Hull shape how aware are you ?

[Portofino]

I ve noticed a lot threads where the answers to questions that arise are all in the hull shape .

I have even started saying stuff like --" why do exhibitors at boat shows fit skirts around the hull "
Nobody seems to pick me up on that ?

For me that's the 1st place I want to look at ,not the flat floor or not in the saloon , no of steps into the Midcabin , size of dishwasher , no of screens on the dash , Type of underwater light ,which spin stab ?

Rant over
Enjoy --
http://www.boats.com/boat-buyers-guide/what-hull-shape-is-best/

 

[Seastoke]

I ve noticed a lot threads where the answers to questions that arise are all in the hull shape .

I have even started saying stuff like --" why do exhibitors at boat shows fit skirts around the hull "
Nobody seems to pick me up on that ?

For me that's the 1st place I want to look at ,not the flat floor or not in the saloon , no of steps into the Midcabin , size of dishwasher , no of screens on the dash , Type of underwater light ,which spin stab ?

Rant over
Enjoy --
http://www.boats.com/boat-buyers-guide/what-hull-shape-is-best/

i look but dont under stand what makes a great sea keeping but assume the designer knows

 

[paul salliss]

I like this thread.

It irritates me when people bang on about interior stuff like it really matters. Hull shape, quality of build, range , stuff like that is what counts.

 

[Bouba]

I start with the engine, if it's on my (very) short list of reliable power plants then I can get interested in the boat. My list grows as the number of engine grows, i.e. Reliability is unimportant if you have four engines as you have so much inbuilt redundancy
Ps. Let's be honest pounds per mètre is very important to me, good value is paramount

 

[rbcoomer]

i look but dont under stand what makes a great sea keeping but assume the designer knows

Bit of an assumption! I think it's more about compromise where builders are concerned - if the market demands beamy hulls with lots of internal space, then that's what they'll make. Might cost a few knots, but many boats are floating holiday homes anyway and only go a few miles to nearest beach/cove, so perhaps a worthy trade off. Then at the other end, the American lake boats with flat bottoms built for speed, but throw in a bit of chop and you get wet - or a broken spine - or both!

 

[Seastoke]

Bit of an assumption! I think it's more about compromise where builders are concerned - if the market demands beamy hulls with lots of internal space, then that's what they'll make. Might cost a few knots, but many boats are floating holiday homes anyway and only go a few miles to nearest beach/cove, so perhaps a worthy trade off. Then at the other end, the American lake boats with flat bottoms built for speed, but throw in a bit of chop and you get wet - or a broken spine - or both!

i agree but can you tell by looking at the hull ,i assume the sea trial is best ,looking at deep vee tells me its not bad but what ekse tells peeps its good

 

[MapisM]

I like this thread.

It irritates me when people bang on about interior stuff like it really matters. Hull shape, quality of build, range , stuff like that is what counts.

Geez... If you get irritated every time someone thinks that what really matters is different from whatever you believe is important, I don't dare thinking how much you must spend on tranquilizers...

I also would like this thread in principle, if it weren't that the debate is bound to be either trivial (to the point of being completely useless), or so technical to require a naval architect competence to understand it - not to mention contribute in a meaningful way!
For starters, I'm afraid that the article linked by Porto falls entirely in the trivial/useless field - the most interesting thing being the nice pic of the Frauscher hull.

Let's face it, folks. The reason why most boaters couldn't care less about the ultimate seakeeping hull is that their priorities are different, and that's perfectly legitimate.
For all its faults, the boating industry understood that very well, and the trend towards hulls designed around interior spaces (as opposed to hull first, the rest follows) is just a logical, demand-driven consequence, whether all of us like it or not...

 

[Bouba]

It's quite surprising to me at least, how often I read of people rejecting a boat because the cabinetry is the wrong shade of wood. Also how good cabinetry is taken as a sign that the whole boat is quality. The same seems to be true with motor homes.

 

[rbcoomer]

Geez... If you get irritated every time someone thinks that what really matters is different from whatever you believe is important, I don't dare thinking how much you must spend on tranquilizers...

I also would like this thread in principle, if it weren't that the debate is bound to be either trivial (to the point of being completely useless), or so technical to require a naval architect competence to understand it - not to mention contribute in a meaningful way!
For starters, I'm afraid that the article linked by Porto falls entirely in the trivial/useless field - the most interesting thing being the nice pic of the Frauscher hull.

