Let´s be practical. Are we in the right way?

Discussion in 'Stability' started by Antonio Alcalá, Nov 6, 2007.

  1. Antonio Alcalá
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    Antonio Alcalá Ocean Yachtmaster

    jorghenderson ... Are you ready for answering me my question or maybe not?
     
  2. jorghenderson
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    jorghenderson -

    questions

    I am ready to tell you that i would rather not have responsibility over a yacht and its crew unless i have confidence in the boats ability. Most high volume low price boatbuilders make concessions to quality that affect their products ability at sea.

    The Beneteau was about 40ft and not very new.
     
  3. Willallison
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    Willallison Senior Member

    Vega - another quick word of caution to add to those already put forward by Mike.... assuming you are travelling at 8 knots, my rough estimate is that you'd have just 36 seconds to stop after your fwd-looking sonar suggested that you might be about to hit something.... Not a lot given that it'd probably take 1/2 that amount of time for ones brain to figure out which electronic aid was beeping and why....
     
  4. CT 249
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    CT 249 Senior Member

    Umm, what???????????????

    That is completely and utterly wrong and unfounded.

    There were four* "full keel" boats in the 1998 Sydney Hobart. HALF OF THEM SANK AFTER STRUCTURAL DAMAGE

    A full entry list (115 boats) is available at

    http://www.equipped.com/sydney-hobart/Vol 17 Exhibits/Exhibit 09.pdf

    The full-keel boats were;

    Canon Maris. Tasman Seabird.

    Winston Churchill. Old planked Coverdale 51. Knocked heavily by big sea. SANK. Three lives losts.

    Mintaanta. GRP double-ended Swanson 42. "Knocked down" according to her skipper, after retiring. Suffered major structural damage. SANK.

    Southerly, Peel 35, '50s, planked. Retired IIRC.


    Full keel boats provided less than 4% of the fleet, 40% of the sinkings, and 50% of the deaths. Even if we exclude the old Winston Churchill, they provided less than 3% of the fleet, yet scored 25% of the sinkings.


    Yes, dealing with stats in such small samples is dangerous, but you are wrong on all your counts. Full keel boats did NOT make up 10% of the fleet. They were NOT immune from knockdowns. They DID suffer structural damage.

    Even if we look at boats with long, faired-in fin keels typical of late '60s/early '70 racers, we see;

    Berrimella - recently knocked down and sent Mayday while returning from a Hobart - AFTER completing a doublehanded circumnavigation via the Southern Ocean.

    Breakaway - Swanson 36. No reported incident. Finished IIRC.

    Gundy Gray, steel Adams 40 cruiser. Laid flat, "mast in water" (see p 6,
    http://www.equipped.com/sydney-hobart/Vol 10 Docs/GREEN Robert Vivian.PDF). Lost gear.

    Kingurra, Professor Joubert (engineer, NA),. 1972 very heavy Joubert, cold moulded - knocked heavily. One crewman overboard. Boat could not get back to him. Saved by the freak chance of a helicopter being nearby.

    Margaret Rintoul II. 1968 heavy S&S, cold moulded. Highly experienced crew felt she could not stand by Sword of Orion due to the danger.

    Misty - 1968 (design) S&S 34. GRP. Finished well, I think.

    Morning Tide. 1968 (design) S&S 34. GRP. No reported incident.

    T42 Solandra, 1968 (design) S&S 34, GRP. Knocked down to or very close to 180. Lost mast. Crew injuries.

    Veto, NZ Cavalier 38. No info.

    Mark Twain. 1972 S&S 39, cold moulded. No reported incidents.

    Polaris, 1969 design Cole 43, GRP. Retired early. No reported incidents

    Solo Globe Challenger, 1969 design Cole 43, GRP. Rolled or knocked 180 degrees. Crew injuries, lost rig, rescued. LATER COMPLETED SINGLEHANDED CIRCUMNAVIGATION NON STOP VIA SOUTHERN OCEAN.

    Ruff 'n Tumble, 1969 design Cole 43, GRP. No reported incidents.

    In other words, four of the 13 long-fin boats were knocked down and suffered loss of gear, severe crew injuries and other problems.

