Nuclear powered icebreaker

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Nuclear icebreaker Yamal on its way to the North Pole in August 2001

A nuclear powered icebreaker is a purpose-built ship for use in waters continuously covered with ice. Icebreakers are ships capable of cruising on ice-covered water by breaking through the ice with their strong, heavy, steel bows. Nuclear powered icebreakers are far more powerful than their diesel powered counterparts, and have been constructed by Russia primarily to aid shipping in the frozen Arctic waterways in the north of Siberia.

During the winter, the ice along the northern seaways varies in thickness from 1.2 to 2.0 metres (3.9 to 6.5 feet). The ice in central parts of the Arctic Ocean is on average 2.5 metres (8.2 ft) thick. Nuclear-powered icebreakers can force through this ice at speeds up to 10 knots (19 km/h). In ice-free waters the maximum speed of the nuclear-powered icebreakers is as much as 21 knots (35 km/h).

1 Uses of nuclear-powered icebreakers
2 Russian nuclear icebreakers
3 Arctic tourism
4 See also
5 References
6 External links

[edit] Uses of nuclear-powered icebreakers

The nuclear ice breakers of the Arktika (Arctic) design are used to force through the ice for the benefit of cargo ships and other vessels along the northern seaway. The northern seaway comprises the eastern part of the Barents Sea, the Petchora Sea, the Kara Sea, the Laptev Sea and the Eastern Siberia Sea to the Bering Strait. Important ports on the northern seaway are, among others, Dikson, Tiksi, and Pevek.

Two nuclear-powered icebreakers, NS Vaigach and NS Taimyr, have been built for shallow waters and are usually used on the river Yenisei to Dikson, where they break through the ice followed by cargo ships with lumber from Igarka and cargo ships with ore and metals from the Norilsk Company's port Dudinka. These nuclear powered icebreakers can also be used as fireboats.

The icebreakers have also been used for a number of scientific expeditions in the Arctic. On August 17, 1977, the NS Arktika was the first surface vessel in the world to reach the North Pole. Since 1989, some icebreakers have been used for Arctic tourism cruises.

[edit] Russian nuclear icebreakers

In all, ten civilian nuclear powered vessels have been built in Russia. Nine of these are icebreakers, and one is a container ship with an ice-breaking bow. All nuclear-powered icebreakers of the NS Arktika design have been built at the Admiralty Shipyard in St. Petersburg. The NS Vaigach and NS Taimyr were built at the Helsinki New Shipyard in Finland and then brought to Russia for installation of the reactors and steam propulsion systems.

Ship Name	Launched	Project Number	Type	Class	Comments
NS Lenin	1959	92M	Icebreaker	Lenin	Decommissioned 1989. Museum ship.
NS Arktika	1975	1052-1	Icebreaker	Arktika	Not operational.
NS Sibir	1977	1052-2	Icebreaker	Arktika	Defueled and not operational since 1993.
NS Rossiya	1985	10521-1	Icebreaker	Arktika
NS Sevmorput	1988	10081	Container ship	Sevmorput	Has ice-breaking bow
NS Taimyr	1989	10580-1	River Icebreaker	Taimyr
NS Sovetskiy Soyuz	1990	10521-2	Icebreaker	Arktika
NS Vaigach	1990	10580-2	River Icebreaker	Taimyr
NS Yamal	1993	10521-3	Icebreaker	Arktika
NS 50 Let Pobedy	1993	10521	Icebreaker	Arktika	Built as NS Ural, completed in 2007.

[edit] Lenin class

Main article: Soviet icebreaker Lenin

At its launch in 1957 the icebreaker NS Lenin was both the world's first nuclear powered surface ship and the first nuclear powered civilian vessel. Lenin was put into ordinary operation in 1959. Lenin had two nuclear accidents, the first in 1965, and the second in 1967. The second accident resulted in one of the three OK-150 reactors being damaged beyond repair. All three reactors were removed, and replaced by two OK-900 reactors; the ship returned to service in 1970. The Lenin was taken out of operation in November 1989 and laid up at Atomflot, the base for nuclear powered icebreakers, in the Murmansk Fjord. Conversion to a museum ship was scheduled to be completed during 2005.

[edit] Arktika class

Arktika class icebreakers are the bulk of the Russian nuclear icebreaker fleet; six of Russia's ten nuclear civilian ships are Arktikas. Since they have been built over a period of thirty years, there is a fair bit of variation between ships of the class; thus specifications are listed as a range of values. In general, the newer ships are larger, faster, and require smaller crews.

Specifications:

Length: 148 m to 159 m (approximately 136 m at the waterline)
Beam: 30 m (28 m at the waterline)
Draft: approximately 11.08 m.
Height (keel to masthead): approximately 55 m
Displacement: 23,000 to 25,000 tons
Maximum speed: 18 to 22 knots
Cruising speed: approximately 18 to 20 knots
Crew: 138 to over 200
Passengers: approximately 100
Reactors: 2 OK-900A, 171 megawatt each
Propulsion: 3 propellers totalling approximately 75,000 hp
Maximum Ice Thickness: 2 to 2.8 m
Endurance: 7.5 months at sea, 4 years between refuelings

Arktika-class icebreakers have a double hull, with the outer hull being approximately 48 mm thick at the ice-breaking areas and 25 mm thick elsewhere. There is water ballast between the inner and outer hulls which can be shifted to aid icebreaking. Icebreaking is also assisted by an air bubbling system which can deliver 24 m³/s of water from jets 9 m below the surface. Some ships have polymer coated hulls to reduce friction. Arktika-class ships can break ice while making way either forwards or backwards. These ships must cruise in cold water, in order to cool their reactors. As a result, they cannot pass through the tropics to undertake voyages in the Southern hemisphere. Although they have two reactors, normally only one is used to provide power, with the other being maintained in a standby mode.

