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ORR Stability index


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#1 Estar

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Posted 13 February 2011 - 03:30 PM


There is a discussing in the mini forum that touched on the ORR stability index. The following link was given for current stability measurements on various current boats: ORR Scratch Sheet

This data looks really really odd to me.

For starters it shows a stability index of 194.5 degrees for the 12 meter Valiant. Seems to be quite a trick of physics to get an index of greater than 180.

Then we have the 330 boats that will not meet the 115 degree minimum . . . some are obvious but some are odd, like a swan 56 (yes a shoal draft version, but still), Tartan 4100 and 37, Passport 40, Bermuda 40, Alden 54, J35, Antrim 49, Hinckley 43, J44 (Njord), Hood 55, Hans Christian 43, Morris 36, and almost all the famous small short handed Hawaii designs like the Olson 30 and moore 24 . . . I have only picked the ones out that I know have quite a successful (safe) offshore passage making history and experience. Some of these individual boats may have had fit out problems - like placing battery banks to high or such, but the long list of well experienced offshore designs suggests some systematic issue.

So, what's the deal here? Is the methodology crap - not actually measuring stability in a way that is relevant to offshore safety, or is the target crap - too high and screening out boats that have excellent offshore records, or are these boats really marginally stable and have just been lucky during their many safe ocean crossings.

#2 Bob Perry

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Posted 13 February 2011 - 06:06 PM

Evans:
In went thru the list. Most of the numbers make sense but a few jump out at me at being a bit off:
Valiant 40 131.9 degrees I don't think so unless they had the optional 10' fin bulb keel.
Nordic 44 117 degrees, I dont think so unles they had a Mercedes parked on the deck.
Sceptre 43 144 degrees, that's just silly.
Ericson 46 143.8 Degreees, right.

Fun list to look at though.

#3 jhc

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Posted 13 February 2011 - 06:33 PM

ORR uses the same method as the old IOR to find stability. A history of IOR, and TP52 shows how this method has been abused in regard to finding the actual stability of a boat.
IRC (modern handicap) and TP52 have both stopped using this kind of calculation to find stability of a boat .
There is a reason...

#4 Heriberto

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Posted 13 February 2011 - 06:41 PM

How does the TP52 determine stability? IRC is.... well who knows what IRC is, except not friendly to ULDBs (or Minis?).

#5 pogen

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Posted 13 February 2011 - 06:53 PM

Could someone post the formal definition of this number, so we can be sure we are talking about the right thing?

#6 us7070

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Posted 13 February 2011 - 07:57 PM

from memory - i can post the definitionlater if no one else does...

Stability index is not the same thing as LPS - limit of positive stability.

stabilty index is equal to LPS plus two other terms - the capsize increment, and the size increment.

the capsize increment can be negative for really beamy boats, and the size increment is usually (always?) positive.

so stability index is usually greater than LPS

#7 -Nathan-

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Posted 13 February 2011 - 08:13 PM

Stability index is not the LPS.

It is.

Stability Index = LPS+ Capsize Increment(CI) + Size Increment (SI)

Where:

LPS = Limit of Positive Stability.

CI = 18.75*(2-MB/(DSPM/64)^.3333)

SI = (((12*(DSPM/64)^.3333+LSM0)/3.0)-30)/3.0

CI shall not be taken as greater than 5.0 or less than -5.0
SI shall not be taken as greater than 10.0

-Nathan

#8 Greyhawk

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Posted 13 February 2011 - 08:37 PM

MB = max beam?
DSPM = displacement in pounds?
LSM0 = length overall in feet?

#9 pogen

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Posted 13 February 2011 - 08:52 PM

see p. 49

http://www.offshorer...f/orr_nov05.pdf

#10 us7070

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Posted 13 February 2011 - 08:55 PM

LSM0 is the "second moment length" - in measurement trim..., it's complicated...

it's less than the overall length

basically, the stability index, takes the LPS, and then further rewards boats for two things that increase stability - length, and displacement, and penalizes boats for "excess" beam, which decreases ultimate stability, and makes a boat less likely to self-right, if it turns turtle.

#11 0000

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Posted 14 February 2011 - 01:32 AM

The interesting thing about the 12 meter Valiant is it has a Limit of Positive Stability of at least 179.5 degrees, considering the Stability Index of 194.5 and the maximum CI and SI values of 5 and 10.

The ORR Lines Processing Program lacks some accuracy at very high angles of heel because it doesn't account for the volumes of cockpit, coachroof, or deck camber. Even so, I would guess a 12 meter's actual LPS would be close to 170 degrees.

#12 Bobsled

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Posted 14 February 2011 - 03:08 AM

The thing that bugs me about the index is that it is being used to exclude perfectly good and safe boats from races like the LA TransPac. There are boats with long histories of safe ocean races off the West Coast that are kicked to the curb because race organizers are TOO LAZY to do their homework. They instead grasp one of these faulty indices to write their rules. This trend must be stopped.

#13 0000

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Posted 14 February 2011 - 03:37 AM

A lot of work has been done to develop stability standards for sailing yachts, but there is still a ways to go before all types of boats are to be considered fairly.

The standards are based on static righting arm curves of existing boats known to have performed well or poorly from a stability standpoint. The standards themselves can be likened to a statistical analysis of a certain data base. The standards may be faulty for boats that fall outside the range of the data base.

The bottom line is it appears to me that small light boats may be unfairly penalized, and very wide boats with heavy bulb keels may be able to exploit stability criteria such as ISO 12217-2.

#14 Estar

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Posted 14 February 2011 - 03:46 AM

The index definition is interesting but does not really answer my questions. Which are basically threefold:

- Does this number/measurement really mean anything useful for offshore safety when so many boats with good offshore records score so 'poorly'? As I understand the calculation, the LPS will usually be less than this stability index, which means the calculated LPS for many of these boats will be around 90 degrees . . . I find that hard to believe. I really don't believe these boats are going to continue to roll over upside down if you pull the mast to the water level. I also look at Emily (a 40' CCA/IOR centerboard era design) that has a 128 index and wonder how it is so much better than these other boats, just does not seem reasonable. As I understand it, ORR measures low angle (1 or 2 degree) righting moment with its incline test and then using hull shape tries to calculate high angle (120 degree) LPS - is there some extrapolation problem here?

On the bigger picture, I also am not sure if I believe this index really quantifies capsize resistance - the French Ovni's have an excellent record offshore and they have miserable numbers - one theory (which I have no opinion on) is that they don't have a keel to trip over and slide rather than roll.

- How was 115 set as the cut-off point, was there any empirical tank testing or analysis of capsize incidents offshore? Or was the 115 just picked out of a hat. Do I remember correctly that its objective was to limit the time a capsized boat is upside down to less than 2 minutes? If so, is there any empirical evidence that it does that?

- Why do a few of the individual numbers seem so out of whack? Are there errors, or are those individual boats somehow really out of the ordinary?

This is a key screening requirement for our offshore fleet. I am surprised it seems so at odds with my impressions of actual experiences offshore.

#15 0000

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Posted 14 February 2011 - 04:16 AM

Since CI can be negative, I would not assume boats with low stability index numbers have an LPS lower than the stability index.

Inclining experiments are good. The key measurement derived from an inclining is metacentric height which is used to determine the vertical center of gravity. Freeboard measurements are used to determine the as-measured weight and longitudinal center of gravity. Accurate righting arm curves can be generated for various load conditions knowing the as-measured weight and center of gravity. The stability report I prepared for an 85 ft Navy torpedo retriever I designed has over 100 pages of this stuff.

As stability criteria go, the ORR stability index is a weak one and it's just not worth driving yourself batshit crazy trying to make sense of it. ORC generated righting arm curves lose accuracy at heel angles greater than deck edge immersion. The Limit of Positive Stability in perfectly calm water with no wind is not the holy grail of stability analysis. There is more to consider such as downflood angle, area under the righting arm curve to various angles of heel, magnitude of maximum righting arm, angle of heel at maximum righting arm, residual righting arm/heeling arm area ratios, and so on.

ISO 12217-2 is a more complete criterion and is a step in the right direction, but small boats with good safety records are getting hammered.

#16 naca6716

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Posted 14 February 2011 - 05:57 AM

As stability criteria go, the ORR stability index is a weak one and it's just not worth driving yourself batshit crazy trying to make sense of it.


Even when you dropped close to 2 grand on stability calculations for a Transpac boat, just to find out it doesn't pass?

#17 dogwatch

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Posted 14 February 2011 - 06:02 AM

IRC is.... well who knows what IRC is


In this case anyone who can be bothered to find out knows exactly what it is. IRC certificates now show a STIX value which is calculated according to ISO 12217 Part 2. If you are motivated to spend 66CHF you can buy that particular international. standard. http://www.iso.org/i...?csnumber=55958

#18 us7070

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Posted 14 February 2011 - 11:28 AM

The thing that bugs me about the index is that it is being used to exclude perfectly good and safe boats from races like the LA TransPac. There are boats with long histories of safe ocean races off the West Coast that are kicked to the curb because race organizers are TOO LAZY to do their homework. They instead grasp one of these faulty indices to write their rules. This trend must be stopped.


well, if the only thing stopping us from having a better measure of yacht safety offshore, is laziness..., it will be easy for you to come up with an alternative.

a "history of safe ocean races" sounds a bit fuzzy - how would it be applied?

maybe the boats never saw any rough weather on those races.

as i understand it, the stability index is mostly concerned with the likelihood of a boat being rolled by a wave, and then..., if it gets stuck upside down..., whether it will get righted by another wave before the crew (presumably tethered in the cockpit) drown.

given that very very few boats ever face this scenario offshore, it is just not possible to use a past history of racing to evaluate safety relative to this standard.

perhaps you are proposing that the standard be dropped - maybe, since so few boats (could it be zero boats?) have been rolled by waves in the transpac, the standard just isn't relevant...

ok..., lets say you want to drop that standard..., can you tell us - even qualitatively - what kind of standard you would like to see? perhaps just a lower cutoff for shorter boats?

i think it's the capsize increment - which penalizes beamy boats that seems to cause a lot of trouble - these boats are much more stable upside down than narrow boats, so the standard is just doing its job when it identifies these boats.

perhaps this scenario is just too rare to have so much importance in a stability index

I agree with paul - about the coach roof issue - i think the LPS is generated from the measurements the same way it was done for IMS,and it does not include buoyancy from the coach roof, which (in theory) makes a boat both less likely to capsize, and quicker to right.

off course one problem is that it's impossible to design a simple one-number index that will tell you what happens when a boat gets hit by an ocean wave big enough to roll it...

#19 Estar

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Posted 14 February 2011 - 01:22 PM

maybe the boats never saw any rough weather on those races.


Bollocks, just to pick one example . . .

The Bermuda 40 (index = 110) is a CCA blue water medal winner (Bob and Beth Lutz) - cape horn, arctic and antarctic - they saw some bad weather. And by the way, this is a narrow boat, so the beam add-on factor is not the problem. They used to lie ahull, which is a shitty technique, and the fact the boat managed that is a an indication that the boat is a good stable sea boat. This is saying that the B40 is NOT a safe boat to go to Bermuda or Hawaii in?? I have a bit of a problem when the safety community tells us that a bluewater medal boat is not safe to sail to Bermuda!

and on the data integrity . . .Valiant 40 Sovereign index = 116, Valiant 40 Apogee index = 132 What??? Bob says there is a problem here and he should know.

and Morris 47 Raindeer (larger, fixed fin bulbed keel, index = 115.2 (wonder what tricks Neubold went thru to get that extra .2), while Emily (custom 40' centerboard) = 128. Now I like Emily, but mo way in a million years is raindeer the less competent offshore boat.

And Hylas 46 index = 154 is safer/more stable than transpac 52 Flash index = 134??

Would you feel 'safer' going to Hawaii on a hunter 38 index = 134 or a Swan 65 index = 132?? And would you feel equally 'safe'/stable on a J125, which has the same index??

Again, #1 We happen to know quite a few boats that have been knocked down and over - the Southern ocean is a tough task master, and I think I can safely say there is essentially no correlation to this index. And #2 there seems to be a significant data integrity problem.

We have a calculation here that is a bad extrapolation (it goes wrong at about 40 degrees once the deck edge is immersed but pretends to be ok all the way to 180 degree) and then we add on two completely adhoc factors and then we pick a cut-off point out of thin air - and we use this as the main design safety screening factor for our offshore boats??

As to 'an alternative', does anyone have similar calculations/data for a range of boats using the ISO standard? Be interesting to see if its results pass the sniff test any better than this.

Lets say that the objective is to set a minimum standard for how long a boat will stay upside down - there are both better theoretical ways to do that (for instance the ratio of the area of the positive part of the stability curve to the negative part) and much simpler ways (for instance the old capsize screening formulas).

