''Miscaroo'' was an

icebreaking 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 ...

anchor handling tug supply vessel Anchor Handling Tug Supply (AHTS) vessels are mainly built to handle anchors for oil rigs, tow them to location, and use them to secure the rigs in place. AHTS vessels sometimes also serve as Emergency Response and Rescue Vessels (ERRVs) and a ...

built by Vancouver Shipyards for BeauDril, the drilling subsidiary of

Gulf Canada Resources Gulf Canada was a Canadian integrated petroleum company that existed between 1944 and 2001. Gulf Oil Corporation began operating in Canada in 1942, and two years later formed a Canadian subsidiary called the Canadian Gulf Oil Company. In 1956 Cana ...

, in 1983. She was part of a fleet of Canadian icebreakers used to support offshore

oil exploration Hydrocarbon exploration (or oil and gas exploration) is the search by petroleum geologists and geophysicists for hydrocarbon deposits, particularly petroleum and natural gas, in the Earth's crust using petroleum geology. Exploration methods V ...

in the

Beaufort Sea The Beaufort Sea ( ; ) is a marginal sea of the Arctic Ocean, located north of the Northwest Territories, Yukon, and Alaska, and west of the Canadian Arctic Archipelago. The sea is named after Sir Francis Beaufort, a Hydrography, hydrographer. T ...

. In the 1990s, the vessel was acquired by Canadian Marine Drilling (Canmar) and renamed ''Canmar Miscaroo''. In 1998, she was purchased by

Smit International Smit Internationale N.V. (or Smit International) is a Dutch company operating in the maritime sector. Founded in 1842 by Fop Smit, it provided towing services in the Port of Rotterdam. Within its first decades, it branched into shipbuild ...

and served in the

Sakhalin Sakhalin ( rus, Сахали́н, p=səxɐˈlʲin) is an island in Northeast Asia. Its north coast lies off the southeastern coast of Khabarovsk Krai in Russia, while its southern tip lies north of the Japanese island of Hokkaido. An islan ...

oil fields as ''Smit Sakhalin'' until 2017 when the 34-year-old icebreaker was sold for scrapping in China.

History

Development and construction

In the mid-1970s, oil companies began drilling in the Canadian part of the

. In order to overcome the relatively short operating window of

drillship A drillship is a merchant vessel designed for use in exploratory offshore drilling of new oil and gas wells or for scientific drilling purposes. In recent years the vessels have been used in deepwater and ultra-deepwater applications, equipped ...

s during the ice-free season (100 to 110 days a year) and the water depth limitations of artificial dredged islands,

began developing an Arctic drilling system consisting of two mobile drilling units: a Mobile Arctic Caisson (MAC) that could be submerged and filled with gravel to form an artificial drilling island in waters up to in depth and a floating Conical Drilling Unit (CDU) designed for drilling in water depths between while afloat. These units, each capable of completing one exploration well per year, would be supported by four Arctic Class 4 vessels: two large icebreakers providing 24-hour ice management and standby services on the drilling site and two smaller icebreaking vessels responsible for anchor handling and supply runs between the drilling rigs and coastal bases. By 1982, both drilling units and all four icebreaking vessels were under construction in Canada and Japan for BeauDril, Gulf Canada's drilling subsidiary, and the company had committed itself to a billion-dollar exploration program between 1983 and 1988. The smaller icebreakers were designed by the Canadian naval architecture company

Robert Allan Ltd Robert Allan Ltd. is Canada's oldest privately owned Consulting firm, consulting Naval architecture, Naval Architectural firm, established in Vancouver, British Columbia in 1930. Their experience includes designs for vessels of almost all types ...

and the construction of one vessel was awarded to Vancouver Shipyards in

Vancouver, British Columbia Vancouver is a major city in Western Canada, located in the Lower Mainland region of British Columbia. As the List of cities in British Columbia, most populous city in the province, the 2021 Canadian census recorded 662,248 people in the cit ...

, in December 1979. The keel of the vessel was laid on 5 July 1982 and she was launched on 13 March 1983 as ''Miscaroo''. The name, Loucheaux for "owl", had been chosen in a naming contest by Northern Territories school children.Specialisation in diversity - the West Coast demonstrates what Canadian yards do best. G. E. Mortimore, Canadian Shipping and Marine Engineering, October 1983: 16–17. She was completed on 29 July 1983 and immediately headed for the Beaufort Sea. ''Miscaroo''s sister ship, '' Ikaluk'', was built at Nippon Kōkan K. K. Tsurumi Shipyard in Japan and delivered in April 1983. Despite having been built at two different shipyards on the opposite sides of the world, the two vessels were nearly identical with most of the major components being supplied by Gulf Canada to both shipyards. These vessels were the first Canadian Arctic vessels powered by diesel engines manufactured by

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 ...

