View source for Arktika-class icebreaker

{{Short description|Russian class of nuclear-powered icebreakers}}
{|{{Infobox ship begin}}
{{Infobox ship image
|Ship image=RIAN archive 186141 Nuclear icebreaker Arktika.jpg
|Ship caption=Arktika in November 1980
}}
{{Infobox ship class overview
|Builders=[[Baltic Shipyard]]
|Operators=[[FSUE Atomflot]]
|Class before= 
|Class after=[[Project 22220 icebreaker]]
|Subclasses=
|Built range=1971–2007
|In service range=1975–present
|Total ships building=
|Total ships planned=
|Total ships completed=6
|Total ships cancelled=
|Total ships active=2
|Total ships laid up=
|Total ships lost=
|Total ships retired=4
|Total ships preserved=
}}
{{Infobox ship characteristics
|Hide header=
|Header caption=<ref>{{cite web|url=http://www.rosatomflot.ru/index.php?menuid=32&lang=en |title=Atomic Icebreaker Characteristics |publisher=rosatomflot.ru |access-date=9 October 2017}}</ref><ref>{{cite web|url=http://www.rosatomflot.ru/index.php?menuid=35&lang=en |title=Atomic Icebreakers Technical Data |publisher=rosatomflot.ru |access-date=9 October 2017}}</ref>
|Ship type=[[Icebreaker]]
|Ship tonnage=20-24,000 GT
|Ship displacement=23,000–25,168 tons
|Ship length={{convert|148|m|abbr=on}}
|Ship beam={{convert|30|m|abbr=on}}
|Ship height={{convert|17.2|m|ft|abbr=on}}
|Ship draught={{convert|11|m|ft|abbr=on}}
|Ship draft=
|Ship depth=
|Ship ice class=
|Ship power=* Two [[OK-150 reactor|OK-900A]] [[nuclear reactor]]s (2{{nbsp}}×{{nbsp}}171{{nbsp}}MW)
* Two steam turbogenerators (2{{nbsp}}×{{nbsp}}27.6{{nbsp}}MW)
|Ship propulsion=* Nuclear-turbo-electric
* Three shafts (3{{nbsp}}×{{nbsp}}18{{nbsp}}MW)
|Ship speed={{convert|20.6|kn}} (maximum)
|Ship range=
|Ship endurance=7.5 months
|Ship crew=189
|Ship aircraft=1 × [[Mil Mi-2|Mi-2]], [[Mil Mi-8|Mi-8]] or [[Kamov Ka-27|Ka-27]] helicopter
|Ship aircraft facilities=Helipad and hangar for one helicopter
|Ship notes=
}}
|}
The '''''Arktika'' class''' is a Russian (formerly [[Soviet Union|Soviet]]) class of [[nuclear-powered icebreaker]]s. Also known by their Russian designations '''Project 10520''' (first two ships) and '''Project 10521''' (from third ship onwards), they were the world's largest and most powerful icebreakers until the 2016 launch of the first [[Project 22220 icebreaker]], also named ''[[Arktika (2016 icebreaker)|Arktika]]''.<ref>{{cite news|title=Атомоход "50 лет Победы" готовится к выходу в Балтику|url=http://ria.ru/atomtec_news/20120118/542340638.html|newspaper=[[RIA Novosti]]|date=18 January 2012}}</ref><ref>{{Cite web|url=https://www.npr.org/sections/thetwo-way/2016/06/16/482288188/russia-launches-worlds-biggest-most-powerful-icebreaker|title = Russia Launches World's Biggest, Most Powerful Icebreaker|website = NPR|date = 16 June 2016|last1 = Domonoske|first1 = Camila}}</ref> 

Ships of the ''Arktika'' class are owned by the [[Government of Russia|federal government]], but were operated by the [[Murmansk Shipping Company]] (MSCO) until 2008, when they were transferred to the fully [[State corporation (Russia)|state-owned corporation]] [[Atomflot]]. Of the ten civilian nuclear-powered vessels{{Not verified in body|date=October 2022}}<!-- no source supports that "ten" is the correct and current number --> built by Russia or the [[Soviet Union]], six were of this type. 

They are used for escorting merchant ships in the [[Arctic Ocean]] north of [[Siberia]] as well as for scientific and recreational expeditions to the [[Arctic]].

