I set a second anchor most times and especially during expectant foul weather and it has saved my butt on more than one occassion and I sleep better.In the BVI this New Yrs.,the weather was a concern and my GPS was out which meant the alarm was out also so the second anchor was imperative. I generally set it a 45 degree angle either side depending on surrounding boats or topography. Strangely, I can't seem to find a good article referance and /or diagrams etc. offering any further tips. Anyone have any ?? Paul

I had come across this article at SailNet a couple of weeks ago. I found it very helpful and has given me the notion to use this technique more often.
http://www.sailnet.com/collections/articles/index.cfm?articleid=woodto052

Martin

We at Rocna anchors would comment that with a decent anchor you should not need to be using a dual set-up in anything but extreme conditions.

In those extreme conditions, we recommend a tandem anchor as opposed to a second anchor. This is where you attach the second anchor in-front of the first; i.e. you have one anchor, rode from it to the front of another, then rode from the second to the boat.

This system has several advantages:

- The boat can swing more easily
- Load is distributed equally between both anchors at all times (with a dual 45 degree setup, 99% of the time, one anchor or the other is bearing all the load)
- It is easier to launch and retrieve

All Rocna anchors come with a dedicated attachment point for a tandem anchor, located in the correct place. Of course none of our customers have had occasion to use it yet

We talk more about tandem anchoring, and anchoring in general, in our User's Guide, which is available online. Go to www.rocna.com, and select "printable information".

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Craig Smith
Rocna Anchors
www.rocna.com

I have a different position regarding the use of two anchors..

If you use two anchors “V” set, you will not increase the holding of each of them, but as you can easily check the holding of each of them, you have more chances that they will both be set.. and if one drag, the other one would have some chance to hold..

On the same way, if one anchor rode will break. You will still be anchored on the second one..

Now, about the “tandem set “technique..

Or the “Double Trouble” technique:

Attaching two anchors to one rode, known as tandem anchoring, should be avoided.

The double approach attaches a second anchor with around 15’ of chain in front of the first anchor. I personally almost lost my boat trying out this idea. At the time, my first anchor dragged. Needless to say, it was an old generation model, so I decided to try something new. I added a smaller anchor in front of the large one. This worsened the holding power as opposed to doubling it, drifting swiftly on the smaller anchor while the larger one couldn’t grip at all.

On an imaginary level, it might seem like two anchors should hold better than one. This is however only true when both anchors can set perfectly. Whatever anchoring technique you use, there’s never a guarantee that both anchors are going to set well. On the contrary, once the first anchor is set in the seafloor, it will hinder the other anchor from setting also.

When an anchor has dragged, a trench formed behind it and this quickly backfilled with loose un-compacted sand. These areas can be still visible after several tides and may explain why some popular anchorages are criss-crossed with patches of poor holding.

Then, if the most proximal anchor set, they are very good chances (?) that the distal anchor will fall down in this loose bottom, with, as a consequence, a poor holding!.

I have done a series of approximately 70 tandem anchorages in the clear waters of the Med, diving on nearly all of them.. in 62% of the cases, only one anchor was set.. During bad weather, you will not have the possibility to dive to check your anchors.. and you only have to “trust” your anchors.. Which is what I call “the Russian Roulette” anchoring..

For those who insist on using two anchors on one rode, I offer the following suggestions:

• Only use two identical anchors, with the same size and model.
• The size of each anchor should be able to withstand the load of your boat on its own, without the second one.
• The two anchors should be separated by a piece of chain of around 3 to 5 meters in length.
• Never attach the chain from the second anchor directly to the first anchor; instead, attach it to the connector of the first anchor.
• Finally, remember that new generation anchors have holding power far superior to older models, and they do not suddenly disengage from the seafloor like plate or CQR anchors. Instead, they slowly drift, remaining embedded. I am convinced that a single new generation anchor with high holding power is safer and more reliable than linking two old generation anchors tandem set.