Misplaced Pages

#64935

102-458: Katajanokka Casino is a restaurant and function venue in the Katajanokka neighbourhood of Helsinki . The building is located upon a promontory on the north side of the island next to the marina. It is not a casino in the sense of a gambling establishment. Designed by the architect A. Nyberg and completed in 1913, it was created for the use of Russian imperial officers during the period of

204-625: A 1775 map, while the Finnish name Katajanokka was first mentioned in the Suometar newspaper in 1856. From the 1810s to the 1830s barracks buildings designed by Carl Ludvig Engel and Anders Fredrik Granstedt for the use of the Russian military were built on the eastern tip of Katajanokka. In 1831 the barracks were taken into use by the First marine crew of Finland , which also caused the name of

306-536: A architecture design competition held in 2001. The building would have been located next to the Stora Enso main office, in place of the Kanavaterminaali building. No funding could be found for the project and the organisations behind it parted ways, so the project was finally abandoned in 2006. In 2007 there was a plan for a hotel at the same site, named after Alvar Aalto and riding on his reputation, with

408-586: A cargo ship. One of the cranes was unloading cargo from the SS Niobe when a chain of cargo carriages crashed into one of the crane's legs at a spot where the crane tracks and the railway tracks crossed. The crane fell down and was completely destroyed, but its driver suffered no injuries. The last four harbour cranes in Katajanokka were dismantled in January 1986. Guarding the harbour area in Katajanokka

510-582: A combined propulsion power of 34,000 kW (46,000 hp). In Canada, diesel-electric icebreakers started to be built in 1952, first with HMCS Labrador (was transferred later to the Canadian Coast Guard), using the USCG Wind -class design but without the bow propeller. Then in 1960, the next step in the Canadian development of large icebreakers came when CCGS  John A. Macdonald

612-625: A heavy icebreaker must perform Operation Deep Freeze , clearing a safe path for resupply ships to the National Science Foundation ’s facility McMurdo in Antarctica. The most recent multi-month excursion was led by the Polar Star which escorted a container and fuel ship through treacherous conditions before maintaining the channel free of ice. Icebreakers are often described as ships that drive their sloping bows onto

714-535: A hull that is wider in the bow than in the stern. These so-called "reamers" increase the width of the ice channel and thus reduce frictional resistance in the aftship as well as improve the ship's maneuverability in ice. In addition to low friction paint, some icebreakers utilize an explosion-welded abrasion-resistant stainless steel ice belt that further reduces friction and protects the ship's hull from corrosion. Auxiliary systems such as powerful water deluges and air bubbling systems are used to reduce friction by forming

816-440: A long time, the image of the northern shore of Katajanokka was dominated by large warehouses belonging to a freight forwarder . These have later been renovated into the use of restaurants and cafés. The northern shore used to also host a garbage pier, where excrement was loaded into barges which took it to the countryside to act as fertiliser for the country fields. However, sometimes garbage transporters dumped their cargo right into

918-524: A lubricating layer between the hull and the ice. Pumping water between tanks on both sides of the vessel results in continuous rolling that reduces friction and makes progress through the ice easier. Experimental bow designs such as the flat Thyssen-Waas bow and a cylindrical bow have been tried over the years to further reduce the ice resistance and create an ice-free channel. Icebreakers and other ships operating in ice-filled waters require additional structural strengthening against various loads resulting from

1020-417: A nuclear-powered icebreaking cargo ship, Sevmorput , which had a single nuclear reactor and a steam turbine directly coupled to the propeller shaft. Russia, which remains the sole operator of nuclear-powered icebreakers, is currently building 60,000 kW (80,000 hp) icebreakers to replace the aging Arktika class. The first vessel of this type entered service in 2020. A hovercraft can break ice by

1122-451: A ship to be considered an icebreaker, it requires three traits most normal ships lack: a strengthened hull , an ice-clearing shape, and the power to push through sea ice . Icebreakers clear paths by pushing straight into frozen-over water or pack ice . The bending strength of sea ice is low enough that the ice breaks usually without noticeable change in the vessel's trim . In cases of very thick ice, an icebreaker can drive its bow onto

SECTION 10

#1732790152065

1224-518: A short parallel midship to improve maneuverability in ice. However, the spoon-shaped bow and round hull have poor hydrodynamic efficiency and seakeeping characteristics, and make the icebreaker susceptible to slamming , or the impacting of the bottom structure of the ship onto the sea surface. For this reason, the hull of an icebreaker is often a compromise between minimum ice resistance, maneuverability in ice, low hydrodynamic resistance, and adequate open water characteristics. Some icebreakers have

1326-607: A small canal was dug across the base of the headland in the 19th century. There are four bridges across the canal connecting Katajanokka with mainland Helsinki. Buildings in Katajanokka include the former Katajanokka prison (now a Tribute Portfolio hotel by Marriott), the Uspenski Cathedral , the Katajanokka Casino , Wanha Satama , the Stora Enso head office designed by Alvar Aalto , the building of

