RK-55 Relief

RK-55 Relief was a Soviet submarine-launched cruise missile (SLCM) developed during the late Cold War. Designed by the Novator Design Bureau for the Soviet Navy, it was intended as a strategic counterpart to the American BGM-109 Tomahawk. The missile entered service in the mid-1980s, providing a long-range, nuclear-capable strike option from specialized submarines and surface vessels.

Overview

The RK-55 Relief was a key component of the Soviet strategic forces, conceived under the broader SS-N-21 Sampson NATO reporting name system. Its primary mission was to deliver a thermonuclear weapon against high-value inland targets, such as command centers and industrial hubs within NATO member states. The system shared technological lineage with the land-based RK-55 Granat (SSC-X-4 Slingshot) and was part of a family of weapons developed by the Novator Design Bureau. Deployment of the RK-55 Relief significantly enhanced the Soviet Navy's stand-off attack capabilities, complementing the arsenal of ballistic missile submarines like the Project 667BDR Kalmar.

Development and design

Development of the RK-55 Relief began in the late 1970s under the direction of chief designer Lev Lyulyev at the Novator Design Bureau, in response to the U.S. deployment of the BGM-109 Tomahawk. The design leveraged experience from earlier Soviet cruise missile projects, including the P-120 Malakhit. It was powered by a compact turbofan engine and utilized a sophisticated guidance system combining an inertial navigation system (INS) with TERCOM (Terrain Contour Matching) for high accuracy over its 3,000-kilometer range. The missile was engineered to be launched from standard 533 mm torpedo tubes on modified nuclear attack submarines, requiring specialized launch containers. Key production and testing involved facilities like the State Mechanical Engineering Design Bureau and ranges such as the Nenoksa State Central Naval Testing Range.

Operational history

The RK-55 Relief entered service with the Soviet Navy in 1984, initially deployed aboard the converted Project 667AT Grusha (Yankee Notch) submarines, which could carry up to 32 missiles. Operational patrols began in the Barents Sea and the Sea of Okhotsk, posing a new strategic challenge to United States Northern Command and United States European Command. The system's existence was formally acknowledged in the context of arms control negotiations like the Intermediate-Range Nuclear Forces Treaty (INF Treaty), which led to the elimination of its land-based counterpart. Following the dissolution of the Soviet Union, remaining missiles were inherited by the Russian Navy, though their operational status became uncertain. Some reports suggest limited use in later Russian military exercises, such as those monitored by the Organization for Security and Co-operation in Europe.

Variants

* RK-55 Relief (SS-N-21 Sampson): The original submarine-launched variant for the Soviet Navy. * RK-55 Granat (SSC-X-4 Slingshot): The road-mobile, ground-launched version for the Soviet Strategic Rocket Forces, deployed from MAZ-543 vehicles. This variant was eliminated under the INF Treaty. * 3M10: The common GRAU index for the missile family. * An experimental air-launched version was reportedly tested from aircraft like the Tupolev Tu-95MS, though it did not enter serial production.

Operators

* Soviet Union: The primary operator through the Soviet Navy until 1991. * Russia: Inherited an unknown number of missiles and launch platforms after 1991, with service in the Russian Navy. * Ukraine: Reportedly inherited a small number of missiles or related components following the split of the Black Sea Fleet, but they were never operationalized by the Armed Forces of Ukraine.

Category:Cruise missiles of the Soviet Union Category:Submarine-launched cruise missiles Category:Cold War weapons of the Soviet Union