''Miscaroo'' and ''Canmar Miscaroo'' (1983–1998)

Between 1983 and 1990, BeauDril's mobile drilling units drilled a total of nineteen exploratory wells in the Canadian part of the Beaufort Sea with the support of ''Miscaroo'' and other icebreaking vessels: nine with the Mobile Arctic Caisson '' Molikpaq'' and ten with the Conical Drilling Unit ''

Kulluk ''Kulluk'' was an ice-strengthened drill barge that was used for oil exploration in the Arctic waters. She was constructed by Mitsui Engineering & Shipbuilding in Japan in 1983 and operated in the Canadian Arctic until 1993 when she was mothballed ...

''. Twelve wells alone were drilled in the Amauligak prospect, the most significant oil and gas field discovered in the region, but the high expectations for the Beaufort Sea were not met: the area was characterized by a large number of small, widely scattered resources. ''Molikpaq'' was mothballed after completing the last well in 1990. However, ''Kulluk'' was used to drill a total of four wells in 1992 and 1993 for ARCO Alaska on the American part of the Beaufort Sea before being cold-stacked at

Tuktoyaktuk Tuktoyaktuk ( ; , ) is an Inuvialuit hamlet near the Mackenzie River delta in the Inuvik Region of the Northwest Territories, Canada, at the northern terminus of the Inuvik–Tuktoyaktuk Highway.Montgomery, Marc"Canada now officially connected ...

.Beaufort Sea Exploration Wells
Bureau of Ocean Energy Management. In 1993, BeauDril's flotilla of drilling rigs, icebreakers and support vessels was purchased by Canadian Marine Drilling (Canmar). The drilling subsidiary of

Dome Petroleum Dome Petroleum Limited was a Canadian independent petroleum company that existed between 1950 and 1988. The company was founded as a subsidiary of Dome Mines and was built by Jack Gallagher, who remained with the company until 1983. In 1988 Dom ...

(later Amoco Canada) had been BeauDril's main competitor in the Beaufort Sea for more than a decade and the merger of two former rivals created the world's largest fleet of commercial Arctic vessels. Despite declining activity in the Canadian Arctic, Amoco saw Canmar and its expertise as a long-term asset and tried to find work for ''Miscaroo'' (''Canmar Miscaroo'' since 1995), from other areas such as the

North Sea The North Sea lies between Great Britain, Denmark, Norway, Germany, the Netherlands, Belgium, and France. A sea on the European continental shelf, it connects to the Atlantic Ocean through the English Channel in the south and the Norwegian Se ...

.Smit Sakhalin scrapped
Tugs, Towing & Offshore Newsletter, 22 October 2017

''Smit Sakhalin'' (1998–2017)

In the end, Amoco could not make profit from maintaining Canmar and sold the company's remaining assets, including ''Canmar Miscaroo'', in 1997 to an international consortium of shipping companies. After having been reflagged to Bahamas and renamed ''Iscaroo'' for a brief period of time, the vessel was purchased by the Dutch company

in 1998 and renamed ''Smit Sakhalin''. The vessel left Rotterdam in April 1998 and arrived in Singapore where the management was taken over by Smit's local subsidiary.Nieuwsbrief 128
World Ship Society Rotterdam Branch, 14 October 2006. At the same time, the company also purchased ''Miscaroo''s sister ship, ''Ikaluk'', and renamed her ''Smit Sibu''. The two former Canadian offshore icebreakers were deployed together at the Vityaz Production Complex during the first phase of the Sakhalin-2 project in the seasonally frozen

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 ...

. In addition to providing year-round supply services for the ''Piltun-Astokhskoye-A'' platform (the former ''Molikpaq''), they served as ice management and standby vessels for the floating storage and offloading (FSO) vessel ''Okha'' and its single anchor leg mooring (SALM) buoy. The icebreakers were used to assist the raising and lowering of the SALM buoy and the beginning and end of the production season, and to support loading operations together with other icebreaking vessels until the ice conditions became too severe.Reed, I. C. (2006)
Oil Exploration and Production Offshore Sakhalin Island
ICETECH'06 proceedings. In 2006, the management of ''Smit Sakhalin'' was transferred to FEMCO Management and she was converted to dedicated stand-by vessel at Keppel Tuas shipyard in Singapore. She continued in this role after the ice management operations at Vityaz Production Complex ended when the production platform was connected to a subsea pipeline in 2008.Oil Exploration and Production Offshore Sakhalin Island - Ice Management and Marine Operations
Ian Reed, Shell Oil, 12 May 2014. Her management was returned to Smit in 2013. The 34-year-old ''Smit Sakhalin'' was sold for recycling in 2017 and arrived at the scrapyard in Jiangyin, China, in September.

