Since each shank was different, we needed to use different attachment devices at the anchor shank. Some, like the PERF 12, used standard 5/16" anchor shackles, while the FOB Light required the use of a large stainless carabiner due to its 1" shank width.

Some anchors were adjustable in fluke angle, and were tested in all configurations, even if the angle was inappropriate for the known bottom conditions.

NOTE: We were able to pull most, but not all, anchors to our predetermined limit of 1,000 lbs. In some cases, we pulled anchors to a lesser tension, but the anchors showed no signs of dragging. It is very difficult to terminate a test at precisely 1,000 lbs. Tensions in excess of 700 lbs. should be interpreted as similar unless it is specifically noted that the anchor dragged or released. Put another way, anchors which withstood 1,000 lbs. of tension may have been capable of more tension, just as anchors that withstood 700 lbs. may have been capable of more tension.

Test Location
Site A was east of Santa Cruz Wharf and west of the mouth of the San Lorenzo River. Depths varied from 20 to 24 feet, with a very hard dark gray sand bottom. We generally used 120 feet of anchor line, measured to the water surface.

Site B was west of the wharf in an area known to surfers as Cowell's Beach. Depths varied from 16 to 19 feet, in a dark sand with very fine particulate size. The material appeared to be silt or clay particles.

Site C was inside the Santa Cruz Small Craft Harbor, on a sandbar which forms in the lee of the west jetty. The bottom is white beach sand, and was awash at low tide. This allowed us to observe the anchors under tension, although some of the observations were made with the anchors in unsaturated sand, a condition which is not found in practice.

Summary of Results on 4/24/94
Each anchor was pulled at least two times in each location. If the anchor did not set, we tried anything we could think of (more or less scope, slow or fast pulls, different chain) to get it to set.

FOB Light
The FOB Light anchor weighed approximately 14 lbs. and was constructed out of cast aluminum. It is similar to a Danforth-style anchor, with adjustable fluke angles like the Fortress brand anchors. Its manufacturer's designation was E14.

The FOB worked extremely well in Site A and B in the sand configuration. We were unable to break it free at 5:1 scope in either location at tensions up to 925 lbs. We also veered the angle of pull through approximately 90° after the anchor was firmly set, and were unable to damage the anchor or get it to drag.

When reassembled in the mud orientation, the FOB would not engage in sand.

At site C, the FOB set quickly and plowed a wide trench in the sand. In each case, however, the FOB rotated in the sand until one of the stock tips protruded, whereupon it popped out of the sand and flipped onto its back. It then re-engaged the bottom and dug it. This occurred at 760 lbs. This instability appeared to be due to the short stock length relative to normal Danforth-proportioned anchors.

The FOB would not set in the mud orientation on the beach, but dragged with its crown in the air.

Digger Anchor (4/22/94)
The Digger, a self-releasing 15 lb. anchor, which can be made to release its flukes to a 180° angle if the anchor gets trapped under a snag. It is primarily sold as an inland anchor for pontoon and fishing boats.

The Digger did not set in any location, and attained tensions of no more than 160 lbs. It tripped to its 180° setting on the first pull, which made it difficult to trust since we were never sure if it was in "tripped" mode when we pulled on it.

When tested at site C, the failure mode became obvious. The anchor fluke tips quickly engaged the sand, causing the anchor to rear up with its crown up in the air. The anchor was relatively stable, dragging at about 80 lbs. of tension, on its fluke tips and the end of its shank. Then the anchor fell over and repeated this process. Had the shank been longer, thus forcing the flukes in at a shallower angle, it is possible that the flukes would have penetrated.

New Concept Anchor
The New Concept anchor, invented by Oakland resident Chuck Ford, has two flukes arranged in an inverted V shape, and a shank made from links of chain. It weighed approximately 15 lbs. This was a modified version of an anchor which we had tested approximately two years ago. It is patented, but has yet to go into production.

The New Concept did not set in any location, either using the chain which was included, or the chain on the test rode. We recorded a maximum of 110 lbs. of tension, due to its skidding on the bottom.

At site C, the New Concept began to engage with its fluke tips, then reared up and fell over. At this point, the anchor was rotated about 135° from its intended orientation and continued to drag on the sand in this orientation. The anchor appeared unstable in sand, although it is possible that it would work in soft mud.

Hans-C Anchor
The Hans-C anchor has two flukes on opposite sides of an adjustable, pivoting shank. It can be set to one of three different fluke angles.

We were not able to develop more than about 350 lbs. of tension on the 15 lb. Hans-C anchor, and this tension was recorded while the boat was making headway of about a knot. The anchor could be felt skipping by placing a hand on the anchor line. When retrieved, the pivot point was jammed with sand, and it was not obvious that the anchor would orient itself "flukes downward" on the bottom. We cleared the sand and tried several times to get the anchor to hold. As with other tests, the scope as approximately 5:1. From the boat, it felt like the central fluke point was scraping a shallow trench in the bottom.

We also tried the anchor at its other fluke angle settings, although the difference between them was hardly noticeable.

At site C, the Hans-C engaged quickly, but did not penetrate more than 3-4 inches below the surface. Sand which was caught in its fluke opening extruded through the rear of the anchor. The anchor was stable, but did not bury deeply enough to produce substantial resistance.

A source of concern was the Hans-C angle adjustment bolt, which could easily be tightened so that the anchor shank hinge was immobilized. When finger tight, it began to squeeze the shank halves together. In general, the hinge of the shank seemed problematic since the tight clearances could cause jamming. We understand that the anchor has been modified since this version was produced, so this problem may have been rectified.

West Marine Performance 12 Anchor
The PERF 12 West Marine Performance anchor was used as a benchmark for the test. It is very similar to the original Danforth 12-H anchor, and has T shaped flukes and a normal 32° fluke angle. Its actual weight is 14 lbs.

We were not able to explain the results of the Performance 12 lb. anchor. At site A and 5:1 scope, the anchor would not register tensions of over 340 lbs. without breaking free. When we increased the scope of 7.5:1, the anchor would not engage. However, when the scope was reduced to 3:1 (70' of line in 22' of water), the anchor dug in and held to 900 lbs. of tension. After it broke free, it reset and held 500 lbs.

At site B, the Performance anchor held at 4:1 scope to 940 lbs. of tension and did not release. When fully engaged, the boat was maneuvered 90° with a slack anchor line, then load was applied in an attempt to break the anchor free or damage the anchor. It did neither, and recorded a load of 1,020 lbs. in the new direction. The shank appeared unbent by this sideways pull.

At site C, the Performance anchor engaged the sand quickly, and rapidly buried until it was not visible. It was pulled to a tension of 940 lbs. and continued to dig deeper.

We suspect that the dense sand at Site A prevented the anchor from burying, but the softer sand of Sites B and C facilitated burying.

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