{"id":12819,"date":"2010-08-29T13:42:32","date_gmt":"2010-08-29T18:42:32","guid":{"rendered":"https:\/\/setsail.com\/?p=12819"},"modified":"2010-08-29T13:42:36","modified_gmt":"2010-08-29T18:42:36","slug":"kissing-the-rock-or-lessons-in-stabilizer-engineering","status":"publish","type":"post","link":"https:\/\/setsail.com\/kissing-the-rock-or-lessons-in-stabilizer-engineering\/","title":{"rendered":"Kissing the Rock, Or Lessons in Stabilizer Engineering"},"content":{"rendered":"<p><img loading=\"lazy\" decoding=\"async\" style=\"display: block; margin-left: auto; margin-right: auto;\" title=\"Kissing-the-Rock-238.jpg\" src=\"https:\/\/setsail.com\/wp-content\/uploads\/2010\/08\/Kissing-the-Rock-238.jpg\" border=\"0\" alt=\"Kissing-the-Rock-238.jpg\" width=\"576\" height=\"290\" \/><\/p>\n<p>It is the real world mistakes we have made which form much of the basis for how we do things. For example, the constant worry about 22 hull penetrations in our uninsured fiberglass 50 footer 32 years ago led to a compulsive drive to eliminate these in our own designs. It has been a dozen years since we have kissed anything hard below surface. No more. Today we did a really good job of it.<\/p>\n<p><!--more--><\/p>\n<p>Let us set the scene for you. We are coming into a pretty little bay, with a few cruising sailboats anchored, chatting with newly arrive daughter Sarah and friend Vera. It is overcast, so we do not have good underwater visibility.<\/p>\n<p>We note the two buoys, and all the yachts anchored to one side, and assume the buoys indicate an anchorage area, but do not check.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" style=\"display: block; margin-left: auto; margin-right: auto;\" title=\"Mallorca2--143.jpg\" src=\"https:\/\/setsail.com\/wp-content\/uploads\/2010\/08\/Mallorca2-143.jpg\" border=\"0\" alt=\"Mallorca2--143.jpg\" width=\"576\" height=\"438\" \/><\/p>\n<p>There is a slight question in the helmsman&#8217;s mind about this buoy, but rather than check the chart &#8211; we do have paper &#8211; or the RCC Piloting guide book &#8211; he continues slowly forward watching the depthfinder.<\/p>\n<p>And then kabang, and pieces \u00a0of stabilizer float to the surface.<\/p>\n<p>What we know now is this is a south cardinal buoy, but it does not look that way to us. Or, put another way, we did not recognize it as indicating a problem to its south side &#8211; which it does.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" style=\"display: block; margin-left: auto; margin-right: auto;\" title=\"Kissing-the-Rock-243.jpg\" src=\"https:\/\/setsail.com\/wp-content\/uploads\/2010\/08\/Kissing-the-Rock-243.jpg\" border=\"0\" alt=\"Kissing-the-Rock-243.jpg\" width=\"576\" height=\"396\" \/><\/p>\n<p>The guide book clearly calls out the rocks.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" style=\"display: block; margin-left: auto; margin-right: auto;\" title=\"Kissing-the-Rock-241.jpg\" src=\"https:\/\/setsail.com\/wp-content\/uploads\/2010\/08\/Kissing-the-Rock-241.jpg\" border=\"0\" alt=\"Kissing-the-Rock-241.jpg\" width=\"576\" height=\"378\" \/><\/p>\n<p>The poor quality Maptech electronic charts sort of indicate a problem, but we missed the danger signs and were instead watching the depthfinder.<\/p>\n<p>We back off the rock easily, anchor, and collect our now embarrassed wits.<\/p>\n<p>Mistakes made, all of which we no better than to commit:<\/p>\n<ul>\n<li>Failed to carefully read and reread the pilot book data.<\/li>\n<li>Not wearing polarized sunglasses which would have aided underwater viewing.<\/li>\n<li>Did not deploy and scan with sonar, normally standard for us if we are at all nervous.<\/li>\n<li>Took the fact that there were a bunch of anchored sailboats to indicate sufficient depth (they all draw more water than do we).<\/li>\n<li>Did not stop and assess things when the unusual tbuoys came into play.<\/li>\n<li>Finally, we were chatting and only paying partial attention coming into a new anchorage.