Antarctic II: Newly lengthened and upgraded Shetland midwater trawler starts well on herring

Shetland skipper John William Stewart and the crew of the midwater trawler Antarctic II LK 145 took their 2017 herring quota within three weeks of the vessel completing an extensive six-month vessel upgrade project in Norway, reports David Linkie.

Above: The new-look Shetland midwater trawler Antarctic II arriving at Lerwick after being upgraded and lengthened in Norway. (Photo: Ivan Reid)

While the external changes to Antarctic II – including the vessel’s LOA being increased by 7.8m to 69.7m, a new watertight full-length boat deck, and a new whaleback – are immediately apparent, the internal changes are equally impressive and involved.

The fact that the crew rigged Antarctic II out in just 48 hours after returning to Lerwick, before immediately departing to fish herring north of Orkney, provides an initial indication of the efficiency with which the work was completed, within a tight timescale at the Vard Langsten Shipyard in Tomrefjord.

Being finished in time for the late summer herring fishery gave the crew the opportunity to familiarise themselves with the different handling and working characteristics of the new-look Antarctic II. At the same time, it gave the opportunity to prove the new fish-pumping and storage systems, before starting to fish North Sea mackerel later this month, which was an essential requirement for skipper John William Stewart.

Antarctic II landed to Pelagia Shetland, in Lerwick, following an initial shake-down trip, during which fishing operations went according to plan. Although the only boat searching for herring on the grounds towards the end of the season, apart from the Fraserburgh midwater trawler Christina S, thereby increasing the challenge of locating suitable marks, Antarctic II subsequently landed two good shots in Killybegs, before returning to Lerwick in preparation for the mackerel fishery.

Skipper John William Stewart said: “From the outset, the major changes carried out in the past six months performed smoothly, and confirmed that significant benefits, both in terms of fishing efficiency and crew safety, will accrue in years to come. Some of the modifications involved, particularly in creating a new pump room, were extremely complex, but everyone at the shipyard showed their experience and skill to complete a first-class job, which we are more than satisfied with.”

The trend towards increasingly severe weather in January and February coincides with the time of year when Antarctic II usually fishes mackerel in the North Atlantic, west of Scotland and Ireland. This was one of the main considerations for skipper John William Stewart, and his fellow partners in the Fiskebas Fishing Company Ltd, in making the decision to upgrade the 61.9m Antarctic II, which was built by Flekkefjord Slipp and Maskinfabrikk AS in 2004.

Given the international nature of pelagic fishing and marketing where the midwater trawler was immediately berthed on Langsten Shipyard’s covered dry dock in preparation for the hull being cut in half at the fore end of the deck casing and the engineroom bulkhead.

This work involved welding 20mm square key steels to the hull to form a 15mm gap that served as a guide during the cutting process. The hull was cut from the gunwale rail to the keel using a diamond-encrusted wire. With a cable speed of 18m per second, the wire was kept cool with water nozzles.

When Antarctic II had been cut in half, the fore and aft sections were pulled before a new 7.8m hull section – prefabrication of which was completed before the vessel left Shetland – was lifted into position.

As a result of the additional displacement associated with inserting the hull section amidships, Antarctic II now sits 400mm higher in the water at the start of a trip. In addition to further enhancing crew safety by increasing the vessel’s freeboard, this has also resulted in increased speed and propulsion efficiency.

Rather than simply including an additional three RSW tanks in the new section, which a few years ago was viewed as being the norm in similar situations, and considered to be the easier option, the decision was taken to maintain the vessel’s existing nine-tank arrangement. The capacity of this has been increased from 1480m3 to approximately to 2000m3.

A key benefit of this is that the bulkhead of the forward tier of RSW tanks was moved aft by a few frames, to allow for a complete re-arrangement of the vessel’s RSW pump room and manifold piping in plastic. This work also included installation of a water-flow monitoring system to all RSW tanks.

Additional double bottom tanks in the new hull section have increased the vessel’s fuel capacity from 385m³ to nearly 500m³.

When the midships section was in situ, work commenced to fit a new watertight full-length boat deck from the accommodation casing forward to the existing whaleback. At the same time, a new whaleback was fabricated at the side of the drydock before being lifted into place to enclose the previously open mooring and 6t anchor winches forward.

Two hydraulically-operated mooring platforms extending down to the deck of the original whaleback are incorporated into the new structure. While mooring platforms are now commonplace on new oil standby and dive support vessels, Antarctic II is the first UK pelagic vessel to feature them. The mooring winches can be operated from controls located next to the opening, enabling the crewman to tighten the mooring ropes with continual line of vision.

Enclosing the shelterdeck amidships meant that the previous fish-pumping arrangements on the starboard side were elevated onto the level of the new watertight boat deck. This modification also gave the opportunity to fit a new pump through fish hose reel as part of a complete new MMC fish distribution/water separator system that is set into the upper deck to ensure that water-tightness is maintained.

Antarctic II

Antarctic II was the last of four midwater trawlers designed by Skipsteknisk AS of Aalesund and built by Flekkefjord Slipp and Maskinfabrikk AS in 2003-2004 for Whalsay-based partnerships. The other three were the similarly-sized Adenia LK 193, together with the 70m Research LK 62 and Charisma LK 362.

When delivered in March 2004, to replace the 60m Antarctic LK 145 – purchased from Eammon McHugh of Killybegs in 1997, as Antarctic D 97 following the sale of the 126ft steel-hulled purser Fiskebas LK 145, which skipper John William Stewart and partners bought from Floro, Norway in 1986 – Antarctic II had a LOA of 61.9m, 13.5m of beam and a depth to shelterdeck of 8.6m.

Antarctic II has subsequently performed consistently well when following the customary seasonal pattern of pelagic activity, based around the early year mackerel fishery west of Scotland and Ireland, followed by herring activity, usually in the second half of August/early September, before starting to fish mackerel again in the North Sea in October.

Antarctic uses a set of 11m² Thyboron midwater doors to spread herring and mackerel midwater trawls with fishing circles of between 1080m and 1400m, supplied by Swan Net-Gundry Ltd of Killybegs.

The midwater trawls on Antarctic are worked from two 52t net drums positioned aft at first deck level ahead of double sets of net and toe end weight tracks that lead to twin openings across the transom stern.

Antarctic II is equipped with a full package of Karmoy Winch deck machinery. This includes two 79t core pull split trawl winches operated through a Karm 3010 autotrawl system, together with a 50t lifeline and 36t mid/tail end winches and an 18in fishpump.

Antarctic II is powered by a MaK 9M32 main engine (4320kW @ 600rpm) that drives a 4000mm-diameter four-bladed CP propeller system housed in a high-performance nozzle through a matching Scana Volda 4.13:1 reduction gearbox.

Electrical power generated by a Leroy Somer 2,400kVA shaft generator is supplemented by two Mitsubishi S6RM DPTK 635kW auxiliaries and two Mitsubishi 6D24TC harbour gensets.

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