A dragging anchor on a lee shore is every sailor's nightmare. Michael Seamus Kildea explains how to anchor securely.
When it comes to anchoring there are about as many opinions as there are yachties. Everybody swears by a certain type of anchor or system of deploying it. By the time the new yachtie has broached the subject with half a dozen different people and received half a dozen different opinions, he is probably very confused.
Nothing can ruin your enjoyment of cruising more than worrying about dragging into rocks or other boats in the middle of the night or waking up to the jerk of the chain being pulled tight from a strong gust.
I have met yachties that sail to a tropical paradise, crossing 1,000 miles of open ocean with confidence, and then not enjoy the destination on arrival as they won’t leave their boat at anchor to go ashore for anything but the briefest intervals due to fear of their anchor dragging.
My wife and I live at anchor at least half our lives, we only pay for a marina or mooring when we stop to earn money. My main motivation for paying for a berth then is not so much that I am worried about Freelife dragging in my absence (although if a gale was forecast I would be reluctant to go to work) but I am concerned that another boat in the anchorage will drag its anchor and wrap around my yacht.
Over the last decade there seems to have been a general decline in anchoring skills. I’m not sure if it’s because of the increase in marinas and hire moorings, the increasing use of lightweight anchors, modern yacht design or something else. But these days if I am in a crowded anchorage and the wind gets up, a greater percentage of boats in the anchorage seem to drag.
We get hit by another boat dragging its anchor on average once per year by everything from yachts to trawlers. We now anchor defensively, i.e. if it’s going to blow we forgo the sheltered corner of the anchorage and move to the windward end so others drag away from us. We move if someone anchors up wind and I don’t like the look of how they have anchored. However, we still get hit occasionally. Conversely, if I see someone who I know is good at anchoring I will often anchor downwind of them, using them as a barrier.
Most of what I learned about anchoring I learned from other sailors who seemed to be doing it well with the odd bit of useful info gleaned from reading one of the many anchor tests that appear regularly in nautical publications. We had to learn as I am too cheap to pay for a berth most of the time. We learned to sail in the South Island of New Zealand, where you can get storm force winds whipping through an anchorage at night. Whilst you may get protection from the sea there is often none from the wind.
Anchoring is not rocket science, it can be easily learned. I think the problem for a lot of people is not knowing what to believe from the array of anchor tests, recommendations and claims. I won’t recommend any particular type of anchor. Personally I have a variety on board, some work better in different circumstances. I just want to share some general principles that should, when put into practice, give those who are having a lousy night’s sleep more confidence. You can get to a stage where you don’t have to wake up or maintain an anchor watch, unless things get really bad and by then you can’t sleep anyway. You can leave your boat at anchor while you go on a daytrip with confidence.
First of all any boat can drag, it doesn’t matter how good your skills are. Bear that in mind and don’t (as was the case with one yacht I rescued) leave your half million dollar yacht on an inadequate, poorly deployed anchor in Tonga, unattended while you fly back to New Zealand for three months. Also, don’t expect your anchor to hold for very long if you anchor on a lee shore amongst 2m breaking swells (another real incident that caused the loss of the vessel).
Anchoring is all about risk minimisation. There is some risk you have to accept in everything we do but you can get it down to a level where the risk is relatively small and conditions have to be quite bad before you start to lose sleep. Early in our yachting lives I went for the odd drag in an anchorage and that spurred me to study it in some detail and whilst the potential always exists it is now fairly infrequent. Despite living at least half our lives on the hook and anchoring everywhere from the roaring 40s to the tropics in the last ten years, we haven’t dragged. That doesn’t mean that I have the attitude that it will never happen, just that I have reduced the risk so that it hasn’t happened in 10 years.
Even if your arms aren’t as short or your pockets not as deep as my own, there are good reasons, other than saving money, to learn good anchoring techniques. For example, it widens the number of available anchorages, lowers the skipper’s stress level and it might save your boat if it’s going to blow and there are no marinas or hire moorings in the vicinity. I have never found a harbour that I can’t poke myself in somewhere and often while my friends are spending $25 per day on a hire mooring, I get to spend that on fish and chips and ice creams.
First of all select your anchorage with care, if there is no wind and a flat sea and it looks like continuing, you can probably anchor anywhere safely, so long as it’s not a high traffic area and you are likely to get run down. Have a good look at the chart for things like a foul bottom that might make getting the hook back up difficult. If you can avoid strong currents do so. Watch out for submarine cables. Look at the bottom type; mud and sand would be my preferences before heavy weed or gravel.
Protection from both sea and wind are ideal, but protection from the sea is more important. Wave action seems to upset your anchor more than wind.
