Best Value For Money New Generation Anchor

This very experienced couple have posted an excellent video on the subject. The chap is hard to understand in places but it is very well worth sticking with https://youtu.be/_IdnW15fnns.
BTW - heand his wife built his own steel yacht and have for the last 30 years or so have been liveaboard cruisers - and are rarely in marinas
 
Noelex, thanks for the reference for Prof Knox' 2002 article in PBO. He clearly doesn't like the Britany! which puzzles me somewhat, as I normally use a 10 kg Britany and have found it to be a reliable anchor which holds well on softish sand or mud. (In particular it held well on soft mud when a 6 kg Delta failed to hold (wind about F6, in Newtown harbour, maybe Newtown has special mud!)). I normally bed the anchor in by running the engine (a mighty Yanmar 1GM) in astern - I don't know how much thrust this produces (must try to measure it) but it must be considerable - and on full power astern the boat generally doesn't move perceptibly. I don't know what to make of all this and am reluctant to abandon the Britany. ....
 
noelex said:
This 2002 article by Prof Knox is also worth reading:

http://www.stfeurope.com/pdf/Practical-Boat-Owner-2002.PDF
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Unfortunately Prof Knox used different materials for his rodes, with different elasticities. If you read all of his articles he defines which rodes he used. For some of his tests this did not matter as his comparative results for an anchor or a number of anchors tested with the same rode produces reproducible results. Other of his tests where he compares anchors using different rodes seems to result in erroneous results - and results that cannot be reproduced.

If you use an elastic, or more elastic, rode then some of the tension is stretching the rode, not setting the anchor. In the same way some people set their anchor with snubber attached - you are wasting engine power. By all means use a chain lock when you power set - don't use an elastic snubber. There a re videos illustrating this - don't follow the videos - they are simply an indication of ignorance. In Prof Knox results the most glaring example of this is where he compares hold of anchors of different weights and he develops results that no-one else internationally has ever achieved - basically his results are wrong. He suggests that some anchors if you double weight you more than double hold - no-one else has produced this result - at best if you double weight you might increase hold by 90% and for most of our anchors double weight and you will increase hold by 70%. This might also explain why some of his 'holds' are lower than others - effort is going into stretching the rode and thus reducing the hold.

He also mentions, or suggests, that hold developed can be extrapolated to hold when the yacht is yawing. This may be true for minor yaws, small changes of angle - but for a large change of angle - its invalid. Similarly when a yacht horses, in chop - the hold when set by the engine can be reduced. Similarly if the yacht is both horsing and yawing.

Any movement of the yacht, transmitted through the rode, will negatively impact the anchor - unless its a steady tension in the set direction. You can test this - touch any exposed part of the anchor when the rode is off the seabed and you will feel the anchor twitching. A moving anchor reduces the shear strength of the sand in immediate contact with the anchor - reducing hold - keep some of the chain on the seabed, bury some of the chain and you will reduce this effect.

If you are subject to yawing - reduce the yawing (maybe a riding sail) or set 2 anchors in a 'V' - then each anchor is set for the angle of the yaw. The other factor to priorities is to power set the anchor deeply so that the chain and shank are buried - both buried chain and a buried shank resist movement of the anchor that is subject to constant yawing. If your shank does not or is not buried - you increase your susceptibility to yawing.

Yachts yawing through 90 degrees, are quite common, and in anchorages with bullets coming in any and all directions the yacht can yaw through 180 degrees - it is very difficult to accept that a tension caused by wind at 90 degrees to the engine set direction can be the same 'hold' as a yaw through 90 degrees.

Professor Knox work is largely excellent but should be viewed with some caution.

Jonathan
 
blackbeard said:
I normally use a 10 kg Britany and have found it to be a reliable anchor which holds well on softish sand or mud. (In particular it held well on soft mud when a 6 kg Delta failed to hold (wind about F6, in Newtown harbour, maybe Newtown has special mud!)).
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The Brittany pattern together with the FOB variants are popular with French boats.

It is one of the so called Fluke anchors. Like the other Fluke anchors such as the Danforth and Fortress, it has excellent holding power in softer substrates, providing the direction of pull is reasonably constant. It seems to rotate slightly better than the other Fluke anchors, but it needs watching carefully if the direction of pull changes.

IoTWrF6.jpg
 
noelex said:
The Brittany pattern together with the FOB variants are popular with French boats.

It is one of the so called Fluke anchors. Like the other Fluke anchors such as the Danforth and Fortress, it has excellent holding power in softer substrates, providing the direction of pull is reasonably constant. It seems to rotate slightly better than the other Fluke anchors, but it needs watching carefully if the direction of pull changes.

IoTWrF6.jpg
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It is not clear in the image quite how this anchor was set - but interesting that its fluke/seabed angle seems higher than 30 degrees and the shank (and presumably chain) is starting to bury. I know of one FOB Light where the shank did not bend but snapped.

