Weaving Back & Forth at Anchor

[nelson.peter]

We have a Jeanneau Sun Odyssey 45.2 that weaves back and forth when at anchor. If we could stay inside the tabs of the talk (+/- 30 deg. off center), I'd be fine. But our boat veers as much as 40-50 deg. It is uncomfortable as well as increases the chance of dragging anchor as the force of the wind strikes the hull. It seems to veer more than other boats. I am trying to figure out why so I can come up with a solution.

It seems to be sailing on its foil (keel) over the wind-induced surface current. I've tried locking the wheel to either side with the boom (and stack pack) secured to one side of the boat. I have tried going off the bow roller as well as off the forward cleat scupper, to no avail. We've tried tying a bucket off the stern to slow its swing! Nothing has worked.

I am not interested in building a steadying sail or dropping a stern lunch hook.

Am I missing something simple here? Or is there a deeper issue I am not seeing? Your help is appreciated. Thanks.

[Stillraining]

Buy a Ketch..... its already built........sorry I'm no help I realize that.

[MarkJ]

It really doesn't matter.

I tried to use twin snubbers set back as far as I could then checked from the beach and its swing was still the same. Tried anchor weights too. I just gave up worring about it.

I KNOW it doesn't affect the anchor as the scope you would have laid out isnt swinging, just the boat.

Find a nice shallow clear patch of water to anchor in and try some trick but you will see its not affecting the anchor itself


You can buy a samll riding sail... buts that is just going to add weight to your anchor!

[fishfinder]

My understanding is most modern sailboats, under bare poles and not making way in the water (like at anchor), will naturally veer away from the wind. My boat settles at I would guess 60 degrees off the wind under bare poles. This has to do with the way the wind hits the boat and rigging ... modern boats have masts forward of the boat's center, and bulky furled headsails on the bow. These things act as little sails, and the wind pushes on them -- in turn pushing the bow downwind because there is more wind resistance towards the bow than towards the stern. At anchor the boat is being pulled by opposing forces: the boat wants to settle bow off the wind, but the anchor line is pulling the bow forward into the wind. So there is this constant play between these 2 forces resulting in sailing at anchor.

To fix this you could add wind resistance to the stern (anchor riding sail) which you already said you don't want to do. You could try decreasing the resistance on the bow say by taking down the furled headsail, which may help a limited amount. Or you could try anchoring from the stern which I've done, it helps a little but you get funny looks.

I fought this at first but now most of the time I just live with the sailing at anchor, nice to get a change of scenery every couple minutes.

[GordMay]

ANCHOR SPRING LINES:

Often, you anchor where the Wind and the Water work at cross-purposes. Some anchorages may have a strong current running through them, or sometimes experience a strong surge or groundswell. Even a smaller current or surge can set your boat to rocking - and you know how uncomfortable a rolling boat can be. A really fast current or big swell can make the harbor untenable.

Fortunately, there's an easy way to alleviate all that by the use of a forward quarter spring line to the anchor rode, a technique called "springing the rode".

To understand how Anchor Spring Lines work, it will be helpful to visualize the conditions that call for it. Suppose you're anchored in a harbor where the wind is blowing from the east. Lying to her anchor, your boat will point east into the wind. Now, suppose there's a surge rolling into the harbor from the north (or a current running South). It could be a ground swell generated by some distant storm, or just a remnant of seas outside the harbor bending around the headland. Whatever the source, waves from the north will strike your boat on the port beam and she'll rock-n-roll.

But if the vessel were turned 90 Degrees to port, pointed into the waves rather than into the wind, the effect would be a much reduced, fore-and-aft motion, i.e., pitching instead of rolling. By comparison, pitching in these circumstances is hardly noticeable unless it becomes really extreme. So, how best to point the boat into the surge is the key to comfort in this harbor.

Most sailors will immediately think of setting a second anchor from the stern. In this scenario of an east wind and northerly wave action, the stern anchor would be set well out to the southeast. Then, by hauling in on the rode aft the boat can be made to face north. There's nothing really wrong with this solution, except that
(a) It is more work than necessary, carrying out and later retrieving the second hook, and
(b) The boat can no longer swing with other boats nearby that are laying to only one anchor. This may create spacing problems if the wind shifts.
(c) You are constrained by two anchors, which would delay your departure in the event circumstances necessitate a rapid escape.

A much easier, more efficient solution can be accomplished using the bow anchor that is already set and a spring line. Simply tie a long dock line to the bow anchor's rode or chain at the bow of your boat. A roving hitch works well for this. Lead the line aft alongside the hull to (in this case) the starboard cockpit sheet winch. On a center cockpit boat it would be best to pass the line through a stern quarter turning block before leading it to the winch. Check that the line is running outboard of the bow pulpit, stanchions, and shrouds.

Next, pay out the anchor rode, about 1/3 to 1/2 of a boat length. Finally, take up on the spring line until there's roughly equal pull on the rode and the spring. The boat will swing broadside to the wind and will face the swell. It's as simple as one-two-three!

