Is the Hunter Legend 35.5 a strong enough boat to cross the Atlantic ocean? Has it been done yet? Thanks, Laval
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Archives for Blue Water or Offshore
Check the archives - this is a much discussed topic. There are a lot of preparations for offshore work that most production yachts need. The capsize ratio of 1.99 indicates more research into the ability of the boat to protect the crew if (in the worst case) it were rolled by a large breaking wave. I'd try to get the "angle of vanishing stability" from Hunter. You are looking for a number over 140 degrees there according to "Adlard Coles Heavy Weather Sailing." The point is that at sea, you cannot get to a harbor if an unexpected severe storm develops. David Lady Lillie
Check the archives - this is a much discussed topic. There are a lot of preparations for offshore work that most production yachts need. The capsize ratio of 1.99 indicates more research into the ability of the boat to protect the crew if (in the worst case) it were rolled by a large breaking wave. I'd try to get the "angle of vanishing stability" from Hunter. You are looking for a number over 140 degrees there according to "Adlard Coles Heavy Weather Sailing." The point is that at sea, you cannot get to a harbor if an unexpected severe storm develops. David Lady Lillie
Seattle to Panama then to Florida
Some friends of ours, Len & Jane Thornbeck, went from Seattle to the Panama Canal and then up to Florida via the Gulf of Mexico. They were well up in their 60s and did perfectly fine. Experienced some really tall waves near Coos Bay (the setting sun cast a shadow at the top spreader when they were in the trough) and really high winds near Nicaragua. The uphill bash up the Gulf of Mexico got water in their V-berth (see my anchor pan seal comments everywhere). What was that BIG hurricane that hit Florida around '93, '94 or '95? Came within a few miles of them on the 'east coast' but didn't cause any damage to the boat - tied to a couple pilings. The Seattle to Florida passage included some really long legs and rough conditions so it would definitely be classified as "blue water". Having said that, Len and Jane were not your average sailors, either. Another 35.5 won it's division in the Pacific Cup (San Francisco to Hawaii) in the double-handed class and I'd think this would classify as a blue-water trip too. I wouldn't put the 35.5 in the same category as a Westsail 32 where you might batten the hatches and go to sleep when the hurricane hits. Good planning means you wouldn't be there. It's a coastal cruiser and should be used accordingly but people have crossed the Atlantic on surfboards. Look at the archives and there are links to small craft that have made the trip. I think the sailor has a heck of a lot to do with it, both with gear, planing, and abilities.
Some friends of ours, Len & Jane Thornbeck, went from Seattle to the Panama Canal and then up to Florida via the Gulf of Mexico. They were well up in their 60s and did perfectly fine. Experienced some really tall waves near Coos Bay (the setting sun cast a shadow at the top spreader when they were in the trough) and really high winds near Nicaragua. The uphill bash up the Gulf of Mexico got water in their V-berth (see my anchor pan seal comments everywhere). What was that BIG hurricane that hit Florida around '93, '94 or '95? Came within a few miles of them on the 'east coast' but didn't cause any damage to the boat - tied to a couple pilings. The Seattle to Florida passage included some really long legs and rough conditions so it would definitely be classified as "blue water". Having said that, Len and Jane were not your average sailors, either. Another 35.5 won it's division in the Pacific Cup (San Francisco to Hawaii) in the double-handed class and I'd think this would classify as a blue-water trip too. I wouldn't put the 35.5 in the same category as a Westsail 32 where you might batten the hatches and go to sleep when the hurricane hits. Good planning means you wouldn't be there. It's a coastal cruiser and should be used accordingly but people have crossed the Atlantic on surfboards. Look at the archives and there are links to small craft that have made the trip. I think the sailor has a heck of a lot to do with it, both with gear, planing, and abilities.
Transat
In May this year I sailed my Hunter 34 across the Atlanic from Tampa to Italy. I chose the quicker but rougher route from Bermuda to Azores reaching 40 degrees north.The boat rode the heavy weather well and I would definately say they are safe for ocean crossing aslong as the right equipment is carried. Florida - Bermuda took 9 days Bermuda - Azores took 17 days Azores - Portugal took 9 days Portugal - Italy took 2 months (lovely cruising)
In May this year I sailed my Hunter 34 across the Atlanic from Tampa to Italy. I chose the quicker but rougher route from Bermuda to Azores reaching 40 degrees north.The boat rode the heavy weather well and I would definately say they are safe for ocean crossing aslong as the right equipment is carried. Florida - Bermuda took 9 days Bermuda - Azores took 17 days Azores - Portugal took 9 days Portugal - Italy took 2 months (lovely cruising)
Agree with David; except for "capsize ratio"....
