Have a question about CG (center of gravity) and CB (center of buoyancy). I've been reading BCU's new (2002) edition of "Canoe and Kayak Handbook," and I refer you to an illustration on page 25. Here we see three paddlers in various situations: A) paddler has CG over his CB; he is sitting upright in a flat boat (no waves). B.) Paddler is leaning boat to left, body titled (to the right) over his boat so his CG is again over his CB; his paddle and right arm is extended over the right side of his boat. Both A and B are termed "stable situations." In situation C the paddler is leaning into a large wave (well over his head). His paddle is extended into the wave (to his left again), but his boat is not leaned. His CB is way to the left side of his boat, but his CG is still centered over the CB; his head is over the gunwale, his body leaned just enough to get CG over CB. The text on the page 25 and the next page reads, "If the CG's vertical alignment falls far enough outside the CB you will capsize unless you support (provide additional support upwards) on a paddle stroke." And further on, "If you look at Fig. 2.6c you will see a paddler about to capsize." I am not sure I understand this. The paddler in Fig. 2.6c still has his CG over his CB, thus (possibly) contradicting the text. I now speak from personal experience. This winter (in rather chilly 35 degree ocean paddling) I leaned into a breaking wave near an offshore reef. I tried keeping my CG over the leaning side and my CB, extended my paddle, and the wave broke on me, apparently catching my boat's edge. I went over. Fortunately I was able to roll up, took a breath and another wave caught me off guard. I flipped again, rolled up and got the devil away from the reef. Will you offer me your insights? I am not sure what I may have done (and I don't expect perfect clairvoyance from anybody, since this is not on film ;) I would like to mirror Wayne Horodowicz's techniques for broaching wave action, but I'm still a learner of the surf stuff. I am a fairly good paddler and can handle reasonably energetic seas, but in the breaking stuff I frankly suck. Thanks for your instruction and thoughts! Tom *************************************************************************** PaddleWise Paddling Mailing List - Any opinions or suggestions expressed here are solely those of the writer(s). You must assume the entire responsibility for reliance upon them. All postings copyright the author. Submissions: PaddleWise_at_PaddleWise.net Subscriptions: PaddleWise-request_at_PaddleWise.net Website: http://www.paddlewise.net/ ***************************************************************************
Tom, To paraphrase what Scott said, "Don't over analyze this." It's really a question of feel. I very rarely get tumbled on landings and almost all of mine are done broached. What I do is *lean* well into the wave and use either a low or high brace depending on the size of the wave. As soon as you feel the wave easing up, start bringing the boat back underneath you. If you take the time to stop and figure out where the CB and CG are, you will be underwater. There is no time for thought in the surf zone, your actions have to be automatic. The technique that Wayne uses to teach side surfing while in flat water works. I didn't believe that I could move my boat forward and back while side surfing a wave and Wayne gave me some exercises to try while using his sling in flat-water. Not only did it work in the flat-water, but I now regularly use it in the surf zone. Remember though, you will swim a lot while learning the techniques - but hey, kayaking is a wet sport. Steve Holtzman *************************************************************************** PaddleWise Paddling Mailing List - Any opinions or suggestions expressed here are solely those of the writer(s). You must assume the entire responsibility for reliance upon them. All postings copyright the author. Submissions: PaddleWise_at_PaddleWise.net Subscriptions: PaddleWise-request_at_PaddleWise.net Website: http://www.paddlewise.net/ ***************************************************************************
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