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fred.cosandey

Columbia 32

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What is the current status of the Columbia 32? Have they re-engineered and re-designed their boat?

So far, the track record has been quite frankly scary and dangerous. Broken rudder in California, broken keel and subsequent loss of boat in the Bermuda 1-2, delamination on others…

Nice to see promotional articles in SA, but please exercise due diligence before buying one.

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What is the current status of the Columbia 32? Have they re-engineered and re-designed their boat?

So far, the track record has been quite frankly scary and dangerous. Broken rudder in California, broken keel and subsequent loss of boat in the Bermuda 1-2, delamination on others…

Nice to see promotional articles in SA, but please exercise due diligence before buying one.

 

Vince, some unsolicited advice: you need to address this head on. Quickly. Thoroughly. Publicly.

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I'm not sure we ever found out definitively what happened to the boat abandoned on the atlantic

Yeah, lots of speculation but not much substance. I hadn't heard of delam problems - who is reporting that? and where is the delam occurring?

Brand new one had to abandon race at the start of the ALIR this year as hull began to separate from bulkhead....

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It must drive manufacturers (of all products) batty contending with ambiguous negative claims these days vs 20-30 years ago, online instantly all over the world! Yes, we may have heard some stories but to post like this OP without INCLUDING any substantiation is completely unfair, and it raises doubts that may/not be totally unfounded.

 

How would the OP like it if an anonymous poster called his/her livelihood into question online without any solid evidence? To be put on the defensive and unable to know what potential customers you may have lost?

 

Ain't technology grand, a double edged sword to be sure...

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It must drive manufacturers (of all products) batty contending with ambiguous negative claims these days vs 20-30 years ago, online instantly all over the world! Yes, we may have heard some stories but to post like this OP without INCLUDING any substantiation is completely unfair, and it raises doubts that may/not be totally unfounded.

 

How would the OP like it if an anonymous poster called his/her livelihood into question online without any solid evidence? To be put on the defensive and unable to know what potential customers you may have lost?

 

Ain't technology grand, a double edged sword to be sure...

 

well, we know the rudder came off one of the boats, resulting in a fatality

 

and, we know that a boat was abandoned on the atlantic, with the owner saying there were structural problems

 

I vaguely recall something about the boat in the vineyard race

 

I don't remember hearing about the ALIR issue.

 

As far as I know, the builder has chosen not to address any of these incidents publicly.

 

It seems to me that concern is entirely justified.

 

I doubt I would sail one offshore.

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and, we know that a boat was abandoned on the atlantic, with the owner saying there were structural problems.



I have spoken with the owner. Something, unknown, happened to the keel and the boat would not steer. Hull was perfectly intact. No leaks or cracks.




I vaguely recall something about the boat in the vineyard race.


News to me. There are 2 boats in the NYC area. Which one?


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http://forums.sailinganarchy.com/index.php?showtopic=152885

 

Here's some current discussion from one of the LIS owners who apparently enjoys his boat immensely ...no horse in this race, and I really dig the design...haven't sailed one so no first hand knowledge of the construction.

 

I suppose looks can be deceiving and there are construction or design issues. Whether that's true or not, it would be good to hear some facts.

 

Can somebody who knows full well what happened to the boats chime in and clear the air?

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US Sailing did a full report on Uncontrollable Urge. (Cali)

 

I posted comments from the Solid Air owner in an earlier thread a couple of months ago.

 

and I ain't taking the time to try to find them. Both are old news.

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For those that are concerned-- and in the market to buy one, or sail on one--- Why not just call the builder directly and ask him? It's not like it is very difficult to contact him---

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For those that are concerned-- and in the market to buy one, or sail on one--- Why not just call the builder directly and ask him? It's not like it is very difficult to contact him---

 

I think people are seeking an unbiased view.

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No need to go by hearsay opinions over the internet.

There is a very good construction scantling rule known as ISO 12215. Boats built after 2010 and entering any Cat 0-2 races are supposed to have obtained plan approval from any of the recognized agencies like German Lloyds, DNV, IMCI etc. The cost of plan approval is about the cost of one sail in your inventory and is good for all the boats of that design they produce.

Anyone buying any boat that they plan to race offshore should ask the builder to produce that plan approval certificate or look for it on the ISAF website. If it is an inshore boat, ask to see a printout of the ISO calculations for the hull, keel and rudder. This is not an unreasonable request and any competent, reputable, builder should be happy to comply.

 

For those that are concerned-- and in the market to buy one, or sail on one--- Why not just call the builder directly and ask him? It's not like it is very difficult to contact him---

 

I think people are seeking an unbiased view.

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That's all great - I think you will find that no Columbia 30 or 32 has done a cat 2 (or better) race ever. I am kind of surprised to see that builder putting a "holiday special" up on SA without ever addressing some of the failures that have been rehashed to death here on SA. Not the greatest marketing move I have ever seen.

 

No need to go by hearsay opinions over the internet.

There is a very good construction scantling rule known as ISO 12215. Boats built after 2010 and entering any Cat 0-2 races are supposed to have obtained plan approval from any of the recognized agencies like German Lloyds, DNV, IMCI etc. The cost of plan approval is about the cost of one sail in your inventory and is good for all the boats of that design they produce.

Anyone buying any boat that they plan to race offshore should ask the builder to produce that plan approval certificate or look for it on the ISAF website. If it is an inshore boat, ask to see a printout of the ISO calculations for the hull, keel and rudder. This is not an unreasonable request and any competent, reputable, builder should be happy to comply.

 

For those that are concerned-- and in the market to buy one, or sail on one--- Why not just call the builder directly and ask him? It's not like it is very difficult to contact him---

 

I think people are seeking an unbiased view.

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Columbia Yachts and I have always been committed to the safety and high quality of our boats. The events of the Islands Race accident were thoroughly investigated by an independent committee which compiled a comprehensive 125 page report detailing their findings. The findings did not conclude that the accident was due to any deficiency of the design or construction but did note at least a dozen other factors, not the least of which were the 32 knot winds and violent sea. I was asked to join the crew only days before the race, knowing the predicted conditions. My decision to participate demonstrates my unwavering confidence in the capability of the Columbia 32.

 

Having talked at length with the skipper/owner of the 32 on the Bermuda race, it appears that the boat came in contact with something that kept the boat from making way (even under power). He stated to me that the boat was intact when he left. It wasn't leaking and the keel bolts were tight, but it wouldn’t make way. I will not question his decision to abandon the boat. He told me that he felt he could not resolve the situation and another boat was close by to assist.

 

Both events occurred in difficult conditions and unfortunately there may always be unanswered questions.

 

My family has been building sailboats for 50 years. I've been in rough conditions at sea and I understand what's at stake, hopefully more than you will ever know. I stand behind the quality, engineering, and safety of our boats and I will continue to sail the Columbia 32 with my wife and young family.

 

Vince Valdes

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Columbia Yachts and I have always been committed to the safety and high quality of our boats. The events of the Islands Race accident were thoroughly investigated by an independent committee which compiled a comprehensive 125 page report detailing their findings. The findings did not conclude that the accident was due to any deficiency of the design or construction but did note at least a dozen other factors, not the least of which were the 32 knot winds and violent sea. I was asked to join the crew only days before the race, knowing the predicted conditions. My decision to participate demonstrates my unwavering confidence in the capability of the Columbia 32.

