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27-04-2015, 13:39
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#61
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Registered User
Join Date: Aug 2009
Location: Ontario, Canada
Boat: Challenger 32 1974
Posts: 523
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Re: The criteria of "blue"
I've a feeling that boats are more "blue water" than their crew.
Bill
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27-04-2015, 14:04
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#62
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Registered User
Join Date: Mar 2015
Location: New Zealand
Boat: Moana 33
Posts: 1,092
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Re: The criteria of "blue"
I too am searching and researching the market for a 'blue-water' boat so I'm taking this thread seriously but have not found much practical advice so far on this thread.
So, here are my thoughts: my focus is on safety, which for me requires (a) structural and systems integrity AND (b) an acceptable level of stability (Capsize Screening Factor < 2, or however you decide to measure it). Spade rudder and deep fin are less desirable but I won't entirely discount a boat as 'blue-water' because of these features; light displacement is out because lightweight means it is not built to withstand years of flexing and punishment.
"Integrity" can only be discovered through researching (i.e. reading up about) each yacht within our budget - build quality, design quality - followed by a most detailed survey of hull and systems, modifications and improvements. Some designs are obvious failures - windows (is that the correct term) too large or too weak to withstand knockdowns, flimsy rigging or stanchion attachments - but for most designs it will be a matter of crawling around inside, looking at bulkhead-to-hull/deck attachment, chainplates, seacocks and a near-endless list of checks, only some of which can be corrected.
Then it's a matter of costing out how much work is needed to remedy all those endless deficiencies, whether it's a new build or second-hand (it's unlikely that any new build production yacht will ever be completed to true blue-water standard). So the task is pretty much doing what any classification society surveyor would do - inspect the individual boat and the design/build specifications and compare them to a set of standards drawn up over the past hundred years or so of pleasure boat construction, except that we must draw up our own standards (unless we are lucky enough to afford a yacht built under Lloyds or DNV survey).
I hope this may be helpful and would appreciate any practical advice along these lines from others.
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27-04-2015, 14:57
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#63
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Registered User
Join Date: Jul 2010
Location: Fort Lauderdale, FL
Posts: 923
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Re: The criteria of "blue"
Quote:
Originally Posted by Cap Erict3
It is something I dealt with way back in the time I ran a BBS before the internet days.
The OP is fishing for reactions not info or real discussion.
------------------------------
Looking for another pretty place to work on the boat.
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Got it. We are on the same page.
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27-04-2015, 15:57
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#64
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Registered User
Join Date: Apr 2015
Posts: 504
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Re: The criteria of "blue"
Quote:
Originally Posted by NevisDog
I too am searching and researching the market for a 'blue-water' boat so I'm taking this thread seriously but have not found much practical advice so far on this thread.
So, here are my thoughts: my focus is on safety, which for me requires (a) structural and systems integrity AND (b) an acceptable level of stability (Capsize Screening Factor < 2, or however you decide to measure it). Spade rudder and deep fin are less desirable but I won't entirely discount a boat as 'blue-water' because of these features; light displacement is out because lightweight means it is not built to withstand years of flexing and punishment.
"Integrity" can only be discovered through researching (i.e. reading up about) each yacht within our budget - build quality, design quality - followed by a most detailed survey of hull and systems, modifications and improvements. Some designs are obvious failures - windows (is that the correct term) too large or too weak to withstand knockdowns, flimsy rigging or stanchion attachments - but for most designs it will be a matter of crawling around inside, looking at bulkhead-to-hull/deck attachment, chainplates, seacocks and a near-endless list of checks, only some of which can be corrected.
Then it's a matter of costing out how much work is needed to remedy all those endless deficiencies, whether it's a new build or second-hand (it's unlikely that any new build production yacht will ever be completed to true blue-water standard). So the task is pretty much doing what any classification society surveyor would do - inspect the individual boat and the design/build specifications and compare them to a set of standards drawn up over the past hundred years or so of pleasure boat construction, except that we must draw up our own standards (unless we are lucky enough to afford a yacht built under Lloyds or DNV survey).
I hope this may be helpful and would appreciate any practical advice along these lines from others.
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I can not give you any advice NevisDog as I have minimal experience but I am thankful you responded to the OP seriously and gave consideration and thought to this issue. I spent the earlier part of this evening reading the associated pdf on this link. https://www.gov.uk/maib-reports/caps...loss-of-1-life You may or may not be familiar with this tragedy but it was of interest to me because the subject matter concerns a sub 40 foot bene production boat which is supposedly the polar opposite of a blue water cruiser to many people on this forum.
