>>63941502
If a 50-ton sperm whale rams the outer hull of a submarine several times in the same place, perhaps at greater depths where the hull is already under pressure, I think it is quite possible that a leak could occur. This could pose a danger to single-hulled boats if they do not close the bulkheads in time. Russian and Chinese nuclear submarines are built with a double-hull design. So I don't believe a sperm whale could cause enough damage to sink a submarine.