What David calls "capsize ratio" is actually the CSF (Capsize Screening Factor) which after the Fastnet Storm a few decades ago was coined as a possible discriminant function between vessels that were rolled in that storm and vessels that were not. Actually, simple vessel length predicts that tendency just about as well, as can be seen from the final table in John Rousmaniere's book "Fastnet Force 10". Whether the CSF (a purely empirical number based on far too small a population to make statisticical sense in view of the many degrees of freedom in these complex phenomena) ever had any value or not, it is now being discredited by leading naval architects, e.g. because of the major changes in yacht design and construction since the Fastnet race. Even static "angle of vanishing stability" number calculations don't make much sense in a practical cruising vessel where rarely everything is bolted down far enough to keep the Center of Gravity in place (not to mention many, many hundreds or even thousands of pounds in human body as well as water and fuel weights that get shifted around in a major capsize or near-capsize event). Nonetheless, anyone still feeling strongly about the CSF can just buy a big old 1000 pound fisherman's anchor (and even hoist that into the top of the mast) if that makes one feel more secure...... Have fun! Flying Dutchman "Rivendel II"
What David calls "capsize ratio" is actually the CSF (Capsize Screening Factor) which after the Fastnet Storm a few decades ago was coined as a possible discriminant function between vessels that were rolled in that storm and vessels that were not. Actually, simple vessel length predicts that tendency just about as well, as can be seen from the final table in John Rousmaniere's book "Fastnet Force 10". Whether the CSF (a purely empirical number based on far too small a population to make statisticical sense in view of the many degrees of freedom in these complex phenomena) ever had any value or not, it is now being discredited by leading naval architects, e.g. because of the major changes in yacht design and construction since the Fastnet race. Even static "angle of vanishing stability" number calculations don't make much sense in a practical cruising vessel where rarely everything is bolted down far enough to keep the Center of Gravity in place (not to mention many, many hundreds or even thousands of pounds in human body as well as water and fuel weights that get shifted around in a major capsize or near-capsize event). Nonetheless, anyone still feeling strongly about the CSF can just buy a big old 1000 pound fisherman's anchor (and even hoist that into the top of the mast) if that makes one feel more secure...... Have fun! Flying Dutchman "Rivendel II"
So, Henk, you agree
with John and me that the Legend 35.5 is a very capable coastal cruiser? I read the various designer columns in several magazines, and enjoy books on the subject. I have never heard the capsize screen "discredited" by a naval architect. Instead, they refer to it as an approximate indicator. It has nothing to do with the probability of being rolled by waves in an extreme storm, however. It does address the design's ability to quickly recover from being rolled without loss of crew. It is a stand-in for the "Angle of Vanishing Stability" since many yacht manufacturers don't publish stability curves for their yachts. I would observe that the capsize screen does a good job of capturing the designers intent in designing a boat for roomy speed versus off-shore safety. You are right about the importance of length in determining whether a yacht will be rolled. The tank tests, and actual data show that a breaking wave with height 35% to 55% of the yacht's length will roll it if it comes abeam. But the design does make up the difference from 35% to 55%. Angle of Vanishing Stability(AVS), and the stability curve itself, together with the boats design features are the best indicators of response to being rolled, precisely because they predict dynamic, not static behavior. A boat with an AVS over 140 degrees is basically unstable when inverted and will rapidly recover, avoiding crew loss in the cockpit. A boat with an AVS under 120 degrees could easily stay inverted, as has occurred in numerous cases in Fastnet, Hobart, and other races. You are right that loading of a boat will change its AVS. But the effects are very predictable: stowing below the settees or beds, or in the bilge increases AVS; all other loading actions or modifications decrease it. Most modern production boats are being designed with long beam carried well aft, high freeboard, low weight, minimal overhangs (length overall compared to the waterline), and in-mast furling options. This means great accommodations below, low cost, and high initial stability which allows them to carry lots of sail in low winds. The long waterline is another advantage for speed. But these same characteristics all reduce the AVS and make the boat more likely to stay inverted longer if rolled. So they are designated coastal cruisers, because the crew should be able to find a safe port if an extreme storm is reported, or if it arises too quickly to find some safe shelter before the crew is totally worn out. The Legend 35.5 is designed for the cruise from California to the East Coast via the canal, and Caribbean. And we loved the Hunter 340 for our cruise of the North Channel last summer. But I'd much rather have a Cherubini designed Hunter 33 for blue water. (To use examples described on this site.) My point, and that made very convincingly by Adlards Heavy Weather is that we should understand these risks before planning a cruise that will expose us to them. David Lady Lillie
with John and me that the Legend 35.5 is a very capable coastal cruiser? I read the various designer columns in several magazines, and enjoy books on the subject. I have never heard the capsize screen "discredited" by a naval architect. Instead, they refer to it as an approximate indicator. It has nothing to do with the probability of being rolled by waves in an extreme storm, however. It does address the design's ability to quickly recover from being rolled without loss of crew. It is a stand-in for the "Angle of Vanishing Stability" since many yacht manufacturers don't publish stability curves for their yachts. I would observe that the capsize screen does a good job of capturing the designers intent in designing a boat for roomy speed versus off-shore safety. You are right about the importance of length in determining whether a yacht will be rolled. The tank tests, and actual data show that a breaking wave with height 35% to 55% of the yacht's length will roll it if it comes abeam. But the design does make up the difference from 35% to 55%. Angle of Vanishing Stability(AVS), and the stability curve itself, together with the boats design features are the best indicators of response to being rolled, precisely because they predict dynamic, not static behavior. A boat with an AVS over 140 degrees is basically unstable when inverted and will rapidly recover, avoiding crew loss in the cockpit. A boat with an AVS under 120 degrees could easily stay inverted, as has occurred in numerous cases in Fastnet, Hobart, and other races. You are right that loading of a boat will change its AVS. But the effects are very predictable: stowing below the settees or beds, or in the bilge increases AVS; all other loading actions or modifications decrease it. Most modern production boats are being designed with long beam carried well aft, high freeboard, low weight, minimal overhangs (length overall compared to the waterline), and in-mast furling options. This means great accommodations below, low cost, and high initial stability which allows them to carry lots of sail in low winds. The long waterline is another advantage for speed. But these same characteristics all reduce the AVS and make the boat more likely to stay inverted longer if rolled. So they are designated coastal cruisers, because the crew should be able to find a safe port if an extreme storm is reported, or if it arises too quickly to find some safe shelter before the crew is totally worn out. The Legend 35.5 is designed for the cruise from California to the East Coast via the canal, and Caribbean. And we loved the Hunter 340 for our cruise of the North Channel last summer. But I'd much rather have a Cherubini designed Hunter 33 for blue water. (To use examples described on this site.) My point, and that made very convincingly by Adlards Heavy Weather is that we should understand these risks before planning a cruise that will expose us to them. David Lady Lillie
CSF vs AVS
As David points out, the angle of vanishing stability (AVS) is the heart of the matter for predicting the reaction of a yacht capsized, a large angle assuring that an inverted geometry is transitory (like balancing an egg on its end) as long as the envelope of the hull stays intact, . Henk's comment questioning even the AVS because of the supposed certainty of things moving around in a capsize is disingenuous. It goes without saying that a prudent offshore sailor (like Henk) will do everything possible in stowing and securing to keep things, (especially heavy things) in place and low whatever the boat motion. Evidently, the reason for the development of capsize screen factor (CSF) in the first place was the lack of easy availability of the fundamental stability calculations that the AVS represents. Thus the developement of the CSF which is just an index, calculated from readily available boat parameters. Boats in this index formula deriving sample would probably not have carried weight at the mast top so Henk's use of this example for the purpose of discrediting the CSF instead just shows the limitations of any index formula. As Don Casey points out in the referenced article below, the best way to get rid of the CSF is for the boat designers to provide the fundamental buoyancy calculations which would include David's AVS. In the meantime, the CSF does serve as Casey points out to focus on beam as something other than an unalloyed positive.