1428-641: A vertical axis. These thrusters improve propulsion efficiency, icebreaking capability and maneuverability of the vessel. The use of azimuth thrusters also allows a ship to move astern in ice without losing manoeuvrability. This has led to the development of double acting ships , vessels with the stern shaped like an icebreaker's bow and the bow designed for open water performance. In this way, the ship remains economical to operate in open water without compromising its ability to operate in difficult ice conditions. Azimuth thrusters have also made it possible to develop new experimental icebreakers that operate sideways to open

1530-593: A wide channel through ice. The steam-powered icebreakers were resurrected in the late 1950s when the Soviet Union commissioned the first nuclear-powered icebreaker , Lenin , in 1959. It had a nuclear-turbo-electric powertrain in which the nuclear reactor was used to produce steam for turbogenerators , which in turn produced electricity for propulsion motors. Starting from 1975, the Russians commissioned six Arktika -class nuclear icebreakers . Soviets also built

1632-676: A year, started being settled. The mixed ethnic group of the Karelians and the Russians in the North-Russia that lived on the shores of the Arctic Ocean became known as Pomors ("seaside settlers"). Gradually they developed a special type of small one- or two-mast wooden sailing ships , used for voyages in the ice conditions of the Arctic seas and later on Siberian rivers. These earliest icebreakers were called kochi . The koch's hull

1734-457: Is a neighbourhood of Helsinki , Finland , with around 4000 inhabitants in 2005. The district is located adjacent to the immediate downtown area, though in the first major town plan for Helsinki from the mid-18th century, the area fell outside the fortifications planned to encircle the city. Originally, Katajanokka was a headland of the Helsinki peninsula but is now technically an island, as

1836-464: Is caused by the force of winds and tides on ice formations. The first boats to be used in the polar waters were those of the Eskimos . Their kayaks are small human-powered boats with a covered deck, and one or more cockpits, each seating one paddler who strokes a single or double-bladed paddle . Such boats have no icebreaking capabilities, but they are light and well fit to carry over the ice. In

1938-575: Is considered an exceptional example of modern town planning . A major part of the project was the conversion and extension of the old Russian naval barracks to house the Finnish foreign ministry. The northern shore of Katajanokka still serves as a base for the Finnish coast guard, Helsinki maritime police as well as the Finnish icebreaker fleet. Landmarks of Katajanokka include the Russian Orthodox Cathedral, also known as Uspenski Cathedral (architect Alexey Gornostaev , 1868),

2040-418: Is frequented by large cruiseferries traveling between Helsinki, Stockholm , Mariehamn , Tallinn and Rostock . The rest of the district comprises co-operative apartment buildings and several small parks. The western part of the residential area, known as the "Old Side" of Katajanokka, is an upscale neighborhood and a well-preserved example of early 20th century Art Nouveau architecture, though up until

2142-460: Is in effect in Finland. Thus, as a hotel, the exterior of the building has been preserved, as has the central corridor of the old prison and even the old prison wall. A restaurant at the lowest level of the hotel has attempted to keep much of the character of the old prison alive. However, an actual former prisoner told a Finnish newspaper that the supposed "prison cutlery" is very different from what

SECTION 20

#1732790152065

2244-660: Is now the Senate Square to Katajanokka already in the 18th century. The outskirts settlements formed on the peninsula remained mostly untouched for decades even after the rest of Helsinki had been completely rebuilt according to the zoning plan made by Johan Albrecht Ehrenström in the early 19th century. The Katajanokka canal separating Katajanokka from the mainland and connecting the South and North Harbours of Helsinki with each other, already proposed in Ehrenström's plan,

2346-611: Is principally known for its fine examples of Jugendstil architecture. Other prominent styles apparent on the island are modernism , manifested in Alvar Aalto 's Enso-Gutzeit Building, and the red-brick industrial former harbour buildings and prison (now a Best Western hotel). Results of the 2011 Finnish parliamentary election in Katajanokka: 60°10′01″N 024°58′06″E  /  60.16694°N 24.96833°E  / 60.16694; 24.96833 Icebreaker For

2448-451: Is to perform model tests in an ice tank . Regardless of the method, the actual performance of new icebreakers is verified in full scale ice trials once the ship has been built. In order to minimize the icebreaking forces, the hull lines of an icebreaker are usually designed so that the flare at the waterline is as small as possible. As a result, icebreaking ships are characterized by a sloping or rounded stem as well as sloping sides and

2550-672: The Baltic Sea , the Great Lakes and the Saint Lawrence Seaway , and along the Northern Sea Route , the main function of icebreakers is to escort convoys of one or more ships safely through ice-filled waters. When a ship becomes immobilized by ice, the icebreaker has to free it by breaking the ice surrounding the ship and, if necessary, open a safe passage through the ice field. In difficult ice conditions,

