Seaworthiness

Discussion in 'Stability' started by Guillermo, Nov 26, 2006.

  1. RHough
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    RHough Retro Dude

    Thank you. I think this will be a good test ... all in good fun. :)

    I know that there are others that will be interested in the results. We both know that any one passage won't be proof of concept either way, but it should serve to showcase the methods available to today's cruiser.
     
  2. hiracer
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    hiracer Senior Member

    Actually I agree. I plan to carry both, and use mainly the unitary drogue. The series drogue will be deployed only when all else fails, I'm injured, or pitchpoling is a serious risk during a survival storm. I agree with the bias in favor of an active response to a storm but also recognize that an active response is not always possible, especially in light of the possibility of being injured or vital equipment breaking.

    I suspect that this anticipation of the impossibility of an active response to a storm, and conversely the inability/refusal to anticipate such a development, underpins the bias against and for modern sailboat design. The adherents of modern lightweight sailboat design will go to great lengths to deny the possibility of any situation where the boat must look after captian and crew, because they have to.

    I like the analogy of riding a motorcycle, the lack of air bags and inherent instability of only two wheels causing one to be more careful. Where the analogy breaks down, of course, is that one can stop a motorcycle under an underpass when the weather gets really bad and wait it out (a passive approach, BTY) while in a cruising boat you are stuck in it, for better or worse, no getting off on dry land to wait it out. And if you do it right, a motorcycle never sinks. :)
     
  3. Guillermo
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    Guillermo Ingeniero Naval

    Randy,
    I have not forgotten you. I am thinking what could be a fair proposal, not too bizarre or absurd.

    Maybe something like a leg from The Solent (UK) to the Canary islands non-stop (1500+ miles), as previous to an Atlantic crossing, or either a Bermuda-Azores (Horta) one (1900 miles), when coming back to Europe.

    Let's say you're an UK citizen (university professor?) in a sabbatic year and you plan to do the going and coming back within your available one year time. You're planning to have a once-in-a-lifetime adventure spending several months in the Caribbean, and go with your wife and your 12-14 year old kids, so you have to wait at least to August for the departure, and be back at work by the first days of September next year.

    To make the first leg in a row makes little sense, I know, because the usual thing should be to stop somewhere along the Iberian peninsula's west coast (more than once), but then the distances would be too short to our purposes.

    You'd have to allow for some slowing down when encountering head winds and waves, as those may significatively affect the speed of the boat. How can we manage that? What could be a not too complicated estimative for that? Perhaps dropping speed in an increasing percentage with increasing head wind forces?

    The bad thing is that to check the real weather for such routes we'll have to wait to the corresponding times of the year. If we want to go ahead with the test within the next weeks (not to wait too long), we could also think in another 'role', as the one of a delivery crew of 3 sailing a client's boat from the Canary islands to the UK (that lucky guy found a nice deal for a boat there when visiting the islands last summer! ;) ) and the later time to do such trip should be May-June (As a matter of fact a relative of mine is planning to come from the Canaries to Galicia about that time).

    What do you think? Any other idea from you or another fellow poster? Maybe a Pacific crossing from the States?

    Cheers.
     
  4. KevlarPirate
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    KevlarPirate Junior Member

    “This man is probably wealthier than you and therefore according to your ideas he is a superior being, so his ideas can't be too far out.”

    Sorry to have gotten under your skin , however small statistical samples usually lead to wrong conclusions. You seem to rely on them frequently. This thread has a lot to do with physics, more specifically statics and dynamics.
    The picture I posted clearly shows a boat having been very easily overpowered and having most all of it’s hull floating above the water exposing the control surfaces to air not water. A quantum jump of impedance mismatch of over 800 to 1. And resulted in a totally helpless condition.
    Any first year physics student can see that; the picture tells a thousand words. The boat was well reefed and probably doing well and then lost control with a gust or wave, either one being a small input which put it into an out of control situation. It is obvious that it is not in storm conditions as the ocean is pretty flat and wind gusts were probably benign.

