Questions to be asked again

Interesting thoughts, Sailfree. When I mentioned some standard for a yacht's keel to survive hitting a rock or whatever, I wasn't thinking so much about watertightness - after all a sharp object may pierce the hull. I was thinking rather about the keel not actually dropping off. Of course it's not good if the yacht starts to sink, but at least there is a reasonable chance of trying to stem the flow/pump, sending a Mayday, making it on deck, taking to the liferaft and acting an EPIRB etc. If the yacht just turns upside down, perhaps in the middle of the night in cold waters, that is a much more immediately catastrophic situation.

Again, without wanting to speculate about Hooligan's situation, I'd like to say that on the face of it it seems a great achievement of seamanship and preparedness that most of the crew made it into the liferaft and survived!
 
I'd like to first thank Sailfree for his comments regards the delicacy needed when contributing to such a discussion thread. An events like this is absolutely devastating for the loved ones of the poor soul who perished and most humbling to the rest of us.

Sadly there have been a few posts on this forum that would have benefitted from more thought from the poster. Some could have been worded better and frankly, some should not have been posted at all.

There has been a lot of speculation, innevitable I guess as we all try to come to terms with what's happened and think about the implications. The problem with so much speculation is that it obviously lacks the rigour of a formal investigation and could lead us all down blind alleys.

Most of the discussion has been about the loss of the keel which caused the boat to capsize and sent 5 people into the water. From strictly a safety point of view we should not overlook the fact that a lifejacket was found floating in the water. I think we will have to await the outcome of the investigation to know what happened but it's possible we should be worrying more about our lifejackets than our keels.
 
Unfortunately I think you are correct.

I bought my first big boat from a reputable manufacturer but in complete ignorance of any of the design criteria except AVS but I am concerned that after the tragic Sydney to Hobart race where they imposed a rule of a minimum AVS of 115deg so many AWB's are only just above this.

Hence my question about standards. Would it be unreasonable to bring in a EU directive that all new boats sold after say 2010 have a minimum AVS of say 135 deg and min ballast ratio of say 40% and that is before we start thinking about minimum strength of certain components.

Now I appreciate that the above has little bearing on the incident that prompted this thread!

Luckily incidents like this one are still mostly due to groundings/impact keel damage than inadequate design but I do wonder if our legislaters attention would not be more profitably spent looking at these aspects rather than their fixation with alcohol and boating. Surely it is wrong if the ultimate design criteria is can you sell it. As much as I hate legislators it was only after their involvment that car manufacturers improved the design.
 
Again I would speculate on the basis of informing others.

From memory -so forgive any inaccuracies. A couple of years ago a skipper went overboard from a racing yacht near Liverpool, I think about the month of March.

He had a lifejacket on and was quickly picked up but he was staggered by how quickly the cold made him completely incapable of helping himself. It was only a matter of minutes.

Afterwards he wrote a minute by minute account, It was frightening and a big lesson to me and emphasised the need to avoid going overboard at all costs. After reading that I encouraged crew to always wear a lifejacket except when its so warm they would consider going swimming (sunbathing). Always use a harness when you want to and always once we need a reef.

I cannot remember now where i read it but if someone can point to this article/post others may find it informative. Survival time in the water around England in Winter is very little if you dont wear a survival suit (compulsary before getting every helicopter flight to go offshore!). The sad thing its not much better in the spring!

To me its all about gaining knowledge and minimising risks eg I recently decided that my 140 ml round trip on my motorcycle was dangerous when my hands get to cold to quickly hit the front brake. I still ride the bike to work (cold today!) but fitted heated grips!
 
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Hence my question about standards. Would it be unreasonable to bring in a EU directive that all new boats sold after say 2010 have a minimum AVS of say 135 deg and min ballast ratio of say 40% and that is before we start thinking about minimum strength of certain components.


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Boats are capsized by wave action not heeling too far under wind pressure and the conclusion after the 1979 Fastnet was that all boats will capsize given the 'right' breaking wave. The problem back then and maybe still now for some boats is that they were wide saucer like designs with little above deck volume, as a result they were as stable when inverted as right way up. More relevant to the AVS is the area under the curve which relates to this upside down stability. The AVS is a nominal figure and it's relevance varies with boat length too, smaller boats should have higher AVS figures than bigger ones. A lot of people think a high AVS and/or a high ballast ration equates to a 'stiff' boat, it might but then again it probably doesn't. Older boats with what were called wineglass sections (narrow beam, deep heavy longkeel) would have both high ballast ratio and a high AVS yet could be very tender until well heeled, when the ballast weight had some effecetive leverage. Modern boats have more form stabilty, that is to say their shape resists heeling and are stiffer despite lower AVS figures and lower ballast ratios. Ballast ratios too can be misleading, on the older designs the ballast was not as low down, on modern designs keels are deeper, some with a wider base or even a bulb to lower the CofG even more, so more righting moment for less ballast weght.