==History==
[[File:Russian Nuclear Icebreaker Arktika.jpg|250px|thumb|right|''[[Arktika (1972 icebreaker)|Arktika]]'']]
[[File:50 Let Pobedy.jpg|250px|thumb|right|''[[50 Let Pobedy]]'']]
On July 3, 1971, construction began on a conceptual design of a larger nuclear icebreaker, dubbed ''[[Arktika (1972 icebreaker)|Arktika]]'', in the [[Baltic Shipyard]] in then [[St. Petersburg|Leningrad]].<ref name="Olagaard, P. Reistad 2006">Olagaard, P. Reistad, O. (April 2006). Russian Nuclear Power Plants for Marine Applications</ref> Four years later, on December 17, 1975, the first ship completed [[sea trials]].<ref name="globalsecurity">Pike, J. Project 10520 Arktika/ Global Security.Org. http://www.globalsecurity.org/military/world/russia/10520.htm</ref>

''Arktika'' was the first surface ship to reach the [[North Pole]], on August 17, 1977.{{cn|date=January 2025}}

As the leading vessel in Russia's second nuclear icebreaker class, ''Arktika'' became the classification name for five icebreakers to follow: the ''[[Sibir (1977 icebreaker)|Sibir]]'' in 1977, ''[[Rossiya (1983 icebreaker)|Rossiya]]'' in 1985, ''[[Sovetskiy Soyuz (icebreaker)|Sovetskiy Soyuz]]'' in 1989, the [[Yamal (icebreaker)|''Yamal'']] in 1992<ref>Hore-Lacy, I. World Nuclear Agency. (January 11, 2010). Nuclear Powered Ships/Encyclopedia of Earth.Org. {{cite web|url=http://www.eoearth.org/article/Nuclear-powered_ships |title=Nuclear-powered ships |access-date=2012-04-19 |url-status=dead |archive-url=https://web.archive.org/web/20121020010454/http://www.eoearth.org/article/Nuclear-powered_ships |archive-date=2012-10-20 }}</ref> and the ''[[50 Let Pobedy]]'' in 2007.

The first of new class of nuclear icebreakers, [[Project 22220 icebreaker|Project 22220]], was launched in 2016. Also called [[Arktika (2016 icebreaker)|''Arktika'']], it was launched in anticipation of decreasing ice{{why|date=January 2025}} and increased traffic.<ref>{{cite web|url=https://www.npr.org/sections/thetwo-way/2016/06/16/482288188/russia-launches-worlds-biggest-most-powerful-icebreaker|title=Russia Launches World's Biggest, Most Powerful Icebreaker|date=16 June 2016|work=NPR.org|access-date=21 June 2016}}</ref>

==Design and construction ==
===OK-900A reactors===
[[File:NSF picture of Yamal.jpg|250px|thumb|right|[[Yamal (icebreaker)|''Yamal'']]]]
Over the period December 1967 to May 1970, [[Lenin (1957 icebreaker)|''Lenin'']], precursor of the ''Arktika'' and the first nuclear-propelled icebreaker, had its three [[OK-150 reactor]]s, capable of 90 MW each, replaced with two OK-900 reactors, capable of 159 MW each.<ref name="Olagaard, P. Reistad 2006"/> The work was carried out at the Zvezdochka yard in [[Severodvinsk]].<ref>[http://www.bellona.org/english_import_area/international/russia/civilian_nuclear_vessels/icebreakers/30131 "Nuclear icebreaker Lenin"] {{webarchive |url=https://web.archive.org/web/20071015031630/http://www.bellona.org/english_import_area/international/russia/civilian_nuclear_vessels/icebreakers/30131 |date=October 15, 2007 }}, Bellona, 20/06/2003.</ref>

''Arktika'' and the entire ''Arktika''-class icebreaker fleet are outfitted with two OK-900A reactors, which deliver 171 MW each.{{inconsistent}}<!-- other places in the article: 159 MW --> Each reactor is contained in its own closed compartment and weighs 160 tonnes. They are shielded by water, steel, and high density concrete, and ambient radiation is monitored throughout the ship by 86 sensors.<ref name="globalsecurity" /> The reactors were originally fueled by a 90% enriched, zirconium-clad, [[uranium]] fuel. Those reactors still in operation today now use a 20%-90% enriched with 60% average enrichment uranium{{clarify|date=August 2013}} dispersed in an [[aluminum]] matrix.<ref>Bukharin, O. (2006), Russia's Nuclear Icebreaker Fleet. Taylor and Francis Group, LLC.</ref> The chain reaction can be stopped in 0.6 seconds by the full insertion of safety rods.<ref name="globalsecurity" />
 
''Arktika'' consumes up to 200&nbsp;grams of fuel a day when breaking ice. There are 500&nbsp;kg of [[uranium isotopes]] in each reactor, allowing for at least 13.7 years between changing reactor cores. The used cores are extracted and replaced in Murmansk, the spent fuel reprocessed and waste disposed of at a [[radioactive waste]] plant.<ref name="globalsecurity" />

