Major Milestone Achieved For Controllable Trawl Doors

One Step Closer to Controlling the Trawl Doors Remotely

Notus and Polar of Iceland have partnered to develop controllable trawl doors that are wirelessly controlled from the ship. A major milestone has been achieved in the project as controllable trawl doors were used in active fishing operations onboard an Icelandic trawler.

The doors are constructed from aerodynamic shaped wings. By moving the door wings, water flow can be changed which allows control over: spreading force, trawl depth and trawl positionthe FV Vestmannaey tested the Poseidon 4.0 metres controllable doors for bottom fishing and to control the doors’ distance from bottom. The doors were controlled by the Notus remote. Notus also supplied sensors to monitor warp length, spread and door angle.

Adjustments in the wings had a direct impact on the trawl. The left graphic below shows the door heeling outward at -30⁰ and doors spreading 30 Fa. Commands were sent to the door to alter the position of the wings. The right graphic clearly indicates the difference from altering the wing’s position, the door stood up an additional 19⁰. As a result, the spread increased 23% to 37 Fa.

Skipper Birgir Thor Sverrisson of the FV Vestmannaey (right) was pleased with the doors. “We changed position from high roll, increased spread, reduced spread and rolled the doors out to use less trawl warps. It looks very promising”.

The next step is to take the same 4.0 metres doors for a test trip fishing mackerel this summer