Let's face it, folks. The reason why most boaters couldn't care less about the ultimate seakeeping hull is that their priorities are different, and that's perfectly legitimate.
For all its faults, the boating industry understood that very well, and the trend towards hulls designed around interior spaces (as opposed to hull first, the rest follows) is just a logical, demand-driven consequence, whether all of us like it or not...

Those of us who don't, look for classic hulls by reputation, recognised builder etc!

Quite a few around this part of the world don't seem to leave port if it's anything more than a breeze so hull capability is perhaps immaterial. By contrast, the racing world seem make some great hulls, but not sure they'd cut it in the floating apartment sector

 

[Portofino]

Geez... If you get irritated every time someone thinks that what really matters is different from whatever you believe is important, I don't dare thinking how much you must spend on tranquilizers...

I also would like this thread in principle, if it weren't that the debate is bound to be either trivial (to the point of being completely useless), or so technical to require a naval architect competence to understand it - not to mention contribute in a meaningful way!
For starters, I'm afraid that the article linked by Porto falls entirely in the trivial/useless field - the most interesting thing being the nice pic of the Frauscher hull.

Let's face it, folks. The reason why most boaters couldn't care less about the ultimate seakeeping hull is that their priorities are different, and that's perfectly legitimate.
For all its faults, the boating industry understood that very well, and the trend towards hulls designed around interior spaces (as opposed to hull first, the rest follows) is just a logical, demand-driven consequence, whether all of us like it or not...

Bit Harsh
I think the link does not trivialise the subject at all ,it was carefully chosen for ease of understanding .
Hull form is not as trivial as underwater lights or the colours of the cabinetry
Far from useless to i suspect the majority of MoBo owners .If its pitched too high then we have lost folks .

I think MoBo ers DO care about seakeeping it's just I suspect they don,t know why the boat behaves in a certain way and want to know why ---see post # 6 .

Yup the lets call it the marketing bandwagon @ boat shows skims over ( no pun intentered ) the hull form ,it's that marketing and consumer desire for the floating appartment side of the product and the perception by the punter of how they will use the boat .
Seakeeping I think is still a strong enough priority in some brands ,take Boston Whaler for example

I,am a great believer in "put up or shut up " -- while its Allways interesting to hear /read all posts - MapishM any chance of adding something a bit more useful , than frank criticism ie "put something up " in an easy understandable format .

Helm it a little ,apply a little rudder if you think we are off in the wrong direction .Don,t be the first like Cap Scilarchi ( sp?) to jump off

 

[MapisM]

Don,t be the first like Cap Scilarchi ( sp?) to jump off

Mmm... I suppose it's Schettino you are referring to. If so, is it my previous comment that was a bit harsh? :ambivalence:

No worries anyhow, I'll tell you what.
If you really choose the article carefully, and you are convinced that it does not trivialise the subject at all, can you explain me what sort of conclusion someone with zero experience/knowledge of the subject can draw from it, because I honestly can't think of any?
Maybe aside from preferring a deep-vee Magnum Bestia to a Sealine T50 if wave jumping at speed is your thing, or choose a skiboat if you prefer waterski instead.
Not exactly breaking news, or is it?

And article aside, you told in your OP that the first thing you want to look at is the hull.
Now, let's forget the Magnum vs. Sealine example, for which common sense alone is sufficient to tell which is designed for what, just at first glance.
Let's consider similar boats instead, like a Princess and a Fairline flybridge, or an Itama and a Baia open boats, all of comparable size.
Are you saying that you can tell which is the best in this couple of comparisons just looking at the respective hulls?
I for one sure couldn't (also after having read that article...! ), and I very much doubt that even a naval architect could.

What I'm trying to say is that the idea of looking at hulls, meant as "evaluating" them, is nice in theory but impossible in practice.
You said not long ago that you were not impressed after seatrialing a Rivale, because she slammed much more than your Itama.
Which is fine, and I fully accept it, because you said that after a seatrial.
But if you could have understood that beforehand, after reading the above article or looking at the Rivale hull, why waste your time further with a seatrial...?

 

[paul salliss]

It's quite surprising to me at least, how often I read of people rejecting a boat because the cabinetry is the wrong shade of wood. Also how good cabinetry is taken as a sign that the whole boat is quality. The same seems to be true with motor homes.

