Tryed without map update, but nobody warn me for any ship while travelling the long-distances. Just one time i was patrolling in the patrol area with 4000x faster time. I just passed near a well-protected convoy. And they take me down 4000x more faster than normal. My sonar guy better to warn me for any contact at least next time. Else its not fun to watch over sea to much. It makes me more tired than i am. Its just a game we arent real sub captains anyway.