NS Sibir icebreaker

NS Sibir (“атомный ледокол Сибирь”) is a new-generation and currently the world’s largest nuclear-powered icebreaker. “NS” stands for “nuclear ship.” The vessel is state-owned (by the Russian Federation through FSUE Atomflot) and operated by Rosatom. Atomflot provides maintenance and technical services for all Russian nuclear icebreakers and also manages the country’s special-purpose vessel fleet.

The vessel (IMO number 9774422) is Russia-flagged (MMSI 273123123) and registered in Murmansk.

Active Russian nuclear icebreakers besides NS Sibir include Rossiya (2027/Project Leader), Ural (2022), Arktika (2020), Yakutia (2024), Chukotka (2026), Leningrad (2028), Stalingrad (2030), Taymyr (1989), Vaygach (1990), Yamal (1992), and 50 Let Pobedy (2007).

Sibir is the second vessel in the “Project 22220” (LK-60Ya) class of nuclear icebreakers, a series of seven units designed and built in Russia.

Construction began with the keel-laying ceremony on May 26, 2015. The vessel (hull/yard number 05707) was launched on September 22, 2017, and officially delivered and commissioned on December 24, 2021. NS Sibir entered service in January 2022.

These ships are currently the world’s largest and most powerful icebreakers, exceeding the dimensions of the earlier “nuclear cruise ship” 50 Let Pobedy by 14 m in length and 4 m in width.

Negotiations between Atomflot and USC (United Shipbuilding Corporation) were lengthy. In 2013, the federal government allocated RUB 86.1 billion (~USD 1.3 billion) for the project. Rosatom proposed a lower cost—RUB 77.5 billion (~USD 1.2 billion)—but Baltic Shipyard declined. A new tender in December 2013 set the shipbuilding cost at RUB 84.4 billion.

Due to the vessel’s dual-draft design (8.7 m / 10.5 m), Sibir operates along the Northern Sea Route and serves both Arctic sea passages and river estuaries. Operational areas include the Barents Sea, Kara Sea, Pechora River, Yenisei estuary, and the Ob River (Gulf of Ob).

Russia’s nuclear icebreaker fleet is used exclusively in the Arctic Ocean for escorting commercial vessels and assisting research stations in ice-covered regions north of Siberia. These ships also support scientific expeditions and Arctic cruise operations. Their reactors must operate in cold waters for optimal cooling efficiency.

NS Sibir vessel details

Project 22220 nuclear icebreakers have a minimum draught of 8.6 m (28 ft) and a maximum of 10.5 m (34 ft). The dual-draft configuration enables operations in both deep-sea and shallow river environments.

Each ship carries two RITM-200 nuclear reactors generating a combined thermal output of 350 MW. Propulsion output is 110 MW. The previous-generation design delivered 60 MW (hence the “LK-60” designation). The RITM-200, developed by OKBM Afrikantov, is a pressurized water reactor producing 55 MWe. It uses up to 20% enriched uranium-235, requires refueling every 7 years, and has a planned 40-year service life. The same reactor type is used for Russia’s newest aircraft carriers (Project 23000E).

Sibir’s maximum icebreaking capability is 2.8 m (9 ft) at a cruising speed of 1.5–2 knots (2.8 km/h / 1.7 mph).

In May 2015, Russia announced plans to develop new-generation nuclear icebreakers capable of breaking ice up to 4.5 m (15 ft) thick, with propulsion power of 110 MW—nearly double that of Project 22220 units.

The steel for Sibir (“Mill 5000” thick plate) was supplied by MMK (Magnitogorsk Iron and Steel Works), one of the world’s top steel producers and supplier of over 50% of Russia’s shipbuilding steel. Mill 5000 is used in naval vessels, tankers, and ice-class ships, and is certified by Lloyd’s Register and Bureau Veritas.

The next photo shows the old NS Sibir.

The old Sibir (1977-built) was decommissioned in 1992. NS Sibir (IMO 7604491) belonged to the Arktika-class nuclear ships—the world’s largest and most powerful icebreakers of their time. The vessel was state-owned and operated by MSCO (Murmansk Shipping Company), later transferred to Atomflot.

The old icebreaker was one of ten Russian nuclear ships and one of six vessels of its class, along with the old Arktika (1975–2008), Rossiya (1982), Sovetskiy Soyuz (1990), Yamal (1992), and 50 Let Pobedy (2007).

Interestingly, the old NS Sibir was the only Russian nuclear icebreaker whose superstructure was not painted red. After retirement in 1992, the vessel remained laid up in Murmansk until at least 2012 awaiting scrapping.

NS Sibir is equipped with: 1 dining room, sauna, library, auditorium, passenger lounge, volleyball court, gymnasium, 1 indoor heated swimming pool, infirmary, 1 elevator, and 1 helipad (Mi-2 transport helicopter).

• Deadweight: 9,000 tons
• Displacement: 33,540 tons
• Clear path width: 50 m (164 ft)
• Draught: 8.6 m (min), 10.5 m (max)
• Height: 52 m (171 ft)
• Icebreaking capability: 2.8 m (9 ft)
• Ice class: 9 (highest)
• Design service life: 40 years
• Range: unlimited
• Powerplant: 2× RITM-200 reactors (175 MW each; 350 MW total)
• Propulsion: 3 shafts (110 MW combined)

Project 22220 ships have an endurance of 6 months (provisions) and 7 years (nuclear fuel).

Note: In areas with poor AIS coverage, tracking the vessel’s real-time position may not be possible.

You can view CruiseMapper’s complete list of icebreakers and icebreaking research ships in the “itinerary” section of our Icebreakers hub.