    Storm situations create highly variable inputs (a very high standard deviation) very much unlike what the picture shows. Cruising boats are designed to withstand large variables, not fly out of control with just a little push to put it over the top.
    If you see that picture and can somehow argue that is a safe offshore platform, then we have nothing more to say. That boat in a big breaking wave would be a death trap.
    My point was that Fastnet showed how NOT to design boats for offshore and that unfortunately has been ignored. The fact is that boat and many more were designed after the lessons were supposedly learned , I don’t care if it was one month, 9 years or 100 years.

    The point, which is being clearly missed, is that light weight boats like these are excellent for racing in venues like Key West Race Week and similar, but to convince yourself that they are safe offshore boats is a delusion. A total joke!
    If you were to ask me to insure one of them I would charge as the premium the full cost of the boat and then some for profit after I have to pay for the disaster, and for that matter so would you.

    Retro , you keep avoiding the issues I bring up

    You are half way to Bermuda in 4 knots of wind and your weather router informs you a storm in has developed and approaching from the west, doing 450 miles a day and your weather will be seeing deteriorating conditions within 12 hours. Please tell me how you are going to get out of that.

    Most boat losses are a result of groundings on reefs and rocks.
    You are grounded. Your perfect electronics was held hostage by the combination of a small cross current which you couldn’t detect and a small inaccuracy in your chart. How is your 5mm thick hull going to survive being pulled off?

    The second most frequent loss of boats has to do with collisions in open water. Please tell me how a 5mm skin thickness will do better than ¾ inch of solid glass or 3/8ths of aluminum.? Against the corner of a container floating 6 inches above the water. Your forward looking sonar was working perfectly but you didn’t see it because your attention was reduced from 100% to 98% and that was the 2 %.

    How do you survive never getting injured or your capacity to keep the boat going 15 kts (in that 4 knots of wind)?


    I have heard your pitch now several times (weather routing) and complicated electronics which never fail. but I would really like to know how you are going to avoid all of the common problems cruisers encounter regularly.
    You talk of airplanes but you don’t mention 4x system redundancy to overcome single point failures. You also don’t mention that a platform like a F-16 is an unstable platform therefore can’t glide on it’s own and therefore has an ejection seat. (that is it's safety valve because the design cannot offer a solution)

    Clearly Mr. CT is not happy with my statements regarding superiority (which he unfortunately took personally),
    However, I think you should be the one he is questioning because you are not going to have to go through the hard knocks that all of us had to. That would truly be superior.
    As I said before, I admire your enthusiasm and your theories may create encouragement, but I have a problem with the forces which are beyond your control. You keep selling that there are no situations which cannot be avoided with proper preparation and that as a result , you can reduce safety margins in other areas. That seems very risky for the biggest reason is that it takes all of your solutions to be in place and working properly all the time.
    Complex solutions are more failure prone than simple solutions. When any of your proactive or reactive tools fail, you have no safety net you can limp into.
    My question above about how you plan to escape voids only one of your necessary ingredients (hull speed), so now you are in plan B which means you are going to have to go through it just like everyone else but you will be in a minimalistic boat way more at the mercy of the elements.
    So fine be my guest! Do it and you will also write the stories you claim only the Westsail guys write.

    I came into this thread mostly for the benefit of readers other than yourselves; I am not trying to change your minds. Others will decide based on what they read here and then go on to find other data reaching far beyond annecdotes. There is much published about this by people with technical backgrounds. It is out there. My mission here is complete.
     
  5. KevlarPirate
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    KevlarPirate Junior Member

    sorry, I missed this

    “It's probably not worth trying to be logical with someone who brags about the fact that his wealth proves that he comes from a "superior gene pool" than mere "lesser people", but your facts about the Fastnet are incorrect, as R Hough pointed out.”