As David points out, the angle of vanishing stability (AVS) is the heart of the matter for predicting the reaction of a yacht capsized, a large angle assuring that an inverted geometry is transitory (like balancing an egg on its end) as long as the envelope of the hull stays intact, . Henk's comment questioning even the AVS because of the supposed certainty of things moving around in a capsize is disingenuous. It goes without saying that a prudent offshore sailor (like Henk) will do everything possible in stowing and securing to keep things, (especially heavy things) in place and low whatever the boat motion. Evidently, the reason for the development of capsize screen factor (CSF) in the first place was the lack of easy availability of the fundamental stability calculations that the AVS represents. Thus the developement of the CSF which is just an index, calculated from readily available boat parameters. Boats in this index formula deriving sample would probably not have carried weight at the mast top so Henk's use of this example for the purpose of discrediting the CSF instead just shows the limitations of any index formula. As Don Casey points out in the referenced article below, the best way to get rid of the CSF is for the boat designers to provide the fundamental buoyancy calculations which would include David's AVS. In the meantime, the CSF does serve as Casey points out to focus on beam as something other than an unalloyed positive.
Plenty of food for a good discussion!
In fact, because of limited time right now, let me just try to give Terry some more food for thought: No question that the AVS is a little bit more meaningful than the CSF, especially for nice clean armchair calculations and tank testing. However, is it really useful under practical conditions? To answer this question it helps to do some offshore sailing AND go on board of lots of offshore cruising vessels, as I have had the privilege of doing the last 10 summers, or so. Here is "the real world": The typical cruiser probably carries from 1500 to 5000 pounds in supplies, spares, equipment and toys around. None of that properly incorporated in the AVS calculations, of course. Although you are right that a prudent sailor should tie everything that is heavy down, most of us still have several hatches and floor boards that are at best "lightly secured" and not necessarily able to withstand a violent rollover (as many accounts of actual capsizes by VERY experienced sailors will attest to). However, for the sake of argument, let's assume all the supplies and spares stay in place. Last time I checked, however, nobody had yet found a way to tie the water or the fuel in the tanks down. Most cruisers carry anywhere from 150 to 500 gallons of that stuff, i.e. anywhere from 1000 to well over 3000 pounds. Then there are typically anywhere from 2-6 150 pound bodies to fly around between the cabin floor and the coach roof..... O yeah, before I forget, was that AVS calculated with jib and main up and, if so, set at what angle? Was the boom lashed down or swinging around? The main problem, of course, is that the AVS is purely a static measurement in that it tries to predict what an (imaginary clean and lean) vessel would do when released at a given angle of heel. In reality, when the vessel arrives at that angle, there will be a universe of dynamic, i.e. velocity- and acceleration-dependent, inertial as well as friction forces at work that decide what really happens. When "The Great American" catamaran (with Hunter icon Steve Pettengill on board, if I remember well) capsized near Cape Horn and was floating upside down, a big wave righted the catamaran again against all AVS predictions. Why???? REAL-WORLD DYNAMICS, my un-disingenuous friend! Have fun Flying Dutchman "Rivendel II"
In fact, because of limited time right now, let me just try to give Terry some more food for thought: No question that the AVS is a little bit more meaningful than the CSF, especially for nice clean armchair calculations and tank testing. However, is it really useful under practical conditions? To answer this question it helps to do some offshore sailing AND go on board of lots of offshore cruising vessels, as I have had the privilege of doing the last 10 summers, or so. Here is "the real world": The typical cruiser probably carries from 1500 to 5000 pounds in supplies, spares, equipment and toys around. None of that properly incorporated in the AVS calculations, of course. Although you are right that a prudent sailor should tie everything that is heavy down, most of us still have several hatches and floor boards that are at best "lightly secured" and not necessarily able to withstand a violent rollover (as many accounts of actual capsizes by VERY experienced sailors will attest to). However, for the sake of argument, let's assume all the supplies and spares stay in place. Last time I checked, however, nobody had yet found a way to tie the water or the fuel in the tanks down. Most cruisers carry anywhere from 150 to 500 gallons of that stuff, i.e. anywhere from 1000 to well over 3000 pounds. Then there are typically anywhere from 2-6 150 pound bodies to fly around between the cabin floor and the coach roof..... O yeah, before I forget, was that AVS calculated with jib and main up and, if so, set at what angle? Was the boom lashed down or swinging around? The main problem, of course, is that the AVS is purely a static measurement in that it tries to predict what an (imaginary clean and lean) vessel would do when released at a given angle of heel. In reality, when the vessel arrives at that angle, there will be a universe of dynamic, i.e. velocity- and acceleration-dependent, inertial as well as friction forces at work that decide what really happens. When "The Great American" catamaran (with Hunter icon Steve Pettengill on board, if I remember well) capsized near Cape Horn and was floating upside down, a big wave righted the catamaran again against all AVS predictions. Why???? REAL-WORLD DYNAMICS, my un-disingenuous friend! Have fun Flying Dutchman "Rivendel II"
Probably Fine
I own a 35.5 [1992] and have sailed in some pretty rough water in the Atlantic albeit 25 miles offshore. I thinbk the boat is beefy enough to take it. By the way the capsize screen ia 1.9 which is on the positive side of the 2.0 calculation ocean racers use as their measurement of ultimate righting / stability. From what I hear from a number of old salts about ocean crossings, is that the boat is only secondary to the skill and seamanship knowledge of the sailor AND the time of year it is attempted. That's probably accurate in that people have crossed the ocean in little more than a canoe. The counter agrument is that even in a ship you are probably at risk in the Bering Sea in the winter. So choose your time and place of crossing carefully, and don't forget the emergency stuff. Fred Miller S/V M Squared
