When practice dummy torpedoes were fired, it was necessary to recover them. This could only be done if the seas were calm. Despite the tendency of submarines to roll, the parts of a crane were stowed under the deck, and these would be assembled. A swimmer would try to fasten a line to the nose of the torpedo, and then it would be hauled aboard with the crane. The forward and after torpedo rooms had hatches equipped with slides so that the torpedoes could be lowered into the torpedo room.