 

Vince Valdes

 

 

This report?

 

http://media.ussailing.org/AssetFactory.aspx?vid=21870

 

Exerpt:

 

 

Panel Findings
1. The accident was caused by the failure of the vessel’s rudder while sailing off a lee shore.

 

And

 

 

Recommendations:
1.Vessels that race offshore should have adequate rudders so that heavy weather sailing conditions do
not cause them to break. This may require plan approval or an inspection from a naval architect or
marine surveyor.

 

Note: Those number "1s" were from the report - hence the #1 cause a was a faulty rudder. Wether that is due to poor design, or build no conclusion is made, but since the Vince has gone on the record saying the design is solid - the only logical conclusion then is poor build quality.

 

What is even scarier is - Uncontrollable Urge had a special rudder that was designed to be stronger then the standard Columbia 32 rudder that has failed in as a little as 10knts of breeze.

 

From the report below:

 

 

Rudder Issues:
The 2013 Islands Race was ISAF OSR Category 3 with Life Raft. There is no plan review required for OSR
Category 3. Tim Kernan, the designer of the Columbia 32, stated “The design of the rudder for the 32 is a standard hollow
rhomboid post, well above ABS requirements”. (Appendix 10) While sailing in 10 knots of wind off Newport
Beach, California Columbia 32 hull #1 broke her rudder with an A2 set. As Gilmore intended to sail Uncontrollable Urge
in Transpac and other offshore races he was concerned about the rudder post strength. Builder, Vince Valdes, built the rudder for Uncontrollable Urge with a solid post instead of the Kernan designed hollow rhomboid tube. Valdes stated “The rudder was designed and built to far exceed ABS specifications. It is a solid carbon post, not a tube, and can’t be compressed."
(Appendix 9 Interview with Vince Valdes)
Before the rudder broke the helmsmen were tiring more quickly than earlier in the race and were only able to
steer for 20 minutes at a time. Cursory examination of Uncontrollable Urge after it washed up on the shore of
San Clemente Island revealed that the rudder shaft had broken just below where the rudder shaft exits
the hull.

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the report is pretty clear: the rudder break didn't kill anyone, but wasting time before calling a pan pan or mayday certainly did.

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A Transpac or Bermuda race is certainly a Cat 2 and people were buying the boats with those races in mind.

The fact that a fiberglass version made the race previously has little bearing since the engineering would need to be entirely redone for Carbon construction. Entirely new construction triggers the need for plan approval, one should not be "grandfathered in".

 

Saying a boat complied with ABS means nothing because it is an outdated rule (last published in 1994) meant for displacement boats. ABS stopped plan review in 1996 for boats not built with their surveyors on site. What people mean is that they believe that the design would have passed were ABS still reviewing plans. ABS allowed one to use material properties higher than normally published if they were verified through testing samples produced in the shop. The problem is that too many are using theoretical values from a computer program with no verification that the shop can build parts to that level.

 

What is wrong with having your design and engineering independently verified as complying with a current international construction standard? It is relatively inexpensive in the grand scheme of things and while it doesn't relieve a builder of liability, it does make it very difficult to prove negligence. The buyer can have some assurance that the engineering has been verified by a recognized independent source. Like ABS in the past, the approved agencies require proof of properties claims that are higher than the nominal values. You can't just show theoretically possible values from a computer program.

 

 

That's all great - I think you will find that no Columbia 30 or 32 has done a cat 2 (or better) race ever. I am kind of surprised to see that builder putting a "holiday special" up on SA without ever addressing some of the failures that have been rehashed to death here on SA. Not the greatest marketing move I have ever seen.

 

No need to go by hearsay opinions over the internet.

There is a very good construction scantling rule known as ISO 12215. Boats built after 2010 and entering any Cat 0-2 races are supposed to have obtained plan approval from any of the recognized agencies like German Lloyds, DNV, IMCI etc. The cost of plan approval is about the cost of one sail in your inventory and is good for all the boats of that design they produce.

Anyone buying any boat that they plan to race offshore should ask the builder to produce that plan approval certificate or look for it on the ISAF website. If it is an inshore boat, ask to see a printout of the ISO calculations for the hull, keel and rudder. This is not an unreasonable request and any competent, reputable, builder should be happy to comply.

 

 

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A Transpac or Bermuda race is certainly a Cat 2 and people were buying the boats with those races in mind.

The fact that a fiberglass version made the race previously has little bearing since the engineering would need to be entirely redone for Carbon construction. Entirely new construction triggers the need for plan approval, one should not be "grandfathered in".

 

Saying a boat complied with ABS means nothing because it is an outdated rule (last published in 1994) meant for displacement boats. ABS stopped plan review in 1996 for boats not built with their surveyors on site. What people mean is that they believe that the design would have passed were ABS still reviewing plans. ABS allowed one to use material properties higher than normally published if they were verified through testing samples produced in the shop. The problem is that too many are using theoretical values from a computer program with no verification that the shop can build parts to that level.

 

What is wrong with having your design and engineering independently verified as complying with a current international construction standard? It is relatively inexpensive in the grand scheme of things and while it doesn't relieve a builder of liability, it does make it very difficult to prove negligence. The buyer can have some assurance that the engineering has been verified by a recognized independent source. Like ABS in the past, the approved agencies require proof of properties claims that are higher than the nominal values. You can't just show theoretically possible values from a computer program.

 

 

That's all great - I think you will find that no Columbia 30 or 32 has done a cat 2 (or better) race ever. I am kind of surprised to see that builder putting a "holiday special" up on SA without ever addressing some of the failures that have been rehashed to death here on SA. Not the greatest marketing move I have ever seen.

 

No need to go by hearsay opinions over the internet.

There is a very good construction scantling rule known as ISO 12215. Boats built after 2010 and entering any Cat 0-2 races are supposed to have obtained plan approval from any of the recognized agencies like German Lloyds, DNV, IMCI etc. The cost of plan approval is about the cost of one sail in your inventory and is good for all the boats of that design they produce.

Anyone buying any boat that they plan to race offshore should ask the builder to produce that plan approval certificate or look for it on the ISAF website. If it is an inshore boat, ask to see a printout of the ISO calculations for the hull, keel and rudder. This is not an unreasonable request and any competent, reputable, builder should be happy to comply.

 

Engineering to the ISO 12215 rule has been standard practice in my office since 2009. The C32 scantlings were evaluated under this rule and easily exceed even the most conservative level of ISO calculated laminate properties. Since ISAF requires plan approval for CAT2 races and above, obtaining plan approval is simply a necessity and was planned for the 32 from day one- now in process. While it is true that the ISO rule produces more robust scantlings than the far simpler ABS 1996 offshore rule, this is not always the case, and in my opinion the ISO rule still falls short in many areas-such as accurately reflecting peak impact pressures in high speed planing boats. For this reason we regularly employ heftier scantlings than those reuired by the rule. I am wholly in favor of these ISAF requirements. In the latter days of the ABS rule, all that was needed to show compliance was a letter from the designer and bulder, and this no doubt lead to corners someimes being cut in the race to make yachts lighter and lighter. As an offshore sailor myself I see confidence in the structure of the yacht as a speed-inducing factor. -Kernan

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If you read it on SA it must be true.