2652-922: The Grand Duchy . The building was seized by revolutionary forces in 1917 and, since Finnish independence , the place has become a favourite venue for various Finnish military organizations. During the time of Russian Revolution before the World War I, 15 Russian soldiers were shot in front of the Casino building. Since World War II, the building has gone through various repairs and restorations. In its present state, Katajanokka Casino very much resembles its original fin-de-siècle style and appearance. 60°10′9.35″N 024°57′55.01″E  /  60.1692639°N 24.9652806°E  / 60.1692639; 24.9652806 Katajanokka Katajanokka ( Finnish: [ˈkɑtɑjɑˌnokːɑ] ; Swedish : Skatudden )

2754-589: The Ministry for Foreign Affairs and the Katajanokka Terminal used by Viking Line . Katajanokka is one of the most distinguished neighbourhoods in Helsinki. Katajanokka's residents have included former Finnish President (from 1982 to 1994) Mauno Koivisto , composer Einojuhani Rautavaara and author-artist Tove Jansson . The south side of Katajanokka is dominated by a passenger harbour which

2856-529: The St. Lawrence River . Icebreakers were built in order to maintain the river free of ice jam, east of Montréal . In about the same time, Canada had to fill its obligations in the Canadian Arctic. Large steam icebreakers, like the 80-metre (260 ft) CGS  N.B. McLean (1930) and CGS  D'Iberville (1952), were built for this dual use (St. Lawrence flood prevention and Arctic replenishment). At

2958-523: The Swiss architecture bureau Herzog & de Meuron invited to design it. In 2006 there was a plan to build a bridge from Katajanokka to Laajasalo . The bridge would have been taken into use for trams and pedestrian traffic. In later versions the bridge was replaced with a tunnel, and a line going via Tervasaari and Sompasaari was found as an alternative route. Later, the Crown Bridges project

3060-526: The United States Coast Guard , have a combined diesel-electric and mechanical propulsion system that consists of six diesel engines and three gas turbines . While the diesel engines are coupled to generators that produce power for three propulsion motors, the gas turbines are directly coupled to the propeller shafts driving controllable pitch propellers. The diesel-electric power plant can produce up to 13,000 kW (18,000 hp) while

3162-585: The VR warehouses south of the Töölönlahti bay along the city's coastline to the Katajanokka harbour, was built in 1894. The harbour was later changed into a passenger traffic harbour. Rail transport to the South Harbour and Katajanokka ended on 30 April 1980. Traffic on the cargo harbour rail decreased as the South Harbour became mostly a harbour for car ferries. Car ferry traffic started on 9 July 1974 by

Katajanokka Casino - Misplaced Pages Continue

3264-535: The Wind class . Research in Scandinavia and the Soviet Union led to a design that had a very strongly built short and wide hull, with a cut away forefoot and a rounded bottom. Powerful diesel-electric machinery drove two stern and one auxiliary bow propeller. These features would become the standard for postwar icebreakers until the 1980s. Since the mid-1970s, the most powerful diesel-electric icebreakers have been

3366-602: The "old side" of Katajanokka, was mostly built during one decade in the early 20th century. The buildings in the area form a rare harmonious Art Nouveau architectural entity. For example the architects Gesellius, Lindgren, Saarinen designed three of the houses: the first to be completed was the Tallberg house , whose design was the trio's first competition victory. Rebuilding of a couple of houses destroyed in World War II or unbuilt lots has been done in accordance with

3468-531: The 1920s of various buildings related to warehouse, workshop and dock activities. The Katajanokka Airport used by Aero Oy (now known as Finnair ) was also located on the southern shore of the area, serving as an airport for route flights from 1924 to 1936. When the navy garrison and the military harbour had moved to Upinniemi and the Valmet dock had moved to Vuosaari , most of the old warehouse and industrial buildings were dismantled. The zoning plan designed by

3570-529: The 2000s, International Association of Classification Societies (IACS) has proposed adopting an unified system known as the Polar Class (PC) to replace classification society specific ice class notations. Since the Second World War , most icebreakers have been built with diesel-electric propulsion in which diesel engines coupled to generators produce electricity for propulsion motors that turn

3672-703: The 9th and 10th centuries, the Viking expansion reached the North Atlantic , and eventually Greenland and Svalbard in the Arctic. Vikings , however, operated their ships in the waters that were ice-free for most of the year, in the conditions of the Medieval Warm Period . In the 11th century, in North Russia the coasts of the White Sea , named so for being ice-covered for over half of

3774-495: The Finnish military in the 1980s, the building survived, with various uses, mainly as a cultural centre. In the late 1990s, the city of Helsinki announced that it was going to demolish the building to build a new apartment building in its place. This caused huge protests, and the demolition was put off for almost a decade, mainly because of opposition from local inhabitants, and the Green League party. The navy school building

