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Seaworthiness
Greetings all, I'm considering building a kit Stornaway Weekender
www.scruffie.com as a teethcutting exercise; my primary objective is to get a handle on the bedrock principles of 'seaworthiness'. From random reading I've formed the impression that the Bristol Channel Pilot Cutter is the epitome of a seaworthy design. Colin Archer designs seem to get the big tick also. What I'm seeking is advice on the most 'seaworthy' yacht design available for a vessel under 35'. Becuase of the apparent advantages of heavy displacement & relative ease of fairing, I'm also considering a ferro hull ...any comments/observations on the pros/cons would be much appreciated. I've foundy the following salty site quite useful in terms of Aussie no-bull**** plain talking: http://members.optusnet.com.au/coast...rocruising.htm |
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#2
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Seaworthiness
Sorry to wander so far off topic, this post isn't much about boat
building. Peter Ward wrote: Greetings all, I'm considering building a kit Stornaway Weekender www.scruffie.com as a teethcutting exercise; Cute boats. Much lighter than their appearance would seem to indicate. my primary objective is to get a handle on the bedrock principles of 'seaworthiness'. The best 1 page primer on "seaworthiness" is an essay by Peter Duff (of Edey & Duff, the builders of the Stone Horse among other great boats). He sums it up thusly: 1- easy to handle 2- comfortable (which he explains differently and more sensibly than many people imagine 'comfort') 3- water tight integrity & reserve bouyancy 4- speed in sailing performance under a wide variety of conditions 5- beauty My own explanation, given the many many demonstrations of lengthy & perilous voyages in wildly unsuitable craft, is that seaworthiness consists of a great combination of skill and/or luck on the part of the skipper. This skill includes the ability to prepare & equip a boat rationally for a wide range of anticipated conditions. The luck includes not being there when very bad things happen, although careful attention to unobvious details in predicting such happenings is definitely a skill. From random reading I've formed the impression that the Bristol Channel Pilot Cutter is the epitome of a seaworthy design. Colin Archer designs seem to get the big tick also. While they are good boats for rough water sailing, and definitely can be said to maintain a more comfortable motion in a seaway (which, when things get *really* bad, ain't saying much), they are pre-1920s technology. While I agree with Peter Duff when he says, "The sea hasn't changed much" it is unwise to overlook the accomplishments of modern engineering & materials; also there are hazards nowadays such as being run down by a freighter or hitting a container, that the previous generation of old salts did not have to face. BTW one of the prime characteristics in a boats safety at sea is the ability to make distance to windward in deteriorating conditions... modern keels & rigs have a great advantage in this, which is one of the points I mentioned earlier to not overlook. Consider the design factors in the two boats named... both were intended for rough water sailing, intended to stay on station & be maneuverable in very bad conditions. They were not intended for long duration at sea, nor for carrying heavy loads; both were given hull & rig characteristics intended to the best for windward sailing ability given the technology of the era. Colin Archer worked on techniques of construction as much as hull & rig types, to get the strongest lightest hulls possible. Do these points tell you something about what the same service would indicate today? What I'm seeking is advice on the most 'seaworthy' yacht design available for a vessel under 35'. Becuase of the apparent advantages of heavy displacement & relative ease of fairing, I'm also considering a ferro hull ...any comments/observations on the pros/cons would be much appreciated. The problem with ferrocement is that it has no way of verifying hull integrity, and is prone to catastrophic rather than incremental failure. The main advantage of ferrocement is that it's cheap. For a vessel intended to take to sea, there are better ways to pinch pennies IMHO. I've foundy the following salty site quite useful in terms of Aussie no-bull**** plain talking: http://members.optusnet.com.au/coast...rocruising.htm Thanks for the link. Very interesting reading. Fresh Breezes- Doug King |
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#3
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Seaworthiness
I mostly agree with Doug, but would put emphasis elsewhere.
