As well as its Storm and Tornado trawl door designs, Vónin and its Danish design partner have also developed the Flyer, a lift generating device that takes as much space as four floats in a trawl’s headline, but provides a significantly greater amount of lift.
The Flyer is shackled to the headline and unlike conventional kites that can require careful adjustment, it is self-stabilising once in position. Like a kite, the amount of lift is relative to the towing speed, generating 90kg of lift at a 2.50 knot speed, while those four conventional floats provide 30kg of buoyancy.
‘At 3 knots, the lift generated is 120kg, at 3.50 knots it’s 155kg and it rises to 185kg at a four-knot towing speed,’ said Vónin’s Bogi Nón, adding that the Flyer is envisaged for both demersal and pelagic gears.
The Flyer is moulded in a single piece from polyurethane, a material that has flexibility while retaining the toughness needed for the unavoidable rough treatment on a trawler’s deck as the gear is hauled and shot.
‘The prototype looks very promising so far and we’ll be testing this shortly on commercial bottom trawls to get some feedback on how it performs under real conditions,’ he said.