    Significantly, two of the boats in the '98 race and a near sister of a boat that lost two crew in the '98 Race have since done singlehanded (Farr 40 IOR Paladin and SGChallenger) and doublehanded (Berrimella) circumnavigations via the Southern Ocean. None had major problems doing so. When boats that can sail shorthanded around Cape Horn without damage suffer severe damage doing the Hobart, it indicates that the race is a true test of seaworthiness. Damage to lightweight racers must be seen in this light.



    * I've forgotten whether the NZ Cav 39 has a full keel. It retired IIRC.


    SO.....

    I have to say that your claim that 10% of the fleet were full keel is wrong. The claim that none of them suffered structural damage is wrong. The claim that none were knocked down appears to be wrong.
     
  5. condor
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    condor Junior Member

    Production boat, further thoughts

    The dialogue on this thread about producton boats and certain size issues has been informative. I will suggest a further thought or observation. In some rspects it does not matter how one feels about the issue. The way the markplace for boats is evolving, soon there will only be production boats.

    This development is akin to the maturation of the automoibile industry. At one time cars were hugely expensive, largely hand made and the industry had hundreds of marques. In the period form 1915 to 1945, the vast majority of these companies went out of business or were acquired. Hence General Motors, etc.

    Boating is going through this same consolidation. The costs to design and market a modern boat are very high. The public is demanding a high level of "features" and attendant engineering. Small volume producers are simply going to go away.

    So you can't buy a Dusenberg anymore. Boating is going to go the same way.

    The boats will be "better" in many senses, value, safety, engineering, etc. But they will lose charm, romance, exclusivity and saltiness.

    This is not a boating comment, it is a business observation.

    Condor
     
  6. MikeJohns
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    MikeJohns Senior Member

     
  7. CT 249
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    CT 249 Senior Member

    Hang on, Mike. I've read the full testimony of the Mintanta skipper and two crew to the Coroner. The skipper specifically says that no water was coming over the bulkhead ahead of the engine compartment so "nothing was coming in from the rear". He says he believes the garboards failed.

    The witnesses say the skipper checked all skin fittings, even when he had to move an anchor. Why did the Taylor report decide that the skipper had 1- checked for water flowing forward over the aft bulkhead and not seen the supposed stuffing box leak; and 2 - checked all skin fittings but not the stuffing box? Why did the stuffing box choose then to fail? Why did the owner believe it was structural failure? Has the same level of proof of structural failure been required when assessing the loss of light boats?

    Your previous post says no long keelers suffered structural failure, your above post says a stuffing box was "just as likely" as structural failure. Therefore instead of "no" failures in full keelers we now have a 50% possibility of one, even if we assume that Mintanta's skipper is wrong about there being no water in the aft sections and that he did not check the stuffing box although he went to great lengths to check the other skin fittings. Where has your certainty gone in just one post?

    If you pulled the 10% figure from the Taylor article it indicates that the Taylor article is unreliable in at least some respects, because the 10% figure is not correct. After the four full-keeled boats, the 3 Cole 43s had the next closest thing to a "full keel" and one of them rolled or inverted. Ergo the "around 10% and no rolls or damage" claim is patently untrue which must cast doubt on the rest of the source.

    The vessels that were rolled or inverted include Naiad; B52; Loko (heavy Swan); Solandra (S&S 34, LPS of 130 with 4,901kg displacement on about 24' LWL) and Solo Globe Challenger (approx 33' LWL, about 9.8 tons, LPS of 139).

    That's not a disproportionate amount of light boats, and two inversions or rolls of heavy boats with LPSs 130+ indicate that inverting is not the preserve of lightweights. Both the heavy designs that inverted have done singlehanded circumnavigations via the Southern Ocean and neither is renowned for being dangerous or flighty.


    By the way, in reference to your earlier post "Much has been made of the Winston Churchill foundering in the Sydney to Hobart to supposedly illustrate that there is no advantage in heavy boats, but she was a racing boat and designed as such to rate well, not to be seaworthy . She also had a very low AVS."