I know of a guy who flogged a Fairline and replaced it with a similar sized Princess, age difference was two years. He much prefers the high gloss wood in the Princess but reckons the Fairline was a slightly better sea boat. True story, he really wanted that shiny wood! I suppose it his money so he can do what he wants

 

[MYAG]

I'm with MapisM in all this Porto. I don't understand what your point is here or what you are trying to compare... I mean you don't go out in anything more than a chop or a breeze, you've said so yourself before, and when you do go out its up and down your local coastline a few miles so why is hull form at the top of your order of importance and what do you understand from it, apart from what the article tells you?

 

[PowerYachtBlog]

By looking at hulls nowadays (myself) I can have a very close idea (95% i get it right) what one would do, but think of me as being a bit crazy on the subject.
I used to sneak into boat yards at 8 years old to see boats on the dry and after many years (today I am 41) you start to get what do and does.

But in time I also learned that however a nice V can be that alone does not cut it and weight distribution place another part.

Obviously the Itama and in similar fashion the Magnum (even more) the hull is the center of attraction to what happens and where the master stateroom will be placed.
Today many boat builders (specially those you see publicized in magazines) do it the other way round with the owners room being the protagonist followed by a sleek shape.
It works this way stateroom for Mrs exterior shape for the Mr.

But it is not so black and white there is a lot of grey in middle. Meaning that the boat with the big midships stateroom can still be okay in rough seas albeit at a slower mid 10s knots speed versus the 25 you will be doing with your Itama.

I also think if you consider hull geometry correct weight distribution of high importance the current cruiser yacht market (90%) does not cut it, so then you have to look at Sportfishman (which are toys for boys) or classic inspired designs (lobster boats etc).

 

[Portofino]

Mmm... I suppose it's Schettino you are referring to. If so, is it my previous comment that was a bit harsh? :ambivalence:

No worries anyhow, I'll tell you what.
If you really choose the article carefully, and you are convinced that it does not trivialise the subject at all, can you explain me what sort of conclusion someone with zero experience/knowledge of the subject can draw from it, because I honestly can't think of any?
Maybe aside from preferring a deep-vee Magnum Bestia to a Sealine T50 if wave jumping at speed is your thing, or choose a skiboat if you prefer waterski instead.
Not exactly breaking news, or is it?

And article aside, you told in your OP that the first thing you want to look at is the hull.
Now, let's forget the Magnum vs. Sealine example, for which common sense alone is sufficient to tell which is designed for what, just at first glance.
Let's consider similar boats instead, like a Princess and a Fairline flybridge, or an Itama and a Baia open boats, all of comparable size.
Are you saying that you can tell which is the best in this couple of comparisons just looking at the respective hulls?
I for one sure couldn't (also after having read that article...! ), and I very much doubt that even a naval architect could.

What I'm trying to say is that the idea of looking at hulls, meant as "evaluating" them, is nice in theory but impossible in practice.
You said not long ago that you were not impressed after seatrialing a Rivale, because she slammed much more than your Itama.
Which is fine, and I fully accept it, because you said that after a seatrial.
But if you could have understood that beforehand, after reading the above article or looking at the Rivale hull, why waste your time further with a seatrial...?

I think the opening narrative is the main conclusion

"Whether your boat has a large engine or a small one, one bunk or a dozen cabins, a gourmet galley or a one-burner stove, there is nothing — absolutely nothing — that will make as much difference to your boating pleasure as the design of your hull."

Reading this forum just wondered ,sensed the impression this "design of the hull " stuff has somehow got lost these days .
It's not about ranking or comparing as the article infers there's no perfect shape ,depends what you want from the boat ,how you mostly plan to use it ,
Just wonder bit like golf if people know here's different shaped clubs for different job,s and with boats why the hull shape seems to be low down in the pecking order ,

I,am not saying just by looking under the skirt ( if the hull is covered -boat dressed up at an indoor show ) I can tell which is as you say is "best " - depends what you what to do with it .
If it ,s rough weather performance ,anti slamming ,smoother ride and so on ,which I suspect you are referring to ?
It would be helpful to glean some idea to save wasting time as I did with the recent Rivale debarcle .
I had witnessed a 44 slicing through wave previously and crucially seen some out of the water @ dealers .
Saw a deep V ,high deadrise , low shaft angle ,small rudders ,fine entry ,not too beamy ,no flat slamming sections to speak of .
So I could see ,or I thought it was pretty obvious ( without naval artictects experiance ) that hull form was the answer .