    You deliberately misrepresented my statement, but you give me another chance to point a finger at those with the “entitlement disease” so thanks. My statement had NOTHING to do with myself or bragging, but everything to do with people who think that they should be allowed every luxury the wealthy. And yes, it is the rule is that people become wealthy because they ARE smarter and work harder than the rest and they should be able to freely enjoy those luxuries without being punished through taxes to take care of freeloaders. Swallow the pill! It is the exception that you are born sitting on an oil well.

    As for my Fastnet statement I agree with you, I was incorrect.
    “15 deaths, 19 boats abandoned, 5 boats sank, 306 boats started. That makes "many" = less than 2%?”
    I should have said TOO MANY, sorry. And obvously to you, those deaths were all on boats which the owners probably thought were much safer then they had been deluded into thinking in light of your statement that they knew the storm was comming.

    Retro that was a really arogant statement about 2 %,
    It is also incorrect since pretty much all of the fleet which were on the shelf at the time things got really bad were the small guys and they all got beat up pretty bad.
    The friend of yours who said it really wasn't that bad was past the really dangerous area. Hell, Ted Turner won it and said "we are eating steak and others are dying out here". I have sailed against him, but I never liked him for his arrogance either.



    Maybe you would like these books..

    John Rousmaniere, ed., DESIRABLE & UNDESIRABLE CHARACTERISTICS OF OFFSHORE YACHTS. Chapters on the screening test, stability, rigs, and just about every other aspect of offshore design. Authors include many designers -- Olin and Rod Stephens, Mitch Neff, James McCurdy, Karl Kirkman, Bill Lapworth, Ted Hood, etc.

    C.A. Marchaj, SEAWORTHINESS: THE FORGOTTEN FACTOR
     
  6. CT249
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    CT249 Senior Member

    KEvlar Pirate wrote "however small statistical samples usually lead to wrong conclusions. You seem to rely on them frequently."

    Actually I have been making exactly the same point (about the tendency of small samples to mislead) at many places in this forum! I looked specifically at the boats you mentioned (Westsail 32, S&S 41, S&S 45, 1 tonner) because you had been using them specific examples.

    Fair's fair, if the "pro heavy" crowd can use specific examples to make their point surely we "pro light" brigade can be allowed to use specific examples too!

    My point is that we can find a specific example of ANY boat getting into trouble. For some reason, when a light boat gets into trouble it is taken by some people as an indication of a general problem. When a heavy boat gets into trouble, those same people will explain it away as being an isolated incident.

    The pic you posted is a classic case in point. You have looked at the single picture and come up with a tale of an unseaworthy boat. If you had looked at the series of photos in detail, you will see that the wind was pretty hairy, actually - Jameson has got a #4 and three reefs in. That's extreme for a short race, not benign.

    "Storm situations create highly variable inputs (a very high standard deviation) very much unlike what the picture shows."

    Another photo taken at the same time shows the boat heeled maybe 10 degrees, while hard on the wind. It appears that there WERE highly variable input, to get the boat from lightly heeled and under full control, to over on its ear.


    "If you see that picture and can somehow argue that is a safe offshore platform, then we have nothing more to say. That boat in a big breaking wave would be a death trap."

    Well, it depends. I admit that I was familiar with the fact that this design was off the pace upwind in a breeze. I was familar with the Soton Uni testing after Fastnet '79. So therefore, when I asked one owner about what the boat was like offshore I thought he too would have thought it was a death trap.

    However, he said that it was fine. I asked him about the low LPS and he said that in something like 7 Sydney-Hobarts (including some bad ones), a Fastnet, a One Ton Cup and many other races, he'd never got the boat heeled over to anywhere near the point where the low LPS was a factor. In contrast, he said, his first S&S boat had regularly been knocked almost flat because this popular design was notoriously hard to steer in some guises.

    Now, when someone who certainly has more experience than me, and almost certainly has more experience than you, comes up with a statement like that there's two ways to take it.

