On the second night we approached the u-boat stream.

在第二天的夜里，我们驶近德国潜艇的出没路线。

The next day the u-boat was towed by a trawler to iceland.

于是在第二天，那艘潜艇被一艘渔船拖曳到冰岛。

The lethal power of the air in u-boat warfare was yet to come .

在潜艇战中，空军的致敌于死命的威力还没有发挥出来。

Here is the SMS Vulkan, sub tender for the North Sea U-boat fleet.

这是一艘“维路卡”号补给舰，为北海U艇部队所有。

No more do we have to accept a generic start date for a certain U-boat .

我们也不必须为某种潜水艇接受一般的开始日期。