R-36 / 8K67 (SS-9 SCARP) gallery

In April 1962, the Council of Ministers of the USSR gave orders to develop a new ICBM missile that would surpass the capabilities of the American Titan-2 ICBM missile that had just begun flight tests a month earlier. Some of the main requirements for the new missile were; use of nitrogen tetroxide as an oxidizing agent, two types of selectable monoblock warheads, an autonomous control system that allows remote control of the launch of missiles from the silo, an autonomous combined inertial control system with radio correction, additional rotation of the missiles to the desired azimuth after leaving the silo, long useful life and high combat readiness, new lighter and more resistant fuel tanks, hot pressurization of the fuel tanks and greater survivability of the missile during the first attack. It was indicated that the missile must be able to be fired within 5 and 8 minutes of receiving the order and that in the event of a crisis, for a maximum period of 10 days, the missile must be able to be fired within 1 minute after the order is given.
The missile was generically designated as “R-36/8K67” (NATO codename SS-9 Scarp). Initially, 3 versions of the missile were going to be developed, one intercontinental (ICBM), one space and one orbital (R-36O/8K69 SS-9 mod.3). The ICBM version would be developed with two different warheads, one “heavy” 8F675 type with a yield of 20 Mt (R-36/8K67 SS-9 mod.1) and one “light” 8F674 type with a blast yield of 8 Mt (R-36/8K67 SS-9 mod.2), and should have a range of 12,000 and 16,000 km respectively. It was expected that the ICBM missile would be able to carry out flight tests in late 1963 and the orbital version in September 1964. Although the design had limited the weight of the missile to 165 tons, it had to be modified in February 1963 due to the installation of a high-power warhead that reduced the range due to its greater weight. In March 1964, a requirement of 10,000 km range was set for missiles equipped with a heavy warhead, a maximum weight of 185 tons, a maximum duration of launch preparation of 4 to 5 minutes and a useful life of the missile’s fuel for at least 5 years.
The R-36/8K67 missile have two booster stages fed by bipropellant liquid formed by UDMH (asymmetrical dimethylhydrazine) as fuel and nitrogen tetroxide as oxidant. The fuel tanks are made of aluminum and magnesium alloy AMg-6N and they are mounted within a single fuel section that has intermediate partitions. The 2nd stage fuel tank was a single compartment divided into two parts, the upper one housed the oxidizer and the lower one the fuel. The 1st stage had 3 RD-250 sustaining rocket motors without afterburning plus 1 RD-68M/RD-855 control rocket motor, all with liquid propulsion, that developed 270,300 kg of thrust at sea level or 303,200 kg of thrust in vacuum. In the tail of the 1st stage (on the image), 4 solid propulsion braking rocket motors (retrorockets) were installed to brake and divert the 1st stage after separating from the 2nd. The 2nd stage had an RD-252 liquid propulsion rocket motor and an RD-69M liquid propulsion control rocket motor that developed 101,200 kg of thrust in vacuum. It also had several solid propulsion retrorockets for retraction and braking after separating the 1st stage.
The instrument compartments were made of magnesium alloys MA2-1 and VM65-1 and on the outside they were coated with a layer of thermal insulation based on sawdust and phenol-formaldehyde varnish. The entire fuselage of the missile was protected with a layer of a special radio-absorbing and heat-protective coating. In the tail section of the second stage were containers with 15 passive decoys, which were fired at the moment the warhead separated. The missile was guided by an autonomous inertial control system using high-precision gyroscopes and an electromechanical computer that controlled the synchronous emptying of the fuel tanks, range control, the normal and lateral stabilization and the cruise speed. This system proved very accurate and led to the elimination of the radio correction system. It has an automatic stabilization system and azimuthal orientation sensors.
