I just picked up an old coronado 30' for a parts boat. There is some kind of trim tab on the trailing edge of the fin keel. It is moved by a lever in the cockpit from port to starboard depending on which tack you are on. I will probably never sail this boat so i have 2 questions. First, i am assuming that the fin gives you extra "lift" to windward? How much does it actually help? Second, does anybody know of a coronado owners group so i can see if anybody wants anh of the mechanism? I can imagine it would be hard for someone restoring one to find these parts and i wouldnt want to scrap them. Thanks -John
Back in the late 60's, early 70's, there was a lot of work done on trim tabs. They fell into disfavour because they added a lot more complexity and uncertainty than benefits. If you were "America's Cup" expert they could give a slight advantage but otherwise they were simply more trouble than they were worth. The IOR essentially outlawed them.