Keels and Keels Again!

[Brent Swain]

Stainless is simply not suitable for that application. Had the keel been mild steel it would have probably never cracked. Suggesting that something cheaper would do a better job would be considered sheer heresey to those well programed followers of the consumer religion.
A friend was working at the French Naval base at Kerguelen when one of those boats came in with metal fatigue problems. Phillipe redid the fittings in mild steel believeing that stainless was the cause of the fatigue problem ( as well as the fact that was all he had) She got to Australia with no further problems, where , Phillipe is sure, they replaced their trouble free mild steel fittings with fatigue prone stainless( keeping the faith?)
I remember working on the Brake press many years ago. Scratch a piece of stainless and it would crack from that point the first time you bent a 90 in it. With mild steel you could bend it 90 degrees the wrong way, flatten it out , then bend it 90 the other way with no fear of anything cracking.
Brent

[peter radclyffe]

i agree, even junk diy screws will take more torque than stainless, theres something dangerous about s/s, it pays to almost treat it like cast iron, plastic or ali when using it, it is one of materials of which it can be said with / without irony ," that it is everything it is continually cracked up to be", like an actor, it may become brittle & confused if starved of oxygen & attention , it is the diva of metals

[ancient kayaker]

On the Excalibur yacht sinking, some quotes:-

... a former employee, Derek Harris, who helped Presland (the welder), told the court Presland had had great difficulty making the keel. Heat had to be applied to the two metal coverings of the keel to bend them into shape, he said. But the metal kept buckling and two slits had to be cut into the keel to make it taper properly.

-That sounds like poor design after all.

... significant case, Grimshaw v. Ford Motor Co., 119 Cal. App. Ct. 3d 757, 174 Cal. Rptr. 348 (1981), a California jury required Ford Motor Company to pay $125 million inpunitive damages (later lowered to $3.5 million) to a teenager who was severely burned in a fire that resulted when his Ford Pinto was rear-ended and the fuel tank exploded.

This link has some more words on the Pinto exploding fuel tank story http://www.jacksonprogressive.com/is...ers020706.html
- it makes the point that individuals are frequently found guilty of manslaughter and important individuals within corporations hardly ever are even if they make the decisions leading to a series of fatal accidents. Alex Cittadini, the director of Applied Alloy Yachts which built the yacht Excalibur was found guilty of manslaughter when the poorly welded keel fell off in heavy weather. It is tempting to wonder if he would have got away with it in USA if his company had been big enough to get him a top notch lawyer team.

[CT 249]

I don't know if the decision will hurt sailing as you said in a previous post, AK. Maybe builders and designers will realise that they should worry more about safety.

At least one keel went down here in circumstances were the builder was probably more liable than Cittadini, if you look at the coroner's report. If I recall correctly, the owner wanted a bigger bulb, the designers drew reinforced floors, and the builder claimed (and may have charged) to put in the reinforced floors but didn't bother to do so - leading to a keel and lives lost.

BTW Brent, the consumer religion may have well-programmed followers, but maybe there are other religions in sailing that are just as illogical; who of us can really be sure that we aren't also believers in something that may not be true?

[TeddyDiver]

Originally Posted by CT 249

but maybe there are other religions in sailing that are just as illogical; who of us can really be sure that we aren't also believers in something that may not be true?

Sandwich GRP Marconi rig Racer/Cruiser

[ancient kayaker]

Originally Posted by CT 249

I don't know if the decision will hurt sailing as you said in a previous post, AK. Maybe builders and designers will realise that they should worry more about safety.

I am planning to build a tiny little (10') sailboat this Spring, but even for that I am going into all the safety aspects such as strength, proper seating, righting and re-entry from the water in considerable detail. I don't expect its crew to be tested but it's a matter of pride and it just makes sense.

[peterAustralia]

oops

wrong forum. my apologies

[Earl Boebert]

Decision made in the Skandia lawsuit:

http://www.austlii.edu.au/au/cases/v.../2006/288.html

Cheers,

Earl

[Earl Boebert]

Originally Posted by Earl Boebert

Decision made in the Skandia lawsuit:

http://www.austlii.edu.au/au/cases/v.../2006/288.html

Cheers,

Earl

Oops, botched that one. That was the original decision, overturned on appeal:

http://www.austlii.edu.au/au/cases/v...A/2009/83.html

Cheers,

Earl

[ancient kayaker]

What a truly strange conclusion.

As a system designer I was accustomed to calculate the maximum stresses applicable to each component. I applied standard derating factors for military, aerospace or commercial applications, weighted by the degree of novelty and risk exposure. Then a suitable component was selected from a supplier’s catalog where available.

The derating factor(s) used was spelled out clearly in my design records. It was not the Safety Factor. The SF applied to the product not to the application and is the responsibility of the manufacturer. It ensured that variations in material, manufacture and assembly did not prevent the product from performing as specified by the manufacturer.

For a custom-designed component I might in special cases oversee the product design, but normally I would feel justified in assuming normal practice as far as matters such as SF were concerned, to the degree that I had confidence in my supplier.

But that was back then. If only I had understood what I could safely get away with I could have had a much higher "jobs won" statistic!

So how does this case and it’s judgement stand up to the customs that I was taught? We have an application in which human life depends on the performance of a system that is expressly intended to be subjected to the full fury of Nature under competitive “no quarter given” conditions, analysis for a critical component of this system is based on static forces only (apparently standard and acceptable practice), no component derating applied, inadequate or non-existent design records, a critical component custom-designed at arm’s length, the component supplier apparently applies no SF in the design of his product, and the judge sets aside the design records of one of the World’s leading supplier of such products.

At this point I have very little confidence in the competence of any of the parties involved in this affair, including the judge. I sentence them all to sail forever as crew in an untried boat by an unqualified designer built by the lowest bidder who doesn't understand the designer's language and captained by a complete novice, forever measuring wind forces in the heart of hurricanes. No appeals allowed.

[rwatson]

Well said AK.

The standing joke around all aussie Naval personnel, is that they can have real confidence in their boats, as they have the re-assurance that the vessel was supplied by the lowest-tenderer.

And, having worked on the systems that monitor vessel performance, I can assure you that often no-one has any real knowledge if the guarantees provided by at least one supplier actually stand up to orignal specifications.

This is the age of Enron baby !!!

[Knut Sand]

Originally Posted by rwatson

This is the age of Enron baby !!!

THAT one.... I'll try to remember....
(rotfl... )

[Tad]

Here's the latest from the ISO keel study group....

ISO-DIS-12215-9 keel validation study.pdf

[fcfc]

You can have the draft here http://www.icomia.com/technical-info...t.asp?TI_ID=31

[Guest625101138]

The latest news on the Excalibur incident:
http://news.smh.com.au/breaking-news...0710-dfuw.html

Rick W