Mantus vs Fortress for storm anchor

[Fortress]

Kettlewell & Bash,

I appreciate the input. Our late company founder, who was a lifelong and very adventurous boater with a 1,000 mile trip up the Amazon River, several Atlantic crossings, and a circumnavigation on his resume, said that "once an anchor breaks free from a sea bottom, it is oftentimes no longer an anchor....it's a massive ball with no remaining sharp edges in which to re-penetrate into the sea bottom.....and in this circumstance, re-setting is not possible."

This is one of the reasons why we note in our "Safe Anchoring Guide" literature that if you are expecting a wind or tidal shift (particularly in storm conditions), then its a good idea to set two anchors for maximum safety, which I think is part of Kettlewell's storm anchoring strategy.

It is certainly possible that the Fortress, with its two massive flukes, might become an even larger ball, so to speak, than other anchor types when / if it breaks free from the sea bottom, and in turn, it is less likely to re-penetrate.

Simply stated, there might be more sea bottom clinging to the Fortress that has to be removed first before it becomes a sharp anchor again.

Additionally, we will certainly acknowledge that a denser, narrower, single fluke anchor type has an advantage in certain thick or hard bottom types, i.e. grass / weeds (as Bash mentioned) and rocks.

Sww914, thank you for the kind words.

[Fortress]

Originally Posted by Mike OReilly

Not dissing Fortress at all. I think they are great anchors. I will likely be getting the FX-37 based on the comments here. But I would do so knowing that getting a proper set will be potentially more challenging.

Mike, no dissing taken. In deeper water, minimal scope, boat falling back quickly, and in some bottom types (as mentioned previously), the lighter Fortress might take longer to get to the bottom and set.

But with the recommended scope & chain, and in any kind of common softer bottom (sand, mud, clay), the sharpened Fortress will head straight for China and bury deeply in no time.

[noelex 77]

Originally Posted by Fortress

it is our firm contention that a properly set and well-buried Fortress anchor, with its two massive precision-machined and sharpened flukes, is not more likely to break free from a sea bottom during a wind or tidal shift than other anchor types, particularly those with far less surface / resistance area.

Brian let me say you have always been very honest about the strengths and weakness of your companies product, but I do have to disagree with you about the above.
When I dive and watch anchors the Fortress (and Danforth) has a failure mode with large wind shifts that does not occur on other modern anchors. It only hapens with large, abrupt, changes in direction, in harder substrates, but under these circumstances the anchor can pivot on the end of the fluke and break out. In most cases it will reset to the new wind direction leaving the owner unaware what has happened. Hence the problem is much better seen diving, observing the anchors behaviour.
With a strong gust at the wrong time just as breaks out it will drag and then like all anchors risks not resetting. This is what causes the (admittedly rare) tales of Fortress dragging with a wind shift.
There is also some risk of the flukes getting jammed with debris and locking.

Other modern anchors do not do this. They remain completely buried. (Although they often develop a list as they rotate).

The Fortress is a great anchor, it has properties that are not matched by other anchors. For a second anchor that may need to be deployed by dingy the Fortress has no equal.
If they dont already have one it should should be on the wish list of every crusing boat, but there are better choices for the anchor at the bow.

[Andrew Troup]

Noelex

The interpretation of the words "Properly set and well-buried" might explain the discrepancy between Brian's claim and your experience.

As the rest of that post implies, (and having read more detailed explanations of the steps taken to recover the Fortress anchors tested against severe overloads) I'm well prepared to believe that a Fortress anchor in a suitable bottom can bury to a depth from which it would require a scuba diver with a venturi excavator to retrieve.

If one were merely to tug on it at 90 degrees, with the same load which (eventually) set it to that depth, it seems plausible to me that it would not budge.

[noelex 77]

The problem is much more likely to happen in harder substrates, as the Fortress rotates the long stock is forced deeper as the anchor develops a list. If the deep substrate is very hard this will catch the stock. The whole anchor then pivots around this point and the anchor is forced to the surface.

