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Hi all,

I have a 35 foot sloop that likes to yaw under anchor when windy. we have 100 feet of chain combined with rope as our rode. I've been told that using a bridle and/or snubber would help minimize the yaw as well as keep the boat settled under anchor, as well as taking the shock off the chain. I've always felt that this wasn't necessary as the rope is essentially a snubber. I'm curious what advice there is out there about this and what others do in similar situations. And if you do use a snubber and bridle how to you attach to the rope? Thanks in advance for your wisdom!
 

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You only need a snub line if you are sitting on chain. One would hope the line on your anchor rode is nylon, so it has lots of stretch, therefore a snub is useless. I've not seen any value in a bridle to minimize yawing, they are mostly used on boats with bobstays.
 

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Yawing is not swing .


Is that 100 ft chain and then the rode.
What’s the rode made off (3 strand most common) ?

Let’s look at how you anchor. Rode is going through the anchor roller with bale or through the bow chock and then to the cleat correct? How much rode do you put out in 10 ft of water, no tide change?

The answer if you want 7:1 scope is 10 + your freeboard ( or the distance from anchor roller to the water- usually 5
ft) so that’s 15 X 7 or 105 ft. I know some anchors don’t require 7:1 but your bow keeps pulling down . Tide change changes this equation also. Many people forget to add the freeboard into the equation.

Your rope rode should be a good enough shock absorber. You can of course wrap you line rode around a snubber to help also.
 

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You need to determine the cause of the boat's motion at anchor. It could be restless for a number of reasons... such as high free board (more windage), small area of keel, forward stepped mast moving the center of effort forward or a combination of the above. There's little you can do about the features of the boat's design causing it to be restless. What happens is the bow "catches" wind and is pushed to leeward.... then the lee side of the boat sees the wind and the stern gets pushed to leeward making the bow pass through the eye of the wind catching the wind now on the opposite site... and this process repeats.

The best cures for this are a riding sail to keep the boat weather-cocked... like a wind vane pointing at the eye of the wind.... or rig a line to the anchor to a cleat on one side to prevent the boat from "pivoting" thru the eye of the wind. Rising sails are very small, easy to stow and deploy aft on the backstay or topping lift. A ketch or yawl will leave the missen sail up for this purpose.

A bridal will not prevent yawing.
 

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You can try a riding or anchor sail, but I suggest just getting used to it. It's inherent in a lot of boat, especially those with higher topside and/or large enclosures.
 

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Yawing is not swing .


Is that 100 ft chain and then the rode.
What’s the rode made off (3 strand most common) ?

Let’s look at how you anchor. Rode is going through the anchor roller with bale or through the bow chock and then to the cleat correct? How much rode do you put out in 10 ft of water, no tide change?

The answer if you want 7:1 scope is 10 + your freeboard ( or the distance from anchor roller to the water- usually 5
ft) so that’s 15 X 7 or 105 ft. I know some anchors don’t require 7:1 but your bow keeps pulling down . Tide change changes this equation also. Many people forget to add the freeboard into the equation.

Your rope rode should be a good enough shock absorber. You can of course wrap you line rode around a snubber to help also.
What is the difference, in your definition, between swing and yawing? I'm pretty sure there is no generally accepted distinction. Not a challenge, but rather an honest question.
 

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What is the difference, in your definition, between swing and yawing? I'm pretty sure there is no generally accepted distinction. Not a challenge, but rather an honest question.
Yaw is rotation... about a point within the boat's length, Swinging is a rotation about the anchor location. A boat can both swing and yaw.
 

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Rope rode vs. snubber. It is correct that you do not need a snubber when rope is deployed, with one important caveat; you must NEVER deploy less than 30 feet of rope. If only 5-15 feet of rope are out, that is not enough to easily absorb the wave and gust energy and the rope can be over worked. Combination rodes have failed when too little rope was deployed, and example of which was written up in Sail Mag a few years ago. Rope is limited both in strength and also energy/foot that it can absorb. You need a minimum number of feet.

A riding sail can help, but they are not all equal. Riding Sail Testing

A bridle really helps multihulls, but less so on monohulls. The bow angle is too narrow.

Chafe gear is a good idea. Make certain the roller area is very smooth and that the rope cannot jump out.

Other options include:
  • Reducing windage forward. Is there a dinghy on the bow? Remove it.
  • Hammer lock. Lower a second anchor from the bow at very short scope (1.5:1) that just drags.
  • Hang a drogue from the rode, near the bow. A stack of Rocker Stoppers or a 2' fishing drogue. This will not stop yawing, but it will slow it way down.
  • Two anchors can be used a number of ways, but there are other down sides (complexity, swing different from other boats) that make this less desirable.
  • Kicking the anchor to one side can help. Not always.
Good anchoring is both simple and devilishly complicated. Rigging Modern Anchors
 

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A vessel's motion rotating about the vertical axis, so the bow yaws from side to side; a characteristic of unsteadiness.

