Belgorod is a nuclear-powered submarine built by Sevmash under Project 09852. Credit: FriskyAnYantos/Wikimedia Commons.
Belgorod can be armed with six Poseidon nuclear torpedoes, earlier called Status-6. Credit: Russian DoD/Wikimedia Commons.
The K-329 Belgorod nuclear-powered submarine is based on Oscar II class nuclear submarines. Credit: US Department of Defense/Wikimedia Commons.

K-329 Belgorod is a class of specialised intercontinental unmanned nuclear-powered submarines built under Project 09852 for the Russian Navy. It was built by Sevmash, a shipbuilding company that is part of Russian joint stock company United Shipbuilding (USC).

The submarine is designed to address various research missions and conduct search and rescue operations. It also offers nuclear strike capabilities and support in deterring potential adversaries.

Deployed in the Pacific Ocean within the Russian Pacific Fleet, the submarine has the capability to carry out missions in any part of the ocean.

The Belgorod submarine successfully conducted a series of trial launches testing the mass-dimensional model of the Poseidon torpedo in January 2023. The trials tested the submarine’s performance at various depths after the launch.

A new division containing Belgorod, Khabarovsk and other submarines will come into operation in Kamchatka within the submarine forces of the Russian Pacific Fleet in 2025.

K-329 Belgorod submarine development details

Project 09852 was developed by the Rubin Central Design Bureau for Marine Engineering, a submarine development company of USC. The keel-laying ceremony was held in December 2012.

K-329 Belgorod was initially presented as a research submarine for carrying out diverse explorations, search-and-rescue operations, equipment installation and inspections, new research apparatus testing, and monitoring underwater transport routes.

The central section of the submarine was redesigned in 2017 to replace the missile compartment with a longer hold to carry deep-water rescue and autonomous underwater drones. The redesign made it the largest submarine of the Russian Navy by length, which extended from the initial 154m to 184m.

The submarine was subsequently floated out as the first carrier of deep-water nuclear-propulsion Poseidon drones from the Sevmash shipyard in Severodvinsk in April 2019.

The sea trials for the submarine were initiated in the White Sea in June 2021 and concluded in July 2021. The submarine was commissioned into the Russian Navy in July 2022.

K-329 Belgorod nuclear-powered submarine details

Belgorod is a special-purpose and research submarine based on Oscar II class submarines. It is 184m long and 18.2m wide and has a displacement of more than 14,700 tonnes (t) when surfaced and 24,000t when submerged.

The submarine can dive up to a depth of 520m and can stay underwater for approximately four months. It can carry an AS-15 deep-sea nuclear station.

It can host deep-diving nuclear-powered midget submarines to conduct covert deep-sea operations beneath the ocean’s surface. Midget submarines can target subsea infrastructure, including sensor arrays, pipelines, and internet cables.

Propulsion

The submarine is propelled by two pressurised water reactors OK-650M.02 having a capacity of 190MW, which drives two steam turbines and twin screws. It can travel at speeds of more than 32 knots.

Armament aboard

The Belgorod nuclear submarine can carry six Poseidon nuclear torpedoes, earlier named Status-6, with six 533mm torpedo tubes.

Poseidon nuclear torpedoes features

The Poseidon torpedo is an intercontinental, nuclear-powered, nuclear-armed autonomous torpedo with an estimated length of 24m and a diameter of 1.6m. It can operate at a maximum depth of 1,000m and has an endurance of 10,000km and approximately 100 hours.

It is the world’s largest torpedo and can travel at a speed of 185km/h. It features long-range internal guidance sensors, possibly with external or abort features and obstacle avoidance sonars.

The torpedo can carry 100Mt of nuclear warheads and is powered by a nuclear reactor, which drives a pumpjet. It is a strategic nuclear torpedo weapon that may target naval bases and coastal cities.