Roger that. It would be interesting to hear from the Nav gang on a sub... though... I suspect it is closer to surface nav than we might have guessed. Charts is charts... :-)
I give the Captain and Crew a BZ for getting SF under control and returning to port. I know the Navy is unforgiving in these incidents. I read the mixed message in the Admiral's remarks in this thread.
I've friends who are former submariners but not NAV who tell me there's a preprogrammed course plot and redundant systems. There are changes in the sea floor over time; if that chart was from 1960 and that sea mount grew 10 feet....well, go figure.
Good chat, Ramius. Let's see what we can find out.