Keel types

[Mattdewizard]

Originally Posted by marcjsmith

why use a thru hull knot meter. just use GPS.



you will need holes in the boat for drains for sink, heads, bilge, water intakes for engine cooling. Possible holes for hvac cooling... unless you do some sort of a "sea chest" type arrangement to minimize holes...

GPS does not give depth soundings or temp. readings like those units do.

[Mattdewizard]

With a diesel heater and thermal heat transfer through the hull I think I could do HVAC without sea water.

[Mattdewizard]

I think I can do HVAC with a diesel heater and thermal heat transfer through the hull.

[marcjsmith]

You could go with an ultrasonic speed sensor. No moving parts, and they can be transom mounted.....

[cal40john]

Originally Posted by Mattdewizard

I'm interested in the Enduro 54. Does anyone have any advice on a wide beam monohull with a bustle(very shallow draft long keel) with a centerboard for world cruising. It has an avl of 120, stability index of 52, and a capsize ratio of 1.94.

I'm not familiar with bustle relating to a shallow draft keel. The bustle I'm familiar with is a weird bump in the hull near the rudder to enhance your rating in 12 meter and IOR designs.

https://i.pinimg.com/originals/f5/e0...629296ea11.jpg

[TrentePieds]

Matt:

Are you sure you are up to handling an Enduro54 (as projected) at this stage of your development as a seafaring man? Handling such a vessel is NOTHING like blowing a "motorhome" or a RAM350 P/U down Route 66!

I think you would do yourself an enormous favour if you were to read:

Arthur Beiser, The Proper Yacht

This book is a wonderful discourse on what a PROPER yacht IS and SHOULD BE by a man who has many, many ocean miles under his belt. Interspersed in the discourse are specific discussions of many ocean-going yachts right from the diminutive 29-footer Lene by the renowned Danish designer, Utzon, on up in length to Beiser's own fabulous 59-foot steel-built ketch Minot's Light, a design by the much-respected American designer John Alden. She was built by the justly famous Abeking & Rasmussen yard in Germany.

Francis Kinney: Skene's Elements of Yacht Design

This book was used for many years as the text for introductory courses in yacht design. Note that "Naval Architecture" is a very different thing! Elements will give you a glimmer of understanding of how a yacht is designed, and why it is so designed. After you have read the book, you may want to revisit some of the comments you have made in this forum.

Both books are available on Amazon. Both books are a little long in the tooth by now, but you will never understand MODERN designs like the Enduro unless you know "where we've come from". The sea in unchanging, and modernity and fashion are rightly suspected by those who roll the dice with Poseidon!

TrentePieds

[MicHughV]

Skene's Elements of yacht design book was my bible back when I was building my boat in the late 70's.
It's a marvelous book.
I agree, a 54 footer is a very big, big boat, and expensive too, even if money is no object
Lotsa upkeep and maintenance.

[Bowdrie]

Originally Posted by MicHughV

I agree, a 54 footer is a very big, big boat, and expensive too, even if money is no object
Lotsa upkeep and maintenance.

Yeah, from the website and the OPs desires, I would expect that boat to be pushing towards the $1.5M range, and then the toys and outfitting might easily add another 10>15%.
A rig that reaches the sky.
Something a bit more conservative on a lower-slung ketch rig that can be MUCH more easily handled by a short-handed and tired crew.
I'm still suspect of that capsize ratio.

[skipperpete]

Well, the Swan 80 has a 12 tonne lifting keel and a draft of 4.2 meters for normal work. I saw one that took the ground and THE REPAIR was alleged to have been over €1 million. The Swan team were flown in and they cut out and replaced the keelbox.... a carbon fibre masterpiece accurate to .010”. It was not a swing keel, just a vertical aero foil fin in a tight case and only useful for docking where marina depth is limited.
The weirdest keel I’ve seen is the blade and bob weight style, I saw an open 60 in the slings on its way to its custom made cradle and that keel was flopping Port and starboard as the lifter progressed across the yard. Ideal design for collecting nets and trawl lines.

[wingssail]

The thing that strikes me is that this is a pretty big boat for a swing keel (and a pretty big boat for single handing).

And other than that itty bitty bustle/keel there is no place for ballast except the centerboard and internal. That centerboard will be highly stressed to provide the stability you claim to want.

So you would be considering a brand new design with an "Interesting" ballast placement.

Thats: "big boat", "new design", "experimental" and a few other rather strange requirements. If this is what you want, go for it, but I'd recommend caution.

[Mattdewizard]

Originally Posted by marcjsmith

You could go with an ultrasonic speed sensor. No moving parts, and they can be transom mounted.....

Ultrasonic speed sensor. Thanks.

[Mattdewizard]

Thanks for the comments and suggested reading material. After looking at some stability diagrams an avs of 120 is quite low and a capsize ratio of 1.94 no better. Enduro54 is going to deep space alone if it can't be majorly redesigned. However the concept of a long shallow keel with centerboard is highly regarded for expedition boats. Take a look at the Pelagic series designed by Tony Castro. As for my seamanship abilities I plan on taking many courses.

[Joli]

Originally Posted by marcjsmith

why use a thru hull knot meter. just use GPS.



you will need holes in the boat for drains for sink, heads, bilge, water intakes for engine cooling. Possible holes for hvac cooling... unless you do some sort of a "sea chest" type arrangement to minimize holes...

You need the paddle wheel to calculate true wind speed and angle.

[TrentePieds]

In reply to Matt's #27: "Enduro54 is going to deep space alone if it can't be majorly redesigned."

Hm... isn't that a rather rash statement by a seafaring novice upon a professional yacht designer's work?

Perhaps, Matt, you would tell us in what circumstances a novice - as you confess to being - would EVER find himself in a boat that has heeled to anywhere near the AVS.

You might also tell us what happens to sailboats that DO get rolled to that angle of heel, and just to ensure that we have the basic principles quite clear, what would be the range of "heeling angles" beyond the AVS for a boat with an AVS of, say 130º before the righting moment of the "inverted" boat again becomes zero?

Give us a little discourse on how the AVS is affected by changes in beam. Will, ceteris paribus, a boat with less beam than another have a greater or a smaller AVS?

And the capsize ratio: What is it good for? What do yacht designers use it for? How is it calculated? Of what use is it to a novice?

Back to the books, eh :-)?


All the best

TrentePieds

[Mattdewizard]

Ok TrentePleds. I'm up to the challenge your questions demand. Calculating capsize ratio... Displacement/64. Then take cube root. Finally divide that by the beam. All I know is that the farther under 2 the better. Perhaps you can explain further what it is good for. Yes. I did make a rash statement upon a professional yacht designers work. Why settle for mediocre when you can get better. In my novice opinion this is an explorer boat on a race hull. If capsized with a minimalist avs of 120, say 130 with tanks filled, etc. It could take 30% of the energy first used to capsize it to right it. I don't precisely what circumstances would produce a roll anywhere near 120. Perhaps a weather forecasting blunder when rounding Cape horn. An unexpected wind shift against a strong current producing breaking confused seas. Tell me this, under what circumstances do you want to hear your wife and children in a panic because you could have chosen a better boat? A boat with less beam, all other things being equal, will have a greater avs and less form stability. I.e. will carry less sail. I'll get back to you on the question of when a boat with an avs of 130 in the inverted position has a righting moment of zero.