It is difficult to sometimes to tell the set of a flattish anchor like the Fortress. It can disappear, but still not be set very deeply although with the hard sand often found in the Med a Fortress anchor that has disappeared (even if only just below the surface) is about as deep as you will burry it under engine force alone. I have seen Fortress anchors break out with a change of wind direction when set like this.
Generally the anchor will reset anyway, but its more reassuring t have an anchor that always remains buried during the change of direction

On my own anchor I have a small float attached and the amount of rope showing gives me a good idea how deeply its buried even when no part of the anchor is visible.

[Cherp]

Met a couple in Indonesia who had a Fortress as the primary on a 50ft Beneteau. They had been using it for months. Trusted it implicitly. We have a Sarca Exel. But I am also impressed by the Fortress and it's lighter.

[Kettlewell]

I am absolutely sold on the Fortress as a secondary anchor, and I often use one set in such a way that the direction of pull will not change greatly. When I was down in the eastern Caribbean, where the wind blows from the same direction for days or weeks at a time, I found the Fortress was often an excellent anchor. In New England, where one's boat may rotate around the compass several times during the day, with varying wind strengths from all directions, most of the time it is better to have an anchor that has very little in the way of protrusions that can catch the chain. I have brought up Fortress and Danforth anchors that looked like a cat's cradle of chain after some of these experiences--completely wrapped up in the chain. Frankly, that is one reason I have moved away from the Bulwagga as my primary. Even though 90% of the time all three flukes get buried enough to prevent the chain getting caught in windshifts, that 1 out of 10 time when the chain gets wrapped is usually during the 2 am thunderstorm wind shift. You can get the same problem down in the ICW or the Bahamas, or other areas where you anchor in reversing tidal flows. Even without wind, you circle your anchor a couple of times per day, leading to the potential for wrap ups.

[JonJo]

Our experience with a Fortress is that as the flukes dive the shackle end of the shank remains visible, eventually the crown dives and then the shackle end of the shank. We mark the chain at about 2 metres (from the shackle end) so we know when we lift the anchor when it will appear - so if we can see the chain mark, we know where the shank end is. Once the anchor has that level of 'dive' and given the huge depth of dive of the flukes the chance of it lifting from the seabed is minimal. With a 90 degree turn it simply swivels (it is set so deeply).

The idea that a Fortress will not dive as deeply as another anchor seems to lack foundation (particularly as no-one is able to test a Fortress against another in the same conditions - unless under 'laboratory' conditions). The Fortress has no impediment to diving, it has no roll bar, it has no weight in the toe. Virtually every anchor I can think of has a higher resistance to sea bed penetration. The Fortress has no cross sectional area to inhibit diving, of any anchor it is as near a knife in butter as you can get. A Rocna has a thick weighted toe and roll bar, a Spade and Excel have weighted toes so the idea that one anchor will dive and set better seems to lack any basis. Every anchor test I have ever seen has always remarked on the ability of the Fortress to set and set deeply. This might reflect testing seabeds - but people like to expose weakness and I have yet to see anyone find a seabed (other than heavy weed) that will show any inability of the Fortress to set as well, if not better, than any other anchor. In heavy weed a Fortress might meet defeat - but so will most other anchors (and there is evidence that the sharp flukes of a Fortress will penetrate where others fail).

If the Fortress has a weakness in terms of setting it is that it sets so well it can be very difficult to retrieve. But you cannot have it all ways. To my mind an anchor set so well it saves your yacht (and the anchor needs to be abandoned) seems a small price to pay.

If a Fortress has opportunity to catch something into its fluke to stop it resetting is another of those old wives tales that is as valid for a Fortress as any other anchor. It might happen,but equally a roll barred anchor can clog with something on the seabed, a towel lost overboard, a water logged piece of wood, a kelp stalk. Block your anchor with a loose bit of coral is as damaging to a Fortress as a Rocna, or Excel. Whether one particular design, of anchor, might concentrate that process - that is a decision for the owner - but a flat fluke is neutral, a plough casts the debris aside and the concave?

We see first hand negative stories of other anchors, CQR (dragging), Bruce (needs to be bigger, does not penetrate hard seabeds), Rocna (clogging). There are whole hosts of anecdotal negative stories of the Fortress that seem denied by the fact the anchor has been around for 25 years yet the negative stories are virtually never first hand experiences.

