That looks very cool Mike. I'll have to test it out, especially the auto-polars function, so thanks for the link.
About your plot, were you going upwind against the current? Everybody say you should get 45deg angles upwind depending on conditions, but your plot show about the same angles as we got when we measured last year.
Nice lift at the top of the screen.
I was going upwind on the red colored trace (indicating lower speeds) from right to left in the picture. You can see a lift on the red port tack lay line (wind coming from left side at ~270 deg). Breeze was building slightly and shifty during this tack, swell basically head on. My two first tacks show about a 90 degree angle, so I was doing about 45 degree off TW. The third/last tack I footed off and prepped for beam reaching, so the tack angle looks bad. The sharp turn is the full bear away & gybe. I'm then beam reaching, jib & main alone. I'm able to get some surface action sustainng for 15+ seconds regularly and it seems to impact the polar significantly. On the next leg following a gybe to starboard, I can no longer surf and the wind lifts...exaggerated no doubt by the lower speed since not surfing. Gybe angles look pretty shabby...but I think that's an effect of the small jib...can't sail well anymore with the AW off the beam...got to go higher. Gybe angles with spin look more like 90 degrees, but this is in only 5-7 kts true...we do less than 90 in better air.
Mike.
