By the mid-1950s, it became clear that American long-range bombers in the near future would not be able to guarantee the delivery of atomic bombs to targets in the USSR and the countries of the Eastern bloc. Against the background of the strengthening of the Soviet air defense system and the appearance of its own nuclear weapons in the USSR, the United States began the creation of intercontinental ballistic missiles, invulnerable to air defense systems, and also launched research into the creation of anti-missile systems.
In September 1959, the first missile squadron of SM-65D Atlas-D ICBMs began deploying at Vandenberg Air Force Base. The rocket with a launch weight of 117.9 tons was capable of delivering a W49 thermonuclear warhead with a capacity of 1.45 Mt to a range of more than 9,000 km. Although the Atlas was superior in a number of parameters to the first Soviet R-7 ICBM, just like on the Seven, a long prelaunch preparation and refueling with liquid oxygen were required for launch. In addition, the first American ICBMs at the launch site were stored in a horizontal position and were very poorly protected in engineering terms. Although more than a hundred Atlas missiles were on alert at the peak of their deployment, their resistance to a sudden disarming nuclear strike was rated low. After the massive deployment on American territory of the HGM-25 Titan and LGM-30 Minuteman ICBMs, placed in highly protected silo launchers, the issue of combat stability was resolved. However, in the conditions of the growing nuclear missile arms race, the United States needed additional trump cards. In 1956, US President D. Eisenhower approved a plan to create a naval strategic nuclear missile system. At the same time, at the first stage, the deployment of ballistic missiles was envisaged both on submarines and on missile cruisers.
In the 1950s, American chemists managed to create effective formulations of solid jet fuel suitable for use in missiles for various purposes. In addition to anti-aircraft and anti-submarine missiles, the United States has been actively working on solid-propellant ballistic missiles from the very beginning. As you know, rockets with a jet engine running on solid fuel, compared to a liquid engine, which uses two components stored separately from each other: liquid fuel and an oxidizer, are much easier and safer to operate. Leakage of liquid rocket fuel and oxidizer is likely to lead to an emergency: fire, explosion, or poisoning of personnel. US Navy experts recommended abandoning the option of creating a ballistic missile for submarines (SLBMs) based on a medium-range liquid-propellant missile PGM-19 Jupiter, since the presence of missiles with explosive volatile propellants and an oxidizer on the boat was considered an excessive risk. In this regard, the leadership of the US Navy applied to the Department of Defense for permission to independently order the development of a rocket for the fleet.
Almost simultaneously with the design of the LGM-30 Minuteman solid-fuel ICBM, Lockheed began work on a medium-range ballistic missile intended for deployment on nuclear submarines. The contract for the creation of a solid-propellant propulsion system was concluded with Aerojet-General. Taking into account the increased loads during the "mortar" launch from the underwater position, the rocket body was made of heat-resistant stainless steel. The engine of the first stage, running on a mixture of polyurethane with the addition of aluminum powder (fuel) and ammonium perchlorate (oxidizer), developed a thrust of 45 tons. The engine of the second stage developed a thrust of more than 4 tons and was equipped with a mixture of polyurethane with a copolymer of polybutadiene, acrylic acid and an oxidizing agent. The operating time of the 1st stage engine - 54 s, the 2nd stage - 70 s. The second-stage engine had a thrust cut-off device, due to which it was possible to adjust the launch range. The rocket was controlled using annular deflectors installed on each of the nozzles and articulated with hydraulic drives. The rocket is 8, 83 m long and 1, 37 m in diameter, weighed about 13 tons when loaded.
Flight tests of the prototype of the first American SLBM began in September 1958 at the launch site of the Eastern Missile Range, located at Cape Canaveral. At first, the tests were unsuccessful, and it took five launches for the rocket to fly normally. Only on April 20, 1959, the flight task was completed in full.
