U-93 bought it in June of 43
http://www.subsim.com/radioroom/showthread.php?t=203628
sometimes i run a few concurrent careers... some with the same flotilla, some in other flotillas, U-225 held out until December 1943. My only remaining 1943 career is currently on shore leave and will probably head back out late December 43 or Early January 44 on the next patrol.
I try to keep to some degree of historical accuracy, there were a lot of boats being sunk and scuttled from may 43 onwards.
If i am deep (220 meters and deeper) and im taking a licking and have overwhelming damage or it becomes apparent i cannot repair it an escape, i surface - end career and use SH3 Commander to switch to "Surrendered at sea"
But only if i manage to surface.
There have been many occasions where i have been crushed by sea pressure / depth charges
one particularly memorable occasion i struck bottom in a VIIC at nearly 400 meters with moderate flooding. It was very much like Das Boot.
The Depth charges cannot reach that deep in SH3 and the escorts finally left. I was on the sea floor pumping out water and repairing systems for quite a while before blowing ballast - reaching the surface and heading back to port.
fact is on high realism with GWX 3 - you really do have about a 75-80% chance of not coming back from a patrol after mid 1943... thats pretty real to life odds for a u-boat crew of that stage of the war