Seaworthiness is largely relative to where you want to go and when. A boat that would be perfectly fine in all conditions that you might meet on the East Coast of the USA (except a hurricane, for which you would have plenty of warning) would not be my first choice for doing a circumnav the wrong way in the Southern Ocean. But to build and equip for the latter when all you intend is the former is expensive and foolish. All boats are compromises, and all factors, including seaworthiness must be weighted intelligently. Speed is also a seaworthiness factor, as it gives you a better chance at getting out of the way of storms. Your Colin Archer will not be as fast as a modern design. Sayula II, a Swan 65, won the first Whitbread. She is much faster, size for size, than a Colin Archer design, yet strong enough to do a 180 in the Southern Ocean and come up with no significant damage. Doug also touches on the question of comfort. IMHO, comfort is a major seaworthiness factor. Unless you have a boat that will heave to and take care of itself, and the sea room to do it, someone has to be sailing the boat, which means that the crew has to be getting enough sleep and enough food to stay able to do what they need to do. As for ferro, I agree with Doug, but would add that a ferro boat is essentially unsalable (it may also be unsailable, as they tend to be heavy). While ferro can be cheap, why build in a material that no one wants to buy in order to save maybe 5 or 10% of the cost of the whole project? You can probably build in steel for very little more, and have a boat that you can sell. -- Jim Woodward www.mvFintry.com .. "DSK" wrote in message ... Sorry to wander so far off topic, this post isn't much about boat building. Peter Ward wrote: Greetings all, I'm considering building a kit Stornaway Weekender www.scruffie.com as a teethcutting exercise; Cute boats. Much lighter than their appearance would seem to indicate. my primary objective is to get a handle on the bedrock principles of 'seaworthiness'. The best 1 page primer on "seaworthiness" is an essay by Peter Duff (of Edey & Duff, the builders of the Stone Horse among other great boats). He sums it up thusly: 1- easy to handle 2- comfortable (which he explains differently and more sensibly than many people imagine 'comfort') 3- water tight integrity & reserve bouyancy 4- speed in sailing performance under a wide variety of conditions 5- beauty My own explanation, given the many many demonstrations of lengthy & perilous voyages in wildly unsuitable craft, is that seaworthiness consists of a great combination of skill and/or luck on the part of the skipper. This skill includes the ability to prepare & equip a boat rationally for a wide range of anticipated conditions. The luck includes not being there when very bad things happen, although careful attention to unobvious details in predicting such happenings is definitely a skill. From random reading I've formed the impression that the Bristol Channel Pilot Cutter is the epitome of a seaworthy design. Colin Archer designs seem to get the big tick also. While they are good boats for rough water sailing, and definitely can be said to maintain a more comfortable motion in a seaway (which, when things get *really* bad, ain't saying much), they are pre-1920s technology. While I agree with Peter Duff when he says, "The sea hasn't changed much" it is unwise to overlook the accomplishments of modern engineering & materials; also there are hazards nowadays such as being run down by a freighter or hitting a container, that the previous generation of old salts did not have to face. BTW one of the prime characteristics in a boats safety at sea is the ability to make distance to windward in deteriorating conditions... modern keels & rigs have a great advantage in this, which is one of the points I mentioned earlier to not overlook. Consider the design factors in the two boats named... both were intended for rough water sailing, intended to stay on station & be maneuverable in very bad conditions. They were not intended for long duration at sea, nor for carrying heavy loads; both were given hull & rig characteristics intended to the best for windward sailing ability given the technology of the era. Colin Archer worked on techniques of construction as much as hull & rig types, to get the strongest lightest hulls possible. Do these points tell you something about what the same service would indicate today? What I'm seeking is advice on the most 'seaworthy' yacht design available for a vessel under 35'. Becuase of the apparent advantages of heavy displacement & relative ease of fairing, I'm also considering a ferro hull ...any comments/observations on the pros/cons would be much appreciated. The problem with ferrocement is that it has no way of verifying hull integrity, and is prone to catastrophic rather than incremental failure. The main advantage of ferrocement is that it's cheap. For a vessel intended to take to sea, there are better ways to pinch pennies IMHO. I've foundy the following salty site quite useful in terms of Aussie no-bull**** plain talking: http://members.optusnet.com.au/coast...rocruising.htm Thanks for the link. Very interesting reading. Fresh Breezes- Doug King |
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#4
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Seaworthiness
Great post.
