R39

R39 may refer to:

R-39 may refer to:

R-39 Rif

The R-39 Rif (NATO reporting name: SS-NX-20 Sturgeon; bilateral arms control designation: RSM-52 ) was a submarine-launched ballistic missile (SLBM) that served with the Soviet Navy from its introduction in 1983 until 1991, after which it served with the Russian Navy until 2004. The missile had GRAU indices of 3M65, 3M20, and 3R65. It was carried on board Typhoon-class submarines.

An intercontinental missile, the R-39 had a three-stage solid-fuel boost design with a liquid-fuel post-boost unit carrying up to ten multiple independently targetable reentry vehicle warheads. Like other SLBMs the initial launch was powered by a gas generator in the bottom of the firing tube. During the missile's passage through the water additional motors produce a gaseous wall around the missile, reducing hydrodynamic resistance. The launch system was designated "D-19".

Development

Development work began at NII Mashinostroyeniya in 1971 and the design gained official approval in 1973. Initial test flights from 1979 found problems in the solid-fuel boost engines, over half of the early flights failed. Later tests aboard a modified Typhoon-class submarine were more successful and deployment began in May 1983, with 20 missiles in each submarine. At full deployment, 120 missiles were deployed with 1,200 total warheads.