Experiment of Large-mesh Otter Board Trawl Modification

The modification of otter board trawl,of which the former mesh size was enlarged from 140.0mm to 400.0mm,2000.0mm and 8000.0mm respectively,was reported in this paper.As a result of the modification,the circumference of net mouth increased from 72.8m to 88.0m,148.0 m and 300.0m accordingly,the trawling speed climbed from 3 knots to 4~5 knots with the same main engine power of fishing boat,and the vertical opening of net mouth gained 2~5 meters.The fishing efficiency improves very much.