Best Practice -- Ground Tackle for Larger Motor Yachts

[Dockhead]

I am presently cruising on a friend's recently acquired 30m motor yacht in SE Asia. I have to say it's a very pleasant experience, rather different from cruising on my boat, but I sure am glad I'm not paying the costs of it, particularly the salaries of the large crew required nor for the 100 liters/h of fuel burned at economical cruise speed.


The owner is an old friend and shipmate of mine who is a good sailor himself. But he is asking me for a lot of advice I'm not qualified to give. For one thing, what to do about his ground tackle? The vessel is equipped with a couple of imitation CQR's, badly made out of stainless, and hardly bigger than the anchor on my boat. Obviously these need to go, but what is best practice for a vessel of this type, 30m LOA, plenty of windage, 175 tonnes displacement? I know that you can't use a simple linear scale with what we have.


Vessels like this are typically run from harbor to harbor, often without even the owner being on board at sea. But my friend is not like this, and I can well imagine his testing the limits of his ground tackle.

[Uncle Bob]

Originally Posted by Dockhead

I am presently cruising on a friend's recently acquired 30m motor yacht in SE Asia. I have to say it's a very pleasant experience, rather different from cruising on my boat, but I sure am glad I'm not paying the costs of it, particularly the salaries of the large crew required nor for the 100 liters/h of fuel burned at economical cruise speed.


The owner is an old friend and shipmate of mine who is a good sailor himself. But he is asking me for a lot of advice I'm not qualified to give. For one thing, what to do about his ground tackle? The vessel is equipped with a couple of imitation CQR's, badly made out of stainless, and hardly bigger than the anchor on my boat. Obviously these need to go, but what is best practice for a vessel of this type, 30m LOA, plenty of windage, 175 tonnes displacement? I know that you can't use a simple linear scale with what we have.


Vessels like this are typically run from harbor to harbor, often without even the owner being on board at sea. But my friend is not like this, and I can well imagine his testing the limits of his ground tackle.

Send an inquiry to Rex at sarca anchors and I am sure he will offer advice!

[Dockhead]

So digging a little deeper into this, I see that Lloyd's has a formula for "Equipment Number" which is the basis for sizing not only anchors but other gear:

Equipment Number calculation - MarineWiki

Don't know if this is fully applicable to a vessel of this size, but maybe a good starting point. Rocna give anchor recommendations based on EN:



https://rocna.com/fitment-guide/

[ranger58sb]

One approach might be to compare manufacturer recommendations for ALL of the common new generation anchors (including SuperMAX, which doesn't always get "newgen" respect) plus Fortress... if any of those make something large enough for that length/windage/displacement.

-Chris

[Spot]

So, they don't check that stuff on the drawing board or in the shipyard or whilst commissioning or during surveys for sale or insurance purposes?

[Woodland Hills]

Originally Posted by Spot

So, they don't check that stuff on the drawing board or in the shipyard or whilst commissioning or during surveys for sale or insurance purposes?

No, “they” don’t, whoever “they” might be. “You” the boat owner is responsible for that. The same way the owner is expected to obtain a tender suitable for her own needs. A surveyor might comment upon suitability of ground tackle during pre-purchase inspection or he may not, it depends upon the buyers instructions. Normally the surveyor will only comment upon condition, not size or brand.

[a64pilot]

A lot of larger motor yachts can’t fit many anchors, due to the way they store anchors. Most don’t have a bow sprit that can hang almost any anchor design on.
So how does the Yacht your own stow it’s anchors?

Most larger motor yachts go from one Marina to another, and as you say are repositioned by crew without the owner and never really anchor, but I saw many doing so in the Bahamas as their draft wouldn’t let them in close.
My assumption is with crew always aboard when they drag it’s no big deal, up-anchor and reposition

[Breaking Waves]

Originally Posted by Dockhead

30m motor yacht in SE Asia ..... For one thing, what to do about his ground tackle? The vessel is equipped with a couple of imitation CQR's ...... what is best practice for a vessel of this type, 30m LOA, plenty of windage, 175 tonnes displacement?

