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Discussion Starter · #1 ·
Hello Sailors,

Just a quick note to let you know that during the week of August 4th, we will be conducting an anchor holding power test in the soft mud bottoms of the Chesapeake Bay aboard the 81-ft Rachel Carson, a research vessel that is owned & operated by the University of Maryland Center for Environmental Science in Solomons, MD.

Chuck Hawley, who is a long-time sailor with an impressive resume will be aboard to serve as an independent reviewer of the testing. Chuck was formerly the VP of Product Testing at West Marine for many years, and he was present at the tests we conducted in the SF Bay way back in 1990, and he was also involved in West Marine's highly-publicized tests that were conducted in 2006.

We will also have aboard a solid group from the boating media as well, with writers from several of the USA's largest magazines.

I will keep you updated on the progress of the testing once we begin, which I am sure will be of great interest to many of you.

Have a great weekend,
Brian Sheehan

Fortress Marine Anchors
 

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Don't get me wrong, I love Fortress, have had one on every boat, but I don't see what this will tell us. We already know that Fortress is extremely powerful for its weight in consistent bottoms. But...

--Leaves in Dividing Creek
--Soup in Harness Creek
--Thin sand over rock-hard clay along the cliffs
--Oyster shell a few places
--Weeds a few places

Perhaps the data that would be most useful relates to wind shifts. If set hard (X) in one direction, how much strain (%X) will it hold at 90 degrees and at 180 degrees? Does time matter (is it slowly pulling itself out--at least 8 hours)? I've had a lightly set danforth clone pull in a wind shift. I've had a well-set Fortress hold in a strong 180 degree tide shift (I had lost my primary anchor days before), but it did come out rather easily. Also, how much 90degree stress before bending (since the anchor does not shift with the load when well set, this is a question. Or can it shift in mud? Tough to photo in the Bay, but not impossible and very valuable.

I think the market already accepts the Fortress as the preferred kedge. It is shifts and tricky bottoms that bother us.
 

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Why don't you pick a test vessel closer in size and displacement to that most of us sail?
Horsepower. Not to many of us can generate 5-10,000 pounds of static pull needed to generate real storm and wave forces. Maybe 1000. Maybe.
 

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Chuckles they aren't going to go out and see if it holds the boat on any given day, they are going to intentionally break it free with the engines to see at what point it breaks free. Few of us have boats with enough static thrust to to any testing.
 

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I don't think the Rachel Carson will fit in either Dividing Creek (the one on Wye Island) or Harness Creek.
According to her specs (Rachel Carson Specifications and Equipment | The University of Maryland Center for Environmental Science) she only draws a couple of inches more than my Sabre 28. So I think we can get her into Harness Creek but it might be a little tight maneuvering. Luckily it has 2,392 more horsepower so I am sure they can make room if needed.
 

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So I think we can get her into Harness Creek but it might be a little tight maneuvering.
That was my point - 81' long and 18' wide - I'm not sure they could get around the shoal at before Quiet Waters without putting the bow on the beach. Dividing Creek gets pretty narrow and the might not be able to turn around even with their bow thruster.

Regardless it will be interesting to know where they do plan on testing.
 

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Discussion Starter · #11 ·
Thanks everyone for your input. The testing location is near where the Rachel Carson is docked in Solomons at approximately Lat: 38°18'58.49"N and Long: 76°26'48.94"W

We will not be pulling with the research vessel: it is too big, the bottoms are too soft, and the anchors are too small to be able to get consistent results.

We will be using the aft winch to do the pulling, and we have rented a running line tensiometer that will be installed on the wire rope and is capable of measuring & logging the payout, tension, and pull speed.

The research vessel will be held in place during the pulling by its "state of the art" Dynamic Positioning System.

Brian
 

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Not only is dynamic loading important to replicate, but changes in directional pull under storm force conditions after setting the anchor under the much lesser pull that replicates a sailboat motor. I think there is probably enough engineering talent on this board that could write a spec for such a test and hopefully we'll see some results that deviates from the typical "anchor tests".
 