    We could say "oh, he's full of crap - the boat is obviously unsafe because we think it is. He must be influenced by this factor, or that factor".

    We could say "gee, here is an enormously experienced sailor who has a different point of view. Maybe we should open our minds to what he is saying". I prefer to take this course.

    His information is not conclusive, of course. The fact that it has been backed up by many vastly experienced sailors is interesting. What such information surely should do is make us open our minds, at least, and not just say "that boat is a death trap" when it has been proven that the design can do 10 Sydney-Hobarts with no major problems.


    1 - there were rules changes after the Fastnet. The lessons were not ignored. I myself was racing offshore in '79. We typical offshore sailors of the time went to lectures from people who sailed through the storm, sailed with people who sailed through the storm, talked to guys who sat in with the committee that investigated it, etc. I have copies of the Fastnet '79 and Hobart '98 reports.

    2- Sure, we all know that fat boats have inversion problems as illustrated in Fastnet '79. I don't like fat boats, partly for this reason. However, as I pointed out in earlier posts, there were MORE deaths in the Fastnet on a Carter 33 (quite similar to an earlier version of a '70s S&S) than on ALL the lightweights put together. There were AS MANY deaths in the cruising-style Ohlson 35 Flashlight than on ALL the lightweights put together.

    Given that there were many MORE deaths from older or cruising-style boats than on lightweights and other new racers, any "lesson" seems blurred. Oh sure, fat lightweights can invert and that's not good - but the major races that have caused the most studies (Hobart '98, Fastnet '79) do NOT show a statistical trend for light or small boats to kill the most people.

    Okay, these are limited statistics are not perfect. However, to isolate one factor in one style of boat (capsize in fat lightweights) as is so often done, seems to be working from prejudice because it was a MINOR factor in the deaths. Yes, I am aware that the races highlighted a certain factor (capsize of fat lightweights) and that factor was worthy of investigation in '79 and '98. However, I submit that this factor has attracted far too much attention than it deserves, because it allows us to create numbers and be cast aspersions at a style of boat. There were many more deaths caused by other reasons that have been almost ignored, in comparison.



    "If you were to ask me to insure one of them I would charge as the premium the full cost of the boat and then some for profit after I have to pay for the disaster, and for that matter so would you."

    Well I assume you don't make a living as an actuary. Sisterships of the boat in the pic have been racing since 1986. They are still entering major races like the Sydney-Hobart. I think one has done 8 Hobarts as well as the Fastnet and Hawaii's Kenwood Cup. Not one has sunk. There has been no disaster. Statistically they are NOT unsafe boats. If you demanded a 100% premium assuming there'd be a disaster, you would have been 100% wrong over a dozen times.

    Interestingly, one similar boat just set the record for Sydney-Hobart races - 26 races (1 retirement with a broken rudder, I think) in 27 years. Another similar boat completed a bunch of Hobarts and then a singlehanded round the world race via the Southern Ocean, with no problems. As I mentioned, one of the few fractional lightweights from the '79 Fastnet has been a beloved cruising home around the Pacific Ocean and Tasman seas for over a decade.

    As you said yourself, we cannot take isolated examples, so your criticism of a boat based on a single photo cannot be regarded as having much weight when compared to the fact that such boats have a proven record of completing major ocean races.

    Is this a small statistical sample? Yes, it is fairly small. However, I can't find any larger statistical sample that shows that lightweights are unseaworthy.

    The boat in the pic is not my ideal boat. However the facts are that the design has a proven safety record. I have photos of S&S designs like yours in situations that look much worse, death rolling their guts out. Just looking at isolated pics or problems in extreme conditions tells us nothing apart from what our own prejudices are.


    PS

    I cannot see how you claim that saying you come from a superior gene pool is not bragging. The rest of that section is too political for me to reply to in a boat design forum.
     
