I am going write about the B-39 Soviet attack sub. It had 6 torpedo tubes on the front and 4 on the back. There were holes, called water tight bulkheads, to get to some different places on board. Some torpedo tubes were open so we took pictures of us in them and one had even had a torpedo in it. I also saw one that they recovered from the ocean that helped sink a big tanker from World War 1 or 2. It took two of them to sink it.