Why Can’t I Bear Away From the Wind?

There are few “universals” in the sailing world, however, one thing that comes close is the tendency of new sailors to over trim sails.  There are a number of results to over trimmed sails.  For example, sail shape isn’t as effective, causing the boat to slow down and heal more, which by the way results in an even great loss of speed.  In other words, a boat with properly trimmed sails goes faster.  Today’s discussion focus’s on another aspect of over trimming, the creation and/or increase of weather helm.

Weather helm is the tendency of the boat to turn towards the wind, and is a good thing.  Boat builders design in a small amount of weather helm to give the helmsperson some “feel” of what is happening and for safety.  If you let go of the wheel the boat should turn to windward and come to a stop.  Too much weather helm is not good, making the boat difficult to steer.  To more fully understand why this is requires a discussion of Center of Effort and Center of Lateral Resistance.

Center of Lateral Resistance (CLR) is the “balance point” of the boat.  If you push forward of the CLR the bow moves away.  If you push aft of the CLR the stern moves away.  Visualize a teeter totter.  The pivot point in the center is the CLR.  More weight (effort) on one end results in that end going down.  The Center of Effort (CE) is like the weight pushing.  CLR is moved by shifting weight forward or aft, or by healing more or less.  CE is more easily controlled.   Each sail has it’s own CE, located at the geometric center of the sail.  The overall CE for the sail plan moves along a line drawn between the CE of the main and the CE of the jib.

Here is a real life example of how CLR and CE interact with each other.  You are sailing along nicely in 10 knots.  The CLR is a bit forward of the CE (by design) allowing you to feel the rudder, but not feeling like the boat wants to turn into the wind.  As the wind builds the boat heals more, moving the CLR forward.  The result is more “push” from the wind, further aft of that CLR pivot point.  The boat now wants to force itself into the wind.  If you have ever wondered what a traveler does … “dropping” it down moves the CE forward, closer to the CLR allowing you to regain control.  If that’s not enough, putting in a reef moves the CE forward even more.

Now comes the fun part!  The trim relationship between the main and the jib can actually move the CE whichever direction you want, forward or aft.  Properly trimmed, the boat goes pretty much in a straight line.  Trim the main and ease the jib and the CE moves aft, causing the boat to head up.  Ease the main and trim the jib to move the CE forward.  Move the CE far enough forward and the boat will bear away.  Give it a try.  It is amazing how much steering control you have using just the trim of the sails.

It seems like we’ve totally skipped the question in the title of this tip.  Why can’t I bear away from the wind?  That was a question asked of me recently by a club member.  By now you may have figured out the answer.  The CE is too far back, creating so much weather helm that you can not overcome it with the rudder.  The fastest and easiest solution … ease the main.  The boat will turn downwind easily, and the sails will be better trimmed for the new point of sail.

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