Don’t overlook local knowledge and cruising guides (we use Alan Lucas’s books all the time), but always assess the source of the information as some sailors are more knowledgable than others. Many times we have had locals tell us “you can’t anchor there everyone drags there”, in an anchorage with an apparently good bottom in a protected situation.
You will need to make your own assessment of the information. Charts and cruising guides are normally accurate, but if they seem at odds with what you are being told at the local waterfront bar, have a look and see if anyone else is anchored there. A local live-aboard on the hook, who doesn’t own part of the marina, might be a good person to ask. Or just try it and see if the anchor seems to set. You might lose the odd anchor to a foul bottom but I haven’t lost a hook yet, touch wood.
Ok, so that covers where to anchor, now the how. When it comes to choosing an anchor type, by all means take advantage of written material on how different anchors perform in different situations, but if the test is conducted by someone who sells anchors I would take the info with a big pinch of salt. Invariably, after extensive and impressive sounding tests the anchor they sell just happens to be the best.
Also beware of recommendations by yachties who live mostly in a marina and perhaps cruise at a lattitude where they think heavy weather is 30 knots, recommending the latest lightweight, super-duper, space-age looking hook. If I am going to accept anecdotal evidence of an anchor’s performance I will give it more weight if the person offering the advice has spent a long period of time living at anchor in a variety of locations and conditions.
The following are general principles that I have gathered from a variety of sources over the years that I have found to work well for us. I have given this advice to friends with dragging problems who own a variety of yacht types and these general principles seem to have worked well for their yachts too.
First of all, size matters. When an anchor gets force applied to it that reaches the limit of that anchor's ability to hold in that particular sea bed, it first starts to plough slowly through the sea bed and if more force is applied it will drag; the point at which this happens changes according to weight and surface area. All other factors being the same, the heavier, larger anchor of the same type, will stand more force before it drags. As a general rule of thumb I try and go at least two sizes bigger than the anchor manufacturer recommends for my type and displacement of yacht.
Obviously we can’t all have 200kg ship anchors hanging off the bow roller, but when setting up your windlass, chain and rode package keep the principle that ‘size matters’ in mind. Regardless of the type of anchor, get the biggest version of it that you can stow, deploy and recover. The obvious exception to this is the kedge anchor which must be small enough to handle from a dinghy if you run aground.
Second is type, the following are the ones I have experience with. No doubt there are numerous other good anchors around. Most anchors hold well in sand and mud, which fortunately is the most common bottom type, but don’t put all your eggs in one basket. When it comes to rock, the good old fisherman anchor sometimes called the ‘yachtsman anchor’ is great. We spent two months lying to it in Port Vila, Vanuatu, through some very snotty weather. Port Vila has notoriously poor holding with most opting to hire moorings when the wind gets up as the bottom has a thin layer of sand over rock. I dropped the fisherman down and jumped in with my snorkel, found a nearby hole in a rock that I dropped a fluke of the fisherman into and we weren’t going anywhere. I did have to dive back in to take it out by hand when we wanted to leave though.
The fisherman doesn’t have the surface area to be much good in normal sand and mud, but in rock it’s great, and it comes apart and is relatively easy to stow (it can also be useful in a heavily weeded bottom).
Then there are ploughs (CQR/Manson type), claws (Bruce type) and all the modern derivatives and copies of them, which are great for sand and mud and will sometimes hold in other bottoms. The plough types seem to set better on some bottoms and the claw types on others.
Then there is the Danforth type with their large flukes giving good holding in relation to their size. These have a peculiarity in that they may not reset as well as the claws and ploughs if the direction of pull is reversed, i.e. if the wind or current reverses direction. Most of the time they will cope ok but they are a bit more prone to pulling out if the direction of pull is reversed. Sometimes the chain can foul the anchor and drag it sideways across the bottom, not allowing it to reset.
In the right place the Danforth can be wonderful, if moored Mediterranean style, stern to a wall, the direction of pull doesn’t change, or in a river anchored bow and stern so that you don’t swing. We have two on board, a smaller one which we use as a kedging anchor. It sits on the pushpit ready to throw in the dinghy and row out if we touch bottom on a falling tide. We just drop it in the direction of deeper water, hook it to the spinnaker halyard and use a mast winch to pull the top of the mast towards the anchor. As the yacht heels the draft is reduced and the yacht slides towards the anchor and into deeper water.
Another option is a Flook. This anchor has a large surface area and is designed to ‘fly out’ from the boat. The Flook also has an elbowed shank that is designed to dig deeper into sandy bottoms.
