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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.


Some reflections on this after last year's Nationals at SDYC. 45 degrees is an over-simplification:

The smooth polars I've seen for the Tornado http://tinyurl.com/2ltfj4 put max VMG at 50 degrees, but anything between 45 and 55 is very close. .


Since those plots show boat speed, not VMG, are you doing the calculation to arrive at 50 deg. for max VMG?
The GPSAR software can show both speed & VMG on one plot (solid lines for speed, dotted for VMG)...but to be accurate you need to put in the true wind direction & velocity.

Mike Dobbs
Tornado CAN 99 "Full Tilt"