Design

General characteristics

''Miscaroo'' was

long overall Length overall (LOA, o/a, o.a. or oa) is the maximum length of a vessel's hull measured parallel to the waterline. This length is important while docking the ship. It is the most commonly used way of expressing the size of a ship, and is also u ...

and at the waterline. She had a moulded beam of at the widest point of the hull and at the waterline. The vessel had a

light displacement The displacement or displacement tonnage of a ship is its weight. As the term indicates, it is measured indirectly, using Archimedes' principle, by first calculating the volume of water displaced by the ship, then converting that value into weig ...

of 3,650 tons but when loaded to the design draught of , she displaced 5,050 tons of water. Her icebreaking hull form, developed at the Hamburgische Schiffbau-Versuchsanstalt (HSVA) ice tank in Hamburg, Germany, featured a heavy forefoot wedge to deflect ice floes and large bossings to protect propellers and rudders from damage, and was strengthened to Canadian Arctic Shipping Pollution Prevention Regulations (CASPPR) Arctic Class 4 requirements. The hull was made of cold-resistant high strength steel sourced from Japan and coated with the low-friction Inerta 160 epoxy paint. Inside, ''Miscaroo'' provided comfortable accommodation for six officers and 16 crew members in single cabins even when the ambient temperature dropped to . In addition, she had two six-person cabins for 12 passengers commuting between oil rigs and coastal bases. Designed to provide the drilling units with bulk cement, fuel oil and drinking water, ''Miscaroo'' had cargo tanks and an open cargo deck abaft of the deckhouse. Her hydraulic quadruple-drum waterfall-type winch could be used to tow ''Kulluk'', BeauDril's ice-strengthened drilling unit, as well as deploy and retrieve its anchors at the drilling site.

Power and propulsion

''Miscaroo'' had a diesel-mechanical propulsion system with four medium-speed

diesel engine The diesel engine, named after the German engineer Rudolf Diesel, is an internal combustion engine in which Combustion, ignition of diesel fuel is caused by the elevated temperature of the air in the cylinder due to Mechanics, mechanical Compr ...

s driving two shafts through twin input-single output gearboxes. The main engines were eight-cylinder

Vasa 8R32 medium-speed

s rated at each. The flexible couplings in the Lohmann & Stolterfoht Model GVA 1400 SO single-stage reduction gearboxes allowed choosing between fuel-saving cruise in open water using two engines or full icebreaking power with all four engines running. The four-bladed stainless steel

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, manufactured by LIPS Canada, had a diameter of and were placed in fixed

nozzles A nozzle is a device designed to control the direction or characteristics of a fluid flow (specially to increase velocity) as it exits (or enters) an enclosed chamber or pipe. A nozzle is often a pipe or tube of varying cross sectional area, ...

. For maneuvering, the vessel had twin rudders, a OmniThruster water jet thruster in the bow and an KaMeWa tunnel thruster in the stern. Onboard electricity was produced by two

Caterpillar Caterpillars ( ) are the larval stage of members of the order Lepidoptera (the insect order comprising butterflies and moths). As with most common names, the application of the word is arbitrary, since the larvae of sawflies (suborder ...

auxiliary diesel generators or a smaller Caterpillar 3404 diesel generator which was intended to be used when the vessel is at dock. In addition, the gearboxes incorporated 1,200kVA shaft alternators. At full power, ''Miscaroo'' was designed to break level ice with a speed of . The icebreaking was further assisted by an active hull lubrication system incorporated to the OmniThruster unit: nozzles along the forward half-length of the vessel could be used to eject air/water mixture between the hull and the ice to prevent the vessel from becoming stuck in ice. In open water, ''Miscaroo'' could achieve a speed of with four engines running and in economic cruising with two engines.

References

{{Icebreakers of Canada Icebreakers of Canada Icebreakers of Russia 1983 ships Ships built in North Vancouver History of the petroleum industry in Canada