Large genoa on cutter: what does it mean?

[hpeer]

Poking around here and boatdesign I’ve found a couple of other threads that address this issue of a Genoa creating excessive weatherhelm/heeling.

This one is particularly relevant.

https://www.cruisersforum.com/forums...ro-190486.html

The diagram on page 4 got me thinking maybe the problem is related to my keel shape, basically that of a landing barge. So I found this other thread on boatdesign that eased my concerns about that flat leading edge.

https://www.boatdesign.net/threads/l...g-edges.10180/

I’m still thinking my very heavy Yankee (8-10oz cloth?) is the culprit. I’m also still waiting to get some decent weather to go out and cuddle around. We moved from Jolly Harbor to Falmouth the other day, the first half was light winds and we poked along under main and light Genoa (maybe 3oz cloth?) the second half was 20+ knots directly on the nose with 5’ seas, resorted to motor sailing for that bit. Neither very useful for experimenting.

[a64pilot]

Originally Posted by hpeer

A64,

Our boat is more like the IP 38, except with a longer sprit.

Did you have any weather helm issues?

Did you ever consider trying to sheet a smaller headsail inside the shrouds to point better?

I do have some weather helm, however not being an experienced sailor I was under the impression that some weather helm was desirable as in a severe gust / knockdown type of thing the boat would head herself up and take care of herself. I’ve only been knocked down once, and in truth she took care of herself, she turned herself into the wind and stood back up.

However it seems my weather helm is from my mainsail, as in I can reef it some and the helm is balanced, with it fully up I have some weather helm. Or I can loosen the sheet and reduce the power from the main.

I assumed incorrectly that going from a 110 to a 135 would offset the main and there would be reduced weather helm, but it made no difference at all, which surprised me.

So far as sheeting a smaller sail inside of the shrouds, no I have not tried that. I don’t see why it wouldn’t work, but honestly with my 110 Genoa I can sail so close to the wind that my VMG goes to pot, meaning that I believe it’s not ability to trim the sail in tighter that’s the limiting factor, but the boat itself.
I believe my keel type and depth as well as my windage and beam all work against me for sailing very close of the wind.
She just isn’t designed for it.

I could very well be wrong, but I believe I simply have the wrong boat for that job, and well, just learn to accept that, it’s not really all that limiting, I go to windward much better than some Lagoon Cats for instance, and yet no one seems to be overly concerned about that on them.
On edit
Interestingly even though I depower a sail some to correct the weather helm, I lose no speed in doing so, and usually she stands up some and doesn’t heel as much, although my boat heels very little as it is.
Assumption is any “Extra” power made by the sail is lost in the drag created by the rudder to correct for weather helm.

[hpeer]

A64,

Thanks very much for that post.

We too consider myself a novice sailor. I’ve a lot of miles but clearly have a ton to learn.

The Genisis of my questions is I’m trying to reduce weatherhelm enough to get the AP to work more frequently. But also because one day I was sailing under main and staysail fairly well balanced but slow, in about 15 knots, fairly sloppy waves. As soon as I rolled out some Yankee she picked up to 6 knots but also heeled and developed a distinct weatherhelm.

So that set me on this mission I’m on.

[a64pilot]

I broke out some of the bolt rope on my mainsail in high winds the other day, so that meant sailing on a beam reach in 20+ kt winds with just the Genoa. I’ve affected a crappy repair since then.
There was little if any weather or lee helm. Why I don’t know.
I’m surprised that your head sail when out will pull itself into the wind.

[a64pilot]

This article seems to jive with what happens on my boat. To induce weatherhelm a Genoa has have a large portion of its sail behind the mast
I guess my 135 isn’t big enough to have much behind the mast, it actually seems pretty balanced from a weatherhelm perspective
https://www.riggingdoctor.com/life-a...elm-and-genoas


Thinking about it, you would think that my code zero would produce huge amounts of weatherhelm as there is a large portion of it behind the mast.
But it doesn’t.

[hpeer]

A64,

That’s where we differ, I’m getting weatherhelm with the ~110 Yankee less than half deployed, with the foot still well ahead of the mast. Pronounced.