  7. Guillermo
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    Guillermo Ingeniero Naval

    Capsize represents a small percentage of official reports of accidents at sea, being usually in the range of 1%, or less, at the known databases from national authorities or entities (like the RNLI and others). But one of the problems to interpret those databases is that some accidents due to stability related problems can remain hidden under other concepts.

    As an example, a well known database from the RNLI for a five years period previous to 1997 revealed that almost 5% of lifeboat launches were to leaked or swamped yachts, but the database did not distinguish those suffering from minor leaks below the waterline and those swamped in severe weather. Similarly, the data in the category 'adverse conditions' contain a variety of incidents or threats to the safety of the yacht concerned.

    Care must be taken in the interpretation of such statistics.

    On the other hand, a database of 115 sets of rigurous yacht and stability data were collected by the Working Group 22 of the ISO TC 188 (who collected them from a variety of sources), and used to develope the several STIX factors' formulae. About 30 sets of data involved yachts and vessels that had suffered a stability-oriented casualty of one kind or another. On top of that, the ORC was asked to carry out a systematic series of stability calculations, among their huge database of yachts, for a number of IMS ones with deck camber, systematically varied deck structures and cockpits, and sealed masts.

    During the course of collecting those data it became clear that serious knockdowns and capsizes happen more frequently than often supposed. The Group 22 was able to identify over 100 stability oriented casualties in the previous years to 1995 (They used the word 'recent'). They did'nt use the whole of those known casualties, limiting the study to the before mentioned group of 30 yachts, as it proved to be extremely difficult to obtain the required rigurous stability data from all of them.
     
  8. KevlarPirate
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    KevlarPirate Junior Member

    I am only posting to clear up mis-information, First of all, my first post was 658, page 44, I don’t remember ever stating about S&S
    except for my reference to Running Tide.

    I made the statement that the early seventies designed boats, I consider to be the peak of the curve for a balance of toughness, speed, and comfort and therefore make very capable seaworthy offshore boats.

    This is a general theory I hold which takes in many boats before they got light and fat. And I have sailed my share.

    I own 2 boats ,A 41 designed by C&C in 1968 and first sold in 1971. My other boat is Bruce king designed Ericson 46, I don’t know of these references you make to these other boats? Please post them. My boats are heavy by today’s standards with swept back fins and skeg mounted rudders.

    Both rudders have been upgraded with better and bigger design. This is the only area of improvement I considered needed, a simple one at that. They are tough, fast and comfortable and have nice sea manners in well developed sea.

    The reference you make to death rolls are because of huge sail area up , and small rudders. This is an issue of how these boats were sailed. The boats and many of their era have very high static curves over 130 deg. with over 7 to 1 pos. vs neg. areas.
    New fat butted boats have scary looking static curves, low moment of inertia. You will not find me on one of them in the open ocean. They can hold a lot of sail downwind because of their zero dead rise wide sterns but the payment for that is the static curve and bad dynamics in big ocean. When they wipe out it happens fast.
    Your problem may be what you consider a big sea. The boat I pictured was in a bathtub, how you can call that hairy is beyond me.
    Pulling both the rudder and keel out, obviously the rudder ventilated, no cruising boat would have EVER ended up with its rudder out of water with no control.
    My boats would have heeled and then come back up resumed sailing. Going upwind and wiping out like that is an example of everything wrong and no amount of excuses will cover it up . Totally laughable. And you must be drinking Koolaid.

    Also, I do not champion the Westsail 32. It is not my kind of boat. I referenced it as a boat that can lie ahull and because of it’s weight and motion, give comfort to the crew if they are incapacitated.

    In the storm I referenced the owners bag was found on deck washing up on the beach after obviously enduring hundreds and hundreds of beam on waves. This, then becomes statistically significant.

    Just as a product design is tested through many cycles whether it be temperature cycling or a shaker table. It is therefore NOT a single anecdote, but instead a valuable sampling. That is why I used it as an example.

