I was taught that a "securite'" call was for things of concern to all in the water
, for instance, a partially submerged obstacle.
"Pan Pan" I was taught was to alert boats and ships in the vicinity that I was in distress
and that it might become serious enough for a "Mayday" call. Ihave heard those several times and have heard responses from other boats that they will move in that direction and stand by. Don't know what else happened as we had to switch to the bridge channel. We were not near the boat in distress
I called what amounted to a "pan pan" although I didn't use those words since I was calling Boat US. Eckerd College's Search and Rescue
program (EC-SAR) heard me call Boat US. We didn't have a cell phone
on the boat, so they switched us to 68, and EC-SAR continued to listen, heard the details, thought they might be of additional help and came to us quite rapidly.
I was surprised and asked them why they had come, and they said they had heard the decription of the boat (very small for the seas we were in) and heard that someone would have to go to the bow to catcha towline. They came in case someone fell into the water.
They stayed off my bow, out of the way but ready to act for 20 min. or so until Boat US was there, watched me crawl to the bow and manage to catch the towline, made sure we were under safe control, then waved good bye and raced off to help someone else.
I would have caused our situation a Pan-Pan as it was not *yet* life threatening, but it did have the potential to become so. Two other boats were staying near us for the same reason. So we didn't actually have to use the words "pan-pan," but I think it a good idea because other boats' radios (and yours, perhaps) may get a little garbled in tranmission. If you say "Pan Pan," they know that you consider your situation serious.
I also called out a securite' once in the ICW
for a large log that was nearly submerged. The Coast Guard called back, got the lat and long, and retrieved it, and thanked us for the call. Someone on my boat said "Oh don't do that -- someone else will or already has," but ... no one else had.