Improving IOR Stability?

Motorbike: a hallmark of a knowledgeable person is the ability to explain concepts to those who don't know. Why can't you define clearly what "rolling to windward" is. There are two parts of your terminology: "rolling" and "windward".

 

Gonzo, you have been sailing since 1969 and you need these basic concepts explained? I dont think so, whatever game youre playing its making you look foolish. I sugest you start another thread on the subject if you are serious. As for my attempts at humour, clearly I shouldnt try a career in stand up so please excuse me as I dont intend to offend people I dont know.

Back to the OP's question it seem that the consensus is to make adjustments to sailing technique and trim, then enjoy the boat otherwise the expense involved in altering hull shape or foils etc is not worth it

 

So my only conclusion is you do not know what it means either since you can not explain it.

Why is it when I want someone to explain what they mean I get insulted?

 

Not you as well?

So you are seriously telling the world that despite sailng since a child you dont know what windward/leeward means, that you dont know what "rolling" is and that you are baffled by those relative terms when sailing 180 degrees off the wind and that you dont know what directly down wind is? Moreover you insist on having it explained to you to make a point?

C'mon Petros youre just having fun, surely?

 

I know what all of those are (better than most I would say in fact). You forgot already what my question was? I will repeat it.

I wanted to know exactly what the poster meant when he said something like "the broach occures when heading directly down wind and the boat rolls to windward".

The word windward means "toward the wind". If heading directly down wind, I wanted to understand what the poster meant by rolling to windward.

It is a simple question, I just want to make sure I understood what he meant.

 

Also, Motorbike has not yet defined what he means by windward and rolling. One of the principles of good discussions is to find as narrow as possible definitions about the subject. Motorbike answers with sarcasm and snide remarks, but does not define clearly and concisely what he is talking about.

 

What is this a tag team? Both of you mentioned rolling to windward, both of you seem pretty confused about what is directly downwind and what the relative terms windward and leeward mean and both of you seem affronted, insulted and worse. Yet you feel free to use sarcasm expecting it to ride and personal attack demanding that I educate you.

Perhaps YOU both could could explain to the world what the limit of your understanding is regarding the above and lets go from there?

Out of respect to the OP I'm out of this thread as its being destroyed, please feel free to start one entitled "What does windward mean?"

 

I would never describe a boat as "rolling to windward" when sailing directly down wind. I did not make that claim, I just want to know what they meant by it. Someone else pointed out that you are never going directly down wind, but than that would not be going directly down wind, would it? But the person who posted it never explained it. Others jump in to make fun of it, and neither did they, or you motorbike, attempt to explain it.

Gonzo pointed out that in sailing convention, rolling to windward would mean rolling to the side away from where the boom is located, even if going directly down wind. Okay, fine. That would make sense as a convention. But what if you are sailing in square rigger?

would it not be more descriptive to describe rolling toward or away from the main sail?

this is the problem with sailing terminology, much of it is narrowly used in one context and than expanded to others, which are misnomers. And much of it is obsolete terminology that has way outlived its usefulness and only obviscates the discussion.

So Motorbike, are you going to verify or correct what it means to "roll to windward" when doing directly down wind? It appears you never even followed the conversation, and chose to jump in and make fun without ever explaining yourself.

So, all I can conclude is you have looked at all this with a vacant mind.

 

Hi, Paul. Thanks for your comments.

From what you said, I take it the major reason these boats got out of control was the type of down wind sail and the massive amount of it they used.

I imagine, as sterns got wider, the situation improved somewhat. The wider stern, as I see it, gives both static and dynamic stability to the system. The static part comes from greater righting moment, per given Beam. The dynamic part comes from the boat using that portion of the hull as a planing surface, especially if the run in that area is relatively flat. This planing surface, though it may not be enough to raise the boat up on a plane, may add righting moment.

It is true that deep, narrow rudders are a bit of a fixation of mine. The reason for this is entirely theoretic. My theory is that the high aspect ratio of the rudder gives it more lift per area, making it feasible to go with a smaller area. If this rudder ever stalls, it loses quite a bit of its lift, and can become temporarily ineffective.

It is my guess that there was a great incentive to make the rudder area as small as possible.

I imagine the best way to go is with a narrow, deep rudder of generous area.

The light, beamy, centrboarder, I used to own, had one. Its area was at least half that of its swing keel. I never had a control problem except a heavy weather helm.

I once sailed it DDW, in 20 kts, with the jib and main wing and wing.

She pitched, she rolled, she yawed, like a mechanical bull, but I never lost control. But that was the last time I did that. From then on, it was down wind tacks.

My boat had a wide stern.

I imagine the rolling, at least, would have been worse, had my boat had a pointed stern. And maybe, the the rolling being worse would have removed the last margin of control.

I can imagine adding a high shouldered spinnaker to that, and seeing, as the boat rolled, the turning moment going where ever the the center of effort of that sail went, regardless of whatever I did, or tried to do, with the rudder.

(For example, if the boat rolled to starboard, the CE of the spinnaker would turn the boat to port)