Thank you for pointing out those "forgotten factors" of seaworthiness: speed and comfort. -- Jacques http://www.bateau.com "Jim Woodward" jameslwoodward at attbi dot com wrote in message ... I mostly agree with Doug, but would put emphasis elsewhere. Seaworthiness is largely relative to where you want to go and when. A boat that would be perfectly fine in all conditions that you might meet on the East Coast of the USA (except a hurricane, for which you would have plenty of warning) would not be my first choice for doing a circumnav the wrong way in the Southern Ocean. But to build and equip for the latter when all you intend is the former is expensive and foolish. All boats are compromises, and all factors, including seaworthiness must be weighted intelligently. Speed is also a seaworthiness factor, as it gives you a better chance at getting out of the way of storms. Your Colin Archer will not be as fast as a modern design. Sayula II, a Swan 65, won the first Whitbread. She is much faster, size for size, than a Colin Archer design, yet strong enough to do a 180 in the Southern Ocean and come up with no significant damage. Doug also touches on the question of comfort. IMHO, comfort is a major seaworthiness factor. Unless you have a boat that will heave to and take care of itself, and the sea room to do it, someone has to be sailing the boat, which means that the crew has to be getting enough sleep and enough food to stay able to do what they need to do. As for ferro, I agree with Doug, but would add that a ferro boat is essentially unsalable (it may also be unsailable, as they tend to be heavy). While ferro can be cheap, why build in a material that no one wants to buy in order to save maybe 5 or 10% of the cost of the whole project? You can probably build in steel for very little more, and have a boat that you can sell. -- Jim Woodward www.mvFintry.com . "DSK" wrote in message ... Sorry to wander so far off topic, this post isn't much about boat building. Peter Ward wrote: Greetings all, I'm considering building a kit Stornaway Weekender www.scruffie.com as a teethcutting exercise; Cute boats. Much lighter than their appearance would seem to indicate. my primary objective is to get a handle on the bedrock principles of 'seaworthiness'. The best 1 page primer on "seaworthiness" is an essay by Peter Duff (of Edey & Duff, the builders of the Stone Horse among other great boats). He sums it up thusly: 1- easy to handle 2- comfortable (which he explains differently and more sensibly than many people imagine 'comfort') 3- water tight integrity & reserve bouyancy 4- speed in sailing performance under a wide variety of conditions 5- beauty My own explanation, given the many many demonstrations of lengthy & perilous voyages in wildly unsuitable craft, is that seaworthiness consists of a great combination of skill and/or luck on the part of the skipper. This skill includes the ability to prepare & equip a boat rationally for a wide range of anticipated conditions. The luck includes not being there when very bad things happen, although careful attention to unobvious details in predicting such happenings is definitely a skill. From random reading I've formed the impression that the Bristol Channel Pilot Cutter is the epitome of a seaworthy design. Colin Archer designs seem to get the big tick also. While they are good boats for rough water sailing, and definitely can be said to maintain a more comfortable motion in a seaway (which, when things get *really* bad, ain't saying much), they are pre-1920s technology. While I agree with Peter Duff when he says, "The sea hasn't changed much" it is unwise to overlook the accomplishments of modern engineering & materials; also there are hazards nowadays such as being run down by a freighter or hitting a container, that the previous generation of old salts did not have to face. BTW one of the prime characteristics in a boats safety at sea is the ability to make distance to windward in deteriorating conditions... modern keels & rigs have a great advantage in this, which is one of the points I mentioned earlier to not overlook. Consider the design factors in the two boats named... both were intended for rough water sailing, intended to stay on station & be maneuverable in very bad conditions. They were not intended for long duration at sea, nor for carrying heavy loads; both were given hull & rig characteristics intended to the best for windward sailing ability given the technology of the era. Colin Archer worked on techniques of construction as much as hull & rig types, to get the strongest lightest hulls possible. Do these points tell you something about what the same service would indicate today? What I'm seeking is advice on the most 'seaworthy' yacht design available for a vessel under 35'. Becuase of the apparent advantages of heavy displacement & relative ease of fairing, I'm also considering a ferro hull ...any comments/observations on the pros/cons would be much appreciated. The problem with ferrocement is that it has no way of verifying hull integrity, and is prone to catastrophic rather than incremental failure. The main advantage of ferrocement is that it's cheap. For a vessel intended to take to sea, there are better ways to pinch pennies IMHO. I've foundy the following salty site quite useful in terms of Aussie no-bull**** plain talking: http://members.optusnet.com.au/coast...rocruising.htm Thanks for the link. Very interesting reading. Fresh Breezes- Doug King |
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#5
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Seaworthiness
DSK wrote in message ...
