Is this a "drag proof" anchoring strategy?

[Auklet]

I have not done it often, nor I have seen it often done, but deploying two anchors off the bow set at, say, 45 deg angle from the bow does not seem a good idea. Doing it is more trouble (time) deploying and recovering. If the boat swings through 180 deg during the night and crosses the rodes, then you have a tangle that’s hard to undo. It’s doubtful you’re accomplishing much with respect to holding power, as the boat is basically laying to only one anchor at a time. However, if you’re really depending on two anchors for holding power, if one starts dragging then the other should too. So, they drag into each other and now you have a mess to solve before the attempt at reset.

As I see it, deploy two anchors only to make a Bahamian moor, a Hammerlock moor, or to accomplish bow-stern mooring. If you are really concerned about holding carry two anchors, a working anchor and a bigger storm anchor. Choose one or the other to use for the conditions. The CQR is a type of plow anchor with relatively narrow palms. Actually looks a bit like a plow. Other “plow types” have wider palms. The Suncor Plowmaster is on a swivel like the CQR but with much wider palms. It digs in, sets well, and holds well, at least up to 30 kt by my experience. The Rochna and Mantus are very wide plows (wide palms) without the swivel. So have a different way of digging in and setting. Their wide and relatively flat palms make them good holders once dug in, as many have attested to. But they are ungainly in appearance and hard to stow aboard if taken from the bow roller unless can be disassembled (Mantus). The SS 45# Plowmaster has been excellent for my needs.

[singlespeed]

Far too complex for a hurried retrieval. Think how much fun it will be to pull in this rig if you have another boat dragging down on you or both anchors drag.

[RaymondR]

There are limitations to the size of the anchor one is able to rack on the bow of a vessel or be stowed below.

In my previous boat, which was built so that whole sections of the cabin sole could be lifted out, I carried a monster modified Danforth style anchor as a cyclone anchor in a rack in the bilge. The replacement vessel does not have this storage capability although I retain the anchor in storage at my summer cyclone avoidance base.

During my winter cruise of 7-8 months and generally 2,000 or so nautical miles I very seldom overnight so go to or remain at anchor for about 200-250 nights of the year in say 50-60 different anchorages. Of these there are two where I always deploy two anchors. In one of them, because of strong tidal streams, I deploy the anchors at 180 degree phasing, in the other about 45 degree phasing because of "bullets" and the fact that as a well used anchorage the bottom is well plowed mud over a firm clay. One of the things which surprises me about this anchorage is that it is the larger primary with chain rode which slips until the secondary shares the load. The third circumstance I occasionally encounter is an anchorage where a shoreline shelf rapidly drops into deep water, there are two of these I regularly visit.

To avoid the speculated "tangle" problem I attend to the ground tackle about twice a day and use a couple of techniques to fairly readily remove the twists without a great deal of effort. Since I can use the capstan on the anchor winch to retrieve the secondary rope rode and have twin rollers at the bow and can store both anchors on the bow anchor rack retrieval does not generally pose a problem.

Since I have not dragged anchor for at least 12-14 years I can comfortably state "It works for me."

[carstenb]

Anchoring is a subject that really is more a religion than scientific fact If it works for you - great keep doing it

When we first set out for blue water cruising, we had many discussions with Peter Smith (Rocna inventor) and Greg Knudsen (Mantus inventor) about anchors, anchor sizing etc.
Both were adamant - if our primary anchor was also going to be our storm, hurricane etc anchor - buy an anchor 1 size up from what is recommended on their websites.

We have a Mantus and after something like 1500/2000 nights at anchor is various locations, substrata, conditions over a large part of the world, we have dragged exactly once (our own fault, but in our defense it was at Fatu Hiva where everyone drags)

We do carry a large fortress as an emergency anchor and a small fortress for stern anchoring.

This really isn't rocket science - while tandem anchoring has its place - ti is not an option to be used indiscriminately or in other than extreme need/conditions

my 2 cents - worth what you paid for it

[Auklet]

Seems to me a lot of “science” has been applied to the subject of anchoring. Specifically with respect to static load tests as a function of anchor size, anchor type, substrate, and scope. The “religion” part, I think, comes with testimonials, commercial or private. One can either listen to someone else, i.e., take advice; or, “look it up”, or work it out on your own. “Trial and error” is how science proceeds, generally.

[thinwater]

Originally Posted by singlespeed

Far too complex for a hurried retrieval. Think how much fun it will be to pull in this rig if you have another boat dragging down on you or both anchors drag.

Yes. In that case, one anchor.



