Is a Catalina 22 Seaworthy Enough to Make the Passage from Florida to the Bahamas ?

[JK n Smitty]

I do love it when people get overly involved in math instead of actually seeing and feeling how a boat sails for the given purpose.

Ever read what Ted Brewer said about comfort ratio (a numerical measure he invented):

This is a ratio that I dreamed up, tongue-in-cheek, as a measure of motion comfort but it has been widely accepted and, indeed, does provide a reasonable comparison between yachts of similar type.

In other words, you can't compare a comfort ratio from a C22 to that of a Valiant 40. But we see people do it all the time.

[davidlaing]

Originally Posted by boatman61

I'm not.. nor ever have been a racer.. but I do know that they are built for that specific purpose with wafer thin hulls extra wide beams and juggled ballast.. they were and are disposable as far as the sponsors are concerned.. and my take on it is these boats were not designed/built to meet the handicap but to cheat it..
They were specialist boats built for a specific purpose.. whereas something like a Westerly GK 29 and 34 were cruisers racers that competed under the IOR rules but were a totally different animal.. weight was in the keel not the bilges with just an iron fin..

I'll be honest.. I've never read Marchaj.. or any other treatise on seaworthiness.. never been big on theory.. just take what I've got and use it as best I can...
What's the rating you'd give a 1969 Hurley 22.. seaworthy enough for 50kts plus and 10metre sea's in the Biscay..??
I say yes.. your numbers would say no..

Not a bad little boat, actually. D/LWL = 354 (heavy cruiser); SA/D = 12.92 (undercanvassed); CSF = 1.84 (moderately seaworthy); MCR = 23.1 (moderately comfortable); SI = 12.6 (coastal cruiser, about the same as a Catalina 30); Ba/D = 0.59 (stiff; heavily ballasted). I'd much rather be in one of those than a Cat 22 under the conditions you specified!

[ben373]

I have seen one of these boats capsize in Sydney harbor following a southerly buster of 50 knots. We were in a race and the huge wind change came upon us without warning. The Catalina 22 had full sail and a number 1 headsail. It rounded up wildly the crew were thrown to the side and the boat turned turtle and did not right itself. This was a fixed keel boat but shallow draft I think. The large cockpit and wide beam were not helpful.

These were enclosed waters that is no waves. There was some bad seamanship here but three many other boats in the same predicament. I would not leave the harbour in a Catalina 22.

Sent from my Nexus 4 using Cruisers Sailing Forum mobile app

[davidlaing]

Originally Posted by sailorboy1

Is all this STUFF really necessary in order to talk about whether a Catalina 22 can go Caribbean island hopping?

Marchaj and Rousmaniere thought it was, and I happen to agree with them, which is why I wrote my book. No, it's not NECESSARY, but I do think it's USEFUL because it has predictive value. Yes, it is rough and dirty, but it is able to tell you a lot about WHY a Hurley 22 is a far better choice for crossing the Florida Straits in 25 kts of wind from the east than a Cat 22.

[DoubleWhisky]

Originally Posted by goat

I was actually referring to davidlaing's newly discovered seaworthy number;

In the course of writing my soon-to-be-published book Seaworthy Sailboats, I developed a new Seaworthiness Index (SI), which is simply the MCR divided by the CSF. My friend Ted Brewer, who has designed many fine, seaworthy sailboats, has tested my SI on a wide variety of boats and he tells me that he would not be happy going offshore in a boat with a lower SI than 15.0. The SI of the C22-2, at 4.1, is very low.That of the Cat 30 is better at 12.4.

Oh yes...

SI abbreviation normally stand for Stability Index - the old formula, used (in one of variations) in International Measurement System (IMS)

This is the reason for naming newer formula STIX - for STability IndeX, not to confuse with the old one.

The real problem with davidlaing's invention is, that his formula does not include any of data important for stability calculations, like ballast to displacement ratio, angle of vanishing stability, righting moment, righting arm and so on, neither the measurements for any approximate calculations like depth of the hull, depth of the ballast or breadth of waterline, metacentric height aside. Without those this formula can be of some use when comparing similar boats, but probably for nothing more - just like the Motion Comfort Ratio (according to its inventor, Mr Brewer).

[davidlaing]

Originally Posted by JK n Smitty

I do love it when people get overly involved in math instead of actually seeing and feeling how a boat sails for the given purpose.

Ever read what Ted Brewer said about comfort ratio (a numerical measure he invented):

This is a ratio that I dreamed up, tongue-in-cheek, as a measure of motion comfort but it has been widely accepted and, indeed, does provide a reasonable comparison between yachts of similar type.

In other words, you can't compare a comfort ratio from a C22 to that of a Valiant 40. But we see people do it all the time.

It's easy to dismiss something when you don't understand it. Let me help you (from my book):

Ted Brewer's motion comfort ratio (MCR), which he confesses he developed 'tongue-in-cheek,' has also gained wide respect among sailors. The MCR, as its name suggests, is a measure of how well a boat resists being tossed about like a cork in a boisterous seaway. The formula1 is:

MCR = D/(.65(.7LWL+.3LOA)Bm4/3).

Here, displacement, in the numerator, acts as a damping factor, resisting the wave forces that are trying to toss the boat around, whereas the waterplane area and the beam, in the denominator, present a surface and a lever arm, respectively, on which those forces can act. Higher MCR values therefore indicate more sedate and seakindly boats, while lower ones indicate livelier ones that are more likely to challenge the unhardy stomach.