3876-593: The Market Square milieu and the cityscape dominated by the Uspenski Cathedral. When a white office building for the use of the development assistance department of the Ministry of Foreign Affairs was built near Aalto's building in 1993, the buildings have been seen as supporting each other and forming their own clear-bordered architectural entity. In 1913 the so-called Chapel of Peace was built at

3978-566: The Merikasarmi complex of the Foreign Ministry (architect Carl Ludvig Engel , 1825) and the Finnish headquarters of Stora Enso (architect Alvar Aalto , 1962; the most controversial of Aalto's works). Another famous building in Katajanokka is the former district prison of Southern Finland. The old prison dates back to 1837, and functioned as a prison until 2002. The prison underwent an extensive interior renovation to convert

4080-447: The Soviet Union. Two shallow-draft Taymyr -class nuclear icebreakers were built in Finland for the Soviet Union in the late 1980s. In May 2007, sea trials were completed for the nuclear-powered Russian icebreaker NS 50 Let Pobedy . The vessel was put into service by Murmansk Shipping Company, which manages all eight Russian state-owned nuclear icebreakers. The keel was originally laid in 1989 by Baltic Works of Leningrad , and

4182-483: The ability of an icebreaker to propel itself onto the ice, break it, and clear the debris from its path successfully is essential for its safety. Prior to ocean-going ships, ice breaking technology was developed on inland canals and rivers using laborers with axes and hooks. The first recorded primitive icebreaker ship was a barge used by the Belgian town of Bruges in 1383 to help clear the town moat. The efforts of

Katajanokka Casino - Misplaced Pages Continue

4284-596: The altered bow Pilot ' s design from Britnev to make his own icebreaker, Eisbrecher I . The first true modern sea-going icebreaker was built at the turn of the 20th century. Icebreaker Yermak , was built in 1899 at the Armstrong Whitworth naval yard in England under contract from the Imperial Russian Navy . The ship borrowed the main principles from Pilot and applied them to

4386-447: The architectural trio Vilhelm Helander , Pekka Pakkala and Mikael Sundman was confirmed in 1977 and from 1977 to 1986 a total of 21 new apartment buildings were built in the area. The last of the free lots were built from 2006 to 2009. The zoning plan sought to return to the tightly-built urban space in a contrast to the earlier suburban type of construction, which has later been seen as a turning point in Finnish city design. The plan

4488-589: The barracks to be established as Merikasarmi ("Marine barracks") instead of the Katajanokka barracks. This branch of the military was disestablished in the 1880s when the Grand Duchy of Finland introduced conscription . After this, the area became the base of the Russian Baltic fleet. After Finland became independent the garrison moved to the Finnish Defence Forces . It hosted the Helsinki navy station and military station (until 1958),

4590-602: The beginning of the 20th century, several other countries began to operate purpose-built icebreakers. Most were coastal icebreakers, but Canada, Russia, and later, the Soviet Union , also built several oceangoing icebreakers up to 11,000 tons in displacement. Before the first diesel-electric icebreakers were built in the 1930s, icebreakers were either coal- or oil-fired steam ships . Reciprocating steam engines were preferred in icebreakers due to their reliability, robustness, good torque characteristics, and ability to reverse

4692-567: The bow altered to achieve an ice-clearing capability (20° raise from keel line). This allowed Pilot to push herself on the top of the ice and consequently break it. Britnev fashioned the bow of his ship after the shape of old Pomor boats, which had been navigating icy waters of the White Sea and Barents Sea for centuries. Pilot was used between 1864 and 1890 for navigation in the Gulf of Finland between Kronstadt and Oranienbaum thus extending

4794-621: The broadcast station of the radio battalion (in the 1920s) and the Valmet docks until the middle 1970s. The command of the Finnish Navy was located in a red brick building built in the 1880s until 1983 and the Guard Jaeger Regiment used the barracks in the 1960s. The deteriorated barracks buildings were renovated and restored for the use of the Ministry for Foreign Affairs from 1984 to 1989. New side buildings on either side of

4896-461: The cells of the prison into hotel rooms, with sets of two or three cells combined to make up the current hotel rooms. The Best Western Premier Hotel Katajanokka opened in May 2007 with 106 guest rooms. Renovations cost a reported 15 million euro. As a historic building, strict limits were imposed on the redevelopment due to the strict regime of protection for historically significant buildings that

4998-432: The city's district heating network on 10 December 1979. Until this they had been generating their own heat and hot water themselves. The current icebreakers are Kontio , Otso , Voima , Urho , Sisu and Polaris . In summertime, the icebreakers spending their summer at Katajanokka can also be rented for private events. There was a plan to build a house for architecture and design (Armi) in Katajanokka, with

5100-423: The city's zoning plan, until it became a subject of central interest in the 1870s. The zoning plan in the area was confirmed in 1895. According to it, the southern shore of the peninsula was reserved for a harbour and the area north to it as a residential area. The tip of the peninsula remained in the use of the garrison. A number of brick warehouses were built in the harbour area. The neighbouring residential area,