& "Jim Woodward" jameslwoodward at attbi dot com wrote in message ... Thanks both for the excellent advice clearly based on extensive briny experience. I guess I was thinking of seaworthiness in the fairly narrow sense of being able to survive something like 'The Perfect Storm'; & particularly the ability to quickly self-right in the event of capsize. According to Czeslaw A. Marchaj in 'Seaworthiness : The Forgotten Factor' the "point of vanishing stability" et.al. of most modern yacht designs is woefully inadequate - deficiencies he attributes to the pervasive influence of International Offshore Rules & the 'floating gin-palace' ethos of the charter-boat industry, on modern yacht design & construction. This observation appears to have been borne-out empirically by the 1988 Sydney to Hobart Yacht Race http://www.radford-yacht.com/stablty1.html As a natural pessimist, I want to build the 'ultimate-unsinkable' craft, which will weather the worst that the sea can inflict; however, I get the distinct impression leafing through all the myriad yachting magazines, that most boats out there are little more than flimsy eye-candy. Just another prettified escapist consumer commodity designed more to part you from your hard-earned lucre, than to be truly "worthy of the sea". Yet on the other hand I continually read accounts of wildly improbable craft -http://www.famoussmallboats.com/ - criss-crossing the Atlantic & Pacific with apparent ease. All quite confusing really. |
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#6
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Seaworthiness
The Perfect Storm was in the North Atlantic in October -- in winter, in
weather terms. It's no accident that "Winter North Atlantic" has its own loadline, and that it's the one that requires the most freeboard of all. And, although both the book and the movie have obscured reality somewhat (the movie much more than the book), it appears the Andrea Gail had a number of seaworthiness problems. If you choose your times and places with some intelligence -- stay out of hurricane areas, the Winter North Atlantic, the Southern Ocean, then you're very unlikely to face survival weather. Many circumnavigators will tell you that they never saw serious weather on their entire trip -- our highest wind speed was around 42 knots. I, too, am a natural pessimist. People who go to sea should understand that Mother Nature does not suffer fools lightly. But pessimism should not bring paranoia. As I said earlier in this thread, designing and equipping a boat for the worst possible weather is expensive and unnecessary unless you really intend to go out at times and places where such weather is really an issue. Your "ultimate-unsinkable craft, which will weather the worst that the sea can inflict" is a wonderful thing to think about, but I wouldn't want to sail it, as it would likely be slow, uncomfortable, and difficult for its crew. I'd rather choose my times and places and stay away from anything anywhere near "the worst the sea can inflict". I'm pretty sure that's a realistic goal for all except masochists and thrill seekers. As for the quality of production boats, there are production boats that I wouldn't want to take out of sight of land and others that I would happy with almost anywhere, although not at all times of year. You pay your money and, by and large, you get what you've paid for. And, BTW, they're not hard to tell apart at the boat shows -- if you see two boats about the same size and weight and one has fittings -- turnbuckles, for example -- noticeably heavier than the other, you can guess which one I'd rather be aboard. -- Jim Woodward www.mvFintry.com .. "Peter Ward" wrote in message m... DSK wrote in message ... & "Jim Woodward" jameslwoodward at attbi dot com wrote in message ... Thanks both for the excellent advice clearly based on extensive briny experience. I guess I was thinking of seaworthiness in the fairly narrow sense of being able to survive something like 'The Perfect Storm'; & particularly the ability to quickly self-right in the event of capsize. According to Czeslaw A. Marchaj in 'Seaworthiness : The Forgotten Factor' the "point of vanishing stability" et.al. of most modern yacht designs is woefully inadequate - deficiencies he attributes to the pervasive influence of International Offshore Rules & the 'floating gin-palace' ethos of the charter-boat industry, on modern yacht design & construction. This observation appears to have been borne-out empirically by the 1988 Sydney to Hobart Yacht Race http://www.radford-yacht.com/stablty1.html As a natural pessimist, I want to build the 'ultimate-unsinkable' craft, which will weather the worst that the sea can inflict; however, I get the distinct impression leafing through all the myriad yachting magazines, that most boats out there are little more than flimsy eye-candy. Just another prettified escapist consumer commodity designed more to part you from your hard-earned lucre, than to be truly "worthy of the sea". Yet on the other hand I continually read accounts of wildly improbable craft -http://www.famoussmallboats.com/ - criss-crossing the Atlantic & Pacific with apparent ease. All quite confusing really. |
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#7
