A question about the German Grid system.
 

The German system of indentifying the sea areas with a grid system starts with the alpha identification, then it is divided into numerical squares. But somewhere I can remember seeing these smaller squares being further divided,into, I think, sub alpha idents. So one might have a location 'BF32ag'. Can any one confirm this? It would seem to make sense especially when trying to locate a supply ship.

That is basically correct. I can remember something like that from my reading although I believe the last 2 coordinates were numerical.
I'm not positive but I think there was a base 10 system in place for this......

It's 2 letters then 4 numbers

This page from Uboat.net explains it:
http://uboat.net/maps/grid.html

Thank you stew278,

Just what I wanted.

I found this while Subsim was down.:know:

http://www.geocities.com/germangrid/eindex.html

In a funny turn of events my radio operator informed the BdU that we do not have the top secret map decoder on board. They send us the coordinates via lat and longitude now. Never seen it happen before, just this profile in 1940.