Some ships carry one or two helicopters and several Zodiac boats. Radio and satellite systems can include navigation, telephone, fax, and email capabilities.

Most nuclear powered icebreakers in the Russian service today have a swimming pool, a sauna, a cinema, and a gymnasium. In the restaurants aboard there is a bar and facilities for live music performances. Some also have a library and at least one has a volleyball court.

[edit] Individual Ships

On 1977-08-17, the NS Arktika ("Arctic") became the first surface ship ever to reach the North Pole.

The NS Arktika and NS Sibir ("Siberia") are presently not in operation but are stationed at Atomflot for extensive repair. Among other things, the nuclear reactors and turbine generators are to be upgraded as these do not satisfy the safety standards established for newer nuclear powered icebreakers. The Arktika's reactors have operated for over 150,000 hours, and research is underway to determine if they can be refitted to yield another 25,000 to 50,000 hours of service.

Neither the NS Arktika, nor the NS Sibir might ever come into operation again due to the operational economics. Unless there is a significant increase of transport in the Arctic it will not be profitable to operate all six Arktika-class icebreakers. It is to be expected that the oldest icebreakers would be the first ones to be taken out of operation.

The NS Rossiya ("Russia") carries two helicopters. Rossiya was used to transport an expedition of around 40 West Germans to the North Pole in the Summer of 1990; this may have been the first non-communist charter of a nuclear icebreaker. Rossiya was in refit as of December 2004.

The NS Sovetskiy Soyuz was trapped in ice for three days in 1998. In 2004, it was one of three icebreakers used for an Arctic ice core expedition intended to research climate change and global warming. One tourism operator lists it as being possibly used for North Pole cruises.

The NS Yamal is mostly used for tourism and scientific expeditions. It has 50 passenger cabins and suites, and carries one helicopter. The crew is 150, including 50 officers and engineers. Yamal was the 12th surface ship ever to reach the North Pole.

The NS 50 Let Pobedy ("50 Years Since Victory") is the final Arktika class ship. It was launched from the shipyard at Saint Petersburg on December 29, 1993 as the NS Ural, and delivered to Murmansk in 1994. It was later renamed and not actually completed and commissioned until 2006 due to funding delays. The crew is expected to normally number 138 persons. It has an environmental waste processing module added to the hull which accounts for 9 m of the ship's 159 m length; this makes it the largest of the Arktika class and the largest nuclear powered icebreaker in the world. It carries two Ka-32 helicopters. It entered service on April 2, 2007.

[edit] Taimyr class

Taimyr is also sometimes spelled Taymyr in English, and Vaiguch is sometimes spelled Vayguch. The ships were built at the Helsinki New Shipyard in Finland by Wärtsilä. The nuclear reactors were installed at the Leningrad Baltic Shipyard in the Soviet Union after delivery from Finland.^[1]

Taimyr class specifications:

Length: 150.2 m (Taimyr), 151.8 m (Vaiguch)
Beam: 29.2 m
Draft: 8.0 m
Height: 15.2 m keel to main deck, 8 stories from main deck to bridge
Displacement: 20,000 tons
Speed: 18.5 knots
Crew: 120 to 138
Reactors: One KLT-40M reactor producing 135 MW
Propulsion: 3 propellers totalling 52,000 hp

The bow hull plating is approximately 32 mm thick. As of December 2004, both vessels were undergoing refitting.

[edit] Infrastructure

Support facilities include the fuel transports Imandra and Lotta which are used for refuelling and spent fuel. The Volodarsky is used for storage of solid waste; it can hold 300 cubic meters. Serebryanka is a tanker used for liquid waste which can hold 1000 cubic meters of material. The Rosta-1 boat is used for radiation monitoring and control, including sanitization of workers.

A third fuel vessel, Lepse, is filled with spent nuclear fuel elements, many of them damaged and thus difficult to handle. In addition to the materials on board, the ship itself is heavily contaminated. It forms one of the world's most difficult and potentially dangerous nuclear waste disposal problems; an accident there could release more radiation then the Chernobyl catastrophe into the immediate vicinity of Murmansk. A small crew monitors the ship on a constant basis while Russia tries to raise the money and perform the research needed for safe disposal.

In all, about 2,000 people work aboard the icebreakers, the nuclear powered container ship, and aboard the service and storage ships stationed at the Atomflot harbour. The crew on the civil nuclear powered vessels receive special training at the Makarov college in St. Petersburg, Russia.

Icebreakers generally try to navigate paths with the least possible ice in order to make speedier progress and to help ensure that they do not become trapped in ice too thick for them to break. In the 1970s and 1980s, land-based aircraft would observe and map the ice to help with course plotting. Over time, most of this work has been taken over by satellite surveillance systems, sometimes aided by the helicopters carried by the icebreakers.

[edit] Arctic tourism

"Yamal", August 2001

Since 1989 the nuclear powered icebreakers have also been used for tourist purposes carrying passengers to the North Pole. Each participant pays up to US$ 25,000 for cruises lasting three weeks. The NS Sibir was used for the first two tourist cruises in 1989 and 1990. In 1991 and 1992, the tourist trips to the North Pole were undertaken by NS Sovyetski Soyuz. During the summer of 1993 the NS Yamal was used for three tourist expeditions in the Arctic. The NS Yamal has a separate accommodation section for tourists. The NS 50 Let Pobedy contains an accommodation deck customised for tourists.