England Ireland Find Havens
England Ireland Find Routes
Boat
Maintenance
Comfort
Operations
Safety
Other



Next Previous

Being a happy hooker - getting to grips with anchoring



Be the first
to comment

What is the issue?
Novices tend to forsake anchoring for the safety of a marina, harbour wall or the security of an established set of moorings. This is because they have not yet acquired the confidence to serenely sleep whilst swinging to an anchor. If those aboard have confidence in their ground tackle and the manner in which it has been deployed they will sleep soundly and untroubled. Whether or not their peaceful slumber is justified is irrelevant - only their perception matters.

Guests on a first cruise will often enjoy a full night's rest whilst the skipper lies awake contemplating the distressing consequences of dragging his anchor - he recognises the vagaries of anchoring, his gently snoring guests do not. If the anchorage is shared with other boats the consequences of dragging become even more far-reaching - other people will become ensnared in the debacle; there will be shouting and accusations and damage to other boats. And a shared anchorage provides the opportunity for the uncertain anchorist to worry about other boats dragging, because if you don't trust your own anchoring arrangements, how can you trust anyone else's?

Why address this?
Getting to grips with anchoring is central to cruising. It dramatically reduces the berthing costs and brings you closer to the space and beauty of the natural environment. This is largely a function of confidence and in this article, the long-established practical seafarer Salty John, who specialises today in a select collection of tried and tested sailing equipment Experience, shares his experience to provide the practical information that you need to build up that confidence.

How to address this?
Fear not. With experience comes confidence and with confidence comes peace of mind and gentle sleep. Each successful anchoring experience reinforces the belief that the boat can be securely attached to the seabed - all it takes is the right tackle and the right techniques:

GROUND TACKLE

The first requirement is to have at least two anchors of proven design and adequate weight for the boat and conditions. In Salinas, Puerto Rico, we watched a boat drop a pair of intriguing scimitar-shaped hooks which may well have gripped the bottom like limpets but they had me feeling very nervous and glad to see their owner on his way next morning.

CQR Anchor
Photo: CC0
My choice has been the genuine CQR, although I'd sleep soundly to a Bruce and, in mud, a big Danforth. I’ve heard good things about the Delta but have never tried one.

There are many other anchor types which may or may not perform well, but only personal experience can develop the confidence that allows you to leave your boat in their hands.

A comprehensive anchor comparison test was conducted by Practical Boat Owner magazine in conjunction with BoatUS in 2011 and it showed the benefits of more modern anchors. The tests were conducted over a sand bottom using the following anchors and a brief summary of the results listed (best first) on their efficiency rating is the figure given):

  • • 6kg Spade - Efficiency Rating of 24

  • • 15kg Spade - Efficiency Rating of 32

  • • 4 kg Rocna - Efficiency Rating of 21

  • • 16kg Rocna - Efficiency Rating of 30

  • • 7 kg Manson - Supreme - Efficiency Rating of 12

  • • 11 kg Manson Supreme - Efficiency Rating of 21

  • • 7kg Delta - Efficiency Rating of 8

  • • 16 kg Delta - Efficiency Rating of 11

  • • 7 kg CQR - Efficiency Rating of 7

  • • 21 kg CQR - Efficiency Rating of 8

  • • 6 kg Bruce - Efficiency Rating of 5

  • • 16 kg Bruce - Efficiency Rating of 6


These tests were all conducted in medium/hard sand so what may be experienced on other seabeds can vary but the 'order of performance' would most likely be significantly the same. The CQRs problem in this test was attributed in part to the hinge which caused/allowed the anchor to snake around.

A Rocna anchor with its distinctive 'roll bar'
Photo: Courtesy of Rocna
Another devotee of the trusty CQR, that saved him in a 1988 storm in the Inner Hebrides, is Professor John Knox who came up with similar results when he tested many common anchor types in August 2011.

Knox performed his tests in two types of seabed found off his native Scotland: course wet sand and wet sandy mud but he pointed out that in very different seabeds, results would have been different.