 

yourownwords_zps275a4312.jpg

Just so you all know. I have dibbs on Chumble Spuzz as the name for my next boat!

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So now we have the designer and the builder both claiming their confidence in the Columbia 32 - I would certainly expect that. BUT - the fact still remains that one of them busted a rudder as the first failure in a chain that eventually lead to one sailor dying. So somewhere in the chain there was at least one weak link. What has been done to identify this weak link/s and what has been done to fix it?

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So now we have the designer and the builder both claiming their confidence in the Columbia 32 - I would certainly expect that. BUT - the fact still remains that one of them busted a rudder as the first failure in a chain that eventually lead to one sailor dying. So somewhere in the chain there was at least one weak link. What has been done to identify this weak link/s and what has been done to fix it?

 

+1

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Lighten up Francis

 

Swan 45s and J111s both broke rudders right out of the box wen new. It gets fixed. A guy died and that's tragic but lots of times you can't connect the dots like that. Other stuff happened too.

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Lighten up Francis

 

Swan 45s and J111s both broke rudders right out of the box wen new. It gets fixed. A guy died and that's tragic but lots of times you can't connect the dots like that. Other stuff happened too.

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Engineering to the ISO 12215 rule has been standard practice in my office since 2009. The C32 scantlings were evaluated under this rule and easily exceed even the most conservative level of ISO calculated laminate properties. Since ISAF requires plan approval for CAT2 races and above, obtaining plan approval is simply a necessity and was planned for the 32 from day one- now in process. While it is true that the ISO rule produces more robust scantlings than the far simpler ABS 1996 offshore rule, this is not always the case, and in my opinion the ISO rule still falls short in many areas-such as accurately reflecting peak impact pressures in high speed planing boats. For this reason we regularly employ heftier scantlings than those reuired by the rule. I am wholly in favor of these ISAF requirements. In the latter days of the ABS rule, all that was needed to show compliance was a letter from the designer and bulder, and this no doubt lead to corners someimes being cut in the race to make yachts lighter and lighter. As an offshore sailor myself I see confidence in the structure of the yacht as a speed-inducing factor. -Kernan

 

http://www.sailing.org/classesandequipment/offshore/plan_review.php

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Shucks Vince, I'm willing to have you give me a boat, and I'll take out in some gnarly weather to test it for you anytime if it helps!

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Engineering to the ISO 12215 rule has been standard practice in my office since 2009. The C32 scantlings were evaluated under this rule and easily exceed even the most conservative level of ISO calculated laminate properties. Since ISAF requires plan approval for CAT2 races and above, obtaining plan approval is simply a necessity and was planned for the 32 from day one- now in process. While it is true that the ISO rule produces more robust scantlings than the far simpler ABS 1996 offshore rule, this is not always the case, and in my opinion the ISO rule still falls short in many areas-such as accurately reflecting peak impact pressures in high speed planing boats. For this reason we regularly employ heftier scantlings than those reuired by the rule. I am wholly in favor of these ISAF requirements. In the latter days of the ABS rule, all that was needed to show compliance was a letter from the designer and bulder, and this no doubt lead to corners someimes being cut in the race to make yachts lighter and lighter. As an offshore sailor myself I see confidence in the structure of the yacht as a speed-inducing factor. -Kernan

 

http://www.sailing.org/classesandequipment/offshore/plan_review.php

Sounds like Kernan's a step ahead of you.

I hit send before actually finishing. I was suggesting that they get the approval done as 1) They had to do it anyway and 2) it independently verifies that the engineering meets an international standard which should put clients minds to rest. The link is to the page where you can learn more about plan approval and see the boats which actually have it. Tim's statement indicates that, you should be able to find the C32 there any time now.

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So now we have the designer and the builder both claiming their confidence in the Columbia 32 - I would certainly expect that. BUT - the fact still remains that one of them busted a rudder as the first failure in a chain that eventually lead to one sailor dying. So somewhere in the chain there was at least one weak link. What has been done to identify this weak link/s and what has been done to fix it?

 

+1

 

 

Exactly - no body has told us why the rudder on UU broke, and what has been done about it.

 

Are the new boats the same as UU, or are they different?

 

The "Plan Approval Certificate" sounds like a wonderful thing.., but before I sailed offshore on one of these boats, i'd want to know the answers to those questions.

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Lighten up Francis

 

Swan 45s and J111s both broke rudders right out of the box wen new. It gets fixed. A guy died and that's tragic but lots of times you can't connect the dots like that. Other stuff happened too.

 

Sorry guys, but I cannot let this statement pass.

Below is a picture of the test jig for a J-111 rudder stock at Competition Composites. As you can see by the date stamp on the photo this was back in 2010. Every stock is deflection tested to make sure it meets the standard before being shipped

.

post-30777-0-49727400-1385415704_thumb.jpg

 

Before any rudders were assembled, samples of the first stock were taken and sent to Matrix Composites in Melbourne to verify that the resin content and fiber count was correct. To date, there has not been a single failure of a J-111 rudder.

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Lighten up Francis

 

Swan 45s and J111s both broke rudders right out of the box wen new. It gets fixed. A guy died and that's tragic but lots of times you can't connect the dots like that. Other stuff happened too.

 

Sorry guys, but I cannot let this statement pass.

Below is a picture of the test jig for a J-111 rudder stock at Competition Composites. As you can see by the date stamp on the photo this was back in 2010. Every stock is deflection tested to make sure it meets the standard before being shipped

.

attachicon.gifOct4 004.jpg

 

Before any rudders were assembled, samples of the first stock were taken and sent to Matrix Composites in Melbourne to verify that the resin content and fiber count was correct. To date, there has not been a single failure of a J-111 rudder.

Apologies you are right. It was J111 Blast with a rudder post connection issue in the 2011 Marblehead Halifax Race. Not a broken rudder itself.

 

Just after 7 a.m. we contacted the owner of SSM and advised him of our issue and requirements (an immediate haulout needed) along with our ETA. Shawn from SSM met us outside the mooring field and assisted us to the haulout dock.

Just after 10:30 a.m. we were in the slings and our boat was hauled. Our rudder was intact but had slipped down three inches. As it turned out the rudder cap was not bolted to the rudder post (something since corrected on all sisterships).

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I once worked at a big shipyard with an engineer who described to me what he called “The Polish Work Ethic.” This involves working long and hard on a problem and getting the wrong answer. Before anyone takes offense, I should note that this particular engineer was Polish. I mention the Polish work ethic because it is evident that a lot of analysis and testing goes into the design of rudders, yet they still break.


I met one of the engineers at ABS who was involved with their now abandoned effort to develop yacht classification rules. I asked him about the debacle involving the aluminum BOC Challenge boat Imagine. Imagine had experienced hull failure during a trial sail. His explanation was that the design rules simply hadn’t anticipated a hull that flat being sailed that fast in seas that large. The take away message is that there are limits to the applicability of design rules.


