Bison trawl door designer John Ashworth says he has sorted out the problems some skippers have experienced when using the doors with twin rig gear by using just a single backstrop chain.
He said four twin riggers had run into difficulties during the past year, with others experiencing problems of varying degrees.
Now, thanks to information from many skippers and crews the firm has been able to identify the problem and more importantly why it was happening.
Skippers had found that the doors were moving in and out when towing, which was due to the different drag loads imposed by twin-rig gear compared with single rig trawls.
John
