Less Conventional Approaches to Controlling Yawing

[thinwater]

An anchoring thread, but not an anchor thread at least....

Let's skip past...

• Heavy chain or kellet (stops working when it blows hard anyway)
• Riding sail (adds some wind load, but less than yawing)
• Hammerlock mooring (effectiveness reduced when it blows hard--more scope on hammerlock?)
• Dodger and davits probably help

To perhaps less common approaches...

• Lift the rudder (if applicable)
• Take the dinghy off the foredeck
• Lower furled reachers (big impact if on bowsprit)
• Non-stretch bridle for nylon rodes (yes, this actually helps, but don't try it with chain)

And on to what I have missed...

• Adding a drogue to the chain? Doesn't seem like it moves fast enough for this to do much, though it would move the COE.
• Other?

[SailFastTri]

You skipped: Bridle with uneven legs, with longer leg attached amidships (on a monohull) so the boat is affixed on an angle to the wind.

But you have a cat, so why does your boat yaw with a bridle? Maybe your bridle legs are too short, or maybe your attachment points aren't as wide as your beam? Make each of your bridle legs 2x to 3x the beam, and move attachment points outboard (if not already maximized). That should control it.

[thinwater]

Originally Posted by SailFastTri

You skipped: Bridle with uneven legs, with longer leg attached amidships (on a monohull) so the boat is affixed on an angle to the wind.

But you have a cat, so why does your boat yaw with a bridle? Maybe your bridle legs are too short, or maybe your attachment points aren't as wide as your beam? Make each of your bridle legs 2x to 3x the beam, and move attachment points outboard (if not already maximized). That should control it.

Yup, a bridle can help. I've used one every time for 25 years. So obvious I left it off. I did hint at it in the last item (non-stretch bridle for nylon rode), but left off the most basic.

• 2:1 bridle for multis
• Uneven bridle for monos

I didn't say I was having a problem, either with my former cat or my current tri.

One problem with long bridles on multis with chain rode is that if you anchor shallow the bridle can easily touch the bottom. I snagged a log that way once. The answer is to shorten up to about 1:1 in light winds. It is still enough in those conditions.

[Erik de Jong]

Originally Posted by thinwater

Adding a drogue to the chain? Doesn't seem like it moves fast enough for this to do much, though it would move the COE.

Works fantastic! Some other cruiser told me once but I was very skeptical, I was wrong, boy does it make a difference!

[thinwater]

Originally Posted by Erik de Jong

Works fantastic! Some other cruiser told me once but I was very skeptical, I was wrong, boy does it make a difference!

Please share the details. Where it is rigged, what type, what size, and how it is rigged.

[Erik de Jong]

I have a snubber that goes with a standard chainhook on the anchor chain. The cone comes off a series drogue and I can snap the single cone with a snap-shackle to the chain hook of the snubber. I let enough chain out so that the hook is roughly 3-4 feet underwater.

The cone is approximately 14" in diameter and 18-20" long.

Be aware that you will yaw a lot less, which could become problematic on a tight anchorage with other boats, they generally Yaw somewhat simultaneously and you'll be the only one who will almost not yaw.

I did anchor once in a fairly large chop (2+ feet) in that case I do not recommend using it as the strain on the bowroller becomes enormous due to the continuous vertical movement.

[thinwater]

Originally Posted by Erik de Jong

I have a snubber that goes with a standard chainhook on the anchor chain. The cone comes off a series drogue and I can snap the single cone with a snap-shackle to the chain hook of the snubber. I let enough chain out so that the hook is roughly 3-4 feet underwater.

The cone is approximately 14" in diameter and 18-20" long.

Be aware that you will yaw a lot less, which could become problematic on a tight anchorage with other boats, they generally Yaw somewhat simultaneously and you'll be the only one who will almost not yaw.

I did anchor once in a fairly large chop (2+ feet) in that case I do not recommend using it as the strain on the bowroller becomes enormous due to the continuous vertical movement.

Any weight on the drogue, to keep it from wrapping around the rode?

That is a lot larger than JSD cones (about x more area). Is that what your drogue is based on? I've always wondered about alternate designs, but very few try anything different.

In that case, I have a variety of drogues to test out. In order to get my tri to yaw I intentionally don't use a bridle; that will get her dancing.

[conachair]

Originally Posted by Erik de Jong

I have a snubber that goes with a standard chainhook on the anchor chain. The cone comes off a serie.......

Thanks, interesting. Been thinking about this for a while, given that the energy to get rid off is proportional to speed squared when the boat is moving on the hook slowing the boat veering around in a blow could significantly reduce load on the hook. On paper anyway....

[Snowpetrel]

I've used a big round inflable fender tied to the chain to create drag. Seemed to help. In the gusts it would get pulled underwater creating significant drag.

A tyre tied onto the chain should work well. Prehaps the ultimate would be a short series drogue snubber?

