Pinch or fall off, an easy answer?

[Andy]

Is there a "rule of thumb/usually it is best" answer to; If you fall off the wind "X" degrees and gain X.x knots it is faster to sail the longer distance. Example: 10 degrees off the direct course means 1/2 knot in speed. I suppose the distance to the destination is also of importance. Then we may be getting in to frequency of tacking. Note: I am a cruiser not a racer so saving quarter hours not quarter seconds is the goal here. Thanks.Andy"Baroque"

 

[Ranger Paul18580]

Pinch or Fall Off - Geometry

This is a pretty simple geometry problem but it requires too many parameters to be easily solveable (current boat speed, true angle to the wind, etc.). This is doable but there is an easier way. I used the VMG reading on my handheld GPS. I entered a waypoint directly upwind then tacked back and forth measuring my VMG as I pinched as high as I could then gradually fell off. I found that with my boat, falling off the wind between 5 and 10 degrees increased my VMG. Of course sail trim comes into the picture. I did this quite recently. My next task is to do the same thing under various wind conditions then mark my jib sheet for the "optimum" jib settings under light, medium and heavy winds. The main setting then follows the jib setting and angle of attack of course.