Give us fog tips and tell your best harrowing fog stories.
Fog tips: Have, understand, practice, and use RADAR.
AIS is a nice add-on, but not all boats run it.
Slow down and try to run within your visibility range - not always possible.
Run your fog horn.
If you can avoid it, stay out of the fog.
Running up the Newfoundland coast, there were two notable events. The first one was the middle of the night - don't know if it was fog or just totally overcast with very low hanging clouds, but you couldn't see anything. We were several miles off-shore and could see we were coming up to a cluster of fishing vessels. I don't recall how many, about a dozen. Most of them were running AIS but several of them were not. They were all clearly fishing in this one region spread across several miles but since there were so many of them, it was like a huge blockade. To go outside of them would have meant a couple of hours out of our way so we decided to go through the bunch, a bit more off-shore from what appeared to be the center of the group. The fishing boat there were running in a large diameter circular pattern, very slowly. It was really interesting to see the lag in position from the AIS signal and the RADAR position. We relied on the RADAR signal for better positional accuracy. No close calls, but quite a learning experience comparing the AIS signal to the RADAR signal.
The second event, also no close call, but really interesting, at least to me. We were about a day out of St. Johns, Newfoundland, our final destination for that leg. We were several miles off-shore, it was early in the morning and the fog had rolled into the coastal region of Newfoundland. We were just outside the fog limit. So we were sailing in this beautiful bright sunny day but to our port side about 100 yards away was a "wall" of fog. It was stunningly beautiful! I didn't have my RADAR on as I didn't feel I needed it in the bright daylight as it takes power to run. We are sailing along and then hear a fog horn coming out of the fog, north of us. It was the kind of fog horn that large ships have - you know the sound.
I powered up the RADAR and while waiting for it to come alive, I decided even though I'm not in fog, running my fog horn might be a very good idea. I had no idea what that boat was or where it was heading, it was not running AIS. Once the RADAR came on-line, I could "see" a huge ship off my port side with apparent rumbe line parallel to mine, off my port side. We kept a close watch on that ship and kept running our fog horn until well past each other. We finally passed each other at maybe 1/4 of a mile off our port sides. It was amazing that at no point could we see that ship, not even a shadow, as we passed port to port - it was running inside that fog bank.
dj