For realism, the RFB mod is the way to go. Refer to the "stickie" thread at the top of the page for info and D/L links. While there, you may as well look at RSRD, which is a complete overhaul of the campaign for fleet boats, and OM which is RSRD's counterpart for the U Boat campaign. Read the info for each mod as to install order, patches, and versions. You'll also be wanting this:
http://www.subsim.com/radioroom/show...=german+speech for your German language. Otherwise, your U Boat crew will be talking English.
I use all the mods I mentioned, plus PE mod for a realistic Pacific environment. All the mods are listed above in the stickies. I would'nt play the sim without them
