''Mudyug'' () is a Russian

icebreaker An icebreaker is a special-purpose ship or boat designed to move and navigate through ice-covered waters, and provide safe waterways for other boats and ships. Although the term usually refers to ice-breaking ships, it may also refer to smaller ...

and the

lead ship The lead ship, name ship, or class leader is the first of a series or class of ships that are all constructed according to the same general design. The term is applicable to naval ships and large civilian vessels. Large ships are very comple ...

of a series of three

subarctic The subarctic zone is a region in the Northern Hemisphere immediately south of the true Arctic, north of hemiboreal regions and covering much of Alaska, Canada, Iceland, the north of Fennoscandia, Northwestern Russia, Siberia, and the Cair ...

icebreakers built at

Wärtsilä Wärtsilä Oyj Abp (), trading internationally as Wärtsilä Corporation, is a Finnish corporation, Finnish company which manufactures and services power sources and other equipment in the Marine propulsion, marine and energy markets. The core ...

Helsinki shipyard in Finland in 1982–1983. The vessel's non-rebuilt sister ships are ''Magadan'' and ''Dikson''. ''Mudyug'' was rebuilt with a new Thyssen-Waas icebreaking bow at

Nordseewerke Nordseewerke Emden GmbH (sometimes abbreviated NSWE, in English: North Sea Company) was a shipbuilding company, located in the Emden Harbor of the north German city of Emden. Founded in 1903, shipbuilding ended in 2010, and the company was taken ...

in 1986.

Design

''Mudyug'' was originally built with a

overall length The overall length (OAL) of an ammunition cartridge is a measurement from the base of the brass shell casing to the tip of the bullet, seated into the brass casing. Cartridge overall length, or "COL", is important to safe functioning of reloads i ...

of , or if the towing notch is included, and a maximum beam of . However, the 1986 conversion increased the vessel's hull length to and beam to at the widest point of the hull. When loaded to the maximum draught of , the icebreaker has a

displacement Displacement may refer to: Physical sciences Mathematics and physics *Displacement (geometry), is the difference between the final and initial position of a point trajectory (for instance, the center of mass of a moving object). The actual path ...

of , about 30% greater than that of the non-rebuilt sister ships. The vessel's

ice class Ice class refers to a notation assigned by a classification society or a national authority to denote the additional level of strengthening as well as other arrangements that enable a ship to navigate through sea ice. Some ice classes also have ...

, LL4, is intended for icebreaking operations primarily in ports and coastal areas. Unlike most icebreakers, ''Mudyug'' has a diesel-mechanical propulsion system where the vessel's four 8-cylinder

8R32 medium-speed main engines are coupled in pairs through Lohmann & Stolterfoht Navilus twin-input/single-output single-stage reduction gearboxes to propeller shafts driving four-bladed stainless steel KaMeWa

controllable pitch propeller Controllability is an important property of a control system and plays a crucial role in many regulation problems, such as the stabilization of unstable systems using feedback, tracking problems, obtaining optimal control strategies, or, simply p ...

s. In order to protect the main engines from large torque variations during icebreaking operations and to prevent the propellers from stopping when the blades come in contact with ice, each shaft has a

flywheel A flywheel is a mechanical device that uses the conservation of angular momentum to store rotational energy, a form of kinetic energy proportional to the product of its moment of inertia and the square of its rotational speed. In particular, a ...

to increase

rotational inertia The moment of inertia, otherwise known as the mass moment of inertia, angular/rotational mass, second moment of mass, or most accurately, rotational inertia, of a rigid body is defined relatively to a rotational axis. It is the ratio between ...

of the drivetrain. Onboard electrical power is generated by three Wärtsilä-Vasa 624TS auxiliary diesel engines with 960 kVA alternators. ''Mudyug''s icebreaking capability is further increased by a hull lubrication system and an active heeling system. During the 1986 conversion, the original Wärtsilä Air Bubbling System (WABS) was replaced with a Jastram-HSVA water deluge system. ''Mudyug''s

bollard pull Bollard pull is a conventional measure of the pulling (or towing) power of a watercraft. It is defined as the force (usually in tonnes-force or kilonewtons (kN)) exerted by a vessel under full power, on a shore-mounted bollard through a tow-line, ...

is when operating with a continuous propulsion power of . However, for short-term operation the icebreaker can use its maximum shaft output of to generate a bollard pull of . The vessel has a service speed of in open water and, prior to rebuilding its icebreaking bow, could maintain a continuous speed of when breaking thick level ice.

History

Development and construction

In 1977, Wärtsilä began developing a new

concept in close co-operation with experts from the

Soviet Union The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ...

. Although the Finnish shipbuilder had delivered more icebreaking vessels than any other shipyard in the world, they had all been diesel-electric vessels where

diesel generator A diesel generator (DG) (also known as a diesel genset) is the combination of a diesel engine with an electric generator (often an alternator) to generate electrical energy. This is a specific case of an engine generator. A diesel compress ...

s powered electric propulsion motors driving fixed-pitch propellers. In the new icebreakers, this fairly expensive specialized drivetrain would be replaced with cheaper and more efficient mechanical transmission where the main diesel engines would be connected to

s through a reduction gearbox. An extensive research program was initiated by Wärtsilä Arctic Design and Marketing (WADAM) to ensure that the new concept was viable and that the problems encountered the recently commissioned

United States Coast Guard The United States Coast Guard (USCG) is the maritime security, search and rescue, and Admiralty law, law enforcement military branch, service branch of the armed forces of the United States. It is one of the country's eight Uniformed services ...

