There were definetly several standard zig zag patterns in Real life - unlike the random patterns that we see in SH3.
I've been trying to obtain this info myself, and some good fellows on uboat.net have pointed me in the right direction: The National Archives. Here are the docs that you should be looking for (perhaps there are more?)
http://www.nationalarchives.gov.uk/c...354705&CATLN=7
http://www.nationalarchives.gov.uk/c...054565&CATLN=6
http://www.nationalarchives.gov.uk/c...484272&CATLN=6
http://www.nationalarchives.gov.uk/c...484284&CATLN=6
As far as I can see, one can get the files scanned or copied by the archives, but this costs money ... too much for my finances. On the other hand, by visiting the archives (and ordering this in advance) you can get them for free.
Hope this helps.
Dan