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Quest For Quality Influences european Vessel Production

Killybegs in Ireland is home to just 3,000 people and around 45 fishing boats, yet its fame in commercial fishing circles has spread far and wide. Fishing and associated services provide employment to half the population, making it one of the most fishing dependent communities in the world. Skippers from the port are regularly "borrowed" by emerging nations as experts on the latest techniques and, for such a small port, Killybegs boasts more than its share of Europe's biggest fishing vessels.

The latest arrival, Atlantic Challenge (See picture, page 40), represents a significant bench mark in the development of the so-called supertrawler. Although big by any standards at 230 ft. x 44.5 ft. (70 m x 13.6-m), and a full 16 ft. (5 m) longer than the vessel she replaces — Atlantic Challenge has 35 percent less fish hold capacity.

This apparent anomaly is deliberate, as the new vessel has been built for speed and with three times the chilling capacity of the old trawler. With quotas as they are, the profit is in quality not quantity; with premium prices being paid for the best fish.

Built in Norway at family-run Hellesoy Shipyard to a design by celebrated Norwegian naval architects Vik & Sandvik, the vessel features a hull form which is much narrower in the beam at the waterline. According to its designers, this shape is to ensure that the maximum possible speed is obtained from the Wartsila 16V32E diesel and 3,900-mm Wichmann propeller. On trials the vessel achieved 17 knots, seven knots faster that its predecessor. This level of performance is considered vital by owner Killybegs Fishing Enterprises, for guaranteeing that the catch is delivered to the buyers in prime condition.

The company firmly believes that it makes sense to sacrifice carrying capacity for speed and quality. An increased free running speed will also allow the vessel to seek out grounds further afield.

Ironically, most of the catches are supplied to Norwegian processors, and it was their demands for better quality fish that prompted the vessel, conceived and built in Norway, to be ordered by the Irish company.

The impressive wheelhouse electronic specification includes a Racal-Decca Bridgemaster radar, ARCS electronic chart system, Sercel DGPS, a Robertson AP9 MKII autopilot which forms the "brain" of a Robfisk rudder and thruster control arrangement, and Furuno ARPA.

A massive array of fish finding electronics incorporates a Simrad SD 570 omni-sonar for long distance detection, a medium range Kaijo Denki scanning sonar, a Simrad ES381 with split beam for deepwater fish finding and a Furuno color sounder. Few fish are expected to escape.

Atlantic Challenge will mainly work the mid- Atlantic ridge from Iceland to the Azores with a 15-person crew, joining other recently built Killybegs supertrawlers, including the matched pair Father McKee and Brendelen and the Hellesoy-built giant — 340-ft. (104-m) — pelagic freezer Veronica.

In all, some 20 of the vessels at the port are pelagic trawlers. Although drawn from such a small population, it is remarkable that so many skippers have managed to invest millions of dollars without grant assistance.

Similar considerations regarding quality were involved in another recently delivered Vik & Sandvik design. Built in Holland at the Yssel- Vliet Combinatie (YVC) yard for a Dutch owner's German-based operation, Helen Mary is a 383-ft. (116.7-m) pelagic trawler which incorporates a centralized computer system for controlling and monitoring the quality of the catch, including the handling, temperature control, grading, freezing, pumping and packing processes.

Furthermore, the owner and customers on shore can check the state of the catch, including the time taken to freeze, through the monitoring computer via a satellite link. This particular feature is of considerable importance as the vessel will fish over a wide area, from the Barents Sea to the West African coast of Mauritania.

Helen Mary is also thought to be the first vessel of its size to be equipped with an onboard slurry ice system capable of freezing 20 tons of fish from 15 degrees C in only 20 minutes.

According to the owner, the vessel will be able to land the best quality frozen fish in the world. A pair of MaK 9M32 diesels provide 5,300 hp to drive a 4,300-mm stainless steel propeller inside a nozzle, but once again, the comprehensive battery of fish detection equipment is the most noteworthy. Simrad alone has provided an SR240 omni-sonar, FS900 trawl sonar and three independent color echo sounders, two of which are dual frequency. Acceptance of Shetland tugs ends speculation Tystie and Hunter, two powerful Voith tractor tugs, have finally been delivered by the Ferguson yard in Scotland and accepted by the customer, Shetland Towage, ending more than six months of speculation. The first of the tugs to be completed (pictured on page 38) was expected to enter service at the beginning of this year, but was rejected by Shetland Towage for failing to achieve the specified astern bollard pull.