[capngeo]

My Primary is an old Bronze CQR..... and is only the primary because the bow davit will not fit my Fortress! I carry an FX-37 on a rail mount on the stern. I have found the CQR with an all-chain rode is often outperformed by the Fortress on a Nylon rode. The exception is when trying to anchor in a fast current with the engine out.... The Fortress tended to "sail" in the current and never set.

I have survived hurricane winds 3x in Key West at anchor. The Fortress was always used as primary, and I always used a stern hook as well. BUT the set-up was done in advance, hand set with SCUBA.

[barnakiel]

I cannot speak for Fortress (do not have one) but I can say that all Danforth types I have used had the same problem - they were better NOT veered, or else. The same problem was with our CQR type.

But or Bruce type can be veered and it will keep on holding us just fine. I believe some modern anchors (Spades, Rocnas, Mantuses, Brugels, etc.) can also be veered.

But now if you ask me which anchor held better in the blow, I will admit it was the Danforth type - while the Bruce type dragged slowly, but noticeably. OK if there is open water beyond you, but what if there is that rock? I believe Danforths (weight for weight) develop very respectable holding power.

Also, Danforth type, once in, can be used with pretty short scope. Big plus in many situations.

So to say no toy is perfect and as long as one is aware of limitations of each, they are likely to sleep fine.

b.

[S/V Alchemy]

Debates such as this (and this one's unusually polite, respectful and informative) make me question not whether Fortress or Mantus or Rocna are "best all around", but whether it is wise to consider that there can be a "best all around", and if not, should we stick to the term "primary" meaning merely one anchor?

I own and like the Fortress...but I still carry a CQR and even a Bruce. Hell, there's a fisherman's in a canvas sack down there somewhere. If one prefers to use Anchor Style X because it's good 90% of the time in 90% of the grounds, I suppose it's one's primary. If it's light like an aluminum Spade or any Fortress, that's security and "gravy" in one package. If you think "man, we are going to go in circles with 10 gusting 35 all night...maybe I should try Anchor Y"...there isn't going to be a "loyalty cop" to accuse you of "cheating on your primary".

You do what feels right, and if space and ability to carry the weight allow, two "primaries" in differing styles probably isn't a bad thing. I like the Fortress because I can see it as a primary on one of my two boats, and a secondary/lunch hook/storm anchor on the second, larger boat.

Kind of a win/win, really.

[toddedger]

All of the new style anchor have trouble when the bottom gets hard to penetrate. If you look at the sail magazine test you will see everyone suffered when the bottom had shallow sand and got harder underneath. The one thing the Rocna has over the others is that place to hook a second anchor to it. If you know you have a big storm coming, hook the Fortress on the back of your Rocna. That will give you three points to dig in the hard stuff.

[Mantus Anchors]

Mantus Resetting Video

https://www.youtube.com/watch?v=KlGwv7mAXvQ

[robert sailor]

Originally Posted by Mike OReilly

I tend to agree ... to a point. Our bower is a 55lb rocna. Perhaps not the meanest one we could have, but getting pretty close considering our all-chain 3/8" rode. I've never dragged yet once it's been properly set, and that includes weathering 50knt (sustained) blows.

When I'm out we anchor all the time. And being up here on the north shore of Lake Superior, I'm all too familiar with non-predicted squalls and thunder storm.

Thanks for the tip Barn. I'll look into stowable spades.

55lb Rocna is an excellent primary anchor for your boat!

[JPA Cate]

Originally Posted by robert sailor

55lb Rocna is an excellent primary anchor for your boat!

Mike has a Rafiki 37. I think a 55 lb. Fortress would be a huge PITA to store and use. A heavy Mantus that is able to shuffle with the wind shifts, I think would be a better deal, right there on the bow roller, and ready to go and do it's job. He has a heavy Danforth, which will provide him with additional holding power, should he need it.

Furthermore, with his plans to go to the med, we have all seen pictures of noelex's big mantus digging in, even where there is fairly shallow sand over a harder substrate.

Just my two cents' worth.


Ann