Fortress Anchor in Mud

[cheoah]

If this happened while I was trying to set a Fortress, I would slow it down, pay out scope as I drifted down slowly, and lock it down at 7:1 - more as conditions dictate. I'm in deep mud country here too; we use it as an emergency anchor in the normal position with the moderate angle.

The Delta seems way undersized, I would want a bigger anchor as a second - or primary anchor really - and the fortress would not be a go-to anchor in my conditions with mud or sand, and reversing currents. Perhaps it is the best choice for your area, but I would probably bump it up a size, as everything is riding on it.

[Fortress]

Hi Ron,

The advice you have received from the other posters on this issue has been superb. I agree that the most likely issue is the 45° angle setting, which should only be used in very soft, soupy, silty mud bottoms (i.e. Chesapeake & SF Bays) which I do not believe you have in those northern areas.

If the anchor is set at the 45° angle and the bottom is a harder type of soil, then the anchor will not penetrate and it will skip along the bottom.

This is important information for us to hear back, as it indicates that we have to do a better job of explaining the pitfalls of using the 45° angle setting in our literature, other than just putting "Soft Mud Anchoring Only" labels over the hole openings in the crown where this angle adjustment is made.

The upside of the 45° angle is that it will dramatically increase holding power in a soft mud bottom, and while the Fortress is one of the only pleasure boat anchors with the adjustable shank/fluke angle (I think the Super Max is another), the advantage of the wider shank/fluke angle is common knowledge among large anchor manufacturers such as the US Navy and Vryhoff.

Below is a page out of the Vryhoff anchoring manual which mentions and illustrates the above.

Safe anchoring,
Brian

Fortress Marine Anchors

[RonaldJJames]

Thanks again for the comments. Of course I failed to mention, perhaps the most important part of my situation - there is a lot of weed here (in mud). So my feeling is that the Rocna is heavy enough to penetrate the weed but the Fortress is just sliding on top of them. I haven't yet had a chance to try the 32 degree setting but will do so when I can.

[Ziggy]

Originally Posted by RonaldJJames

Thanks again for the comments. Of course I failed to mention, perhaps the most important part of my situation - there is a lot of weed here (in mud). So my feeling is that the Rocna is heavy enough to penetrate the weed but the Fortress is just sliding on top of them. I haven't yet had a chance to try the 32 degree setting but will do so when I can.

In weeds, anchor weight is very important. I don't think a Fortress will work, for the reason you mention. I would think a heavy Rocna, Manson, or Bruce would be much better. I would go up one size on the Rocna (to 15 kg).

[Dulcesuenos]

We have a similar sized cat _we use a 35 delta for storm anchor and questionable holding and a 25 Manson the rest of the time. She came with a large fortress I may never use. If it'd so difficult to set I would be worried about it resetting middle of the night with a strong reversing tide and wind .

[noelex 77]

Originally Posted by Dulcesuenos

We have a similar sized cat _we use a 35 delta for storm anchor and questionable holding and a 25 Manson the rest of the time. She came with a large fortress I may never use. If it'd so difficult to set I would be worried about it resetting middle of the night with a strong reversing tide and wind .

If you have a storm the wind will override the effects of the tide and you will stay in roughly the same direction. A large Fortress can be a very good storm anchor, providing the strong wind is from a reasonably onstant direction. Your other two anchors the 35 Delta and 25 Manson supreme ( I presume this is what you mean, Manson make a lot of anchor types) I would have expected to have similar holding in many bottom types.

With very severe conditions the Fortress can work well in tandem with the Manson Supreme, particularly as the Manson is on the small side for your boat and storm conditions. The light weight of the Fortress means its easy to deploy and retrieve the tandem arrangement. This would leave the Delta as a spare if you have to cut away your main anchor.

Anyway just a few thoughts. It pays to think about strategies before hand.

[Mark Johnson]

Originally Posted by RonaldJJames

I have a 32' sailing catamaran (a Tomcat 9.7). The boat is light - she weighs 7000 - 8000 lbs, although being a cat, she does have high windage.
Before taking delivery I researched various anchors and chose a Fortress FX16 as my primary anchor and a Delta 10 as my storm anchor. Each has 20' of 1/4" chain and 200' of 5/8" nylon rode. Both of these anchors were sized using the respective companies sizing guides, Fortress Marine Anchors and Sizing Chart » Rocna Anchors.