#20 us7070

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Posted 14 February 2011 - 02:14 PM


maybe the boats never saw any rough weather on those races.


Bollocks, just to pick one example . . .



i was speaking specifically about the boats that bobsled said had a history of safe transpacs, but didn't meet the ORR criteria.

i'm not sure that race has seen a lot of bad weather in recent years.

he didn't say what boats he was talking about, but i would not be surprised if there were some boats that i would agree are safe offshore boats, in that list.

so, i do definitely agree that generally speaking, there are some good offshore boats that don't meet the criteria, but that doesn't mean that all the boats that don't meet it are safe, and the problem is how to write a standard that distinguishes them.

i don't want to sound like a cheerleader for the ORR stability index.

i'm just asking: what's the alternative?

i'm not surprised to hear that there is no correlation between the index and likelihood of being knocked down - first of all, it is a relatively rare event, so there won't be much real-world "data" for any one hull, and second, it is such a complex, dynamic, event that it would be hard (impossible) for any static measurement to capture the processes involved.

the index is also attempting to capture the re-righting aspect of the problem, and i would love to know how many boats end up in trouble because of a negative capsize index..., which penalizes beam.

older designs like the B40 will presumably not have trouble here, because they are pretty narrow, but i wonder if some of the transpac boats that bobsled is talking about have a problem with this, or if it is just that they are small?

clearly, the mini class tells us that small boats can be very safe offshore.

#21 0000

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Posted 14 February 2011 - 02:53 PM


As stability criteria go, the ORR stability index is a weak one and it's just not worth driving yourself batshit crazy trying to make sense of it.


Even when you dropped close to 2 grand on stability calculations for a Transpac boat, just to find out it doesn't pass?


Especially if you dropped two grand on stability calculations. BTW, and not many people are aware of this, if a boat owner hires a person to do stability calculations on his or her boat in California, the person doing the calculations is required by law to have a professional engineer's license.

#22 0000

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Posted 14 February 2011 - 03:05 PM

Lets say that the objective is to set a minimum standard for how long a boat will stay upside down


There are no static stability calculations that even come close to addressing that issue. Without external forces, a boat will stay upside down forever .....

To meet the above objective the current state of the art is to turn the boat upside down in prescribed conditions and start a stop watch.

#23 Heriberto

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Posted 14 February 2011 - 03:19 PM



As stability criteria go, the ORR stability index is a weak one and it's just not worth driving yourself batshit crazy trying to make sense of it.


Even when you dropped close to 2 grand on stability calculations for a Transpac boat, just to find out it doesn't pass?


Especially if you dropped two grand on stability calculations. BTW, and not many people are aware of this, if a boat owner hires a person to do stability calculations on his or her boat in California, the person doing the calculations is required by law to have a professional engineer's license.


This isn't directed at you Paul as the examples you cite of your own work are quite impressive. It also isn't derogatory of engineers in general, but....

Isn't there a naval architecture license that applies? I realize this is a hijack, but with an engineer's license you can sign off on just about anything, even when you know jack shit about it. I'm rather certain that (if it is the way it is in every other state), it's the person signing off on the calculations that is required to have the license, not necessarily the person doing them ("here junior, I don't know much about this, why don't you do it and I'll sign off"). California was, if not the first, one of, in having licensure for geologists (for example), due to a bad history of engineers who didn't know shit about geology designing things like slope stability and earthquake hazard mitigation. So now there are specialties in geotechnical, geological engineering, etc.. Are there licensed sub-specialties in naval engineering that are required?

The ASCE is certainly good at its job!

#24 Bobsled

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Posted 14 February 2011 - 04:10 PM

I'm just asking: what's the alternative?


No stability index. It's only being required in the LA TransPac to exclude older boats (like the smaller Santa Cruz-era ultralights that were designed pre-ISO standard) and effectively, anything under 35' due to the cutoff at 115.

Pacific Cup, solo TransPac (run for something like 35 years with no losses), the coastal races out of San Fran (notoriously rough) - none require this stuff.

Your answer is just the issue - is an index required to make the race "safer?" For whom? I contend it's for the R/C, not the racers.

#25 Heriberto

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Posted 14 February 2011 - 04:36 PM

I'm just asking: what's the alternative?


ORC Cat 2.....?

#26 us7070

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Posted 14 February 2011 - 05:16 PM

one thing i always wonder about - and i asked it recently in another thread..., is: how repeatable are these inclining test measurements?

if 5 measurers, each with their own equipment, measured the same boats..., how much would the LPS vary?

if you look at the LPS on the ORC certs, you see that sometimes it varies a lot for boats of the same series - more than i think can be explained by differences in how the boat is equipped.

#27 0000

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Posted 14 February 2011 - 06:29 PM




As stability criteria go, the ORR stability index is a weak one and it's just not worth driving yourself batshit crazy trying to make sense of it.


Even when you dropped close to 2 grand on stability calculations for a Transpac boat, just to find out it doesn't pass?


Especially if you dropped two grand on stability calculations. BTW, and not many people are aware of this, if a boat owner hires a person to do stability calculations on his or her boat in California, the person doing the calculations is required by law to have a professional engineer's license.


This isn't directed at you Paul as the examples you cite of your own work are quite impressive. It also isn't derogatory of engineers in general, but....

Isn't there a naval architecture license that applies? I realize this is a hijack, but with an engineer's license you can sign off on just about anything, even when you know jack shit about it. I'm rather certain that (if it is the way it is in every other state), it's the person signing off on the calculations that is required to have the license, not necessarily the person doing them ("here junior, I don't know much about this, why don't you do it and I'll sign off"). California was, if not the first, one of, in having licensure for geologists (for example), due to a bad history of engineers who didn't know shit about geology designing things like slope stability and earthquake hazard mitigation. So now there are specialties in geotechnical, geological engineering, etc.. Are there licensed sub-specialties in naval engineering that are required?

The ASCE is certainly good at its job!


For a long time I was under the impression that a PE license was not required to perfom naval architecture in California because the state has no NA license and "Naval Architect" is not a restricted title. However, the issue came up a few years ago when the company I was working for was engaged to provide mechanical engineering services on a private yacht.

This is directly from the California Board for Professional Engineers:

"This message is being sent in response to our telephone conversation concerning contracting with a private individual for mechanical engineering services to be install on his or her boat. As we discussed, providing engineering services which fall within the definition of mechanical engineering (defined by Section 6731.6 of the Professional Engineers Act) through a contract with a private party for work on his or her property is required to be performed by or under the responsible charge of a licensed mechanical engineer or a mechanical engineering contractor who both provides the design and installation of the mechanical engineering product."

and:

"Stability and structural calculations for a ship or boat would be mechanical engineering ..."

Using one's PE license to sign off on something he or she knows jack shit about is generally frowned upon by the Board. The person signing off on the calculations is required to be in "responible charge" of those calculations.

#28 0000

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Posted 14 February 2011 - 06:53 PM

one thing i always wonder about - and i asked it recently in another thread..., is: how repeatable are these inclining test measurements?

if 5 measurers, each with their own equipment, measured the same boats..., how much would the LPS vary?

if you look at the LPS on the ORC certs, you see that sometimes it varies a lot for boats of the same series - more than i think can be explained by differences in how the boat is equipped.


Those are good questions. In the real world stability tests from everything from party boats to aircraft carriers are done in accordance with the ASTM Standard Guide for Conducting a Stability Test (Lightweight Survey and Inclining Experiment) to Determine the Light Ship Displacement and Centers of Gravity of a Vessel, and the results are repeatable to about 1% of measured values.

Looking at the ORR inclining procedure, it appears that the WD measurement may not always be consistent between inclinings. The spinnaker poles used have to be absolutely horizontal and perpendicular to the vessel centerline with test weights in the initial position. The weights can not dangle from the ends of the poles at all; they must be fixed. I've never witnessed an inclining done this way, but I can see how different measurers can get results that are in different corners of the same ball park.

#29 Heriberto

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Posted 14 February 2011 - 07:58 PM

"Stability and structural calculations for a ship or boat would be mechanical engineering ..."

Using one's PE license to sign off on something he or she knows jack shit about is generally frowned upon by the Board. The person signing off on the calculations is required to be in "responible charge" of those calculations.


Very interesting. So even the calculations themselves are "mechanical engineering"! And all those people wasting their money on naval architecture and yacht design schools! Apparently all yacht designers who practice in California are breaking the law unless they are registerd Professional Engineers in the state! My guess is that is the case in nearly every other state, as the engineering lobby has toiled hard to make every state's laws as identical (and expansive) as possible.

Yikes!

I have worked in the engineering consulting field (and for engineering firms) for over 20 years. Boards may generally frown, but they only have a chance to do that when something "bad" happens. The practice of senior engineers signing off on sub-specialties of which they have only cursory knowledge continues. As I mentioned previously, the licensure of geologists in California happened in direct reaction to the failure of engineers to properly design for slope failures and earthquake mitigation due to their lack of knowledge of these processes. How many mechanical engineers in California specialize in the stability analysis of offshore race yachts?

This is just an excellent example of the effective turf protection by the engineering lobby.

Sorry for the thread hijack.

#30 0000

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Posted 14 February 2011 - 08:20 PM

How many mechanical engineers in California specialize in the stability analysis of offshore race yachts?


Not many who specialize, but plenty who are qualified. There's a lot of mechanical engineers working as naval architects on the commercial side. The disciplines are very close and a lot of colleges and universities offer NA courses as part of an ME curriculum. California has a broad industrial exemption for engineers that can keep unlicensed yacht designers out of trouble. For example, a yacht designer is exempt from licensing requirements if he is contracted as a consultant by a boat builder, but needs to be a PE if he is contracted to do engineering work by a private individual.

#31 Estar

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Posted 14 February 2011 - 10:05 PM

he didn't say what boats he was talking about, but i would not be surprised if there were some boats that i would agree are safe offshore boats, in that list.


I suspect the Olson 30 and Moore 24.

Its a little odd, relatively recently (in the 70's) a 30' boat was considered a pretty substantial offshore boat size, and not any sort of safety concern. Now they are considered 'simply too small'. I suspect we could reinvigorate offshore sailing if we could make 30'er acceptable again. Just look at what has been done with Berrimilla (Brolga 33).

i'm not surprised to hear that there is no correlation between the index and likelihood of being knocked down - first of all, it is a relatively rare event, so there won't be much real-world "data" for any one hull, and second, it is such a complex, dynamic, event that it would be hard (impossible) for any static measurement to capture the processes involved.


It's actually not so rare in the deep south. Just for example, remember that both the singlehanded girls got knocked upside down. But it is a complex dynamic, and in fact probably depends more on the skipper (and crew - crewed boats hand steering get knocked down much less frequently than boats under autopilot) than on the boat design.

How many worldwide races have this sort of requirement? I guess the transpac and the Bermuda race are the only two races in the USA with stability index limits - is the sydney to hobat the only one in Australia? Does the fastnet race have a minimum? Any other races with this sort of requirement.

Did the Ostar (And its other various names) have a stability measurement and limit (for the non-'open class' boats which have had their own 'self-righting' requirement)? Its a tough race and had a pretty decent record (don't know if any sort of incarnation is running currently?).

#32 us7070

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Posted 14 February 2011 - 10:26 PM

NYYC transatlantic race is Cat 1

Marblehead- Halifax is cat 2 - stability index > 110

#33 Presuming Ed

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Posted 14 February 2011 - 11:18 PM

Does the fastnet race have a minimum? Any other races with this sort of requirement.


All RORC races have a stability requirement: RORC NOR: http://www.rorc.org/...nor-part-1.html

1.7 Stability and Safety Indices
In accordance with OSR 3.04.3 the RORC uses minimum stability/buoyancy indices. For yachts competing under IRC either SSS or STIX and AVS Indices are used depending on the series date of the yacht and the Category of the race. Monohull yachts not racing under IRC shall satisfy the RORC that they meet the requirements of other stability indices for the Category of race. In exceptional circumstances the RORC may accept other indicators as to the suitability of the yacht for a given Category of race.

1.7.1 SSS OR STIX AND AVS
Category 1 and 2 races:
Boats with series date of 1995 and later will be categorised under STIX only. Boats with series date before 1995 may be categorised under either STIX or SSS.

Category 3 races:
Boats with series date of 2000 and later will be categorised under STIX only. Boats with series date before 2000 may be categorised under either STIX or SSS.

Category 4 races:
Boats may be categorised under either STIX or SSS.