Next boat show I pre-arranged a demo on a Rivala 52 .I did not ,and still have not seen the underwater hull shape .Boat was in .
You can see /feel the beam that's all in the water ,wow what a disapointment ,real disapointment .
Slammed in nothing sea ,bang ,crash ,wallop etc had to slow down to 22-25 knots

That's the point -if only there was a way ,a prognostic or series of prognostic indicators to give some idea .
We wasted a day . Compete waste of time ,
Fortunately at least I had a sea trail easly laid on no strings ,deposits etc -walked away .

Arranging multiple a sea trail could be a time consuming affair ,so it would be nice to somehow be able to shorten that list

Think of it of test driving a car ,without a degree in Mech eng ,you can make a short list just by looking ,as the article ,says a Rolls Royce looks different to a off roader etc ,ground clearance ,chunky tyres etc .

Back to boats ,above water ,theres the bow area ,some like Cap Camerats ,Jeaneau ,Bertram,s have a Caroliner flair .Concave - they ride dry ,deflect the water away from the occupants .I have seen that .
Others have what appears an inflated almost bubble sides /bow ,kinda convex ,they spray water at the occupants ,wet ride .

So there's an example of eying up hull form before,go any further .

Flat ish stern sections with a fuller ,less sharper bow ,oversized trim tabs ( compared with similiar size ) are just a few examples of hull evaluation .
That I would tend to walk away from -save wasting time ,there 100 ,s out there .
In other words we wouldn,t get to see the colour of the cabinetry , how flat the saloon floor is ,or write down my details ,fight with the "gate keeper ", wait for my "personsal assistant " or receive junk e-mail etc

 

[Portofino]

I'm with MapisM in all this Porto. I don't understand what your point is here or what you are trying to compare... I mean you don't go out in anything more than a chop or a breeze, you've said so yourself before, and when you do go out its up and down your local coastline a few miles so why is hull form at the top of your order of importance and what do you understand from it, apart from what the article tells you?

This not about comparing and it not about (or I hope people jump to the wrong conclusion ) about my current boat or perceived usage .
It's about as the post title i hope infers raising awareness of hull shape .

Is there any aspect of the authors opening sentence you particulary disagree with ?

"Whether your boat has a large engine or a small one, one bunk or a dozen cabins, a gourmet galley or a one-burner stove, there is nothing — absolutely nothing — that will make as much difference to your boating pleasure as the design of your hull."

I know you have a very nice large boat by forum standards ,suspect it's not got a "one burner stove "
From the other end of the specrum can you identify with the above sentence in any way ?--

 

[Portofino]

By looking at hulls nowadays (myself) I can have a very close idea (95% i get it right) what one would do, but think of me as being a bit crazy on the subject.
I used to sneak into boat yards at 8 years old to see boats on the dry and after many years (today I am 41) you start to get what do and does.

But in time I also learned that however a nice V can be that alone does not cut it and weight distribution place another part.

Obviously the Itama and in similar fashion the Magnum (even more) the hull is the center of attraction to what happens and where the master stateroom will be placed.
Today many boat builders (specially those you see publicized in magazines) do it the other way round with the owners room being the protagonist followed by a sleek shape.
It works this way stateroom for Mrs exterior shape for the Mr.

But it is not so black and white there is a lot of grey in middle. Meaning that the boat with the big midships stateroom can still be okay in rough seas albeit at a slower mid 10s knots speed versus the 25 you will be doing with your Itama.

I also think if you consider hull geometry correct weight distribution of high importance the current cruiser yacht market (90%) does not cut it, so then you have to look at Sportfishman (which are toys for boys) or classic inspired designs (lobster boats etc).

Thx W
Something educating .
I started ship yard walking later in life about 10 y ago .
Trying to reconcile what I saw @ sea with what's under the water .
There is /are basic things ,like deadrise and other stuff see post #15 .
Shaft angle ,I don,t like to see it high .-waist of fuel , Cog issues , bow high ,---- that what that tells me
Flaps /trim tabs --- don,t like to see oversize ones --- what adverse hull dynamic are they trying it hide ? -that what that tells me
Weight distribution ,agree v important ,you do see a lot of bow high FB boats abouts look as if they are about to launch into the air .
Judging by the frosty reception from hull form alone ,perhaps we should leave that one ?

Saw a Boston Whaler outrage 32's recently ,nice hull form ,even with big outboards on shifting the Cog. Deep v high deadrise ,lifting stakes ,Caroliner bow flair --- yup pretty obvious .

