R-39 RIF / SS-N-20 “STURGEON”
In 1983 the USSR put into service the R-39 Rif or SS-N-20 Sturgeon (according to the NATO designation) SLBM missile. It was the first Soviet SLBM missile with solid-fuel propulsion, and was armed with a warhead composed by ten MIRVs (multiple independent targeting reentry vehicle), with ability to attack targets independently. Its development began in 1971, and in 1976 a Golf class diesel-electric powered ballistic submarine (SSB) was modified to test this missile. After problems with the solid-fuel boost engines, test flights did not arrive until 1980, resulting in four of them failed and two successful. The SS-N-20 missile was the main armament of the Typhoon class SSBN submarines and 120 missiles were built. Altogether they reached 1,200 MIRVs with a yield of between 200 and 300kT each, which in total were between 240 and 360 Mt of deadly load !!. In 2004 they were withdrawn from service except for a copy used for the development of the RSM-56 Bulava SLBM missile.
R-39 / SS-N-20 gallery and more info