1.7.2 MINIMUM PERMITTED VALUES
OSR Category
Category 1
STIX minimum 32
AVS minimum130-0.002*m
SSS minimum 35

Category 2
STIX minimum 32
AVS minimum130-0.002*m
SSS minimum28

Category 3
STIX minimum 23
AVS minimum130-0.005*m
SSS minimum15

Category 4
Stix minimum 14
AVS minimum 90
SSS minimum10



#34 pogen

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Posted 14 February 2011 - 11:23 PM

Its a little odd, relatively recently (in the 70's) a 30' boat was considered a pretty substantial offshore boat size, and not any sort of safety concern. Now they are considered 'simply too small'. I suspect we could reinvigorate offshore sailing if we could make 30'er acceptable again. Just look at what has been done with Berrimilla (Brolga 33).


Our whole culture has become paranoid about 'safety' and 'security', with very very little feedback from real risk back to perceived risk. And committees like standards and rules to hide behind because it reduces their liability.

It is a little odd that there is a hard cutoff for something like the stability index, that excludes very well proven designs, and no requirement on crew experience, or condition of the vessel itself.

#35 Bobsled

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Posted 14 February 2011 - 11:24 PM


he didn't say what boats he was talking about, but i would not be surprised if there were some boats that i would agree are safe offshore boats, in that list.

From the other thread.

#36 Bobsled

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Posted 14 February 2011 - 11:33 PM


Its a little odd, relatively recently (in the 70's) a 30' boat was considered a pretty substantial offshore boat size, and not any sort of safety concern. Now they are considered 'simply too small'. I suspect we could reinvigorate offshore sailing if we could make 30'er acceptable again. Just look at what has been done with Berrimilla (Brolga 33).


Our whole culture has become paranoid about 'safety' and 'security', with very very little feedback from real risk back to perceived risk. And committees like standards and rules to hide behind because it reduces their liability.

It is a little odd that there is a hard cutoff for something like the stability index, that excludes very well proven designs, and no requirement on crew experience, or condition of the vessel itself.


Exactly! Below is a quote from the current ISAF Offshore Special Regulations. Either it rests here or race organizers are creating liability for themselves by getting into the safety evaluation business:


1.02 Responsibility of Person in Charge

1.02.1 The safety of a yacht and her crew is the sole and inescapable responsibility of the person in charge who must do his best to ensure that the yacht is fully found, thoroughly seaworthy and manned by an experienced crew who have undergone appropriate training and are physically fit to face bad weather. He must be satisfied as to the soundness of hull, spars, rigging, sails and all gear. He must ensure that all safety equipment is properly maintained and stowed and that the crew know where it is kept and how it is to be used.

1.02.2 Neither the establishment of these Special Regulations, their use by race organizers, nor the inspection of a yacht under these Special Regulations in any way limits or reduces the complete and unlimited responsibility of the person in charge.

#37 us7070

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Posted 14 February 2011 - 11:48 PM

i once looked into buying an aerodyne 38, but the one i was interested in had an aluminum mast..., not the carbon mast that most of the aerodyne 38"s have.

i never saw the ORC certificate, but Roger Martin told me that the boats with aluminum masts don't meet the Cat 1 requirement without some work - apparently the boats with carbon masts just make it. i guess there is a slight difference in LPS.

the aerodyne is quite a beamy boat, and i would guess that it has a negative capsize increment.

the aerodyne is obviously a proven offshore boat..., in the sense that it has done a lot of offshore racing..., and performed well in many races.

but, none of that tells us how well the boat will do when caught by a wave that can roll the boat. anecdotal evidence of sailing in huge seas doesn't necessarily answer the question.

i completely agree that the stability index may not tell us any more than the history does.

but i think if we are going to have this discussion, it's important to understand exactly what the index is trying to accomplish, and that the fact that a design has done a number of transpacs or bermuda races, may not give us much information with which to judge how easily a boat will be rolled or how quickly it will right itself either.

as i said above, it's probably just too complex a phenomenon to judge.

so..., maybe we should just abandon the attempt to judge the likelihood of getting rolled.

#38 Greyhawk

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Posted 15 February 2011 - 01:46 AM

How many worldwide races have this sort of requirement? I guess the transpac and the Bermuda race are the only two races in the USA with stability index limits - is the sydney to hobat the only one in Australia? Does the fastnet race have a minimum? Any other races with this sort of requirement.


From the Notice of Race for the 2010 Lobster Run:

4.3.2 ORR Stability Index (“SI”) shall not be less than 115.0

Both the Marblehead to Halifax Race and the Route Halifax au St. Pierre Race have these requirements:

(ii) Design Category A under ISO 12217-2 and an Angle of Vanishing Stability (AVS)
greater than (130 – (2 x mass)) where mass is the minimum sailing displacement in
tonnes, but always greater than 100°, or
(iii) Minimum RORC-STIX of 32, or
(iv) Minimum RORC Stability & Safety Screening Numeral (SSSN) of 28, or
(v) Minimum ORR Stability Index (STBIX) of 110,



The Annapolis to Newport Race has the following requirements:

3.2 Boats must have either:
(a) An IMS Stability Factor or an ORR Stability Limit of at least 110, or be a true sister ship of a
boat in the US SAILING IMS Master File, or ORR File, that has a Stability Factor of at least 110.
Certification of this requirement will be required on the Certificate of Compliance and
Readiness; or
(B) An IRC SSSN or RORC STIX of 30 or more.



(here's a thread on SSSN and STIX values, with some useful links to understanding what those mean: http://forums.sailin...howtopic=117786)


The Marion-Bermuda Race and the Bermuda 1-2 don't have specific stability requirements that I can see, but do reserve the right to refuse entry to any yacht the RC deems unsuitable. In general most of these races reserver that right regardless of what other requirements they might have.

Did the Ostar (And its other various names) have a stability measurement and limit (for the non-'open class' boats which have had their own 'self-righting' requirement)? Its a tough race and had a pretty decent record (don't know if any sort of incarnation is running currently?).


The OSTAR became the Transat, but the Royal Western Yacht Club recently reincarnated the "Original Singlehanded Transatlantic Race" or OSTAR (for us wingnuts) most recently run in 2009. I don't know what the stability requirements were for that race, but they are also running a Doublehanded version in 2012 (the TWOstar), which has the following requirements:

Boats shall have a SSSN minimum value of 35 or STIX minimum value of 32 and an AVS minimum of
130 - 0.002xm, where m is the minimum sailing weight in kgs. Boats with a series date of 1995 and later
will be categorized under STIX only. Boats with a series date before 1995 may be categorized under STIX
or SSSN.


#39 Estar

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Posted 15 February 2011 - 02:01 AM

All RORC races have a stability requirement: RORC NOR: http://www.rorc.org/...nor-part-1.html


Two things interesting there:

1. the AVS (like LPS I presume?) minimum is a function of boat displacement. For cat 1 there is a hard minimum displacement of 3,000kg, and at 3,000 kg the AVS minimum is 130 degrees, but the minimum declines as the boat displacement rises until at 15,000kg the minimum AVS is 100 degrees. I presume that 100 degree avs is in effect lower than the 115 degree ORR stability index. But they are still penalizing small boats quite heavily.

2. The STIX number is a lash-up calculation of a number of factors with (apparently) arbitrary minimums. Looking at the individual boats, the STIX seems very heavily size dependent. They show the STIX number for 324 boats and 44 do not meet the category A STix minimum. Of those 7 ( First 31.7s/d, Sigma 38, Swan 391, Swan 42, Mumm 36, Oceanis 311, Sigma 33) are over 30 feet . The rest are 30 or under. Comparing this to the ORR list, it looks like the ISO screen is less strict than the ORR for boats over 40' but again penalizes the small boats quite heavily.

So, this system looks just as arbitrary to me and penalizes small boats just as much but would probably let the B40 go to Bermuda.


I guess question #1 is if someone wants to race to Bermuda or Hawaii in a laser should be let them? and #2 If no, then is the minimum 3,000kg displacement the right screening rule. That could still allow what some think is a 'poor design' = big beam and/or low righting moment , but we then get to a matter of opinion, which is not really supported by (for example) the Ovni (or other french flat bottom centerboarders) experience - who have successfully accumulated quite a few miles in very stormy seas in the southern ocean.

#40 us7070

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Posted 15 February 2011 - 02:09 AM

i'm not sure "penalize" is the right word...

displacement, by itself, confers protection against being rolled

i'm sure paul can correct me..., but my understanding is that if two boats have the same LPS, but one displaces more than the other, then according to current thinking on the subject, the one with the greater displacement is less likely to be rolled.

#41 Estar

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Posted 15 February 2011 - 02:12 AM

i'm not sure "penalize" is the right word...

displacement, by itself, confers protection against being rolled

i'm sure paul can correct me..., but my understanding is that if two boats have the same LPS, but one displaces more than the other, then according to current thinking on the subject, the one with the greater displacement is less likely to be rolled.


I am sure that's true. Actually I am sure that displacement and length by themselves have way more to do with capsize resistance than LPS, and that the skipper/crew are way more important that even those. See above, I added/edited during your post the thought that perhaps a minimum displacement is the simple and effective way to go here.

Its interesting to note that wanderer III (Eric Hiscock's first real boat) has now been round the world 5 times, 3 by cape horn and two winters in south Georgia. Its a full keel 30'er.

#42 us7070

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Posted 15 February 2011 - 02:19 AM

you are right - length also helps.

i guess the thing is, if we are going to have some sort of stability standard, the physics of the process dictate that small boats are going to have more trouble meeting the standard than big boats.

it's easy to say "just do away with it", but we should remember how we got here - it was the 1979 fastnet race that really initiated the quest to find a stability standard for race boats.

#43 Greyhawk

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Posted 15 February 2011 - 02:23 AM

Just to throw a little more fuel on the fire, I sorted the US Sailing ORR Scratch Sheet by class, and looked up the class of boat I own and one that is roughly similar in size, but has a different STBIX:

There are 6 Peterson 34's (my boat) with STBIX's ranging from 120.9 to 124.6.

There are 23 J35's with STBIX's ranging from 102.1 to 115.9, with an average of 110.4 Only 3 boats exceed the magical threshold of 115 for Cat 1 races, and 7 boats of the boats don't even meet the 110 threshold for Cat 2 races.

I find the PET34 and J35 interesting to compare because they are roughly similar in size and have nearly identical I,J, and P rig dimensions (though not E).

The PET34 has an IMS Limit of Positive Stability of 121 degrees (according to the circa 1987 USYRU Performance Package that came with my old boat), while the JBoats website reports an LPS of 128 degrees for the J35. In terms of the other parameters that go into the STBIX, the J35 is marginally beamier than the PET34 (11.9 vs. 11.25), they have very similar nominal displacements (10,500 lbs for one, 10,800 lbs for the other), and the J35 is a bit longer (35' vs 34' LOA, and 30' vs. 27.75' LWL).

And yet the PET34 has a higher STBIX... Why the difference? The LPS reported by JBoats may be the designer's calculation which perhaps includes the deck and house, whereas the IMS value for the PET34 is based just on the hull. The J35 is beamier, and although the displacements are similar, lighter for its length.

But are those differences enough to account for the divergence in ORR-STBIX values?

#44 us7070

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Posted 15 February 2011 - 02:32 AM

supposedly..., the difference between IMS LPS (same as ORR) and the "normal" way of calculating it, can be as much as 10 deg

some of that is due to the cabin house, but i think not all of it.

yes, i think most designers use the method that gives the highest value.

#45 Greyhawk

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Posted 15 February 2011 - 02:51 AM

supposedly..., the difference between IMS LPS (same as ORR) and the "normal" way of calculating it, can be as much as 10 deg
some of that is due to the cabin house, but i think not all of it.
yes, i think most designers use the method that gives the highest value.


Yeah, I think I heard it could be as much as 15 degrees, even. So given a designer's LPS of 128 for the J35, the ORR-LPS must be somewhere between 118 to 113 -- they would still have to have a negative CI to get to STBIX's of 110... But maybe the beam and relatively light displacement are enough?

#46 Heriberto

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Posted 15 February 2011 - 04:09 AM

supposedly..., the difference between IMS LPS (same as ORR) and the "normal" way of calculating it, can be as much as 10 deg

some of that is due to the cabin house, but i think not all of it.

yes, i think most designers use the method that gives the highest value.


Why those dastardly "designers"! How dare they pick the least onerous number to describe the stability of their yacht, out of a host of systems that produce numbers which aren't often applicable in the actual seaworthiness/performance of offshore racing yachts!!!?????

Don't they understand that displacement, by itself, confers protection against being rolled? And length too?* Why don't they remember Fastnet? Why do they insist on marching forward with ways to make lighter yachts when we really should be making arbitraty cutoffs based on displacement?

50,000lbs and over 45'. That should do it. Can't roll if you weigh 50,000lbs and over 45'. Well, not usually anyway....




* Though a 100' long sausage of lead is probably ill-advised.

