The case of the missing chainplateThe importance of chain plates cannot be over emphasized, because when they fail, disaster is eminent. Many sail boats have accessible chain plates which are easy to inspect. Some, especially older models, 60,s and 70,s vintage, have port and starboard chain plates which are secured to plywood which is laminated and then secured to the structure. Many companies used plywood which is sandwiched between layers of woven roving and secured to the hull with woven roving. This technology would be great if, over time, water did not leak through the deck penetration and saturate the plywood. Once the plywood is wet, rot begins to set in, and it does not take long before the chain plate supporting plywood is rotted away completely. In order to check these types of secured chain plate supports they must be sounded and in some cases core sampled. Also, the securing bolts may be loose if the wood has rotted away. Another situation that is rare but serious, I will call the “Case of The Missing Chain Plate”. All boat owners are not created equal, as interior decorating to some owners may be more important to those darn things that stick out over there, (chain plate supports). I received a call one day from a judge who was having trouble collecting a settlement from his insurance company after a dis-masting during his first race. I arrived at the vessel with the judge and was informed that the judge had been working on the vessel for the past year and had made serious modifications to the interior so that it was very comfortable, and just a great live aboard and summer home. The judge explained how the dis-masting occurred during his first race while he was on a broad reach with winds about 25 knots. He then explained how his crew brought to his attention that the deck, amidships, right along the starboard side was beginning to lift, a couple of inches at first and then a foot during the next minute or so. As luck would have it he said “a slight gust came along” and off went the mast to port. The mast was keel stepped and broke off clean at the deck and departed to the water with all attached gear and sails. Luckily no one was injured and the vessel was towed back to port. The good judge’s racing career was temporarily put on hold. How was this possible on such a large, well designed, contemporary sloop? The good judge hired a crew to remodel the main salon in order to make it more spacious. The crew, he thought, was great as they had done a wonderful job on his new kitchen at home. As you might expect the crew had no knowledge of vessel maintenance or structures and simply removed anything they could to make the main salon more spacious. They removed the chain plates, modified them and re-secured them to the underside of the deck. A new head liner was installed and everything looked great to the judge when the crew departed. The bottom line is the insurance company declined to pay the claim because of the modifications which were made to the chain plate supports caused the vessel to be unsafe. As removing chain plate supports because there were in the way is not acceptable. In my sailing experience, I have observed more than a few dis-masted older Pearson’s and Bristols towing their standing rigging back to port and those were the lucky ones. A dis-masting under the right conditions can be fatal to the vessel and its crew. Typically the bow and stern plates are visible as they are usually bolted right to the hull in plain sight and any defect should be obvious. Over the years I have observed vessel owners tuning their rigging in preparation for a race. In one case the owner said to me, “this stay was tight a few minutes ago, I tightened it just a little more to be safe, and now it’s loose”. A few minutes later he and his crew sailed off for the Wednesday night club race. This owner had tightened the rigging to the point of collapse, and he actually separated the plywood mounted chain plate from the hull. I could not believe he was sailing away. Fortunately there was very little wind for the race that night and he made it back to the dock still unaware of what might have happened.