A couple comments:

I presume the vessel has a pro captain. Your friend should ask and trust his captain (if he does not trust him he should either mentor him in further education/development or get a new one). This is a tricky size because it is big enough to potentially cause serious issues for an inexperienced/unskilled captain, but small for where a skilled/experienced captain would want to be in his career unless the owner is a truly good boss. With this sort of vessel, you have to build a team and all that requires - for the owner, building and managing the human side becomes more important than technical involvement in the vessel.

If the captain is unsure, he should be self-confident enough to say so (and your friend as a good boss should encourage this). In which case they should hire an MCA surveyor for a small fee to assess the situation. The MCA surveyor will look at EN as a minimum and upsize from there depending on the owners' plans.

The scaling from small recreational vessels to +30m vessels is not straightforward, and 'Plow" designs are quite common and quite successful in the huge designs. Manson, for instance, does not really suggest their 'next-gen' design for these size vessels. The two 112'ers I am engaged with both have huge (more than EN sized) plows as their main anchors, and both have big fortresses as secondary anchors (because they are really the only ones in this size you can move around without a workboat and crane) - they both do high latitude cruising and anchoring. To my knowledge, they have only dragged twice, once on a bad bottom and another time on human (captain) error - trying to satisfy the owner by fitting into too-small space with not enough scope.

The 'operational practices' on these sorts of vessels also don't 'scale' from our recreational vessels. They have full pro crews. They should have an anchor watch at all the times, although many do not; but certainly should anytime winds are over say 30 kts. Running the engine (and using thrusters) to take loading off ground tackle, and potentially to avoid vessels dragging by them, should be a part of the normal skills tool kit. Reanchoring should be a 'no fuss/no muss, the owner should almost not even notice' sort of skill set.

[Dockhead]

There is enough crew to have a constant anchor watch, but I don't think that mitigates the problem. Anchor dragging in snotty weather is a terrible thing, and can be dangerous.



The classification societies seem to have some guidelines, but I just cannot imagine what guidelines could possibly have been fulfilled with the toy anchors on my friend's boat.

[Breaking Waves]

Originally Posted by Dockhead

There is enough crew to have a constant anchor watch, but I don't think that mitigates the problem. Anchor dragging in snotty weather is a terrible thing, and can be dangerous.

anchor watch does certainly 'mitigate' the problem, but sure/certainly/absolutely you want to avoid dragging and should have the correct equioment



The classification societies seem to have some guidelines, but I just cannot imagine what guidelines could possibly have been fulfilled with the toy anchors on my friend's boat.

It may well not have been fit with EN conforming gear. It is (I believe) only legally required if the vessel has a commercial class certificate. Although, I would guess many insurance companies might find fault if the gear was grossly below EN. is possibly a bit tricky to do an 'accurate' EN number calculations, but it is not hard to do a back of the envelope one and see if the existing tackle is in the ballpark.

Again, honestly, the captain should be asked - has he been? Does he think the gear is undersized?

.............

[Dockhead]

Originally Posted by Breaking Waves

A couple comments:

I presume the vessel has a pro captain. Your friend should ask and trust his captain (if he does not trust him he should either mentor him in further education/development or get a new one). This is a tricky size because it is big enough to potentially cause serious issues for an inexperienced/unskilled captain, but small for where a skilled/experienced captain would want to be in his career unless the owner is a truly good boss. With this sort of vessel, you have to build a team and all that requires - for the owner, building and managing the human side becomes more important than technical involvement in the vessel.

If the captain is unsure, he should be self-confident enough to say so (and your friend as a good boss should encourage this). In which case they should hire an MCA surveyor for a small fee to assess the situation. The MCA surveyor will look at EN as a minimum and upsize from there depending on the owners' plans.

The scaling from small recreational vessels to +30m vessels is not straightforward, and 'Plow" designs are quite common and quite successful in the huge designs. Manson, for instance, does not really suggest their 'next-gen' design for these size vessels. The two 112'ers I am engaged with both have huge (more than EN sized) plows as their main anchors, and both have big fortresses as secondary anchors (because they are really the only ones in this size you can move around without a workboat and crane) - they both do high latitude cruising and anchoring. To my knowledge, they have only dragged twice, once on a bad bottom and another time on human (captain) error - trying to satisfy the owner by fitting into too-small space with not enough scope.