#47 pogen

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Posted 15 February 2011 - 06:04 AM

Well I've had a good look through the old IMS files left to me by my boats previous owner, and it is pretty interesting.

First, I was gratified to find that I have probably the only Olson 34 that is eligible to do the TransPac. Wheeee!

But look how the stability index varies among sisterships:

Range of SI's for sisterships, data from IMS Master File of 1993:
Olson 34 111.2 to 120.0
Olson 40 118.7 to 121.3
Express 34 110.8 to 113.9
Express 37 107.9 to 118.2

Sail an Express 37 to Hawaii? Deathtrap.

There are many many moderate, safe boats that seem to have SIs in the 110 - 125 range. Unfortunately I don't have enough data in digital form for a histogram. But the big variations among sister ships (the Cal 40 varies from 120 to 125 for example) suggests that the method may be 'poorly conditioned' i.e. that small changes in the input parameters can produce significantly large changes in the output.

Thank god for the SSS, there will always be one race at least for the rest of us!

#48 Estar

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Posted 15 February 2011 - 01:27 PM

Why those dastardly "designers"! . . . .


Irony . . . usually no-one gets it and you just get flamed on the interweb :)

But you are I think missing the point of the discussion - the current approach is complex and looks poorly correlated with reality (both between sister ships and with actual and tank testing capsizes). In that situation would a simpler rule not be better, certainly if it is better correlated with reality but even if it is only similarly bad?

But the big variations suggests that the method may be 'poorly conditioned' i.e. that small changes in the input parameters can produce significantly large changes in the output.

Thank god for the SSS, there will always be one race at least for the rest of us!


I have just been looking at the latest Wolfson (who have been at the center of yacht stability assessment thinking) reports. They indicate in one of their reports that the variation in incline test results on 'small' (they deal with ships, so all our boats are small in their eyes) yachts is quite significant - there are a whole number of poorly controlled variables (wind, humidity, pole angle, placement of the test personal on the boat, etc) that cumulative have a meaningful effect on the results.

They also suggest they think the best general formula is Stability range x RMmax ^.5/ 10 x B = size of critical wave. It's interesting that no one is using this recommended formula.

Interestingly, consistent with the thinking about the French centerboard boats, and somewhat contrary to conventional establishment thinking, they conclude that keel depth (everything else being equal) increases capsize likelihood (keel gets caught in wave rotation and 'trips' the yacht).

Finally, they indicate that the wave heights are relatively high (compared to our small yachts) in even mild storms and capsize even the highest rated yacht. +30' waves are common in storms and essentially no normal size yachts have critical wave height stability > 30'.

#49 Heriberto

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Posted 15 February 2011 - 02:45 PM


Why those dastardly "designers"! . . . .


Irony . . . usually no-one gets it and you just get flamed on the interweb :)

But you are I think missing the point of the discussion - the current approach is complex and looks poorly correlated with reality (both between sister ships and with actual and tank testing capsizes). In that situation would a simpler rule not be better, certainly if it is better correlated with reality but even if it is only similarly bad?

But the big variations suggests that the method may be 'poorly conditioned' i.e. that small changes in the input parameters can produce significantly large changes in the output.

Thank god for the SSS, there will always be one race at least for the rest of us!


I have just been looking at the latest Wolfson (who have been at the center of yacht stability assessment thinking) reports. They indicate in one of their reports that the variation in incline test results on 'small' (they deal with ships, so all our boats are small in their eyes) yachts is quite significant - there are a whole number of poorly controlled variables (wind, humidity, pole angle, placement of the test personal on the boat, etc) that cumulative have a meaningful effect on the results.

They also suggest they think the best general formula is Stability range x RMmax ^.5/ 10 x B = size of critical wave. It's interesting that no one is using this recommended formula.

Interestingly, consistent with the thinking about the French centerboard boats, and somewhat contrary to conventional establishment thinking, they conclude that keel depth (everything else being equal) increases capsize likelihood (keel gets caught in wave rotation and 'trips' the yacht).

Finally, they indicate that the wave heights are relatively high (compared to our small yachts) in even mild storms and capsize even the highest rated yacht. +30' waves are common in storms and essentially no normal size yachts have critical wave height stability > 30'.


Hmmm, well, I think if someone uses a word like "dastardly" they are surely being sarcastic. As for whether I am "missing the point of the discussion", uh, no, but thanks for caring.

The point of the discussion is race organizers excluding from offshore events perfectly fine, historically safe race yachts based on criteria with tenuous (at best) connection with actual seaworthiness. Do they bother to explain their rationale? No. What is more, there is already a (admittedly imperfect) perfectly servicable set of criteria for offshore racing (ORC Categories), which are both more inclusive and also more exhaustive.

So now someone is instead proposing yet another single number criteria with tenuous (at best) connection with actual seaworthiness. Displacement. Not Disp/length mind you, just flat out displacement. Ignoring a couple of dozen years of yacht design intended to produce lighter, stronger, more easily driven offshore yachts.

Lead, wood, carbon fiber, feathers, steel, duck fat, the densities might be different, but a pound is a pound so it all weighs the same, it's all just plain old displacement, no need to differentiate. That might get complex. :rolleyes:

Teh .....it buuurrrnnnnsss.

But congratulations, finally here on page 2 we get someone who actually mentions critical wave height! Can Disp/ballast and Disp/SA be far behind?

#50 0000

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Posted 15 February 2011 - 03:04 PM

i'm sure paul can correct me..., but my understanding is that if two boats have the same LPS, but one displaces more than the other, then according to current thinking on the subject, the one with the greater displacement is less likely to be rolled.


The current thinking on the subject is to look at the area under the righting arm curve from 0 degrees heel up to the downflood angle. This is the FDS (Dynamic Stability Factor) in the STIX calculation. Note that AVS is not relevant if the downflood angle is less than AVS. Also, two identical boats will have different FDS values if the downflood points (hatches) are in different locations. Displacement is not part of the FDS calculation, but the square root of length is.

IMO and Navy stability standards have beam winds combined with rolling criteria that consider area ratios between righting and heeling arm curves on a righting arm curve that starts with a negative heel angle of about -15 degrees to account for rolling. The idea is to somehow relate the properties of a static righting arm curve to dynamic conditions.

#51 Estar

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Posted 15 February 2011 - 03:15 PM

Just thinking about the Wolfson conclusions. . . lets stipulate (As their empirical evidence suggests) that there are waves in 'most storms' that can capsize 'most yachts'. In that case, the design requirement should be that those yachts self right as quickly as possible. The screening formula for that would be minimum upside down stability. So, if we take the Wolfson formula and turn it 'upside down' (negative stability range x 180 degree RMmax ^.5/10 x B) we get a formula that provides the minimum wave size/energy that will re-right an upside down yacht. You then set a maximum size based on wave size frequency.

Practically to do this you would need the upside down stability curve, which would require the industry create curves including the deck/cabin trunk and mast, which should not be hard to do using computer drawings and should really be done in any case (the Wolfson specifically notes the major inaccuracy of AVS/LPS based on hull only).

This is quite different than the current approach. It would be interesting to see if it screens in or out a different set of boats. It may be that while this 'upside down' approach is theoretically better, its practical value add it is not worth the effort. It is interesting that the RORC says they do not think the STIX calculation adds any significant value beyond their very much simpler SSS number, but they support it 'in order to conform to international standards'.

The mini is a 'troublesome' boat for any simple stability rule. Lets say we want to allow them, as they are obviously very seaworthy. Their stability test is: the boat should have greater than 45kg righting moment with the boat heeled so the masthead is at water level (with the water ballast in the least favorable position). This is yet another approach, which does seem to work in practice for some quite small and light boats that do lots of serious offshore miles. I would be curious to know if such a simple actual 'pull over' test could be done with roughly the same effort/cost as the ORR hull wanding and incline test? Or how accurate could this be done/estimated with computer calculation? The mini's don't pass the ISO 3000kg minimum displacement rule, and (as I understand it) get a special exception for it for their European races.

The current stability approach is screening out boats that most of us would be happy taking to Bermuda and/or Hawaii. And it does not seem to reflect the latest Wolfsom empirical evidence. And there looks to be a data repeatability/integrity problem. That's not good for the sport. It is obviously a tough problem, but that's not a good excuse for staying with a bad solution that is choking the sport.

#52 Greyhawk

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Posted 15 February 2011 - 05:41 PM

The current stability approach is screening out boats that most of us would be happy taking to Bermuda and/or Hawaii. And it does not seem to reflect the latest Wolfsom empirical evidence. And there looks to be a data repeatability/integrity problem. That's not good for the sport. It is obviously a tough problem, but that's not a good excuse for staying with a bad solution that is choking the sport.


I agree that there is a big problem with reliably determining stability measures in a way that has significance, but I do wonder to what extent the lack of good measures is really "choking the sport." Are there really large numbers of disappointed sailors who are being turned away because their boats don't measure up to the "arbitrary" stability thresholds we have now? OK, I can think of a few examples.

Of course, there are lots of other "safety-related" criteria that are being used to exclude boats from certain events as well (inboard vs. outboard engines; minimum and/or maximum length restrictions, "arbitrary" ratings thresholds, etc...). But these too are leading to capable boats who would otherwise have liked to participate being excluded.

#53 Goonda

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Posted 15 February 2011 - 06:21 PM

Very interesting. So even the calculations themselves are "mechanical engineering"! And all those people wasting their money on naval architecture and yacht design schools! Apparently all yacht designers who practice in California are breaking the law unless they are registerd Professional Engineers in the state! My guess is that is the case in nearly every other state, as the engineering lobby has toiled hard to make every state's laws as identical (and expansive) as possible.

Yikes!

I have worked in the engineering consulting field (and for engineering firms) for over 20 years. Boards may generally frown, but they only have a chance to do that when something "bad" happens. The practice of senior engineers signing off on sub-specialties of which they have only cursory knowledge continues. As I mentioned previously, the licensure of geologists in California happened in direct reaction to the failure of engineers to properly design for slope failures and earthquake mitigation due to their lack of knowledge of these processes. How many mechanical engineers in California specialize in the stability analysis of offshore race yachts?

This is just an excellent example of the effective turf protection by the engineering lobby.

Sorry for the thread hijack.

As someone working towards his PE in Naval Architecture, I know a little about this.

The system varies pretty significantly from state-to-state. The NA PE test is relatively new, so many (most?) states have not adopted a NA PE as a specific license yet. California has not, so NAs in California have to get their mechanical PE to do certain things. In Washington state, they do have a NA specific PE, but it has only been around for a few years.

#54 Bobsled

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Posted 15 February 2011 - 06:42 PM

"Are there really large numbers of disappointed sailors who are being turned away because their boats don't measure up to the "arbitrary" stability thresholds we have now?"

We were, but I won't be specific because I want to lay low. But the bigger concern is that in our area we DON'T have them now (and don't want them).

As one who has raced many thousands of ocean miles, I'm concerned this attempt to legislate safety, especially when the science doesn't support it, has the potential to make ocean racing the domain of the super rich - they can afford the newest (ISO-approved) designs and testing and all the latest "safety" equipment.

As Pogen suggests, I believe this is mostly an attempt by race organizers to reduce their perceived liability. In the case of the LA TransPac it appears to be intended to exclude older and smaller, but competitive boats. If true that's their choice to make, but I wish they would be honest about it. Just say "nothing under 35' or designed before 2001" (or whatever they're wanting to exclude). By requiring a stability standard (quickly shown here to be faulty), they are setting a precedent that I fear other race organizers will blindly follow, and with no benefit. One could even argue they are creating a false sense of security.

#55 0000

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Posted 15 February 2011 - 06:57 PM

As someone working towards his PE in Naval Architecture, I know a little about this.

The system varies pretty significantly from state-to-state. The NA PE test is relatively new, so many (most?) states have not adopted a NA PE as a specific license yet. California has not, so NAs in California have to get their mechanical PE to do certain things. In Washington state, they do have a NA specific PE, but it has only been around for a few years.


Good to hear you're working towards your PE. Almost all states have adopted the NA exam, California being a notable exception. Washington state used to have it's own NA exam which is why almost all small craft designers in Washington are PE's. Yacht designers who were/are Washington state PE's include Ed Monk, Sr., Ed Monk, Jr., Jack Sarin, Bill Garden, Ben Seaborn(?), Paul Bieker, Ray Richards, Howard Apollonio, Bruce Marek, Tim Nolan, and Ben Ostlund.

And there's several Washington PE's working as employees of companies in yacht related businesses. I keep my Washington state license active out of tradition as much as anything else.

You have to be a PE if you want to offer naval architecture services to the public or use the title "Naval Architect" in Washington. It's been that way for at least the last 60 years.

