Minuteman II was longer and heavier than Minuteman I, with extended range (12,500 km compared to 10,000 km) and a more accurate warhead. It entered service in 1966, and by 1969 it had replaced all Minuteman Is. Of the 450 deployed, ten were subsequently reconfigured to carry the Emergency Rocket Communications System (ERCS) and thus no longer carried nuclear warheads.
fn3
Minuteman III introduced a third stage and was also the first US ICBM to carry MIRVs, but its basing and launch systems were the same as those of Minuteman II.
Peacekeeper (MX)
The Missile, Experimental (MX) programme was one of the longest and most controversial in the Cold War, with much of the argument centring on the question of basing. Indeed, MX consumed money at a prodigious rate and gave rise to an industry of its own for many years before it began to make any contribution to Western deterrence. The programme started in the early 1970s, and eventually resulted in the fielding of just fifty Peacekeeper missiles in 1986. After all the argument on different basing systems, these were placed in Minuteman III silos. Peacekeeper had a range of 9,600 km and carried ten W-87 warheads, each with a yield of 300 kT and an accuracy (CEP) of 100 m, giving them an extremely high lethality. During the Cold War these would almost inevitably have been targeted on both Soviet leadership bunkers and ‘superhardened’ ICBM silos.
SOVIET ICBM DEVELOPMENT
fn4
The first official rocket-propulsion laboratory in the Soviet Union was opened in 1921, but attention was concentrated on short-range artillery missiles until after the Second World War, when the USSR produced a copy of the German A-4, known under the NATO system as the SS-1, ‘Scud’.
fn5
The SS-2, ‘Sibling’, was similar, but with Soviet advances to increase range and reliability, while the SS-3, ‘Shyster’, was the first to carry an atomic warhead.
SS-6
In the 1950s the USSR found itself without a strategic bomber force to counter the B-36s, B-47s and B-52s of the USAF, and the quickest way to produce an answer was an ICBM. The technology of the time was, however, comparatively crude: warheads were heavy, and the sum total of the components, the payload and the fuel needed for intercontinental range came to well over 200 tonnes. Nevertheless, the USSR, which was never deterred by the size of a project, pressed ahead to produce the huge SS-6, ‘Sapwood’, which first flew on 3 August 1957. The necessary thrust was obtained by using a basic missile surrounded by four large strap-on boosters, the main missile and each booster having a 102,00 kgf thrust rocket motor. Thus, the device had a launch weight of no less than 300 tonnes, but was powered by motors with a total thrust of 510,000 kgf.
As a strategic weapon the SS-6 was less than successful: it had a poor reaction time, due to the need to load huge quantities of cryogenic fuel,
fn6
it was far too big to be put in a silo, its electronics were crude and unreliable, and it was very inaccurate, with a CEP of some 8 km. The knowledge that the USSR had such a powerful launch vehicle had a major psychological impact on the USA, but no more than four SS-6s were ever deployed operationally as ICBMs. The SS-6 was, however, used for space launches for many years, since it could lift the heavy weights needed for programmes such as Sputnik, Luna, Vostok, Voshkod, Mars and Venera.
SS-7/SS-8
The first really successful Soviet ICBM was the SS-7, ‘Saddler’, of which 186 were deployed from 1961 until it was withdrawn in 1979 under the terms of SALT I. The SS-7 was the first Soviet missile to enter service using storable liquid fuel. It had two stages giving it a range of some 11,500 km, and was therefore the first Soviet ICBM to pose a realistic threat to the continental USA, although its relative inaccuracy (it had a CEP of 2.8 km) restricted it to counter-value targets.
It was long a feature of Soviet military philosophy that an ambitious programme was backed up by a much less demanding and technically safer system, which in this case was the SS-8, ‘Sasin’. Only twenty-three SS-8s were ever deployed, and they had a limited life from 1965 to 1977.
SS-9/SS-10
The SS-9, ‘Scarp’, was the first of the second generation of Soviet ICBMs: a heavy, silo-based missile which became operational in 1966. Numbers
peaked
at 313 in 1970, remaining at this level until 1975, when retirements began, the last of the type being withdrawn in 1979. Four versions were known: the first to enter service was Mod 1, which had a 20 MT warhead, while Mod 2, the principal production version, had a 25 MT warhead – by far the most powerful warhead ever to achieve operational status in any country. The Mod 3 was a special version which was used to test the Fractional Orbital Bombardment System (FOBS), which was designed to attack the USA from the south-east; it caused considerable concern in the Pentagon. Mod 4 carried three MRVs, which impacted with the same spread as a typical USAF Minuteman missile complex, although it never actually entered service, the mission being allocated to the SS-11 Mod 3 instead.