Cats don't yaw as much because the attachments are so wide apart.

All "anything" is not equal...

The most reliable way to reduce yawing at anchor is to deploy a proper sized and placed riding sail.
 

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While yaw and swinging are different, you can't swing without first yawing. The reality is that most modern boats will 'kite' on the anchor. The tendency to kite is a product of a lot of yacht design factors that make modern boats sail better and easier to handle, but at the price of kiting more extremely. For what is worth freeboard generally is not all that significant factor since the rig size and position has a much greater impact on how a boat behaves on the anchor. The amount that a boat kites and speed at which it swings are driven by the design of the boat itself and the techniques that work best to minimize kiting would therefore also be a product of the boat itself.

Having owned a number of boats that kite wildly and experimented with all kinds of techniques, I will suggest that none work all that perfectly on a monohull that wants to kite when on the hook. In the order of effectiveness,
1) Using a kellet (a heavy weight hung from the anchor line) on a long enough leash to drag on the bottom. That works in almost all conditions.
2) Tying a line onto the anchor rode with a rolling hitch and leading the line aft to the cockpit winches so that boat sits at an angle to the wind. (This works pretty well but if the bow manages to pass through the wind due to current or a windshift, the aft run line can end up snagged on the keel. Don't ask me how I know.)
3) Rigging a riding sail helps in some conditions but with most modern boats, it can also make matters much worse in a stronger breeze since the overall rig is enough to cause the boat to yaw despite the riding sail. Once the riding sail is across the wind it helps accelerate the speed of the boat. Again don't ask me how I know except that I will say that my prior boat, a Laser 28 could hit 2 knots with the riding sail rigged and actually get to windward of the anchor in a stiff breeze.It rode much more quietly without the riding sail. Reportedly the 'delta' style riding sails are more effective than the traditional flat sails but I have not tried one of those. A large aft cockpit enclosure can act as an unintentional delta riding sail.
4). Although counter-intuitive, anchoring from the stern does not help much either. I tried leading my anchor rode to stern and actually using a bridle to center it after tying off to one side did not work. What I found was that it took a little while for the boat to start to swing, but once it did, the canard placement of the rudder means that the boat will veer less as it picks up speed and so the swings get progressively wider.

Jeff
 

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I almost always tie my snubbers in a bridle, and I believe it does help reduce yawing or swinging or kiting or whatever you want to call it. My boat does not sail around nearly as much as most others at anchor. Of course, this has as much to do with my boat's design as the bridle, but when I've tested it I concluded the bridle did help.

You can rig a bridle to rope rode, although this is pretty rare. When I had my ketch I would hoist the mizzen a bit to create a riding sail, which did work somewhat. Never tried the other suggestions (no need), but have heard they work to different degrees.

All depends on your boat and how it's configured. Experiment to see what works.
 

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While yaw and swinging are different, you can't swing without first yawing. The reality is that most modern boats will 'kite' on the anchor. The tendency to kite is a product of a lot of yacht design factors that make modern boats sail better and easier to handle, but at the price of kiting more extremely. For what is worth freeboard generally is not all that significant factor since the rig size and position has a much greater impact on how a boat behaves on the anchor. The amount that a boat kites and speed at which it swings are driven by the design of the boat itself and the techniques that work best to minimize kiting would therefore also be a product of the boat itself.

Having owned a number of boats that kite wildly and experimented with all kinds of techniques, I will suggest that none work all that perfectly on a monohull that wants to kite when on the hook. In the order of effectiveness,
1) Using a kellet (a heavy weight hung from the anchor line) on a long enough leash to drag on the bottom. That works in almost all conditions.
2) Tying a line onto the anchor rode with a rolling hitch and leading the line aft to the cockpit winches so that boat sits at an angle to the wind. (This works pretty well but if the bow manages to pass through the wind due to current or a windshift, the aft run line can end up snagged on the keel. Don't ask me how I know.)
3) Rigging a riding sail helps in some conditions but with most modern boats, it can also make matters much worse in a stronger breeze since the overall rig is enough to cause the boat to yaw despite the riding sail. Once the riding sail is across the wind it helps accelerate the speed of the boat. Again don't ask me how I know except that I will say that my prior boat, a Laser 28 could hit 2 knots with the riding sail rigged and actually get to windward of the anchor in a stiff breeze.It rode much more quietly without the riding sail. Reportedly the 'delta' style riding sails are more effective than the traditional flat sails but I have not tried one of those. A large aft cockpit enclosure can act as an unintentional delta riding sail.
4). Although counter-intuitive, anchoring from the stern does not help much either. I tried leading my anchor rode to stern and actually using a bridle to center it after tying off to one side did not work. What I found was that it took a little while for the boat to start to swing, but once it did, the canard placement of the rudder means that the boat will veer less as it picks up speed and so the swings get progressively wider.

