Handbook of the U-Boat commander
In German armed forces (Wehrmacht) there were a whole range of the regulations (Dienstvorschriften). Depending on the forces (army, air force, navy), these regulations were divided into so called H.Dv. (Heer Dienstvorschriften), L.Dv. (Luftwaffe Dienstvorschriften) and M.Dv. (Marine Dienstvorschriften). They contained the field regulations, descriptions of the weapon systems, operating manuals of the communication systems and so on. The set of these regulations can be viewed on this website: http://www.superborg.de/
The text below is the translation of the parts of German handbook for U-Boat commanders - M.Dv.906 Handbuch für U-Bootskommandanten - related directly with the torpedo attacks. Here are available the photos of the original document, here is the German version of the corresponding parts converted into html format.
Note: the translation based on the direct wartime translation by the U.S. Navy, which is available in the hard-copy form or on the Internet (i.e. here). The original translation contains many inaccuracies and thus (with a wider knowledge of the topic) was corrected.