Hi All
I started of trying to understand why the sail is almost always close hauled no matter what direction one is sailing relative to the true wind. Obviously this led to discussions on apparent wind direction and speed. So I think I have got my head around most of this but there is one point I would like clarification on.

Is there a formula or at least a rule of thumb (other than feel while your sailing) to find the best point of sail for a given ratio of boat speed vs true wind speed?

I.E. if the best point of sail is 90deg off the wind at a ratio of 1:1 then what would it be at 2:1, 3:1, 4:1, 5:1

I am assuming these figures will plot some sort of curve falling away from the true wind direction and I know you can feel the right point when you’re out there sailing but I’m looking for a rule of thumb that will help me visualize what’s going on?