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This article is by Dave Mallett of Wavelength Training and first appeared in Sportsboat & RIB Magazine.

Anchoring - have you tried it?

Ask any potential powerboat instructor during his instructor course what he would do should his motor fail, leaving him drifting out to sea and he will invariably answer that he should anchor the boat. Ask him then to practically do it and it is more often than not obvious that they really have not got a clue and that most have never anchored a boat in their life.

 I suppose anchoring is not the “sexy boating” that instructors like to teach. It means cold hands and lots of wet rope laying about, and whilst it is on the RYA level 2 syllabus it is not on the examination circuit shown in the RYA powerboat logbook. So it is perhaps not surprising that many instructor candidates seem not to have been taught it during their original level 2 course!

What is also obvious is that many candidates have read about the subject in a book or two, and that those books have been yachting titles. When they start quoting figures for a sportsboat anchor warp and suggest three times the depth if using an all chain warp I have to ask just where they are going to put all this heavy chain in a fast planing boat and which superhero they are going to employ to lift it all from the seabed!

 Ok now that I have blown my top about that lets look at anchoring as such.

Anchors come in various shapes and sizes, and they are not just heavy lumps of metal as is a mudweight.  They have evolved over many centuries, or have been specifically designed to do the job. One thing they all have in common is the need for at a length of chain between them and the anchor rope.

Chain is there for two reasons. Firstly to prevent rope being worn away by the seabed or cut by sharp rocks. Secondly and more importantly in my mind, to make the anchor work at all! A length of heavy chain, and the heavier the better, keeps the pull to the anchor low down, along the seabed, and works as a shock absorber preventing the boat snatching at it as she rides the waves. Without chain the rope would be pulling upwards and would not cause the anchor flukes to dig in.

How much chain – well there is the million dollar question. The more chain you put down the better the anchor will hold. But chain is heavy and quite apart from the logistical problem of stowing all that weight on board a small boat there is the further problem of handling it. “All chain” warps are used on larger vessels where the crew have the advantage of a mechanical winch of some sort to haul it up again. A winch is not the sort of thing one often sees on board the size of rib that I come into contact with and trying to physically lift something like 5m of chain is about my limit! It is not just the lifting of the chain to the surface there is the problem of cracking the anchor out of the bottom. By the time I have lifted the chain there is little energy left in me to prise the anchor out! So a compromise is called for and somewhere between 2 and 5m will suffice for most ribs.

Our chain is going to be attached to the anchor warp, which begs the question how much rope? Yachting books may say 5 times the depth of water, but remember that figure is the sort of value for a cruising yacht bedding down for the night. Three times the depth may well be sufficient for our needs, and there is a pay off between chain and rope – the more chain you have the less rope you can get away with and visa versa.

Having sorted out rope and chain it is surely time to look at the anchor itself. Various patterns exist and all have their good and poor points.

The traditional “Fisherman’s Anchor” is the one everyone knows. The sort of thing that can be seen on Popeye’s arm this anchor tends to get a bad press as far as boating books are concerned. It is said to be a bad pattern because the flukes have a small holding surface and only one arm digs into the ground at any one time. However it is the anchor that I use on board my fishing boat which I anchor out there in screaming tides in the depths of winter to go cod fishing. It will cut through kelp and weed, will hook into rock and will dig into sand and mud. However it is an ungainly thing to stow unless the tripping bar is folded down. There is another disadvantage to be aware of if you use one somewhere that low tide will see your boat being left high and dry. Because one arm only is in the seabed the other will be pointing skywards and any boat that sits down on it at low water is likely to be pierced by the fluke – not the sort of thing to win you friends amongst your neighbours!

Bruce anchors are one piece anchors with no moving parts and hold well, being designed originally to hold oil rigs. On the down side they do not stow flat and can come to the surface clinging tenaciously to a heavy mini-boulder or a lump of wet and slimy mud!

Plough anchors are designed to dig deeper as the pull increases and are very effective, however the moving hinge can be a tad upsetting if your fingers are in the wrong place at the wrong time! A well known plough anchor is the CQR, so called because the initials spell out see-cu-re. CQR does not stand for Chatham Quick Release, as they told me in the Sea Cadets many moons ago, or any other variation on that theme!

Danforth anchors have large flukes that should provide a strong resistance against the sea bed. These flukes also present a resistance to the water as you lift the anchor so that it tends to “swim” away from you, or under the boat where it chips a lump out of your gel-coat!

Anchoring can be way of buying time in an emergency situation but the mechanics of the operation need to be well understood and second nature.

The boat need to be brought head to wind, or tide whichever is the stronger. In a strong tide especially once that anchor bites into the sea bed the warp will become “bar tight”. Anything that the anchor rope has taken a turn around is likely to be dragged over the side - so mind your legs. Should that turn be around something solid and fixed to the boat then your craft may be dragged sideways, or even stern first, into the tide – and that could have dire consequences!

In an offshore situation, with no fixed reference points visible, it may not be clear which direction the tide is flowing in and how strong the flow actually is. Such a scenario requires care as the anchor is lowered and action needs to be taken as soon as the sea bed is reached with the direction of the current being assessed before enough warp down there to enable the anchor to get a grip.

Most people anchor using the cleat bonded to the top of the bow tubes, or fix the rope to a u-bolt inside the boat and then lead it over the tube. I have to say I do the same in sheltered water but not out at sea. I prefer to form a loop in my anchor rope when sufficient has been paid out and then clip my painter, which is attached to the bow eye of the boat, into the loop. Now the boat is anchored off a strong point low down in the hull, and there is no rope digging into the front tubes. When the time comes to retrieve the anchor the joint between the anchor and painter can be brought to hand simply by pulling in the slack part of the anchor warp which is laid in the boat.

As a cautionary tale to finish this piece I will introduce a true story which, although it does not involve a rib, show the dangers involved with such a seemingly simple task as anchoring.

The incident revolved around Dennis, a stalwart of a boat club to which I belonged at the time and a highly experienced boat handler. Dennis and his wife set out one autumn Sunday to do a spot of fishing onboard their 5.5m cabin cruiser. Having arrived at heir chosen spot Dennis dropped the anchor.

The tide was running fiercely whilst a fresh breeze was blowing in the opposite direction, giving a choppy confused sea. Unfortunately the confused conditions lead to the anchor warp becoming entangled around the outboard leg and consequently the boat swung violently stern first into the breaking seas!

Waves started to come on board over the transom, and Dennis went aft to prove that the most efficient form of bilge pump is a bucket in the hands of a frightened man! The weight of all that water in the stern, plus that of Dennis himself, was too much for the boat and she went down like the proverbial brick. Luckily Dennis and his wife were plucked to safety by a nearby club boat whose crew had seen the accident.

So take care with that anchor – it can help save your life but can also put you at risk if you get it wrong!

Author: Dave Mallett runs Wavelength Training in Blackpool
Contact: info@wavelengthtraining.co.uk. You can visit Wavelength's website at www.wavelengthtraining.co.uk. Alternatively Dave can be phoned at T: 01253 876834 or M: 07867 555 129
 

 
 
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