I own a 35.5 [1992] and have sailed in some pretty rough water in the Atlantic albeit 25 miles offshore. I thinbk the boat is beefy enough to take it. By the way the capsize screen ia 1.9 which is on the positive side of the 2.0 calculation ocean racers use as their measurement of ultimate righting / stability. From what I hear from a number of old salts about ocean crossings, is that the boat is only secondary to the skill and seamanship knowledge of the sailor AND the time of year it is attempted. That's probably accurate in that people have crossed the ocean in little more than a canoe. The counter agrument is that even in a ship you are probably at risk in the Bering Sea in the winter. So choose your time and place of crossing carefully, and don't forget the emergency stuff. Fred Miller S/V M Squared
Chewing on Henk's food
I'm not a naval architect. what assumptions might or might not be made in stability computations only the person making the calculation in a particular situation could say. Still it would seem to me more reasonable that a reasonable naval architect would make his computations with an assumption of stores on the boat than to make it with an assumption of no stores as Henk assumes. Tankage is a non issue, assuming the tanks stay in place. For a full tank, the center of gravity for each tank will stay the same whatever the boat angle of heel. Likewise boom position and sail deployment is less than pertinent for capsize conditions, the area of interest for the AVS. Anything over 90 degrees has at least the mast top in the water, probably providing some positive buoyancy and righting moment as it sinks further with increasing angle. Attached is a photo of Isabelle Autessier's PRB happily floating quite stable upside down in the southern ocean after a capsize during the 1998 Around Alone race. Why??? I'd rather depend on engineering computations that say a boat will come back upright after a capsize than depend on some vagary of a wave train to set an unstable boat back upright. Engineering design is always done with assumptions. That these assumptions don't perfectly mirror the real world is not an argument to go back to spells and incantations to keep a boat safe.
I'm not a naval architect. what assumptions might or might not be made in stability computations only the person making the calculation in a particular situation could say. Still it would seem to me more reasonable that a reasonable naval architect would make his computations with an assumption of stores on the boat than to make it with an assumption of no stores as Henk assumes. Tankage is a non issue, assuming the tanks stay in place. For a full tank, the center of gravity for each tank will stay the same whatever the boat angle of heel. Likewise boom position and sail deployment is less than pertinent for capsize conditions, the area of interest for the AVS. Anything over 90 degrees has at least the mast top in the water, probably providing some positive buoyancy and righting moment as it sinks further with increasing angle. Attached is a photo of Isabelle Autessier's PRB happily floating quite stable upside down in the southern ocean after a capsize during the 1998 Around Alone race. Why??? I'd rather depend on engineering computations that say a boat will come back upright after a capsize than depend on some vagary of a wave train to set an unstable boat back upright. Engineering design is always done with assumptions. That these assumptions don't perfectly mirror the real world is not an argument to go back to spells and incantations to keep a boat safe.
Attachments
Crossing
Terry A. Great post, makes a lot of sense! Great photo too. Am I correct in assuming that she had a cantilevered keel?
Terry A. Great post, makes a lot of sense! Great photo too. Am I correct in assuming that she had a cantilevered keel?
Chewing Terry's cud a little further...
Terry, your first argument that "a reasonable naval architect would make his computations with an assumption of stores on the boat" doesn't address the all-important question of: (a) how many thousands of pounds and (b) where stored. Whether or not your hypothetical architect included some assumed values in his calculations or not, the unavoidable range of variation is clearly very large. Your second argument "tankage is a non issue, assuming the tanks stay in place. For a full tank, the center of gravity for each tank will stay the same whatever the boat angle of heel" is simply wrong. Assuming that the average vessel uses both water and fuel as it makes a passage but carries a 50% excess of both as a buffer for unanticipated setbacks, average tank levels underway will be about 2/3 full. With a typical tank height in the 3-5 foot range the average drop in center of gravity (for several thousands of pounds in tankage fluids) will be well over a foot by the time the vessel fully capsizes. Worse than that, of course, may be the inertial forces of the sloshing fluids (even though partially tempered by small baffles in the better constructed tanks). Your argument about sails and boom is unclear to me. Are you arguing that it does not make any difference to the AVS? From a dynamic point of view, whether the sails are up or not is going to make a tremendous difference once they hit the water, immediately followed by the question whether or not the rig will hold or fold, of course..... To my everlasting disappointment you did not even attempt to chew on the "dynamic" food I offered; i.e. the question of the value of any simplistic static model in a highly dynamic situation. There is simply no good way of incorporating these dynamic considerations into a stability model, unless one would be able to conduct large-scale controlled experiments designed to span the inherently high-dimensional parameter envelope of a vessel capsize in rough seas. In all empirical modeling efforts of complex phenomena the rule of thumb is that the number of available data points has to be several times that of the major dimensions of the parameter space. Although I am not a naval architect either, much of my research work is about exploring high-dimensional parameter spaces and the thought of anyone trying to design a simple static model for a vessel capsize in rough seas is enough to make my skin crawl. Have a great day! Henk Meuzelaar BTW: My closest associate here at the UofU is a great guy by the name of Neil Arnold, a physicist. Might he be a relative of yours?