#56 crash

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Posted 15 February 2011 - 07:37 PM

As Pogen suggests, I believe this is mostly an attempt by race organizers to reduce their perceived liability....


I think this has a lot to do with it. Unfortunately (particularly here in america) we have become a culture prone to litigation when something goes wrong. So the race organizers are at risk of being sued for allowing the race to continue in bad weather, or a boat to be entered that was "unsafe" as if that was what caused the loss of life. Rarely do we (as a society) say, "well the skipper was soley responsible" or "The sea is a cruel mistress" or even, "they were aware of the risks"

The aftermath of the 79 Fasnet: In the wake of the disaster, the RYA and RORC commissioned an inquiry. Both organisations reacted rapidly to the disaster to pre-empt any official government inquiry and to demonstrate that sailing was a sport that could govern itself responsibly.

The result was the most far-reaching report ever into the safety and performance of small craft, their crews and their equipment in extreme conditions. It was - and still is - the most definitive work of its kind ever published and much of it is still relevant today. It led to new standards defined in the ORC Special Regulations and brought new ideas to yacht design

or the 98 Sydney-Hobart: State Coroner John Abernethy's 331-page report criticizes the organization of the race management team, and their lack of timely response to a very serious situation. He said the race organizers lacked the necessary knowledge of meteorology and "failed to appreciate the impending storm."


#57 seaker

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Posted 15 February 2011 - 08:22 PM


The current stability approach is screening out boats that most of us would be happy taking to Bermuda and/or Hawaii. And it does not seem to reflect the latest Wolfsom empirical evidence. And there looks to be a data repeatability/integrity problem. That's not good for the sport. It is obviously a tough problem, but that's not a good excuse for staying with a bad solution that is choking the sport.


I agree that there is a big problem with reliably determining stability measures in a way that has significance, but I do wonder to what extent the lack of good measures is really "choking the sport." Are there really large numbers of disappointed sailors who are being turned away because their boats don't measure up to the "arbitrary" stability thresholds we have now? OK, I can think of a few examples.

Of course, there are lots of other "safety-related" criteria that are being used to exclude boats from certain events as well (inboard vs. outboard engines; minimum and/or maximum length restrictions, "arbitrary" ratings thresholds, etc...). But these too are leading to capable boats who would otherwise have liked to participate being excluded.


The boat I race on failed the 115 test over 10 years ago and did not do the Bermuda race until last year when we had it retested and passed easily. So this is a case where poor testing resulted in the boat not doing the race. The tester this time used a electronic averaging incline meter which got a much more precise number. The only reason we retested was I convinced the owner, who is getting older, if we needed to add weight to pass we could take it out after the race and not effect our other ratings.

Ted

#58 Bobsled

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Posted 15 February 2011 - 09:11 PM

Ted, how much did the test cost and what was involved? Did the Bermuda Race committee specify credentials for the person doing the test?

How far below 115 did you think the boat was? Had it been true, were you pretty sure you could get to 115 with internal ballast? How was that estimated/determined?

(While this thread has shown the weaknesses in the required standards, I'm still wondering if I can comply.)

#59 Greyhawk

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Posted 15 February 2011 - 11:28 PM

Hey Ted! I know that boat -- I was on it for the Bermuda race last year! (But Bobsled, I wasn't there for the measuring)

I also know of a Quest 33 that tried to qualify for the last race but couldn't (although I noted that there was another Quest 33 that was in the race). And most of SA knows all about a certain boat that some say went to extraordinary lengths to qualify, with much controversy about whether they still met their one-design class rules.

#60 Joakim

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Posted 18 February 2011 - 01:41 PM

Those are good questions. In the real world stability tests from everything from party boats to aircraft carriers are done in accordance with the ASTM Standard Guide for Conducting a Stability Test (Lightweight Survey and Inclining Experiment) to Determine the Light Ship Displacement and Centers of Gravity of a Vessel, and the results are repeatable to about 1% of measured values.

Looking at the ORR inclining procedure, it appears that the WD measurement may not always be consistent between inclinings. The spinnaker poles used have to be absolutely horizontal and perpendicular to the vessel centerline with test weights in the initial position. The weights can not dangle from the ends of the poles at all; they must be fixed. I've never witnessed an inclining done this way, but I can see how different measurers can get results that are in different corners of the same ball park.


WD is not supposed to be consistent between two different measurements. It is measured when the poles are set to their position with weights on. Of course the poles need to be fixed, but they don't need to be horizontal nor perpendicular. The measured righting moment is within 1% unless the measurement is done in very poor conditions (waves, wind or heavy rain).

I just did a check for one boat assuming a RM 5% too big (error this big would never happen!). The AVS changed 127.3->129.6, stability index 131.9->134.3 and vertical center of gravity lowered by 46 mm.

Another related measurement is the freeboard measurement. For the same 32 footer measuring all freeboards 5 mm too high (a big error) the displacement became 68 kg lighter, AVS changed 127.3->128.0, stability index 131.9->132.5 and vertical center of gravity lowered by 16 mm.

So measuring AVS and stability index is quite consistent. A difference of 5 degrees between two measurements of the same boat can only be due to very bad measurements or more likely a typo while writing down the measurements.

#61 Bob Perry

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Posted 18 February 2011 - 03:08 PM

Joakim:
I have seen stock Valiant 40's with a range of 16 degrees difference ( 112 degreees vs 128 degrees) in AVS. Somebody had to have made a mistake.

#62 Joakim

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Posted 18 February 2011 - 04:18 PM

Joakim:
I have seen stock Valiant 40's with a range of 16 degrees difference ( 112 degreees vs 128 degrees) in AVS. Somebody had to have made a mistake.


I have no idea what is a Valiant 40, since we don't have them here, but after a quick search it seems to be quite old. How do you know they should have the same AVS? Certainly there have been changes in equipment etc. during the almost 40 years. A furling mast maybe?

I looked at some production boats measured here (Finland) and they are typically withing +-2-3 degrees in AVS. I found one exception in which the largest difference between two boats in AVS was 7 degrees, but these boat have been remeasured and the difference is still there. Thus the boats really are that different despite being production boats.

#63 Marvin

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Posted 18 February 2011 - 05:14 PM


Joakim:
I have seen stock Valiant 40's with a range of 16 degrees difference ( 112 degreees vs 128 degrees) in AVS. Somebody had to have made a mistake.


I have no idea what is a Valiant 40, since we don't have them here, but after a quick search it seems to be quite old. How do you know they should have the same AVS?


Joakim, for your reference...

Bob Perry (http://en.wikipedia....(yacht_designer)

Valiant 40 (http://en.wikipedia....ant_40_sailboat)

#64 0000

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Posted 18 February 2011 - 05:19 PM

WD is not supposed to be consistent between two different measurements. It is measured when the poles are set to their position with weights on. Of course the poles need to be fixed, but they don't need to be horizontal nor perpendicular. The measured righting moment is within 1% unless the measurement is done in very poor conditions (waves, wind or heavy rain).


I understand the value of WD does not have to be the same between two different inclinings, but the procedure does. If measurers are able to get accurate WD measurements and consistent results using the ORC inclining procedure, then I won't second guess.

#65 Mikie

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Posted 18 February 2011 - 05:25 PM

I've personally been involved in four inclines...same boat, remeasures for different gear additions etc. AND have to re-incine this year for a new keel and carbon rig that was added/ changed.

If electric inclining meters are used, you get a significantly more accurate measure, IN MY OPINION.

Also in my opinion, there is a huge X factor of who is doing the inclining...and what technique / tools they have developed for the test. The boat I sail has come in anywhere from 112 to 118 - a pretty big swing...

My last though on it, is that for a bulb keel, the incline test to me is less accurate / telling as well..As the boat is not inclined just a few degrees - may 5 -10 tops...which the data generated is then extrapolated in determining the magic degree of re-righting ability...Not sure if this technique / information gathered really accommodates for the effect of a bulb keel and swinging the bulb off center, where the bulb has greater effects for stiffness.

Maybe Bob / some you more techie types can answer, whether the formula accounts for a bulb OR if his formula is so old, that it assumes a fin/ traditional shape of keel??

Mikie

#66 jhc

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Posted 18 February 2011 - 05:38 PM


Joakim:
I have seen stock Valiant 40's with a range of 16 degrees difference ( 112 degreees vs 128 degrees) in AVS. Somebody had to have made a mistake.


I have no idea what is a Valiant 40, since we don't have them here, but after a quick search it seems to be quite old. How do you know they should have the same AVS? Certainly there have been changes in equipment etc. during the almost 40 years. A furling mast maybe?

I looked at some production boats measured here (Finland) and they are typically withing +-2-3 degrees in AVS. I found one exception in which the largest difference between two boats in AVS was 7 degrees, but these boat have been remeasured and the difference is still there. Thus the boats really are that different despite being production boats.

So, "old" boats are expected to be less consistent, stability wise? Or because two boats measured in the same country have "only" two or three degrees discrepancy, the system works?
Give me a break.
The errors that occur with the ORR stability test are not acceptable, and the method should be put to rest.
Was a joke 30 years ago, when used with IOR, and is still a joke.
This "problem" with ORR measurement is the major factor in the rise in popularity of PHRF, IRC, one design, and "open" classes.
As I understand, the 3 degree tip test proscribed by ORR is extrapolated out to find ultimate stability numbers in the range of 100-180 degrees. No compensation for cabintop volumes, sheer configurations, cockpit volumes, removal of the mast by capsize. But the rule can determine the "safety" of canting keel boats?
Give me a break.

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Posted 18 February 2011 - 05:41 PM

My last though on it, is that for a bulb keel, the incline test to me is less accurate / telling as well..As the boat is not inclined just a few degrees - may 5 -10 tops...which the data generated is then extrapolated in determining the magic degree of re-righting ability...Not sure if this technique / information gathered really accommodates for the effect of a bulb keel and swinging the bulb off center, where the bulb has greater effects for stiffness.

Maybe Bob / some you more techie types can answer, whether the formula accounts for a bulb OR if his formula is so old, that it assumes a fin/ traditional shape of keel??


The basic purpose of the inclining experiment is to determine the metacentric height and use that value to calculate VCG. It is based on the assumption that metacentric height is constant at small angles of heel - it's not, but it's close enough. ASTM recommends the angle of heel be 2 to 3 degrees with a maximum of 4 degrees. 5 - 10 degrees is way too much and could lead to erroneous stability data. As long as the hydrostatic calculations are accurate, shape of the hull and keel is irrelevant.

#68 0000

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Posted 18 February 2011 - 05:54 PM

As I understand, the 3 degree tip test proscribed by ORR is extrapolated out to find ultimate stability numbers in the range of 100-180 degrees.


That's not how it works. The underlying principles of naval architecture behind the inclining experiment and stability calculations are sound.

The stability inconsistencies reported in this thread look like a garbage in garbage out type of situation. I have no direct experience or hard data to question the ORR inclining procedure, but I do know such a procedure would not be acceptable to the Coast Guard, ABS, Lloyd's, or MCA for any type of vessel.

#69 jhc

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Posted 18 February 2011 - 06:01 PM


As I understand, the 3 degree tip test proscribed by ORR is extrapolated out to find ultimate stability numbers in the range of 100-180 degrees.


That's not how it works. The underlying principles of naval architecture behind the inclining experiment and stability calculations are sound.

The stability inconsistencies reported in this thread look like a garbage in garbage out type of situation. I have no direct experience or hard data to question the ORR inclining procedure, but I do know such a procedure would not be acceptable to the Coast Guard, ABS, Lloyd's, or MCA for any type of vessel.

OK, not extrapolated, but you agree that the data produced by inclination, and freeboard measurements proscribed by ORR are used in the "rollover" calculation?
And, that is not an acceptable method.

#70 0000

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Posted 18 February 2011 - 06:12 PM

OK, not extrapolated, but you agree that the data produced by inclination, and freeboard measurements proscribed by ORR are used in the "rollover" calculation?
And, that is not an acceptable method.


Yes, I agree the measured data is used in the calculation. I would not use data from an ORR inclining for any "real life" stability calculations.

#71 Joakim

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Posted 18 February 2011 - 10:01 PM



Joakim:
I have seen stock Valiant 40's with a range of 16 degrees difference ( 112 degreees vs 128 degrees) in AVS. Somebody had to have made a mistake.


I have no idea what is a Valiant 40, since we don't have them here, but after a quick search it seems to be quite old. How do you know they should have the same AVS? Certainly there have been changes in equipment etc. during the almost 40 years. A furling mast maybe?

I looked at some production boats measured here (Finland) and they are typically withing +-2-3 degrees in AVS. I found one exception in which the largest difference between two boats in AVS was 7 degrees, but these boat have been remeasured and the difference is still there. Thus the boats really are that different despite being production boats.

