New netting from Hampiðjan aimed at the market for trawl gear offers a host of advantages, and reports from trawler skippers who have been testing the new Advant netting have been positive.
Bjarni Hjálmarsson who skippers factory trawler Blængur said that he has been testing a trawl made in the new netting since June, and is “delighted with the gear.”
“We’re fishing for mostly Greenland halibut and saithe now we’re into autumn, and it fishes well on both – and especially on saithe,” he said.
“We estimate this trawl is around 10% heavier to tow, but it is larger with a 54% longer footrope and we haven’t seen any damage yet. Apart from some repairs to the lower wings where it gets chafed on the deck or on the seabed, it has been maintenance-free. We’ve used it in every kind of weather and on everything from flat muddy grounds to rocky areas and steep banks. This trawl sits well and tows beautifully, and even when it has been collapsed, we’ve never had any rocks in the codend, just some sand occasionally.”
The key to the relatively low towing resistance for this larger trawl is Hampiðjan’s Advant netting, which reduces the trawl’s overall resistance, balancing against the heavier footrope – a 7.50 tonne rockhopper compared to the previous trawl’s 5.10 tonne footrope.
Advant netting has been developed to retain stiffness and to resist abrasion, taking full advantage of the properties of Dyneema fibres used in its production but while also making this new netting available at a price that is lower than that of netting made in pure Dyneema.
“We set out to maximise the stiffness of the netting and abrasion resistance, as the usual Dyneema netting available on the market quickly lose that initial stiffness with regular use, making them less easy to handle on a trawler’s deck,” Hampiðjan’s Guðmundur Gunnarsson said.
“Advant netting is made with a heavy PE core jacketed in a braided cover to maximise the stiffness. This is boosted by a new impregnation method which is also extremely durable and is not susceptible to being washed out. Advant netting has a significantly higher strength to diameter ration than PE netting and makes possible a reduction in twine surface area with 40% less towing resistance.”
The netting is manufactured with double knots to minimise mesh distortion and its elongation at breaking point is only 5%.
“The combination of materials used in Advant netting and the design mean that it’s considerably lower in price than conventional Dyneema netting. So this offers three advantages; lower cost that Dyneema, lower towing resistance than PE and a longer working lifetime,” he said, commenting that the new netting has been tested on a few selected trawlers, including Síldarvinnslan’s Blængur (ex-Freri) which for the last few months has been trialling an H-Toppur trawl made in Advant netting by Hampiðjan’s partner company Fjarðarnet in Akureyri.
Replacing the usual PE netting with Advant allowed Fjarðarnet designer Hermann Guðmundsson to increase the size of Blængur’s trawl, stretching the footrope length by 54%. The original 115m Toppur trawl was rigged on a 26 metre rockhopper, while the new 127m H-Toppur trawl Blængur has been testing has a 40.80 metre rockhopper and a 10% greater fishing circle, and giving it a headline height of between seven and nine metres, while the twine surface area in the trawl’s forward section is 36% less than that of the 115m Toppur.
“We had this trawl new on board after the Seamen’s Day stopover in June, so we have been using it for a five months now and we haven’t used any other trawl in that time,” skipper Bjarni Hjálmarsson said.
A haul of saithe taken board. All three codend sensors triggered. Skipper Bjarni Hjálmarsson said the 127m H-Topper trawl fishes well on all species, and is particularly effective on saithe.
The new trawl is around 10% heavier to tow than the older trawl, requiring a 50% pitch compared to the old trawl’s 45%. Blængur tows the Advant trawl with around 12-13 tonnes of tension on the warps, which is well within its 8 tonne bollard pull.
“We are fishing with a pair of 4400kg, 8.50m2 Thyborøn semi-pelagic doors, 165 metres of sweepline made up of 110 metres of single and 55 metres of double sweepline, which gives us a doors spread of between 165 and 185 metres. The doors are kept between four and ten metres off the bottom and we can easily manage how well the trawl maintains ground contact and we have long given up using the end weights at the sweepline ends.”
He commented that the 2mm Advant netting has replaced the 4mm PE netting in the old trawl and the new material has performed well.
“We haven’t seen any mesh distortion and the knots are stable. In terms of fishing we have been mainly on our own this summer so we can’t easily compare against other trawlers. But from the few occasions we’ve had another trawler near us, it seems that we’ve been doing better. The H-Toppur fishes outstandingly well on all species, but especially on saithe and we see the fish passing the headline sounder and making their way quickly back to the codend.”