Adding a second anchor to the main anchor.

[BobnLesley]

Maybe so, I think you should maybe advise the RYA that their suggestions of application of an"angel" on the anchor will possibly give it a better holding.

Based on my own experience, I soon began to feel that deploying an angel/chum in strong winds just wasn't worth the risk to anchor recovery that it added; it never appeared to make much difference to the chain line/catenary anyway. The only time we consistently used one - a 10kg barbell weight on an old sliding genoa car - was for the stern-anchor rode when mooring bows-to in the Med; it provided a bit of 'damping' against passing boat washes and more importantly, got the rope descending at a steeper angle so keeping it clear of close-passing propellers.

 

[t21]

I'm with the One Massive Anchor brigade. Having two risks twisting them and all sorts of extra nightmares which is fine in nicely boaty weather, not when you actually need the thing to Hang On. I seem to remember Mirabella5 had two anchors nicely fitted at the bows, but still didn't hold in big wind... some time earlier the lovely looking anchors were shown on the back of a Toyota pickup and I remember thinking - I'd prefer if just one anchor about the size of the pickup truck please.... Monster, monster anchor. Bigger than that. And not stainless chain or any not-very-strong stainless stuff involved. Swivels - forget that too.

 

[Sybarite]

Just a couple of random thoughts: if you are anchoring in tandem then the distance between the two anchors should be greater than the depth so that you are not lifting both at the same time; the problem with anchoring in a V formation (according to the Rocna people) is that only one is holding effectively and if that drags, the weight shifts to the other and so forth.

 

[pyrojames]

I've used a V at about 45-60 degrees one CQR and the other a danforth. It wasn't so much the two anchors working together, but the reduced snatch from the boat not moving forward in a lull, and then paying off one way or another and coming up with a snatch. Snatching seemed much reduced. The distance between anchors only need to be less than the scope you have run. We would drop one, veer off to drop the other while paying out, drop the second and then veer out the other. Adjust each rode to suit once you had dug in and settled.

 

[noelex]

We would drop one, veer off to drop the other while paying out, drop the second and then veer out the other. Adjust each rode to suit once you had dug in and settled.

Deploying a second anchor substantially increases the weight of the ground tackle deployed. Even ignoring the extra hassle, risk of tangles and the creation of different swing circle to other boats in the anchorage, the technique needs to make a to make a very significant difference to security before it is judged as successful.

Adding even a small percentage of the weight of the second anchor and rode to the primary anchor is likely to be more effective and far less trouble in my view.

 

[geem]

I've used a V at about 45-60 degrees one CQR and the other a danforth. It wasn't so much the two anchors working together, but the reduced snatch from the boat not moving forward in a lull, and then paying off one way or another and coming up with a snatch. Snatching seemed much reduced. The distance between anchors only need to be less than the scope you have run. We would drop one, veer off to drop the other while paying out, drop the second and then veer out the other. Adjust each rode to suit once you had dug in and settled.

We have used a second anchor on nylon rode, no chain, in a vee when we knew the blow was coming from a certain direction. I was told the technique by a friend who had laid out multiple anchors in the Bahamas where he lived at the time, to deal with hurricanes. The theory being that with two anchors, one on chain the other on rope, you always have load on both simply because the stretch on 300ft of rope is huge.
I mentioned this practise to a tug boat captain in Curacao. He was Dutch and very used to the practise. He said they would anchor oil rigs when they were moving them and a storm came. They use chain as the main anchors and steel cable for additional anchors as it stretches and therefore shares the load better.

 

[Star-Lord]

I have not used tandem anchoring a great deal, but most that have tried the technique more extensively don't seem particularly impressed.

This was one example I managed to photograph. The cruiser used a combination of a Rocna and a Brittany. Unfortunately, they used the wrong attachment point on the Rocna, but you can see the Rocna is acting just as a dead weight or Kellet. In gusts the Rocna was well above the seabed so obviously had no hope of setting: