Is Semi-Displacement Hull better than Deep V Hull ?

Yes but this is a bit going from an extreme to another, subjecting the choices to the need to drive 30+ knots in 5/6 Beaufort - like this is the normal scenario.

We all know that when is foamy we don't go out, specially in the med what is the point in slamming your boat around just to rock and roll when at anchor. 99% of cruising days are flat water or small chop with the occasional 1% when you misjudge and there worse can happen you cruise back at 8/9 kn the usual 45 deg to waves etc. Is not that once a bit of wind comes out the 30+kn deep-v will be saved and everyone else will go down to the fishes.

I know is nice that in a 5-6 Beaufort deep-v will be king of the hill. But trading livability etc for that once-in-a-moonlight scenario - not sure.

Apartments like the Navetta gets made and are very successful because in the general equation that 1% 6 Beaufort 20 miles off scenario does not really play a role, if I compare the place on a Navetta with my Primatist (which is 6 foot shorter but still) is like going from a villa to a cave. And this is value for a lot of people. The boat I actually own, Primatist G41, was bought because missus said "oh what a fantastic lounge / suntan area ! And 6-8 people can sit around the table so social / party / friends", my concerns about volvo feets etc did not really played a role at all. Turned out to be a fantastic boat btw.
 
prinex said:
Yes but this is a bit going from an extreme to another, subjecting the choices to the need to drive 30+ knots in 5/6 Beaufort - like this is the normal scenario.

We all know that when is foamy we don't go out, specially in the med what is the point in slamming your boat around just to rock and roll when at anchor. 99% of cruising days are flat water or small chop with the occasional 1% when you misjudge and there worse can happen you cruise back at 8/9 kn the usual 45 deg to waves etc. Is not that once a bit of wind comes out the 30+kn deep-v will be saved and everyone else will go down to the fishes.

I know is nice that in a 5-6 Beaufort deep-v will be king of the hill. But trading livability etc for that once-in-a-moonlight scenario - not sure.

Apartments like the Navetta gets made and are very successful because in the general equation that 1% 6 Beaufort 20 miles off scenario does not really play a role, if I compare the place on a Navetta with my Primatist (which is 6 foot shorter but still) is like going from a villa to a cave. And this is value for a lot of people. The boat I actually own, Primatist G41, was bought because missus said "oh what a fantastic lounge / suntan area ! And 6-8 people can sit around the table so social / party / friends", my concerns about volvo feets etc did not really played a role at all. Turned out to be a fantastic boat btw.
Click to expand...

I love the Swift Trawler 41....its go everything i need and looks fun to drive. A great weekend boat (y)

swifttrawler41fly-ext1.jpg (y)
 
My second boat was a copy of a raceboat which I built myself when I was 13. Very Deep V - I used it a lot for Waterskiing - and learned it the hard way: Deep V was a real bad option. With a good skier on Slalom the boat felt like it would capsize. (Pro Skiboats are almost flat) The sportfishers may be very fast - some of them are well known for being terrible to be onboard when fishing ---> Deep V = rolling at trolling speed (bad for fishing) - Portofinos point of View is well known, but pleasure boating is more than just speed. If your GT in the Sunset is important for you the Deep V is maybe not the right option (Unless you speed home for your GT)
Semi Displacements are From / to - You may even ask why should a SD waste so much HP to reach speeds of 30 knots = your choice. For others the SD are purely to reach speeds exceeding the "Hullspeed" - Your choice.
There are good and bad boats, both SD and DeepV and I fail to see why it should leed to discussion between SD or DeepV . Which is the best boat Nordhavn or Itama.....
 
Portofino said:
See what I mean you have to test drive them more so nowadays .
PeteM s post #27 statement is wrong “ The planing hulls from the big manufacturers will be perfectly adequate for normal use.”

That’s a cop out for poor design.
I have explained and detailed how something crap sea keeping wise gets through to production and boat shows and woos punters cheque books open .

Take another one the FL 62 GTO , it new barely made over 30 knots and reading between the review lines , the journo test the ride at speed , well it’s mid 20 knots speed was “ a little lumpy “
Exactly the same reasons as the Rivale 52 they ballooned up the mid sections to stuff in what they thought punters want .
Plus for cost reasins weedy motors .
Those big sport fishers in my post #33 sit between 30-40 knots all day a few nearer 40 .
Power / Hp and the finer entry and mid section s , the opposite of the GTO 63 which has weedy power and flatter mid sections = slower and a tendency to get bumpy .

They ( builders ) are all at it btw it’s like a arms race for accommodation/ floating apartment and Absolute are in the thick of that trend .Low deadrise for IPS + flatter mid section for accommodation and low Hp to be price competitive.

