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

Yet Dovell himself (as a lightweight racing boat designer) has stated on several occasions now including an address to a working party on this very subject (ANA), that the design strength of many of the lightweight racing boats that participate in the S-H is apparently insufficient because the ABS rules underestimate the loads a vessel experiences when knocked down. This is compounded by designers chasing lightweight construction applying a low factor of safety to an apparently inadequate load assumption.

Where does that required extra strength come from? Either more material (weight) or more expensive materials, (very carefully and expertly applied in the case of high tech composites).

 

It is not displacement that determines speed, but sail area to diplacement. The original Colin Archer 32 footer caried over 1,000 ft of working sail. Modern versions carry the same sail area as a boat the same length but half the weight.
The popularity of steel boats has nothing to do with sailing , but everything to do with the number of Whales , floating containers ,ships, and other debris out there ,as well as the odds of surviving a bad grounding, and the elimination of deck leaks, etc.
The difference in passage times between so called light and heavy boats is minimal once you put all your belongings aboard. If you can't afford to take an extra day or two on a passage , take a plane .
Check the suvivability on this site under "Steel boats" That kind of peace of mind is worth far more than an extra knot on a passage, especialy if you have family aboard.
TheBbritish Maritime safety board said that a Beneteau is totaslly unsuitable for any offshore work in rough conditions.
They lose all stability around 127 degrees . Older designs often have positive stability to 170 degrees or more.Built at a time when materials and labour were cheap, they are far more strongly built than any modern builder could afford to build. And they leave enough money in the kitty to enable you to use them for what boats are for, freedom.
Brent

 

Mike, surely we can assume that Andy's boats since '98 have been designed with that knowledge in mind - yet they are not all that much heavier or more expensive, if at all, than the earlier boats. Therefore doesn't it seem quite possible that the extra weight required to make decks stronger does not greatly impact overall displacement? How much extra weight arer we talking about???

Brent; can you please provide us with some objective proof of the claim that SA/D alone determines speed? It's not something I've ever seen or heard of in any design texts, which also mention RM, DLR, WSA etc.

As far as I can make out, a Colin Archer 32 has a superior SA/D to a typical high-end '90s raceboat (ie Mumm 36, ID48 or a Farr 31); can you please provide us with information on a Colin Archer beating a boat of anything like that description?

I can't find much information on Archers racing; the few that did in Australia were very unsuccessful, and even in the '30s Lee Loomis' book "Ocean Racing" shows that they were regarded as uncompetitive against yachts of the Dorade/Malabar type. The only one I can find that has raced against modern boats recently was the slowest in the fleet (even up against much smaller and quite old yachts like the Contessa 32) but then again she only seems to have finished that race (North Sea to Stavanger) once; the other year she entered she was one of only two retirements, after losing part of her bowsprit and topmast.

 

"It is not displacement that determines speed, but sail area to diplacement"

I don´t agree with you, displacement is directly relationed to speed and indirectly relationed with motion comfort


.
"The difference in passage times between so called light and heavy boats is minimal once you put all your belongings aboard. If you can't afford to take an extra day or two on a passage , take a plane "


I donn´t agree with you again. Take a look at entry list of ARC 1990-2007 and you will see a huge number of "Beneteau", some of these even won ( 461,473,44.7 40.7,36.7). Could you explain me?. Speed is important, very important to escape of a low pressure system, and speed is important for less time on board in a ocean going passage. But, i don´t want speed without safety, i'd rather prefer both.

"TheBbritish Maritime safety board said that a Beneteau is totaslly unsuitable for any offshore work in rough conditions"

Please, tell me the url, and the page,where i can find this content and , please find the RORC web and jugde by yourself. Hundreds of Beneteau have crossed the Atlantic and the Pacific and never had problems. Are you kidding? You are telling me the 43 STIX of Oceanis 393, or the 51.5 of the 473, or the 44 of the First 44.7 or the 34 of the First 36.7 are not enough for crossing the Atlantic? Damn it! Then what is right and what is wrong? I could support opinions like nordic designs are more comfortable, better seaworthiness but never as suspicious opinions about french designs. Hugo Boss is sailing in a Finot design, remember

Best winds

 

and the shape of hull and the stability to carry that sail up.