Breaking the bolt rope sounds like expensive no fun.

[roverhi]

I've only owned 3 full keel boat so not a lot of experience with different hulls but all developed weather helm as boat speed increased. If they were sailing well there was considerable weather helm. On one boat would have the helm hard over when it was exceeding theoretical hull speed. The weather helm is generated by the hull not sail configuration for the most part when speeds were within 75% or more of theoretical hull speed. If I was not feeling weather helm, sometimes extreme, the boat wasn't sailing to its potential. Hear people saying you have to balance the sails to reduce weather helm which to my experience isn't true. Reducing sail area will help some in reducing wx helm but really really penalizes boat speed in most cases if that is the only reason for doing it. Yes you should reduce sail, reef the main to counter overpowering/heeling of the boat. For most modern flat bottomed boats, heeling over 15-20 degrees really slows the boat down but it's not the resultant wx helm that's at fault. Older wine glass designs will tolerate a bit more heel to as much as 25 degrees and still sail optimally. All in all if the boat is heeling to the point of being uncomfortable it is not an efficient way to sail and reducing will result in boat speed increase but not because of reduced helm pressure. Should qualify comfortable heel as that's anything less than 20 degrees for me.

Have owned two fin keel boats. One had extreme helm control issues, so much so I seldom sailed with the main up in the prevailing blustery wind conditions. Even when sailing just under a headsail the boat would round up when hit with a gust and always had some amount of wx helm. The other has slight weather helm in most conditions with the optimum sail configuration. Even when screaming on a reach at near hull speed the helm is easily controlled and forces livable. Obviously it's hull design that makes the difference.

So expect some weather helm if you are going to be sailing near optimum potential. Reefing or striking the main can reduce weather helm but it's most likely the hull that's more the cause. If your autopilot can't handle the forces required to steer the boat, time to buy a more powerful actuator. Better yet get a pendulum servo self steering vane and let the wind and water do the work of steering the boat.

[hpeer]

Rover,

Thanks for the comments.

Here are some pics of her hull form, far from flat bottom, deep bilges.

I take it this is the kind of hull shape you are describing above. 20° of heel is about what I experience. But the Wife is pretty grumpy by then. AP gave up well before that.


I’m still feeling the Yankee is contributing excessively to heel for the power gained but I have more fiddling to do.

[hpeer]

Another thought gas entered my mind regarding the sail.

When you deploy a headsail (Yankee for me) from a roller furling ideally you should fill it out the entire way.

I read that if you reef the headsail then you can only effectively do so by about 25%, that will leave something like 65% of the sail area still up. Supposedly if you feed more the sail will be one “inefficient” or “ineffective” or similar adjectives.

My question is, What are the likely symptoms to be noticed if you were to roll the sail up say 50% leaving up say 30% of sail area? How would this “Inefficiency” manifest itself? Specifically would it introduce a lot of heel for the power added?

[a64pilot]

Originally Posted by hpeer

Another thought gas entered my mind regarding the sail.

When you deploy a headsail (Yankee for me) from a roller furling ideally you should fill it out the entire way.

I read that if you reef the headsail then you can only effectively do so by about 25%, that will leave something like 65% of the sail area still up. Supposedly if you feed more the sail will be one “inefficient” or “ineffective” or similar adjectives.

My question is, What are the likely symptoms to be noticed if you were to roll the sail up say 50% leaving up say 30% of sail area? How would this “Inefficiency” manifest itself? Specifically would it introduce a lot of heel for the power added?

It could but I believe it’s more of a sail shape issue than a loss of surface area, much furl and you lose the shape.
I believe also that by furling you’re moving the center of effort forward which should reduce weather helm or increase lee helm however you want to look at it.
I have the foam luff which is supposed to help with shape but I’ll only reef a little, any more and I just furl it, and leave the staysail out. I’ve never fueled the staysail.

But to continue with weather helm, the staysail increases the surface area in front of the mast, and ought to help reduce weatherhelm when it and the Genoa are both up. On mine, maybe. If it does I’m just not a good enough helmsman to notice to be honest.