If I remember rightly that is one thing that annoyed me with OM! The dive times were unrealistically way too low, something like a minute and a half!
@ Ducimus, from what I have read, and so far about 3 dozen U-boat books, the Atlantic was so murky that the boats were not visible below the surface, have never read any being attacked that way, only if the scope or snorkel was detected, not to say they weren't, just never read it.