The first carrier of UGM-27A Polaris A-1 missiles were specially built nuclear submarines of the "George Washington" type. The lead boat in the series, USS George Washington (SSBN-598), was handed over to the Navy in December 1959. In total, the US Navy received five nuclear missile boats of this type from December 30, 1959 to March 8, 1961. The general layout of the George Washington-class nuclear-powered missile-carrying submarines with vertical silos located behind the wheelhouse turned out to be very successful and became a classic for strategic submarines.
The rapid construction of the first American nuclear-powered ballistic missile submarines (SSBNs) was facilitated by the fact that "George Washington" was created on the basis of the project of a nuclear-powered torpedo boat of the "Skipjack" type. This approach made it possible to shorten the construction time of the SSBN series and save significant financial resources. The main difference from the "Skipjack" was the 40-meter missile compartment, inserted into the hull behind the wheelhouse, which housed 16 missile launch silos. SSBN "George Washington" had an underwater displacement of slightly more than 6700 tons, hull length - 116, 3 m, width - 9, 9 m. Maximum underwater speed - 25 knots. The working depth of the immersion is 220 m.
On July 20, 1960, a ballistic missile was successfully launched from the George Washington SSBN, which was at that time submerged, near Cape Canaveral, for the first time in the world. Less than two hours later, a second rocket was successfully launched. The missiles could be launched from a depth of no more than 25 m, at a speed of no more than five knots. Prelaunch preparation for the launch of the first rocket lasted about 15 minutes after receiving the appropriate order. The interval between missile launches was 60-80 s. The preparation of missiles for firing and control of their technical condition was provided by the Mk.80 automated control system. During the launch, the rocket was ejected from the launch shaft with compressed air at a speed of up to 50 m / s, to a height of about 10 m, after which the first stage main engine was turned on.
Autonomous inertial control equipment Mk I weighing about 90 kg ensured the output of the "Polaris" on a given trajectory, stabilization of the rocket in flight and the start of the second stage engine. A fully autonomous inertial guidance system with a launch range of 2200 km provided a circular probable deviation (CEP) of 1800 m. However, for a number of reasons, the missiles of the first series were not recommended to be used against targets located at a distance of more than 1800 km. That, when striking in the depths of Soviet territory, forced nuclear-powered missile ships to enter the zone of action of the anti-submarine forces of the USSR Navy.
As a combat load, the rocket carried a W47-Y1 monoblock thermonuclear warhead weighing 330 kg and a capacity of 600 kt, which, taking into account the CEP, made it effective against large area targets. Taking into account the relatively short flight range of the Polaris A-1 missiles, combat patrols of boats equipped with these missiles took place mainly in the Mediterranean Sea and in the North Atlantic. To reduce the time required for the arrival of American SSBNs in the position area and optimize operating costs, an agreement was signed with the British government in 1962 to create an advanced base in Holy Lough in the Gulf of the Irish Sea. In response, the Americans pledged to provide Polaris missiles designed to arm British Resolution-class submarines.
Despite some shortcomings, the boats of the "George Washington" type have seriously strengthened the American nuclear missile potential. American SSBNs looked much more advantageous in comparison with the first Soviet nuclear-powered strategic missile submarine cruisers (SSBNs), project 658, which originally housed three R-13 liquid-propellant ballistic missiles with a launch range of 600 km. Moreover, missiles of this type could only be launched on the surface, which significantly reduced the chances of completing a combat mission. Surpass the American SSBN "George Washington" with SLBM "Polaris A-1" managed only SSBN pr. 667A with 16 SLBMs R-27. The leading Soviet boat of this type entered service in 1967. The R-27 missile was equipped with a 1 Mt monoblock thermonuclear warhead and had a launch range of up to 2500 km from a KVO of 1, 6-2 km. However, unlike the American solid-propellant SLBM Polaris, the engine of the Soviet rocket ran on liquid toxic fuel and a caustic oxidizer that ignited flammable substances. In this regard, during operation, accidents with human casualties were not uncommon, and one boat of Project 667AU perished as a result of a rocket explosion.