    Winston Churchill was not an inshore Metre boat; nor was she designed to the RORC rule as she was not a new boat in 1945 and Illingworth had to show the CYC how to measure boats; ergo it is highly unlikely that she was designed in Australia to a rule that was not in use in Australia, and which was having little impact on the typical UK boat at the time.

    Winston was, I believe, a fast cruiser of her day.
     
  8. MikeJohns
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    MikeJohns Senior Member

    For a start I said "Here is a thought" I may well be wrong, ...no problem that's a human prerogative, by sensibly introducing the facts the truth unfolds.

    Taylor implies the truth was warped; like the inclusion on Miitinta as scratching at straws as she was well out of the theater and in safety when she sank nor did she suffer damage from a knockdown.
    As for the belief of the owner as to the source of the leak it is nigh impossible to tell where the water is coming from in a partially flooded vessel. Also to consider is that she was 22 yrs old with a long history.
    The point being that to include her loss as design specific is at best questionable. To imply that she was knocked down and sunk from structural damage in the same theater with Sword etc is not very tenable.

    Winston was not rolled but stove in above decks she was an old trad planked vessel that should not have been there at 46 yrs old. Whether or not Illingworth designed her to perform specifically for racing she was not designed for seaworthiness as she had a relatively low AVS.

    Another heavy boat "Kingurra" was knocked down and retired returning without assistance. She suffered some deck damage apparently but she was also quite an old vessel at 28 yrs . So the line up of heavy vessels that were counted as distressed does not draw much of a fair comparison although this was the evidence presented as proving that light and heavy faired alike.
     
  9. MikeJohns
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    MikeJohns Senior Member

    Not this material is the academic property of Kim Taylor. These graphs of normalized data are quite interesting ( bearing in mind what I said about Miintanta she should not really be counted)
     

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  10. CT 249
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    CT 249 Senior Member

    "by sensibly introducing the facts the truth unfolds."

    Yes, but none of the claims you made were facts. Your claim of the proportion of full keel boats was wrong. Your claim that full keel boats escaped structural damage is wrong. Crews said that their full keel boats were 'knocked down'.

    Why should Mintanta should not be counted as a casualty? She was in heavy conditions when she sank. And since when was sinking when out of the "theatre of damage" (ie in calmer waters perhaps) an excuse for sinking???? Was the same excuse offered to lightweights that have been lost?

    The true straw that is being clutched is trying to exclude a boat like Mintanta (which was entered in the race; competed in the race; was in the region of other boats in the race) from the toll of casualties, apparently on mere supposition that she had a stern gland problem.

    The owner gave evidence that the water was NOT coming from aft of the engine bulkhead. You and Taylor, who were not there, assume that the owner made a mistake and checked all the other skin fittings (confirmed to the police by three witnesses) but happened to miss the stern gland. Where is your proof or indication of this allegation?

    Surely any objective person would take the evidence of the people who were there, and who checked 'every' skin fitting, and who did not see the water coming over the aft bulkhead, and who have given their opinion of the loss, over those who were not there.

    Your point of age is extremely debatable. You use the age of Kingurra and WC as a reason for their problems - yet there were few newer heavy boats to compare them with. The newest heavy boat, the Swan 48 Loki, also rolled. Maybe a new heavy boat in Kingurra's position would also have been damaged. And Kingurra is an extremely tough boat.

    Saying Kingurra returned without assistance is really pushing the limits, as she had left a crewman in the water astern and had several injured crew. The man in the water was saved only because a helicopter was nearby - Kingurra could not get back to him.

    "Winston was not rolled but stove in above decks"....yes the bulwarks were smashed. Why did she sink? Garboard damage perhaps, according to evidence. Again, there is an attempt to exclude the heavy boat from the count of the losses because of her individual details compared to some ideal that is not in the event - yet have you excluded light boats that encounter trouble because of THEIR individual faults, or have you condemned lightweights as a species? I suspect the latter.

    The other point is that once again, the fast strong heavyweight ideal you espouse is not to be seen in this race - because few or none of these ideals exist or race. We cannot logically compare real boats with the phantom ideals that are thrown up. If these phantom ideals met real races and real waves, they may find problems that are not apparent in the world apart from real races. Please, where are these boats that are heavy but comparable in speed to lightweights of which you have written?

