Pilothouse Variations -- Boreal

[neilpride]

[QUOTE=TJ D;2131696]

Originally Posted by neilpride

Nice boat, out of curiosity, where rest the mast , i mean that structure like a pyramid with a Hatch in one side??


The 'Pod'? The dog needed a place to sleep on deck.

Not really. The reason that was done was to bring the structure of the boat up to the point where the main would still have more or less conventional geometry, but the boom loading is taken up by the vessel and not the mast. It's all about not interfering with the column loading on the mast.

The boat was built in 1996, and carbon masts were still relatively new. There had been some failures due to boom loading, this was the answer. Probably less important now than 20 years ago, but the engineering is still sound.

The pod is very heavily built, with 2 full-width bulkheads below to take the load. No stripper poles below...

TJ

Wow, I get it now, the gooseneck is in the pod, I guess the wall thicknes in the carbon mast is not so great for a gooseneck , I see few carbon spars with the same problem, the solution I see this days its a thick CF patch in the gooseneck area, drilling and taping in CF its tough, but anyway nice to see the purpose of the pod, thank you for the info.

[Polux]

Originally Posted by neilpride

So,who say keel stepped mast are more efficient, sorry I don't get your point...

Sometimes you are quite annoying or you don't know the mean of the word efficiency? You have answered what you are asking

Originally Posted by neilpride

..
Another point to consider is deck stepped masts have a 20% or more compression load compared to a keel steeped mast, is obvious the uppers and lowers are tighter than a keel stepped mast, putting extra strain in chainplates and tangs, if you are unlucky and one wire snap in a deck stepped mast is over, in a keel stepped mast if you are fast at the helm and make a tack really quick you can save the day, a keel stepped mast can stay upright with a lower or d1 d2 gone, overall I can say keel stepped mast have a better life span and are easy to tune ..

Originally Posted by neilpride

And, I don't understand your 2 point, what you mean,? racers choose keel or deck stepped mast for what reason? ...

And regarding this I don't understand how you don't know that: All ocean race boats have keel steeped masts and even the vast majority of performance cruisers have them too. The reason is obvious and relates with what you said above: they are more efficient.

Originally Posted by neilpride

Interior design??? lol, how?
Preventing rain ingress? actually with a inner dam in the stick you get a bone dry bilge, just saying.

Regarding interior design I don't understand your doubt. On a relatively small interior a mast is not only a big visual intrusion. A compression post is much smaller and much more easier to combine with the interior design.

Most boats with a deck stepped mast have some rain intrusion, not much but some drops along the mast when the rain is heavy. I have on my boat the system that is a rubber collar made with two component products. It is one of the best solutions but you know that the mast is not a rigid piece and flex. Those flexions produce always some way for some water to come in.

Mine is pretty dry but I know lots of them (recent boats) that let some water in when the rain is heavy.

[TeddyDiver]

Originally Posted by Dockhead

Well . . .

Next summer, God willing, I will sail through the White Sea and Barents Sea and across the top of Norway, more than 70N, and that is definitely high latitude sailing in every sense of the word.

Then you'd defineatly take a stop in my whereabouts, from Varangerfjord to Tanafjord. My treat

BR Teddy

[TeddyDiver]

Originally Posted by Polux

And regarding this I don't understand how you don't know that: All ocean race boats have keel steeped masts and even the vast majority of performance cruisers have them too. The reason is obvious and relates with what you said above: they are more efficient.

Lighter and thinner, bottom line is higher RM and less induced drag.. Efficient is bit vague expression.

[neilpride]

Its confused like usual, First I never say racers boats have deck stepped mast lol. 2 the interior can be designed to hide a compression post or a mast, 3 Paolo your Comet have a keel stepped mast? how can you say deck stepped mast have some water intrusion, do you understand what you write on those posts?

[neilpride]

This is a Comet 41, quite honest the mast is there , in the middle, could be a compression post diferent? not much for me, a shiny pole in inox or a aluminium piece of mast make no diference to me.

[neilpride]

And others builders have a elegant interior design to accommodate and hide the mast, in this case a bene 50, the spar is between the 2 fwd cabins , you cant see it because is encased in a piece of furniture...

[Cadence]

Originally Posted by neilpride

Its confused like usual, First I never say racers boats have deck stepped mast lol. 2 the interior can be designed to hide a compression post or a mast, 3 Paolo your Comet have a keel stepped mast? how can you say deck stepped mast have some water intrusion, do you understand what you write on those posts?

I was in the same quandary about the leakage on deck stepped masts? Let it go. It's not important. Probably 75% of posts need to be taken with a grain of salt.

[hoppy]

I don't know what this yacht is as it has no brand markings, but it's pilot house or is it deck saloon, looks to be rather sleek and perhaps relatively good for windage

The other day it was bow first and there was someone sitting in there. They were quite visible and I think they had probably good visibility from inside.