Using the 6kg Spade as the 'benchmark' after 9 tests, about which others are defined, gained a score of 120kgf. He concluded that the Ultimate Holding Force UHC = the maximum Capacity the anchor will hold without moving in the seabed. The ability to initially penetrate the seabed and then the ability of anchors to stay held fast to the seabed rather than dragging or breaking out, gave the most significant variables between anchors. The anchors he tested are as follows, listed with the best performers at the top:

  • • Rocna 15kg = 480kgf

  • • Spade 15kg = 420kgf

  • • Manson Supreme 25kg = 225kgf

  • • Delta 35lb = 186kgf

  • • CQR 45lb = 175kgf

  • • Spade 6kg = 120kgf

  • • Rocna 5kg = 85kgf

  • • Bruce 15kg = 80kgf

  • • Delta 15lb = 76kgf

  • • CQR 15lb(dug in by hand) = 68kgf

  • • Bruce(Marathon)15kg = 50kgf

  • • CQR15lb = 44kgf

  • • Bruce(Atlantic) = 43kgf

  • • Bruce 5kg = 35kgf

  • • Delta 9lb = 34kgf

The efficiency= UHC/Weight, put the Spade just first, Rocna a close second, with the Manson third. The rest were very much behind the leaders Delta, CQR and Bruce in that order.

Many newer designs have been continually shown to work better than the old familiar anchors. In particular, the "roll bar" anchors like the Rocna, Manson Supreme, and Wasi.
Please note

eOceanic's founder's observation (Michael Harpur). I had exactly the same experience as John and swore by my a genuine CQR that I had on Obsession whilst sailing around the world. Today I would be genuinely hard pressed to recall it ever letting me down in three years. But not all CQRs are made equal, there are many variants from the original and some do not function as well. The one that shipped with my Bavaria 46 I found to be pitiful in and around The Solent. I replaced it with an oversized Rocna and found it to be completely reliable. It only failed me once in the soft muds of the Beaulieu River but that was my fault as I had not taken the time to dig it in properly being so overly confident in its setting and holding capability. The good news for the newcomers here is if we old sea salts swear by technology that has been vastly outclassed by modern anchors, you have the decks very much stacked in your favour from the get go.



For those intending on upgrading their anchors, or checking the rating of their current one, there are a wide variety of tests available on the web. The below links are to various sailing magazine articles relating to anchors and anchor testing that are available to download in PDF format:


ANCHOR RODE
(Often called the anchor cable)

I recommend that at least the primary anchor be deployed on an all-chain rode with a manual or electric windlass Experience to handle it. When I advocate an all-chain rode I am referring to the normally deployed section of rode. It makes no sense to keep 300 feet (90 metres) of a heavy and expensive chain in your bow locker if no more than half of it ever sees the light of day. In fact, it can be a hazard - a friend who normally anchors in depths of 20 - 30 feet found himself seeking shelter from a bad blow in a deep bay. When he came to drop the hitherto unused and undisturbed section of his chain he found it had congealed into a ball of rust and he had to crawl into the locker with a hammer to bash it free. 150 feet (45 metres) of chain will provide adequate scope in anchorage's up to thirty feet deep (10 metres).

The accepted ratios of rode length as a multiple to depth (X:1) from the bow attachment are as follows to enable a sufficient lower angle of pull to increase anchor holding power:

  • • 5:1 is minimum when overnight anchoring or leaving boat

  • • 3:1 is minimum in mild conditions (e.g. "lunch hook")

  • • 7:1 or greater for storm conditions

  • • 10:1 is considered max scope (anything more is excessive)

As wind/currents increase, catenary, the sag in the rode caused by weight along the chain, is reduced. In storm conditions, a chain rode can become bow tight. Additional lengths of chain can be carried in the bilge, or another low-down amidships location, for contingency use.