We also have a large Danforth which doesn’t see service often, but with its sharp points and large surface area it will often set in a hard-packed bottom when claws and ploughs just drag along the surface. A fisherman might penetrate but lacks the surface area to hold well, especially if the hard-packed bottom is a thin crust with softer ground underneath. You may not use it often but when you are tired, cold and just want to flop into bed and the others are refusing to set, you will be glad you have been carrying it around.
Just remember get the heaviest versions you can handle (if you can stow them on the bow rollers permanently, even better). We hedge our bets and have one of each permanently on the bow, which brings me to another point. Many first time cruisers will set off with one anchor of a particular type. As they gain more experience they learn that you need several anchors on-board, preferably of different types, so you can safely anchor in different conditions and in different bottoms.
Setting your anchor
Third and most important is how to set your anchor and the following should apply regardless of what type of anchor you have. First let's deal with scope. The old rule of thumb used to be three times the depth of water you are anchoring in at high tide. Research has shown that regardless of what type of anchor you are using or bottom type, that going from a three to one scope to a six to one scope doubles the holding power of the anchor before it started to drag. Interestingly, when the scope was increased to ten to one you only got a further ten percent increase in holding and beyond ten to one very little benefit from increased scope.
Now these scopes are assuming an all chain rode. If you have a mix of rope and chain you will have to increase the scope to achieve similar increases in holding power but the principles still apply.
The trick to anchoring with low risk of dragging is overkill. Don’t put down gear that should just cope with what is forecast, always set up to cope with more than what’s forecast. The Bureau of Meteorology regularly advises that actual wind strengths may be more than 40% above the forecast strength.
One or two?
Obviously it would not be practical to set yourself up for a storm if you are only stopping for lunch. Our rule of thumb for overnight anchoring is that if the forecast is for twenty knots of wind or less, we put down one anchor. If the forecast is for any more than 20 knots or if we are planning to stay at the anchorage more than a few days, we put down two anchors, almost always in tandem on a single rode.
When we have picked our spot and done a circuit of my predicted swinging area looking at the depths, I will head the boat into wind or current, whichever is the stronger. Look at other moored/anchored boats to get a good indication of what way you might lie. Then drop your first hook - don’t let the anchor hit the bottom and heap a big pile of chain on top as this might foul the anchor. You can generally feel when the anchor has hit the bottom (the chain normally runs out slower). Once the anchor is down, slowly veer rode up to the required scope as the boat drifts back, if no wind or current you might have to engage reverse to lay the rode out.
Once you have your six to one scope, secure the anchor rode. I normally put a short piece of braid, via a clove hitch, onto the chain and take the strain onto the Sampson post (or strong cleat), as most capstans were not designed for snubbing loads. Then you engage reverse, first at idle then gradually build revs. Line up something as a transit on the shore abeam of you and see if you are moving, also touch the rode with your hand or foot and you can feel what the anchor is doing. The vibration travels up the anchor rode when it is under tension and you will find you can feel if the anchor is dragging and even tell what it is dragging through, i.e. bumping over rock or sliding over mud.
If your partner is on the helm and you are on the foredeck, as is common with cruising couples, try not to shout things like “reverse” and “more revs”. You might only be trying to compete with the wind and engine noise and you end up sounding like Captain Bligh. You don’t want to suffer the same fate as him so work out some simple hand signals. We use: thumb down = engage reverse, point forwards = engage drive, one raised finger = idle revs, two fingers = medium revs, three fingers = high revs, closed fist = neutral, finger across throat = shut engine down.
If setting your anchor for heavy weather, rather than gradually increasing revs, you can give it a bit of a jerk to really check that it’s set, but only a modest jerk as the mass of your boat moving can greatly increase the pull.
If your anchor won’t hold, try again in a slightly different part of the anchorage with the same anchor, or try with a different anchor.
Don’t get frustrated when you’ve tried three times and it’s still dragging over the bottom. Generally that means it’s time to try another type of anchor. That’s why a variety on board is good. I haven’t found an anchorage yet where I can’t get one of my hooks to hold. Most of the time your hook will set first time, but just occasionally you have to do a bit more work to make yourself secure.
Time for the snubber
Then, if you are only putting the one anchor down it’s time to apply the snubber. The snubber is a piece of nylon rope that does a number of things. First is shock absorption - being stretchy, when a gust hits the yacht and she pulls up on the anchor rode, it softens the pull applied to the anchor, making it less of a jerk (also making it more comfortable inside). If you have a nylon rope rode it will provide the shock absorption anyway.
