While adequate the slower turning radius was improved after the war with the Top Stern rudder.
Here is some information that I hope helps you out.
http://www.perch-base.org/index_file...ub_Classes.pdf
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This one will open a PDF file that deals with certain aspects of submarine physics centered around torpedo avoidance of the submarine. Some information may be helpful in your search.
http://www.google.com/url?sa=t&rct=j...j1tCPOx9PriImg
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Here is a list of manuals and documentation:
http://www.hnsa.org/doc/index.htm#ss
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Submarine manual 1942:
http://www.hnsa.org/doc/s-boat/index.htm