5202-466: The contact between the hull of the vessel and the surrounding ice. As ice pressures vary between different regions of the hull, the most reinforced areas in the hull of an icegoing vessel are the bow, which experiences the highest ice loads, and around the waterline, with additional strengthening both above and below the waterline to form a continuous ice belt around the ship. Short and stubby icebreakers are generally built using transverse framing in which

SECTION 50

#1732790152065

5304-422: The creation of the first polar icebreaker, which was able to run over and crush pack ice . The ship displaced 5,000 tons, and her steam- reciprocating engines delivered 10,000 horsepower (7,500 kW). The ship was decommissioned in 1963 and scrapped in 1964, making her one of the longest serving icebreakers in the world. In Canada, the government needed to provide a way to prevent flooding due to ice jam on

5406-628: The diesel-electric powertrain is the preferred choice for icebreakers due to the good low-speed torque characteristics of the electric propulsion motors, icebreakers have also been built with diesel engines mechanically coupled to reduction gearboxes and controllable pitch propellers . The mechanical powertrain has several advantages over diesel-electric propulsion systems, such as lower weight and better fuel efficiency. However, diesel engines are sensitive to sudden changes in propeller revolutions, and to counter this mechanical powertrains are usually fitted with large flywheels or hydrodynamic couplings to absorb

5508-407: The direction of rotation quickly. During the steam era, the most powerful pre-war steam-powered icebreakers had a propulsion power of about 10,000 shaft horsepower (7,500 kW). The world's first diesel-electric icebreaker was the 4,330-ton Swedish icebreaker Ymer in 1933. At 9,000 hp (6,700 kW) divided between two propellers in the stern and one propeller in the bow, she remained

5610-572: The end of the Age of Sail also featured the egg-shaped form like that of Pomor boats, for example the Fram , used by Fridtjof Nansen and other great Norwegian Polar explorers . Fram was the wooden ship to have sailed farthest north (85°57'N) and farthest south (78°41'S), and one of the strongest wooden ships ever built. An early ship designed to operate in icy conditions was a 51-metre (167 ft) wooden paddle steamer , City Ice Boat No. 1 , that

5712-619: The first North American surface vessels to reach the North Pole. The vessel was originally scheduled to be decommissioned in 2000; however, a refit extended the decommissioning date to 2017. It is now planned to be kept in service through the 2020s pending the introduction of two new polar icebreakers, CCGS  Arpatuuq and CCGS  Imnaryuaq , for the Coast Guard. Russia currently operates all existing and functioning nuclear-powered icebreakers. The first one, NS Lenin ,

5814-511: The fixed pitch propellers. The first diesel-electric icebreakers were built with direct current (DC) generators and propulsion motors, but over the years the technology advanced first to alternating current (AC) generators and finally to frequency-controlled AC-AC systems. In modern diesel-electric icebreakers, the propulsion system is built according to the power plant principle in which the main generators supply electricity for all onboard consumers and no auxiliary engines are needed. Although

5916-403: The formerly Soviet and later Russian icebreakers Ermak , Admiral Makarov and Krasin which have nine twelve-cylinder diesel generators producing electricity for three propulsion motors with a combined output of 26,500 kW (35,500 hp). In the late 2020s, they will be surpassed by the new Canadian polar icebreakers CCGS  Arpatuuq and CCGS  Imnaryuaq , which will have

6018-503: The gas turbines have a continuous combined rating of 45,000 kW (60,000 hp). The number, type and location of the propellers depends on the power, draft and intended purpose of the vessel. Smaller icebreakers and icebreaking special purpose ships may be able to do with just one propeller while large polar icebreakers typically need up to three large propellers to absorb all power and deliver enough thrust. Some shallow draught river icebreakers have been built with four propellers in

6120-727: The historical surroundings. On the western side of Katajanokka is the Stora Enso headquarters designed by the academic Alvar Aalto (1962), a building clad in white marble, inspired by Italian renaissance palaces. It is visible as an ending to the Pohjoisesplanadi street from the Market Square , although a distinctive feature of the building is that it sort of lacks a frontal facade. The decorative red brick Norrmén house built in 1897 had been demolished to make room for Aalto's building. There has been intense debate for several decades about whether Aalto's building fits in with

6222-480: The houses were designed as rental or Hitas houses, which caused a restriction on the cost of construction. For example parking had to be done on ground level. In the latest buildings completed in 2007 parking is handled underground. In the late 19th century, the southern shore of Katajanokka was built into a cargo traffic harbour, which was part of the South Harbour . The Helsinki harbour rail , leading from

SECTION 60

#1732790152065

6324-416: The hull and the ice, and allowed the icebreakers to penetrate thick ice ridges without ramming. However, the bow propellers are not suitable for polar icebreakers operating in the presence of harder multi-year ice and thus have not been used in the Arctic. Azimuth thrusters remove the need of traditional propellers and rudders by having the propellers in steerable gondolas that can rotate 360 degrees around

