Joe - the real question is did I know where I was once we hit the bars in Hong Kong!
Actually, coming to periscope depth as we approached Hong Kong was one of the most harrowing experiences I had as officer of the deck. We cleared baffles and came to periscope depth in the middle of a fishing fleet with hundreds of junks drifting about. None had their engine on so we couldn't hear them. It was only by shear luck we didn't hit any before the periscope cleared the water.
Once in Hong Kong, we were definitely on the surface!