In the conclusion,the influence of turning is great for the ship of great tonnage,big turning radius and long turning period,which distance of the closest point of approach(?d???DCPA?) will be less than safe distance.

• 结论是大型船舶在变向避碰中；因吨位大、旋回半径大、旋回时间长；其避碰效果受旋回的影响较大；使实际最近距离小于安全距离.