7 September 1939, 1st flotilla out of Kiel, 84% realism.
Got to the patrol area, but was immediately jumped on by a destroyer in the dark. My boat took a battering from the depth charges, and was forced to the surface. Just as I was looking for the "Ok, ok, we'll come quietly" hot key, the sub got rammed and sank without so much as scratching the paint on a merchantman.
Well, could have been even worse - it came within an emergency reverse of ending ten minutes out of Kiel, when a mix-up with a plotted course almost had me crashing into the first bridge on the canal. I could just see the headlines: "U-boat lost with all hands in Kiel canal".
Looks like I need a bit more practice with this...