Originally Posted by alystra
In answer your question, I think the procedure would be ".... This is [boat name] Mobile." . Whenever we heard that, we would always take into account that the caller may be ashore.
That is what I would do. I've heard RNLI do likewise after they have landed crew ashore to go and find an injured walker.
If you wanted to be "perfect" then I think a "mayday relay" rather than a standard mayday call would help the recipient understand that you were an observer rather than active participant. At the end of the day though any call is better than no call and the CG are quite good at extracting the information they need.