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There's no doubt in my mind that a Fortress anchor will hold well in 90% of the Chesapeake, and offers some of the best weight to holding power ratios available.

Unfortunately, I have about as much faith in their resetting characteristics as I do the Danforth, which is to say, precious little.

If I owned a Fortress, I'd certainly keep it but I still would also own a next-generation anchor for its quick resetting characteristics for when the wind or tide changes.
 

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Discussion Starter · #16 ·
We hope to conduct windshift testing, but we have to first establish whether the anchors can handle much of a straight line pull in these soft mud bottoms, which is when they should perform at their best.

If they are not able to handle a minimal amount of load during a straight line pull, then there is obviously no reason to expect that they will perform better when they are side loaded.

Regarding the Fortress performance during wind or tidal shifts, it all depends on how well the anchor is buried beforehand, and many sailboats simply do not have the engine power to properly bury a Fortress with its two massive, precision-machined and sharpened flukes.

But if the Fortress is well buried with the help of some strong winds, then it will head straight to China and the issue afterwards can be getting the anchor back out.

Thanks,
Brian
 

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I agree with you Brian that once the anchor gets set deeply then it should hold under various conditions. However.....there have been occasions when I back down on the anchor using my motor and then go to sleep. During that night a wind shift occurs which can put a lot more force in a different direction on the anchor than what was used in setting it. It is under that condition that is my concern.

On a side note, I've switched from my 35 cpr to a 45 manson supreme knowing that the holding power of the manson will be better in soft mud. But from experience that little 35 pounder held my 25000 lb displacement sailboat in a cat 1 hurricane with me being aboard. I think the hinge design of the cpr is a lot more benefical to wind shifts that most people are willing to admit dispite the drawback of the plow shape. Good Luck in your testing.
 

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Regarding the Fortress performance during wind or tidal shifts, it all depends on how well the anchor is buried beforehand, and many sailboats simply do not have the engine power to properly bury a Fortress with its two massive, precision-machined and sharpened flukes.
Thanks,
Brian
You might like to think about this statement.
The typical sailboat arrives at an anchorage after a days sail, deploys and sets the anchor using the wind and engine he has, and goes about getting dinner and the evenings activities, goes to bed and then awakens to a shifting wind/tide and an anchor that is not holding because he could not "properly bury a Fortress anchor". So, why choose the Fortress if one cannot take advantage of its two massive, precision-machined and sharpened flukes?
John
 

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Indeed. It sounds like Brian is saying that the Fortress isn't suitable for most sailboats since we lack the necessary engine power to properly set the anchor.

Yet here he is, announcing to the sailing community that there will be a test of their anchors happening soon. Shouldn't he be on a power boat forum somewhere?

No problem. My newer generation anchor sets just fine with the engine power that I currently have. I guess there's no need to look into Fortress.
 

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Discussion Starter · #20 ·
Thanks for your input. A 25 HP motor on a sailboat should be able to generate about 500 lbs of load, which is comparable to the force of 30 knots of wind against a 25 foot boat.

That load will double to 1,000 lbs with a 50 HP motor, which is comparable to the force of 30 knots of wind against a 35 foot boat.

In either case, that amount of "power-setting" load should be able to bury a properly-sized Fortress anchor in a common sand, mud or clay type of bottom.

If the motor is smaller and/or if the bottom is harder and more difficult to penetrate, then a heavy, dense plow type of anchor with a single narrow fluke is likely to perform better.

Additionally, for maximum safety, we will always encourage boaters to set two anchors if a wind or tidal shift is anticipated, as no anchor will dependably re-set itself 100% of the time.

Our late company founder, who was a lifelong and very adventurous boater, with a 1,000 mile trip up the Amazon, several Atlantic crossings, and a circumnavigation is his early 70s on his resume, put it this way: "When an anchor breaks free from a sea bottom, then it might no longer be an anchor, it might just resemble a giant ball with no sharp edges in which to re-penetrate the sea bottom."

Much appreciated,
Brian
 
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