An entirely different approach to engineering was once described to me by an engineer who had worked at a yard that built barges. When he started there, he asked an older engineer why a certain part was so thick. The response was that the part had always been made that thick and had never broken.


The safest approach for designing a critical component like a rudder might be to stick with legacy designs that have proven to be robust. If there is a desire to blaze a new trail with new materials and new configurations, perhaps the design load should be something ridiculous, like hanging the whole boat from a crane by a line tied around the rudder.


Okay, I'm done ranting.

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... perhaps the design load should be something ridiculous, like hanging the whole boat from a crane by a line tied around the rudder.

My guess is the carbon Rudder Stock will take that static load easily ... dynamic loading combined with torsional forces on the rudder are quite different.

 

I wouldn't turn down a ride on one in challenging conditions, they look like a lot of fun

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When i hit the lotto i will order my dreamboat, Riptide 41. Thats how rudders should be designed. (Bieker really knows his sh...). Even if a ufo tears a rudder off, at least the boat wont sink.

post-57849-0-04312300-1385563882_thumb.jpg

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Yes, the Columbia didnt sink, but Sweden 45 sank in the ARC rally. It is true, there are pros and cons to everything.

 

 

http://www.worldcruising.com/newsarticle.aspx?page=S634841684422574687&ArchiveID=1&CategoryID=190&ItemID=220927&src=

 

 

 

When i hit the lotto i will order my dreamboat, Riptide 41. Thats how rudders should be designed. (Bieker really knows his sh...). Even if a ufo tears a rudder off, at least the boat wont sink.

the columbia 32 didn't sink when the rudder came off.

 

there are some disadvantages to transom hung rudders. When I did the Greenport last year (with a redesigned transom-hung rudder), I found that occasionally while close reaching a wave would smack the rudder and nothing else, causing minor spinouts. It was unpredictable and a little disconcerting especially as the sun went down. I'm pretty sure that if I had had an inboard rudder I wouldn't have had the same kind of issues.

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... ...

 

I met one of the engineers at ABS who was involved with their now abandoned effort to develop yacht classification rules. I asked him about the debacle involving the aluminum BOC Challenge boat Imagine. Imagine had experienced hull failure during a trial sail. His explanation was that the design rules simply hadn’t anticipated a hull that flat being sailed that fast in seas that large. The take away message is that there are limits to the applicability of design rules.
An entirely different approach to engineering was once described to me by an engineer who had worked at a yard that built barges. When he started there, he asked an older engineer why a certain part was so thick. The response was that the part had always been made that thick and had never broken.
The safest approach for designing a critical component like a rudder might be to stick with legacy designs that have proven to be robust. If there is a desire to blaze a new trail with new materials and new configurations, perhaps the design load should be something ridiculous, like hanging the whole boat from a crane by a line tied around the rudder.
Okay, I'm done ranting.

 

IMHO hanging the boat from the rudder would not be enough. It should be bounced on the rudder and jerked back & forth like a yo-yo trick... not sure even that would approximate stresses in really hard weather.

 

FB- Doug

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... perhaps the design load should be something ridiculous, like hanging the whole boat from a crane by a line tied around the rudder.

My guess is the carbon Rudder Stock will take that static load easily ... dynamic loading combined with torsional forces on the rudder are quite different.

 

I wouldn't turn down a ride on one in challenging conditions, they look like a lot of fun

 

Yeah, it makes sense to design the rudder stock for an impact load, but it would also make sense to restrict the material selection to materials that can endure large plastic strains, such as stainless steel and aluminum, so that in an overload situation the rudder stock might get bent but would remain intact.

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... ...

I met one of the engineers at ABS who was involved with their now abandoned effort to develop yacht classification rules. I asked him about the debacle involving the aluminum BOC Challenge boat Imagine. Imagine had experienced hull failure during a trial sail. His explanation was that the design rules simply hadn’t anticipated a hull that flat being sailed that fast in seas that large. The take away message is that there are limits to the applicability of design rules.
An entirely different approach to engineering was once described to me by an engineer who had worked at a yard that built barges. When he started there, he asked an older engineer why a certain part was so thick. The response was that the part had always been made that thick and had never broken.
The safest approach for designing a critical component like a rudder might be to stick with legacy designs that have proven to be robust. If there is a desire to blaze a new trail with new materials and new configurations, perhaps the design load should be something ridiculous, like hanging the whole boat from a crane by a line tied around the rudder.
Okay, I'm done ranting.

 

IMHO hanging the boat from the rudder would not be enough. It should be bounced on the rudder and jerked back & forth like a yo-yo trick... not sure even that would approximate stresses in really hard weather.

 

FB- Doug

 

Okay, stick with stainless steel and stay well below the fatigue limit.

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... perhaps the design load should be something ridiculous, like hanging the whole boat from a crane by a line tied around the rudder.

My guess is the carbon Rudder Stock will take that static load easily ... dynamic loading combined with torsional forces on the rudder are quite different.

 

I wouldn't turn down a ride on one in challenging conditions, they look like a lot of fun

 

Yeah, it makes sense to design the rudder stock for an impact load, but it would also make sense to restrict the material selection to materials that can endure large plastic strains, such as stainless steel and aluminum, so that in an overload situation the rudder stock might get bent but would remain intact.

Is a rudder lying horizontal with its stock bent like a banana better or worse than no rudder at all? Bent rudder will steer you in circles, no rudder gives your shitty emergency steering the best chance it has.

How many modern boats are designed without a watertight bulkhead between the steering gear and the rest of the cabin? Does the Columbia 32 carbon have a sealed area?

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^^ Are any designers and/or builders actually building rudder stocks that are supposed to fail at a specific load level? If so, do they have test programs to verify that failure actually occurs within a specified tolerance band of the specified load level?

 

It's hard to design anything more complicated than a shear pin to fail at a specific load, especially a composite structure for which there is so much possible variability in fabrication. I have memories of a test program for graphite blow plugs for a tank structure. The failure pressures were unpleasantly inconsistent.

 

I've been in other online discussions of the merits of spade rudders versus rudders supported by skegs. The advocates for spade rudders insist that the engineering of such rudders is well understood, but failures still seem to occur fairly frequently.

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I've been in other online discussions of the merits of spade rudders versus rudders supported by skegs. The advocates for spade rudders insist that the engineering of such rudders is well understood, but failures still seem to occur fairly frequently.

 

You've clearly missed the converations about the engineering of skegs on boats, and how many a skeg was held on with the rudder

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Watertight aft sections cost money. And they make access more difficult. And it's an unlikely scenario. Ergo they are not standard options.

If the boat is designed as an offshore race yacht, is it really that unlikely of an event these days? It isnt that hard to do if designed in from the start, our A40RC has a (mostly) watertight section that encompases the steering gear. We put the rubbish bags and fenders in there

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Plan approval is great. Now you just need the builder to build to the plans and to produce products with material properties that the designer assumed. And a 3rd party to occasionally test laminate coupons. If your process changes, or you change resin suppliers, or the 'good' laminator who did the test pieces retires and the new guy adds 20% more resin, or the fabric weight as delivered is too low (not common; usually it's too heavy) the properties of your part might vary a lot. It does give composite engineers headaches.