    “I cannot see how you claim that saying you come from a superior gene pool is not bragging”

    nice try, never said I did, but I guess you still don’t get it.

    The USYRU and SNAME proved ,much to your obvious dislike that wide lightweight boats were suspect to capsize and long inversion times. The resultant Capsizing Screening Formula was later used by IMS to penalize designs which were going toward the wrong direction. Smart people know that.

    Go have fun in your boats, but if you try to promote these designs as safe offshore boats you will have others with physics backgrounds to deal with.
    That picture says a thousand words.
    Go read the books.
     
  9. RHough
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    RHough Retro Dude

    Plymouth to Las Palmas in August:
    1422 miles
    15 Days
    12.8 k Avg Wind Speed
    3.9 Avg Boat Speed
    4.4 feet Avg Wave Ht
    0.6 % Chance of Gales

    If we optimize the route to reduce the chance of gales further:
    1550 Miles
    16 Days
    12.2 Avg Wind Speed
    4.1 Avg Boat Speed
    4.3 feet Avg Wave ht
    0.4 % Chance of Gales

    The trip from Hamilton to Horta is:
    1998 Miles
    27 Days
    8.6 Avg Wind Speed
    3.2 Avg Boat Speed
    3.3 Avg Wave Ht
    0.0 % Chance of Gales

    From the Canarys to the UK in May:
    1767 Miles
    26 Days
    12.8 Avg Wind Speed
    2.9 Avg Boat Speed
    5.1 Avg Wave Ht
    0.7 % Chance of Gales

    I used 80% of the polar speed for my Catalina 30 to arrive at these numbers.

    I've posted screen shots of the routes that have the lowest probability of gales. As you know the Bay of Biscay can be a problem. :D

    The nice thing about the Canary<>UK trip is the lowest chance of gales also puts you close to the coast. In the real world, as you said, a cruiser would not make either trip in one go. If you chose to, the most gale free route puts you close to safe havens to wait for better weather if you catch that 1 day of 100 where there are gale conditions.

    The Bermuda > Azores Trip is a light air passage, the route shown has a 0 % chance of gales. This means that in August on that route no ship has ever reported a gale.

    I agree that we will have to wait until the right time of year to see how well the pilot chart information predicts "safe" routes. I'm up for the exercise when the time comes. :)
     

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  10. RHough
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    RHough Retro Dude

    I can't respond to incomplete scenarios.
    1. Halfway to Bermuda from where?
    2. What month of the year?
    3. Can you provide historical data (not scary anecdotes) that suggest that a storm develops in those waters at that time of year in 12 hours? Are you suggesting that there was NO indication 12 hours ago and now there is a storm? That is very hard to believe. :)

    Sorry, where did I imply that electronics are a substitute for piloting skills? If I'm in danger of grounding, I'm sailing in daylight and piloting. Don't even start to say that I have no choice. I consider it foolish to approach an unfamilar coast in darkness or bad weather. Piloting errors that put boats on reefs are just that, piloting errors. My 5mm hull won't be on the reef in the first place.

    You drive a Hum-Vee with 142 air bags don't you? :D Since you seem to think that smashing into things is normal. I certainly think that an unsinkable boat with crash bulkheads and water-tight compartments will do better after a collision than a '70's vintage boat that will sink and has no crash bulkheads. :)

    Seriously, containers and high speed in low visibility are a very real concern. I've given it some thought. Just because a boat is able to sail at 15-20 knots, there are times where that speed may not be prudent. Solo racers and the pros go flat out day and night, as a prudent cruiser I think there are times to slow it down a bit.

    Injured? You keep talking about getting injured ... how?

    "Cruisers are hacks." :) (***** at Robert Perry not me.) I work in a rig shop, many cruisers are cheap, ill equipped, ignore or postpone maintenance, and are an almost never ending source of half-baked ideas that don't have a snowballs chance in hell of working. You will find the cruisers that regularly encounter problems at your local sailor's exchange looking for cast-off used rigging and equipment that "looks better than what's on the boat". I'm sure that *you* don't fall into this category, but many "cruisers" do.

