Sea conditions v.s. size of boat

captainalex

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It is necessarily true that the bigger the boat the better it handles the sea conditions. Obviously lenght and beam will make a difference but how much?. Boats such as the sunseeker superhawks/thunderhawks/tomahawks are all sleek in design and therefore the bow is much lower than most boats of its size. Whereas Targa 52 has a much higher bow compared with say Superhawk 50, close in length. Would this make a difference?.
I have experienced some poor sea conditions travelling from Monaco to Antibes in a sunseeker thunderhawk 43, swells of about 1.5-2m ( bigger waves 2-3m) head on. travelling at 16 knots the boat had a tendancy to plough its nose into the following wave bringing part of the wave over the bow and into the cockpit, is this dangerous?. There are similar boats which have had windscreens smashed and deck windows crushed from similar conditions.
 
i think hull form makes massive difference. Baia claims they can wham along in worse conditions that other boats (inlcuding sunseeker) because of deeper vee and in a targa in lumpy sea doing 15knots a 63footer stormed past at 30+ knots. It is said that the baias aren't as well put together but er, that sort of ttreatment must give it a good old battering...

Yep, it is not at all unheardof for the whole top of sportscruiser to get the screens wiped off in a big wave. Targa48 #1 did this i believe. Structurally tho, open boats can't be as natirally solid in such circumstances as something with a roof onnit, really, like covertible car.

I wd be suprised if this happend in sof med tho very often - short waves don't have the mass of same height wave with longer period found in uk/atlantic frinstance.

Sepretly, altho i know you are a total fan, SSqueakers aren't known as particularly incredible-wow build quality/strength so it makes sense to go carefully. There again, not sure if many/any sports scuisers would ESPECIALLY beefup an open cockpit - sunny-day boat innit, really? Worth really testing the side windows for shake etc - tho i bet they won't like it at a boat tho, heehee.

In highish seas, instead of ploughing "head-on" - try speeding up tacking - handsteering the boat at 20 knots praps 35 degrees off the head-on route, and "stealing" across the odd wave. Mind you, it really REALLY rolls so you will have to have some game people on board who don't mind their puter getting smashed - ask moose#1...
 
a chap with a Sunseeker 58 predator had his cabin flooded( not flooded but drenched in water) in a trip back from St Tropez in heavy seas. Waves ripped the hatchs off and consequently water in cabin.
 
Computer is still working but you don't know how to tighten up a Vaio screen do you? After 10mins of typing the screen either folds flat on my fingers or begins to look at the roof.

Sorry for the thread drift cap'n alex!
 
Re: jeez

sheet, that's a bit bad innit! If the hatches were fwd facig that's a poor design/build issue. If the hatches were fwd facing AND a teeny bit open, that's a combination of poor design/build AND twatish skipper, a common sunseeker problem ( - present company excepted, of course - none of the nerks i'm talking about would raise any concerns about their incredible boat or boating skills, ever!)
 
Our boat has quite a deep v so no problem zooming along in fairly roughish conditions. The down side is we get wet a lot because the shape of the hull launches the water up rather than out. Going faster actually improves things cause by the time the water has reached cockpit height we've blammed past it.
Very little slamming with a deep v hull and a smoother ride.
 
i agree with your point that speeding up can sometimes help. In the superhawk/thunderhawk it tends to handle much worse going at 20 knots. In July/August rush hour out of Pampelonne(spelling?) its often a smoother ride at 35-40 knots than at 25 konts.
I think we suprised the crew of a leopard soprt 21m when in a strong f4 we emerged from its wake about 10ft in the air. But the boat lands softly every time so doesn't seem to do any damage to the hull...not sure tho.
 
Hi

personally I think hull design is far more important than just physical size. But if its a badly designed hull then id go with the biggest badly designed hull I could find.

If the hull is designed well then id rather be in a 30 footer than a 50 footer with a bad hull

Its all to do with the intended use the boat builder wanted for their designs. My brothers 33 foot Formula cruiser it has 24 degree deadrise and 7 foot cabin headroom, so quite a large air draft, I will take that out in anything, but some of these bigger flash boats just arent up to the job both hull and build quality.

