consists of the design of the re-entry vehicle, which is fitted with a single 2.4Mt warhead, de-orbit engine and control block. The control system uses independent inertial navigation and radar-based altimeter which measures orbit parameters twice — in the beginning of an orbital path and just before de-orbiting engine firing.

Flight testing consisted of 15 successful launches and 4 failures. During test launch #17, warhead was retrieved with a parachute. Flight tests of a rocket have been completed by May 20th, 1968 and on November 19th of the same year it entered service. The first(and the only) regiment with 18 launchers was deployed on August 25th 1969.

R-36orb(8К69) were retired from service in January, 1983 as a part of SALT II treaty (they were considered "space-based" nuclear weapons).

Tsyklon series of civilian space launchers is based on the R-36orb(8K69) design.

Elimination

In the last decade Russian armed forces have been steadily reducing the number of R-36M missiles in service, withdrawing those that age past their designed operational lifetime. About 40 missiles of the most modern variant R-36M2 (or RS-20V) will remain in service until 2020 and will be then replaced by newer MIRV version of Topol-M. In March 2006 Russia made agreement with Ukraine that will regulate cooperation between the two countries on maintaining the R-36M2 missiles. It was reported that the cooperation with Ukraine will allow Russia to extend service life of the R-36M2 missiles by at least ten years to 25 year.[4]


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