For successful towing a trawl net, one of the problem is to insure the spreading of the otter board, therefore, it is necessary to consider the behavior of the warp vibration while in operation. The warp, when the otter board attach the bottom, the vibration of warp become trainsent vibration, the stress in the warp may be three times of usually steady state, and the warp may be broken according the roughness of the bottom. Several distinct factors may contribute to the tension of warp. First of the factor is the drag of the warp and trawl net, the second factor is the weight of the warp and trawl net, the third is the geometry of the bottom.
This paper developed a brief therotic compurgation to analysis the dynamic behavior of towing warp system. And the therotic result were compare to the full scale experiment result by the R/V Hai-Kung in 1984, we found both two results are quite agreement.
Key words：Trawler, Warps shock vibration, Accident harm in trawling