===Propulsion===
The OK-900A is a [[pressurized water reactor]], meaning that cooling water is continually pumped under pressure through the reactor to remove heat, keeping the cores and the reactor cool. The heated water is pumped from the reactor to a [[boiler]] (four boilers per reactor), where it transfers its heat into another body of water, producing steam at a rate of 30&nbsp;kgf/cm<sup>2</sup> (2.94&nbsp;MPa, or approximately 1,084 psi). Each set of four boilers drives two [[steam turbine]]s, which turn three [[dynamo]]s. One kilovolt of [[direct current]] is then delivered to three double-wound motors directly connected to the [[propeller]], providing an average screw velocity of 120-180 rpm. Five auxiliary steam turbines are tied into the plant to provide electricity, turning generators with a cumulative electric power of 10 MW.<ref name="globalsecurity" />

Three fixed-pitch propellers provide ''Arktika'' with its thrust, power, and maneuverability. The starboard and centerline propellers turn clockwise while the port turns counter clockwise to compensate. Each propeller sits at the end of a 20-meter (65.6&nbsp;ft) shaft and has four blades, which weigh seven tons{{clarify | reason = Each, or in total?|date=August 2013}} and are attached by nine bolts to the hub which is 5.7 meters (18.7&nbsp;ft) in diameter and weighs 50 tonnes. ''Arktika'' also carries four spare blades along with the appropriate diving equipment and tools so that propeller repairs may be made at sea; the operation can take anywhere from one to four days depending on the extent of the damage.<ref name="globalsecurity" />

The propellers can deliver a combined [[bollard pull]] of 480 tons with 18-43 MW (25,000 shaft horsepower) [totals: 55.3 MW (75,000 shp)]. This amounts to a maximum speed of {{convert|22|kn}} on open water, full speed{{clarify|date=April 2013}} of {{convert|19|kn}}, and an average speed of {{convert|3|kn}} while icebreaking {{convert|2|-|3|m|ft|0}} thick level ice.<ref name="globalsecurity" />

==Ships==

{| class="wikitable"
|-
! Name
! Builder
! Laid down
! Launched
! Commissioned
! Status
|-style="background:#FFFFFF;" 
| {{ship||Arktika|1972 icebreaker|2}}
| [[Baltic Shipyard]]
| 3 July 1971
| 26 December 1972
| 25 April 1975
| Decommissioned in 2008, moored in [[Murmansk]]{{cn|date=October 2022}}
|-style="background:#FFFFFF;" 
| {{ship||Sibir|1977 icebreaker|2}}
| [[Baltic Shipyard]]
| 26 June 1974
| 23 February 1976
| 28 December 1977
| Decommissioned in 1992, moored in Murmansk{{cn|date=October 2022}}
|-style="background:#FFFFFF;" 
| {{ship||Rossiya|1983 icebreaker|2}}
| [[Baltic Shipyard]]
| 20 February 1981
| 2 November 1983
| 20 December 1985
| Decommissioned in 2013, laid up in Murmansk{{cn|date=October 2022}}
|-style="background:#FFFFFF;" 
| {{ship||Sovetskiy Soyuz|icebreaker|2}}
| [[Baltic Shipyard]]
| 2 November 1983
| 31 October 1986
| 29 December 1989
| Decommissioned in 2014, laid up in Murmansk 
|-
| {{ship||Yamal|icebreaker|2}}
| [[Baltic Shipyard]]
| 1986
| 1989
| October 1992
| In service
|-
| {{ship||50 Let Pobedy}}
| [[Baltic Shipyard]]
| 4 October 1989
| 29 December 1993
| 23 March 2007
| In service
|}

==See also==
*[[Taymyr (1987 icebreaker)]]
*[[Vaygach (1989 icebreaker)]]

==References==
{{Reflist}}

==External links==
* [http://www.bellona.org/subjects/1140451072.49 Nuclear Powered Icebreakers] {{Webarchive|url=https://web.archive.org/web/20130729083940/http://www.bellona.org/subjects/1140451072.49 |date=2013-07-29 }}, Bellona Foundation
* [https://web.archive.org/web/20080831093418/http://atomic.msco.ru/cgi-bin/common.cgi?lang=eng&skin=menu2&fn=technic Technical information], MSCO
* [https://web.archive.org/web/20120207093334/http://www.barentsobserver.com/russia-scraps-another-nuclear-powered-icebreaker.4523697.html Russia scraps another nuclear-powered icebreaker], Barents Observer
* [https://web.archive.org/web/20081219221245/http://www.coolantarctica.com/Antarctica%20fact%20file/ships/Yamal_ice_breaker.htm The Yamal, a nuclear powered Icebreaker page], Cool Antarctica

{{Polar exploration|state=collapsed}}
{{Nuclear-powered icebreakers}}

{{DEFAULTSORT:Arktika-class icebreaker}}
[[Category:Arktika-class icebreakers| ]]
[[Category:Soviet inventions]]
[[Category:Auxiliary icebreaker classes]]