VESSEL REVIEW | Thorunn Thordardottir – Large fisheries science vessel delivered to Icelandic marine research body

Armon Shipyard in Spain has delivered a new fisheries research vessel to Iceland’s Marine and Freshwater Research Institute (MFRI).

The BV-classed, 69.8- by 13.2-metre (229- by 43.3-foot) Thorunn Thordardottir (Þórunn Þórðardóttir) was designed by Icelandic naval architecture firm Skipsayn in close collaboration with the MFRI under a €35 million (US$41 million) program with funding provided by the Icelandic Government. Skipasyn said construction of the vessel was completed within two and half years.

The designer added that Thorunn Thordardottir demonstrates excellent cost efficiency while offering broad research functionality and several innovative features that distinguish her from other ships in her class.

The newbuild honours the late Thorunn Thordardottir, a marine biologist and long-time MFRI department head who became known for her research on primary production of microalgae in Icelandic waters.

Thorunn Thordardottir is a multi-purpose research vessel designed for hydrographic and biological research, acoustic stock assessment and exploratory fishing in temperate and arctic waters. A dynamic positioning system allows the vessel to remain at station for research purposes (such as operation of a CTD rosette, launching an ROV, etc.) even under the combined motions of waves, wind, and currents.

Hull length and shape selection plus hydrodynamic optimisations

During the conceptual design of the vessel, it was decided that it would be more efficient to build a longer, lower and narrower vessel rather than a shorter, higher and wider one.

Skipasyn said the reasoning was that Icelandic research vessels typically sail between 20,000 and 30,000 nautical miles per year, and simulations and model tests showed that the narrower hull shape selected would save several hundred tons of fuel annually compared to the broader and shorter hull form that has become common in many recently built research vessels in neighbouring countries.

The final chosen beam of the vessel was 13.2 metres, allowing all required arrangements to be accommodated. Further hydrodynamic optimisation of the hull form resulted in an additional reduction of resistance by approximately 12 per cent.

Ensuring high bollard pull while minimising noise

Skipasyn said one of the major challenges in designing a research vessel, compared to a conventional fishing vessel, is meeting the strict noise requirements that apply to scientific operations.

Thorunn Thordardottir has a Kort nozzle providing about 30 per cent increase of bollard pull required for trawling. Skipasyn said the shipyard’s specialists were initially reluctant to approve the nozzle as they were concerned about potential noise transmission, but the end result was that the vessel met 100 per cent of acoustic requirements and can deliver 41 tons of bollard pull, exceeding what the shipyard was prepared to guarantee.

The vessel has a five-bladed propeller of four metres (13 feet) in diameter, housed in a nozzle, made by Balino, and is designed for zero to 125 rpm and optimised for low noise.

Skipasyn said it remained confident all along that, despite the nozzle, the vessel would meet all underwater noise limits defined by the International Council for the Exploration of the Sea. The company already had experience with this configuration on the freezer trawler Baldvin Njálsson, which it said comes very close to meeting the acoustic standards set for research vessels.

The vessel is driven by an electric motor, while the two main diesel engines produce electrical power for the propulsion system. The engines have been installed in such a way that noise and vibration transmission are kept to an absolute minimum.

Skipasyn said all of this is aimed at making the vessel as quiet as possible, since any noise can interfere with sensitive instruments such as echosounders, and high underwater noise levels can also disturb or scare away fish being studied.

A selective catalytic system installed on board for all the engines allows to minimise NOx emissions and ensure full compliance with IMO Tier III environmental standards.

The vessel has a 600kWh battery pack to cover power peaks and allow short electric-only operation.

The installed batteries act as an energy buffer. On a multi-purpose research vessel like this, high power can be needed for short periods, and with the batteries, there is no need to start an extra generator. The battery already supplies the needed power, and this capability also reduces wear on the engines by avoiding unnecessary startups.

Combination of capabilities

One notable feature of the vessel is that her stern is divided in two, with the trawl ramp entirely on the port side. The upper stern section of the hull is locally broadened to 14.4 metres (47.2 feet), providing the required space without affecting the vessel’s hydrodynamic performance and wave pattern.

MFRI wanted to achieve a spacious working deck for scientific operations and research equipment, while also having a capable trawler. The starboard section is therefore dedicated to scientific equipment and research work, while the port side boasts a conventional trawler layout.

The starboard side is fitted with a stern A-frame; a side gantry amidships with multiple research winches for deploying instruments over the side; various selections of winches, haulers and cranes; and a net drum.

The vessel is also equipped with a drop keel, which can be lowered four metres below the hull to reduce interference during surveys. The vessel can operate at full speed even with the keel lowered. When retracted, the keel reaches up to the bridge deck.

The vessel also features a fish hold that can accommodate up to 30 tons of catch. Skipasyn said that research vessels typically do not have a fish hold, as they are equipped with machinery that processes all catches for scientific purposes. In Iceland, however, the rule of full catch utilisation is followed whereby fish is cooled and delivered for further processing onshore.

Laboratories and accommodation

One of the most noticeable changes in the research facilities is that, instead of having separate laboratories for different types of projects, all research stations are now combined into a single general laboratory, with dedicated areas for acoustic measurements and deep-sea research. However, there will still be a separate space for the equipment used for underwater camera operations, and the vessel is fitted with launch and recovery systems for underwater cameras and similar research instruments.

Accommodation is meanwhile available for 13 crewmembers and 17 scientists in both single and double cabins, all with private bathrooms and showers. Other public spaces include a mess, day rooms, a gym, a conference room, and an office.

Thorunn Thordardottir replaces the older research vessel Bjarni Sæmundsson, which was commissioned in 1970 and has since been sold to new owners in Norway. As with her predecessor, the new vessel will be operated primarily in the North Atlantic.