Although the UGM-27A Polaris A-1 SLBM was superior to its Soviet counterparts at the time of its appearance, this missile did not fully satisfy the American admirals. Already in 1958, simultaneously with the start of flight tests of the first serial modification, the development of the UGM-27B Polaris A-2 version began. The main emphasis in the creation of this rocket was placed on increasing the launch range and throw weight while maintaining maximum continuity with the Polaris A-1, which significantly reduced technical risk and costs. The most radical innovation used in the new modification of Polaris was the use of fiberglass reinforced with a composite resin in the creation of the second stage engine case. This in turn made it possible to make the second stage easier. The resulting mass reserve made it possible to place a larger supply of solid fuel on board the rocket, which in turn increased the launch range to 2800 km. In addition, the UGM-27B Polaris A-2 became the first American SSBN to use missile defense penetration means: six false warheads and dipole reflectors - used on a part of the trajectory outside the atmosphere and in the transition to the atmospheric section of the descending branch, as well as jammers. included in the initial part of the atmospheric section. Also, to counteract the means of missile defense, after the separation of the warhead, a system of withdrawing the second stage to the side was used. This made it possible to avoid aiming anti-missiles at the second-stage propulsion system, which has a significant EPR.
At the start, the rocket was thrown out of the mine not with compressed air, as in the case of the Polaris A-1, but with a steam-gas mixture produced by a gas generator, which is individual for each rocket. This simplified the missile launch system and made it possible to increase the launch depth to 30 m. Although the main launch mode was a launch from a submerged position, the possibility of launching from a surfaced boat was experimentally confirmed.
A rocket with a length of 9, 45 m, according to various sources, had a launch weight of 13,600 to 14700 kg. She carried a thermonuclear warhead W47-Y2 with a capacity of up to 1.2 Mt. According to information published by the Lockheed Martin corporation, the KVO "Polaris A-2" was 900 m, according to other sources, the hitting accuracy was at the level of "Polaris A-1".
Etienne Allen-class submarines were armed with Polaris A-2 missiles; each of the five SSBNs of this project had 16 silos with SLBMs. Unlike submarines of the "George Washington" type, the submarine missile carriers of the new project were developed as an independent design and were not alterations from nuclear torpedo submarines. SSBN "Etienne Allen" became the largest, which made it possible to improve the living conditions of the crew. Its length is 124 m, width - 10, 1 m, underwater displacement - 8010 tons. The maximum speed in the submerged position is 24 knots. The working depth of immersion is up to 250 m. The maximum achieved during the tests is 396 m. The significant increase in the immersion depth achieved in comparison with the SSBN "George Washington" was due to the use of new grades of steel with a high yield strength for the construction of a strong hull. For the first time in the United States, Etienne Allen-class nuclear-powered submarines have implemented measures to reduce the noise of a power plant.
The lead missile submarine USS Ethan Allen (SSBN-608) entered service on November 22, 1960 - that is, less than a year after the fleet took over the USS George Washington SSBN (SSBN-598). Thus, in the late 50s and early 60s, the United States was simultaneously building two submarine strategic missile carriers, which demonstrates the scope with which preparations for a nuclear war with the Soviet Union were carried out.
In the period from the second half of 1962 to the summer of 1963, all Aten Allen-class SSBNs became part of the 14th submarine squadron of the US Navy. They conducted combat patrols mainly in the Mediterranean Sea. From here it was possible to deliver nuclear strikes against cities in the European part and the southern regions of the USSR. Also, the UGM-27B Polaris A-2 SLBMs were equipped with the first 8 Lafayette-class boats.
The evolutionary version of the development of the Aten Allen-class submarines was the Lafayette-class SSBN. They managed to significantly reduce the acoustic signature, as well as improve stability and controllability during missile launches.