    System redundancy, seamanship skills, and planning go without saying.

    That's right. I ride motorcycles. No seat belt, no air-bag. My sense of self preservation is very highly honed. :) There are many cases of people getting as nearly bulletproof a boat as they can and then screwing it up. If they don't screw up they don't need a battleship. :) No one is talking about sailing in paper boats. You may prefer grossly overbuilt boats, you seem to sleep better behind 3/4" of solid GRP rather than 3/8". You boat weighs more than double what it needs to. The sails have to be bigger, and the loads higher ... is this how people get injured? :)

    Never assume that people haven't read technical information. In fact, one of the ongoing themes in this thread is the request for hard data that shows that modern light displacement boats are less safe due to design. Such data has not been forthcoming. You have added more opinion and sea stories, but little substance.
     
  11. Roly
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    Roly Senior Member

    Too right! Me for one.

    Randy,I have a couple of questions if you will.......forgive the mundaness of them.

    Sounds like a lot of work! For virtual time positioning what program will you use? How often will you download grib maps to convert to boat speed via your 80%
    of polar. Will your program do this automatically and does it optimise your course to your polars?
    Cheers
     
    Last edited: Mar 20, 2007
  12. charmc
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    charmc Senior Member

    "I've come to believe that we have passed two great turning points relating toYacht Design, in recent years, both of which have been under-recognized and I would like to put in my two cents to correct that omission.

    The first is the publication of this book, Seaworthiness, by C.A. Marchaj. Written partly in an attempt to sort out the 1979 Fastnet Race disaster, it is an effort to scientifically determine what constitutes a seaworthy yacht, one that has the maximum chance of surviving an offshore gale. And what do you suppose it says? It says, and in my opinion scientifically proves, that those old fuddy-duddies of decades past were right, and what you want for optimum offshore safety is deep ballast, long keels, attached rudders, V-shaped sections, non-planing hull shapes, and guess what else? A fair amount of weight in the rig. And the lighter you make the displacement, the more careful you have to be to keep the ballast deep, and the beam narrow, like the pre-IOR light displacement boats which first started the light-displacement revolution. I think every yacht designer and every race organizer and every magazine design editor should read this book--This is progress!

    In my opinion the other great event of our time is the advent of the IMS handicapping system. From the earliest days of yacht racing, designers have struggled to beat the various handicapping rules. In many cases the success of a design office has been completely based on their ability to beat whatever rule was in place at the time, and sometimes when a loophole they were exploiting was closed, those offices closed. Every rule was an effort toward objectivity, but every rule ended up encouraging a certain type of boat, often an unhealthy one. And to make matters worse, cruising boats have always imitated contemporary racing boats because yachtsmen are victims of style-consciousness like everybody else, and racing boats are assumed to be fast, even when in reality they were only designed to be fast for their rating. But with the IMS we have finally broken the objectivity barrier that has eluded us for the entire prior history of yachting. The rule seems to do an excellent job of rating boats of all types in a fair manner, and this seems to be born out by the race results, in which we see Concordia Yawls and Hinkleys and other boats more typical of traditional offshore yacht types, winning races and doing well. Still I don't think the full implications of the IMS are well understood. When I see a boat billed as "an IMS racer" in the magazines it usually looks like an old IOR racer, smoothed up and moderated perhaps, but still basically expensive, uncomfortable, difficult to sail, and not well suited to offshore storm conditions. To me, an IMS racer would be something quite different. She would be designed to keep sailing in the worst possible conditions with the least strain on her crew, partly because this is inherently desirable and partly because there are races to be won when the competition has retired or ceased to function effectively."
    Address by Daniel MacNaughton, brother of Tom, MacNaughton Associates

    It's possible that this might have been introduced earlier in this thread. If so I apologize for repeating it. But it seems that there is a breach coming up again and again. Those on one side say that lightweight racing type hulls with small modifications for comfort are good for offshore cruising. Those on the other side are, like Daniel MacNaughton, in favor of heavier boats, with larger or even full keels, capable of riding out an extreme storm with the crew disabled, or surviving a collision at sea with minor damage.