The boat also had twin rudders that were skeg hung. It makes me wonder if it has a lifting/swing keel and the skegs are so it can be beached.




Sent from my iPhone using Cruisers Sailing Forum

[Polux]

Originally Posted by Snowpetrel;2131304..

..been to Antarctica 3 times on a boat with twin rudders and grew to hate them with a passion. ...

Particularly bad control when broad reaching in a big sea. Say on stb tack As the boat powered up and wanted to round up we would need to wind on some port rudder. ....

If you had problems with twin rudders on a beam reach the boat was not well designed, assuming we are talking about the boats of the same size and weight. The Twin rudder is at his best particularly at that point of sail when they allows a bigger boat control particularly near broaching situations and in bad weather. That is why they are used widely in today's sailingboat design.

Originally Posted by Snowpetrel;2131304..

....and were incredibly vulnerable if we ran aground.

Hard to understand why you say that too. Twin rudders are much shorter than a single rudder so they should be a lot more protected in case of grounding.

Also because they are much shorter they can be
more strong since the forces that acted on a rudder in case of grounding or shock will be multiplied by their length (and twin rudders have about half the length), not to mention that in case of rudder lost, in a grounding or collision, on a two rudder set up you can still sail the boat.

[neilpride]

Polux normally twin rudders are linked together to the helm setup, if one get stuck the other is stuck to, unless you snap the rudder free from the boat maybe the other can do the job, but 99% of the time they get stuck and the other suffer the same fate.

[Polux]

Originally Posted by TJ D

Ahh, twin rudders. We have 2 on Rocket Science, and I must confess that we have a love/hate relationship with them.

...

1. I've found the sailing performance to be really stellar. One rudder is always in pretty much the right place when beating or reaching, giving us control that we have not found on a single-ruddered boat. We can reach at 12 knots with one hand on the wheel. It's quite something, and while the rudders don't create that condition all by themselves, they do contribute.

2. At surfing/planing speeds, they really come into their own. The boat tends to flatten out anyway once she gets up on a plane or starts surfing, so both rudders are working together. At displacement speeds, however, I have noted some degree of the difficulties that Snowpetrel describes.

Generally, I think that the twin rudder trend is probably not all that beneficial for boats which aren't being sailed quite fast. They are probably more of a liability on something along the lines of a Halberg Rassey than an asset.
...
TJ

I don't agree with you in what regards not being beneficial in boats like the Halberg Rassy 44. Twin rudders allow for a better control with smaller length rudders on beamy boats specially when the boat is heeled and near the limit.

That is easy to explain and Finot has explained it 20 years ago through some very clear designs: Beamy boats with the hull brought back, like the new Halberg Rassy designs sail upwind with an asymmetric water plane, one that increases performance (increasing LWL) but that creates problems with a single rudder that is not in the axis of the boat. A twin rudder solves that problem since it is placed on the axis of the water plane when the boat is heeled.

[Polux]

Originally Posted by neilpride

Polux normally twin rudders are linked together to the helm setup, if one get stuck the other is stuck to, unless you snap the rudder free from the boat maybe the other can do the job, but 99% of the time they get stuck and the other suffer the same fate.

No, as you should know before they come to cruising boats they were widely used for decades in offshore racing boats, specially beamy solo racers and I know of a huge number of cases where a boat lost one of the rudders and come more slowly to port for repair. Normally they are designed to break on a strong collision, not to be jammed. Your percentage is way out.

Don't know of any boat with a twin rudder that after having lost a rudder lost steering, except a cat case with a new boat but that was a weird case, no collision and bad design.

[Cadence]

Sometimes I have to believe some people are arm chair sailors. Granted I'm not the best.

Speaking of what you have read someplace? Or speculation on design without any actual education or even serious reading.

Seems like people with nothing else to do. It kind of muddies up the real contributions.

[Polux]

Originally Posted by neilpride

And others builders have a elegant interior design to accommodate and hide the mast, in this case a bene 50, the spar is between the 2 fwd cabins , you cant see it because is encased in a piece of furniture...

I believe you are a bit confused. The boat you posted is a 1995 Beneteau 50 and doesn't have a keel stepped mast, but a deck mast with a compression post. It is because it has a smaller compression post that it is possible to hide it on the furniture. Look:

In fact it is a very good example of the opposite you are trying to argue

Compression posts due their smaller size can be disguised inside chrome rounded bars or completed involved in wood making a lot more easy to design a nice boat interior specially in boats not bigger than 50ft.

It may hard to understand for you but most people don't like to see a mast inside the boat, not even when the interior is a nice one:

They rather prefer the liberty and more opness a compression post allows (all boats have about the same size):




That is why almost all main market cruisers have deck stepped mast with a compression post and almost all performance cruisers have keel steeped masts: The first privilege more interior design quality the others privilege more efficiency.

From Beneteau Oceanis have deck stepped masts, First have keel stepped masts.