Windlass and chain with a chain hook attached
Photo: CC0


Many boats use as their primary system a rope/chain combination in which the chain leader is only a boat length or so, long. This introduces the spectre of a parting rope-to-chain splice and chafe Experience or laceration on rocks, coral, or bow-roller. A windlass is still necessary to handle the chain leader but there is the complication of switching from chain to rope gypsy during recovery. An all-chain rode never leaves the windlass, giving great control. Also, chain self-stows, avoiding a snake’s honeymoon of soggy nylon on the fore-deck which must then be coaxed down the naval pipe. And a final point in favour of a chain is the reduced scope required and the attendant smaller swinging circle. With Adriana's all-chain primary rode we use a scope of 5:1 or 80 feet (25 metres), whichever is longer. With rope we'd need 8:1 to keep the pull horizontal and the shank down; that's 150 feet (45 metres) in a typical Caribbean anchorage. When the wind dies at night, boats anchored in this way tend to go walkabout, drifting aimlessly and, perhaps, nudging a neighbour. When the wind pipes up, they career around like demented bungee-jumpers.

What, then, are the perceived advantages of rope/chain combinations? Well, nylon rope is substantially lighter than chain and this keeps weight out of the bow, and makes manual anchor recovery less back-breaking. With chain, it is important to arrange stowage as low and as far aft as possible, perhaps leading the chain there via a plastic drain pipe. Selecting the right chain for the job is important; high test chain, G4, is lighter and more flexible than proof coil for a given breaking strength. And, as I have already said, only stow enough chain in the locker to handle normal anchorage depths.

Ease of manual recovery is a moot point because I consider that a boat without a windlass is not properly equipped for cruising. If you have a windless you can handle chain; if you don't you will find manhandling your anchor becomes a chore on an extended cruise and you will, sooner or later, be checking your favourite marine catalogue for a good deal on a windlass, or the yellow pages for a chiropractor.

Nylon rope is cheaper than chain. This is an important and undeniable advantage of nylon over chain. The second anchor on Adriana is carried on 30 feet of chain and 300 feet of nylon. This is a compromise born of the need to minimise weight in the anchor locker and maximise weight in my wallet.

Nylon rode is quieter than chain; it doesn't crash on the bow-roller in surging conditions. To gain this advantage for chain a chain-hook and snubber Experience is used. The nylon snubber is connected to the anchor chain via a chain-hook, that slips over a link of chain, or directly via a rolling hitch Experience. Let out some more chain until the snubber then takes the anchor load to a cleat or Sampson Post, absorbing the shocks and leaving the chain hanging in a loose bight. Should the snubber chafe through, the chain retakes the load. Eventually, we dispensed with the clunky chain hook in favour of attaching the snubber line directly to the chain with a rolling hitch. We found this more positive than the chain hook and more deck and toe-friendly.



A snubber is also useful in anchorages where the swell comes from a different direction to the wind, curving around a headland, perhaps. The boat, lying to the wind, may take the swell on the beam and roll uncomfortably. In this case, lead the snubber line all the way aft to a cleat or sheet-winch on the side away from the swell. Then, as you let out more anchor chain, the boat will turn her head toward the swell as the anchor lead point moves aft. This bridle arrangement can mean a good night's sleep in an otherwise impossibly rolly anchorage.


WINDLASS AND ACCESSORIES

The windlass can be manual or electric; if it’s the latter be sure the engine is running when hoisting anchor as the current draw is substantial. Adriana has a beautiful bronze electric windlass made by Ideal Windlass in the U.S.A. It is technically a capstan, having the rope and chain gypsies rotating on a vertical drive shaft, and it provides a pull of about 500lbs at the press of the foot switch. Manual operation is available should I wish to conserve power or punish the crew. The unit can be serviced in ten minutes armed with a screwdriver and a pot of winch grease. Unfortunately, it is a particularly heavy device so that, combined with the weight of the chain it is there to control, Adriana is inclined to hobby-horse her way forward. On smaller boats, I would consider a lighter manual unit.

Be sure that the windlass is located in such a way that the chain feeds directly into the locker as it is stripped off the gypsy, and that there is sufficient available depth in the locker to accommodate the incoming chain without requiring manual flaking. With an all-chain rode secure the bitter end with a nylon line long enough to allow the chain end to be brought onto deck so you can untie or cut it without having to crawl into the locker.

A naval-pipe with a cover, a locking pawl for the chain, and a sturdy bow-roller complete the hardware list. Having the right gear is half the battle for tranquillity at anchor. The other half is knowing how to use it. In situations where poor holding is experienced a 'sentinel Experience', also known as 'kellet', might help make the difference.