A few other tricks are to drop an anchor at very short scope under the bow, or off at the extreme of one sheer/yaw. Or even simpler drop a big bight of chain behind the snubber so it drags on the seabed slowing and damping any yaw. I guess this could work in deep water using just the drag in water.

I think the drag device at the bow has to take a lot of energy out of the anchoring system and dissipate it into the water, meaning the anchor and snubber have to do much less work.

[thinwater]

Originally Posted by Snowpetrel

I've used a big round inflable fender tied to the chain to create drag. Seemed to help. In the gusts it would get pulled underwater creating significant drag. That seems rational. It would reduce scope a little, but it would apply drag a the right time. No inflation time. Wouldn't do much in lighter winds, but the chain should help then. Wouldn't do much in 15-20 knots. But above that it should work.

A tyre tied onto the chain should work well. Prehaps the ultimate would be a short series drogue snubber? I don't think a series drogue is the answer. It would take too long to pull in line.

A few other tricks are to drop an anchor at very short scope under the bow (this is a hammerlock mooring--works well), or off at the extreme of one sheer/yaw. Or even simpler drop a big bight of chain behind the snubber so it drags on the seabed slowing and damping any yaw. I guess this could work in deep water using just the drag in water.

I think the drag device at the bow has to take a lot of energy out of the anchoring system and dissipate it into the water, meaning the anchor and snubber have to do much less work. I don't think this is about energy absorption, it's about moving the underwater COE forward. This is why it should be something that "catches" immediately. Moderate yawing does not typically unset the anchor, but it can cause it to slowly walk, as it shuffles, particularly in loose sand. The increase in force is mostly due to the wind hitting the boat from the side, not the yawing per se. But that can double the force.

A few thoughts above. Good ideas.

[waterman46]

I advise against the idea of dragging a length of chain over the bottom day and night. Lots of wear on the galvanizing of the chain, and in some areas you'd be adding to destruction of marine life and habitat (more than just your normal anchor chain). And when the wind and/or current switches and your boat passes back over your anchor on it's way to the new position, you are likely to foul your anchor with the dragging chain.

Next chance I have, I will try using a makeshift drogue (old sailbag with a heavy solid SS wire in place of the drawstring) attached to the crown of my second anchor and lowered about 1 meter below the surface off the bow roller. That way it's not likely to foul my anchor chain and should have better leverage on the bow motion than if attached some point down the active anchor's chain.

[guyrj33]

I tied a bucket to a rope and tied that to the bow of our Pearson 10M, solved the yawing we were experiencing in 30-40kt winds.

[quandary]

The basic cause of the yawing is often because the windage on the rig and hull is trying to turn the boat around to face the stern into the wind. On a modern sloop, the rig (and hence wind resistance) is well forward and "upwind" at anchor from the bow so the most neutral equilibrium position for the boat would be if it is anchored from the stern. The wind 'drag' on the boat if anchored from the stern would then be at the "downwind" end and the boat will lie quietly without any yawing or "horsing" at anchor.
Of course, the ground tackle is designed for use from the bow so the only answer, if you don't want to 'fight' the yawing forces, is to increase the wind resistance at the stern end to be more than at the bow end so that the boat naturally "feather" into the wind. A riding sail as far aft as possible has a similar effect as it acts like an air rudder that keeps the boat facing head to wind and prevents it from swinging.
It is about "feathering" the boat into the wind, not using brute force to counteract the boats efforts to turn itself around to get into a neutral "feathered" position. Achieving this "feathered" position will dramatically reduce and minimise the forces on the ground tackle as the boat will lie quietly into wind without being jerked from one tack to the other as it yaws back and forth.

[thinwater]

Yawing: swinging side-to-side.
Horsing: fore-aft motion. Not a synonym for yawing (ref. Coast Guard and US Navy studies).
Hobby Horsing: up and down at the bow, AKA pitching.
Sailing at Anchor: generally yawing, though horsing contributes.

Quandry: I think it is a mistake or at least an exaggeration to characterize drogues etc. as brute force. In fact, the force on these drogues is typically a few dozen pounds a most, no more. That is all a 10-20 pound anchor at super short scope exerts (I've done the testing), and yet it works by convincing the boat to feather. They are effective because they move the underwater center of effort forward. Thus, they are a another type of "feathering" method. A centerboard at the bow would probably help, but this is impractical.

[wsmurdoch]

I have a 32" cone drogue and have deployed it off the bow tied to the anchor chain below the water surface and to the stern 30" tied above the water surface on a short line so that it always remained submerged. The measured reduction in yawing was less than using a riding sail. See http://www.cruisersforum.com/forums/...ml#post2407522

That said, the drogue is great at pulling me away from mooring balls that always beat against the hull of the boat while we are sleeping in the vee berth. Tie it to the stern, throw it over the side, and you can sleep the night away in St Augustine. The current will pull us away from the mooring ball.