[davidlaing]

Originally Posted by DoubleWhisky

Oh yes...

SI abbreviation normally stand for Stability Index - the old formula, used (in one of variations) in International Measurement System (IMS)

This is the reason for naming newer formula STIX - for STability IndeX, not to confuse with the old one.

The real problem with davidlaing's invention is, that his formula does not include any of data important for stability calculations, like ballast to displacement ratio, angle of vanishing stability, righting moment, righting arm and so on, neither the measurements for any approximate calculations like depth of the hull, depth of the ballast or breadth of waterline, metacentric height aside. Without those this formula can be of some use when comparing similar boats, but probably for nothing more - just like the Motion Comfort Ratio (according to its inventor, Mr Brewer).

Thank you! Nice to get an intelligent comment for a change. You're absolutely right about the limitations of my SI, which I fully acknowledge in my book. I make no claim to originality, by the way, other than the realization that MCR/CSF could be used as an index to characterize a boat's expected behavior in a seaway with respect to capsize resistance, righting ability, and response to accelerating forces. From the book:

<my seaworthiness index SI is simply the MCR divided by the CSF. In dividing the one by the other, I am essentially 'normalizing' them, that is, expressing the one relative to the other. The resulting value can be seen either as 'the variation in capsizability of boats of a given comfort level,' or, conversely, 'the variation in comfort level of boats of a given capsizability.' This gives a convenient, combined index of overall seaworthiness in which a deficiency in one factor can be compensated by a surfeit in the other. High resistance to capsize, for example, will compensate for the tendency of a lively boat to be tossed about in a seaway. Conversely, steadiness in a seaway will compensate for low resistance to capsize because a steadier, more seakindly boat will be less likely to be thrown into a position from which she can be capsized. At my request, Ted Brewer kindly reviewed the SI for me, and after applying it to several boats with whose performance characteristics he is familiar, including some of his own design, he concluded that an SI value of 15.0 is about right for separating offshore-capable boats from coastal cruisers. Accordingly, I have used that value as one of my selection criteria, eliminating all boats having an SI below 15.0.>

Thanks, BTW, for pointing out the conflict with the earlier use of 'SI.' I need to address that, and will do so before publication.

[DoubleWhisky]

Originally Posted by davidlaing

At my request, Ted Brewer kindly reviewed the SI for me, and after applying it to several boats with whose performance characteristics he is familiar, including some of his own design, he concluded that an SI value of 15.0 is about right for separating offshore-capable boats from coastal cruisers.

Just curious...
What number is adequate - in Your opinion - for really seaworthy blue water cruiser.
I just made some calculations for known to me (bigger) boats, and came to the bracket of 22 - 26, but may be it is not proper answer...

[boatman61]

[QUOTE=davidlaing;1464962]Thank you! Nice to get an intelligent comment for a change. QUOTE]

Right.. that's it.. I'm gonna sit in the corner and Sulk...

[Coops]

You just don't agree with his views Boatie, therefore your comments cannot be intelligent. That's how I read a lot of folks posts, on many different subjects, and it is a poor slant on debating a subject to me. If you disagree with that by the way, you are stupid.

Coops.

[davidlaing]

Originally Posted by DoubleWhisky

Just curious...
What number is adequate - in Your opinion - for really seaworthy blue water cruiser.
I just made some calculations for known to me (bigger) boats, and came to the bracket of 22 - 26, but may be it is not proper answer...

Any answer I could give you would be subjective. It all depends on the usage for which the boat is intended and the boldness of her skipper. On Ted Brewer's advice, I used 15.0 as a good, but arbitrary, divider between coastal cruisers and bluewater cruisers. The Bristol 30 (15.0) and the Pearson 424 (15.5) come in at the low end, and I probably wouldn't try Cape Horn or the Bass Strait in either one, but I might do so in a Sunward 48 (32.9) or a Formosa 51 (36.3).

[JK n Smitty]

Originally Posted by davidlaing

Thank you! Nice to get an intelligent comment for a change. You're absolutely right about the limitations of my SI, which I fully acknowledge in my book. I make no claim to originality, by the way, other than the realization that MCR/CSF could be used as an index to characterize a boat's expected behavior in a seaway with respect to capsize resistance, righting ability, and response to accelerating forces. From the book:



<my seaworthiness index SI.....

First, I believe you should check the forum rules. Pretty sure if you are going to pimp your product this hard you are not following the rules for commercial forum participants. Also, thread high jacking man.

Second, why do you have to answer posts like such a d@$k?

[davidlaing]

Originally Posted by JK n Smitty

First, I believe you should check the forum rules. Pretty sure if you are going to pimp your product this hard you are not following the rules for commercial forum participants. Also, thread high jacking man.

Second, why do you have to answer posts like such a d@$k?

Look who's talking!

[sailorboy1]

Originally Posted by JK n Smitty

First, I believe you should check the forum rules. Pretty sure if you are going to pimp your product this hard you are not following the rules for commercial forum participants. Also, thread high jacking man.

I second this. If you want to pimp your book start a thread for it!

[JK n Smitty]

Originally Posted by davidlaing

Look who's talking!

You've made 18 posts since joining in 2009, most of them on this thread. In 9 of the 18 you mention your book. You have no profile info filled out and only like 6 posts before you started high jacking this thread. Give it a rest already. If your book is any good you don't have to pimp it this hard.

Back to the OPs question, plenty have done that crossing in C22's or similar boats. Your skills and the condition of your boat will be more important. Put your efforts there.

Good luck and fair winds,

Jesse