The annual flume tank trip to Hirtshals with Hampiðjan and its partner companies took place at the end of November. The tank is designed specifically to test scale model fishing gears, showing how these perform when towed and what effects variations in towing speed have. The flume tank is routinely used by fishing gear suppliers demonstrate their products and this is of particular interest to fishermen and fishing company staff responsible for selecting fishing gears.
The group that came to Hirtshals this time brought together pelagic and demersal skippers and mates, fishing gear producers and gear technologists. Attendance at the tank – as always – was good, with around 70 participants from around the world.
Both demersal and pelagic trawl gears were studied during the session. In terms of groundfish gear, Hampiðjan showed the latest versions of its popular trawls, including the Jagger 96 with expanded wing meshes and the H-Top 127 with a shortened belly and Magnet Compact netting used to replace Advant.
The pelagic trawls that attracted attention were the Gloria 2560 and Gloria 2720, which are intended for blue whiting and are due to be tried out at sea in the new year. These blue whiting trawls are now produced using Helix-Robus bars that are slimmer and lighter than the Helix rope that has been used up to now, and the Helix-Robus rope provides fishing gears with lower drag – with no loss of strength. The Helix-Robus material performed well during the last mackerel season and Hampiðjan is continuing the development of fishing gear with this rope. The mackerel trawls tested included the Gloria 1936 XW, which is a larger version of the well-known Gloria 1760 XW. Both of these trawls were also demonstrated in a Helix-Robus version that gives the fore section of the gear a 25% reduction in twine surface area that makes the gear lighter to tow.
Herring trawls were also on the agenda. The Gloria 2048 is a heavyweight design with three sweeplines that close off the sides of the swept area to increase herding effectiveness. The super-strong Gloria 1792 and Gloria 2048 Rockall trawls were also streamed in the tank, and these are gears that are optimised for the difficult conditions of fishing off the Rockall area. Participants were given the opportunity to request rigging alterations to see what differences these made to gear performance.
This flume tank trip also gave participants the opportunity to become familiar with the latest ground gear, the Injector Flow Gear that has been developed by Hampiðjan’s subsidiary Mørenot, and which is now subject to a patent application. Flow Gear is based on semi-circular plastic sections instead of the usual heavy rockhopper discs. The streamlined semi-circular profile reduces towing resistance and ground contact, which results in lower tensions and reduced fuel consumption. This gear configuration also contributes to better gear spread and gives the trawl more stability during a tow. Tests have shown that the water flow over the semi-circular sections increases the flow to the centre of the trawl, which herds fish more effectively into the gear and this results in better catch rates.
A comparison was shown of DynIce Data sounder cable against a steel cable during a tow, and the key difference is that DynIce Data is significantly lighter and has a tendency to rise, while steel cable sinks. DynIce Data helps lift the headline while steel cable adds weight to pull the headline down and under some circumstances can even spook fish if it lies too low. DynIce Data also has the advantage of maintaining a much higher position in the water when turning and can pass over the trawl doors if slack occurs. The comparison in the tank made this difference abundantly clear.
Hampiðjan’s collaborators took the opportunity to show their latest products, and Thyborøn Trawldoor put the emphasis on its Type 28 trawl doors that have already been successfully tested. The Thyborøn team also demonstrated their remote-controlled pelagic trawl doors that have performed exceptionally well, with around 30 pairs now in use around the world – including in Iceland. The design of the Thyborøn doors is protected by patents and are more robust than other controllable doors on the market.
Simberg presented its Simrad fishfinders and trawl sensor systems for both pelagic and demersal fishing. Key innovations are the Simrad TP60 trawl sensors that provide real-time gear positioning direct onto the sonar or plotter screen, and the Simrad SN50, a combined 160°sonar and 50kHz multi-beam sounder, which is a versatile fishfinder for demersal trawlers. Also on display were the Simrad FS80, a new trawl sonar due to arrive on the market in February as a replacement for the FS70 that has been in use for around twenty years, and the Simrad ST93 mk2, a low-frequency sonar working in the 14-22kHz range, which comes with a powerful transmitter and a more sensitive transducer. Finally, the latest software for Simrad’s ES80 echo sounder was discussed, and this brings in AI to analyse marks for species composition.
Visits to companies linked to the fishing sector is a regular feature of Hampiðjan’s tank trips. This time a visit was arranged to Skagen to see the new pelagic vessel Havfisk, currently under construction at the Karstensen shipyard. This visit to Skagen also took in a call at the magnificent new net loft at Cosmos Trawl, Hampiðjan’s Danish subsidiary, and this was formally taken into use in September this year.
The group spent three days in Hirtshals. Despite the packed schedule, there was plenty of opportunity for social time in the evenings. The flume tank trips are a great opportunity to meet fishing industry colleagues, to renew old connections and form new ones. At the end of the trip, the group travelled to Copenhagen for dinner with Hampiðjan, and many of those taking part took the opportunity to extent their stay with partners and spend a few days in the city just as it sports its Christmas lights.
Hampiðjan’s flume tank trips are an annual event and the next trip will be organised for around the same time next year.