 

I agree rudder loads are always higher than ABS imagined. And sometimes higher than designers believe.

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Watertight aft sections cost money. And they make access more difficult. And it's an unlikely scenario. Ergo they are not standard options.

If the boat is designed as an offshore race yacht, is it really that unlikely of an event these days? It isnt that hard to do if designed in from the start, our A40RC has a (mostly) watertight section that encompases the steering gear. We put the rubbish bags and fenders in there
Offshore yacht sure. Also submarines. I think he was talking yachts in general. Lots of safety and comfort features get scratched due to weight and cost for competitive reasons on the course and in the marketplace. People also rely on much improved modern rescue probability.

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Watertight aft sections cost money. And they make access more difficult. And it's an unlikely scenario. Ergo they are not standard options.

If the boat is designed as an offshore race yacht, is it really that unlikely of an event these days? It isnt that hard to do if designed in from the start, our A40RC has a (mostly) watertight section that encompases the steering gear. We put the rubbish bags and fenders in there
Offshore yacht sure. Also submarines. I think he was talking yachts in general. Lots of safety and comfort features get scratched due to weight and cost for competitive reasons on the course and in the marketplace. People also rely on much improved modern rescue probability.

That's one of the problems - relying on somebody to bail you out when you get in trouble in a boat not suited to the task at hand - putting yourself, your crew and people trying to help you at risk.

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Watertight aft sections cost money. And they make access more difficult. And it's an unlikely scenario. Ergo they are not standard options.

If the boat is designed as an offshore race yacht, is it really that unlikely of an event these days? It isnt that hard to do if designed in from the start, our A40RC has a (mostly) watertight section that encompases the steering gear. We put the rubbish bags and fenders in there
Offshore yacht sure. Also submarines. I think he was talking yachts in general. Lots of safety and comfort features get scratched due to weight and cost for competitive reasons on the course and in the marketplace. People also rely on much improved modern rescue probability.

That's one of the problems - relying on somebody to bail you out when you get in trouble in a boat not suited to the task at hand - putting yourself, your crew and people trying to help you at risk.

 

 

If I understand correctly, the plan was to sail UU to Hawaii.

 

Had the rudder broken half way there.., it would almost certainly led to an abandonment.., and probably a pretty involved rescue operation.

 

the C32 is not alone in not having a workable emergency steering solution - most boats have nothing that will actually work if needed.

 

I'd love to be proved wrong, but i think most modern race boats are probably not steerable without something pretty closely approaching an actual rudder.

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Re: "relying on somebody to bail you out"

 

Nobody plans on dying that day.

 

But doing a lot of things - from riding a motorcycle to work to going windsurfing on a nice day can put you on the Wrong End of a Rescue.

Can you plan for every emergency scenario ? Please try not to blame the victim too hard on these, Life Will Kill Ya.

 

Sure, don't do reckless stuff, but sometimes things just go very wrong.

 

 

 

Re: "boat not suited to the task at hand"

 

Again, anything can be sunk.

 

I do agree however, and feel that a NEW boat intended for fast offshore passages (high speed + darkness + shorthanding lots of miles + ocean full of Stuff = x number of foil and hull strikes. - feel free to check my math there) should be watertight around the rudder(s) and an effective emergency rudder ought to be standard issue - part of the original design and gear. And a good crash bow. And a keel that stays on ( I'm looking at you, canters...)

 

A story I've told before is one of the old aluminum Waikiki beach cat Leahi - about a month short of her 20th birthday, after near-continuous operations, she hit a Really Big Fish of some sort (not identified) and the aluminum-plate daggerboard that made the contact can-openered the hull, tearing - and flooding very rapidly, taking the whole thing to the bottom in about 60 feet of water in with surprising speed(everyone safely recovered).

 

So a design flaw, you say - it should have had a water-tight compartment around the case, right ? Sure - I needed one on my SuperCat once, I'm with you here...

 

Now apply that to monohulls - watertight bulheads for the rudder, keel, and bow - right ? are you going to put them on EVERY new boat now - and is anyone who goes sailing in any vessel without "relying on Sombody to bail you out ? "

 

Where does it end ? I don't know either.

 

 

Just try not to condemn anybody that needs help as incompetent rubes. I do think the UU guys ought to have had an E-rudder ready to go, but they know that, believe me, they know that. Just like I know you shouldn't windsurf alone.

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Had the rudder broken half way there.., it would almost certainly led to an abandonment.., and probably a pretty involved rescue operation.

Seem to recall that one of Jim Antrim's boats broke both rudders on the way to The Islands. No abandonment. No rescue.

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Had the rudder broken half way there.., it would almost certainly led to an abandonment.., and probably a pretty involved rescue operation.

Seem to recall that one of Jim Antrim's boats broke both rudders on the way to The Islands. No abandonment. No rescue.

We require each boat to be equipped with a tested emergency steering system in the Pac Cup. In the case of California Condor, they had a fully crewed boat of EXTREMELY talented sailors that included the designer. They made their way slowly by dragging and steering a series drogue until the managed a jury rig.

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Finished the 1981 TransPac on Ragtime - sans rudder the last 150 miles--

 

I certainly didn't mean to suggest that no boat that ever lost a rudder ever made it back to shore.

 

but, from what i have read and heard, many boats that lose a rudder in mid-ocean end up abandoned. obviously it depends on the boat, the conditions, the crew etc.

 

i think a modern race boat is going to be much more difficult without an actual replacement rudder

 

i think the very narrow chord keel, and the flatter bottom mean a modern boat just doesn't track as well as an older design

 

going down wind certainly makes things easier.

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There are other happy stories of boats making back home successfully on their own after braking a rudder like the Oakcliff Ker 11.3 in the Newport Bermuda race 2012.

But what is surprising are stories of boats being abandoned as it is a requirement of all offshore races that means of sailing the boat without a rudder have been tested by all crew on board.

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There are other happy stories of boats making back home successfully on their own after braking a rudder like the Oakcliff Ker 11.3 in the Newport Bermuda race 2012.

But what is surprising are stories of boats being abandoned as it is a requirement of all offshore races that means of sailing the boat without a rudder have been tested by all crew on board.

 

I don't know about west coast races.., but on the east coast, this requirement is a joke

 

they will accept basically anything.

 

For the Bermuda race, the "emergency steering system" on more than a few boats is two towed canvas buckets..,

 

i have tested it - in flat water.., and in about 7kts of wind, it kind of works.

 

also - i guess pretty much every boat is "testing" their system with the real rudder still in place - probably locked off!

 

that is a completely meaningless test.

 

as long as we are building boats with rudders that can break off, the requirement should be for an actual replacement rudder.

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I'd love to be proved wrong, but i think most modern race boats are probably not steerable without something pretty closely approaching an actual rudder.

 

Odd statement.