So, "old" boats are expected to be less consistent, stability wise? Or because two boats measured in the same country have "only" two or three degrees discrepancy, the system works?
Give me a break.


Every boat is different, even when they come from the same production line and much more different when they have different equipment like furlers, teak deck, different interior etc. So there is no reason to expect to get the very same AVS for all the boats of the same model. 40 year old boats are probably more likely to have been modified in some way than 10 year old boats. How many of the Valiant 40's still have the original mast, engine etc?

#72 Joakim

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Posted 18 February 2011 - 10:24 PM

The stability inconsistencies reported in this thread look like a garbage in garbage out type of situation. I have no direct experience or hard data to question the ORR inclining procedure, but I do know such a procedure would not be acceptable to the Coast Guard, ABS, Lloyd's, or MCA for any type of vessel.


What part of the method would not be acceptable? I know the same system is used e.g. by DNV for CE classification of sailboats. By the same system I mean the measurement of displacement and RM. AVS is likely calculated including the effect of superstructure.

I have been involved in measurements of small ships (e.g. 20 m SAR vessels) and I really don't think the eight shift method used for them is more accurate. I also produce an electronic inclining device, which has been used for both ORC and more official measurements of sailboats, motor boats and small ships around the world (not in USA yet). The electronic inclinometer is not more accurate (only as accurate) than traditional methods in calm conditions, but has some benefits dealing with wind and waves due to averaging.

#73 0000

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Posted 19 February 2011 - 12:52 AM


The stability inconsistencies reported in this thread look like a garbage in garbage out type of situation. I have no direct experience or hard data to question the ORR inclining procedure, but I do know such a procedure would not be acceptable to the Coast Guard, ABS, Lloyd's, or MCA for any type of vessel.


What part of the method would not be acceptable? I know the same system is used e.g. by DNV for CE classification of sailboats. By the same system I mean the measurement of displacement and RM. AVS is likely calculated including the effect of superstructure.

I have been involved in measurements of small ships (e.g. 20 m SAR vessels) and I really don't think the eight shift method used for them is more accurate. I also produce an electronic inclining device, which has been used for both ORC and more official measurements of sailboats, motor boats and small ships around the world (not in USA yet). The electronic inclinometer is not more accurate (only as accurate) than traditional methods in calm conditions, but has some benefits dealing with wind and waves due to averaging.


It's not so much about accuracy as it is about reliability and verification. The ASTM guide requires three measuring devices with three independent measurers and a minimum of seven weight movements. If there's a bad measurement in the mix it stands out like a sore thumb and can be corrected with an additional weight movement on the spot.

With only one measuring device and only two weight movements the ORR procedure lacks the checks and balances built into the ASTM guide to detect and correct human error. One bad measurement with the ORR method and you're screwed without even knowing it. You do have the issue of limited space on a small yacht, but I don't see why there can't be two measuring devices (one can be a pendulum), and at least five weight movements instead of two.

#74 Bob Perry

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Posted 19 February 2011 - 12:55 AM

I wasn't trying to say much of anything. Just that in the early days of the Valiant 40's say around 1980 several were inclined and the results were quite varied. I always figured the LPS was about 125 but after inclining I got numbers ranging from 112 to 128. I thought both were wrong. I don't desire to get into a fight about this I just thoight my observations might have a wee bit of value re inclining tests. I'm just an old guy who has ben around boats for a long time. Having been through a Pacific Typhoon I'm not sure that the difference in 112 and 128 means a whole lot. Some one should tell the waves.

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Posted 19 February 2011 - 12:58 AM

The electronic inclinometer is not more accurate (only as accurate) than traditional methods in calm conditions, but has some benefits dealing with wind and waves due to averaging.


One more thing ...
If wind and waves are contributing to the heel of the vessel (even slightly) you will get a very accurate measurement of an incorrect heeling moment. Garbage in = garbage out.

#76 Bob Perry

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Posted 19 February 2011 - 01:14 AM

Paul:
Thanks for that. I think that is what I have been saying for years. You just said it better.

#77 Joakim

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Posted 19 February 2011 - 07:20 AM


The electronic inclinometer is not more accurate (only as accurate) than traditional methods in calm conditions, but has some benefits dealing with wind and waves due to averaging.


One more thing ...
If wind and waves are contributing to the heel of the vessel (even slightly) you will get a very accurate measurement of an incorrect heeling moment. Garbage in = garbage out.


In the ORC measurement procedure (I guess ORR has the same) the boat is moored only from the bow, thus it is always bow about to the wind. When using the electronic device four one minute averages are taking of both angles. This will quite accurately cancel out the effect of waves, since there are close to 20 heel cycles in each one minute average. Wind can cause a longer term effect on heel, but that is also quite well canceled out in the four one minute averages, Of course calm conditions should be always selected, but in some areas those are very hard to find.

I just checked one case where the RM was measured four times using water scale and two different electronic devices in a condition where heel varied about one degree (peak to peak) during each one minute measurement (not a very bad condition, but not ideal). The measured RM values were: 175.0, 175.7, 175.0 and 175.6 kgm/deg. And actually there is even a reason for the 0.7 difference, since the two lower values were measured with a bit heavy weights, which resulted in 7.8 degree heel difference and the higher values were measured with 7 degrees heel difference (3.5 degrees to each side) which is within the rule.

Then another one made in really bad conditions. The heel angle varied 3-4 degrees (peak to peak) during each one minute average. Unfortunately for this case there is just one measurement, but the RM calculated from each four pairs of one minute averages varies within +-2%. After averaging these four I think the error is about +-1%. Measuring freeboards is the more difficult part in those conditions.

One big benefit of electronic devices and water levers over pendulum is that the device is not affected by wind when used on the deck, which is the only option for pendulum for smaller vessels.

Around here it is OK to use just one inclining device for boats and small ships. Bigger ships require three. I agree that using 8 shifts (9 different angels) points out the mistakes. It was used earlier also in IMS measurement, but for several years it has been allowed to use one shift only (all the weights from one side to the other).

#78 Joakim

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Posted 19 February 2011 - 09:49 AM

I wasn't trying to say much of anything. Just that in the early days of the Valiant 40's say around 1980 several were inclined and the results were quite varied. I always figured the LPS was about 125 but after inclining I got numbers ranging from 112 to 128. I thought both were wrong. I don't desire to get into a fight about this I just thoight my observations might have a wee bit of value re inclining tests. I'm just an old guy who has ben around boats for a long time. Having been through a Pacific Typhoon I'm not sure that the difference in 112 and 128 means a whole lot. Some one should tell the waves.


Around 1980 I was racing with an Optimist dinghy, thus I don't know much about measurements back then. Did they use the same method as now? IOR did not have the precise hull form, thus calculating AVS could not have been accurate, but of course it should have been about the same for two identical boats.

Do you have a better way to describe the needed stability for sailboats for different races? Or do you think no stability requirement should be applied?

#79 Estar

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Posted 19 February 2011 - 12:57 PM


Just that in the early days of the Valiant 40's say around 1980 several were inclined and the results were quite varied.


Do you have a better way to describe the needed stability for sailboats for different races? Or do you think no stability requirement should be applied?



Two good simple questions.

Again for me there are two separate 'problems' to be solved:

1. The data integrity seems bad - which means the procedure as it is actually carried (not necessarily as it is written) out is bad. Paul suggests there is a an accepted 'ship' standard for inclining procedure that is not being followed by ORR that could solve this problem (if it was actually followed in practice). This is an annoying problem, but for me the less fundamental of the two.

2. The more important is that 'good' boats are being screened out. I have argued to the safety at sea committee that a minimum test for rules/requirements is boats that have safely sailed round the world by Cape Horn and South Georgia, and to both Northern and Southern ice (like Rhodora - a B40), should be deemed (by the rules/requirements) safe enough to sail to Bermuda. That seems straightforward enough. Now why are good boats being screened out? Well first, the screening formula used does not seem to conform to the latest wolfson thinking (nor the obviously successful mini approach) and the 115 value was/is just picked out of the air - the ISO standard seems to be using 100 (for 'normal size' boats) and the minis are not using a degree value (rather a tested kg value at 90 degrees) but also roughly 100. So, there seem to be better alternatives immediately available.

As to whether there should be a stability screening requirement at all- I don't like or support bad complex rules/requirements. So if a better screening test can not be constructed I would prefer a much simpler equally bad rule (like the old RORC SSS number) or no requirement at all (its the skipper's responsibility). But honestly, it seems like we should be able to have a rule today that does a decent enough job.

#80 Cruisin Loser

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Posted 19 February 2011 - 06:08 PM

The standards are based on static righting arm curves of existing boats known to have performed well or poorly from a stability standpoint.

But they've known for a long time that static stability and roll moment of inertia are 2 very different things. Take the mast out of a sailboat and you lower the center of gravity. However, in a dynamic situation, model testing has shown that the mastless boat is far more prone to capsize. To quote from "Desirable and Undesirable Characteristics of Offshore Yachts" (p.61) "..when the models were capsized by wave action, their behavior was controlled by dynamic principles rather than by the static flotation that normally controls a boats attitude."

i once looked into buying an aerodyne 38, but the one i was interested in had an aluminum mast..., not the carbon mast that most of the aerodyne 38"s have.

i never saw the ORC certificate, but Roger Martin told me that the boats with aluminum masts don't meet the Cat 1 requirement without some work - apparently the boats with carbon masts just make it. i guess there is a slight difference in LPS.


Interestingly, the boat with the aluminum mast may actually be more resistant to capsize from wave action, as it will have a higher moment of interia about it's fore-and-aft axis.

I suspect that many older boats which do poorly in the static stability measurements, like the B-40, have heavy tree-trunk aluminum masts, which give them good resistance to snap rolling and may make them far more seaworthy than the static measurements are capable of measuring.

#81 Estar

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Posted 19 February 2011 - 07:52 PM

But they've known for a long time that static stability and roll moment of inertia are 2 very different things. Take the mast out of a sailboat and you lower the center of gravity. However, in a dynamic situation, model testing has shown that the mastless boat is far more prone to capsize.

I suspect that many older boats which do poorly in the static stability measurements, like the B-40, have heavy tree-trunk aluminum masts, which give them good resistance to snap rolling and may make them far more seaworthy than the static measurements are capable of measuring.


Interesting point, which coupled with the observation about deep keels causing 'tripping' does perhaps explain why the Ovni's and B40 are much better sea boats than the static numbers suggests.

Wolfson does have interesting graph showing a very strong correlation between their formula and size of wave needed to capsize (+50) different models in actual tank testing. So, this is empricially derived rather than theoretical. I don't know what sort of 'dynamic factor' it has.

#82 Notmyboatsname

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Posted 03 June 2011 - 05:51 AM


There is a discussing in the mini forum that touched on the ORR stability index. The following link was given for current stability measurements on various current boats: ORR Scratch Sheet

This data looks really really odd to me.

For starters it shows a stability index of 194.5 degrees for the 12 meter Valiant. Seems to be quite a trick of physics to get an index of greater than 180.

Then we have the 330 boats that will not meet the 115 degree minimum . . . some are obvious but some are odd, like a swan 56 (yes a shoal draft version, but still), Tartan 4100 and 37, Passport 40, Bermuda 40, Alden 54, J35, Antrim 49, Hinckley 43, J44 (Njord), Hood 55, Hans Christian 43, Morris 36, and almost all the famous small short handed Hawaii designs like the Olson 30 and moore 24 . . . I have only picked the ones out that I know have quite a successful (safe) offshore passage making history and experience. Some of these individual boats may have had fit out problems - like placing battery banks to high or such, but the long list of well experienced offshore designs suggests some systematic issue.

So, what's the deal here? Is the methodology crap - not actually measuring stability in a way that is relevant to offshore safety, or is the target crap - too high and screening out boats that have excellent offshore records, or are these boats really marginally stable and have just been lucky during their many safe ocean crossings.


The deal here is that those who designed the stability index (proven asinine by the list of DQed boats) have a lack of IQ...simple.

#83 lydia

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Posted 03 June 2011 - 06:35 AM

Everyone take a deep breath, it is an "index"

#84 Polaris

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Posted 01 January 2012 - 04:41 PM

I've personally been involved in four inclines...same boat, remeasures for different gear additions etc. AND have to re-incine this year for a new keel and carbon rig that was added/ changed.

If electric inclining meters are used, you get a significantly more accurate measure, IN MY OPINION.

Also in my opinion, there is a huge X factor of who is doing the inclining...and what technique / tools they have developed for the test. The boat I sail has come in anywhere from 112 to 118 - a pretty big swing...

My last though on it, is that for a bulb keel, the incline test to me is less accurate / telling as well..As the boat is not inclined just a few degrees - may 5 -10 tops...which the data generated is then extrapolated in determining the magic degree of re-righting ability...Not sure if this technique / information gathered really accommodates for the effect of a bulb keel and swinging the bulb off center, where the bulb has greater effects for stiffness.