Take a look at this boat test, by a conservative bluewater magazine:

"A few miles up the bay, we fell off the wind to hoist the huge asymmetrical chute and dumped the water ballast. It was like someone had stomped down on the accelerator. The boat took off instantly and the GPS showed the speed climbing to nine and then 10 knots—in 12 knots of breeze—as that pleasant hum raised a few cycles in pitch.

We were not even testing the boat, however. In 20 knots of breeze, the boat will broad reach at 15 knots or more; in 25 knots, you will see sustained speeds near 20 knots.
....

The cruising version is less Spartan and has a built-in galley to port, a standard chart table to starboard and a pleasant dinette arrangement…and cabin doors. Plus, it comes with an enclosed head. Heavier than the racing sistership, the cruising version probably will not sail boatfor-boat with the racers in highly competitive Class 40 events. It will, however, blow the doors off just about every other 40foot monohull on the planet.

Class 40s are not for the faint of heart. They are for sailors who lust after raw speed in boats that can be singlehanded or doublehanded across oceans or, for that matter, around the world. We can only hope that Class 40s catch on in the U.S. with the same fever that has swept Europe.


© 2007 Blue Water Sailing LLC. "

http://www.bwsailing.com/articles/2007/nov/akilaria-class-40/

 

safety

Looking at this thread and others it seems to me that you are trying to prove lightweight boats are suitable for crossing oceans. You do this by presenting Stix values and examples of yachts that have previously succeeded.

You also state that you are looking for a cruiser, not a raceboat. Anyone going to sea is taking an incalculable risk. Your crew will consist of family and/or friends not a professional racecrew willing to take some more risk in their business.

Sure, Hugo Boss is capable of crossing an ocean but if someone climbs the Mount Everest in his underwear without oxygen i will not make it my next holiday activity.

Making a passage in a carefully constructed lightweight boat will be more dangerous than making the same crossing in a well designed and build steel one.

For your viewing pleasure:
(warning: Do not try this in a Bene... Bata... Jean.... etc.)

http://www.youtube.com/watch?v=pp45fL0u0QU

Pushing a boat like this is much more comfortable when you know it was build from steel.

Bad weather is not always avoidable.

 

Hello Seaspark, I´ve got a Beneteau 473 and i love her, but not for the stix (52 calculated by Guillermo). We could say she has demonstrated me her absolute sailing potential. The 473 was built beeing forms of Open 60 and therefore is a fast boat. I have been in 50-65 knots going to Canary Islands sleeping inside with the automatic pilot. None problem : I usual sailing alone " solo" so i perfectly know the risk and my personal risk. I never felt that safety feeling under a storm. Yes i love her. She´s a cruiser-race. I like to eat miles, many miles per day. But if you question is if i´d change the 473, my response would be: Yes. Yes if i were rich. This is not my personal case. While i was in this situation i´ll not do a bad movement( i mean buy another boat).

But by the other hand i really fancy thinking a storm day in a Hallberg-Rassy 53, cooking, resting and reading in my cabin and outside 50 kts of wind. Less roll acceleration, more motion comfort good sail trimming. Do you like think about it? So am i

Is it bad dream ?

Best winds

 

I am not trying to prove anything, It is obvious that some light boats are not only suitable for crossing oceans, but designed for it. The Akilaria is one of them.

Probably, even if a boat like the Akilaria is unsinkable and compensates its lack of weight with a huge GZ. In the end the energy needed to capsize this one will be close to the one needed to capsize a typical 37ft steel boat with 9T.

I leave to each sailor the type of boat. It is a personal thing and personal tastes are wide in this area.

But my last post was about speed. That was what Brent Swain was talking about.

 

Vega, Antonio

Sorry Vega, my response was intended for Antonio (and everybody else ofcourse) we sort of cross posted.

Antonio,

The watch on this boat fell asleep, look at his face, despite the low resolution, his mustache, hand holding phone and the railing wire you can still see from his face he is content with his choice for a steel boat.

http://www.boatdesign.net/forums/showthread.php?t=20860

I have been thinking a lot about the design of a composite boat with enough foam in its structure to keep it afloat under most circumstances.