6426-423: The ice and break it under the weight of the ship. In reality, this only happens in very thick ice where the icebreaker will proceed at walking pace or may even have to repeatedly back down several ship lengths and ram the ice pack at full power. More commonly the ice, which has a relatively low flexural strength , is easily broken and submerged under the hull without a noticeable change in the icebreaker's trim while

6528-433: The ice breaking it. They were used in conjunction with teams of men with axes and saws and the technology behind them didn't change much until the industrial revolution. Ice-strengthened ships were used in the earliest days of polar exploration. These were originally wooden and based on existing designs, but reinforced, particularly around the waterline with double planking to the hull and strengthening cross members inside

6630-409: The ice to break it under the weight of the ship. A buildup of broken ice in front of a ship can slow it down much more than the breaking of the ice itself, so icebreakers have a specially designed hull to direct the broken ice around or under the vessel. The external components of the ship's propulsion system ( propellers , propeller shafts , etc.) are at greater risk of damage than the vessel's hull, so

6732-612: The ice-breaking barge were successful enough to warrant the town purchasing four such ships. Ice breaking barges continued to see use during the colder winters of the Little Ice Age with growing use in the Low Country where significant amounts of trade and transport of people and goods took place. In the 15th century the use of ice breakers in Flanders ( Oudenaarde , Kortrijk , Ieper , Veurne , Diksmuide and Hulst )

6834-455: The icebreaker can also tow the weakest ships. Some icebreakers are also used to support scientific research in the Arctic and Antarctic. In addition to icebreaking capability, the ships need to have reasonably good open-water characteristics for transit to and from the polar regions, facilities and accommodation for the scientific personnel, and cargo capacity for supplying research stations on

6936-576: The level of ice strengthening in the ship's hull. It is usually determined by the maximum ice thickness where the ship is expected to operate and other requirements such as possible limitations on ramming. While the ice class is generally an indication of the level of ice strengthening, not the actual icebreaking capability of an icebreaker, some classification societies such as the Russian Maritime Register of Shipping have operational capability requirements for certain ice classes. Since

7038-469: The lot of the Uspenski Cathedral to commemorate the 100th anniversary of the Treaty of Fredrikshamn . It was seen as a symbol of Russian oppression and in 1919 nationalistic students covered it with tar. It was impossible to get the tar off the rock surface, so the building was dismantled. The buildings on the eastern tip surrounding the Merikasarmi building, in the so-called "new side", consisted already in

7140-424: The mid-19th century – while the centre of Helsinki was being filled with stone buildings – the area was essentially still a wooden shanty town. The eastern part was for a long time a closed military area containing a naval base and shipyard , later a commercial shipyard. It was redeveloped in the 1970s and 1980s into a mainly residential zone, often referred to as the "New Side" of Katajanokka. The new residential area

7242-412: The more spread-out hull loads. While the shell plating, which is in direct contact with the ice, can be up to 50 millimetres (2.0 in) thick in older polar icebreakers, the use of high strength steel with yield strength up to 500 MPa (73,000 psi) in modern icebreakers results in the same structural strength with smaller material thicknesses and lower steel weight. Regardless of the strength,

7344-588: The most powerful Swedish icebreaker until the commissioning of Oden in 1957. Ymer was followed by the Finnish Sisu , the first diesel-electric icebreaker in Finland, in 1939. Both vessels were decommissioned in the 1970s and replaced by much larger icebreakers in both countries, the 1976-built Sisu in Finland and the 1977-built Ymer in Sweden. In 1941, the United States started building

7446-405: The nation's presence in the Arctic and Antarctic regions. As the icecaps in the Arctic continue to melt, there are more passageways being discovered. These possible navigation routes cause an increase of interests in the polar hemispheres from nations worldwide. The United States polar icebreakers must continue to support scientific research in the expanding Arctic and Antarctic oceans. Every year,

7548-498: The new plans had to be redone from scratch. The local community organisation of Katajanokka is called Katajanokkaseura . The organization publishes an annual regional magazine, Katajanokan kaiku (Finnish for "The Echo of Katajanokka"). There is an annual running event called the Katajanokan ympärijuoksu , open for everyone who lives in Katajanokka or has relatives living there. Urban settlement of Helsinki expanded from what

7650-461: The old artillery courtyard were also built at the same time. A gate dating to 1776 was left as part of one of the side buildings. It is part of the artillery magazine built at the same time as the Suomenlinna fortress. Also a copy of the western officers' barracks was built on the eastern side of the barracks according to Engel's original plan. Up to the 19th century, most of the buildings on

