The submarine shot at the British hospital ship, not a German vessel. Winters wanted to help the survivors, but the other three officers had a scuffle with him and killed him. The boat heads back to the original location. Brice shoots himself in the head. Odell, Claire, Wally and Stumbo (and perhaps a few others) survive and are rescued by a British vessel. The majority of the crew died when a spark ignited the hydrogen that had accumulated in the sub.