Terry, your first argument that "a reasonable naval architect would make his computations with an assumption of stores on the boat" doesn't address the all-important question of: (a) how many thousands of pounds and (b) where stored. Whether or not your hypothetical architect included some assumed values in his calculations or not, the unavoidable range of variation is clearly very large. Your second argument "tankage is a non issue, assuming the tanks stay in place. For a full tank, the center of gravity for each tank will stay the same whatever the boat angle of heel" is simply wrong. Assuming that the average vessel uses both water and fuel as it makes a passage but carries a 50% excess of both as a buffer for unanticipated setbacks, average tank levels underway will be about 2/3 full. With a typical tank height in the 3-5 foot range the average drop in center of gravity (for several thousands of pounds in tankage fluids) will be well over a foot by the time the vessel fully capsizes. Worse than that, of course, may be the inertial forces of the sloshing fluids (even though partially tempered by small baffles in the better constructed tanks). Your argument about sails and boom is unclear to me. Are you arguing that it does not make any difference to the AVS? From a dynamic point of view, whether the sails are up or not is going to make a tremendous difference once they hit the water, immediately followed by the question whether or not the rig will hold or fold, of course..... To my everlasting disappointment you did not even attempt to chew on the "dynamic" food I offered; i.e. the question of the value of any simplistic static model in a highly dynamic situation. There is simply no good way of incorporating these dynamic considerations into a stability model, unless one would be able to conduct large-scale controlled experiments designed to span the inherently high-dimensional parameter envelope of a vessel capsize in rough seas. In all empirical modeling efforts of complex phenomena the rule of thumb is that the number of available data points has to be several times that of the major dimensions of the parameter space. Although I am not a naval architect either, much of my research work is about exploring high-dimensional parameter spaces and the thought of anyone trying to design a simple static model for a vessel capsize in rough seas is enough to make my skin crawl. Have a great day! Henk Meuzelaar BTW: My closest associate here at the UofU is a great guy by the name of Neil Arnold, a physicist. Might he be a relative of yours?
1/4-inch Plexiglass
The hatches on the Hunters of that vintage are only 1/4-inch plexiglass set in some soft stuff surrounded by a thin aluminum extruded frame mounted with four, probably #10 screws, to the frame. Talking about ratios is fine but is a 24-inch square foredeck hatch going to take a wave? One cubic foot of water is 62.4 pounds and that is sitting still. How much does several feet of water weigh? Suppose the boat learched and took a good wave, would the hatch be strong enough to stand it? Look at all the stuff people have hanging on their stern rail. Ever seen how the pushpit is attached? What about a single 1/4-inch bolt per vertical tube. And how many people run around with davits holding their inflatable and the only thing holding the whole thing up are a few 1/4-inch bolts? Take a blue-water wave here and you loose the inflatable, man-overboard gear, barbacue, horseshoe, outboard, solar pannels, and who knows what else. The 35 is a good boat but mine is only 12,600 pounds, I like it, it sails really well, gota a storm jib but and I wouldn't want to take it through some of the conditions that Lin and Larry Pardy took theirs. The MAIN thing is the human behind the wheel (or tiller). Smart decisions or DUMB decisions, which will it be? Hell, even the guy who sailed the Titanic sent her to the bottom! Probably a bigger boat that all of ours put together. Think about that!
The hatches on the Hunters of that vintage are only 1/4-inch plexiglass set in some soft stuff surrounded by a thin aluminum extruded frame mounted with four, probably #10 screws, to the frame. Talking about ratios is fine but is a 24-inch square foredeck hatch going to take a wave? One cubic foot of water is 62.4 pounds and that is sitting still. How much does several feet of water weigh? Suppose the boat learched and took a good wave, would the hatch be strong enough to stand it? Look at all the stuff people have hanging on their stern rail. Ever seen how the pushpit is attached? What about a single 1/4-inch bolt per vertical tube. And how many people run around with davits holding their inflatable and the only thing holding the whole thing up are a few 1/4-inch bolts? Take a blue-water wave here and you loose the inflatable, man-overboard gear, barbacue, horseshoe, outboard, solar pannels, and who knows what else. The 35 is a good boat but mine is only 12,600 pounds, I like it, it sails really well, gota a storm jib but and I wouldn't want to take it through some of the conditions that Lin and Larry Pardy took theirs. The MAIN thing is the human behind the wheel (or tiller). Smart decisions or DUMB decisions, which will it be? Hell, even the guy who sailed the Titanic sent her to the bottom! Probably a bigger boat that all of ours put together. Think about that!
