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SOFT MUD BOTTOM ANCHOR TEST On June 26, 2003 off Gulfport, Mississippi a number of popular boating anchors were tested in a soft mud sea bottom. Most anchors work well in sand and hard mud bottom conditions. Real mud bottoms, however, stretch across vast areas of coastline in the United States, so it is important to determine which anchors do well in these bottoms. Most boaters are forced to anchor in the few bays and inlets that have hard or sand bottoms because their anchors only hold well in these places, whereas if they had proper anchoring equipment for mud bottoms, they could safely anchor in more secluded places. If they have anchors that work well in all of the bottom types, then they are truly equipped to cruise happily and safely wherever they want to go. No official mud bottom tests have been made in recent years and there have been many new anchor types that have become available. This test is deemed to be very important to boaters of all types, since the information gained will be so very useful for boat operators. Tests previously made by Practical Sailor and Powerboat Reports in purported mud were admitted to have been in 18 inches of soup over gravel. This turned out to be a gravel test. The PS/PBR tests have all been flawed in that the anchors tested were always set and pulled with the rode leading ashore where it was attached to a dynamometer. The scopes as a result were equivalent to 100 to I since the rodes were laying on the bottom. The Bruce, CQR, Delta and Danforth types had not been designed as penetrating anchors. Their purpose is to penetrate the bottom on more than two feet. The rodes laying on the bottom favor this type of anchors, and thus the PS/PBR tests showed these anchors to good advantage. Boaters however seldom extend their anchor rode's scopes to as much as 7 to 1, let alone 100 to 1. More likely it is 5 to t or less. The Max and Super Max anchors were designed to set and penetrate deeper and deeper as more strain is applied. When they are set with a 100 to I scope as in the cases of the PS/PBR tests, they will not perform as they were designed to do. That is why the ABS tests from an actual tugboat showed the true characteristics and capabilities of the anchors tested. The scopes of 6 to I were used for anchors whose manufacturers recommended 7 to 1, since it was the medium between what boaters normally would use, 5 to 1. This
anchor test is certified by the American Bureau of
Shipping, the most trusted maritime authority in the
United States. |
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| Scopes were applied as per the
manufacturers’ recommendations as well as their
recommendations regarding chain or bare nylon anchor
rode. A tugboat was used as the test vehicle. The
“Commodore” is one of the Gulfport Towing
Company’s fleet, and it has a 1200 horsepower
Fairbanks-Morse diesel engine and a 72 inch propeller. A
Dillon dynamometer was used to measure the pull pressures
on the rodes. Anchors were dropped and straight pulls were measured. It was deemed unnecessary to do 90 degree offset pulls as the soft bottom would allow each anchor to turn to the new position effortlessly. Anchors were dropped from the stern of the Commodore along with their rodes. The boat’s momentum from the wind was allowed to set each anchor. Since the wind varied, differing setting pressures were seen. Then after setting, force from the engine was applied to determine the point when dragging occurred. Due to the time required and the large number of anchors to be tested, only one test per anchor was made. |
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The results were as follows: 16.5 pound aluminum SPADE anchor with a 6-1 scope with chain did not set and had a maximum pressure on the rode of 130 pounds. 17 pound XYZ prototype steel anchor with a 5-1 scope with all-nylon rode set with 200 pounds pressure and dragged at 400 pounds. 17 pound steel alloy DIGGER anchor with a 5-1 scope and all-nylon rode did not set and had no measurable pressure on the rode while dragging. 21 pound aluminum FORTRESS FX37 anchor with a 6-1 scope and chain did not set and had no measurable pressure on the rode while dragging. 26 pound WEST MARINE Danforth steel anchor with a 6-1 scope and chain did not set and had a maximum of 200 pounds pressure on the rode while dragging. 29.5 pound steel BARNACLE anchor with a 6-1 scope and with chain had no set and no measurable pressure on the rode while dragging. 29.5 pound steel BULLWAGGA anchor with a 5-1 scope and all-nylon rode had a set at 300 pounds pressure on the rode, and was dragging at 390 pounds pressure. 35 pound aluminum DELTA anchor with a scope of 6-1 and with chain had a set of 400 pounds pressure and dragged thereafter. A maximum pull pressure while dragging was experienced of 900 pounds momentarily which was thought to be due to an underbottom obstruction. 48 pound steel CQR anchor with a 6-1 scope with chain never set but dragged with a maximum pressure of 575 pounds on the rode. 46.5 pound steel BRUCE anchor with a 6-1 scope and chain never set but had a maximum pressure of 400 pounds while dragging. 52 pound steel SUPER MAX 17 Pivoting Arm anchor with a 5-1 scope and all-nylon rode set at 570 pounds and began dragging at 700 pounds pressure on the rode.
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| In the above tests if the anchor did not set by bringing the tugboat to a complete stop and holding there, then a maximum pull pressure was obtained while the boat was drifting. These pressures were logged at the maximum, whereas in fact the pressures were varying normally at much lower levels. Maximums could have been influenced by underbottom obstructions or more solid or harder mud conditions temporarily met. | The conclusion reached from this test was that only four anchors provided a set in this bottom, the XYZ prototype anchor, the Bullwagga, the Delta and the Super Max anchor. Of the four, only the Super Max anchor provided security up to 700 pounds of pull, while the others dragged from 390 and 400 pounds on. The XYZ and the Super Max anchors are deep penetration anchors by design, and it is felt that with time and constant pressure both types would penetrate deeper and thus create added holding pressures. Since the Super Max anchor has an adjustable arm that can be changed for differing types of bottom conditions, it appears to be the best anchor for all-around anchoring usage, since it has been proven in others’ tests in sand, gravel and coral bottoms. The XYZ in order to be competitive with the Super Max anchor in soft mud bottoms would need to be quite a bit heavier and larger in fluke area. | ||||||||||
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