Look at one of my more drastic ideas:

http://www.boatdesign.net/forums/showthread.php?t=11074

 

Dovell was referring particularly to the lightweight boats which were damaged in the 98 S-H. They were damaged in his opinion due to clearly inadequate design strength. This I think is of particular interest since he clearly blames the boat design rather than the ‘awesome and unpredictable nature of the sea’.

ABS is accepted as the minimum structural standard to which offshore racing yachts should be designed and built. However some designers are claiming that their designs (that are clearly deficient), comply with ABS on the basis that it is a ‘guide’. They say they ‘consider’ their designs to be safe from their own assesment. This has recently been highlighted in Ken McAlpine's report ( NA commissioned by Yachting Australia ).

Recently both Andrew Dovell and Don Jones as prominent racing yacht designers have stated that some current designers are sacrificing strength and fatigue resistance for reduced overall displacement and reduced resistance.
This critique is not unique to these designers, it has been a common observation in the marine engineering field, and there is evidence that fatigue is so poorly understood by many ‘yacht designers’ that their engineering knowledge is clearly insufficient. Many appear to be working on minimal factors of safety over static loads. This is inadequate for ocean engineering but very attractive to performance oriented lightweight design.

Don Jones (I think designer of Skander, IchiBan, Quetzalcoatl ) has also been vocal recently in condemning keel designs on many modern racing boats saying they are a dangerous and will fail . Dovell as I said above now thinks that ABS is apparently inadequate for composites at the minimum allowable factor of safety for some scantlings.

These concerns are directed at the lightweight-high performance boats, they are about the boat being broken by the sea itself under imposed loads particularly but not exclusively in heavy weather. Adequate factors of safety on scantlings gives ultimate strength for the unexpected loads from rolls and knockdowns .
When it comes to design ( all being equal) the stronger vessels will be disadvantaged by the vessels who’s designers have sacrificed strength for a small increase in speed or a decrease in resistance (e.g. lower profile keel struts) . The racing skipper always wants a boat that is potentially a few minutes earlier to the finish line than a competitors.
I’m not even going near durability here when it comes to collision energy dissipation. Nor such issues as affect cruising boats suitability.

As for Dovell's current design policies I suspect that both he and other racing yacht designers are stuck with a very real dilemma, and that they see the solution in stricter regulation of scantlings to even the playing field. Mr Jones is clearly peeved, having even made press statements recently.



To re-visit this statement;
"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 ….. "

Dovell himself refers directly to the "Winston Churchill" as being a racing design.
So I think it fair to say that it was a traditionally built (planked) 50 year old racing boat with a low AVS, of questionable structural condition. It is then a creative argument to claim that this is can be usefully indicative. Let alone the lynch pin in an argument designed to take the heat of the lightweights. (IMHO)

 

Mike;

What I was trying to say is that we've seen no evidence that a lightweight design, modified with sufficient extra strength to satisfy the stresses identified in the '98 S-H and by Dovell and Jones et al, will become so much heavier as to become a heavyweight.

If, for example, we take a 5560kg 40 footer and add another 500kg in structure to it, will it be strong enough to satisfy Dovell et al and will it still be a lightweight?

It's just that you seem to be saying that no lightweight can be strong enough to cure the problems Dovell and Jones identify, yet we have not been provided with any information to confirm this. My guess is that you can be as strong as they want and still be a lightwieght, so there's no reason to get rid of lightweights. Sure, for god's sake make them stronger with better keels, but that won't necessarily turn them into heavyweights.

I haven't found my old materials re Winston Churchill; I'm glad to take Andy's word as 100% final in all respects if you are. In this case I believe that Andy may not be right, but I am not sure and my historical materials (which may or may not prove the point) are 120 km away.

I have not used WC as linch pin in an argument, apart from the fact that I have pointed out that lightweights are treated (by some) as if the failure of one or two boats shows that they are dangerous as a breed, yet when a heavyweight fails some people find some reason why it has to be treated as a special case. I still feel that this is being done.