Agree about the need for reinforcements
Our preparation list (for a Legend 43) included the following reinforcements and redundant systems: - 1/2 inch tinted Lexan for all acrylic hatches and windows - 4 hatch-mounted dorade boxes - ss support bars under the larger Lexan cabin windows - heavy ss knees to reinforce the cabin roof - heavy ss tangs to reinforce the pushpit - integrated ss stemplate/bowsprit for 2 anchors - reinforced windlass mount - inner forestay with rollerfurling staysail - running backstays - 2 additional selftailing cockpit winches - two whiskerpoles - Autohelm windvane with accessory rudder - strongly reinforced davits plus solar panel mounts - radar pole and SSB whip on pushpit - CARD radar detector (useless toy) - GPS systems (1 mounted; 1 hand) - deep lazarette (using up part of the aft cabin) - Paratech sea anchor - Galerider drogue - Tinker Star traveler with inflatable canopy - 406 Mhz Epirb - hard boomvang - dodger with big handles to climb in and out of cockpit - big handle on pedestal behind steering wheel - Galesail type stormjib - 3rd reef points on main - spare main and genoa - hermetically sealed propane locker - locking handles on floorboards - double bilge pumps and alarms I am sure that I am forgetting at least half a dozen smaller or larger modifications without which we would not feel nearly as secure. On the other hand, many of these reinforcements I would have had to install on nearly any other new vessel. Alas, I should add that the newer Hunter models do have such small anchor lockers, plus a lack of toerails and potentially usable seabunks, that I have told the admiral "no way am I ever going to try and modify these for offshore work", even though on boat shows she consistently picks the Passage 420 as her favorite future vessel (from among a wide range of other models and brands). Flying Dutchman "Rivendel II"
Our preparation list (for a Legend 43) included the following reinforcements and redundant systems: - 1/2 inch tinted Lexan for all acrylic hatches and windows - 4 hatch-mounted dorade boxes - ss support bars under the larger Lexan cabin windows - heavy ss knees to reinforce the cabin roof - heavy ss tangs to reinforce the pushpit - integrated ss stemplate/bowsprit for 2 anchors - reinforced windlass mount - inner forestay with rollerfurling staysail - running backstays - 2 additional selftailing cockpit winches - two whiskerpoles - Autohelm windvane with accessory rudder - strongly reinforced davits plus solar panel mounts - radar pole and SSB whip on pushpit - CARD radar detector (useless toy) - GPS systems (1 mounted; 1 hand) - deep lazarette (using up part of the aft cabin) - Paratech sea anchor - Galerider drogue - Tinker Star traveler with inflatable canopy - 406 Mhz Epirb - hard boomvang - dodger with big handles to climb in and out of cockpit - big handle on pedestal behind steering wheel - Galesail type stormjib - 3rd reef points on main - spare main and genoa - hermetically sealed propane locker - locking handles on floorboards - double bilge pumps and alarms I am sure that I am forgetting at least half a dozen smaller or larger modifications without which we would not feel nearly as secure. On the other hand, many of these reinforcements I would have had to install on nearly any other new vessel. Alas, I should add that the newer Hunter models do have such small anchor lockers, plus a lack of toerails and potentially usable seabunks, that I have told the admiral "no way am I ever going to try and modify these for offshore work", even though on boat shows she consistently picks the Passage 420 as her favorite future vessel (from among a wide range of other models and brands). Flying Dutchman "Rivendel II"
I'm Impressed Henk!
That's the kind of additions I would want too. Takes a few bucks and lots of thought to outfit a boat for cruising. And I'll bet there are still some things you want - right? And I agree with you on the new "toe rails". The extruded aluminum ones are low enough but at least there is a bit of tooth there for a deck shoe to grab onto. I'd feel more comfortable if they would extrude them a little higher - think mine are about 1.5 inches or so. The raised gel coat lip is just too small and slippery. -= John =-
That's the kind of additions I would want too. Takes a few bucks and lots of thought to outfit a boat for cruising. And I'll bet there are still some things you want - right? And I agree with you on the new "toe rails". The extruded aluminum ones are low enough but at least there is a bit of tooth there for a deck shoe to grab onto. I'd feel more comfortable if they would extrude them a little higher - think mine are about 1.5 inches or so. The raised gel coat lip is just too small and slippery. -= John =-
Great List, Henk!
That's the voice of experience, and adds real value for us all. David Lady Lillie
That's the voice of experience, and adds real value for us all. David Lady Lillie
How to select a design for offshore?b
Preparations for blue/green water cruising offshore include crew, strength, stowage, comfort, systems, safety, etcetera. But if we look at design, how can we judge the good ones? How can we understand the risk we take if we select a less stable boat, and make it even less stable by the way we load and equip it? In my navy training, we were told that "the Navy Regs are written in blood." That meant that most of our regulations resulted from the lessons learned when someone died by doing the opposite. For us sailors, these lessons come from the times that storms strike fleets of boats, and some lose crews or the boats itself. Books like Heavy Weather examine the boats that failed, and the survivors. The leading cause of loss of life and or boats is inadequate stability, measured by Angle of Vanishing Stability (AVS) (also called the Limit of Positive Stability.) These conclusions _have_ been exhaustively tested and verified with different hull shapes in test tanks. Other causes include hull strength, failure of safety gear (or failure to use it), and getting the boat broadside to the waves. This last is most often caused by exhaustion of the crew who are sheltered in the cabin while the boat is unable to heave to, or a drogue device is not effectively deployed. Boats that take the waves end on are seldom inverted, although it has happened. "Traditional" designs reflected the realities of taking boats to sea interpreted by great designers. Most of the "classic plastic" designs of the 70's reflect these moderate and balanced principles. The Cherubini Hunters are excellent examples, but a number of others can be named. Most of these designs are well suited to offshore sailing. Whether they are strong enough or prepared enough is another question. Starting in the 80's, production boat designers began to alter designs to make them faster in light winds, give them more accommodation room, make them more convenient and easier to sail, and lower their real cost. Some of these changes are just good design for any conditions, but most of them make a boat less likely to survive, and take care of its crew in a severe storm. (Severe storms have occurred almost every where, and at any time. It' true we can choose times when they are (even much) less likely, but most of the storms that caused large numbers of losses were somehow un-seasonal, or unexpected.) The AVS (or the Capsize Screening Formula if AVS is not available) is consistently used by the experts who examine results of these storms to