Hull design

[Dave_Snelson]

In looking at the hulls of motor boats on hard standing in marinas, I find that most are the same.... except for my Windy. The intricacies of the way the strakes are fluked at the stern and the shape of the way various parts enter and exit the water are different.

The handling of my Windy at any speed, other than in a harbour, is impeccable. Is this Windy's secret? - if so, why don't other yards just steal this design?

I'm not being deliberately big headed about my boat (heaven knows, I'm at the poor mans end of the market!!) its just that when I was anti-fouling, I noticed just how much design had gone into my hull (and seemingly not others).

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[BarryH]

I've often wondered the same. Windy's, and later Draco's from the same stable" are renowned sea boats.
How do you find the Windy going from displacement to the plane. Our boat seems to be one of the only boats I've had that does'nt seem to have a hump. Goes from displacement speed to the plane effortlesly. Takes a head sea better than others I've tried. The bow has a fine entry and the keel is carried foreward a long way. The big reverse chines make it grip in turns, wish I could say the same for the prop". On the odd occasions I've had it airbourne it lands softly and theres no thump thump making speed over a chop.
If only it was a bit bigger.

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[BrendanS]

Interestingly, one of the first thing that seasoned mobo's mention when on my boat is the lack of hump. There's none of the marked bow up characteristics you find on many boats, just seems to rise up out of the water on an even keel. When one of the boat mags did a comparison of similar sized boats recently, they said this hull was technically superb. Very similar characteristics to what you describe

Dave, if you think a lot of work went into your hull, take a look at the pictures of a Regal fastrac hull. The Windy hull, like the Regal, probably has patented features that cannot be copied

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[tcm]

ooh can i join in this? I agree that brendan's , barry's and daves boats are indeed really quite fab - and i'm not being crreepy crawly about this- and i've noticed that other boats are a bit rubbish. Is it a design thing? Or were all the above just born with natural ability to choose their ideal boat whereas all the rest of us seem to be lumbered with another plastic thing full of teak, metal and dodgy lectrics?

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[BarryH]

"plastic thing full of teak, metal and dodgy lectrics?"........ooh ok I'll do a swap wiv yer. On the basis that I'll give you my boat with full tanks as long as you give me your boat with full tanks. Oh and the tanks don't have to be full when we give'em back.
Don't think you'll go for it tho. I've no bog on my boat, whereas you might have...umm....one or two!

Guy I know has the same Regal as yours. I found the fastrac hull a bit skitt'ish, or is that me or the way he had it loaded. Did like the fact that it wasn't a powerhungry hull.


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[tcm]

20 Regal

i don't actually have one of these, but almost wish i had one, to celebrate the fabulously inept branding.

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[BarryH]

Re: 20 Regal

Umm yeah, that was me being ahead of myself again, that bit was aimed at Brendan

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[BrendanS]

The only time it shows characteristics I'd describe as skittish is when you are powering over chop rather than through it at high speed. Not unstable, nor even skittish really, but spending so much time over water rather than in it is bound to feel abnormal until you are used to it.

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[BrendanS]

Ah, but if you look carefully, the thread is about hull design, and that's wot we were talking about, not that the boats were fab, and no suggestions that other things go wrong.

It's a fact that the Windy, Tremlett, and Regal Fastrac hulls have all been praised for well above average performance and handling by boating press and general opinion.

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[BarryH]

This was on flat water. The boat was running probably high 30 knots. Going thru the stakes up the wareham channel it just seem to "oversteer". The steering seemed a bit too positive if you get my drift. A bit "twichy" is probably the best way to explain it. Probably having a dinghy and outboard in the cuddy done it no favours.
Lots of room for the size of boat though. Was impressed with it. Even to the extent in playing in the aftermath of the seacats wash in poole bay. We'd run back from Yarmouth in double quick time with wind over tide. Worst bit was the Christchurch Ledges. Handled that with aplomb. Just surprised me on the flat water.

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[tcm]

ah but, see, it's chucking out time, so erm your almost certinaly correct. BUT, i think you can see the point i'm making...

