We went for a adventure trip with my friend's 20' runabout... Hopping around waves and enjoying some waves... As we stopped to have lunch, I noticed a sailboat approaching us on a close haul... Though the wind was NNE, the current was SW... So they were sailing on our starboard but the current was pulling them towards us...
The question I want to ask is that how to warn some one that they may be pushed onto you by the current or winds if you don't know their call sign or if their
vhf is off?
I blew my whistle for one prolonged time for 4-5 times...
I'd love to think that they were aware of us, however, if they didn't was my reasoning...