Amid much secrecy on the part of the builder, the finished vessel, Tystie, returned to drydock for modification, and work on the other tug, nearing the final stages, was halted. Details as to the nature of the alterations were not forthcoming from any source.

However, at last the silence was broken with the announcement that new blades, some 10 in. (250-mm) longer, have been fitted to the Voith Schneider cycloidal propellers on both tugs, and the protection plates have been repositioned. These changes have reportedly enabled the vessels to produce 56 tons ahead, 51 tons astern and a free running speed of 13.5 knots on sea trials. The owner claims that these figures not only exceed the specified requirements, but make the vessels the most powerful tractor tugs in British waters. Commenting on the news that his company had eventually seen fit to accept the vessels, Shetland's Managing Director Capt. Eddie Dowswell said: "We cannot pretend that the difficulties that we have suffered have been mere teething troubles; we experienced a serious and very worrying technical problem. That has now been resolved in a workmanlike manner, albeit at considerable cost to all concerned. We are now confident that we have two excellent tugs that will acquit themselves very well in all the roles we intend for them. A huge amount of work has gone into their design." Now that the performance shortfall has been remedied, Shetland seems to have succeeded in realizing its goal of operating two big and potent tugs ideally suited to the harsh environment of the Sullom Voe oil terminal. Measuring 123.4 x 44-ft. (37.60 x 13.40 m) with a maximum draft of 18.7 ft. (5.7 m), Tystie and Hunter are each powered by a pair of 2,720-hp (2,030- kW) Caterpillar 3606 diesels, the first from this range to be employed in the U.K. towage industry. Both vessels are classified FiFi 1, being equipped with two foam water monitors with throws of 390 ft. (120 m) and self protection drenching systems. For pollution control duties, the tugs are fitted with spraying equipment and have a total onboard dispersant capacity of 14 tons.

Double-enders take new age propulsors Danish yard Orskov Staalskibsvaerft AS in Frederikshavn has now finalized the design for two double-ended train/car ferries on order from DSB Rederei AS, Danish State Railways. The ships, which will operate on the 45-min. crossing between Rodby in Denmark and Puttgarden in Germany on the so-called Birdflight route, will reportedly be environmentally conscious as well as attractive in appearance, due to an engineering design philosophy which has taken various criteria into consideration in order to create the desired effect.

Measuring 465.7 x 83.3-ft. (142 x 25.4-m) beam over fender, with a draft of 19 ft. (5.8 m), each vessel has two vehicle decks, with an upper level capacity of 126 cars and a lower capacity of 160 cars. Approximately 900 passengers can be carried in modern, comfortable public spaces.

In keeping with other ferries in the DSB fleet, including double-enders, a diesel-electric system was specified early on in the proceedings, but conventional propellers and rudders were abandoned after tests, as power was substantially less than required.

The decision to link four 3,000-kW ABB Sami Megastar diesel-electric power units to four 3,000-kW Contaz propulsors not only ensured adequate power but bucked convention in terms of naval architecture.

Conventional double-ended ferries are normally fitted with one center propeller and a flap rudder at each end of the ship, but the new ferries, with two propulsors fitted at the sides of each end, have made it possible to obtain an optimum hull form and to fit a specially designed bulbous bow at each end. Based on the model test, this concept, together with the high efficiency of contra-rotating propellers, is expected to exceed savings of as much as 20 percent in fuel consumption, as compared with a conventional design. An additional benefit is that the building costs of the ships have been reduced with lower power and noise insulation demand.

The decision to opt for the new generation Contaz propulsor unit is, according manufacturers Aquamaster-Rauma in Finland, a milestone in its strategy to make Contaz a well known brand of azimuthing thrusters for oceangoing ships. The incorporated contra-rotating propellers, known for high efficiency, low noise and vibration level, are also streamlined in appearance to provide higher speed than traditional thrusters. The units are also designed for longer life. The DSB order is only the second to be received for Contaz since its introduction, although these units could be the first to see active commercial service if Orskov delivers the lead ship on schedule in May 1997.

The first units were delivered early this year for an RMT 6000 Norwegian platform supply vessel building at Brattvaag Shipyard in Norway, for delivery next summer to DOF Management AS (two smaller units, each producing 2,200 kW have been purchased).