I'm not sure why we should consider minimum AVS figure at all, or at least any more than they have already taken into consideration. They have nowt to do with keels falling off, nor do I think we have a problem with lots of capsized monohulls in Europe!
 
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I am very disturbed by the amount of supposition which is being expressed by members of the forum.

None of us was there when this incident occured, nor do we know the circumstances.

It is for the MAIB to investigate, and find out what happened, and without the full facts supposition of the type shown in a number of the postings is unhelpfull, and possibly scare mongering.

If you dont know, my suggestion is to zip it, and await the outcome of the enquiry.,

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This is an event that will be discussed in yacht clubs and households up and down the country, I think your suggestion will be universally disregarded. It is your choice if you don't wish to join such discussions and probably best if you avoid them if you find such things disturbing.

The vast majority of people who discuss unfortunate events weren't there and it is perfectly reasonable to use available information. MAIB weren't there and they will certainly be discussing the event and making suppositions taking into account all available information.
 
There have been a number of incidents over the years where discussions on here have followed. On more than one occasion the casualties have been personally known to forumites

I would hope that there will always a general level of respect and sensitivity in these discussions, but they will naturally go on both here and in yacht clubs/bars. I don't have anything specific to contribute over the points already made, but I've seen nothing posted which I felt insensitive. Apart from the silly comments like 'zip it'
 
I know it's making a heck of an assumption, but my guess is that the guys aboard would prefer to know themselves exactly what happened, and to let others know too, on the basis that they'd hate it to happen to anyone else, if it's at all preventable.

In the past when cataclysmic things have happened sometimes it hasn't been too long before we see a first hand account, here on the web, or in one of the magazines.
 
Please check the news reports...

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There has been a lot of speculation, innevitable I guess as we all try to come to terms with what's happened and think about the implications. The problem with so much speculation is that it obviously lacks the rigour of a formal investigation and could lead us all down blind alleys.

Most of the discussion has been about the loss of the keel which caused the boat to capsize and sent 5 people into the water. From strictly a safety point of view we should not overlook the fact that a lifejacket was found floating in the water. I think we will have to await the outcome of the investigation to know what happened but it's possible we should be worrying more about our lifejackets than our keels.

[/ QUOTE ]It would be helpful if you read the news reports more carefully before you add to the speculation. As I understand it, the lifejacket you mention was attached to the dead crewmember. Most news reports included the quote "Chris Winzar, Royal National Lifeboat Institution coxswain at Salcombe, said the search ended when a merchant ship saw a lifejacket floating in the water. "We went to the scene to pick the lifejacket up and sadly found the body of the missing person."
 
Well expressed.

Your post also demonstrates the difficulty of trying to set minimum standards. I merely posted those figure to start the discussion.

I am still under the impression that the bigger the AVS the more unstable a boat is inverted and the quicker it would right itself. An important point if you are hooked on.

Are you aware of any minimum standards that boats are designed to other than the one that was so succinctly put "what will sell"
 
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I am not surprised that America has some standards but are they standards that have the force of law in the USofA or merely recommendations?

Do European boat builders comply with these standards?

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Such standards exist. You need a degree in engineering and material science to understand. It is all very detailed and starts with basic facts about known strength in x mm of GRP laminate, then the standard makes a further adjustment for n degrees of radius in the hull area supporting the keel and so on.

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In the example of the unfortunate Bavaria match there was no manufacturers claim that the keel complied to any standard design criteria.

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There sure was. Bavaria employed some tame scientist who worked up an example using the Euro standard for Bavaria Match 42 dimensions and weights. He "proved" that at 13mm of hull thickness, the Bavaria Match 42 was built 40% in excess of the requirement.

The Euro standards also exhibit a classic example of disconnected committee room thinking. They might specify hull thickness, floor grid member size and keel bolt dimensions but the standards do not take a holistic view about how all these things should be connected. The result is that a manufacture like Bavaria will hang a narrow rooted 2.5 ton performance keel directly off the hull skin on 7 bolts and believe they have overbuilt by a 40% margin.
 
I believe the most valuable feature to make it unstable when inverted is volume in the coachroof area, so your deck salooon is a definite plus!

I'm not personally aware of any standards but I'm sure that designers do have knowledge of and design for the likely forces involved. The ideal man to buttonhole is Andrew Simpson (a PBO man) if you run into him in the bar at PYC, he is a surveyor as well as a designer of both multihulls and monohulls.
 
