My partner in the boat and math genius pal Malcolm has been trying to wrap his head around the polar charts and optimum wind angles and has hit a wall. Since I can’t articulate to him why the angle is what it is (due to Apparent wind) I’m posting his email to me up here in the hopes that one of you geniuses know the answer and can help.
This is probably driving him crazy so the sooner we get an answer the sooner he can get back to sleep at night.
Read:
I keep looking at the Polars for our boat and thinking I’m missing something. The high end and low end of the wind ranges seem incorrect, at 6kts (True Wind Speed) they say we should be sailing 85 degrees, that’s not down wind. In 20kts they say sail 114 degrees.
I was wondering do you know anyone who we can ask how to read these things. The chart is in Apparent Wind, so unless I’m missing something, this tells me to sail in 6kts of breeze 180-85 degrees or 95 degrees off the wind, in 20kts using the same logic 180-114 we would be sailing 66 degrees off the wind.
To further the point
6kts wind at 180 degrees – preferred port course 275, starboard course 85 degrees
20 kts wind at 180 degrees – preferred port course 246, starboard course 114 degrees
If you were to plot this as they have on the polar you wonder how the added VMG does you any good because you’re sailing the opposite direction of the mark in 6kts, not much better in 20.
I’m doing something wrong, but, I don’t know who to ask. I’ve done a bunch of reading but, I’m not getting how to use this information when the polars say such weird things.