Interestingly and quite telling is Genoa .That show recently there has been some windy days say 3 out of the 6 .
Note the builders that refuse to go out / take punters above F4/5 , to play in the white horses .

Equally note those that demo on every day irrespective of the conditions and it’s not just ribs .


Very interested in your feed back after demo / test drives Shane , I do hope you actually test the short list before committing?
In other than mill pond calm .
Click to expand...
Porto, above is further evidence that you don't understand most people's priorities for choosing a particular boat.
Portofino said:
No you are wrong Pete .
See my post #32 …….the last line “Sold over a hundred units though .”
And the recent Genoa trend for the floating apartment ( with robotised parking :Dgadgets) guys to cock off demos with the first sight of a white horse in the bay .
They want that ink to dry first . ;) .

Not being judgmental Pete , just saying it as it is .
Click to expand...
Why would you go out when there are white horses in the bay, when you can choose a calmer day, anchor off and have some lunch and a swim?
 
marcochi76 said:
Wonderful analysis Porto! I have an excuse now to strop dreaming of the Rivale (that I will never be able to afford!!!) ?

Sorry to go off-topic...
How would you consider the hull of a Princess V39? Deep V, medium V, slam lover?
It looks deep V at entry point, then 21degree at midpoint and 15degree (very flat) at aft.
That is very visible in the attached photos.
Click to expand...
Good hull, pretty standard Bernard Olesinski for UK made boats. There's an experienced owner on Youtube who motored his up from the Med then sailed it to Russia.

Not sure anyone would want to do that in an Itama :)!
 
petem said:
Why would you go out when there are white horses in the bay, when you can choose a calmer day, anchor off and have some lunch and a swim?
Click to expand...

Not trying to defend portos stance , hes a big boy , he can defend himself , but I would also prioritise ability to handle a decent chop over interior space, In the summer in mallorca, it almost always gets a bit white horsey in the afternoons, theres no avoiding it, unless you stay on anchor until 8pm, so a comfortable hull is quite a nice thing and for me worth compromising some other things for - but I appreciate I'm in a minority in this.

Its (white) horses for courses though isnt it - You choose what suits your usage best and make compromises, almost everyone has to do it. I think the majority of buyers favour more interior space over a hull that can do 35 knots in a force 6 - hence the prevalence of that style of boat. Theres no wrong or right with this, just personal preference.

We used to have a sealine s34 - amazing amount of interior space, but I hated the way it went though a chop - it drove like a bus.
 
Last edited:
Hey guys Shane is not considering a deep V .Thread title is erroneous. Thought we sorted that further up the Navettas are not deep V s as isn’t that Riva 52 or the FL 62 GTO and certainly not the nice Priny mentioned .
Deffiniton accepted by naval architects is dead-rise in excess of 20 degrees .

This is SD vs true Planing .
I would advocate now we have been drip fed the cruising ground a planing boat with as deeper V as the apartment comprises he can put up with . As that loop and amongst those keys off shore it can and will cut up into white horses territory .
Waiting out weather in the floating “apartment” burning up berthing fees in some gawd forsaken 8hit hole is no fun .
 
julians said:
Not trying to defend portos stance , hes a big boy , he can defend himself , but I would also prioritise ability to handle a decent chop over interior space, In the summer in mallorca, it almost always gets a bit white horsey in the afternoons, theres no avoiding it, unless you stay on anchor until 8pm, so a comfortable hull is quite a nice thing and for me worth compromising some other things for - but I appreciate I'm in a minority in this.

Its (white) horses for courses though isnt it - You choose what suits your usage best and make compromises, almost everyone has to do it. I think the majority of buyers favour more interior space over a hull that can do 35 knots in a force 6 - hence the prevalence of that style of boat. Theres no wrong or right with this, just personal preference.

We used to have a sealine s34 - amazing amount of interior space, but I hated the way it went though a chop - it drove like a bus.
Click to expand...
Yup 16 seasons in the Med the afternoons often cut up to white horses territory or a the wind changes direction .
That nice down wind f3/4 run to the sheltered anchorage can easily turns into a epic return trip .Not good for initiated guests !

Its a bit more than 1% in my experience Cote d Azur , Liguria , Corsica , Elba .More like 30/40 % .

Yes I can see some folks pov sat in the marina or as you say hanging around until dusk until the wind drops if they dare to have gone out that day .
Mostly with aps etc weather forecasting has improved recently granted , but winds do come from no where and after a blow there is sometimes no white horses as such but a nasty swell a hanging about few days .

Would imaging those Florida keys re tide , currents , wind , are a boat passage planners nightmare .
Haul over inlet anyone ? :D
 
petem said:
Good hull, pretty standard Bernard Olesinski for UK made boats. There's an experienced owner on Youtube who motored his up from the Med then sailed it to Russia.