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If I may, I guessing he figures the generally flatter sections of modern performance shapes would be less directionally stable, and thus harder to control than a boat with a lot of V or inherent hull "keel" form or features (wetted chines, strakes, skegs)

 

The difference between a Moore 24 and a Melges 24 without rudders ?

 

Lightning vs. Viper ?

 

The long, very hard chines on Ragtime would seem to lend some 'tracking' nature to the hulls progress, I think - as compared to a TP52 ?

 

I dunno

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If I may, I guessing he figures the generally flatter sections of modern performance shapes would be less directionally stable, and thus harder to control than a boat with a lot of V or inherent hull "keel" form or features (wetted chines, strakes, skegs)

 

The difference between a Moore 24 and a Melges 24 without rudders ?

 

Lightning vs. Viper ?

 

The long, very hard chines on Ragtime would seem to lend some 'tracking' nature to the hulls progress, I think - as compared to a TP52 ?

 

I dunno

 

A modern performance boat is easier all around to steer than any older boat, actual rudder down to no rudder at all with every point in between.

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Finished the 1981 TransPac on Ragtime - sans rudder the last 150 miles--

I certainly didn't mean to suggest that no boat that ever lost a rudder ever made it back to shore.

 

but, from what i have read and heard, many boats that lose a rudder in mid-ocean end up abandoned. obviously it depends on the boat, the conditions, the crew etc.

 

i think a modern race boat is going to be much more difficult without an actual replacement rudder

 

i think the very narrow chord keel, and the flatter bottom mean a modern boat just doesn't track as well as an older design

 

going down wind certainly makes things easier.

I'm willing to wager that very, very few raceboats are abandoned due to rudder loss. I suspect that you're adding cruising boats abandoned during the ARC into your argument. Apples and oranges in terms of crew experience, boat prep, safety rqmts., and willingness to suffer a bit for pride.

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Ever heard of this? You used to be able to buy the little plate for your boat... Oh God my boat is so small and the sea so big.. Remember it? Here, there are some that apparently never have been in the ocean or in a storm.

A boat designer or builder can build a boat to be able to handle every problem in the ocean. But the boat would be so heavy that it would sink. But you wouldn't have any structural problems. And just how long can you tread water?

If you want a place to look for problems is the sacred computer. HUH? Ever see a ship with big signs on the hull that says push here? Wonder why? It use to be ... A 1 inch hull plate works, so just to be safe.. We will use 1 1/4 plate. And you had a heavier ship. Now with the computer... It says that you only need a 7/8 inch plate.. The owner loves you because they can hold more freight...until the ship goes into dock, the tug hits the side just like the old ship, and puts a big dent in it. So they have to find where the ribs are and only let you hit it there.

So now here we sit.. When an owner goes to a designer or a builder, they don't tell them I want the slowest boat in the fleet.. So they go to computers to help them get answers how to make the fastest thing on earth.. And it comes up with answers like carbon fiber for being lighter. And it figures in the loading factor .. But where in the hell does Mother Nature obey loading factors. She is a funny little bitch at times.. Ships sink in storms, keels fall off, masts break, people disappear , and the list goes on.its always happened.. Always will . This is where your brain and common sense comes into play. Like the boat in Southern California .. Ok the rudder shaft broke... What? the guy didn't want to look bad by not requesting a little help? Or That maxi that started to break up from Hong Kong. The World Trade Center was brought down not from the weight of those planes but the fire proofing that was knocked off the steel beams and were over heated and weakened. Just like the failure of that rudder shaft. Was it excessive overloads? Material failure? Hit some unknown object? Or did the computer tell them that what was made would be safe? But like they say SHIT happens, Monday-morning quarterbacks could have won the game last Sunday... And those that know the least.. Think they know the most. Perhaps Columbia has kept us in the dark .. Every think why? Lawsuits? They can't truly come up an answer, because everything that they did was right... But SHIT happens.. And like have said here.. Let's go sailing.. And one needs to QUIT ASSUMING.

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There are other happy stories of boats making back home successfully on their own after braking a rudder like the Oakcliff Ker 11.3 in the Newport Bermuda race 2012.

But what is surprising are stories of boats being abandoned as it is a requirement of all offshore races that means of sailing the boat without a rudder have been tested by all crew on board.

I don't know about west coast races.., but on the east coast, this requirement is a joke

 

they will accept basically anything.

 

For the Bermuda race, the "emergency steering system" on more than a few boats is two towed canvas buckets..,

 

i have tested it - in flat water.., and in about 7kts of wind, it kind of works.

 

also - i guess pretty much every boat is "testing" their system with the real rudder still in place - probably locked off!

 

that is a completely meaningless test.

 

as long as we are building boats with rudders that can break off, the requirement should be for an actual replacement rudder.

 

The variety of what different inspectors will accept is silly. Some will accept a 5 gallon Home Depot bucket on a rode. Others wont accept any bucket arrangements. Meanwhile you have to carry shitloads of ground tackle but there is nowhere to anchor between NPT and BDA.

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... ...

I met one of the engineers at ABS who was involved with their now abandoned effort to develop yacht classification rules. I asked him about the debacle involving the aluminum BOC Challenge boat Imagine. Imagine had experienced hull failure during a trial sail. His explanation was that the design rules simply hadn’t anticipated a hull that flat being sailed that fast in seas that large. The take away message is that there are limits to the applicability of design rules.
An entirely different approach to engineering was once described to me by an engineer who had worked at a yard that built barges. When he started there, he asked an older engineer why a certain part was so thick. The response was that the part had always been made that thick and had never broken.
The safest approach for designing a critical component like a rudder might be to stick with legacy designs that have proven to be robust. If there is a desire to blaze a new trail with new materials and new configurations, perhaps the design load should be something ridiculous, like hanging the whole boat from a crane by a line tied around the rudder.
Okay, I'm done ranting.

 

IMHO hanging the boat from the rudder would not be enough. It should be bounced on the rudder and jerked back & forth like a yo-yo trick... not sure even that would approximate stresses in really hard weather.

 

FB- Doug

 

Okay, stick with stainless steel and stay well below the fatigue limit.

BRONZE ?

no crack corrosion like SS can over time

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There are other happy stories of boats making back home successfully on their own after braking a rudder like the Oakcliff Ker 11.3 in the Newport Bermuda race 2012.

But what is surprising are stories of boats being abandoned as it is a requirement of all offshore races that means of sailing the boat without a rudder have been tested by all crew on board.

I don't know about west coast races.., but on the east coast, this requirement is a joke

 

they will accept basically anything.

 

For the Bermuda race, the "emergency steering system" on more than a few boats is two towed canvas buckets..,

 

i have tested it - in flat water.., and in about 7kts of wind, it kind of works.

 

also - i guess pretty much every boat is "testing" their system with the real rudder still in place - probably locked off!

 

that is a completely meaningless test.

 

as long as we are building boats with rudders that can break off, the requirement should be for an actual replacement rudder.

 

The variety of what different inspectors will accept is silly. Some will accept a 5 gallon Home Depot bucket on a rode. Others wont accept any bucket arrangements. Meanwhile you have to carry shitloads of ground tackle but there is nowhere to anchor between NPT and BDA.

any body try towing an anchor to steer-drag ? or two ?