Second it provides some yaw control, in strong winds the yacht will try to sail about at anchor and head off first one way, then the anchor will pull the head around and she will head back the other way. This pattern will repeat itself. Some designs do it more than others. If severe, it’s not going to help the hook stay in the bottom (it can even cause me to spill my coffee). Now to be effective in controlling yaw the snubber must be a double one like a bridle, both arms must be the same length, it must come onto the boat well back from the bow. You may have to install fair leads to bring the snubber safely over the toe rail to avoid chafe. You might need to experiment bringing the snubber over the side at different points to see if you can reduce your yawing. I even heard of one sailor who took the heretic's view and attached the snubber to the stern corners of his yacht and it didn’t yaw at all.
The third benefit of the snubber is to let you apply additional weight to the rode to help dampen things, much like an anchor buddy (a weight slid down the anchor rode). If you already have your six-to-one scope out and still have plenty of chain left but you don’t want to increase your swinging radius, once the snubber is on continue to veer a big loop of chain, which will act a bit like an anchor buddy, i.e. when the rode pulls tight it has to lift this additional weight up before it can jerk on the anchor.
Fourth is that it quiets the clunking of the chain in the bow fitting. As the chain no longer has tension on it where it goes over the bow fitting it tends not to move about and make as much noise. I also put a small fender under the chain just aft of the bow roller and this pretty much shuts it up completely as the only bit with strain that touches the boat is the nylon snubber and that’s relatively quiet.
About that second anchor
If the forecast is above 20 knots of wind, or if you’re in a crowded anchorage, among moorings or near the shore and need to reduce your swinging circle or if you know you are going to be in the anchorage for an extended period, you should lay a second anchor.
I also use two when I am going to be away from the yacht for more than a couple of hours. I’ve only ever needed the second anchor once, but on that occasion it saved my yacht. My wife and I were anchored on Great Barrier Island off the north island of New Zealand. We were going for an all day bushwalk to some hot pools and even though I thought I was wasting my time I took the extra 10 minutes and set the second anchor in tandem. The forecast was for 10 knots variable and to continue.
We left at 8am. When we returned at 5pm it was pouring rain and a low had formed right on top of us and deepened quickly. The anchorage was protected from every direction except the S/W and you guessed it the wind was S/W. Our yacht was porpoising around in 2m breaking swells in a full gale about two yacht lengths off where the surf was breaking on the rocks. Getting out to the yacht in the dinghy was very scary with each wave threatening to flip us, and dumping water into the dinghy. Getting on board was even scarier, but thankfully the anchors hadn’t budged and we safely moved to a more sheltered anchorage.
I had set the Bruce anchor at a six-to-one scope, the plough on the same chain at a three-to-one, and had a snubber fitted. Maybe one anchor would have held but over the years the two-in-tandem set-up has had some good tests and has proven reliable. We have weathered blows that have put the rail under in gusts under bare poles and we haven’t moved. We’ve had a trawler and in another incident a 50 foot Spanish cruiser drag into us and lodge on the bow in a blow, but the anchors held. I could go on but you get the idea, two anchors gives you significantly better holding than one.
Don’t think that this two anchor set-up has made me cocky. If it’s going to blow hard I’ll stay near the yacht, but it has proved reliable enough that we now think of the tandem anchor set-up on a 6:1 scope with a double snubber almost like a portable mooring. In fact we have had friends on hire moorings who have had a mooring drag or break when our anchors held fine.
Setting the second anchor
To set the second anchor you should first set your primary anchor, then pull in the anchor line until you have about a 3:1 scope to the anchor on the bottom (this shouldn’t be enough to disturb the primary anchor). Then just shackle the second anchor to the primary chain, gently lower the second anchor making sure the chain doesn’t foul the anchor (you might have to engage reverse if there’s no wind) and keep lowering until it rests on the bottom, then drop back from that anchor a further 3:1 and put on the snubber. This will give you a 6:1 to the first anchor on the bottom and 3:1 to the second. You can’t pull on the second anchor to dig it in, but don’t worry. I have done this many times. If the wind remains light the second one you put down will just sit on top of the bottom and all you’ll get is the benefit of its weight, but if the wind gets up the movement of the boat will gradually set the second anchor and after all night lying to 25 knot winds, a quick dive on the second anchor will show that it has set.
The two together gives you double the weight of anchor on the bottom and significantly improved holding power.
Two anchor variations
There are a few variations of the two anchor set-up. If anchoring in rock, the second anchor I put down will be the fisherman. If in amongst swing moorings, I put the second anchor only at 2:1 from the yacht so I swing on a small circle like the moored boats, but if the wind gets up, we will all line up with the wind and I still have the first anchor at 6:1. Also for storm anchoring, if I have the room I put out all my chain and I am probably at more than 6:1 to the closest anchor and 10:1 to the first one I put down. While the 10:1 scope only gives marginally better holding, in this situation you want as much as you can get.