The submarine USS Lafayette (SSBN-616) officially entered service on 23 April 1963. Its length was almost 130 m, the width of the hull was 10.6 m, the underwater displacement was 8250 tons. The maximum underwater speed was 25 knots, the immersion depth was 400 m.
The difference between the boats of this project and the Aten Allen submarines was a more elaborate design and significant modernization potential, which subsequently made it possible to equip Lafayette-class SSBNs with more advanced ballistic missiles. However, despite the relatively high flight and operational characteristics, serious problems arose with the combat readiness of the UGM-27A Polaris A-1 and UGM-27B Polaris A-2 missiles. After several years of operation, it became clear that due to the design flaws of the W47-Y1 and W47-Y2 thermonuclear warheads, there is a high probability of their failure. In the 60s, there was a moment when up to 70% of the warheads deployed on Polaris A-1/2 missiles had to be removed from combat duty and sent for revision, which of course seriously reduced the strike potential of the naval component of the American Strategic Nuclear Forces (SNF) …
To confirm the combat characteristics of the Polaris SLBM and the operational reliability of thermonuclear warheads on May 6, 1962, as part of Operation Fregat, which in turn was part of a series of nuclear weapons tests Dominique, from the Etienne Alain boat, located in the southern part of the Pacific Ocean, the UGM-27B Polaris A-2 ballistic missile was launched. A missile with military equipment, having flown more than 1890 km, exploded at an altitude of 3400 m, a few tens of kilometers from the Pacific Johnson Atoll, which had a control and measuring complex with radar and optical means. The explosion power was 600 kt.
In addition to the equipment located on the atoll, American submariners from the Medregal (SS-480) and USS Carbonero (SS-337) boats, which were submerged at a distance of more than 30 km from the epicenter, observed the tests through the periscope.
Since the Polaris A-1 / A-2 missiles and warheads for them were created in a great hurry, there were a number of technical flaws in their design. In addition, the developers did not have the opportunity to quickly implement the latest technical achievements in full. As a result, the UGM-27C Polaris A-3 became the most advanced missile in the Polaris family of SLBMs. Initially, the leadership of the Ministry of Defense opposed the creation of this modification, but due to the design features of the missile silos, submarines of the George Washington and Etienne Alain types were unsuitable for equipping with promising UGM-73A Poseidon-C3 missiles.
In the third serial modification of Polaris, thanks to the analysis of the experience of operating missiles during combat patrols and the use of a number of fundamental technological improvements: in electronics, materials science, engine building and solid fuel chemistry, it was possible not only to improve the reliability of the rocket, but also to significantly increase its combat characteristics. The new modification of SSBNs has demonstrated an increase in range, firing accuracy and combat effectiveness in tests. For the modification of Polaris A-3, on the basis of research by specialists from the Massachusetts Institute of Technology, General Electric and Hughes created a new inertial control system, which had 60% less mass than the equipment of the Polaris A-2 SLBM. At the same time, much attention was paid to increasing the resistance of electronics to ionizing radiation and electromagnetic impulses.
The Polaris A-3 SLBM largely inherited the design features and layout of the Polaris A-2. The rocket was also two-stage, but its body was made of fiberglass by winding fiberglass with epoxy resin gluing. The use of fuel with a new formulation and increased energy characteristics, as well as a decrease in the weight of the engine and on-board equipment of the rocket led to the fact that practically without changing the geometric dimensions in comparison with the previous model, it was possible to significantly increase the firing range while simultaneously increasing the throw weight.
With a length of 9, 86 m and a diameter of 1, 37, the rocket weighed 16,200 kg. The maximum launch range was 4600 km, KVO -1000 m. Throw weight - 760 kg. The UGM-27C missile was the first in the world to be equipped with a multiple warhead of a dispersive type: three Mk.2 Mod 0 warheads, each of which had a 200 kt W58 thermonuclear warhead. Thus, when hitting an area target, the destructive effect of three 200 kt warheads was significantly greater than from one 600 kt. As you know, to increase the affected area in a nuclear explosion by 2 times, the power of the charge must be increased by 8 times. And in the case of using scattering warheads, this was achieved due to the mutual overlap of their affected area. In addition, it was possible to increase the likelihood of destroying highly protected targets such as silo launchers for ballistic missiles. In addition to warheads, the missile carried missile defense breakthroughs: dipole reflectors and inflatable decoys.
