R-13 / SS-N-4 SARK

The R-13 was a single-stage storable liquid-propelled missile with a separable monoblock reentry vehicle. The R-13 was equipped with a single combustion chamber turbopumped rocket engine. The R-13 was the first Soviet SLBM to use such a four chambered vernier engines for flight control instead of gas or aerodynamic control surfaces. Additionally, to stabilize the missile in early flight, four aerodynamic stabilizers, considerably smaller than the fins used on the R-11FM, were used. The SS-N-4 could deliver a 2800-lb reentry vehicle a maximum operational range of 300 nm. The reentry vehicle had a nuclear warhead with a yield estimated in the west at 1.2 to 2.0 MT, though Russian sources place the yield at 1.0 MT. It had an inertial guidance system and a CEP of 1 to 2 nm according to western intelligence estimates.

The development of the D-6 with the first solid-fuel domestic SLBM was launched by the Decree of the USSR by the Council of Ministers No. 1032-492 on September 5, 1958 and was conducted under the same tactical and technical requirements. It was supposed to create a missile with the dimensions of the launcher similar to the dimensions as well as with the same sequence of design and testing of the complex as for the R-21 missile. The first version of the missile using a ballistic fuel engine was chosen for implementation for the most rapid acceptance of the missile into armament. Tests of the complex were supposed to be conducted at the Naval range at Cape Fiolent in Crimea (military unit No.99375).

On 07 November 1962, models of one of the types of missiles created for the D-6 launch complex were shown at the parade on Red Square in Moscow. The same mock-ups were shown at the parade on May 1, 1963, and then they were shown several more times, including. at the parade in Leningrad. Western observers identified the missiles as "SS-N-4 SARK". Later, the this name was transferred to the R-13 SLBM. Also, in some Western sources of 1970-1980s the rocket was identified as "SS-N-5 SERB", which was simply an error (this is the name of the R-21 missile).

Western intelligence in the 1960s was somewhat confused by the relationship between the R-11FM and R-13 programs. Despite the significant differences in the physical designs of these missiles, the R-11FM was regarded as simply the interim reduced-range version of the longer range R-13. The short range of the R-11FM missiles rendered submarines armed with this missile vulnerable to antisubmarine defense systems, highlighting the need for a longer-range system.

On 25 August 1955 the Russian government ordered the development of a sea-based ballistic missile with a range of 400-600 km capable of carrying a nuclear warhead. The D-2 launch system with R-13 missiles was authorized on 11 January 1956. In early 1956 OKB-1 NII-88 finished the the preliminary design, after which the project was transferred TO SKB-385, which conducted all further activities. The design was completed in 1957 and in December 1958 the engine tests of the R-13 missile began. Between June 1959 and March I960 fixed and dynamic platform flight tests of the R-13 were conducted at the State Central Training Site in Kapustin Yar. Submarine tests began in November 1959 and were completed in August 1960. Altogether 15 out of 19 launches were successfully carried out at the training site and 11 out 13 on submarines. During the time the R-13 missile was deployed (1960-1972) 225 out of 311 launches were conducted successfully.

The D-2 launch system and the R-13 missiles were deployed on 13 October 1961 on 629-class Golf and 658-class Hotel submarines. Several improvements were implemented thereafter, with the missiles' combat readiness increased from three to six months, and depot storage time was increased to seven years. The SS-N-4 was believed to have been assigned both a peripheral and an intercontinental mission. Peak operational deployment was reached in 1962, with phase-out from the intercontinental mission beginning in 1964 and phase-out from the peripheral mission beginning in 1967. By 1973 the missile was believed to be assigned only a peripheral mission and was carried only aboard the Golf-I Class diesel-electric submarine, which required surfacing before missile launch. The normal reaction time is 20 to 25 minutes. The reaction time under conditions of peak alert is six to eight minutes, and the allowable hold time under these conditions is about one hour.