Polar-class icebreaker Polar-class icebreakers , are heavy icebreakers operated by the United States Coast Guard (USCG). These cutters, specifically designed for icebreaking, have reinforced hulls, special icebreaking bows, and a system that allows rapid shifting of ...

s would be avoided. In April 1980, Wärtsilä and the Soviet Union signed a

FIM FIM may refer to: Organizations and companies * Fédération Internationale de Motocyclisme, the International Motorcycling Federation * Flint Institute of Music, in Michigan, United States * Fox Interactive Media, now News Corp. Digital Media * ...

400 million shipbuilding contract for the construction of three icebreakers to escort ships in the freezing

ports. The vessels, first of which would be delivered in late 1982 and the two following ones in 1983, would be stationed in the

Barents Sea The Barents Sea ( , also ; , ; ) is a marginal sea of the Arctic Ocean, located off the northern coasts of Norway and Russia and divided between Norwegian and Russian territorial waters.World Wildlife Fund, 2008. It was known earlier among Russi ...

Sea of Okhotsk The Sea of Okhotsk; Historically also known as , or as ; ) is a marginal sea of the western Pacific Ocean. It is located between Russia's Kamchatka Peninsula on the east, the Kuril Islands on the southeast, Japan's island of Hokkaido on the sou ...

and

Baltic Sea The Baltic Sea is an arm of the Atlantic Ocean that is enclosed by the countries of Denmark, Estonia, Finland, Germany, Latvia, Lithuania, Poland, Russia, Sweden, and the North European Plain, North and Central European Plain regions. It is the ...

. The

, ''Mudyug'', was

laid down Laying the keel or laying down is the formal recognition of the start of a ship's construction. It is often marked with a ceremony attended by dignitaries from the shipbuilding company and the ultimate owners of the ship. Keel laying is one ...

Hietalahti shipyard Hietalahti shipyard (also known as Helsinki New Shipyard, ) is a shipyard in Hietalahti, in downtown Helsinki, Finland. Since 2019, it has been operated by a company named Helsinki Shipyard. History The shipyard, first known as Helsingfors ...

on 30 December 1980 and launched together with the second icebreaker of the series, ''Magadan'', on 16 April 1982. Shortely before the delivery of the vessel on 29 October 1982, ''Mudyug''s engine room accidentally flooded with water at quayside due to a faulty seacock.

1986 rebuilding

In October 1986, ''Mudyug'' was retrofitted with new bow with the intention of improving the vessel's icebreaking capability by a factor of 1.5 without increasing its propulsion power. The icebreaker's traditional wedge-shaped bow was replaced with a so-called Thyssen-Waas bow developed by Thyssen Nordseewerke in cooperation with the Hamburg Ship Model Basin (Hamburgische Schiffbau-Versuchsanstalt; HSVA). The pontoon-shaped bow, which broke ice by shearing instead of traditional bending, had been previously tested in the early 1980s on the German icebreaker ''Max Waldeck''. While initial ice trials in

Svalbard Svalbard ( , ), previously known as Spitsbergen or Spitzbergen, is a Norway, Norwegian archipelago that lies at the convergence of the Arctic Ocean with the Atlantic Ocean. North of continental Europe, mainland Europe, it lies about midway be ...

demonstrated that the new bow had improved ''Mudyug''s icebreaking capability significantly, the barge-like bow worked well only in unbroken level ice. In broken ice and rubble on shipping lanes, it had a tendency of pushing the ice in front of the vessel. Due to these limitations, ''Mudyug'' was eventually considered unsuitable for icebreaking in the Arctic seas and transferred to the Baltic Sea in the late 1990s.

Career

''Mudyug'' was delivered to the Northern Shipping Company in 1982 and was deployed to escort ships to and from

Arkhangelsk Arkhangelsk (, ) is a types of inhabited localities in Russia, city and the administrative center of Arkhangelsk Oblast, Russia. It lies on both banks of the Northern Dvina near its mouth into the White Sea. The city spreads for over along the ...

in the

White Sea The White Sea (; Karelian language, Karelian and ; ) is a southern inlet of the Barents Sea located on the northwest coast of Russia. It is surrounded by Karelia to the west, the Kola Peninsula to the north, and the Kanin Peninsula to the nort ...

. In July 2006, the icebreaker was transferred to Rosmorport and its homeport changed to

Saint Petersburg Saint Petersburg, formerly known as Petrograd and later Leningrad, is the List of cities and towns in Russia by population, second-largest city in Russia after Moscow. It is situated on the Neva, River Neva, at the head of the Gulf of Finland ...

where the vessel had already operated since the late 1990s. , ''Mudyug'' remains in service in the

Gulf of Finland The Gulf of Finland (; ; ; ) is the easternmost arm of the Baltic Sea. It extends between Finland to the north and Estonia to the south, to Saint Petersburg—the second largest city of Russia—to the east, where the river Neva drains into it. ...

Notable events

On 17 November 2013, ''Mudyug''s lifeboat was destroyed when a strong gust of wind pushed the passenger ferry ''Princess Maria'' against the docked icebreaker. There were no injuries onboard either vessel and the ferry docked safely at the passenger terminal after the collision. On 25 January 2018, bulk carrier ''S-Bronco'' collided with ''Mudyug'' outside Saint Petersburg. While the merchant ship suffered superficial damage above waterline, there was no visible damage on the icebreaker. ''Mudyug'' has regularly participated in the annual Festival of Icebreakers in Saint Petersburg. The icebreaker has been open to visitors in four consecutive years between 2016 and 2019.

References

{{reflist Icebreakers of Russia Icebreakers of the Soviet Union Ships built in Helsinki 1982 ships