Additional benefits of the propulsion system reportedly include short maneuvering time and all-weather operation on a 24-hour basis. The normal service speed will be 16.5 knots, timing the crossing at 44 minutes, and at maximum service speed of 18.5 knots, a 39-min. schedule could be attained. Twin engine rooms and twin wheelhouses are specified and simultaneous loadings and discharge can be carried out on both deck levels.

Thames taxi design goes commercial White Horse Ferries, the U.K. company that has been conducting practical assessment tests on river taxi viability on the River Thames, is now preparing to add two new craft to its fleet for operation in the heart of London. The tests, which have involved the design and development of special high speed, low wash vessels, have resulted not only in the creation of an ideal river passenger boat, but also in a design which the ferry operator hopes to market for a wide range of workboat applications.

The R&D program has lasted five years in total, with initial concepts tested on a pre-production, 12-seater reduced scale craft, Ebenezer Scrooge. Analysis conducted during its threeyear operation led to a honed design concept for the 12/60 trimaran ferry, with build efficiency taken greatly into account in order to facilitate series production. Build efficiency reduces the capital cost per passenger seat and operating costs, bringing total expenditure in line with road operated public transport.

The first of the new 12/60 ferries, Martin Chuzzlewit, built by Lay Construction, sister company to White Horse Ferries, is now in service on the lower reaches of the Thames, operating between Gravesend in Kent and Tilbury in Essex. With a long, slender displacement, triple hull form, the craft provides a wider deck platform than could be accommodated on a monohull, and with additional stability. The trimaran concept was deemed preferable to a catamaran arrangement, as it allows more flexibility over deck plan arrangements and accommodations. According to the operators, the craft is also considerably more maneuverable than either monohull or catamaran, is more cost-efficient to build and operate, and is considered safer.

The design has also facilitated a unique docking arrangement. In plan form, the craft is wedge shaped forward, enabling the vessel to dock in a "V" berth, which White Horse has fabricated into its piers at Gravesend and Tilbury. This method stabilizes the vessels for passenger boarding and alighting, and is said to be safer and faster than the traditional means of mooring craft.

The hull, deck and superstructure are all built in glass reinforced plastic (GRP), with a single skin laminate on each hull with keel beam, frame bulkhead and stringer arrangement, providing considerable strength. Foam sandwich construction has been adopted for the deck and superstructure, and fire retardant resins were used in the engine room and passenger areas.

Measuring 59.11 x 18-ft.(18.26 x 5.5-m), with a loaded draft of 2.95 ft. (0.9 m) and loaded displacement of 16.19 tons, the 12/60s are being fitted with either Sabre Perkins 185 engines, producing 185 hp at 2100 rev/min — as on Martin Chuzzlewit — or the new Deutz 1015 V8 watercooled engine, which offers higher speeds with 473 hp at 2100 rev/min. The latter has been selected for Wilkins Micawber, the first of the two craft now in build, scheduled for service in late fall. The sister vessel will also have a Dickensian name.

Both engines power an Ultrajet 375 with an appropriately matched impeller. The waterjet manufacturer, Ultra, has also developed a very comprehensive electro-hydraulic system with full intelligent feedback joystick control of the jets, steering and reversing bucket. A speed of around 20 knots is reportedly attainable.

Each vessel is designed for single crew operation although, in this instance, a maximum of only 12 passengers can be carried to comply with Marine Safety Agency regulations. Sixty passengers can be carried when operated with two crew so that additional lifesaving equipment can be manned. Passenger accommodation is located amidships with an open aft deck and covered fore deck, astern of the wheelhouse, which is located at the bow. The passenger saloon has seating for 50 passengers and a wheelchair, with the first 12 seats aircraft style. The remainder are of molded GRP with soft upholstery. The outside deck has additional seating for eight passengers and room to stow bicycles. Ample standing room is also available on both decks and in the saloon.

Safety has featured strongly in the design concept and the 12/60s have 12 fully watertight compartments, each with two automatic bilge pumps.

In the event of the main hull or one of the sponsons suffers from collision damage, the remaining buoyancy would reportedly be sufficient for keeping the vessel afloat. The vessels are built to Lloyd's approved drawings.

The two trimarans currently in build will be employed to open a half-hour service between Charing Cross and Canary Wharf, initially on a Monday-Friday basis. Ebenezer Scrooge will be utilized as a standby vessel on the route.

 
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