Koomooloo's loss, and Mintanta's loss, and the problems with the heavyweights in the NZ-Tonga rally, are often picked apart as being specific to the boat or crew and not a problem with heavies in general. In contrast, the loss of Sword of Orion, Stand Aside or Naiad as seen as proof of the dangerous nature of ALL lightweights.

For example, the accounts of those who were there appear to sometimes be ignored to "prove" than Mintanta sank because of a stern gland failure (despite the fact that NO water was coming from the relevant bulkhead over which it must have been flowing) rather than a structural failure. In this case even the eye-witness evidence to an inquest is being attacked and a theory with no proof presented is being put up.

But the same doubt re eye witness testimony is not being applied to lightweights. It's been said Mintanta only sank because she had a bad pump - well, Sword of Orion and NAdia didn't sink at all and if they didn't have crew with 1 had heart and 2 with harness/rigging obstruction problems, no-one would have died. Yet the deaths aboard the conservative, heavy, Ohlson 35 Flashlight in the 1979 Fastnet are ignored, like the four deaths on the heavy-ish Ariadne.

Three boats are knocked down. On two of them, sailors and their harnesses are entangled or struck by rigging and die - that is seen as a proof that lightweights are dangerous. On the other, two are thrown overboard, their harnesses fail and they die - yet that is not seen as proof that heavies are imperfect. Yes, I don't like the inversion time of Naiad, but if Skeggs had not had a harness problem - like the two who died off Flashlight - he would very likely have been alive today.

There is also a tendency to ignore the fact that lightweights make up the vast majority of ocean racing fleets and therefore are likely to form the vast majority of casualties. And we keep hearing things like heavyweights are fast, yet never see any evidence.

 

Not the issue is it?

Yes but all being equal it will be slower, there is also a design spiral in adding this.

This isn’t a conspiracy to rid the world of lightweights and you will forgive me for quoting myself earlier in this thread;

but accept the compromises.

Surely it’s about inadequate unsafe boats (in heavy weather) driven to the extreme by the desire for performance. The point is that this is occurring. People within the racing camp including both designers and administrators are apparently becoming concerned when often before, concerns were stonewalled or quietly ignored.

A worry is also the trend to mimic racing boats for performance cruisers without consideration for their lack of durability or their suitability which is of interest to this thread .

But it sounds compelling and it is dished up enough (even by you in the past) to be well on its way to urban mythology “Heavy and light fared alike….The greatest loss of life…One of the heaviest boats….”

Why did it fail. What could we do to make it safer next time. Is it a hullform seaworthiness issue? Is it a materials strength and application issue ?
Do they match the profiles for unsuitable craft given their stability or hullform or scantlings, and were more predictably likely to meet with disaster.
These are the important questions from a scientific perspective.

Why couldn’t the water have been flowing underneath that bulkhead? Partial bulkhead separation is common enough in GRP vessels subject to slamming and wracking.

There was apparently no water ingress while the vessel was under sail which is when you would expect the garboard to be under greatest strain but only after motoring for some time.

I think it is important to go over the salient points again :

The vessel was no longer In the race it had pulled out and was going home under motor, on going below someone found water in the boat, they turned the bilge pumps on, the owner tried to locate the source of the leak but could find nothing. The vessels inbuilt bilge pump stemmed the water level. Worried about the leak they received assistance and while under tow by a vessel out of Eden the pump intake clogged. Then they let the vessel sink; no buckets, no manual pump, no auxiliary pump from the rescue vessel. They were too tired perhaps? It appears to me that the boat was certainly well insured, but that may be an unfair comment.

We know nothing about the source of the leak except that the skipper says he couldn’t find it, this is no surprise. Identifying the source of a slow leak in a partially flooded vessel requires it to be bailed.

Now this was an older boat, what 25 years old ? Do we have any history of prior damage and repair ? Was it compromised by it’s build quality? It certainly is likely to have had some osmotic problems it may have had some severe delamination.

Does this deserve to be included in a conclusive analysis as a hullform ‘sunk’ in the 98 S-H as Dovell claimed in his original report, implying that it was sunk in the storm ?