 

I can't see a bucket lasting very long in a storm [esp one strong enough to break a rudder]

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"any body try towing an anchor to steer-drag ? or two ?" (nota)

 

Not a good idea, a big wave, or two could send that anchor back into your cockpit with a flourish. The rope, anchorline, drouge has the same danger, but fewer hard edges. Like a dinghy on a tow is not a good idea in a seaway, don't tow anything you don't want to get hit with.

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Plan approval is great. Now you just need the builder to build to the plans and to produce products with material properties that the designer assumed. And a 3rd party to occasionally test laminate coupons. If your process changes, or you change resin suppliers, or the 'good' laminator who did the test pieces retires and the new guy adds 20% more resin, or the fabric weight as delivered is too low (not common; usually it's too heavy) the properties of your part might vary a lot. It does give composite engineers headaches.

 

I agree rudder loads are always higher than ABS imagined. And sometimes higher than designers believe.

You must have worked in the industry like me. People would be shocked at how easily composites can and do vary in many shops, just one weak link in the process can have amazingly bad outcomes (imagine when there are several weak links). Fortunately there are some builders with reasonably robust processes, but not all. OTOH, those who've survived are likely worlds better than decades ago.

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Plan approval is great. Now you just need the builder to build to the plans and to produce products with material properties that the designer assumed. And a 3rd party to occasionally test laminate coupons. If your process changes, or you change resin suppliers, or the 'good' laminator who did the test pieces retires and the new guy adds 20% more resin, or the fabric weight as delivered is too low (not common; usually it's too heavy) the properties of your part might vary a lot. It does give composite engineers headaches.

 

I agree rudder loads are always higher than ABS imagined. And sometimes higher than designers believe.

You must have worked in the industry like me. People would be shocked at how easily composites can and do vary in many shops, just one weak link in the process can have amazingly bad outcomes (imagine when there are several weak links). Fortunately there are some builders with reasonably robust processes, but not all. OTOH, those who've survived are likely worlds better than decades ago.
What sort of NDT processes are available for testing structural carbon? I am aware of steel standards, but not composite. Would xray show the required detail? Ultrasound?

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... ...

I met one of the engineers at ABS who was involved with their now abandoned effort to develop yacht classification rules. I asked him about the debacle involving the aluminum BOC Challenge boat Imagine. Imagine had experienced hull failure during a trial sail. His explanation was that the design rules simply hadn’t anticipated a hull that flat being sailed that fast in seas that large. The take away message is that there are limits to the applicability of design rules.
An entirely different approach to engineering was once described to me by an engineer who had worked at a yard that built barges. When he started there, he asked an older engineer why a certain part was so thick. The response was that the part had always been made that thick and had never broken.
The safest approach for designing a critical component like a rudder might be to stick with legacy designs that have proven to be robust. If there is a desire to blaze a new trail with new materials and new configurations, perhaps the design load should be something ridiculous, like hanging the whole boat from a crane by a line tied around the rudder.
Okay, I'm done ranting.

 

IMHO hanging the boat from the rudder would not be enough. It should be bounced on the rudder and jerked back & forth like a yo-yo trick... not sure even that would approximate stresses in really hard weather.

 

FB- Doug

 

Okay, stick with stainless steel and stay well below the fatigue limit.

BRONZE ?

no crack corrosion like SS can over time

 

Yeah, make mine bronze!

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Plan approval is great. Now you just need the builder to build to the plans and to produce products with material properties that the designer assumed. And a 3rd party to occasionally test laminate coupons. If your process changes, or you change resin suppliers, or the 'good' laminator who did the test pieces retires and the new guy adds 20% more resin, or the fabric weight as delivered is too low (not common; usually it's too heavy) the properties of your part might vary a lot. It does give composite engineers headaches.

 

I agree rudder loads are always higher than ABS imagined. And sometimes higher than designers believe.

You must have worked in the industry like me. People would be shocked at how easily composites can and do vary in many shops, just one weak link in the process can have amazingly bad outcomes (imagine when there are several weak links). Fortunately there are some builders with reasonably robust processes, but not all. OTOH, those who've survived are likely worlds better than decades ago.
What sort of NDT processes are available for testing structural carbon? I am aware of steel standards, but not composite. Would xray show the required detail? Ultrasound?

 

That would be a good question for Boeing and their customers. Here are some slides from Japan Airlines < http://events.aviationweek.com/html/mas12/WORKSHOP%203_COMPOSITES_HIROKI_FUKUYAMA.pdf >.

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Cool slide show, thank you for linking - for all us home-shop fiberglassers - just a peak at what you don't know about what you don't know.

 

Remember to heat-relieve the stress on your cold-formed titainium parts !

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I discussed this with my aerospace engineering colleagues. There is a consensus that carbon fiber does not fail in a graceful manner. My colleagues recommend titanium.

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I discussed this with my aerospace engineering colleagues. There is a consensus that carbon fiber does not fail in a graceful manner. My colleagues recommend titanium.

 

Well, no. The yield curve isn't curved.

 

I think this is a lot of the perceived problem with carbon. It's way strong enough (if the design and laminating work are both done correctly) but it doesn't bend. Very counter-intuitive to have this super-duper-strong stuff that doesn't look like it's taking any stress at all ... then suddenly it explodes.

 

FB- Doug

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I think this is a lot of the perceived problem with carbon. It's way strong enough (if the design and laminating work are both done correctly) but it doesn't bend. Very counter-intuitive to have this super-duper-strong stuff that doesn't look like it's taking any stress at all ... then suddenly it explodes.

 

I have a (another) dumb question...

The picture posted by Ryley shows adjustable backstays on the C32 doesn't it? Can a carbon rig be bent with adjustable backstays?

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In order to absorb impact loading you need materials that can deform at least a little i.e with high fracture toughness.

 

For instance, the IMOCA 60 class is moving away from both carbon and titanium for the keel foil design with a recommendation to use a high strength high toughness steel (APX4 steel) for the core plus leading edge of the foil and with a composite aft section.

 

 

 

I discussed this with my aerospace engineering colleagues. There is a consensus that carbon fiber does not fail in a graceful manner. My colleagues recommend titanium.

 

Well, no. The yield curve isn't curved.

 

I think this is a lot of the perceived problem with carbon. It's way strong enough (if the design and laminating work are both done correctly) but it doesn't bend. Very counter-intuitive to have this super-duper-strong stuff that doesn't look like it's taking any stress at all ... then suddenly it explodes.

 

FB- Doug

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Ever tried fly-fishing - or sailed on a boat with a carbon stick? carbon bends nicely - just a matter of engineering whatever bend characteristics into it.

 

I discussed this with my aerospace engineering colleagues. There is a consensus that carbon fiber does not fail in a graceful manner. My colleagues recommend titanium.

 

Well, no. The yield curve isn't curved.

 

I think this is a lot of the perceived problem with carbon. It's way strong enough (if the design and laminating work are both done correctly) but it doesn't bend. Very counter-intuitive to have this super-duper-strong stuff that doesn't look like it's taking any stress at all ... then suddenly it explodes.