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[BrendanS]

Blimey, something very wrong if it felt like that on flat water. It should be like driving a Lotus, just point and steer, and will go where ever pointed with no slip, even at over 40knts


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[BrendanS]

Didn't have a clue about boats when I bought it. Was just left alone in Earls Court for a day, and purchased on impulse cos I liked the look of it. So I must indeed have just born with natural ability to choose ideal boat

The trick of course is being able to do this next time around, now that I know a little about boats, and will be poring over reviews and asking questions, so I may be put off buying my second ideal boat by peer pressure instead of going with instinct <g>

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[jfm]

Re: Hull design Humphrey

This hump thing is overstated. I've certianly had the hump in an underpowered tender and in say 19foot runabouts. But all the bigger boats I've driven simply dont have a hump. Ours just rises on the plane, and our last one did. I was out with bigmoose recently and his has no hump. tcm doesn't have the hump ('cept when provoked, obviously). So any bigger boat (I dunno, say 35 foot up) that has a pronounced hump is an appallingly bad design imho. If anyone wants to patent a humpfree boat lettem try.

I do admit though I have only driven 8 or 10 boats 40foot up, so maybe a limited sample? Learner might comment here, he has driven 8-10,000

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[DavidJ]

Re: Hull design Humphrey

Agree
Hump certainly was a characteristic with previous 19 ft and 24ft boats of mine. The 37ft seems to stay flat all the way through with an acceleration surge when its just on the plane.


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[Dave_Snelson]

Barry,

The only time it slaps the water is when I get it airbourne whilst on its side in a turn - fair enough!!

It doesn't have a "hump" to get over when transitioning from displacement to planing - it just seems to get there.

If only its mechanicals were more reliable...

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[Dave_Snelson]

Ha ha ha this is funny!!

I came across my boat quite by accident, so I cannot claim any intelligence here. (can't claim any anyway!)

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[Deleted User YDKXO]

Not sure way the strakes ( I guess you mean the spray rails - those fin like things which protrude from the hull?) are fluked has any fundamental effect on the way the boat handles at speed. AFAIK, the purpose of those are to deflect spray downwards rather than allowing it to creep up the sides of the hull. On most boats these fade out well before the stern because the stern is always immersed in the water
I think what fundamentally makes Windys seakindly boats is the fact that they are deeper V hulls than average particularly at the forward end of the hull. The downside of this is that the accomodation volume inside is pinched. Compare a Windy to a Sealine of the same length and you'll probably see that the Sealine carries it's beam much further forward which translates to a bigger volume inside which looks good at boat shows but maybe gives rise to more slamming in a head sea. But head sea performance is probably less important than following sea performance because the consequence of stuffing the bow into a wave in a following sea and broaching is very serious so whilst its good to have a deep V forwards you also need good buoyancy forward as well to make sure the bow rises over a wave rather than doing a submarine impersonation. Some early deep V hull designs did this
I think the secret of Windy's good sea performance is a combination of a deep V hull with precise attention to the balance of the boat in a range of sea conditions

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[Kevin]

Hi

I agree with Deleted User.

There are many things that culminate in a good hull, deep v, correct strake positioning etc. boats are a compromises and thus try to balance interior space and comfort with ability at sea, along with appealing looks for marketing purposes.

An ideal offshore hull is one with a narrow beam, a deep v, say about 24 degrees BUT keeps that all the way to the bow, most boats start off with a decent v but that diminshes as you move forward (looking at the deadrise isnt a way of knowing if the hull is a good offshore hull). the manufacturers have this flattening out for the reasons of space and bow bouyancy. Narrow beams, totally important for true offshore not only diminish internal space but also allows for a less static float at anchor- something that can be important on a cruiser.

You also have to take on board that many boats are designed and tested to only a limited degree, testing its far too expensive to do on every hull over and over tweaking and tweaking, the designer will use their experience to develop a hull likely to do what they want and after testing providing that it has no major flaws will go into production, what the manufacturers is less likely to do when testing is to attempt to produce the 'perfect' hull it would be far too costly considering the number of each boat sold even by the major manufacturers.

Thus the designer used by each manufacturer will have their own charactoristics and Windy obviously has somebody whose lean is towards offshore performance where as other manufacturers will employ designers that maybe have that further down their lists of priority.

Thats why to a degree I dont always agree with some of the manufacturers claims of their boats being offshore, yes they can go offshore but not designed fully to do that, a compromise.

all IMVHO

Kevin

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[PaulF]

Spot on, for seakeeping a narrow deep Vee leaves the others dead in the water for going in the rough stuff. Broad flat bottomed caravan best for accom. It is all a compromise of performance/accomodation/marketing. Pays yer munny an taiks yer choyc! (filched by kind permision of. . . . )

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