I've been cruising Georgian Bay, Lakes Huron, Erie and Ontario and am currently in the 1000 Islands. Whenever I anchor, I back up slowly as the rode is let out and then I motor hard astern to ensure the anchor is well set. SO far, I'm very dissapointed with the Fortress. We're anchoring a lot in mud and despite setting the flukes to the 45° mud position and installing mud palms I cannot get this anchor to set. Backing up with even moderate power (I only have 20hp anyway) just causes the anchor to drag. I did get the anchor to set nicely on a sandy bottom once, but never in mud.

My understanding was that this anchor is good in mud. Am I doing something wrong? I'd be very interested in others comments on this anchor.

Thanks in advance.

Ron James

Ron,

On our Searunner 34 we use a delta 35 as a primary, and 3 successively larger Fortresses as back ups. They do hold well in mud, but if you have soft mud, it can be tricky getting them down below to the harder mud underneath.

One point about their use as a primary... NO brand of "lightweight" = "Danforth" type, should be used "by itself" overnight, or in any situation where the wind and / or current may reverse.

These types of anchors have the best holding, pound for pound, but with a reversing pull on the rode, even when burred, when strong enough... they pull out of the bottom. When this happens, the hinge can EASILY be defeated by mud, a stick, a shell, or a beer can. SO, they do NOT necessarily re-set at all.

The single head type, however, (Delta, Rocna, Spade, Manson), do not usually pull OUT of a "good" bottom, when the load reverses. When the new wind / current strength is sufficient, these types work themselves around to the new direction, while remaining buried. IF they do pull out, they have a MUCH higher chance of re-setting themselves. (EXCEPT IN THICK GRASS) No modern anchor is reliable in thick grass!

Lightweights are GREAT for short term storm anchors, to make a hurricane mooring, or to oppose the primary, "Bahamain moor style". Their load can veer 90 degrees to either side of the original set ONLY.

The higher holding power of the lightweight anchors, (pound for pound), is irrelivent. For your primary, you need an anchor that reverses RELIABLY. This is why 99.9% of the worlds serious cruisers use one of the mentioned single head "plow shaped" types.

This is based on > a dozen hurricanes, including many successfully anchored for, as well as thousands of nights spent "on the hook", in clear water, where I could see ALL of the anchors around me.

I know... lightweight type anchors can not repeatedly reverse themselves with the reliability of the plow shaped types... not even close!

If any manufacturers say otherwise, they're trying to sell you their anchor.

BTW.. Manufacturers tend to undersize their charts. You should always anchor for AT LEAST 50 knots of wind, which is very common. The charts are for a fairy land world where this never happens! For your boat, in say... a "Delta", this means the 35#er, like ours. I pulled ourDelta in hand over hand, (with 1/4" HT chain), for most of 16 years.

Also... IF you use a boatlength long bridle, (tied to the rode with a rolling hitch), as ALL multihulls should, it cuts the load on the hook by > 50%. It is the monohull style "sawing around" that creates such huge loads. I can physically pull our boat forward in 35 knots of wind, IF pointed STRAIGHT into the wind, which the bridle assures. If it falls off 10 degrees, not so! Most multihullers use TOO SHORT a bridle.

M.

[Fortress]

I have heard conflicting reports on the performance of our product in weeds, as some customers have said that the sharpened flukes of the Fortress are able to slice through the weeds and bury into firmer ground below, while others have said that the anchor will penetrate, but will then quickly foul and pull the weeds out when loaded, which can possibly happen with any anchor.

That said, I concur with Ziggy in that a heavier dense anchor with a narrow single fluke blade might slice through and dig into a weed bottom more effectively.

Regarding anchor re-setting capability, 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.

This contention is based upon the opinion of a 40+ year US Navy soil mechanics and anchor design expert, the 25 years of testimonials we have heard from Fortress owners all over the world, as well as from independent test results.

One such independent test was done by the Sailing Foundation, in which they conducted straight, then 90°, and finally 180° pulls on the anchors tested. A 24 lb Fortress model FX-37 held to the maximum of 4,000+ lbs in the three pull directions, and no other much heavier steel anchor (i.e. Bruce, CQR, Davis, Delta, Luke, Max) was close.

All of that noted, we will readily acknowledge that sailboats oftentimes do not have the engine power to back down hard enough on the more massive Fortress anchor to bury it deeply, and therein lies a key issue in how it performs (or not) during off-center loads.

So in essence, I am in agreement with Mark on this.

