In sand: Plow or Fortress?

[lsearite]

I'm having to leave a mooning ball and anchor in a busy harbor for a couple of nights. There will be some gusting winds around 24 mph and it is a sandy bottom. Harbor master advised to use the fortress. I would like to hear others experience.

Sent from my SM-N900V using Cruisers Sailing Forum mobile app

[Steadman Uhlich]

Here is an outstanding video you should watch. Actually every sailor should watch it. It was created by CF member PANOPE. He did an excellent job of testing and producing the videos too.

In this video, which is #56 in his series of anchor testing videos, he has put together a compilation that shows the highlights from many other videos, along with summary statements based on his tests.

Of course you can also view his other videos, where each anchor is featured in several tests. Since you are concerned about two anchors you have, watch the videos for each of those too, where you can see for yourself what happens underwater.

For example, the Fortress anchor is featured in several videos, each with a different scope. Simply go to Panope's channel on YouTube and look down the list of videos to find the anchor you want to watch, but make sure you look over the list because there are several videos for each anchor type, and they are not in alphabetical order.

I encourage everyone to watch the videos, and subscribe to the PANOPE YouTube channel, and leave a comment there too to help Steve (PANOPE). Let's help him as he has helped us.

PANOPE Anchor Test Compilation

https://youtu.be/l59f-OjWoq0

In this video the Fortress anchor is shown tested at about 18:00 minutes into the video.

NOTE! These tests were done at various scopes. Part of the testing protocol was to try the anchors at decreasing scope, to find what the shortest scope would be for holding. At the point in the video above, the scope was ONLY 2.5 (short scope!) in sandy mud.

[barnakiel]

If the sand is good, anything danfoth style is good. If the sand is lose or shallow, it is not.

The harbour master is supposed to know. Should anything go wrong, the problem is yours, not theirs.

Plow (cqr style) I gave up on them some 15 years ago. I believe they are decent in English mud.

b.

[Cheechako]

Depends on the plow. For those winds either will work. The Danforth/Fortress has way more holding power though. The only trouble is when the wind shifts significantly, then anchors pull out and often don't reset.
All bets are off if it's hardpan under shallow sand.

[noelex 77]

Neither is ideal. By plow anchor, I assume you mean a CQR copy, which is one of the poorer anchor designs.

The Fortress has great holding in soft sand, but in my opinion is not enormously reliable if the direction of pull changes.

It does not take much to hold a boat in 24 mph winds, what size are these anchors?

I would be tempted to use the Fortress and keep a watch if there is change in the direction of pull. You can set an anchor alarm to wake you if the wind (or current) direction changes.

[thinwater]

Originally Posted by noelex 77

Neither is ideal. By plow anchor, I assume you mean a CQR copy, which is one of the poorer anchor designs.

The Fortress has great holding in soft sand, but in my opinion is not enormously reliable if the direction of pull changes.

It does not take much to hold a boat in 24 mph winds, what size are these anchors?

I would be tempted to use the Fortress and keep a very careful watch if there is change in the direction of pull. You can set an anchor alarm to wake you if the wind (or current) direction changes.

What he said. I would add that a Fortress depends on a deep power set to handle direction changes. As a general rule, it will hold about as much force in a sift as it was set with. That will also be about the force required to retrieve.

So if you are going to use a Fortress, set it in the direction of greatest expected wind, and back down hard for a few minutes.

[noelex 77]

Originally Posted by thinwater

So if you are going to use a Fortress, set it in the direction of greatest expected wind, and back down hard for a few minutes.

Thanks Thinwater.

I have experimented with setting anchors in the direction of the forecast wind rather than the prevailing wind.

This is obviously of no use if the prevailing wind is strong or even moderate. The anchor will simply rotate around to the prevailing wind and nothing is gained. However, if the prevailing wind is light and will stay light until a forecast wind from another direction arrives then the anchor if set in the direction of the forcast wind direction will stay in the correct orientation for the new wind.

This technique has particular application to anchors that don't rotate reliably.

To cut a long story short, the technique did not work well for me. The main problem was that when trying to set the anchor crosswind or downwind the prevailing wind and any prop walk would cause the setting direction to change. Anchors like to set in a consistent direction. Most modern designs can rotate very reliably when set, but they dislike a change in direction while digging in.

In the end I gave up on the technique. Underwater observation showed the set was worse.

However, I have often wondered if a cat (or perhaps even a monohull with bow thruster) could keep the direction of pull constant enough in a crosswind to make the technique work. The rudder is of no use because there is no water flow if you are stationary, which of course you will be if the anchor is holding.

It might, in my view, be especially useful for Danforth/Fortress anchors if the direction of pull could beheld constant.

Have you tried this technique?