7752-473: The prison actually used: for example, prisoners never drank out of tin cups. During the development of Katajanokka in the 1970s and 1980s, many old red brick industrial buildings were spared by converting them for public uses, such as a primary school and an indoors sports arena. There was controversy over the demolition of the former cadet school of the Russian navy , built in the early 20th century. Vacated by

7854-528: The protected object. In the past, such operations were carried out primarily in North America, but today Arctic offshore drilling and oil production is also going on in various parts of the Russian Arctic. The United States Coast Guard uses icebreakers to help conduct search and rescue missions in the icy, polar oceans. United States icebreakers serve to defend economic interests and maintain

7956-455: The sea. The Finnish icebreakers , with the exception of the multiple-use icebreakers, still spend their summers at the Katajanokka shore. Multiple-use icebreakers need to use the harbour only for installing and storage of equipment. This service is offered by the Kotka harbour. After the Valmet dock activity in Katajanokka had gradually moved to Vuosaari the old equipment pier was leased for

8058-399: The shell plating is stiffened with frames placed about 400 to 1,000 millimetres (1 to 3 ft) apart as opposed to longitudinal framing used in longer ships. Near the waterline, the frames running in vertical direction distribute the locally concentrated ice loads on the shell plating to longitudinal girders called stringers, which in turn are supported by web frames and bulkheads that carry

8160-405: The ship MS Viking 5 to Stockholm , Sweden . The site of the old harbour rail yard now hosts a wide avenue called Katajanokanlaituri, and many old warehouse buildings along it have been renovated into hotels and conference centres. The last of the fourteen tripodal cranes on Katajanokka were built in 1959. After this, the Katajanokka harbour could at some times use two cranes for each hatch on

8262-489: The ship was launched in 1993 as NS Ural . This icebreaker is intended to be the sixth and last of the Arktika class. Today, most icebreakers are needed to keep trade routes open where there are either seasonal or permanent ice conditions. While the merchant vessels calling ports in these regions are strengthened for navigation in ice , they are usually not powerful enough to manage the ice by themselves. For this reason, in

8364-413: The ship. Bands of iron were wrapped around the outside. Sometimes metal sheeting was placed at the bows, at the stern, and along the keel. Such strengthening was designed to help the ship push through ice and also to protect the ship in case it was "nipped" by the ice. Nipping occurs when ice floes around a ship are pushed against the ship, trapping it as if in a vise and causing damage. This vise-like action

8466-511: The shore. Countries such as Argentina and South Africa , which do not require icebreakers in domestic waters, have research icebreakers for carrying out studies in the polar regions. As offshore drilling moves to the Arctic seas, icebreaking vessels are needed to supply cargo and equipment to the drilling sites and protect the drillships and oil platforms from ice by performing ice management, which includes for example breaking drifting ice into smaller floes and steering icebergs away from

8568-455: The so-called h - v -curve to determine the icebreaking capability of the vessel. It shows the speed ( v ) that the ship is able to achieve as a function of ice thickness ( h ). This is done by calculating the velocity at which the thrust from the propellers equals the combined hydrodynamic and ice resistance of the vessel. An alternative means to determine the icebreaking capability of a vessel in different ice conditions such as pressure ridges

8670-425: The steel used in the hull structures of an icebreaker must be capable of resisting brittle fracture in low ambient temperatures and high loading conditions, both of which are typical for operations in ice-filled waters. If built according to the rules set by a classification society such as American Bureau of Shipping , Det Norske Veritas or Lloyd's Register , icebreakers may be assigned an ice class based on

8772-474: The stern. Nozzles may be used to increase the thrust at lower speeds, but they may become clogged by ice. Until the 1980s, icebreakers operating regularly in ridged ice fields in the Baltic Sea were fitted with first one and later two bow propellers to create a powerful flush along the hull of the vessel. This considerably increased the icebreaking capability of the vessels by reducing the friction between

8874-523: The summer navigation season by several weeks. Inspired by the success of Pilot , Mikhail Britnev built a second similar vessel Boy ("Breakage" in Russian) in 1875 and a third Booy ("Buoy" in Russian) in 1889. The cold winter of 1870–1871 caused the Elbe River and the port of Hamburg to freeze over, causing a prolonged halt to navigation and huge commercial losses. Carl Ferdinand Steinhaus reused

8976-490: The torque variations resulting from propeller-ice interaction. The 1969-built Canadian polar icebreaker CCGS Louis S. St-Laurent was one of the few icebreakers fitted with steam boilers and turbogenerators that produced power for three electric propulsion motors. It was later refitted with five diesel engines, which provide better fuel economy than steam turbines. Later Canadian icebreakers were built with diesel-electric powertrain. Two Polar-class icebreakers operated by

9078-442: The use of the icebreakers on 24 March 1975. The last ship launched from the dock was the tanker MT Tebostar on 26 April 1974. Individual icebreakers had been spending their summers at the shores of Katajanokka also before this. For example in summer 1971 an old system was kept in force, where two icebreakers were at Jätkäsaari , three at Hietalahti and three near the Valmet dock in Katajanokka. The icebreakers were connected to

