wondered this also.
Was coming out of Lorient on 1x TC (which does my head in... lets not go there!) - nipped downstairs to wash the dishes whilst it took 20mins to exit the harbour and i popped back to see warnings of flooding in the bow. Thought it was aircraft perhaps but they would have to be suicidal to attack me that close to a port. Sure enough, i nipped to external cam and found about 1km back a type VIIC at an odd angle. Apparantly we were on a colision course
Let's just say that no beers were bought for the kaelen upon return to Lorient! And the W/O was made to waterski off the stern on his ass Bernard style as punishment.