Our example illustrates a perpendicular wave (or current) to wind angle. But you can adjust the vessel's heading to suit other conditions: If the waves are forward of the beam, feed out less of the rode and/or take in less on the spring line. To head her further off, slack the anchor rode more and/or haul in some more on the spring. A little experimentation and you'll easily master this useful technique.

Here are a few other pointers:

If the waves are abaft the beam it may be equally comfortable to lay your boat's stern to face them rather than the bow. This will require less line adjustment than swinging the bow all the way around.

Remember: To turn the bow to port, use a starboard forward quarter spring line; to turn to starboard, use a port spring.

If the wind gets to blowing harder and you feel uneasy about the strain your boat's beam-on position is putting on the anchor, you can instantly return to the normal anchor mode - bow to the wind - just by releasing the spring line. The boat will quickly swing to the breeze. The spring line can be recovered later when you weigh anchor.

This technique does rely on a fairly consistent breeze. If the wind shifts, you'll have to readjust the boat's angle. If the breeze dies altogether, deploying a stern anchor may be the only way to hold your boat end-on to the waves.

[nelson.peter]

Learn something every day!! Thanks GordMay for the little primer on anchor springs. I wonder if I could set a spring such that the boat is cocked to one side and only slightly into the breeze -- say 30 deg.? That would keep it from swaying. I might try it in less than the 35-40k we had yesterday. (We're in the middle of what I call the Aegean Wind Tunnel!)

I talked to a couple from Britain on the bus today and they have a steadying sail. So maybe I'll come around to making one of those. I have a roll of Sunbrella I could possibly turn into a small sail. Fly it off either the topping lift or rig something off the backstays. Thanks, Fishfinder, for your comments as well.

[Vasco]

My CS36M skates like crazy at anchor when it's blowing. My B393 does it a lot less. I think it's from the placement of the keel. The keel is shorter and more forward on the CS. The only solution to this is to place two bow anchors in a "V" and that's what I do to prevent the skating. A riding sail doesn't work. I have noticed quite a few modern boats skate so badly that it scares others in the anchorage, some big Hunters and Saga 43's are bad. Of course full or long keel boats just sit there. So I don't think it's the superstructure, it's the keel.

[Oceansandmts]

A steadying, or riding, sail will make a big difference, I use it all the time. I think all chain or a second anchor off the bow on almost no scope will stop a lot of the movement of the boat but may not stop the tacking back and forth. Without the riding sail on a rope-chain rode we used to tack back and forth, covering a lot of real estate as we sailed to the end of 7 to 1 scope on port tack, tacked and did the same on starboard. The riding sail stops 90% of this and only takes a couple minutes to hoist and set. I have not tried one, but I understand a wedge, or delta, riding sail is most effective.

[cat man do]

Damn Multihulls

Didn't anyone tell you they always veer at anchor?

[David M]

Run your anchor rode aft and attach it not at the bow where it normally attaches to the boat but a distance back. Experiment with that distance.

[swagman]

Unless I got it wrong a Jenneau 45 is not a multihull! And can advise hanging objects off sternsimply will not work.

Anyway, I understand your problem as we had same with our high freeboard Hanse 461. For a year it was embarrassing when the wind came up and we hunted back and forth looking as if we were about to ram fellow boats at anchor.

Problem was solved not by a riding sail - or adjusting angles (did try but not worked for us) - but by simply hanging a drogue from the anchor chain just below the waterline.

It works.

Now not just for me, but all other 461 owners who copied the idea. I am sure it would work for a Jenneau also.

Remember attach it to the chain and not the bow or the boat. You can see how it works in action.

Wind finds one side or other of bow - bow starts to swing away.
Without drougue it goes quicker - leaving whole side presented to wind - which causes yacht to sail to end of scope - snatch up - and as you know, back she comes to repeat the ride.
With drogue it blows off slower - usually allowing stern to 'catch up' in seconds and fall in alignment behind your bow. Boat moves to gust, but goes nowhere.

If you doubt me try it hanging a couple of buckets - remember from chain under waterline and not the boat - and I think you'll be back to say 'wow'. It is that simple.

Cheers
JOHN

[Stillraining]

Two great Ideas ffom Gord and Swag...Thanks guys..great stuff...by the way Swag whats the specs of your drouge?

[rtbates]

Just anchor by the stern...Jordan Series Drogue - Mooring and Anchoring

Or trade her in for a ketch, schooner, or some rig that has wind resistance toward the aft end.

[Bash]

...one thing that helped my boat remarkably was installing weather cloths around the cockpit. I'm guessing they function like a riding sail?

[swagman]

Our drogue came from Plastimo - blue fabric maybe 1 metre long, mouth maybe half that. We clip it on with stainless (captive pin) shackle.

BTW - for those who rate riding sails, go try one out in a 60+ knot blow and let us all know if this added windage works OK for you.

Good luck with the drogue trial - and be sure to let everyone know the outcomes.

JOHN