Most fluke anchors do well in soft substrates outperforming most other anchors (and this is especially so in mud - where fluke anchors (or at least a Fortress) will be factorially better than anything else). Most other anchors need watching in soft mud - its not that they are unreliable - they will not set at all.

Anchors are a compromise - there is no perfect anchor.

Jonathan
 
On yawing.
I don't agree that the susceptibility to yawing has anything to do with the anchor (any type), rather that this is to do with current, wind, boat shape and other surface factors. (Neeves above.. " If your shank does not or is not buried - you increase your susceptibility to yawing." )

What is important though is the ability of the anchor system to deal with yawing if it does occur.
Some anchors cope well (in some bottom types) with a changed or changing direction of pull, and others less well. Various techniques are possible to mitigate the effects of yawing on the anchoring system as mentioned.
I experienced a severe case of this twice in Gott Bay, Tiree, on two separate occasions. Good sandy bottom, good holding generally. A CQR pulled out often, after a good set (verified visually in the clear but cold water), but another modern anchor held well.

The comment above is one that we all sometimes forget.
"Anchors are a compromise - there is no perfect anchor." (Neeves above)
 
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MM5AHO said:
On yawing.
I don't agree that the susceptibility to yawing has anything to do with the anchor (any type), rather that this is to do with current, wind, boat shape and other surface factors. (Neeves above.. " If your shank does not or is not buried - you increase your susceptibility to yawing." )



The comment above is one that we all sometimes forget.
"Anchors are a compromise - there is no perfect anchor." (Neeves above)
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My poor English!

I meant increase the impact of yawing (caused by either the characteristics of the yacht, wind or anchorage) on the security of the anchor.

Apologies :)

Jonathan
 
noelex said:
A couple of other anchor tests that have included the Brittany style:

http://www.chainsropesandanchors.co.nz/image/data/PDFs/Yachting Monthly -Anchor Test Nov09.pdf

http://www.spade-anchor.com/IMG/pdf/2012_-_Tests_et_Comparatifs_ancres_-_VOILE_MAGAZINE.pdf
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When Alain Poireaud carried out his original tests against Spade anchors he used a 'plough hinged type' and two versions of a 'flat type' (with and without a bar) as comparators. It didn't take much effort to realise that he meant a CQR and a Britany (the correct spelling). Neither did very well http://www.spade-anchor.co.uk/sd_further_info2.htm
 
Its interesting that these two inventors (Poiread and Knox) both started out examining what was available and the deciding that the offering was good enough invented something better. Also interesting the similarity of the results - especially the CQR's ocsillating performance.
 
vyv_cox said:
Neither did very well http://www.spade-anchor.co.uk/sd_further_info2.htm
Click to expand...

Thanks for the link.

Both Spade and Prof Knox empasise that anchors should be roll stable. I also think this is very important characteristic that is often ignored with conventional anchor tests.

Spade mention a problem with the Fluke anchors (such as he Danforth and Britany style anchors) :

"Tests of American fluke (flat) anchors, in steel or aluminium, have shown a slightly different behaviour. Their designers have incorporated an extension to the hinge axis, creating a long strut each side of the two flukes, designed to prevent the corkscrew behaviour. Sadly, the strut not only fails to prevent the fault, but it also forms a trap on which the chain can readily entangle during major wind or current shifts.
Even worse, when these anchors drag on their sides they tend to stand up on three points: the end of the shank, the point of the lower fluke, and the end of the strut. In this stable position, they will slide under load, with almost no holding resistance, and - in every case where we observed this behaviour - they will never dig in again. (Please see Figure 2.)"


Prof Knox also mentions this same problem:

aGRHxY0.jpg



I have seen this issue, especially with a change in the direction of pull. I think this is major limitation of the fluke anchors which is a pity as they have otherwise such excellent holding in softer substrates.

kqSgPxs.jpg
 
Interesting how everyone knocks the CQR but its still used today, 80/90 years after it was introduced, used by Kim Novak till recently (in places many here will never visit). Used on Sunstone on a Pacific Ocean circuit. Yes - there are better - but some people find it reliable and have other things on which to spend their money. Also interesting the times a Fortress is knocked - they have sold over 600,000 units - yet people here swear its unreliable. Brittany are common on bow rollers in the Med, and we have 3 or 4 on yachts near our mooring - and there is no distributor here (confess - I've never used a Britany - so cannot comment other than observing how common they are).

Its difficult to believe the trolling in the face of the shear volume of evidence.

If these anchors were the disaster implied they would have died like the XYZ or the Hydro Bubble.

Jonathan
 
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noelex said:
Both Spade and Prof Knox empasise that anchors should be roll stable. I also think this is very important characteristic that is often ignored with conventional anchor tests.
]
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Roll stability is an issue when anchors reach their ultimate hold - for a 15kg CQR that's about 1t of hold in a decent sand seabed (which is where most anchors are tested). A 15kg CQR would be of a size recommended for a 35'-40' yacht - which will never reach 1t tension in the rode. So roll stability is interesting, academically, but not of much value to the user. The user needs to ensure the anchor is set - finish. Anchors will drag - not because they are not roll stable but because the vessel veers or horses and unseats the anchor.

