Jim,

What I have done is set a GPS mark miles to windward and track VMG. The problem with pinging the windward mark is as you get closer to the mark, the VMG will be distorted. On the big boat, we were able to use the apparent wind angle and quickly discover the best VMG. On the hard drive, I do have a polar diagram for the Tornado. The problem with our Nacras, is they didn't attract the techy sailors that understood and dedicated the time to assemble polars. With a lot of data and time, you could assemble some polars...