Flight tests of the Polaris A-3 prototypes began in April 1963 at the Eastern Missile Range. Test launches from the SSBN lasted from May 1964 to April 1968. The considerable duration of the test stage was associated not only with the desire to "bring to mind" the new missile as much as possible, but also with a large number of missile submarines equipped with the new SLBM. Thus, UGM-27C missiles were re-armed with all SSBNs of the "Jord Washington" type, of the "Etienne Allen" type and 8 submarines of the "Lafayette" type. One boat USS Daniel Webster (SSBN-626) has been armed with Polaris A-3 since its construction. In addition, the British Resolution-class SSBNs were armed with the third Polaris modification.
As part of the expansion of "nuclear deterrent" missiles modification Polaris Mk.3 planned to equip the ships of the US Navy and NATO countries. In total, American strategists wanted to deploy up to 200 missiles on surface carriers. In the period from 1959 to 1962, during the overhaul of old ships and during the construction of new ones, 2-4 missile silos were installed on American and European cruisers. So, 4 silos for the Polaris Mk.3 received the Italian pre-war cruiser Giuseppe Garibaldi. In the fall of 1962, the Polaris was launched from the cruiser, but the Italians never received combat missiles with thermonuclear warheads. After the Caribbean Crisis, the Americans reconsidered their views on the deployment of strategic nuclear weapons outside their territory and abandoned plans to deploy ballistic missiles on surface ships.
According to American data, the combat service of the Polaris A-3 SLBM in the US Navy lasted until October 1981. After that, the carrier boats of this missile system were withdrawn from the fleet or converted into torpedo or special-purpose submarines. Although in the early 70s the commissioning of nuclear missile boats with UGM-73 Poseidon C-3 SLBMs began, the UGM-27C Polaris A-3 missile is a successful example of evolutionary development with a significant improvement in combat characteristics.
In total, from 1959 to 1968, Lockheed Corporation built 1,153 Polaris missiles of all modifications. Including: “Polaris A-1” - 163 units, “Polaris A-2” - 346 units, “Polaris A-3” - 644 units. The missiles being removed from service were used to test American systems for radar detection of SLBM launches, imitating the Soviet R-21 and R-27 missiles. In the late 60s and early 70s, a network of radars designed to record missile launches from submarines was deployed on the East and West coasts of the United States. Also, on the basis of the Polaris A-3 SLBM, a STARS launch vehicle (Strategic Target System) with a third solid-propellant stage ORBUS-1A was created. Based Infrared System - space-based infrared system).
The STARS launch vehicle on November 17, 2011 was also used in flight tests of the HGB (Hypersonic Glide Body) hypersonic glide body as part of the AHW (Advanced Hypersonic Weapon) program for creating hypersonic weapons. The hypersonic glider successfully separated from the third stage of the carrier and, moving in the upper atmosphere over the Pacific Ocean along a non-ballistic gliding trajectory, less than 30 minutes later fell in the area of the aiming point located on the territory of the Reagan Proving Ground (Kwajalein Atoll), 3700 km from the launch site. According to unconfirmed information, during the flight, a speed of about 8 M. was achieved. The goal of the program for creating hypersonic weapons is the possibility of destruction of conventional warheads at a distance of up to 6,000 km, after 30-35 minutes from the moment of launch, while the accuracy of hitting the target should be no more than 10 meters. A number of experts believe that the destruction of a target with the help of AHW will be carried out as a result of the kinetic effect of a warhead flying at high hypersonic speed.