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Seaworthiness
"Peter Ward" wrote in message m... I guess I was thinking of seaworthiness in the fairly narrow sense of being able to survive something like 'The Perfect Storm'; & particularly the ability to quickly self-right in the event of capsize. According to Czeslaw A. Marchaj in 'Seaworthiness : The Forgotten Factor' the "point of vanishing stability" et.al. of most modern yacht designs is woefully inadequate - deficiencies he attributes to the pervasive influence of International Offshore Rules & the 'floating gin-palace' ethos of the charter-boat industry, on modern yacht design & construction. This observation appears to have been borne-out empirically by the 1988 Sydney to Hobart Yacht Race http://www.radford-yacht.com/stablty1.html In the Sydney-Hobart, the main lesson is don't get caught where the conditions are bad. The analysis showed that it didn't really matter what type of boat you were in - heavy narrow boats, light beamy ones, and everything in between got capsized.. But the boats in a certain area, the area with the worst conditions, were most likely to capsize. John Rousmaniere in his excellent book Fastnet Force Ten came to a somewhat similar conclusion about the Fastnet - that boats in a certain area were more likely to be capsized. That doesn't validate poor design, but it tells me that if you are in the wrong place at the wrong time, it doesn't matter what kind of boat you're in. Personally, Id recommend a boat with a limit of positive stability of greater than 120 degrees, with all the cruising gear included in the calculation (which is probably not the design condition). And make sure your boat is ISAF Category 1 or zero compliant. Design is one element of seaworthiness, but the crew (and luck) is equally or more important. Consider that the boat that won the 98 Sydney-Hobart was a light 35 footer that consistently does well in that race and you'll start to get a feeling that those guys could probably sail a crappy old raft through just about anything. And it sounds like you've read the books about the guys with no experience who cross oceans, so you can see the part that lady luck plays as well. More books that would probably be of interest to you: Heavy Weather Sailing has lots of good info, including chapters about desingn features. The Drag Device Data Book if you're really serious about going offshore. Fastnet Force 10. There's also a book about the Queen's Birthday Storm that hit a bunch of cruisers in the South Pacific, but I can't remember the name right now. As a natural pessimist, I want to build the 'ultimate-unsinkable' craft, which will weather the worst that the sea can inflict; however, I get the distinct impression leafing through all the myriad yachting magazines, that most boats out there are little more than flimsy eye-candy. Just another prettified escapist consumer commodity designed more to part you from your hard-earned lucre, than to be truly "worthy of the sea". Well, there are good boats and bad boats. There are quite a few seaworthy ones available for good prices. Some of them are lightweight flyers, and some are heavy tanks. It's hard to make a boat unsinkable but it is possible to minimize the probability. Watertight subdivision is one way to do it, but you will find that only the Amel boats come from the factory that way. Ramblin' Matt |
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#8
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Seaworthiness
"Peter Ward" wrote in message m... I guess I was thinking of seaworthiness in the fairly narrow sense of being able to survive something like 'The Perfect Storm'; If it's The Perfect Storm you want to survive then clearly you need a Westsail 32. A W32 DID survive the Perfect Storm. Unmanned no-less and, as far as I last heard is still sailing. Yet another Steve |
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#10
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Seaworthiness
define "seaworthiness"
I thought it meant a boat that would take care of itself in rough conditions, not a boat that could perhaps outrace the weather. This outracing the weather is only helpfull along the coast where, given advance warning of deteriorating weather conditions over the radio, the faster boat can run for cover. Its not much help mid ocean in a big weather system. The main indicator of seaworthiness is the displacement to length ratio. Boats with a ratio over (I think) 300 are the most seaworthy. These are ocean going cruisers. Because boats are sold by the pound they are expensive. I know lighter materials can cost more per pound by they don't have as many pounds. The heavy cruisers also have more room for accomdation and storage and a better comfort factor. They can make good time under all conditions but light winds. There are books on cruising sailboats as distinct from racing and coastal sailboats. One that I read recently is Danny Greene's "Cruising Sailboat Kinetics" (1984). -- ------------------------------------------------------------------------------ William R Watt National Capital FreeNet Ottawa's free community network homepage: www.ncf.ca/~ag384/top.htm warning: non-freenet email must have "notspam" in subject or it's returned |
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