ANCHORING TECHNIQUES

Anchor defensively and considerately. Keep away from immovable objects such as rocks, reefs and docks into which you could swing as the current reverses or the wind shifts, and keep well clear of other boats, no matter how attractive the crew taking nude deck showers might seem.

In the Virgin Islands it always amazed us that, no matter how close we anchored to shore, someone would always try to squeeze between Adriana and the beach. Even when we were the only boat in the bay we would have people come in and anchor with their stern just a short step from our pulpit. These sailors had not learned to anticipate where their boat would end up once they had fallen back and stretched out their rode.

Anchoring is actually quite simple; many people who are neither brain surgeons nor rocket-scientists become quite good at it. We lay at anchor for 300 days of a year-long Caribbean cruise, never in one spot for more than five days, and we dragged only once. That was when we put the CQR down in the grass and a squall blew in. Fortunately, we didn't hit anything, but one should be aware that the consequences of a dragging anchor are almost always bad.

If you have been secure and you start to drag it is because something has changed and probably not for the better. An increase in wind strength, a wind shift or a change in current direction are the most common culprits. You would be most fortunate to simply drift out of the anchorage into open water without hitting a boat on the way, although we once watched a 50' charter boat thread it's way out of crowded Leinster Bay, in the USVI, as if some ghostly hand were at the wheel and she was well on her way to Jost Van Dyke before the sleeping crew realised what was happening.


ANCHORING PROCEEDURE

Decide where you want the boat to be. To achieve this, estimate where the anchor must be, and allow for substantial error in judgement. Bring the boat to a stop facing up-tide or upwind, as appropriate, at the spot where you want the anchor to be. Lower the anchor and pay out rode as you drift or motor downwind from this spot.

At this time do not put strain on the rode or you will simply drag the anchor downwind of the target spot, and you will eventually end up with your stern a short step from my pulpit. When you have laid out the required scope, lock the windlass clutch and snub the anchor. It should now grip and stop your downwind progress. Apply some engine power, about half revs should do, to set the anchor and stretch out the rode. The anchor will continue to bury over time as the current action and the boat's motion worry away at it. Applying full power at this stage will just drag your anchor along the bottom unless you have a particularly puny power plant.

Once the boat has settled you will want to check that you are holding by reference to transits on fixed objects ashore - this is probably best done before settling down to those sundowners.


ONE ANCHOR OR TWO?

In most conditions, a single anchor of adequate size, deployed on a length of chain five to six times the distance from bow roller to the seabed, will be perfectly secure. Almost all anchors will roll over and reset themselves as the tide turns or the wind shifts. In some conditions, however, you may feel more confident having two anchors down. There are three configurations available when using two anchors, each designed for specific circumstances:




One from the bow, one from the stern: A stern anchor is used to limit the boats swing in a very confined anchorage. The advantage of holding the boat almost stationary where there is the danger of swinging onto rocks or into shallow water is obvious, but if other boats are sharing the cove it is wise to check that they are using the same technique or that their swinging circles take them well clear of you.




The Bahamian Moor: The second anchor is led from the bow, but in the opposite direction to the primary anchor. This technique is used where there are strong reversing currents, as in many of the Bahamian anchorages including Nassau Harbour. The boat lies first to one anchor and then, as the current reverses, to the other. This avoids having the boat swing in a huge arc from one side of a single anchor to the other, whilst enjoying the inherent safety of having two anchors down. In short more effort, but much less angst!

When setting the 'Bahamian Moor' I always set the second anchor from the dinghy, piling anchor and sufficient rode onto the stern seat and paying it out as I row away from the boat. It is possible to avoid using the dinghy by falling back on the primary anchor the appropriate distance, dropping the second hook, and then motoring back to the mid-way point. This is less complicated if both anchors have identical rodes; if your primary anchor is on a chain and your second anchor is on a chain/rope combination you must drop back far enough to allow for the greater scope necessary with the rope rode.