descriminate the survivors from the losses. The AVS _is_ dynamic. It tells us the force the boat is exerting to right itself, or hold itself inverted in the waves and wind. Of course, it doesn't include the impact of waves and wind, or how we load our boats. The waves and wind are the problem, and it is our choice whether we increase or decrease stability with our loading. I've attached an analysis of Henk's variables for an example. So, I would use AVS, hull shape, capsize screen, and analysis by real designers to pick a hull for offshore cruising. And I would want to know the approximate risks I am taking if I choose a less suitable design, or decrease its stability with loading. David Lady Lillie Analysis of Henk's variations: "The typical cruiser probably carries from 1500 to 5000 pounds in supplies, spares, equipment and toys around." - If these are securely stowed low in the cabin they improve stability, otherwise, they decrease it. "Although you are right that a prudent sailor should tie everything that is heavy down, most of us still have several hatches and floor boards that are at best "lightly secured" and not necessarily able to withstand a violent rollover..." If it moves, it will go to the lowest point of the cabin - this almost always reduces the AVS. "Last time I checked, however, nobody had yet found a way to tie the water or the fuel in the tanks down. Most cruisers carry anywhere from 150 to 500 gallons of that stuff, i.e. anywhere from 1000 to well over 3000 pounds." The problem of liquids is defined by the "free surface area" they have. A full tank low in the hull has no free surface and contributes positively to stability. A partially full tank is slightly less stable, but the effect is limited by the size of the tank, and the net effect is still positive unless the tank breaks loose. "Then there are typically anywhere from 2-6 150 pound bodies to fly around between the cabin floor and the coach roof....." Crew on the cabin benches or the windward wide of the boat increase stability. Otherwise they decrease it. For a small cruising crew of two or four, we really don't play much of a role. All of the stuff we mount on the decks and rigging decrease stability when rolling, although they do increase initial resistance to roll forces. Once the boat is heeled at 90 degrees (a knockdown), _all_ of this weight is pulling the boat over towards inverted and holding it there, even if it does slow the rate of roll as it moves through the water.
Preparations for blue/green water cruising offshore include crew, strength, stowage, comfort, systems, safety, etcetera. But if we look at design, how can we judge the good ones? How can we understand the risk we take if we select a less stable boat, and make it even less stable by the way we load and equip it? In my navy training, we were told that "the Navy Regs are written in blood." That meant that most of our regulations resulted from the lessons learned when someone died by doing the opposite. For us sailors, these lessons come from the times that storms strike fleets of boats, and some lose crews or the boats itself. Books like Heavy Weather examine the boats that failed, and the survivors. The leading cause of loss of life and or boats is inadequate stability, measured by Angle of Vanishing Stability (AVS) (also called the Limit of Positive Stability.) These conclusions _have_ been exhaustively tested and verified with different hull shapes in test tanks. Other causes include hull strength, failure of safety gear (or failure to use it), and getting the boat broadside to the waves. This last is most often caused by exhaustion of the crew who are sheltered in the cabin while the boat is unable to heave to, or a drogue device is not effectively deployed. Boats that take the waves end on are seldom inverted, although it has happened. "Traditional" designs reflected the realities of taking boats to sea interpreted by great designers. Most of the "classic plastic" designs of the 70's reflect these moderate and balanced principles. The Cherubini Hunters are excellent examples, but a number of others can be named. Most of these designs are well suited to offshore sailing. Whether they are strong enough or prepared enough is another question. Starting in the 80's, production boat designers began to alter designs to make them faster in light winds, give them more accommodation room, make them more convenient and easier to sail, and lower their real cost. Some of these changes are just good design for any conditions, but most of them make a boat less likely to survive, and take care of its crew in a severe storm. (Severe storms have occurred almost every where, and at any time. It' true we can choose times when they are (even much) less likely, but most of the storms that caused large numbers of losses were somehow un-seasonal, or unexpected.) The AVS (or the Capsize Screening Formula if AVS is not available) is consistently used by the experts who examine results of these storms to descriminate the survivors from the losses. The AVS _is_ dynamic. It tells us the force the boat is exerting to right itself, or hold itself inverted in the waves and wind. Of course, it doesn't include the impact of waves and wind, or how we load our boats. The waves and wind are the problem, and it is our choice whether we increase or decrease stability with our loading. I've attached an analysis of Henk's variables for an example. So, I would use AVS, hull shape, capsize screen, and analysis by real designers to pick a hull for offshore cruising. And I would want to know the approximate risks I am taking if I choose a less suitable design, or decrease its stability with loading. David Lady Lillie Analysis of Henk's variations: "The typical cruiser probably carries from 1500 to 5000 pounds in supplies, spares, equipment and toys around." - If these are securely stowed low in the cabin they improve stability, otherwise, they decrease it. "Although you are right that a prudent sailor should tie everything that is heavy down, most of us still have several hatches and floor boards that are at best "lightly secured" and not necessarily able to withstand a violent rollover..." If it moves, it will go to the lowest point of the cabin - this almost always reduces the AVS. "Last time I checked, however, nobody had yet found a way to tie the water or the fuel in the tanks down. Most cruisers carry anywhere from 150 to 500 gallons of that stuff, i.e. anywhere from 1000 to well over 3000 pounds." The problem of liquids is defined by the "free surface area" they have. A full tank low in the hull has no free surface and contributes positively to stability. A partially full tank is slightly less stable, but the effect is limited by the size of the tank, and the net effect is still positive unless the tank breaks loose. "Then there are typically anywhere from 2-6 150 pound bodies to fly around between the cabin floor and the coach roof....." Crew on the cabin benches or the windward wide of the boat increase stability. Otherwise they decrease it. For a small cruising crew of two or four, we really don't play much of a role. All of the stuff we mount on the decks and rigging decrease stability when rolling, although they do increase initial resistance to roll forces. Once the boat is heeled at 90 degrees (a knockdown), _all_ of this weight is pulling the boat over towards inverted and holding it there, even if it does slow the rate of roll as it moves through the water.