Maybe Bob / some you more techie types can answer, whether the formula accounts for a bulb OR if his formula is so old, that it assumes a fin/ traditional shape of keel??

Mikie


I have found this interesting with all of the talk of Minimum Stability Index regarding the CYC Mac. On the ORR website, http://offshore.ussa...eward_50_50.htm, finding boats like the J30 and J29 below 100 in the SI number as well as more radical design like the Kiwi 35 and more stable designs like a heavy cruising boat with a shoal keel coming in at the same number of 100. I am thinking that the test needs to be more qualified to include a higher degree of testing rather than 5-10 degrees done now and utilizing of an electronic inclination meter. I would think that AVS would be more important to the race organizers.

#85 us7070

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Posted 01 January 2012 - 04:57 PM


I've personally been involved in four inclines...same boat, remeasures for different gear additions etc. AND have to re-incine this year for a new keel and carbon rig that was added/ changed.

If electric inclining meters are used, you get a significantly more accurate measure, IN MY OPINION.

Also in my opinion, there is a huge X factor of who is doing the inclining...and what technique / tools they have developed for the test. The boat I sail has come in anywhere from 112 to 118 - a pretty big swing...

My last though on it, is that for a bulb keel, the incline test to me is less accurate / telling as well..As the boat is not inclined just a few degrees - may 5 -10 tops...which the data generated is then extrapolated in determining the magic degree of re-righting ability...Not sure if this technique / information gathered really accommodates for the effect of a bulb keel and swinging the bulb off center, where the bulb has greater effects for stiffness.

Maybe Bob / some you more techie types can answer, whether the formula accounts for a bulb OR if his formula is so old, that it assumes a fin/ traditional shape of keel??

Mikie


I have found this interesting with all of the talk of Minimum Stability Index regarding the CYC Mac. On the ORR website, http://offshore.ussa...eward_50_50.htm, finding boats like the J30 and J29 below 100 in the SI number as well as more radical design like the Kiwi 35 and more stable designs like a heavy cruising boat with a shoal keel coming in at the same number of 100. I am thinking that the test needs to be more qualified to include a higher degree of testing rather than 5-10 degrees done now and utilizing of an electronic inclination meter. I would think that AVS would be important to the race organizers as having sailed on boats like the J30, J29, and heavy cruisers, they are very safe boats.



increasing the range of the inclining test won't make a difference.

the inclining test does not directly measure the LPS, rather, it is used to determine the metacentric height.

as far as i know, the current test does this well.

the stability index is not, as many people think, a measure of stiffness, as we commonly think of it - sail area isn't part of the calculation.

it is meant to provide a measure of a boat's resistance to being rolled by a wave.

experiments have shown that, all things being equal, short boats are more likely to be rolled by a given wave, than longer boats.

so, the index penalizes short boats.

i'm not familiar with the J/29, and it may have other issues, but its short length alone is enough to cause an issue with the stability index.

#86 Polaris

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Posted 01 January 2012 - 06:25 PM



I've personally been involved in four inclines...same boat, remeasures for different gear additions etc. AND have to re-incine this year for a new keel and carbon rig that was added/ changed.

If electric inclining meters are used, you get a significantly more accurate measure, IN MY OPINION.

Also in my opinion, there is a huge X factor of who is doing the inclining...and what technique / tools they have developed for the test. The boat I sail has come in anywhere from 112 to 118 - a pretty big swing...

My last though on it, is that for a bulb keel, the incline test to me is less accurate / telling as well..As the boat is not inclined just a few degrees - may 5 -10 tops...which the data generated is then extrapolated in determining the magic degree of re-righting ability...Not sure if this technique / information gathered really accommodates for the effect of a bulb keel and swinging the bulb off center, where the bulb has greater effects for stiffness.

Maybe Bob / some you more techie types can answer, whether the formula accounts for a bulb OR if his formula is so old, that it assumes a fin/ traditional shape of keel??

Mikie


I have found this interesting with all of the talk of Minimum Stability Index regarding the CYC Mac. On the ORR website, http://offshore.ussa...eward_50_50.htm, finding boats like the J30 and J29 below 100 in the SI number as well as more radical design like the Kiwi 35 and more stable designs like a heavy cruising boat with a shoal keel coming in at the same number of 100. I am thinking that the test needs to be more qualified to include a higher degree of testing rather than 5-10 degrees done now and utilizing of an electronic inclination meter. I would think that AVS would be important to the race organizers as having sailed on boats like the J30, J29, and heavy cruisers, they are very safe boats.



increasing the range of the inclining test won't make a difference.

the inclining test does not directly measure the LPS, rather, it is used to determine the metacentric height.

as far as i know, the current test does this well.

the stability index is not, as many people think, a measure of stiffness, as we commonly think of it - sail area isn't part of the calculation.

it is meant to provide a measure of a boat's resistance to being rolled by a wave.

experiments have shown that, all things being equal, short boats are more likely to be rolled by a given wave, than longer boats.

so, the index penalizes short boats.

i'm not familiar with the J/29, and it may have other issues, but its short length alone is enough to cause an issue with the stability index.



• We are in the final determinations of using a minimum stability index (MSI) appropriate to the rating rule for the race (ORR); we will be communicating this MSI in the release of the NOR.
Then why is CYC putting an emphasis on MSI for the 2012 Mac? Straight line wind was problem, not waves.

#87 us7070

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Posted 01 January 2012 - 06:30 PM

i can't speak to CYC's interests...,

but when the stability index was being devised, i doubt they even contemplated the idea of an offshore boat being capsized by wind alone.

#88 Joakim

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Posted 01 January 2012 - 09:40 PM

the stability index is not, as many people think, a measure of stiffness, as we commonly think of it - sail area isn't part of the calculation.

it is meant to provide a measure of a boat's resistance to being rolled by a wave.

experiments have shown that, all things being equal, short boats are more likely to be rolled by a given wave, than longer boats.

so, the index penalizes short boats.

i'm not familiar with the J/29, and it may have other issues, but its short length alone is enough to cause an issue with the stability index.


The stability index comes from LPS + CI + SI.

LPS is the calculated Limit of Positive Stability. It is based on the measured righting moment, hull form and weight. From these the center of gravity and then the whole stability curve can be calculated. However superstructure is not measured and thus not taken into account.

CI is the Capsize Increment, which "measures" the ability of the boat to turn back. It is based on displacement and maximum beam and it can be negative or positive (limited to +-5 degrees, from 2012 only to +5)

SI is the Sixe Increment, which "measures" the size effect on the ability to resists capsizing. It is based on displacement and LWL. It can be negative or positive (limited to +10).

J/29 is small and wide to its displacement. Thus both CI (-7, limited to -5 until 2012) and SI (-1) are negative. Also it has quite low LPS (106) to start with. Thus it may capsize rather easily (by a wave or a wind knock down) and stay capsized.

#89 One eye Jack

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Posted 01 January 2012 - 10:44 PM

Why is it that when some moron buys a boat today and thinks they can sail it around the world tomorrow and disappear that every body just has to make new rules to cover that morons mistakes..Then with these measuring and stability rules...Have we not seen them come and go like IOR, MORC, IMS. Etc..they have come and are no more for a reason..Who wants to sail under them..I don't know about you but I want to feel safe on a boat and have tons of fun and IOR boats were so much fun, that we still design them..NOT...Now let's think of this...these people get all of these rules for a safe ? Boat...and somebody dies..I would sue the holy piss us out of them because they said that such and such boat in their little mind is "safe"...All I will say is screw these rules..If you can't prepare your boat and you and your crew for a race of any kind..then you will get what you get..The crew if they don't like it can all bail on you, help you , or go racing...PHRF has been around for many years for a reason...This is just like when some of us remember when we were younger with the jungle Jim sets at the park or at school. And had saw dust under them...and hen some moron with to many buggers on their fingers slipped and fell off..next thing there was soft rubber on the ground or totally yanked out...But it was only one that ruined it for all..just like sailing...ohhhh we have to be safer...Is that why on an air craft carrier they flat out loose people on every time they go out to sea? Or when a plane goes into the sea from a malfunction ...they don't shut down the mission and make things safer? Or when you get out of bed each morning..The big word here is risk factor...Some people bungee jump..most don't..Or how in the hell did we survive out on these races... Before these idiots come up to make us safer...technology has done that..what's going to be next a boat that can't sink, or hit a crew member in the head from the boom...It used to be called DUCK STUPID!!!..and why is it that these safe boats are having more problems than our Kiiler boats. Like keels falling off...but they are so safe...Now the question is do you want to be safe..they say...Or have fun sailing...and there are those that belong on the water and those that don't belong in a bath tub...all for safety..Is it? Or do they just own a boat that can't win unless they get rules...Just like IOR.. Sorry folks but this suppose to be fun and give us a thrill..Or thats the point..Stay in bed and be safe..But watch out for that meteor that just might fall through your roof...See even you aren't as safe as you think..FUN? Being controlled with safe? Shouldn't it be up to you and not some moron that get hurt chewing gum...

#90 Heriberto

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Posted 02 January 2012 - 01:13 AM



the stability index is not, as many people think, a measure of stiffness, as we commonly think of it - sail area isn't part of the calculation.

it is meant to provide a measure of a boat's resistance to being rolled by a wave.

experiments have shown that, all things being equal, short boats are more likely to be rolled by a given wave, than longer boats.

so, the index penalizes short boats.

i'm not familiar with the J/29, and it may have other issues, but its short length alone is enough to cause an issue with the stability index.


The stability index comes from LPS + CI + SI.

LPS is the calculated Limit of Positive Stability. It is based on the measured righting moment, hull form and weight. From these the center of gravity and then the whole stability curve can be calculated. However superstructure is not measured and thus not taken into account.

CI is the Capsize Increment, which "measures" the ability of the boat to turn back. It is based on displacement and maximum beam and it can be negative or positive (limited to +-5 degrees, from 2012 only to +5)

SI is the Sixe Increment, which "measures" the size effect on the ability to resists capsizing. It is based on displacement and LWL. It can be negative or positive (limited to +10).

J/29 is small and wide to its displacement. Thus both CI (-7, limited to -5 until 2012) and SI (-1) are negative. Also it has quite low LPS (106) to start with. Thus it may capsize rather easily (by a wave or a wind knock down) and stay capsized.


And yet light, beamy 30-footers have successfully sailed and raced long offshore races such as the Transpac and Atlantic crossings without incident for decades. "Rather easily"? more like, "extremely rarely" if history is any judge.

#91 us7070

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Posted 02 January 2012 - 03:36 AM




the stability index is not, as many people think, a measure of stiffness, as we commonly think of it - sail area isn't part of the calculation.

it is meant to provide a measure of a boat's resistance to being rolled by a wave.

experiments have shown that, all things being equal, short boats are more likely to be rolled by a given wave, than longer boats.

so, the index penalizes short boats.

i'm not familiar with the J/29, and it may have other issues, but its short length alone is enough to cause an issue with the stability index.


The stability index comes from LPS + CI + SI.

LPS is the calculated Limit of Positive Stability. It is based on the measured righting moment, hull form and weight. From these the center of gravity and then the whole stability curve can be calculated. However superstructure is not measured and thus not taken into account.

CI is the Capsize Increment, which "measures" the ability of the boat to turn back. It is based on displacement and maximum beam and it can be negative or positive (limited to +-5 degrees, from 2012 only to +5)

SI is the Sixe Increment, which "measures" the size effect on the ability to resists capsizing. It is based on displacement and LWL. It can be negative or positive (limited to +10).

J/29 is small and wide to its displacement. Thus both CI (-7, limited to -5 until 2012) and SI (-1) are negative. Also it has quite low LPS (106) to start with. Thus it may capsize rather easily (by a wave or a wind knock down) and stay capsized.


And yet light, beamy 30-footers have successfully sailed and raced long offshore races such as the Transpac and Atlantic crossings without incident for decades. "Rather easily"? more like, "extremely rarely" if history is any judge.


ok, it seems you are not saying the stability index is inaccurate..., rather, you are saying it's not needed.

but, remember how we got here..., it was the '79 fastnet that prompted the stability investigations that led to this index.

nevertheless, it is certainly true that conditions which can cause a capsize are not commonly encountered by racing yachts.

the index is used so that boats are safe even when unusual conditions occur.

but, it seems to me that you are free to organize a race with whatever stability requirement you want.

#92 Joakim

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Posted 02 January 2012 - 07:50 AM

And yet light, beamy 30-footers have successfully sailed and raced long offshore races such as the Transpac and Atlantic crossings without incident for decades. "Rather easily"? more like, "extremely rarely" if history is any judge.