The 'Bahamian Moor' is used in very specific circumstances, where strong reversing currents occur, and the boat is actually held by only one anchor at a time. The fact that another anchor is down is a comfort if the worst should happen, but do remember that for half the time you will be reliant on your second anchor which must be equal to the task.




Lying to two anchors simultaneously: Both anchors are deployed from the bow, about 45° apart, and, ideally, they share the load. This technique is used in strong winds, or where the consequences of dragging are particularly dire, or where the skipper directly downwind of you is standing on his fore-deck glaring. Having two anchors set, both on their proper scope, is a wonderfully secure feeling.

As above I usually lay the second anchor from the dinghy. Carol stands in Adriana's bow pointing me in the right direction because it is very difficult to judge the correct angle from sea level. However, it is possible to set the second anchor the lazy way, simply motor to the spot where the second anchor should lie, dragging the primary rode with you, drop the hook and fall back onto both rodes. If you can live with yourself after damaging the seabed like that, go ahead, it's a very effective method and in common use.

Although lying to two anchors is a very secure feeling there are occasions when, perversely, you would rather not have this complication, in case you have to cut and run: A nasty night in an exposed Bahamas anchorage with the prospect of a significant wind shift had me torn between the security of two anchors and the mobility of having just our primary hook on the trusty windlass. What I did was to drop the second anchor onto the seabed under the bow but kept the rode coiled on deck ready to run out and give us a second chance if the primary dragged. Minimum fuss would have been necessary to recover the gear and clear out had the wind gone round, putting us on a dangerous lee-shore.


ARE WE DRAGGING?

Until fully confident of their anchoring technique a crew will worry that the anchor may drag with no-one aboard being aware of it. Most GPS units have an anchor watch facility but I find that if they are set fine enough to be of real use they buzz at every wind shift. To avoid spurious activation the alarm should be set at 600 feet or more (circa 200 metres) and therefore its value is limited to large, uncluttered anchorages. Heath-Robinson arrangements of frying pans, string and plumb-bobs described in nautical how-to books will let you know when you have got your tidal range wrong or are about to hit the beach, but you'll probably be awake anyway worrying that the clatter of pots and pans won't wake you from a deep slumber.

A clever mechanical alarm system External link can be made up to resolve this. This device relies on the fact that a boat never drags towards its anchor, which in my experience is true. A plumb bob lowered to the seabed is connected to a magnetic switch that will only activate if the boat moves backwards from the plumb bob and not forwards or sideways. The switch activates a horn or flashing light.

Eventually, however, experience tells you that when a boat drags at anchor she turns beam-on, or almost so, to the wind, which generates such fundamentally different noises in the rigging and top hamper, and imparts such a distinctly different motion to the boat that you will be jolted awake just as assuredly as if a foghorn had gone off in your ear.

If you are in a crowded anchorage or to windward of danger and you anticipate deteriorating weather conditions you should arrange an anchor watch. Those that are off-watch will get a few hours of good sleep, which is better than having the whole crew sleeping with one eye open.


CONCLUSION

With the right tackle aboard and a good grasp of anchoring theory the process of building confidence can begin. Experience will test the theory, changes may be made to tackle or method but, eventually, the sailor will develop an anchoring system he trusts. The confidence trick has been mastered, the happy hooker is born!

With thanks to:
Salty John, specialising in a select collection of tried and tested sailing equipment. Web site: http://www.saltyjohn.co.uk/ phone +44 (0) 1995 672556 e-mail: info@saltyjohn.co.uk




Bahamian Moor




Anchor Scope




Heavy Weather Anchoring


A photograph is worth a thousand words. We are always looking for bright sunny photographs that illustrate this experience. If you have some images that we could use please upload them here. All we need to know is how you would like to be credited for your work and a brief description of the image if it is not readily apparent. If you would like us to add a hyperlink from the image that goes back to your site please include the desired link and we will be delighted to that for you.



Add your review or comment:

Please log in to leave a review of this tip.

eOceanic makes no guarantee of the validity of this information, you must read our legal page. However, we ask you to help us increase accuracy. If you spot an inaccuracy or an omission on this page please contact us and we will be delighted to rectify it. Don't forget to help us by sharing your own experience.