Here's an interesting comment from the Sailing Foundation test which illustrates this point:

The Fortress set so deep that the rode had to be hauled in to 1:1 and significant power applied to rode by the 83,000-pound tug to break it free. It is doubtful that a sailboat would have windlass power to break it out. Perhaps large primary winches or a rising tide might be adequate. However, it is also doubtful that a sailboat could have set the anchor that deep in less than a full hurricane.

Our company founder/owner, 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 is 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, its a good idea to set two anchors for maximum safety.

Otherwise, as Mark emphasized, a large heavy plow type might serve your sailboat better.

Safe anchoring,
Brian Sheehan

Fortress Marine Anchors

[noelex 77]

Brian I think you provide a very balance view of your companies product which is very welcome.
I also think every crusing boat should have a Fortress anchor it has attributes that are just not seen on any other anchor.
I have also recently purchased one of your very small Gardian anchors for the dingy and is a great solution to an anchor for the tender.

However I have to disagree with some of what you say when the Fortress is subject to a large change in the direction of pull. I have seen the effect underwater. The problem is that if the direction of pull changes dramatically the anchor develops a bank like all all anchors do. The long stock of the fortress is then forced deeper down in the substraite, on one side, if this puts it into firmer ground the stock is locked and the whole anchor pivots around this point which forces it to the surface.

If you ever get the chance to test the anchor with a flattened stock rather than the thin round section I believe this would be an improvement and would make a great anchor better. A flat horizontal sectional of aluminium with a sharpened leading edge would be ideal.
It would be an easy "upgade" that could be made available to existing owners.
Anyway feel free to use the idea (or file it in the round metal filing cabinet below every desk )

[Cheechako]

Originally Posted by RonaldJJames

Thanks again for the comments. Of course I failed to mention, perhaps the most important part of my situation - there is a lot of weed here (in mud). So my feeling is that the Rocna is heavy enough to penetrate the weed but the Fortress is just sliding on top of them. I haven't yet had a chance to try the 32 degree setting but will do so when I can.

That changes things.... even the Danforth... which is mostly a heavier Fortress is not noted for easy use in weeds. I would us a different anchor there.

[Fortress]

Noelex, thanks for the kind words, insight, and product suggestion. I know the stock (narrow round rod) takes a fair amount of load as the anchor is being pulled and we would have to be careful not to weaken it in any way.

Cheechako, good point. The old Fisherman type anchor comes to mind, as it has often been said to be a better performing anchor in weeds. Below is an image of one that is outside our company headquarters.

She's a beauty but I think she is starting to show her age!
And she's a bit heavy. Last time we moved her, three strapping young men were required!

[cheoah]

There is a compromise in every anchor; I agree that Fortress is a great one to have stored away for the right times. In mud, with consistent winds from a storm event, it will likely outperform the plow types I usually deploy. Before I set a good storm mooring, I used a big fortress for hurricanes, set in tandem with a plow-type.

In the end, chafe is the equalizer.

Ronald, do you carry a Rocna, or a Delta? Either one would do, but consider getting a bigger one, minimum 25 lbs -- bigger if you can manage it. You'll sleep better and avoid dragging onto lee shore, or worse, other boats. Sounds like windage is greatly reduced if you can keep her pointed true to wind as Mark suggests with proper gear. I have had CQR's on my boats, I just haven't had the money to get one of the modern anchors -AND- the CQR has been solid for hundreds of nights, in wind, currents, etc. I just sailed up to Annapolis and back and the Bruce has an advantage over a plow in some areas, I think.

Lots of opinions on anchors. Carry lots, upsize your plow type as primary for general re-setting, keep the Fortess handy as a second for a blow, and perhaps to double as a stern anchor as an e-brake or for bahamian moor.

Sounds like you've avoided dragging so far, enjoy your cruise! Not sure I added anything new here but clearly I'm moved to share my opinion.

[Exile]

Originally Posted by cheoah

There is a compromise in every anchor; I agree that Fortress is a great one to have stored away for the right times. In mud, with consistent winds from a storm event, it will likely outperform the plow types I usually deploy. Before I set a good storm mooring, I used a big fortress for hurricanes, set in tandem with a plow-type.

In the end, chafe is the equalizer.

Ronald, do you carry a Rocna, or a Delta? Either one would do, but consider getting a bigger one, minimum 25 lbs -- bigger if you can manage it. You'll sleep better and avoid dragging onto lee shore, or worse, other boats. Sounds like windage is greatly reduced if you can keep her pointed true to wind as Mark suggests with proper gear. I have had CQR's on my boats, I just haven't had the money to get one of the modern anchors -AND- the CQR has been solid for hundreds of nights, in wind, currents, etc. I just sailed up to Annapolis and back and the Bruce has an advantage over a plow in some areas, I think.