David's "coastal" vs. "offshore" vessel distinction
IMHO, this distinction is nearly useless as a vessel design classifyer because of the enormous range of different coastal and offshore conditions encountered, particularly at different latitudes and in different seasons. Instead, "coastal" vs. "offshore" has far more to do with how vessel and crew are prepared. Starting out from Maine or Seattle (or even from San Francisco and Chesapeake Bay) and following the respective coastlines down to the Tropic of Cancer before making the offshore passage to one's favorite bluewater destination, sailing vessels are going to enounter their toughest design challenges during the coastal leg more than 90 % of the time, even if picking the best possible time for each leg. Just study the pilot charts and talk to the sailors who have actually done this. Moreover, many sailors will prefer to leave their vessels in its destination area for several seasons, obviating the need to make this long and tricky coastal "trek" every year, However, when eventually coming back, the infamous "upwind Baja bash" for left coast sailors is often exaggerated because of the poor upwind capability of many older vessels. Although I have not made the passage back from the Caribbean myself strongly suspect that sailors with modern vessels have little to learn (or fear) from Bruce van Sant's "Gentlemen Don't Sail to Windward" advice. Instead, study the pilot charts, talk to other sailors and then pick your own best route. If we would have followed "Charlie's Charts" advice on how to sail back to the US mainland from Hawaii, or Jimmy Cornell's "World Cruising Routes" advice to sail to Vanuatu from Cairns ("don't even consider sailing this route directly") and thus have chosen to go through higher latitudes to make our Easting, we would have needlessly exposed ourselves to the frequent strong gales in these regions. As it turned out (in both cases) we made pretty fast upwind passages which were more stimulating than exhausting, while some of our cruising friends without the upwind option had to sail a lot further AND slug it out with the gales. Have fun! Flying Dutchman BTW Just a handful of miles from Mentor Lagoons the 440 ton wooden barge "David Foster" rests on the bottom of Lake Erie since 1936 (see link)! Might this have some connection to your cautious approach to sailing? :0))
IMHO, this distinction is nearly useless as a vessel design classifyer because of the enormous range of different coastal and offshore conditions encountered, particularly at different latitudes and in different seasons. Instead, "coastal" vs. "offshore" has far more to do with how vessel and crew are prepared. Starting out from Maine or Seattle (or even from San Francisco and Chesapeake Bay) and following the respective coastlines down to the Tropic of Cancer before making the offshore passage to one's favorite bluewater destination, sailing vessels are going to enounter their toughest design challenges during the coastal leg more than 90 % of the time, even if picking the best possible time for each leg. Just study the pilot charts and talk to the sailors who have actually done this. Moreover, many sailors will prefer to leave their vessels in its destination area for several seasons, obviating the need to make this long and tricky coastal "trek" every year, However, when eventually coming back, the infamous "upwind Baja bash" for left coast sailors is often exaggerated because of the poor upwind capability of many older vessels. Although I have not made the passage back from the Caribbean myself strongly suspect that sailors with modern vessels have little to learn (or fear) from Bruce van Sant's "Gentlemen Don't Sail to Windward" advice. Instead, study the pilot charts, talk to other sailors and then pick your own best route. If we would have followed "Charlie's Charts" advice on how to sail back to the US mainland from Hawaii, or Jimmy Cornell's "World Cruising Routes" advice to sail to Vanuatu from Cairns ("don't even consider sailing this route directly") and thus have chosen to go through higher latitudes to make our Easting, we would have needlessly exposed ourselves to the frequent strong gales in these regions. As it turned out (in both cases) we made pretty fast upwind passages which were more stimulating than exhausting, while some of our cruising friends without the upwind option had to sail a lot further AND slug it out with the gales. Have fun! Flying Dutchman BTW Just a handful of miles from Mentor Lagoons the 440 ton wooden barge "David Foster" rests on the bottom of Lake Erie since 1936 (see link)! Might this have some connection to your cautious approach to sailing? :0))
So, Henk, just take any design?
The most recent edition of Adlards Heavy Weather considers some lighter, more weatherly , modern designs as good yachts for offshore work. (Your boat is one such, considering your preparations.) I think the issue is actually the ability of the boat to take care of the crew in an extended period of dangerous (versus tough) conditions including breaking waves that could capsize the boat lasting for days. In the coastal areas of North America, including our Great Lakes, we can have horrendous weather. But a safe port is usually available before the total exhaustion of the crew (20 hours is a reasonable number.) Finally, I am not pushing conservative strategy. I am encouraging our group to understand the implications of the boat design they choose to sail - to understand their risks, and have realistic contingency plans. Finally, I feel a lillte foolish holding out so long against a guy who has done it when I have not. But your luck in missing a severe storm in the trade wind regions doesn't mean they don't occur. Seriously, what advice would you give us in picking a design to cross an ocean? Will any design do? David Lady Lillie
The most recent edition of Adlards Heavy Weather considers some lighter, more weatherly , modern designs as good yachts for offshore work. (Your boat is one such, considering your preparations.) I think the issue is actually the ability of the boat to take care of the crew in an extended period of dangerous (versus tough) conditions including breaking waves that could capsize the boat lasting for days. In the coastal areas of North America, including our Great Lakes, we can have horrendous weather. But a safe port is usually available before the total exhaustion of the crew (20 hours is a reasonable number.) Finally, I am not pushing conservative strategy. I am encouraging our group to understand the implications of the boat design they choose to sail - to understand their risks, and have realistic contingency plans. Finally, I feel a lillte foolish holding out so long against a guy who has done it when I have not. But your luck in missing a severe storm in the trade wind regions doesn't mean they don't occur. Seriously, what advice would you give us in picking a design to cross an ocean? Will any design do? David Lady Lillie
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