I also think knowing the boat your in, knowing how to trim it up to suit conditions and how it is going to react in certain conditions makes one of the biggest differences to the weather you can use it in.

Kevin
 
##I have experienced some poor sea conditions travelling from Monaco to Antibes in a sunseeker thunderhawk 43, swells of about 1.5-2m ( bigger waves 2-3m)###

Call that poor conditions????for a SS 43?
I think that some members hereabouts wd consider that not even worth putting oilies on for
 
seriously tho..... design of hull makes a huge difference in handling seas for comfort.
For good design look at the Botnia targs or Olisinski designs altho some drier than others and less prone to stuffing
 
Well I've done the Mallorca to Leucate trip in one hop, 200+ nm, force 5 on the nose almost all the way... ave 18 knts in a T52, no hatches or screens smashed.

Wasn't the most confortable trip ever but not too much slamming and nothing left loose to fly around and break.

Obviously had some water over the top but had canvas up so no probs.

The 20 tonne displacement is a huge difference, compared to the 9tn of the last boat. T52 felt safe and "planted" in the water and could have travelled faster but didn't see the point in abusing the hull more than was necessary.

Not sure what the displacement of the SShawk 50 is, but can't be that far off.
 
Went from St Catherines on the east coast to St Helier on the south coast of jersey in a 6-7 wind vs spring tide round the notorious violet bank thru brett passage, unwise usually BUT we were in a botnia targa 27 and the insurance at St Caths ran out that day. Held a minimum 18 knots the whole way. truly amazing as no spray hit the windscreen and felt o so safe. the same trip in a different boat could have been a much more nervous experience
 
FWIW, I dont think a deep V is necessarily an indication of seakeeping. As you describe, the Sunseeker Hawk series being very slim and having a ddep V hull, tends to ship waves over the foredeck. In fact I heard a story about one of these broaching on a delivery trip because it buried its bow in what was apparently only a moderate following sea. These boats are basically built for getting to the nearest bay in as little time as possible and coping with an inshore chop
What you need for ultimate seakeeping is forward buoyancy ie. the ability of the bow to rise over a wave and stability ie the ability to recover from roll. Whether a boat is comfortable or not in a head sea is not really material as you always have the option to slow down
Weight is an issue but it rather depends where that weight is located. No way is a multideck power boat with a high CoG as seaworthy as a heavy keeled sailboat of the same weight
 
Hi

I agree with what you say in parts but a deep vee is definitely a sign of sea keeping in a planing boat BUT a badly designed or underdeveloped deep vee like perhaps the Sunseeker - not a true offshore boat in any shape or form, allows this ploughing into the waves to happen because the designers go for pretty looking pointy shapes without thought to the important aspects that deep vee boats need; two things primarily - a constant deep vee, unlike the Hawk and a flaring of the hull sides towards the bow of the boat to push the water away and DOWN giving the front bouyancy without the need to flatten the nose and losing the true deep vee configuration- this is where these offshore look -a -likey sunseekers let themselves down its not pointy you need but deep vee, a big difference

an example of this is sunseekers xs2000 the hull shaping to the bow of the boat is nothing like their Peter Stringfellow range- it is a true offshore deep vee hull

IMVHO

Kevin
 
Huntons come to mind here. Genuine offshore racing heritage, that means long slim shape compromises accomodation, but will keep going through rough stuff at speed
 
When is a deep v not a deep v?

The Hunton aside I don't think any of these boats mentioned above are true deep V but modified deep V's. Pointy deadrise at the front, flattening out at the back.
 
Re: When is a deep v not a deep v?

No, I dont think so. AFAIK, the Sunseeker Hawk series have a constant deadrise from bow to stern. Its yer common or garden Sunseeker, Sealine, Fairline, Princess etc that have variable deadrise flattening out at the stern ( I much prefer the phrase 'warped bottom')
 
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