The SS-10, ‘Scrag’, was the insurance against the failure of the SS-9. This huge missile, which used cryogenic fuels, was shown at the 1968 Red Square parade but never entered service.
SS-11
The two-stage SS-11, ‘Sego’, used storable liquid propellant and entered service in 1966, eventually serving in three principal variants. Mod 1 had a single 950 kT warhead, Mod 2 had increased range and throw weight, as well as penetration aids and a more accurate warhead, while Mod 3 carried three 200 kT MRVs, the first such system to be fielded by the USSR, with a foot-print virtually identical with that of Minuteman silos. The SS-11 had a long life, with just over half being replaced by the SS-17 and SS-19 in the late 1970s, while the balance of 420 remained until 1987, when they were replaced progressively by the road-mobile SS-25.
SS-13
Developed concurrently with the SS-11, the SS-13, ‘Savage’, was the first solid-fuel Soviet ICBM, and had an unusual construction with three stages linked by open Warren-girder trusses – a configuration matched only by the earlier SS-10. There were claims in the early 1970s that the SS-13 was being used in a mobile role, but these were never substantiated. The USSR claimed that the SS-25 was a modified version of the SS-13 (which was permitted under SALT II), and flew two missiles in 1986 to demonstrate that this was the case to the USA. Only sixty SS-13s entered service, and the production and maintenance of such a small number must have been very expensive. However, it must be assumed that it played a useful role in the Soviet nuclear force, as the SS-13 remained in service from 1972 until past the end of the Cold War.
SS-17
The SS-17, ‘Spanker’, which used storable liquid propellant, was developed in parallel with the SS-19 as a replacement for the SS-11 and was in service
from
1975 to 1990. It was the first Soviet ICBM to be launched by using a gas generator to blow the missile out of the silo, with ignition taking place only when the missile was well clear. Known as the ‘cold-launch technique’, this method minimized damage to the silo and enabled it to be reused. This caused considerable alarm in the United States, as it was seen to indicate a plan for a nuclear war lasting several days, if not weeks. The second innovation was that several versions carried MIRVs, the first operational Soviet ICBMs to do so: Mods 1 and 3 carried four 200 kT MIRVs, but the Soviets, as always, hedged their bets, and the SS-17 Mod 2 carried a single 3.6 MT warhead.
SS-18
The SS-18, ‘Satan’, the successor to the SS-9, was by far the largest ICBM to be fielded by either of the two superpowers, and its throw weight of 8,800 kg was the greatest of any Cold War missile. Starting in 1975, it was deployed in former SS-9 silos, which were modified and upgraded to take the new missile. Mods 1 and 3 both had a single large 20 MT warhead, while Mods 2 and 4 each had ten 500 kT MIRVs. The SS-18 was described by the USA as ‘extremely accurate’ and ‘designed to attack hard targets, such as US ICBM silos’. Also, according to US sources, the SS-18 force was capable of destroying ‘65–80% of the US ICBM force, using two warheads against each. Even after such an attack, there would still be over 1,000 SS-18 warheads available for further strikes against US targets.’
1
SS-19
The SS-19, ‘Stiletto’, was developed in parallel to the SS-17 and entered service in 1971, with a peak deployment of 360; it was the most widely used Soviet ICBM of its generation. It was a hot-launch missile, although it was housed in a canister which reduced silo damage. Various versions of the missile were developed, but the service version was the Mod 3, with six 550 kT MIRVs, each with a CEP of 400 m, which, again according to US sources, meant that ‘while less accurate than the SS-18, [it had] significant capability against all but hardened silos. It could also be used against targets in Eurasia.’
2
It would therefore appear safe to assume that the SS-19 was targeted against counter-force targets, such as reasonably hardened military targets, but not against ICBM silos, which were the task of the SS-18.