You are assuming that everyone anchors in places where this is commonly a concern. For many of us this is nearly never a concern.

[newhaul]

Originally Posted by SailingHarmonie

Or you can ditch the CQR annchors and get a modern anchor that’s big enough for the boat. Your choice.

We don’t drag, so have no use for complexity like this.

Either you are not telling the truth or you have done little anchoring in varied substrates.

Every anchor will drag under the right conditions. Now Steve( SV panope has done a lot of testing and has shown that fact. There were even some situations where the cqr was actually the best holding . Now the Bruce copy is always the worst .
https://youtu.be/jQyD-8MB9VA

[newhaul]

Originally Posted by boatman61

If it's more than 10yrs old design it's an antique..

What antique anchor do you use?

[jvolpehoo]

Thinwater,**

thank you for validating (I think) my method for setting 2 anchors off the bow of my catamaran . As you suggest, My situation fits your description.
* I can handle my 2 main anchors by hand and neither one has independently failed me once power set.
* A 31 ft sailing cat may not need an electric windlass but I have a lewmar 700 windlass
* I do not want anchors I can't lift nor heavy chain and prefer the "give" of nylon.
* I have a single self launching bow roller.

My standard practice is to power set my main 23 pound CQR to my port bow with 15' of 1/4 chain spliced to 1/2" 3 strand nylon rope . I then bridle that to my starboard bow with a 15' dock line with a rolling hitch. If winds are expected to be over 30 knots I add my 10 pound fortress (identical chain/nylon rode) within 5' of the CQR drop. Once the CQR has been power set I manually set the fortress which brings it back more in line with the point of swing. I then rolling-hitch that rode to the starboard dock line just behind the bridle point. This adds redundancy should one of the anchor lines part. I then power set again from the bridle Position. The boat swings Normally and the anchors reset after tide and wind changes. The anchor lines apparently do ride over each other so haven't tangled. My thinking is that if one anchor pulls the other will hold through the "rubber band" motion of the nylon. And if both should pull I have a greater chance* of getting a reset. I have not tested this in much higher than 40kt gusts. I also set anchor alarms.
However, the overwhelming opinion in this thread is that a single oversized modern anchor design is certainly simpler and more effective.* So, for a 31 ft Prout Catamaran, what size Rocna? My windlass accepts only 1/2" rope.

[thinwater]

Originally Posted by jvolpehoo

Thinwater,**

thank you for validating (I think) my method for setting 2 anchors off the bow of my catamaran . As you suggest, My situation fits your description.
* I can handle my 2 main anchors by hand and neither one has independently failed me once power set.
* A 31 ft sailing cat may not need an electric windlass but I have a lewmar 700 windlass
* I do not want anchors I can't lift nor heavy chain and prefer the "give" of nylon.
* I have a single self launching bow roller.

My standard practice is to power set my main 23 pound CQR to my port bow with 15' of 1/4 chain spliced to 1/2" 3 strand nylon rope . I then bridle that to my starboard bow with a 15' dock line with a rolling hitch. If winds are expected to be over 30 knots I add my 10 pound fortress (identical chain/nylon rode) within 5' of the CQR drop. Once the CQR has been power set I manually set the fortress which brings it back more in line with the point of swing. I then rolling-hitch that rode to the starboard dock line just behind the bridle point. This adds redundancy should one of the anchor lines part. I then power set again from the bridle Position. The boat swings Normally and the anchors reset after tide and wind changes. The anchor lines apparently do ride over each other so haven't tangled. My thinking is that if one anchor pulls the other will hold through the "rubber band" motion of the nylon. And if both should pull I have a greater chance* of getting a reset. I have not tested this in much higher than 40kt gusts. I also set anchor alarms.
However, the overwhelming opinion in this thread is that a single oversized modern anchor design is certainly simpler and more effective.* So, for a 31 ft Prout Catamaran, what size Rocna? My windlass accepts only 1/2" rope.

Based on my PDQ 32 (similar, slightly more windage maybe) you will want a 35-pound new generation anchor, if you want to use just one 98% of the time (I had a Manson Supreme). Personally, I'd opt for Viking, Excel, or Mantus.


I like 100' of chain. That is a reasonable amount of weight and will have you on all-chain 95% of the time. Then use a separate nylon bridle that you replace every year or two. Attach the bridle to the chain with a bridle plate or chain hook of some type (or a Dyneem prusik or a soft shackle), and attach the rope to the rope rode (when that much is out) with a prusik hitch. The prusik is stronger, grips better, and is more reliable than the rolling hitch.


Cheers!