Re: Losing keels

Remember that the keel falling off is just a symptom of a design failure, not the cause. At the time of the 79 Fastnet I was heavily involved in IOR design, and the problem there was that the keels were very narrow at the top, making it very difficult to support the bending loads as the boat heels. Although no longer working in yacht design, I can see that with a modern high performance design of a small keel and all the weight in a bulb, if attachment is by keel bolts then there may be similar problems, whereas if the keel comes into a supporting structure in the hull then this can be resolved. However on cruising boats like Bavarias there is not this design problem, and their keel failures were probably caused by something totally unrelated.
Tim
 
The standards exist - see here

The requirement for them (or their equivalents) comes from the MCA's coding requirements for commercial / large vessels, and from Annexe 1 of the RCD. There's a useful (brief) summary here, and there is a full copy of annexe 1 to the RCD in annexe B to the MAIB investigation into the structural failure of the 9m RIB "Big Yellow" here . You would probably find the whole investigation in to Big Yellow interesting, as it explains clearly the responsibilities for design approval, etc. ( here ) (Did you know that one of the tests for RIBs is to drop them 3m, for example?). Although a different type of boat, time, place, etc. (and thankfully nobody was killed), you can see that the investigation process might be similar in this case.

I'm not an expert, just interested in preventing failures. As a newcomer to this thread, may I offer my condolences to those reading who have been affected by this incident.

Andy
 
Thanks for that and Jonjo's contribution but from what I have quickly scanned confirms my opinion that there are no standards regarding structural strength. Lots of BS about what must be included on the RCD document etc. The RCD does require structural; calc to be made but I can find no references to what loads to resist.

The first reference are to ANSI codes that are not mandatory in the EU and I am not sure about USA whether they are just considered good practice. I did a quick look but could not identify what forces a hull/keel must resist nor any impact forces. They do cover a multitude of other things. Be careful about USA regs - I smiled over a supermarket warning that the product contained lead and could be injurous to pregnant women and children. The product was shotgun cartridges!!

The MIAB report (as always) was more informative and section 2.8.2 on P41 states " In fact the RCD does not yet specify structural strength standards as the related ISO's are awaiting EC ratification". Next paragraph " Vessels can be considered to satisfy the structural strength requirement by proving that they have a 5 yr safe history" Emperical or what??

My first boat was a early Dufour Classic 36 and one day a man turned up and reinforced the rudder stock area with more GRP. Full marks to Dufour to recognise the problem and do post build mods at their own cost once a weakness was revealed but it supports my view that boats are built on emperical methods the same as early buildings.

For buildings there are minimum loads sopecified both vertical and horizontal for which they must be designed. I am looking for mandatory specification that states a keel and its attachment to the hull must be designed to resist X kn/sqmm as a horizontal force and an impact of the weight of the boat travelling at say 7kts. Similar specification for the rudder stock. I do not believe they exist.

I think boats are like cars , motorcycles and cycles - they on sold on the basis of fit for purpose in that they do not fall apart, Legislation was only introduced for cars when the industry did not clean up its act. From memory the first was a requirement for steering wheels not to move back more than x mm after an impact of X mph (the mini did not comply so hence a new front and the mini clubman). I believe all car legislation is to resist certain impacts but I do not think there is any equivalent for boats. I would be pleased if someone can prove me wrong and point me to the legal requirements.

I would add that specifications do inhibit innovation and development and don't necessarily address the issues eg to clean up car emmissions California asked the manufacturers for the then current emmissions. They legislated by dividing them all by 10. Some of the more difficult ones to achieve were ones that were not those that should have been targeted.
 
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Thanks for that and Jonjo's contribution but from what I have quickly scanned confirms my opinion that there are no standards regarding structural strength. Lots of BS about what must be included on the RCD document etc.

The first reference are to ANSI codes that are not mandatory in the EUC and I am not sure about USA whether they are just considered good practice.

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Sorry, despite having ANSI in the title of the web-page, this is a listing of European ISO standards in the boatbuilding / ship building category.

I'm afraid the link to annexe B of the Big Yellow report is a bit cryptic, as it leads to a document containing several separate annexes. If you wade through to Annexe B (about page 6 of the pdf document) there is a (short!) section on "Essential Requirements"

You are correct that the standard only specifies that the boat must be "designed and constructed" to withstand certain conditions (wind strength and wave height). It doesn't abstract these to pressures and forces. Arguably, this is too dependent on the design in question. There are a plethora of ISO standards referenced later on, but I've never read these (It would cost £1000's for the full set), so I don't know how much design guidance is in them. From looking at a few abstracts, they may be more concerned with test methods, material quality and workmanship, rather than design.

