Hi SC,

if you want to calibrate against other boats to confirm your model, here are my numbers:
Dart 18 cat double handed, strong wind, flat water: 17.3kts
Tornado classic double handed, strong wind, waves: 17.9kts
Javelin 16 with hooter, medium wind, flat water: 16.5kts
all numbers are over a time interval of 10s and there was no significant current. These are top speeds of course.
For the windward legs, I have to dig in the data. Let me know if you need speed and vmg, and I will dig them out.

Cheers,

Klaus