Notice:
The advice given on this site is based upon individual or quoted experience, yours may differ.
The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.
A consistent 90 degrees true is pretty good. Are you measuring that with the compass or the GPS headings? The compass shows you where the boat is pointed--the GPS tells you where it's actually going ("course over ground"), including leeway (side-slip) and currents if any. (Tacking up-current will look worse on the GPS, and down-current better.) As the wind picks up above 10, your speed will both reduce leeway and help pointing. If that gets your COG angle below 90, I'll be impressed!
Dave Bristle Association "Port Captain" for Mystic/Stonington CT PO of 1985 C-25 SR/FK #5032 Passage, USCG "sixpack" (expired), Now on Eastern 27 $+!nkp*+ Sarge
Hmmm... I had about 8 knots of wind, both the GPS and the compass were agreeing on the 90. I was by the dam on the reservoir, so not likely to be too much current down there. By pure luck, I was literally on a due west course and tacking to a due south course... wind out of the SW obviously. BUT, I didn't really look at COG. I was on a due south heading but that doesn't mean I wasn't slipping. I'll check the track (not sure I had it on.)
The GPS heading is COG. A C-250 WB (or WK) is not a Melges 24 or even a J-24. If you can hold 45 degrees COG off the true wind, translating to a 90-degree true tacking angle, in 10 or fewer knots, I'd say you're doing all that boat, with good sails, can be expected of. You've got it figured out! Good work!
On the other hand, in a race, you might find your "velocity made good" (VMG) to a windward mark in that light-to-moderate air is better by falling off just a little to gain speed and, with it, to reduce leeway. The way to measure that is to set a waypoint up-wind (far beyond your objective) and set your GPS to show the VMG to that point--then set a course and trim to maximize VMG. The distant waypoint reduces the VMG error that can increase as you get closer to the real objective (like a race mark) due to the increasing angle to it as you get closer. VMG is the true objective both for tacking upwind and for jibing downwind.
Dave Bristle Association "Port Captain" for Mystic/Stonington CT PO of 1985 C-25 SR/FK #5032 Passage, USCG "sixpack" (expired), Now on Eastern 27 $+!nkp*+ Sarge
Thanks Dave. I will give that some effort, because I'd like to get a better sense for VMG. I was pretty surprised to get a good 90 degree tack. The other factor is that I'm on a reservoir at 5,500 feet... and the winds are shifty. I will tack to 90+... and have to keep going... and end up on 180 degree tacks. Some days I can tack all the way up the lake... then the wind shifts up the canyon and I tack all he way back down. Like the old day... uphill both ways :)
Notice: The advice given on this site is based upon individual or quoted experience, yours may differ. The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.