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jfjharry · 26-06-2019, 04:29

New to catamaran cruising and I have a 38' catamaran with mini keels. I've been in a few current flow opposite wind situations where the boat is continually doing nearly 360's, forced over the anchor and bridle, then the bridle actually pushes on the Screecher stays. I'd like to know from more experienced sailors what they have done to limit this happening.

**tkeithlu** · 26-06-2019, 05:26

I think you're saying that the wind in one direction pretty well balances the current in the other, so you've got a fight going between the two. Can you reduce one or the other, such that the stronger then "wins?" With keels rather than centerboards, reducing the effect of current may not include many options. Reducing windage might mean putting the kayak flat on the deck, dropping the gas cans down to the swim platform, and a bunch of other stuff individual to your boat.

Or, increase one, by for example trailing a drogue.

**GordMay** · 26-06-2019, 05:41

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.

**GordMay** · 26-06-2019, 07:11

mikereed100 · 26-06-2019, 07:45

That is a fairly common situation. I have been using Gord's solution for decades now, the last time being the night before last. It works well, but the fly in the ointment is that at some point the wind or the current will die or switch, rendering the spring line ineffective or, worse, under the boat wrapped around the keel or rudder. A stern anchor is the surest solution but can be an annoyance. Also, if the other boats in the anchorage are not using stern anchors as well, this is not an option. Even without a stern anchor each boat will behave differently depending on windage and bottom configuration, creating what they refer to in Mexico as the "La Paz Walze", in which every boat in the anchorage is marching to the beat of a different drummer.

So what do you do? If I can get away with it I will set a stern anchor. It helps if you have set your boat up so that you can do this without deploying the dinghy. If there are other boats around swinging on one hook so that a stern anchor is not an option I will often use a springline as described, expecting that at some point I will have to remove it. The other, and sometimes best, option is to simply leave a lot of room between yourself and the other boats and put up with it.

**StuM** · 26-06-2019, 15:34

Quote:

Originally Posted by GordMay

ANCHOR SPRING LINES:

Often, you anchor where the Wind and the Water work at cross-purposes.
.

Good info but irrelevant to the question.

Multihull forum, OP has a 38ft cat. It's not surge and rolling he's concerned about it's current v wind and turning about the anchor.

I'm sure the's on a bridle already

Dave_S · 26-06-2019, 20:51

When near other boats try to work with the tide, most boats do and only swing when there is very little current or a lot of wind. If you have a choice of boat to park near, try to pick one similar to you, it is more likely to behave like you. Cat next to cat, light next to light, keel with keel etc...

Regardless, in the last and first 1 or so hours of tide, boats usually break away from the force of the current at different times.

You can create some drag, a bucket or two tied short out the back might be all you need.

If you have lots of room point into the wind, much better out back and the rigging is quieter but if your still doing circuits around the anchor drop the buckets in.

Sojourner · 27-06-2019, 00:10

I don't have a solution for this beyond what the others said: increase or decrease one force until it wins.

But I do have a tip... This sort of happened to our monohull a few weeks ago, and it wasnt a problem....anchored off for a week or more, light winds and cross current turning the boat around and around. We have a beefy rocna, usually set it and forget it. But the soil was volcanic, even backing down it didn't set deeply, and after a few days of turning on winds too light to fully pull straight out/turn the anchor on the chain we set, the rode was encircling the partially protruding anchor at least three times when I first checked it. Would take much imagination to think of a windier day coming along and unhooking that great anchor and dragging our butts onto the rocks.

We pulled up 30m of rode, dropped it back while motoring astern, and she was good for another two or three days. But I visually checked it every time. My advice is, regardless of what you do to stabilize the boat, to not forget to dive your anchor regularly when conditions are like that.

mikedefieslife · 27-06-2019, 00:47

Tide or current is almost always more powerful than the wind. In one of my last anchorages less than 2knts of current easily over powered over 20knts + of wind. So far I've never found it an issue, since you want to be facing the current.

With a cat if you want to face swell (which is of course something different from tide/current), then you don't even need a spring line. If you bridal is long enough just remove it from one of the cleats and move that aft, either to a midships (if strong enough) or a stern cleat.

**JPA Cate** · 27-06-2019, 01:26

For multis, a small drogue off the stern will hold them bows into the current. And they will swing with the keel boats.

It will depend on the anchorage whether the boat is more comfy with the bows into the WIND instead. If so, then a spring to the anchor line bridle can help, as long as the wind is expected to stay the same for the night. Otherwise, you may be better off to twitch a bit, and let your body know it's okay. Most people get accustomed to their boats' motion.

Ann

44'cruisingcat · 27-06-2019, 14:15

A nice thing about having daggerboards and kick up rudders- we can adjust the amount of tide effect on our boat, and can usually point into the wind.

But on boats that can't do this, as said before, some kind of drogue can keep you pointing at the tide. Put it on a short bridle between the transoms to prevent it from wrapping itself round rudders, saildrives etc.

A stern anchor on a bridle is the most positive solution, but maybe not viable in crowded anchorages.

Palarran · 28-06-2019, 05:51

Personally I don't think there is a solution besides a second anchor and as 44 said, it doesn't work with other boats around. I hate when all the mono's are facing one direction and I'm 180 degrees opposite. This is why I went with a ton of chain so I can anchor in deep water.

thinwater · 28-06-2019, 06:09

The problem, of course, is that what ever you do, the wind and tide will soon change. Normally this is a light wind problem, and 95% of the time if you simply ignore it, it will sort itself out. If it does not, release one side of the bridle, let the boat spin out, and then reattach. Chain helps.