Not sure anyone would want to do that in an Itama :)!
Click to expand...
Windy - Pete the marque of choice for choppy Baltic seas .
Tip watch what the locals prefer . :D.

They are not floating apartments by any stretch of the imagination.
 
piratos said:
My second boat was a copy of a raceboat which I built myself when I was 13. Very Deep V - I used it a lot for Waterskiing - and learned it the hard way: Deep V was a real bad option. With a good skier on Slalom the boat felt like it would capsize. (Pro Skiboats are almost flat) The sportfishers may be very fast - some of them are well known for being terrible to be onboard when fishing ---> Deep V = rolling at trolling speed (bad for fishing) - Portofinos point of View is well known, but pleasure boating is more than just speed. If your GT in the Sunset is important for you the Deep V is maybe not the right option (Unless you speed home for your GT)
Semi Displacements are From / to - You may even ask why should a SD waste so much HP to reach speeds of 30 knots = your choice. For others the SD are purely to reach speeds exceeding the "Hullspeed" - Your choice.
There are good and bad boats, both SD and DeepV and I fail to see why it should leed to discussion between SD or DeepV . Which is the best boat Nordhavn or Itama.....
Click to expand...
American fishers are not deep V at the stern , indeed very flat at the fighting chair position.
They do have higher CoG s and suffer a lot of pendulum effect like sail boats due to the tower .Hence slow speed roll tendency.

Every one knows Mastercraft ski boats are almost flat at the stern to create the best wakes .

Its never been a discussion between SD and deep V as the Navetta is not a deep V .
Quote Shane ( his thread )

“
I was just talking about style of boats in my own layman terms

Im sorry if i wasn't using the correct technical jargon but i was trying to just give a jist of what i meant

But i keep learning and this forum definitely keeps me on my toes (y)”


Hes not thinking Windy , Baia , Magnum , Itama , Rizzardi , Otam , Fountain , a few others the true deep V s .
 
I absolutely love the Cranchi T55....to me its the best designed Trawler style boat out there

But for some really strange reason they didnt include a helm door....what were they thinking?

And it has IPS drives ?

 
petem said:
Nothing wrong with IPS if you're buying new. And particularly if you're a newbie.
Click to expand...

I love the IPS system integrated with the Garmin Glass Cockpit and Joystick

But like ive said in previous posts IPS is probably not the best option for the Intracoastal Waterway

It will probably be ok but ive read that there can be some quite heavy debris like logs etc

(y)
 
It doesn't take heavy debris to stop an IPS boat.
Just in case you didn't realize it, a fishing line caught in an IPS can be enough to emulsionate the oil inside it, which means that you must stop the engine involved PDQ, to avoid catastrophic damages.
Unless BOTH pods are affected, in which case you should drop the anchor wherever you are, and wait for a tow.
Oh, and it takes a liftout for the necessary repairs, anyway.
But don't bother checking the brochures, for some reason they must have forgotten to mention all that... :ROFLMAO:
 
petem said:
Nothing wrong with IPS if you're buying new.
Click to expand...
Aside from the fact that what I just envisaged has the same probability to happen upon the very first sea trial, as well as at any time in the future.
BTW, with no warranty to cover that!
 
MapisM said:
It doesn't take heavy debris to stop an IPS boat.
Just in case you didn't realize it, a fishing line caught in an IPS can be enough to emulsionate the oil inside it, which means that you must stop the engine involved PDQ, to avoid catastrophic damages.
Unless BOTH pods are affected, in which case you should drop the anchor wherever you are, and wait for a tow.
Oh, and it takes a liftout for the necessary repairs, anyway.
But don't bother checking the brochures, for some reason they must have forgotten to mention all that... :ROFLMAO:
Click to expand...

You really know how to take the fun out of it dont you?

You'd probably tell me not to buy a 'Lancia - Integrale' because it has terrible electrical wiring regardless of how much fun it is to drive

:LOL:
 
D
ShaneAtSea said:
I love the IPS system integrated with the Garmin Glass Cockpit and Joystick

But like ive said in previous posts IPS is probably not the best option for the Intracoastal Waterway

It will probably be ok but ive read that there can be some quite heavy debris like logs etc

(y)
Click to expand...
Don’t logs float ?
 
ShaneAtSea said:
I love the IPS system integrated with the Garmin Glass Cockpit and Joystick

But like ive said in previous posts IPS is probably not the best option for the Intracoastal Waterway

It will probably be ok but ive read that there can be some quite heavy debris like logs etc

(y)
Click to expand...
Daughter has done N.Y -Palm Beach 4 times with IPS touched the bottom a few times and 1 haul out for damaged props. Due to wait for new props to arrive they now carry spares and have never needed them!
 
You must log in or register to reply here.

Share this page

Top