It took some rough weather and was knocked down twice. The second knock it inverted however and stayed inverted for rather too long. The report concludes that the boat is not suitable for crossing an ocean in storm conditions. However, I think it is a good starting position for me at least of what should be expected and that is that the hull should come back round rather sharpish if an invert happens. In fact my #1 want for a blue water standard is a guaranteed return with out having to rely on another big sea to get the ball rolling. If this boat had turned back over quickly a life would have been saved. I'm guessing though that to have this ability the boat would have to give some of its initial stability away.
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27-04-2015, 16:46
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#65
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Registered User
Join Date: Mar 2015
Location: New Zealand
Boat: Moana 33
Posts: 1,092
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Re: The criteria of "blue"
The report on the Beneteau 39 tragedy is new to me but for such a yacht to capsize (twice) in force 8-9 conditions certainly confirms my second criteria - stability - as being one of the two deciding factors on what is 'blue-water' capable. I note the enquiry finding that a Beneteau Oceanis 39 is "not a suitable yacht to cross oceans" (or words to that effect). Thanks for bringing this report to our attention, Paul - I recommend everyone should read it.
There are several measures of stability criteria for ocean going yachts - not sure it matters which we choose but their importance is certainly brought home by the enquiry findings. Vanishing stability angle of 110 degrees may well be typical of modern fin keel, wide beam yachts designed (as most production yachts surely are) for the charter market.
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27-04-2015, 17:27
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#66
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Eternal Member
Join Date: Apr 2014
Posts: 848
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Re: The criteria of "blue"
Quote:
Originally Posted by Rhwins
Sail Calculator Pro gives stats on many boats. You can set up your own criteria but the "Capsize" ratio of 2.0 or lower indicates the boat is acceptable for ocean racing on that criteria. Doesn't say the thing won't get dis- masted in a full gale though.
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Please don't put too much stock in the Capsize Screening Formula... It is so basic as to be essentially worthless, for anything more than eliminating the most egregious offenders of stability from consideration...
For example, take 2 identical fin keeled boats... Unbolt the keel from one, and hoist it to the top of the mast...
According to the CSF, the resistance to capsize of both boats will remain the same...
:-)
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27-04-2015, 17:44
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#67
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Registered User
Join Date: Mar 2015
Location: New Zealand
Boat: Moana 33
Posts: 1,092
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Re: The criteria of "blue"
I wonder if perhaps the moderators of this site could clean up and delete those many comments that are rude, unhelpful, or both, please? The near worthlessness of CSF was a surprise to me - but the post is quite correct. That sort of info is incredibly helpful to anyone interested in this subject but finding such snippets among the trash is really hard.
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27-04-2015, 17:52
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#68
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Moderator
Join Date: Jan 2007
Location: Pacific NW, USA
Boat: Cape Dory 27
Posts: 8,577
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Re: The criteria of "blue"
Quote:
Originally Posted by NevisDog
I wonder if perhaps the moderators of this site could clean up and delete those many comments that are rude, unhelpful, or both, please?
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My pleasure.
Just a friendly reminder folks - stay on topic, avoid the barbs and jabs, they are unwanted and uncool. If you take issue with another poster please report the post but do NOT respond in kind. We expect collegial posting.
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27-04-2015, 18:08
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#69
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Registered User
Join Date: Sep 2012
Posts: 5,983
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Re: The criteria of "blue"
This subject has been beat to death in many past threads. If your answer to the holy grail is based on results then almost any boat with a good sailor can cross oceans even if its poorly built and has a less than required righting moment. So jump into an old Cal 25 or Catalina 27 and you are good to go because these boats have been sailed around the world or take out your check book and buy an Oyster/HR as it will get you there as well. Keep one thing in mind, in life you can't buy cheap/high quality/excellent service products but every year hundreds of cheaply built boats are safely crossing oceans and for the most part, except for the odd exception they get to where they are going.
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27-04-2015, 18:17
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#70
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Eternal Member
Join Date: Apr 2014
Posts: 848
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Re: The criteria of "blue"
Quote:
Originally Posted by Steady Hand
What is seen and what is not seen in a video.
...
Original Poster of the Video on Youtube ("Desh"):
...we had these conditions for 18 hours by the end of which one crew member had been thrown across the saloon injuring his back...
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Hmmm, thrown across the ballroom on an Oyster 46, eh?