Lots of opinions on anchors. Carry lots, upsize your plow type as primary for general re-setting, keep the Fortess handy as a second for a blow, and perhaps to double as a stern anchor as an e-brake or for bahamian moor.

Sounds like you've avoided dragging so far, enjoy your cruise! Not sure I added anything new here but clearly I'm moved to share my opinion.

A bit off topic perhaps, but I wanted to ask if you wouldn't mind also sharing how you go about setting your anchors in tandem for storms, etc.? Does the Fortress go down first, followed by the plow? How do you insure both set properly given the length of chain b'twn the two?

Thanks.

[cheoah]

Originally Posted by Exile

A bit off topic perhaps, but I wanted to ask if you wouldn't mind also sharing how you go about setting your anchors in tandem for storms, etc.? Does the Fortress go down first, followed by the plow? How do you insure both set properly given the length of chain b'twn the two?

Thanks.

Hi Exile, I've never set a Fortress first that I can recall, save for a kegde . I've deployed it, or had it ready to deploy while out cruising for thunderstorms, strong fronts, or tropical storms. I always set my primary with at least 10:1 when high winds are expected, but often much more as with surge conditions, depths can increase a lot. I expect this anchor to hold the boat alone, really, and use only good ACCO chain, Crosby U.S. shackles, quality 3-strand rode and chafe protection. Hurricane Irene moved slowly last year through NC, many boats grounded. My chafe protection burned through and the cat hole started into my line -- barely.

So, I set the secondary, often a Fortress, with a dinghy, or when singlehanding and winds are already up, I motor up with the mutha ship. I motor up to a point I have taken a mental snapshot of, after thinking of where that point needs to be, to attain proper scope. You either get that right or you know it was too close, if your rode is marked. It doesn't have to be the same scope as the primary, but should be set generously in case it becomes the sole anchor.

All that said, I generally loathe setting 2 anchors. I do it in circumstances I think it is prudent, but if I'm on board, and have good holding to myself, just one piece of gear will do up to gale force winds that may be shifting.

A little chatty there, but bottom line, I set it second, roughly 45 degrees to other anchor, and it should snug up at the proper scope. Technically, I think that tandem means two anchors in series on one rode. I wonder if that's what you're asking. Oh well, I drank coffee this morning, then did a faceplant while working cattle. Guess I missed the nuance of your post, and took some liberties with anchoring lexicon....

[Exile]

Originally Posted by cheoah

Hi Exile, I've never set a Fortress first that I can recall, save for a kegde . I've deployed it, or had it ready to deploy while out cruising for thunderstorms, strong fronts, or tropical storms. I always set my primary with at least 10:1 when high winds are expected, but often much more as with surge conditions, depths can increase a lot. I expect this anchor to hold the boat alone, really, and use only good ACCO chain, Crosby U.S. shackles, quality 3-strand rode and chafe protection. Hurricane Irene moved slowly last year through NC, many boats grounded. My chafe protection burned through and the cat hole started into my line -- barely.

So, I set the secondary, often a Fortress, with a dinghy, or when singlehanding and winds are already up, I motor up with the mutha ship. I motor up to a point I have taken a mental snapshot of, after thinking of where that point needs to be, to attain proper scope. You either get that right or you know it was too close, if your rode is marked. It doesn't have to be the same scope as the primary, but should be set generously in case it becomes the sole anchor.

All that said, I generally loathe setting 2 anchors. I do it in circumstances I think it is prudent, but if I'm on board, and have good holding to myself, just one piece of gear will do up to gale force winds that may be shifting.

A little chatty there, but bottom line, I set it second, roughly 45 degrees to other anchor, and it should snug up at the proper scope. Technically, I think that tandem means two anchors in series on one rode. I wonder if that's what you're asking. Oh well, I drank coffee this morning, then did a faceplant while working cattle. Guess I missed the nuance of your post, and took some liberties with anchoring lexicon....

Your approach MUST be exactly correct, since it is exactly MY approach when (rarely, if ever) setting two anchors separately! As you suspected, I was actually wondering about setting two anchors along one rode, with the first anchor attached by chain to the head of the second anchor. I suppose the first serves to secure the second, so a Fortress might be the choice for that. Was just trying to visualize how to be sure both anchors would properly set, but it's been written about elsewhere and not really on topic. All good info, btw -- thanks!