The 'operational practices' on these sorts of vessels also don't 'scale' from our recreational vessels. They have full pro crews. They should have an anchor watch at all the times, although many do not; but certainly should anytime winds are over say 30 kts. Running the engine (and using thrusters) to take loading off ground tackle, and potentially to avoid vessels dragging by them, should be a part of the normal skills tool kit. Reanchoring should be a 'no fuss/no muss, the owner should almost not even notice' sort of skill set.

The captain is a very good seaman and a very good guy. I've spent a lot of time with him. He is similarly perplexed about the ground tackle issue. He has spent his whole career driving motor yachts from port to port and is smart enough to recognize his own lack of experience with anchoring.


The MCA surveyor is a good tip. I'll suggest that.


I don't think this vessel is going to high latitudes, but my friend will be pushing the limits, going to remote places, nonetheless. I'd like to see him well prepared for that.

[wayne.b]

Originally Posted by Dockhead

I am presently cruising on a friend's recently acquired 30m motor yacht in SE Asia. I have to say it's a very pleasant experience, rather different from cruising on my boat, but I sure am glad I'm not paying the costs of it, particularly the salaries of the large crew required nor for the 100 liters/h of fuel burned at economical cruise speed.


The owner is an old friend and shipmate of mine who is a good sailor himself. But he is asking me for a lot of advice I'm not qualified to give. For one thing, what to do about his ground tackle? The vessel is equipped with a couple of imitation CQR's, badly made out of stainless, and hardly bigger than the anchor on my boat. Obviously these need to go, but what is best practice for a vessel of this type, 30m LOA, plenty of windage, 175 tonnes displacement? I know that you can't use a simple linear scale with what we have.


Vessels like this are typically run from harbor to harbor, often without even the owner being on board at sea. But my friend is not like this, and I can well imagine his testing the limits of his ground tackle.

===


You really have to evaluate the whole ground tackle system - windlass(s), chain, chain locker, hawse pipes (if any) and anchor. Just for openers, you'd really like to have as much heavy chain as the windlass and locker can accommodate. Yachts of that size typically have to anchor in outer harbor areas in deeper water, frequently 15 to 20 meters or greater, implying a need for at least 120 to 160 meters of 13 to 16 mm chain, preferably stud link to minimize hockling in the chain locker. Any of the modern anchors like Rocna or Spade will do just fine if the boat can fit them on the bow, otherwise you'll need navy style fluke anchors which can feed up into the hawse pipes and lay alongside the topsides. I'd consult with the anchor manufacturers for weight recommendations but 150 to 200 kg would be a good starting point if the windlass can handle it. I'd also recommend several Fortress FX-125s carried dis-assembled for backup and special situations, along with several hundred meters of 25mm nylon rode, miscellaneous shackles, etc.

[roland stockham]

At that size a weight I would expect you to be looking at ship pattern anchors that stow in the hause pipes like a big ship. Out of the the range for yacht gear. The anchor makers will have recomendations for cable which will likely be substantial cross linked chain and in the hundreds of meters. Ships use reletively small anchors but long lengths of heavy chain so the issue will probably be chain stowage and windlasses.

Best place to look at examples ang get advice may be to find a local tug skipper with a tug of similar size and ask what they carry. Alternatively have a look at the regs for required anchors on small ferries under some reliable flag like UK or Canada.

[Breaking Waves]

just fyi . . . . the 112'ers are using 350-400lb plow main anchors.

but I'm not sure if that's at all helpful because their EN numbers would be very different from your powerboat case (I presume much greater windage with the powerboat) and their cruising itinerary is different and there may well be stowage considerations.

The 112'ers typically use a single main anchor. I know much less about it but my observation suggests +30m powerboats often drop two anchors.

[Paul Howard]

It is not just the anchor, but the whole system that needs review.
Chain size?
Shackles and connectors?
Bow rollers and carriers?

Windlass capacity?
I was once the Production Manger for a boat building company that built a model 82ft LOA, 200 tonnes displacement.
We had twin hydraulic windlasses with rollers sloping down channels inset into the foredeck and fixed seawater spray nozzles to clean the chain before it came over the rollers.
The sloping channels prevented anchor mud from flowing down the shear of the deck to mid-ships. Otherwise one would have to spray down the deck when raising anchor