 

FB- Doug

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I discussed this with my aerospace engineering colleagues. There is a consensus that carbon fiber does not fail in a graceful manner. My colleagues recommend titanium.

 

Well, no. The yield curve isn't curved.

 

I think this is a lot of the perceived problem with carbon. It's way strong enough (if the design and laminating work are both done correctly) but it doesn't bend. Very counter-intuitive to have this super-duper-strong stuff that doesn't look like it's taking any stress at all ... then suddenly it explodes.

 

FB- Doug

 

have you ever seen a windsurfing mast?

 

they bend plenty without breaking!

 

photo lifted from the iwindsurf forum...

 

tyson_sumo_pic_211.jpg

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I discussed this with my aerospace engineering colleagues. There is a consensus that carbon fiber does not fail in a graceful manner. My colleagues recommend titanium.

 

Well, no. The yield curve isn't curved.

 

I think this is a lot of the perceived problem with carbon. It's way strong enough (if the design and laminating work are both done correctly) but it doesn't bend. Very counter-intuitive to have this super-duper-strong stuff that doesn't look like it's taking any stress at all ... then suddenly it explodes.

 

FB- Doug

No offense Doug, but I'm sailing my second Freedom. The first had two bendy cf masts, the latest has one. In 40 knots with 2 reefs it bends a LOT. Enough that I don't even want to look up the mast and see just how far off the tip is bending, even in 15 knots. My Freedom 40's masts were built in 1980 and showed no signs of failing, and in fact have since carried the new owner safely across the Atlantic to England in what can only be described as "challenging" conditions. The F45's mast was built in 1991 and again, shows no signs of failure despite repeated long distance, heavy weather sailing.

 

In fact, Freedom switched from aluminum to CF because their aluminum freestanding masts were bending.. way too much. Carbon can be engineered to bend, but to the point I'm sure you were trying to make, I'm not sure that's the right engineering for a rudder post, which you mostly don't want bendy, until you absolutely do.

 

thanks, obviously not the smartest thing I've posted

Yes CF can be engineered to bend, my bad...

 

But still as crunch said, it does not have a graceful failure mode even if you're looking at one of those super-bendy bits. Metal bends and gives definite signs of failure, wood bends & splinters, CF just suddenly fails. Of course it fails at a point far above what other material would have failed at but it -didn't- give the warning signs we expect.

 

Back to the rudder post thing- you want a rudder post to be slightly weaker than the back end of the boat. You don't want one to rip the stern off, or to bend and destroy the bearings, or jam at an angle. It seems like it would be possible to engineer a rudder & post that would flex as the load approached the breaking point of the hull itself; then if it had to, go ahead & break off rather than sink the boat. Next question is how to give the skipper warning signs to back off before this all happens.

 

FB- Doug

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I discussed this with my aerospace engineering colleagues. There is a consensus that carbon fiber does not fail in a graceful manner. My colleagues recommend titanium.

 

Well, no. The yield curve isn't curved.

 

I think this is a lot of the perceived problem with carbon. It's way strong enough (if the design and laminating work are both done correctly) but it doesn't bend. Very counter-intuitive to have this super-duper-strong stuff that doesn't look like it's taking any stress at all ... then suddenly it explodes.

 

FB- Doug

No offense Doug, but I'm sailing my second Freedom. The first had two bendy cf masts, the latest has one. In 40 knots with 2 reefs it bends a LOT. Enough that I don't even want to look up the mast and see just how far off the tip is bending, even in 15 knots. My Freedom 40's masts were built in 1980 and showed no signs of failing, and in fact have since carried the new owner safely across the Atlantic to England in what can only be described as "challenging" conditions. The F45's mast was built in 1991 and again, shows no signs of failure despite repeated long distance, heavy weather sailing.

 

In fact, Freedom switched from aluminum to CF because their aluminum freestanding masts were bending.. way too much. Carbon can be engineered to bend, but to the point I'm sure you were trying to make, I'm not sure that's the right engineering for a rudder post, which you mostly don't want bendy, until you absolutely do.

 

thanks, obviously not the smartest thing I've posted

Yes CF can be engineered to bend, my bad...

 

But still as crunch said, it does not have a graceful failure mode even if you're looking at one of those super-bendy bits. Metal bends and gives definite signs of failure, wood bends & splinters, CF just suddenly fails. Of course it fails at a point far above what other material would have failed at but it -didn't- give the warning signs we expect.

 

Back to the rudder post thing- you want a rudder post to be slightly weaker than the back end of the boat. You don't want one to rip the stern off, or to bend and destroy the bearings, or jam at an angle. It seems like it would be possible to engineer a rudder & post that would flex as the load approached the breaking point of the hull itself; then if it had to, go ahead & break off rather than sink the boat. Next question is how to give the skipper warning signs to back off before this all happens.

 

FB- Doug

 

Maybe you engineer the whole thing to handle more than the crew is designed for? :blink:

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Has anybody looked into electrolysis ? Especially when carbon fiber and stainless are connected.. With a wild electric current. That's what all of these experts are saying when you google it.

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I discussed this with my aerospace engineering colleagues. There is a consensus that carbon fiber does not fail in a graceful manner. My colleagues recommend titanium.

 

Well, no. The yield curve isn't curved.

 

I think this is a lot of the perceived problem with carbon. It's way strong enough (if the design and laminating work are both done correctly) but it doesn't bend. Very counter-intuitive to have this super-duper-strong stuff that doesn't look like it's taking any stress at all ... then suddenly it explodes.

 

FB- Doug

No offense Doug, but I'm sailing my second Freedom. The first had two bendy cf masts, the latest has one. In 40 knots with 2 reefs it bends a LOT. Enough that I don't even want to look up the mast and see just how far off the tip is bending, even in 15 knots. My Freedom 40's masts were built in 1980 and showed no signs of failing, and in fact have since carried the new owner safely across the Atlantic to England in what can only be described as "challenging" conditions. The F45's mast was built in 1991 and again, shows no signs of failure despite repeated long distance, heavy weather sailing.

 

In fact, Freedom switched from aluminum to CF because their aluminum freestanding masts were bending.. way too much. Carbon can be engineered to bend, but to the point I'm sure you were trying to make, I'm not sure that's the right engineering for a rudder post, which you mostly don't want bendy, until you absolutely do.

 

thanks, obviously not the smartest thing I've posted

Yes CF can be engineered to bend, my bad...

 

But still as crunch said, it does not have a graceful failure mode even if you're looking at one of those super-bendy bits. Metal bends and gives definite signs of failure, wood bends & splinters, CF just suddenly fails. Of course it fails at a point far above what other material would have failed at but it -didn't- give the warning signs we expect.

 

Back to the rudder post thing- you want a rudder post to be slightly weaker than the back end of the boat. You don't want one to rip the stern off, or to bend and destroy the bearings, or jam at an angle. It seems like it would be possible to engineer a rudder & post that would flex as the load approached the breaking point of the hull itself; then if it had to, go ahead & break off rather than sink the boat. Next question is how to give the skipper warning signs to back off before this all happens.

 

FB- Doug

 

Ummmm, this is called seamanship...

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