Jeff
As you have experience with different designs and attempted solutions this post is a good one. My experience is with my hull which has high free board... a fractional rig with mast above the forward end of the keel which is a deep fin. The boat yaws on anchor in winds above 10 knots or so. I use all chain and a single line snubber with a mooring compensator to further absorb shock loads. I use a fairly large and very flat cut (no draft) riding sail attached to the boom end which I restrained with lines to port and stbd cleats. I find this quite effective. and it even limits swing as well as yawing. I can't comment on other boats.
 

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Yaw is rotation... about a point within the boat's length, Swinging is a rotation about the anchor location. A boat can both swing and yaw.
OK, that would be the dictionary difference.

But they always occur together. Yaw causes swing. If the bow is so tightly secured that swing is not induced by yaw (V-anchor, for example), the boat won't yaw either, because it cannot fall off. It is falling off that allows yawing. So while the dictionary defines them separatly, I've have never seen one independent of the other. I thought that might be what you meant.
 

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A vessel's motion rotating about the vertical axis, so the bow yaws from side to side; a characteristic of unsteadiness.

Cats don't yaw as much because the attachments are so wide apart.

All "anything" is not equal...

The most reliable way to reduce yawing at anchor is to deploy a proper sized and placed riding sail.
This is funny--the last two sentences are in direct conflict.

The most reliable way to reduce yawing varies between boats, but almost certainly is to deploy two anchors in a V. I didn't say it was the "best" method, because like "fair," it is a made up condition unless the criteria for evaluation are narrowly defined. And not all riding sails are equal--effectiveness varies from minimal to excellent.... depending on the boat.
 

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One parting thought. Unless a strong storm or squall is coming, the best method is often the easiest method.

For my boats (multihulls)...

  • Bridle is the go-to method, but that is because I have a lot of beam. On a cat it is also the easiest method. On a tri, however, there are complications that some times make monohull methods easier. But for a squal it will be the bridle.
  • Chain kellet is next easiest. Just a loop of chain attached to the rode. It plays right over the roller, easy peasy. But not good once the wind it up. Works best in shallower water. A solid kellet is a pain.
  • Rudder up. If the rudder lifts, lift it.
  • Board down. Do not lift daggerboards or centerboards.
  • V-riding sail. I like the over-the-boom style, as they are far more effective and single panel sails, are easier to rig in a blow, can stand more wind, and give me some shade.
  • Hammer lock. If you have two anchors on the bow this is dead easy and very effective. But it's not good on sensitive bottoms and it alters the swing with shifts (yup Chef, that is a different use of the word swing--I forgot). But very effective.
  • V-anchors. Generally only if the bottom is soupy mud and holding is stretchy. Also if there is a reason to tightly control swing. Not too hard if the second rode is rope. But I'd need a reason. I've done this many times when pull-testing anchors off the stern with the winches, to make certain the boat would not move.
 

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  • V-riding sail. I like the over-the-boom style, as they are far more effective and single panel sails, are easier to rig in a blow, can stand more wind, and give me some shade.
Everything you say is great. I have a question about the quoted point, though. I read the tests of V-shaped riding sails and they usually come out favorably over single-panel sails as far as effectiveness to limit swing (or yaw or whatever) is concerned.

But they also must increase the overall windage, and thus the mean load on the anchor tackle. Is that an issue, or is this effect over-compensated by the smaller dynamic loads due to lowered swing/motion? Is there any data on that?
 

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I feel lucky

Haleakula only sails when I want her to ( anchor up)😀

I never realized it’s such a common problem , but our anchorages aren’t crowded so I don’t usually worry about other boats 😄
 

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This is funny--the last two sentences are in direct conflict.

The most reliable way to reduce yawing varies between boats, but almost certainly is to deploy two anchors in a V. I didn't say it was the "best" method, because like "fair," it is a made up condition unless the criteria for evaluation are narrowly defined. And not all riding sails are equal--effectiveness varies from minimal to excellent.... depending on the boat.
Not that limits swinging and keeps you in the same spot.
 

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Everything you say is great. I have a question about the quoted point, though. I read the tests of V-shaped riding sails and they usually come out favorably over single-panel sails as far as effectiveness to limit swing (or yaw or whatever) is concerned.

But they also must increase the overall windage, and thus the mean load on the anchor tackle. Is that an issue, or is this effect over-compensated by the smaller dynamic loads due to lowered swing/motion? Is there any data on that?
A perceptive question.

Yes, they do increase windage, but only a small amount compared to the windage reduction from keeping the boat better aligned. Even more importantly, perhaps, is that the anchor is not pulled from side to side. The increase is about 5-15% and the reduction in total windage is typically 25-50%. Lot of variables, including how much the boat was yawing to begin with.
PS review

I've long wondered if it would make sense to design an awning that was both shade and riding sail. It would, but I seldom use an awning with my current boat.
 
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