Without rescue.

No ones ignoring these, we haven’t even been mentioning the 79 Fastnet.

All vessels can be poorly designed for seaworthiness, it’s neither useful nor informative to polarize the discussion, every vessel should be analyzed on it’s own merit and mode of failure.

We have discussed the very real and dangerous relationship between low AVS and long inversion times before now, it has killed people before, expect it in the future.

Fast is a misused term, to the racer particularly on the club circuit it is not synonymous with maximum hull speed. In contrast there is a tendency amongst many in the racing fraternity to view cruising boats with disdain. yet if the vessel is out of semi planning mode you are a displacement craft and VP is based on the same parameters as any other design. These are the immutable rules of the game unfortunately. Then it’s down to total resistance and total drive. You are unlikely to see the sail area on a cruising boat to give that racing performance, and who would design a heavy racing boat these days (since displacement contributes to resistance)?

Forensic engineering is a science that should be well applied to data before drawing conclusions. Dovell’s analysis for the CYC made no effort to identify the particular shortcomings of the various craft. His report used by the CYC and the coroner has even been contradicted to some extent by his own subsequent ANA working party contributions.

Taylor’s charts that I posted before are indicative enough to draw some simple conclusions about the suitability of hull-forms with regard to overall length, displacement, and stability. At least indicative enough for some basic recommendations. The inclusion or exclusion of a vessel is not going to significantly alter that.

Naval architecture predicts that lightweight beamy lower AVS vessels will be more at risk.

 

Those are the points....!

Cheers!

 

There does seem to be an issue in that some people appear to attack ALL lightweights; the idea that all lightweights are unacceptable is what I am attempting to disprove.

Like you, Mike, I believe that current design should accept a small speed loss in exchange for improved strength and seaworthiness. This has not been ignored in the past, it has actually been a recurrent feature (and similar arguments were used against "dangerous lightweights" like S&S boats in the '60s).

Re Mintanta;
"Why couldn’t the water have been flowing underneath that bulkhead? Partial bulkhead separation is common enough in GRP vessels subject to slamming and wracking."

I don't know the boat (although I did a tough 1080 nm race against her, on her sistership) so I don't know whether it was possible; I suggest that neither of us probably know whether the owner checked in some way. Have you applied the same level of doubt and scrutiny to the accounts that have been used to discredit lightweights?

It seems that there is a willingness to accept eyewitness accounts of the cause and extent of structural failure in lightweights, and a strong tendency to doubt eyewitness accounts of the cause and structural failure in the case of Mintanta.

There was apparently no water ingress while the vessel was under sail which is when you would expect the garboard to be under greatest strain but only after motoring for some time.

Emerson, the owner/skipper, says that the water rose over the floorboards about an hour after he started motoring (in 80 knots of wind and 10m seas). Given the depth (IIRC) of a Swano 42 bilge, she had a lot of water by then. There seems to be no proof that the damage happened while motoring.

Certainly the owner does NOT believe the damage happened while motoring and he does NOT believe it was the stern gland - once again the evidence of those who knew the boat and who were there is being ignored to try to exclude Mintanta from the list of losses.

I think it is important to go over the salient points again :

"The vessel was no longer In the race it had pulled out"

If we exclude Mintanta from the stats because it had pulled out, we must also exclude Sword of Orion, B52 and other yachts which had also pulled out. Your call.

Here we have one more example of the tendency to dismiss the loss of a heavyweight for a reason (she had retired) that is not used when discussing problems with lightweights.

Then they let the vessel sink; no buckets, no manual pump, no auxiliary pump from the rescue vessel. They were too tired perhaps? It appears to me that the boat was certainly well insured, but that may be an unfair comment.

This is incorrect. The crew bailed for hours. See the testimony they gave police.

The comment about the boat's insurance is unfair in two respects; firstly it is implying that not all efforts were made to save the boat. Secondly, exactly the same comment could be made about lightweights that were lost....once again, a factor that has not been brought up when discussing the loss of lightweights has been brought up when discussing the loss of a heavyweight.

Where did you find information about the insurance?