    "Whether or not Illingworth designed her to perform specifically for racing she was not designed for seaworthiness as she had a relatively low AVS."

    What? Illingworth designed Winston????? Really? Why then is Coverdale always designated as the designer? Why is Illingworth, who only arrived in Australia a couple of years later, not given as her designer? Why is she so different from his other designs?

    Since you don't even know who designed WC, how do know you whether or not she was "designed for seaworthiness"???????
     
  11. Paul B

    Paul B Previous Member

    You will never provide enough facts to sway the opinion of true believers.

    You have to remember some people make their livings by using fear to drive sales of their product. I hear you can even get whole countries to approve the invasion of another country by using the same tactic. Back when I was in the boating business I often heard people, sometimes my own clients, telling neophytes how unsafe it would be to venture outside of the marina in anything less than a Mason 43.

    I also once had a girlfriend whose father would not allow her to ride in my "unsafe" sports car. He insisted we only use her truck. When I presented the data to him showing the "safe, heavy" vehicle was actually less safe (rollover problems) than my "unsafe, light" vehicle he became angry. Of course he also still insisted his daughter could only ride in her "safer" vehicle.

    I have to assume the people who are so afraid of light boats must also only drive things like DeSotos and Cadillacs from the 1950s. Driving is a much more dangerous activity than sailing, and those older, heavier vehicles must be safer, right?

    As for various charts and graphs people present, I have a book in my office called How To Lie With Statistics. Basically, it shows how you can "prove" any side of an argument using the same data set. In science we call it manipulating the data.
     
  12. CT 249
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    CT 249 Senior Member

    True, Paul.

    Those charts are interesting. They clearly show the very high LPS of Solo Globe Challenger, which went very close to upside-down.

    They also exclude the S&S 34 Solandra, which had a very high LPS yet inverted or was very close to it. Why is a heavyweight that may have inverted left out of the reckoning?

    The other thing the chart does not show is the likelihood of each type getting into trouble IN RELATIONSHIP TO THEIR PROPORTION OF THE FLEET.

    Yes, more lightweight racing boats got into trouble - but they made up the majority of the fleet. The heavies may have actually suffered worse IN PROPORTION TO THEIR NUMBERS.
     
  13. MikeJohns
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    MikeJohns Senior Member

    The idea of these exchanges is to state corrections simply and quietly without all the great excitement and I will either stand corrected or I will question in turn, and we can all learn.

    Looking at that one liner you have lambasted so thoroughly, I posted:

    Here's a thought.... Around 10% of the 98 Sydney to Hobart were full keel boats none of them suffered hull structural damage, but then none of them were knocked down or rolled.

    You are right this statement is wrong .

    In fact from memory I confused things sorry.
    Mr Taylor he said in his article

    Those interested in the Long/Short keel debate may note that none of the 11 per cent of the fleet with long keels was rolled

    I don’t know what he counts as a ‘long keel’ as opposed to a ‘short keel’ but it is not a full keel as I erroneously stated.
    It also states that the committee’s findings ;
    “structural damage to yachts other than those rolled was relatively minor” (excepting Winston).


    Yet age accounts for significant structural weakness due to fatigue, prior repair, material degradation and undetected damage/decay. It is always sensible to make a distinction when looking at failures between design and maintenance related issues.

    The interest is in the vessel hull-form and how it fared. A failure to tether a person to a vessel doesn’t question a hull-form. Kingurra was heavy, she didn’t roll, even after her experience she returned under her own ‘steam’ after her MOB was collected by helicopter.

    Didn’t she have a stove in coach house roof too which was attributed as the cause of her sinking?



    It is informative to look at the extremes, at what point do vessels become unsafe in heavy weather? You would have no trouble admitting that BP Niad should not have proceeded into the weather forecasted.

    I thought this was about real comparisons of real boats. The ‘phantom ideals’ thrown up include such ideas as strength weight trade-offs material properties, low stability and it’s attendant vices.

    I have said before it is perfectly possible (as is evident) to make light strong and seaworthy boats. Providing you can accept the lower comfort factor. The issues are strength and quantity of materials, hull form, damping and AVS and design life-span.