SS-24
The SS-24, ‘Scalpel’, was fielded in two launch modes, the Mod 1 being rail-mobile, while Mod 2 was silo-based. The actual missiles in each variant were virtually identical, being ten 500 kT MIRVS with a range of 10,000 km and a CEP of 200 m. Mod 1 was deployed in trains with three launchers each, with three rail garrisons, all in Russia; there were four trains each at
Kostromo
and Krasnoyarsk and three trains at Bershet. Fifty-six of the silo-launched version (Mod 2) were deployed, split between one site in Russia (ten silos) and one site in the Ukraine (forty-six silos).
SS-25
The SS-25, ‘Sickle’, was the last Soviet ICBM to be fielded during the Cold War. It was a single-warhead missile, carrying one highly accurate 550 kT warhead, and entered service in 1985. At the end of the Cold War 288 missiles were split between nine sites, with further missiles being deployed up to 1994. The missile was road-mobile, but was normally housed in a garage with a sliding roof which could be opened for an emergency launch. Given the necessary warning, however, the fourteen-wheel TELs were deployed to pre-surveyed sites in forests, where they were raised on jacks for stability during launch.
The SS-25 missile was contained in a large cylindrical canister, and the system was reloadable, highly survivable and capable of rapid retargeting. This led US sources to speculate that it was designed for use in a protracted nuclear war as a reserve weapon, when it would ride out the first wave of US attacks on the Soviet nuclear arsenal and then retaliate against surviving targets, which could be selected and set into the warhead at the time. It was during the flight testing of the SS-25 that the Soviets first used encryption on their telemetry down-links, which caused the US to claim that they were acting in contravention of the SALT II agreement.
BASING
The original German A-4 missile employed a brilliantly simple road-mobile system, in which the missile was carried on a four-wheeled trailer known as a
Meillerwagen
. When the missile was to be launched, the
Meillerwagen
raised it to the vertical and then lowered it on to a small launch platform. Each site had a crew of 136 men, with many more men and vehicles in the logistics chain.
The Germans also gave active consideration to launching the A-4 missile from a train. According to a 1944 plan, each train would carry six ready-to-use missiles, and include an erector–launcher car, seven fuel-tanker cars, a generator car, a workshop, a spares car and several cars for the crew. On top of this, however, the train would also carry all the vehicles normally associated with a missile battery, in order that the unit could dismount from the train and operate independently of it, which brought the whole battery up to the unwieldy total of seventy to eighty freight cars, probably requiring at least two separate trains. Separate logistic trains were planned to bring further supplies of fuel and missiles. Prototype trains were running before
the
end of the war, but the system was not a practicable proposition in view of the air supremacy of the Allies, for whom all trains were a high-priority target.
3
ICBM forces were originally built to threaten the opponent’s civil population, which in itself was not a difficult task: the warheads were relatively inaccurate, but the cities were large and the warheads powerful. It was obviously highly desirable, from both political and military viewpoints, to defend the population from this threat, in the same way that bombers had been opposed by a mixture of fighters and anti-aircraft guns during the recent war. It was not feasible at the time to intercept incoming ICBMs, so the only defence was to attack the ICBMs at their source, which could be done only by conducting a pre-emptive strike with other ICBMs. Thus the position was rapidly reached where the ICBMs’ principal target was the other side’s ICBMs, moving on to other missions only when that first battle had been decided. It was therefore necessary to optimize the attacking potential of one’s own missiles while ensuring their survivability in the face of an opponent’s first strike. There were four possibilities:
• superhardened silos, which would withstand even the most powerful incoming warhead;
• using a greater number of silos than missiles, so that the opponent would waste warheads on empty silos;
• making the missiles mobile, as the Germans did, so that the enemy could not locate them;
• using anti-ballistic-missile (ABM) defences.
The essence of the problem can be illustrated by a simplified example in which the aggressor (A) has 100 ICBMs, each with ten warheads, while the other side (B) has 500 ICBMs, each with three warheads. (For the purpose of this example, all missiles and warheads are perfectly available and reliable, and each warhead will kill one silo.) Thus A is capable of destroying 1,000 silos, and if he carries out a pre-emptive strike he requires to use only fifty missiles, leaving B with no missiles. A still has fifty missiles and is clearly the winner. If, however, B builds another 500 silos, but no more missiles, and spreads his 500 ICBMs randomly among the 1,000 silos, A, not knowing which silos are occupied, must attack all 1,000. Both sides then end up with zero ICBMs, which is a better outcome for B than the first, but is unsatisfactory from a military point of view. But if B now builds a total of 2,000 silos, half his missiles (i.e. 250) must survive the attack.