<\/li>\n<\/ul>\n<p>Thats the bad news. Now the benefits. To begin with, we are fine structurally. No leaks (the keel leading edge took a real whack but aside from paint damage is fine). The stabilizer shaft appears OK as the fiberglass fin broke away from its stainless insert. If we can find a replacement fin in a timely manner it is a simple job to install once we are hauled out.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" style=\"display: block; margin-left: auto; margin-right: auto;\" title=\"Kissing-the-Rock-232.jpg\" src=\"https:\/\/setsail.com\/wp-content\/uploads\/2010\/08\/Kissing-the-Rock-232.jpg\" border=\"0\" alt=\"Kissing-the-Rock-232.jpg\" width=\"576\" height=\"384\" \/><\/p>\n<p>We are currently a single stabilizer vessel. We&#8217;ll adjust the control algorithms for this and begin testing motion. We assume our fin area is correct but now we will have a chance to see how things go with half the area. You ever know, we might be able to save some drag.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" style=\"display: block; margin-left: auto; margin-right: auto;\" title=\"Kissing-the-Rock-235.jpg\" src=\"https:\/\/setsail.com\/wp-content\/uploads\/2010\/08\/Kissing-the-Rock-235.jpg\" border=\"0\" alt=\"Kissing-the-Rock-235.jpg\" width=\"576\" height=\"465\" \/><\/p>\n<p>A word to our friends at NAIAD about the fin engineering and construction. This is a really poor way (in our \u00a0opinion) to build these foils. There is a core of unreenforced high density foam, or maybe it is resin and microspheres. Whatever, as you can see here it is brittle. The fiberglass laminate is the white line inside of the pink. It looks like a layer of matt and 24 ounce woven roving. The pink is fairing we added during sea trials to try and clean up what was a terribly distorted foil shape.<\/p>\n<p>Here is our suggestion. Assume these foils are going to hit things. Use a flexible foam, like Airex, which will absorb energy and localize damage. Match this with a resin system that has good flex characteristics, with a suitable reenforcement system. This way you could ding the foil on a rock, but not be faced with the hassle of hauling and replacing.<\/p>\n<p>One more benefit.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" style=\"display: block; margin-left: auto; margin-right: auto;\" title=\"Mallorca2--161.jpg\" src=\"https:\/\/setsail.com\/wp-content\/uploads\/2010\/08\/Mallorca2-161.jpg\" border=\"0\" alt=\"Mallorca2--161.jpg\" width=\"576\" height=\"266\" \/><\/p>\n<p>We&#8217;ve got some new Australian cruising friends.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" style=\"display: block; margin-left: auto; margin-right: auto;\" title=\"Mallorca2--158.jpg\" src=\"https:\/\/setsail.com\/wp-content\/uploads\/2010\/08\/Mallorca2-158.jpg\" border=\"0\" alt=\"Mallorca2--158.jpg\" width=\"576\" height=\"368\" \/><\/p>\n","protected":false},"excerpt":{"rendered":"<p>It is the real world mistakes we have made which form much of the basis for how we do things. <a class=\"read-more\" href=\"https:\/\/setsail.com\/kissing-the-rock-or-lessons-in-stabilizer-engineering\/\">&#8230;Read More<\/a><\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4],"tags":[],"class_list":["post-12819","post","type-post","status-publish","format-standard","hentry","category-dashew-blog"],"_links":{"self":[{"href":"https:\/\/setsail.com\/wp-json\/wp\/v2\/posts\/12819"}],"collection":[{"href":"https:\/\/setsail.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/setsail.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/setsail.com\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/setsail.com\/wp-json\/wp\/v2\/comments?post=12819"}],"version-history":[{"count":0,"href":"https:\/\/setsail.com\/wp-json\/wp\/v2\/posts\/12819\/revisions"}],"wp:attachment":[{"href":"https:\/\/setsail.com\/wp-json\/wp\/v2\/media?parent=12819"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/setsail.com\/wp-json\/wp\/v2\/categories?post=12819"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/setsail.com\/wp-json\/wp\/v2\/tags?post=12819"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}