However, encompassing this, there is the requirement (with some exceptions) for the design to be approved by "someone who knows about these things" (my words).

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The MIAB report (as always) was more informative and section 2.8.2 on P41 states " In fact the RCD does not yet specify structural strength standards as the related ISO's are awaiting EC ratification"

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OK, so the standards are there (but not agreed - still a problem, but a different one).

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boats are built on emperical methods the same as early buildings.

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I'm sure you're right, but remember that the building regulations only really codify what had been arrived at empirically over hundreds of years. Similarly things like the MCA codes do the same thing for boats. (I do agree that these are only brought in by implication for leisure boats - either as a means of demonstrating RCD compliance, or by the need for manufacturers to produce boats capable of being MCA coded).

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legislation is to resist certain impacts but I do not think there is any equivalent for boats. I would be pleased if someone can prove me wrong and point me to the legal requirements.

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Not necessarily proving you wrong, but from the MAIB report:

"The RCD also covers the requirements for a ‘Drop Test’ for RIBs up to 8 metres in length. The ISO (ISO 6185-4) covering RIBs between 8 and 24 metres length is currently being drafted...."

I doubt there's an equivalent test for sailing craft, but there may be others. It would be interesting to get hold of a copy of ISO12215 - 1 Small craft -- Hull construction and scantlings -- Part 1: Materials: Thermosetting resins, glass-fibre reinforcement, reference laminate (a bargain at $41!) to see how much 'real' information was in it.

All boats that are sold in the EU should comply with the RCD and it's standards (not just 'fit for purpose'). Although many things seem to be specified in great detail, the design requirements of the RCD seem to hinge on the design being approved by a human being. Whether they do comply, and who checks up on this in practice seems to be a bit of a black hole.

Andy
 
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The MIAB report (as always) was more informative and section 2.8.2 on P41 states " In fact the RCD does not yet specify structural strength standards as the related ISO's are awaiting EC ratification". Next paragraph " Vessels can be considered to satisfy the structural strength requirement by proving that they have a 5 yr safe history" Emperical or what??

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When Bavaria published a keel support reinforcement upgrade for the Match 38’s and 42’s the diagrams were approved by some Euro maritime standards body and had their dated stamp of approval. I do not know whether Bavaria did this to add credence to the retrofit or because they were altering a previously approval design.

As to ISO, RCD and MCA standards my hunch is they are layered over each other to address different needs. ISO specify the core hull engineering and material science stuff, RCD is about how the whole yacht product is configured and the MCA charter coding says starting with an RCD Cat A yacht add anti slip tape to hatch covers and fit an armoured flexible gas line to the cooker.

I would prefer to trust empirical yacht building tradition than junk ISO standards. The whole Bavaria keel saga would have been less murky had Bavaria not been able to quote ISO calculations "proving" their design was sound.

The surveyor I employed to review the keel attachment of my Match 35 was contemptuous of ISO yacht construction standards. He said no yacht builder takes the ISO numbers seriously. Considering that keel support hull thickness varies between +40% and +300% in excess of ISO standards I think the surveyor makes a valid point.

Until the ISO standards are vastly improved they offer no indication how likely it is that a newly manufactured yacht will kill its occupants.
 
Once again both you and Jonjo make interesting contributions.

Your mention of a drop test reminds me of a posting some time ago when some opinioned that a yacht should be designed to be accidentally droped onto concrete when being craned and not suffer any damage.

The context of my post was trying to seek whether there was any minimum impact requirement for keels. eg hitting a rock.

I have gone aground in shingle at about 5kts once and the keel was fine. The previous Jeaneau 43DS to mine hit the cill at Hythe marina very hard (the commissioning manager at the time cracked 2 ribs!- the new owner was helming!). It was quickly lifted out and to everyones utter amazment there was no visible damage. Both these cases are reassuring to me that empirical design works but do wonder whether minimum standards are necessary.

WRT to Jonjo's post - Lloyds once had an approval process but I don't think it ever had the weight of being a necessary statutory document. One hopes that a EU marine body would be competent. WRT to ISO standards I once refused to sign off on a USA prestressing/precast building system being used in Saudi Arabia because I did not like the details and the quality control it required (middle east building standards/concrete quality are not the best). This is why standards are written for minimum requirements but engineers should satisfy themselves that the build quality exists or design in a greater safety margin. Doctors bury their mistakes one at a time unfortunately Engineers mistakes often cause multiple deaths.
 
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