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Hi and welcome! I am a sailing and mountain enthusiast. I live on Cape Cod and in Vermont so I have the best of both worlds! I am a musician and computer programmer. I designed, produce and market a CDROM called Learn to Sail! with Multimedia! A digital textbook that delivers information in an entertaining, interactive way. Learn to Sail is a great accompaniment to sailing lessons. A digital textbook that delivers information in an entertaining, interactive way. Digital video is from Sail Magazine, and material is presented by voice, which is played concurrently with displayed text. And there are quizzes along the way to test your knowledge.

Friday, May 02, 2008

Multihulls- Part 1



Welcome aboard to my Sailing Tips Blog! Here we have MULTIHULLS- Catamarans and Trimarans. Please feel free to comment on anything here and visit our Web Site for a free Rules of the Road download!

History -The catamaran is one of the oldest types of craft known. The word Catamaran has its origin in Malayan language -- Catu (to tie) and Maran ( log). Early Polynesians would lash two large canoes together and sail a whole village's worth people from one village to another, which usually meant sailing from one island to another. These people considered the stability of a two hulled vessel to be safer than that of just one hull. Until two centuries ago Polynesia was totally isolated from the rest of the civilized world, which was developing boats along what we now think of as more traditional lines - single-hulled keel boats, or monohulls.
In the 1780s Captain Cook reported seeing beautiful boats of up to 120 feet long which were built of painstakingly painted and polished wood. Exposure to the outside world brought European diseases to these people, who had no immunities to them. The populations and societies were ravaged and these beautiful vessels rotted away. Outside of some native activity in the Hawaiian islands the catamaran design disappeared.
Then, in the late 1870s, Nathaniel Herreshoff designed and built the 25 foot catamaran Amaryllis. In 1876 he entered it in the New York Yacht Club's Centennial Regatta and easily beat every other boat in the fleet. That this upstart radical "new" design should win so handily was deemed unacceptable, and catamarans were barred from racing. This decision stopped the further development of multihulls cold. Mr. Herreshoff and his son, L. Francis, continued to design and build them for themselves, adding centerboards to each hull for better maneuverability, but their designs never gained acceptance.

1952 -- in England, the Prout brothers designed a U shaped hull, instead of the V shape that had preceded it, and they included centerboards. Now the boats would actually tack. They became popular in Europe because of their speed and comfort, and the long slow process of design evolution took a step forward. By the late 50's there were quite a few sailors experimenting with new designs and building materials. With the advent of fiberglass, resins, and marine plywood these boats could be built light and strong. In the 1960's Rudy Choy of Hawaii was designing and building race winning, ocean capable catamarans which are still viable today.
During the 1960's and 1970's an American designer named Arthur Piver was singularly responsable for the building of hundreds of trimarans in the backyards of would-be sailors. Unfortunately, some of his claims were not realistic- he maintained that anyone without carpentry or sailing experience could quickly and cheaply build one of his "non-capsizable" designs and sail around the world. There were so many of his boats under construction at one time that there was no way he could even attempt to ensure that the builders were using proper construction techniques, or even sticking to his plans. This resulted in builders making major and often unsafe modifications to his designs, and in many boats being built poorly and with inferior materials. There are still many old Pivers out sailing that are safe and comfortable, but there are countless others that rotted away, capsized, or broke up at sea due to shoddy construction. Piver himself disappeared at sea on a boat of his own design, albeit one that he did not build himself. All of this did nothing to help the reputation of multihulls, a legacy that unfortunately exists in the minds of many today.

Jim Brown, a protege of Piver, started designing his own trimarans, called Searunners. He designed them with a wider beam for a safer, more stable platform, along with other modifications. Soon Norm Cross, Lock Crowther, John Marples, and countless designers from all over the world were building on the lessons that could be learned from previous designs, both with trimarans and catamarans. These designers realized the need for detailed, precise plans, and for the designer to be involved with the builder from day one of construction in order to help to create a safe, fast, comfortable vessel.

