[seafarer]

Remember that "silent running" does not mean totally silent. It just means you are as quiet as you can make the boat, but you are still making noise. That noise can and will be heard by escorts, especially if you are sitting so shallow.

If your plotting is good, go silent running, but dive to 200-300 feet. Sneak into firing range rigged silent, slow, and deeeeep. Use your passive sonar to listen to the approaching ships. Judge when to come to periscope depth (use the "P" key on the keyboard) to make your attack. If the convoy is more then 2 rows wide, I try to judge it to come up in between rows of ships, then I can quickly target with both fore and aft tubes, then plunge deep again once the fish are out of the tubes (and turn to run down the length of the convoy - harder for the escorts to make attack runs on you if they have to dodge the mess of ships overhead.