Roll stability is a great asset but it does not stop an anchor dragging - new gen anchors do drag, they are supposed to be roll stable - so instead of looking at roll stability look at why anchors drag.

I would rather, instead of suggesting people test for roll stability, and for a new gen anchor of 15kg that means testing to 2t tension in the rode, I would rather anchor makers declared holding capacity data for their product in comparison with accepted competitive product.

To market a product without this data suggests, to me, that a manufacturer is not sufficiently confident in their product or have something to hide.

Jonathan
 
blackbeard said:
Noelex, thanks for the reference for Prof Knox' 2002 article in PBO. He clearly doesn't like the Britany! which puzzles me somewhat, as I normally use a 10 kg Britany and have found it to be a reliable anchor which holds well on softish sand or mud. (In particular it held well on soft mud when a 6 kg Delta failed to hold (wind about F6, in Newtown harbour, maybe Newtown has special mud!)). I normally bed the anchor in by running the engine (a mighty Yanmar 1GM) in astern - I don't know how much thrust this produces (must try to measure it) but it must be considerable - and on full power astern the boat generally doesn't move perceptibly. I don't know what to make of all this and am reluctant to abandon the Britany. ....
Click to expand...

SNSM lifeboats have Brittany anchors.
 
Neeves said:
Roll stability is an issue when anchors reach their ultimate hold - for a 15kg CQR that's about 1t of hold in a decent sand seabed (which is where most anchors are tested). A 15kg CQR would be of a size recommended for a 35'-40' yacht - which will never reach 1t tension in the rode. So roll stability is interesting, academically, but not of much value to the user. The user needs to ensure the anchor is set - finish. Anchors will drag - not because they are not roll stable but because the vessel veers or horses and unseats the anchor.

Roll stability is a great asset but it does not stop an anchor dragging - new gen anchors do drag, they are supposed to be roll stable - so instead of looking at roll stability look at why anchors drag.

I would rather, instead of suggesting people test for roll stability, and for a new gen anchor of 15kg that means testing to 2t tension in the rode, I would rather anchor makers declared holding capacity data for their product in comparison with accepted competitive product.

To market a product without this data suggests, to me, that a manufacturer is not sufficiently confident in their product or have something to hide.

Jonathan
Click to expand...

A comment in the French tests is that the CQR is handicapped by the weight of the hinge - which is weight too high up to facilitate the anchor resetting.
 
Sybarite said:
A comment in the French tests is that the CQR is handicapped by the weight of the hinge - which is weight too high up to facilitate the anchor resetting.
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So the 'auld alliance' did not extend to anchors :(

Many anchors do not re-set when 'dragged' - its why Morgans Cloud removed their recommendation for Rocna.

Interesting that the SNSM Lifeboats use Britanys - as the new Solent class seem to be using Spades (when on earlier boats they used Delta), no jingoism there then :)

And of those that condemn 'fluke' anchors - I'm sure they have an explanation for the longevity of Danforth, like CQR - almost 90 years old and still with us (somehow incorporated into the same sentence when they damn Fortress and Britany). Fortress, specified and supplied as a complete kit on Volvo yachts, used exclusively (well + Guardians) on IMOCA 60s (again in locations no-one here will ever visit). Horses for courses.

Anchors are a compromise - none are perfect, but they all have their place :)

Jonathan
 
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Just a small thought on anchor tests - reports tend to concentrate on the highest pull figures achieved by each anchor. In the real world, who cares if the anchor can hold a battleship one time in 20. What I want is one that will hold a decent pull every time. I prefer to compare the lowest figures in a series of tests.
 
Yes, good point.

The following are all important parameters that are largely ignored by traditional anchor tests:
Consistency
Performance with a change in direction of pull
Performance in poor substrates
Performance at realistic scopes


However, I think traditional anchor tests do have a role to play, but we need to look at a number of independent tests (I think the tests conducted by anchor manufacturers are much less valuable) and combine this with underwater observations of what the anchor is doing in the real world. If we add reports from experienced cruisers together with a technical analysis of the anchor design, I think we can seperate the better anchors from the "also rans".
 
"Interesting how everyone knocks the CQR but its still used today, 80/90 years after it was introduced..."

It seems to be an emotive topic, and especially interesting that many participants don't actually anchor that much. And given that safe anchoring is a combination of kit, use, and experience, missing one of those degrades the strength of argument.
I met a worst case example of this at the last boatshow I was at, an advocate for CQRs. But in the conversation it came out that some years he doesn't deploy it once. In those uses, it's easy to say "I can't remember the last time I had an anchoring issue with it - hasn't dragged for years".
 
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