I have had yachties comment that they wouldn’t put all their trust in just the one anchor rode in case it breaks, but the same yachties are happy to pay for a hire mooring which is generally a single rode and an unknown quantity, whereas our rode is sized appropriately for our yacht and I check it regularly.
Getting two back on board
Recovery with anchors set in tandem on a single rode, even in adverse conditions, is relatively simple. Whereas if you set the second anchor on a separate line from a dinghy it can be hard to retrieve, particularly at night or in rivers where the current keeps reversing (in these situations the two rodes tend to tangle). With both on the same rode just winch in the first one and when it is at the bow roller take your time taking it off as the other one will still be holding in the bottom. Then when that is stowed, just pull up the second hook like normal.
When fitting the second anchor to the primary chain, usually with yacht short link chain, you can’t get a decent-sized shackle through the links so don’t try. Just get a shackle that fits over the link altogether, which is big enough to fit over the chain but not so wide it can move along the chain. If using a rope and chain set up you might want to attach the second anchor to the chain near where it joins the rope or if you need to reduce your swing and want to set it further up the anchor rope, use an alpine butterfly knot. This knot will take a pull from both sides and can be undone after force has been applied. Use a length of chain between the second anchor and the rode to allow the rode to lift off the bottom to reduce abrasion. In coral or rock tie a buoy to the line about the depth of the water back from the chain so its buoyancy can hold the rope off the bottom.
If you have a bowsprit and store both your main anchors on it like we do, get a short length of chain so that when you attach the second anchor to the main line you just shackle on the short chain to the second anchor, pass it under the bob stay and shackle the other end to the primary chain and then just lower the second anchor from the side it was already in. When you recover it and the short piece of chain is near the capstan, just secure the primary chain to a cleat with a clove hitch, then lift the chain off the chain wheel of the capstan, reach down and tie a clove hitch part way down the short piece of chain and lead it to the rope drum and let the capstan do the work rather than your back. You might need to hold the short chain once partially pulled in and retie the clove hitch further down until the second anchor comes up into its slot, but it means you don’t have to use your back.
As I said I won’t recommend any particular anchor. We have six on board if you count the dinghy one. Don’t be put off by storage problems, we had the same amount on my last yacht and it was only 29 feet long. If you are lucky you can leave the two main ones on the bow (lash them to the fitting when at sea). The kedge needs to be ready to go on the stern somewhere. For the others just use your imagination, if you look around you will find areas where you can epoxy in a shaped block with a couple of straps to secure it in a locker, under a berth. The ones you don’t use often don’t need to be as accessible.
If your vessel is a lightweight racer then weight may be a consideration but that doesn’t mean that you sacrifice seamanship for sailing performance. If you think about it, the extra anchors will probably only amount to the equivalent of having one extra person on board and at the end of the day they could save your boat. We are only 35 feet long, we weigh 13 and a half tonnes and we still manage to sail even if there is only light wind. Just ask the Brisbane ferry drivers who skilfully avoid us as we ghost up the Brisbane river with only 5 knots of intermittent breeze.
Anchoring, like sail trim, is a skill that needs to be learned and practiced. If you take the time to learn how to anchor correctly and invest in a good anchoring system, chain, rode, windlass, with a selection of anchors for various bottoms, you’ll find that you’re able to enjoy the solitude and beauty of anchorages without constantly worrying if you’re going to drag or not.
It is an unfortunate fact that many production boats, particularly racers, have light and inadequate anchoring systems. If this is your boat, then please recognise this shortcoming and have the decency to hire a mooring or stay in a marina so you don’t inflict damage on other boats.
Too many sailors are hesitant to set out two anchors because they haven’t tried it before and they’re worried about screwing it up and fouling their anchor. The solution to this is to practice your tandem anchor set-up in calm conditions. The next time you anchor try setting two anchors in tandem. After a few goes you’ll work out the kinks and feel comfortable using it in adverse conditions. The tandem two anchor set up we use hasn’t failed us yet.
Does following these steps mean that you’ll be able to sleep better? Yes. Does it mean that you no longer need to keep anchor watches? No, but you may find you’re able to anchor securely and sleep in conditions that would have seen you sitting in the cockpit previously. In adverse conditions you will still need to stand anchor watch, but that’s part of good seamanship.
Hopefully the information I’ve presented will be of assistance and enable you to minimise the risk of your anchor dragging and greatly reduce the stress on skipper and crew. You may even find that you feel more secure anchored than being on a mooring.