9180-406: The vessel moves forward at a relatively high and constant speed. When an icebreaker is designed, one of the main goals is to minimize the forces resulting from crushing and breaking the ice, and submerging the broken floes under the vessel. The average value of the longitudinal components of these instantaneous forces is called the ship's ice resistance. Naval architects who design icebreakers use

9282-524: The western side of Katajanokka were old wooden buildings built in the 18th century, already badly deteriorated, and warehouses. Exceptions to this included the Uspenski Cathedral built in 1868, the building of the Mint of Finland (1836), the Helsinki County Prison located near the garrison and some apartment buildings built in the very end of the century. Katajanokka had been left outside

9384-482: Was already well established. The use of the ice breaking barges expanded in the 17th century where every town of some importance in the Low Country used some form of icebreaker to keep their waterways clear. Before the 17th century the specifications of icebreakers are unknown. The specifications for ice breaking vessels show that they were dragged by teams of horses and the heavy weight of the ship pushed down on

9486-431: Was also praised for taking the architectural and cultural history of the surrounding area into account. Open spaces were sought to be measured in regard of the actual number of visitors. However, because of design norms, the building efficiency remained lower than that of the old part. The red brick facades were ordered to be laid in place, even though this was during the golden age of element construction. A large number of

9588-506: Was built for the city of Philadelphia by Vandusen & Birelyn in 1837. The ship was powered by two 250- horsepower (190 kW) steam engines and her wooden paddles were reinforced with iron coverings. With a rounded shape and strong metal hull, the Russian Pilot of 1864 was an important predecessor of modern icebreakers with propellers. The ship was built on the orders of merchant and shipbuilder Mikhail Britnev . She had

9690-452: Was completed at Lauzon, Quebec. A considerably bigger and more powerful ship than Labrador , John A.Macdonald was an ocean-going icebreaker able to meet the most rigorous polar conditions. Her diesel-electric machinery of 15,000 horsepower (11,000 kW) was arranged in three units transmitting power equally to each of three shafts. Canada's largest and most powerful icebreaker, the 120-metre (390 ft) CCGS  Louis S. St-Laurent ,

9792-471: Was delivered in 1969. Her original three steam turbine, nine generator, and three electric motor system produces 27,000 shaft horsepower (20,000 kW). A multi-year mid-life refit project (1987–1993) saw the ship get a new bow, and a new propulsion system. The new power plant consists of five diesels, three generators, and three electric motors, giving about the same propulsion power. On 22 August 1994 Louis S. St-Laurent and USCGC  Polar Sea became

9894-440: Was designed to pass through Hakaniemi . There was a plan to build premises for the Helsinki emergency dispatch centre in Katajanokka. However, the rent of the premises was seen as too high, and the emergency dispatch centre was moved to Kerava . A new user for the caves was found, but its identity has not been made public. Explosions during the excavation of the caves caused damage in the properties along Luotsikatu. Katajanokka

9996-423: Was finally demolished in autumn 2006. However, additional problems resulted: Contrary to what the city of Helsinki and the architecture bureau responsible for the new building had thought, there was no solid rock bottom underneath the old building, but only scattered rocks here and there. Because the original building had stood there since Czarist Russia, no original construction plans were available, and therefore

10098-496: Was improved on 3 May 1994 to improve passport control and customs activity. All persons present at the harbour area had to have an identity document with a photograph with them. In early May 1997 the gate control of the entire South Harbour was transferred over to a security company. The harbour activity also had side effects. From the 19th century to the middle 20th century Katajanokka was an area of ill repute, where illegal sales of liquor and prostitution were often practised. For

10200-581: Was launched in 1957 and entered operation in 1959, before being officially decommissioned in 1989. It was both the world's first nuclear-powered surface ship and the first nuclear-powered civilian vessel . The second Soviet nuclear icebreaker was NS Arktika , the lead ship of the Arktika class . In service since 1975, she was the first surface ship to reach the North Pole , on August 17, 1977. Several nuclear-powered icebreakers were also built outside

10302-452: Was protected by a belt of ice-floe resistant flush skin-planking along the variable water-line, and had a false keel for on-ice portage . If a koch became squeezed by the ice-fields, its rounded bodylines below the water-line would allow for the ship to be pushed up out of the water and onto the ice with no damage. In the 19th century, similar protective measures were adopted to modern steam-powered icebreakers. Some notable sailing ships in

10404-524: Was ultimately only built in 1844. The name "Katajanokka" literally means "Juniper Point" but the connection with junipers is just a coincidence resulting from a mistranslation. The neighbourhood was originally known in the 17th century by the Swedish name Estnäs Skatan (" Estnäs Point"). The Finnish -speaking population did not understand Swedish, so the word skata ("point") became kataja ("juniper"). The Swedish name Skat Udden can be found from

#64935