[Hydra]

Maybe it would be possible to set an anchor in a crosswind from the stern, with a bridle. In this situation, the flow from the propeller on the rudder might be sufficient to keep the boat in position. And the increased pull would set the anchor deeper.

Alain

[noelex 77]

Yes I think that would work well Alain.

In forward the flow over the rudder could be used to counteract the crosswind and as you say most boats have more thrust in forward, so the set would be potentially deeper.

Has anyone given this a try?

[lsearite]

Thanks to all. What good information! !

Sent from my SM-N900V using Cruisers Sailing Forum mobile app

[El Pinguino]

I would opt for the Fortress ( or any others of that style ) or a fisherman type on sand, especially hard sand.
As stated above... the CQR is a mud anchor.

[Panope]

Originally Posted by Hydra

Maybe it would be possible to set an anchor in a crosswind from the stern, with a bridle. In this situation, the flow from the propeller on the rudder might be sufficient to keep the boat in position. And the increased pull would set the anchor deeper.

Alain

Originally Posted by noelex 77

Yes I think that would work well Alain.

In forward the flow over the rudder could be used to counteract the crosswind and as you say most boats have more thrust in forward, so the set would be potentially deeper.

Has anyone given this a try?

I did a number of "from the stern" pulls with a bridal in my anchor testing. Just for kicks, I tried to 'maneuver' or 'aim' the boat with the rudder during the pulls: It was as if the rudder had fallen off. Nothing. Nada.

Perhaps if a bridal is NOT used, and the attach bollard could somehow be positioned near or even forward of the rudder (like a tugboat), the boat could be maneuvered as hoped.

Steve

[noelex 77]

Thanks Steve

It is interesting that the rudder did not not give more control in forward with the effect of the prop wash.

I think the first priority is to set the anchor in straight line even if the anchor rotates poorly. I think this is preferable to subjecting the anchor to a changing direction of pull while it is trying to set.

[thinwater]

Originally Posted by noelex 77

Thanks Thinwater.

I have experimented with setting anchors in the direction of the forecast wind rather than the prevailing wind.

This is obviously of no use if the prevailing wind is strong or even moderate. The anchor will simply rotate around to the prevailing wind and nothing is gained. However, if the prevailing wind is light and will stay light until a forecast wind from another direction arrives then the anchor if set in the direction of the forcast wind direction will stay in the correct orientation for the new wind.

This technique has particular application to anchors that don't rotate reliably.

To cut a long story short, the technique did not work well for me. The main problem was that when trying to set the anchor crosswind or downwind the prevailing wind and any prop walk would cause the setting direction to change. Anchors like to set in a consistent direction. Most modern designs can rotate very reliably when set, but they dislike a change in direction while digging in.

In the end I gave up on the technique. Underwater observation showed the set was worse.

However, I have often wondered if a cat (or perhaps even a monohull with bow thruster) could keep the direction of pull constant enough in a crosswind to make the technique work. The rudder is of no use because there is no water flow if you are stationary, which of course you will be if the anchor is holding.

It might, in my view, be especially useful for Danforth/Fortress anchors if the direction of pull could beheld constant.

Have you tried this technique?

Yes (set in direction of anticipated wind), but different. In soft mud (common here) the anchor will set so deeply (many feet underground) that rotation is impossible. This depends on the size of the anchor and the density of the bottom. If you use a conservatively sized Fortress on hard sand, it does not set deeply and is very vulnerable to shifts. Curiously, if you use a smaller Fortress, it will go very deep and stay put. It can be a real bugger to get out, much harder than "modern" anchors. I've had a 2# guardian require 450 pounds of verticl pull (measured) to recover. It was DEEP.

This is that one case where sometimes a smaller anchor can be as secure, at least up to mild storm strength. Very strange. However, it may not apply to the OPs sand question, and does not conflict with your sand experience, which I agree with. It's a mud thing and a smaller anchor thing.

The interesting thing about this is that unlike every other anchor design, it makes me wonder if most of the time, Fortress anchors should NOT be oversized for best performance. You want them deep to handle shifts. Of course, recovery becomes painful. A cable rode makes the difference even more obvious (more hold, deeper set, harder to retrieve).

[Snowpetrel]

Interesting question. In the name of anchor science you could test both for us. See what holds best!

Id be interested to hear Panopes take on this, but if I recall correctly from his videos the fortress reset ok in sand during an earlier reversal test, but it struggled in the sticky stuff when the flukes got jammed up by the mud. I am speculating, but in clean sand with a reversal hopefully the flukes will clear and the anchor should reset easily enough as long as the boat isn't moving too fast?

A lot depends on the exact nature of the bottom, but the fortress should out hold the CQR by a large margin on that bottom.

If it gets bad, or you are worried set both on separate rodes. Make sure you can untie the bitter end of one rode and untwist them easily from on deck!