Join Date: Aug 2014
Location: Bristol, RI
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Re: What does a centerboard do?
Some Lessons from Managing a Centerboard
See John Rousmaniere, The Annapolis Book of Seamanship, 4th ed., 2014, p.22. John talks about “the centerboard as a pivot point under a balance beam where the mainsail and jib push in opposite directions.” I like that concept with the centerboard providing upwind side force, and it helps me to visualize this. This helps me to balance my helm and point upwind. But how do I manage my centerboard as the wind pipes up? I know that your question is for the smaller boats but I did not find much guidance for this question on the larger boats. My centerboard is 6 ft. and keel draft with board up is 6.5 ft. so a heft 12.5 ft. down. Some lessons from my Sail & Power, USNA, 1967, and learned long ago on their racing Luders 44 yawls, I still use today:
1. When maneuvering, have the centerboard all the way down, otherwise she makes leeway (remember that pivot point discussed above)
2. Small boats – lower the centerboard to allow you to step up on it next to the keel to right a capsized boat (No, not much help to me on a Hinckley SW59)
3. Resistance to making leeway or lateral resistance - covered above
4. When running, the board is usually all the way up. When beating, it is all the way down. Note: I leave mine down in any wind above a light breeze until the wind is abaft the beam, and then start drawing it up gradually.
5. When jibing in a breeze the board should usually be about a quarter of the way down. Some good discussion around this one, but their (USNA) consensus was all the way down and the boat may trip on her centerboard, all the way up and she can slip to the side causing roll and yaw in heavier seas.
6. When reefing when the wind pipes up and on a beat or close reach, and heel becomes excessive for the boat (17 degrees is my magic number but boat specific) and the helm becomes heavy, the centerboard may be pulled partially up. (Note: I use 45 degrees and have my centerboard pendant marked so) to move your center of lateral resistance (CLR) back while topside you reef the main and then the jib, if required, to move your Total Lateral Resistance (TLR) forward. Note: That you are using both CLR and TCE to balance the boat to conditions.
7. In light air you will probably make better headway with the centerboard up if you have any keel at all on your boat as the board presents too much resistance to forward motion.
That is how we learned managing your centerboard at the academy on the small boats and applied it on the big boats. That was 45 years ago for me. There are some fine sailors on this forum. Maybe they have something more current than this? Well, I hope these old lessons from the “sunny swells of long ago” are helpful. They serve me well.