Wow, there's a shocker, difficult to imagine how that could have happened...
:-)
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27-04-2015, 18:33
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#71
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Registered User
Join Date: Sep 2012
Posts: 5,983
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Re: The criteria of "blue"
Not saying this is the case but camera lenses and angles will often make a space look much larger than it really is.
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27-04-2015, 18:36
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#72
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Registered User
Join Date: Apr 2015
Posts: 504
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Re: The criteria of "blue"
Quote:
Originally Posted by robert sailor
This subject has been beat to death in many past threads. If your answer to the holy grail is based on results then almost any boat with a good sailor can cross oceans even if its poorly built and has a less than required righting moment. So jump into an old Cal 25 or Catalina 27 and you are good to go because these boats have been sailed around the world or take out your check book and buy an Oyster/HR as it will get you there as well. Keep one thing in mind, in life you can't buy cheap/high quality/excellent service products but every year hundreds of cheaply built boats are safely crossing oceans and for the most part, except for the odd exception they get to where they are going.
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This is all well and good but would you not agree that there should be a blue boat specification set down. If not then we are are just dealing in shades of grey or plotting points on venn diagrams for best compromise all the time. If you can afford to buy a custom designed boat then you obviously can set your own specification but if you are buying semi custom or an off the shelf "blue water" boat should we not be able expect some common standard of conformity that we can rely on. Surely we should have some some basic index that definitively quantifies what a blue water boat is that enables us to measure what is being sold to us. No?
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27-04-2015, 18:41
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#73
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Moderator
Join Date: Feb 2010
Location: La Ciudad de la Misión Didacus de Alcalá en Alta California, Virreinato de Nueva España
Boat: Cal 20
Posts: 20,490
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Re: The criteria of "blue"
Quote:
Originally Posted by Jon Eisberg
Please don't put too much stock in the Capsize Screening Formula... It is so basic as to be essentially worthless, for anything more than eliminating the most egregious offenders of stability from consideration...
For example, take 2 identical fin keeled boats... Unbolt the keel from one, and hoist it to the top of the mast...
According to the CSF, the resistance to capsize of both boats will remain the same...
:-)
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It's not as bad as righting moment graphs salesfolks like to trot out with Maximum Righting Moment, Area Under the Curve and Angle of Vanishing Stabiltiy all solemnly explained and discussed as if they were the be all and end all of capsize resistance.
In reality these values represent static stability attributes and capsize is a dynamic process. There is somewhat of a negative corrolation between righting moment and capsize resistance. As an example boat that has lost its mast has a higher peak righting moment, a larger AVS, more area under the curve AND it is more susceptible to capsize by a breaking wave. The same is true to a lesser extent for undamaged boats: Same boat but with a lighter mast is more susceptible.
This is without even trying to defeat the formula like raising the keel to the masthead, this is comparing boats in their normal sailing conditions.
__________________
Num Me Vexo?
For all of your celestial navigation questions: https://navlist.net/
A house is but a boat so poorly built and so firmly run aground no one would think to try and refloat it.
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27-04-2015, 18:43
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#74
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Registered User
Join Date: Jan 2012
Location: San Diego
Boat: Pearson 39-2 "Sea Story"
Posts: 1,109
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Re: The criteria of "blue"
Quote:
Originally Posted by paulanthony
This is all well and good but would you not agree that there should be a blue boat specification set down. If not then we are are just dealing in shades of grey or plotting points on venn diagrams for best compromise all the time. If you can afford to buy a custom designed boat then you obviously can set your own specification but if you are buying semi custom or an off the shelf "blue water" boat should we not be able expect some common standard of conformity that we can rely on. Surely we should have some some basic index that definitively quantifies what a blue water boat is that enables us to measure what is being sold to us. No?
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Who should set this standard? How will it keep up with changing technology? Will all who set out be required to have boats that meet this standard? What happens the first time someone sets out in a Certified Blue Water Boat and doesn't make it? Shall we have them pay back any rescue fees because it was obviously the sailor's fault, since the boat was CBWB? Or shall we sue whoever decided that it was a CBWB boat?
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27-04-2015, 18:48
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#75
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Registered User
Join Date: Apr 2015
Posts: 504
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Re: The criteria of "blue"
Quote:
Originally Posted by Jon Eisberg
Hmmm, thrown across the ballroom on an Oyster 46, eh?
Wow, there's a shocker, difficult to imagine how that could have happened...
:-)
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hahahahahahaha... so funny. )))) yeh. Life is hard for some...
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