 

[Bouba]

I think the opening narrative is the main conclusion

"Whether your boat has a large engine or a small one, one bunk or a dozen cabins, a gourmet galley or a one-burner stove, there is nothing — absolutely nothing — that will make as much difference to your boating pleasure as the design of your hull."

Reading this forum just wondered ,sensed the impression this "design of the hull " stuff has somehow got lost these days .
It's not about ranking or comparing as the article infers there's no perfect shape ,depends what you want from the boat ,how you mostly plan to use it ,
Just wonder bit like golf if people know here's different shaped clubs for different job,s and with boats why the hull shape seems to be low down in the pecking order ,

I,am not saying just by looking under the skirt ( if the hull is covered -boat dressed up at an indoor show ) I can tell which is as you say is "best " - depends what you what to do with it .
If it ,s rough weather performance ,anti slamming ,smoother ride and so on ,which I suspect you are referring to ?
It would be helpful to glean some idea to save wasting time as I did with the recent Rivale debarcle .
I had witnessed a 44 slicing through wave previously and crucially seen some out of the water @ dealers .
Saw a deep V ,high deadrise , low shaft angle ,small rudders ,fine entry ,not too beamy ,no flat slamming sections to speak of .
So I could see ,or I thought it was pretty obvious ( without naval artictects experiance ) that hull form was the answer .

Next boat show I pre-arranged a demo on a Rivala 52 .I did not ,and still have not seen the underwater hull shape .Boat was in .
You can see /feel the beam that's all in the water ,wow what a disapointment ,real disapointment .
Slammed in nothing sea ,bang ,crash ,wallop etc had to slow down to 22-25 knots

That's the point -if only there was a way ,a prognostic or series of prognostic indicators to give some idea .
We wasted a day . Compete waste of time ,
Fortunately at least I had a sea trail easly laid on no strings ,deposits etc -walked away .

Arranging multiple a sea trail could be a time consuming affair ,so it would be nice to somehow be able to shorten that list

Think of it of test driving a car ,without a degree in Mech eng ,you can make a short list just by looking ,as the article ,says a Rolls Royce looks different to a off roader etc ,ground clearance ,chunky tyres etc .

Back to boats ,above water ,theres the bow area ,some like Cap Camerats ,Jeaneau ,Bertram,s have a Caroliner flair .Concave - they ride dry ,deflect the water away from the occupants .I have seen that .
Others have what appears an inflated almost bubble sides /bow ,kinda convex ,they spray water at the occupants ,wet ride .

So there's an example of eying up hull form before,go any further .

Flat ish stern sections with a fuller ,less sharper bow ,oversized trim tabs ( compared with similiar size ) are just a few examples of hull evaluation .
That I would tend to walk away from -save wasting time ,there 100 ,s out there .
In other words we wouldn,t get to see the colour of the cabinetry , how flat the saloon floor is ,or write down my details ,fight with the "gate keeper ", wait for my "personsal assistant " or receive junk e-mail etc

I had always wondered why they do put a skirt on the hulls at boat shows. I thought perhaps it's to hide their proprietary secrets from fellow exhibitors. Perhaps to show what it looks like on the water, maybe even to cover up a hull that's been in the water so is no longer perfect and shiny. But to stop people, with preconceived ideas, from turning away before they can get your details and charm your spouse with the interior is brilliant. I don't mean this in a sarcastic way, this could be the reason.

 

[oldgit]

This forum is probably the best filter you could find to divide those who will have the slightest interest in what lies beyond after the shiney gel coat disappears under anti foul.
Hence those victorian ethos "modesty skirts" covering a boats unmentionables at new boat shows, there to protect sensitivities of the viewing public.
A curious custom which mercifully has yet to reach boatyards and brokers websites.
As for the differences between Princess and Fairline hulls many earlier boats had exactly the same hulls and designer. Even older boats were built in the same factory before being moved by lorry and fitted out.
Suspect the most popular and successful designs were all discovered years ago by trial and error, a few notorious white elephants still lurking to catch the unwary or less fussy out there.
Boats that chine ride or which are impossible to helm from downstairs when planing, spring to mind.
Cannot see over the bow when underway ?......why not hang a heavy inflatable from davits on the stern and make it even worse.
All CAD modern hull designs are doing is rearranging the deck chairs ?

 

[rbcoomer]

I think it's more simple than that - the staging allows you get a more typical aspect similar to when it's on the water. When the boats are stowed ashore it also stops kids etc falling between hull and staging and the H&S investigation that would follow! Shows are more about the dream too, if your serious they probably expect you to go back or to have researched beforehand?