    Mintanta is interesting. For the sake of the case lets say that she did develop a crack in her lower hull from continual pounding . Given her age, anyone here who surveys GRP boats will know just what variables and history can be present with respect to a compromised laminate. Would this then be sufficient to warrant the condemnation of the hullform? Is it possible that her sinking could have been avoided had she a bilge alarm fitted? It would also be a fault easily remedied in another vessel of the same type, unlike the major design flaws apparent in some other vessels.

    Likewise Winston C is more about materials age and construction than about hullform.

    The few heavy boats that come in for such lambasting have factors other than their hullform which can account for their problems.

    No , my mistake.
     
  14. MikeJohns
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    MikeJohns Senior Member

    Actually the point Taylor was making was that Dovells analysis of the Light V's heavy vessels was just as you say, some creative accounting. In Dovell's case to try and shed criticism of some more modern lightweight hullforms by obfuscating the issue . You dont have to be very creative to see which vessels rolled.

    It would also be useful to separate out preventable failures ie could we return the same vessel to the theatre improved to survive and what would we need to do to make it reliable.
     

  15. CT 249
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    CT 249 Senior Member

    Writing this while waiting for the kids to get ready to sail......

    “Those interested in the Long/Short keel debate may note that none of the 11 per cent of the fleet with long keels was rolled”

    115 starters. 11% of that is 12.65 boats.

    There were four "full keel" boats; Winston Churchill, Southerly, Maria and Mintanta.

    The next longest keels would have been the Cole 43s; Ruff 'n Tumble, Solo Globe Challenger, and Polaris (which retired early). Solo Globe Challenger was estimated to have rolled to 150; had several badly injured crew and was dismasted. Her owner felt for some time afterwards that the boat was gone.

    The next longest keels would have been the S&S 34s; Misty (no damage); Morning Tide (apparently no damage), Boomaroo (unknown) and T 42 Solandra. She had a "major major knock down and roll" in the words of her very experienced skipper, although he admitted that it was very hard to tell the angle. Solandra was possibly very close to 180 degrees in the words of a crewman who said the angle was "hard to determine". Boat dismasted.

    So the testimony given to police was that the boat rolled or was very close to it. Did Taylor raise Solandra? Perhaps given his apparent claims that Dovell cooked the books, Taylor should have noted that the heavy Solandra's skipper thought she may have rolled or inverted 180 and therefore arguably is also in the "rolled" category. She is certainly in the "heavy knockdown" category yet for some reason she is not in Taylor's charts. Why not?

    Secondly, what does the roll/non roll status of the heavies prove? According to Taylor's charts, six boats rolled - 5% of the fleet. Therefore statistically, there was only a 6% chance of any heavyweight yacht of the 12 rolling. Arguably we are dealing with such a small sample and with such low chances that it is wrong to draw strong conclusions, especially when the skipper of one heavy boat believes she may in fact have rolled.

    Interestingly, if Solandra did invert (as Eski and his crew thinks she may have done) then the heavies would look statistically worse than the lightweights!

    The point about age and stern glands being brought up is that it seems that such excuses are regularly raised when a heavy boat gets into trouble, yet similar causes are rarely or never allowed as excuses when a light boat gets into trouble.

    "The few heavy boats that come in for such lambasting have factors other than their hullform which can account for their problems."

    Arguably the reasons that "only a few" heavy boats cop a lambasting is because there are "only a few" heavy boats competing. They are much less likely to have problems because they are much less common. The fact that lightweights often cop more damage is arguably partly because there are more lightweights racing, yet this is often ignored.

    Yes, heavy boats can suffer problems because of factors other than their hull form - yet the same holds true for lightweights and yet they as a whole are often lambasted as a whole, as if the defect in individual boats applied to all of the concept. There has been shock and horror expressed about the damage to Stand Aside and Midnight Express, but was that just a construction problem? Arguably it was, yet their loss is often just used as ammunition against the lightweight concept.

    PS BP Naiad did not get a forecast of the weather she met early enough (testimony of Walker to coroner).
     
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