All variants of R-36 (SS-9 Scarp) missiles were launched from 15P714 type silos located in bases that operated from 6 to 10 silo launchers. These silos were separated from each other by 8 to 10 km and their sliding type covers resisted pressures of up to 10 kg/cm2 and the radioactivity of nuclear attacks. These missiles were “hot launch”, which meant that the propellant motors ignited inside the silo, with the exhaust gases coming out through diffusers that ran from the bottom of the silo to the surface. Filling with fuel and preparing the missile for firing was a slow, complex and dangerous task and involved the participation of numerous troops and trucks, such as oxidizer tankers, nitrogen and air tankers and mobile filling stations, among many others. The missile could be launched within 4 minutes of the firing order with a maximum wind of 90 km/h in any weather condition at a temperature of between -50 and +50ºC, even after having received a nuclear attack. It had a guaranteed operability, once filled with fuel and inserted into the silo, of 7 years, with routine maintenance having to be carried out approximately every 2 years.
Launch tests of the R-36/8K67 (SS-9 Scarp) missile began in September 1963 and continued until May 1965, with 39 launches being carried out, 31 of them successful. In September 1966 the R-36 entered service with the 62nd Missile Division based at Uzhur-4, Krasnoyarsk, Russia. However, some problems with the engines continued until the end of 1967, when the missiles had already been operational for a year. A total of 258 R-36/8K67 missiles (50 SS-9 mod.1 and 208 mod.2) were operational from 1966 to 1979, when they were replaced by more modern missiles. The R-36/8K67 variant served as the basis for a civilian expendable space launch system called “Tsyklon 2A/11K67” (Cyclone). These rockets were used to put satellites of the “Kosmos” type into low orbit and were in service from October 1967 to January 1969, with 8 launches, 7 of them successful.
Development of the R-36-O (R-36orb)/8K69 (NATO codename SS-9 mod.3 Scarp FOBS) (on the image) variant began at the same time as the ICBM missile and was a highly advanced missile intended to penetrate areas that They escaped the coverage of the American Ballistic Missile Early Warning System (BMEWS). To achieve this goal, an attack system known in the West as the “Fractional Orbital Bombardment System” (FOBS) was designed. This attack was carried out with a missile equipped with a large thermonuclear warhead flying in a low altitude polar orbit from which it could attack from any direction although primarily from the southern hemisphere, an area that was not covered by the BMEWS radars. These missiles had the advantages of an unlimited range, the impossibility of predicting the area where a warhead will fall while in the orbital leg of the flight, shorter flight time to the target, greater precision at maximum distance, and the possibility of hitting a target with several missiles simultaneously from different directions.
The R-36-O/(R-36orb) missile had 3 propulsion stages, the 1st and 2nd similar to the R-36 ICBM missiles, while the 3rd stage was the “orbital” type 8F021 (on the image), that carried the 2.3 Mt 8F673 warhead, a special 8D612 braking motor of 7,700 kg of thrust in vacuum and an automatic range control system. This last system uses an analog computer to activate the braking system that it was connected to an RV-21 Kashtan radio altimeter, which measures the distance to Earth at the beginning of the orbital leg of the flight and before the start of deceleration of the orbital stage. Flight tests of the R-36-O (R-36orb)/8K69 missile began in December 1965 and concluded in May 1968. During this period, 20 launches were carried out, 16 of them successful. During these tests, some of the missiles orbited at an altitude of 396 km (apogee) above the Earth to then impact the target with great precision, as reported. These missiles entered service in August 1968, but two successful test launches of a new modernized variant designated R-36-OM/8K69M were carried out, in September 1970 and August 1971, without development progressing further. Only 18 missiles became operational and were retired in January 1983 under the SALT-2 Treaty of 1979, which prohibited the USSR and the US to deploy orbital missiles.
In July 1967, the development of a new variant of the R-36 missile began. It was called R-36P/8K67P MIRV (SS-9 mod.4) and was equipped with a multiple warhead composed of 3 MIRVs of the 8F673 or 8F677 (on the image) type with a blast yield of 2.3 MT each. These missiles were identical to the R-36/8K67 (SS-9 mod.1 and mod.2) except, of course, for the warhead and the passive decoys. The tests began in August 1968 and lasted until November 1970, with 23 test launches being carried out, all of them successful. They entered service in December 1971 and their warhead was designed in such a way that it could be mounted on R-36 missiles that were inside the silos. It is estimated that there were about 100 operational missiles in 1975, which were progressively replaced by R-36M (SS-18 Satan) missiles between 1977 and 1979.

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