    As a sailor who would go cruising offshore with a few people I love, I have to weigh in with the second group. For the sake of argument, I think it is essential to eliminate the idiots who go underprepared, but to recognize that there is a major difference between a crack racing crew, which will typically include professionals who do little but race and work out, with their expenses paid for by sponsors, and a cruising crew, which will be much smaller, and composed of people who must live in the real world when they are not sailing. They will be skilled in seamanship, but probably not as physically fit as the pros. On a scale of 10, the average overall rating (seamanship and fitness) of an offshore racing crew will be 8.5 - 9.5. For a cruising crew, it may be 7.5-8.5. That does not make such a crew a bunch of unprepared fools. It means what I said, they are people who live in the real world when they are not cruising offshore. The lighweight racing type cruiser is seaworthy, as demonstrated by its ability to sail in heavy seas, often gaining speed by surfing, but it requires exceptional efforts by a large, highly experienced crew to achieve this performance safely. The heavier hull type described by MacNaughton, on the other hand, is seaworthy, as demonstrated by its ability to sail in heavy seas, somewhat slower but with an easier motion, and able to be sailed safely by a smaller crew. The requirement for more crew input is what makes the racer style boat less seaworthy -- as a cruiser. Randy, you seem to think Kevlar Pirate's mention of injury is not a serious argument. Be assured, it is. Particularly in a heavy storm, injury is an ever-present possibility, with the potential to cut the cruising crew's effectiveness by 30-50%. Final thought: I recognize that discussion tends to sound black and white . There are not 2 types of sailing hulls, heavy and light. There are many good designs which attempt to realize the best of the 2 extremes. My point is that a seaworthy cruiser design must factor in the possibility of being sailed shorthanded. Everyone will have a preference, and there is ample data to support arguments on both sides. I would lean toward a heavier boat with large keel and rudder. Such a design won't plane, but there are many of this type recognized as fast sailors.
     
  13. charmc
    Joined: Jan 2007
    Posts: 2,391
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    Location: FL, USA

    charmc Senior Member

    I look forward to the virtual sailing contest. Sounds like a fun way to test some ideas!
     
  14. CT 249
    Joined: Dec 2004
    Posts: 1,709
    Likes: 82, Points: 48, Legacy Rep: 467
    Location: Sydney Australia

    CT 249 Senior Member



    Like you, I don't agree with the most radical of light fat boats. Like you, I don't agree with RHough that you can always run away from bad weather. Where I live, the weather forecasts just aren't that accurate. In the 2000 Sydney-Hobart, even the pro Volvo Around the World race crews with all the professional forecasters working for them got the weather badly wrong.

    Nor do I feel that the old boats were dangerous. It's just that there is little evidence I can find to indicate that the virtues of lighter boats are outweighed by their problems (which have been studied and are recognised).

    It just seems that each type of boat has virtues and faults, and some of the most experienced owners recognise that. Some hold very strong opinions that favours one type of boat, but (to quote someone near and dear to you) I find many highly opinionated people are biased.
     

  15. Guillermo
    Joined: Mar 2005
    Posts: 3,644
    Likes: 188, Points: 63, Legacy Rep: 2247
    Location: Pontevedra, Spain

    Guillermo Ingeniero Naval

    Randy,
    Let's choose the Canary-UK trip, which is closer in time to check things. I think it would be better if you open a new thread for the follow up, instead of doing it here.
    Cheers.

    P.S.
    Interesting also to read Alain Maignan's round the world non-stop sailing log, aboard his Jeanneau Sun Rise "Schuss".
    http://alainmaignan.sportblog.fr/
     
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