Have they done that with stability index ~100? Transpac NOR seems to require 115 http://www.transpacr...ocs/NOR2011.pdf

A light and beamy 30-footer can have a good stability index. E.g. Farr/Mumm 30 has over 115. CI and SI just mean that small, light and beamy yachts need to have a higher LPS than heavy, big and narrow ones inorder to be equally safe.

#93 Moonduster

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Posted 02 January 2012 - 10:14 AM

Am I the only one who thinks that this thread misses for forest for the trees? Here's my view ...

First, the only valuable lesson of the '79 Fastnet was that one should not step down into a life raft. Everything else was overkill and the first step into this godforsaken mess that's unrolling before our eyes now.

Second, the new stability measurements do exactly what their designers intended, which is to address the unfortunate fact that fiberglass boats don't rot and they continue to show up and perform too well when compared to brand new designs. It's embarassing for the designers, the handicappers, the mavens of the rules and the people who believe that big money wins races. They've fixed their problem, what are you whining for?

Third, anyone who believes that 30 foot waves are common in 30 knot winds is nuts. Once a week, sure. Common, no. And what does the face of that wave look like? What's it's wave length? I'm guessing about 100 feet and that you can't even feel it slip under the boat.

Fourth, the variation in production boats is legendary. That this causes measurement variation of only a few degrees is the real mystery. Christ, the variation in displacement caused by blisters in the average Valiant 40 is probably worth 2 degrees alone.

Fifth, anyone who believes that sailing around Cape Horn is a good proxy for vessel stability is just isn't paying attention. Take a good look at the first several thousand vessels that rounded Cape Horn. Remember the Pride of Baltimore? There's nothing that's worse for this situation than replacing one arbitrary and incorrect approach with a second arbitrary and incorrect approach.

Finally, there are far, far greater sources of non-seaworthiness than lousy stability. Afterall, how many yachting deaths have been caused by roll overs? Why anyone would focus on this demonstrates the shear insanity of it all. Why not just mandate auto-inflating air bags and be done with it all? Far cheaper, far more effective and far simpler to inspect. Sure, stupid, too ... but not as bizzare as stability measurements.

Why do so many people focus endlessly on the symptom rather than the problem?

#94 One eye Jack

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Posted 03 January 2012 - 12:28 AM

Moon duster: you have pretty well hit it right on..Look what they had to do to Merlin..That was the only way others could beat the boat..these people don't want to come out with radical designs like At that time...Merlin...or any of the other ULDB boats..I think that these people are stuck in the 50's...next will be cotton sails, block and tackle, and sextants...like you stated..Those square riggers made it around the horn many times...and didn't need any formulas like this to do it...Like the little plac says..Oh God my boat is so small and the sea so great...even for an aircraft carrier..What is really safe enough?

#95 Beau.Vrolyk

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Posted 03 January 2012 - 02:29 AM

Moonduster:

+1000 on your post. In the face of a disaster (like Fastnet) very very few people respond in a reasoned and well considered manner. As a result, we end up with numerous stupid "requirements" that are inflicted upon us "for our own protection."

I think we ended up here because of a few basic assumptions that are probably wrong:

1) Assumption: Sailing can be made "safe". This is clearly false, while it can be made "safer" it will never be completely safe and there isn't anyone I've ever sailed with who wants it that way. Sadly, there isn't any consensus on how safe is safe enough. Pushing this along is that Sponsors and large institutions do NOT want people getting killed during their events, bad PR. One can imagine the discussion in the Board Room at Rolex if a headline in the Times of London says something like: "10 killed in Rolex Fastnet Race"

2) Assumption: Sailors will race boats that are dangerous and need to be protected from themselves. This is probably partially true, as plenty of us have raced boats that are clearly less safe than they could be. But the assumption that we need to be protected from ourselves is something that many of us find not only insulting but simply wrong. RRS 4 does a pretty good job of saying who decides if one goes racing, and it is NOT the Organizing Authority or the Sponsor. Rather than eliminate a boat from a race, the OA could simply require the measurement be made (whatever it is) and then have the crew sign a document that says something like: "We understand that the boat we've entered doesn't reach the safety levels recommended by the OA. We indemnify the OA and assume all risk for the decision to race our boat." Of course, that makes one's safety one's own responsibility, and that's something that a lot of Americans don't actually believe in. (Oh gosh, we already agree to this when we enter a race and it says we'll abide by the Racing Rules of Sailing.)

3) Assumption: The Organizing Authority, Race Committee and everyone else involved will be sued by a competitor or their heirs unless an attempt is made to reach state-of-the-art safety regulations. While anyone (especially in the US) can sue anyone for anything, the reality is that there are plenty of dangerous activities in which the folks who run them don't get sued much, and even more in which they don't loose the suits. Personally, I can't recall how many times people have incorrectly told me that there is a liability risk if we do "X" in a race, whatever "X" is. People who are hyper focuses on safety and avoiding litigation use this as a common excuse for not doing much of anything. Considering the risks of skiing, auto racing, rock climbing, sky diving and any number of other activities, sailing seems pretty safe.

Don't assume that I personally don't think we should learn from disasters and use that knowledge to improve boats and sailors. I strongly believe the opposite. However, I do not believe that we should assume that sailors are too stupid or irresponsible to choose a safety level that they individually are happy with. There is a strong argument that once any Authority starts to take over responsibility for safety, buy regulating the constructions and design of things like cars and sailboats, their actions allow and potential encourage individuals to stop thinking about their own safety. This is a sad and unintended consequence of people in authority attempting to do the right thing but doing it in the wrong way.

Here I know I personally disagree with many in the US. I believe that RRS 4 is perfectly adequate and that while various people in positions of authority should do every thing they can to educate sailors on the risks of the race and the boat they sail upon, they should never take responsibility for their safety. Simply put, if a person is allowed to vote, carry a gun and bring children into this world why on Earth aren't they allowed to choose where and what they sail?

BV

#96 TigerinCT

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Posted 03 January 2012 - 03:17 AM

Moonduster:

+1000 on your post. In the face of a disaster (like Fastnet) very very few people respond in a reasoned and well considered manner. As a result, we end up with numerous stupid "requirements" that are inflicted upon us "for our own protection."

I think we ended up here because of a few basic assumptions that are probably wrong:

1) Assumption: Sailing can be made "safe". This is clearly false, while it can be made "safer" it will never be completely safe and there isn't anyone I've ever sailed with who wants it that way. Sadly, there isn't any consensus on how safe is safe enough. Pushing this along is that Sponsors and large institutions do NOT want people getting killed during their events, bad PR. One can imagine the discussion in the Board Room at Rolex if a headline in the Times of London says something like: "10 killed in Rolex Fastnet Race"

2) Assumption: Sailors will race boats that are dangerous and need to be protected from themselves. This is probably partially true, as plenty of us have raced boats that are clearly less safe than they could be. But the assumption that we need to be protected from ourselves is something that many of us find not only insulting but simply wrong. RRS 4 does a pretty good job of saying who decides if one goes racing, and it is NOT the Organizing Authority or the Sponsor. Rather than eliminate a boat from a race, the OA could simply require the measurement be made (whatever it is) and then have the crew sign a document that says something like: "We understand that the boat we've entered doesn't reach the safety levels recommended by the OA. We indemnify the OA and assume all risk for the decision to race our boat." Of course, that makes one's safety one's own responsibility, and that's something that a lot of Americans don't actually believe in. (Oh gosh, we already agree to this when we enter a race and it says we'll abide by the Racing Rules of Sailing.)

3) Assumption: The Organizing Authority, Race Committee and everyone else involved will be sued by a competitor or their heirs unless an attempt is made to reach state-of-the-art safety regulations. While anyone (especially in the US) can sue anyone for anything, the reality is that there are plenty of dangerous activities in which the folks who run them don't get sued much, and even more in which they don't loose the suits. Personally, I can't recall how many times people have incorrectly told me that there is a liability risk if we do "X" in a race, whatever "X" is. People who are hyper focuses on safety and avoiding litigation use this as a common excuse for not doing much of anything. Considering the risks of skiing, auto racing, rock climbing, sky diving and any number of other activities, sailing seems pretty safe.

Don't assume that I personally don't think we should learn from disasters and use that knowledge to improve boats and sailors. I strongly believe the opposite. However, I do not believe that we should assume that sailors are too stupid or irresponsible to choose a safety level that they individually are happy with. There is a strong argument that once any Authority starts to take over responsibility for safety, buy regulating the constructions and design of things like cars and sailboats, their actions allow and potential encourage individuals to stop thinking about their own safety. This is a sad and unintended consequence of people in authority attempting to do the right thing but doing it in the wrong way.

Here I know I personally disagree with many in the US. I believe that RRS 4 is perfectly adequate and that while various people in positions of authority should do every thing they can to educate sailors on the risks of the race and the boat they sail upon, they should never take responsibility for their safety. Simply put, if a person is allowed to vote, carry a gun and bring children into this world why on Earth aren't they allowed to choose where and what they sail?

BV


Nailed it BV, well put.

#97 us7070

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Posted 03 January 2012 - 04:06 AM

really, i don't think you guys understand race organizers...

they are not idiots, and are not simply trying to avoid litigation.

they just don't want people dying in the events they organize.

now, as far as sailors being able to judge the risks themselves, i don't actually see much evidence this is true.

do you really think the wingnuts sailors understood the risks they were taking with that boat?

i tend to think not.

if i recall correctly, two of the sailors were teenagers - do you think they understood?

do you think their parents understood how dangerous that boat was in a squall?

are all crew supposed to become amateur engineers so that they can decide whether to sail on a given boat or not?

it's fine for you to take issue with the validity of a specific safety criterion, but you are opposed to existence of any criteria.

#98 us7070

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Posted 03 January 2012 - 04:24 AM

also, i think you are omitting some of the "lessons" of the 79 fastnet...

everyone remembers the part about stepping up to the liferaft, and that there may have been some unnecessary abandonments.

what you are forgetting..., is that repeated severe knockdowns were explicitly cited as one of the reasons for abandonment!!!!

it turns out it's kind of scary being in a boat that is being rolled, and the people wanted to get out!

so, it's easy to say "step up to the liferaft", but maybe it's hard to do that when you are afraid you are going to be killed by being rolled around in the boat...

#99 dogwatch

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Posted 03 January 2012 - 08:48 AM

'79 Fastnet


AFAIK the current stability requirements came some time later. My first Fastnet was 1993 and there were still ex-half-tonners doing the race at that time through IOR grandfathering provisions. They wouldn't be allowed now.

I don't know about the situation in the USA but in Europe the Recreational Craft Directive stipulates how boats shall be categorised as suitable for various categories of sailing. Although this applies to the sales of boats, not to races, no sane club is going to want to put a race officer into a potential situation where they have to explain to a coroner's inquest why they had disregarded this regulatory framework entirely. It isn't just about the risk of being sued, it's also about protection of the club and its race and safety officers. It's furthermore about sailing keeping its own house in order as far as safety regulation goes lest government decides we need help in the matter. In the UK the Lyme Bay Disaster, where a number of teenagers died in an organised canoeing trip, shows how one high-profile incident can result in far-reaching regulation.

You can argue about how stability indices are calculated and how they are used but to debate whether RRS4 is any longer a sufficient get-out clause for clubs to disavow all responsibility for safety matters is to live in the last century.

#100 Moonduster

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Posted 03 January 2012 - 09:21 AM

US7070,

Way more golfers die from lightening than ever die sailing. Do you think they know the risks? Look, death is inevitable. Safety can't be legislated. There's a generally agreed principle in the RRS about self-determination and the need for personal responsibility. With that as a baseline, the endless cost adders to the sport, especially those that obsolece great designs are just plain dumb.

Your comment about knock downs is interesting ... but the only real lesson necessary is to stay with the damned yacht. There's nothing about improving stability that really mitigates that lesson. And the marginal decrease in roll overs, which really can't even be measured in any meaningful way, will have no material impact on anything other than the price of great boats that can no longer be raced offshore. To think that this is about saving lives is, well, to not really think.

Beau,

Unfortunately, I really believe your naivetee is showing when you say that you feel the various authorities are "trying to do the right thing". There's just no evidence of that whatsoever. What they're doing is the easy thing, and I, for one, believe they know that. That the rules are fundamentally controlled by designers is ridiculous as there's a serious conflict of interest - and always has been. And knee jerk reactions to problems that are statistically insignificant just cannot be defended. When so many smart people do so many seemingly stupid things, one has got to come to grips with the fact that there's something else going on ...

Bottom line, the organizing bodies of our sport are making conscious decisions that cannot be defended on any grounds to disenfranchise a high percentage of the racing community. It's time to throw the bums out!




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