On 28 Jul 2001 10:08:46 -0700 "Michael Maurice" <mikem@yachtsdelivered.com> writes: > > One of my pet peeves has to do with the ever increasing level of > junk being > placed above the center of gravity on most boats. I have to agree with Mike that this is a problem on many boats today. But this is a generalized statement that needs some further explanation and clarification. Some additional weight aloft is not necessarily a problem for all boats. In fact Jim Leischman writes in the 3rd edition of Voyaging Under Power. p. 128, "We now encourage our owners to carry a sizable dinghy and deck boxes on the boat deck." He was speaking about his N46 design. He feels that it will increase the comfort of the ride without sacrificing security. It is also our opinion that carrying some additional weight on the boat deck of our designs is not necessarily a bad idea. In fact we design a paravane stabilizer system that stows the "fish" at the ends of the outrigger poles in a vertical position. This is the way that many full displacement, ballasted fishing boats do it here on the West Coast with no adverse effects. But anything an owner does should be done with common sense. There are limits to how much should be stowed above the CG. Generally speaking full displacement hulls that are ballasted (some full displacement boats are not ballasted) will react more favorably to additional weight on the boat above the CG. Semi displacement, unballasted hulls tend to be more sensitive to weight distribution. We favor a full displacement hull with about 20% to 25% of the displacement in ballast encapsulated deep in the keel. Yes, this type of hull does exhibit a slow period of roll but most people describe it as being comfortable in a seaway. On Sat, 28 Jul 2001 10:25:36 -0700 "Hal Wyman" <twl@halwyman.com> writes: > I think he neglected to mention the positive effect increasing the > roll > moment of intertia (by placing weight far from the center of roll) > can have > on stability in some cases. >it is > certainly a > matter for a qualified marine architect to consider. > Adding weight or deleting weight from the topsides can upset the delicate balance of any design. Hal is correct and gives some good advice, any changes should be carefully considered by consulting with a qualified naval architect or marine engineer. In fact any ideas presented on the Trawler World List (including mine) should be discussed with a qualified professional before implementation. Patrick Gerety Willard Marine www.willardmarine.com mailto: trawlers@willardmarine.com