The racing world is where multihulls have had a real chance to show the world their performance potential . In the 1976 OSTAR Mike Birch came in second place on the Third Turtle, Dick Newick's VAL design 31 foot trimaran. The first place winner that year was Eric Taberly on his 71 foot monohull. This was the last year in which a monohull won this race. Dick Newick's designs also captured the attention of Phil Weld, who won the 1980 OSTAR in the Newick trimaran, Moxie.

The high profile of racing, the money that racing has brought into their development and improvement, as well as the evolution of new, lightweight synthetic building materials have all contributed to the high quality of multihull craft that is being built today. They have gained worldwide acceptance.


What are the advantages and disadvantages of multihulls?

Advantages.

Stability -- It's almost impossible to sink a properly built multihull, short of blowing it up or burning it down. A common misconception is that trimarans and catamarans are easily capsized. This is not true of cruising multis -- they are stiff and stable and usually need a very rare and extraordinary set of circumstances before they'll go over. It is true that once they go over they stay over, but they will not sink, even when inverted. The crew of a capsized multi still has the mother ship and the supplies aboard to sustain life for however long it takes for a rescue. This is in contrast to a monohull, which if holed or capsized with hatches open will very quickly sink, leaving its inhabitants swimming or in a life raft. The likelihood that a modern cruising multihulls will capsize is about the same as the likelihood that a monohull will sink.

Speed - Almost without exception, a modern multi will be substantially faster than a monohull of comparable length. Speed is not only fun, it's an under appreciated safety feature. On a sailing passage, the longer a boat is exposed to the sea and the vagaries of weather, the better are the chances that it will meet with dangerous conditions. A North Atlantic crossing that takes under 10 days is likely to be safer than one that takes 3 weeks. A lot of weather can happen in three weeks, or a crew member can become dangerously sick and need medical attention fast. It's good to be able to step on the gas and get there.

Jibing -- These boats are so beamy that in a downwind situation the preventer can be secured far outboard, giving the main a lead that results in a nice wide, flat sail area and absolute control over the boom. Since multihulls move at such high speeds downwind, there is less wind pressure actually behind the sail, making it easy to control it during the entire manuever. The boat continues to sail flat and steering is easy. Jibing a multihull is a very smooth operation, and puts much less stress and strain on both equipment and crew than it does with a monohull in the same situation. In a jibe a keel boat will tend to roll and try to round up into the wind as the mainsail fills on the new tack, making steering tricky.

Comfort - It's nice to be comfortable. After spending time on a modern multihull few people would argue that they are not considerably more comfortable than a keel boat. With their wide stable platforms catamarans don't heel at all, trimarans very little, and most people find their motion to be easier than that of single hulled boats. Comfort is also another very important safety feature. On a stable, smoothly moving boat it's easier to prepare and eat regular meals, and crew members can sleep without having to tie themselves in. A well rested, well fed crew is a much clearer minded, safer and happier one than a seasick, exhausted, poorly fed one.

Deck Space -- on a boat where 24 feet of beam is common, there's plenty of room to walk around. Dingy storage is not a problem.

Shallow Draft --Most multihulls have a very shallow draft -- 2-4 feet. What a luxury to be able to manuever through a crowded anchorage and move up front into only 3 or 4 feet of water and drop anchor. In water this shallow it's easy to see how well set your anchors are, or to hand set them if necessary. So what if all those big heavy boats behind you drag anchor? You're upwind from them all, and are safe from being crashed into by drifting, dragging boats. Many beautiful, private anchorages are out of reach of deep draft boats, but are perfect for shallow draft vessels.
Run aground? No problem. The boat will sit level and undamaged. Just wait for a rising tide, if you can, or perhaps you can jump in and push the boat off. ( Be careful if you do this -- wear shoes, and be sure that you can get back on board). You may also be able to walk out to deeper water and hand set an anchor that can then be used to kedge the boat off.


Conme back soon and we will explore the disadvantages!
Come visit our Web Site, sign up for our Free Monthly Sailing Tips newsletter, and check out our Interactive Sailing training CDROM. I and my crew wish you the best in your sailing endeavors! Best to you, Sailor Cull _/)_

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