We know nothing about the source of the leak except that the skipper says he couldn’t find it, this is no surprise. Identifying the source of a slow leak in a partially flooded vessel requires it to be bailed.

They bailed the boat. They bailed the boat (according to Emerson's testimony) for 12 hours. They got the level low enough for him to check the skin fittings.


"Now this was an older boat, what 25 years old ? Do we have any history of prior damage and repair ? Was it compromised by it’s build quality? It certainly is likely to have had some osmotic problems it may have had some severe delamination."

Did those who denounce the lightweights ask whether the lightweights that suffered problems had "any history of prior damage and repair"?

Did they ask whether the lightweights that suffered problems were "compromised by its build quality"?

(PS Mintanta was built by the well-reputed Swanson yard and I know of not a single other Swanson that has suffered significant structural damage; maybe Matika in the '70 Hobart had a cracked bulkhead IIRC....not bad in recollections spanning 38+ years for a builder who made a significant proportion of the fleet).

Did you ask whether any lightweights that suffered had osmotic problems?

Once again, there are questions that are being asked about a lost heavyweight, that do not seem to have been asked about a lost lightweight.


"Does this deserve to be included in a conclusive analysis as a hullform ‘sunk’ in the 98 S-H as Dovell claimed in his original report, implying that it was sunk in the storm ?"

It suffered its damage in what the owner claimed were 70-80 knots and 10m swells. I would say that was the storm. If the boat sank in calmer conditions isn't that even more evidence that the heavyweights were not immune to bad weather?

You mentioned that S of O and Nadia's crew were rescued - the boats then survived without them. Mintanta's crew were also rescued and she did not survive without them.

Neither of us like high inversion times, I've already agreed to that.


"In contrast there is a tendency amongst many in the racing fraternity to view cruising boats with disdain."

And looking at this forum there is at least as much of a tendency among the cruisers to view racers with disdain.




Taylor’s charts that I posted before are indicative enough to draw some simple conclusions about the suitability of hull-forms with regard to overall length, displacement, and stability. At least indicative enough for some basic recommendations. The inclusion or exclusion of a vessel is not going to significantly alter that."

I think the charts utterly ignore one of the most basic points of any analysis- there were many more lightweights.

Let's not forget that any analysis of types lost must, to be logically and scientifically valid, account for the fact that the heavy boats were very much a minority and therefore as a type they were much less likely to have suffered damage. I cannot see that Taylor's charts have allowed for the fact that the vast majority of the fleet were light.

Of course the vast majority of casualties were light- they were the vast majority of the fleet.

I remain puzzled about Taylor in some ways. I can find no definition of "long keeler" that satisfies his assertion that they made up 11% of the fleet. Secondly, one of the heaviest (and highest LPS) boats either rolled or came very close to it; one of the other heavies (again, with a very high LPS) rolled to an estimated 150 degrees.

Given that one heavy had a ""major major knock down and roll" (to quote her skipper) and another was rolled to an estimated 150, suffered a dismasting, flooding, severe crew injuries and was nearly lost, it seems very strange that Taylor can assert "none of the 11 per cent of the fleet with long keels was rolled”.

He is either ignoring evidence, or using a definition of "rolled" that ignores boats that WERE or may have rolled (according to their skipper and crew) and are dismasted, have badly injured crew, flooding and are almost lost. I would suggest that neither inspire a huge amount of confidence.


PS The reference to the '79 Fastnet was another example of what I believe to be some misplaced emphasis on boat type; one boat that lost two crew has been all but ignored in the post-race analysis, another boat that lost two crew has been used as an example of all that is wrong in design. Yes, they lost them in different ways - but why so much fuss about one way of losing crew, and so little about the other?

 

lets be practical

When you build your own steel boat it is far cheaper than doing it in fibreglass. Details like cleats, mooring bits, anchors, handrails etc are all fabricated in place, with materials from the scrapyard, or left over hull materials, for a tiny fraction the price of purchasing it for a fibreglass boat. The best and cheapest bedding compound ever invented, welding , is not an option for building a fibreglass boat.
I've built dozens of steel boats for people who could never afford a new fibreglass boat, all well within their limited budgets.
Brent