R-29RMU2.1 Layner

The R-29RMU2.1 Layner [Liner] liquid-propellant submarine-launched ballistic missile is an improved version of the previous R-29RMU2 Sineva. In fact, the "Liner" is the "Sineva" with a new front end for overcoming American ABM systems. Almost all of their differences are caused by the fact that the "Liner" can carry different load options - from ten low-power combat units to four medium ones. At the same time, in all configurations of the throw weight, there are several blocks of means for overcoming the ABM system: EW systems and false targets. The conversion from "Sineva" to "Liner" will cost the military in 40-60 million rubles, depending on the state of the rocket.

This SLBM was developed by the Makeyev Rocket Design Bureau and produced by the Krasnoyarsk Machine-Building Plant. The R-29RMU2.1 Layner was first tested in 2012 and adopted in 2014. Currently it is carried by Delta IV class submarines. Existing R-29RMU2 Sineva missiles were reportedly modified to this new standard, but these reports appear to be erroneous. There were rumors, that the State Rocket Center has considerations for re-equipment of the old R-29RM in the Liner, but this information does not look plausible enough. Firstly, the R-29RM and R-29RMU2 have many serious design differences, and secondly, the service life of even the newest R-29RM is coming to an end and processing them to the state of "RMU2.1" is simply inadvisable.

The new Russian liquid-fuel R-29RMU2 Layner Liner missile is world’s most advanced submarine-based strategic weapon with range and payload capabilities surpassing every model deployed by any other country, its developer said. The submarine-launched ballistic missile (SLBM) Liner can carry up to 12 low-yield MIRV nuclear warheads, three times as many as Sineva. It has a payload/mass ratio surpassing any solid-fuel strategic missiles designed by the US, UK, France and China, the developer Makeyev State Rocket Center said. It is very flexible in terms of what its payload can be, varying and mixing warheads of different capabilities.

The Layner is a three-stage missile wtih a throw weight of 2,800 kg. It has a maximum range of 8,300 km with full load and 12,000 km with reduced load. Each missile can carry up to 12 low-yield warheads with a yield of 100-300 kT. A distinctive feature of this missile is that warheads can be of a mixed set with various yields, a feature not present of the previous R-29RMU2 Sineva missile. The new missile is equipped with improved systems that allow to anti-ballistic missile defenses. For this role it carries array of decoys. Furthermore it can be configured to can carry fewere nuclear warheads, but more decoys. It is reported that the warheads are capable of in-flight maneuvering and re-targeting, in order to outmaneuver hostile defenses.

The Layner missile has an Astro-inertial guidance with Russian GLONASS satellite navigation system update. It has a CEP of around 350 meters. This missile can be launched from a depth of up to 55 m, while the submarine is moving at a speed of 11-13 km/h (6-7 knots). Submarine basing of the ICBMs allow surviving a the first strike once the country has been attacked. However the Russian Delta IV submarines are not as stealthy as the US or British ballistic missiles. Still though these have a higher chances of surviving than stationary silo-based systems. Furthermore these missiles have sufficient range to be fired straight from the pier, even without need for the submarines to leave their well protected bases.

The original R-29RM was launched in series production in 1986, but ten years later, due to the difficult economic situation in the country and new views on strategic submarines, the production was curtailed. Shortly after the production of the R-29RM was discontinued, it was necessary to begin work on the creation of a new modification of this missile. The reasons are simple: the existing P-39 had almost expired shelf life, and the creation of the R-39UTTX "Bark" rocket went very badly (in the end, it never yielded results - the project was closed in favor of the R-30 Bulava). It was necessary to find something to close the "hole" in strategic armaments, after all, and the available R-29RM sooner or later would have to be written off in old age.

The original R-29RM was launched in the series back in 1986, but ten years later, due to the difficult economic situation in the country and new views on strategic submarines, their production was curtailed. Shortly after the production of the R-29RM was discontinued, it was necessary to begin work on the creation of a new modification of this missile. The reasons are simple: the existing P-39 has almost expired shelf life, and the creation of the R-39UTTX "Bark" rocket went very hard (in the end, it never yielded results - the project was closed in favor of the R-30 Bulava). It was necessary to close something "hole" in strategic armaments, after all, and the available R-29RM sooner or later would have to be written off in old age.

Liner appeared suddenly. It was first reported to the general public after the submarine "Yekaterinburg" launched a new missile on May 20, 2011. "Liner" successfully struck conventional targets on the Kamchatka training range "Kura". The second copy of the R-29RMU2.1 set off for the flight from the Tula boat and also, in training, destroyed the assigned targets in Kamchatka. After that, representatives of the Ministry of Defense and the SRC them. Makeyev announced the successful completion of the tests, and the missile itself was recommended for adoption.

As of 2018 a total of 6 Delta IV class submarines, equipped with ballistic missiles, are in service with the Russian Navy. It is planned that the Delta IV class submarines will be operational until at least 2030.