An anchor, when it holds, can provide a boater the greatest peace of mind, or bring the most exasperated frustration when it does not. One of the most challenging places to anchor is in the thick mud of the Chesapeake Bay. The consistency of the bottom ranges from a soupy grey sludge mixed with sand and oyster shells to a thick clay that can be molded into pottery. What anchor holds best in mud? Fortress Marine Anchors took the lead in conducting an independent study of twelve of today’s popular anchors. For four days in August, off the shores of Solomons Island, Md., I watched as anchors were lowered and retrieved in hopes of answering this question once and for all.
The test was conducted aboard the Rachel Carson, an 81 foot research vessel owned by the University of Maryland Center for Environmental Science. The ability to stabilize the vessel within fractions of a meter using the Dynamic Positioning System (DPS) played a huge role in the test’s protocol.
Each anchor was dropped at a specific location within a test zone. The initial payout was 5:1 scope with an additional 100 feet added to about 8:1 to begin the test. Once ready, the Rachel Carson enabled the DPS to stabilize its position. The anchors were then mechanically winched at a rate of 10 feet per minute over the course of 100 feet. A special tensiometer measured the torque on the line throughout the duration of each test. Once the test was complete, the Rachel Carson returned to the original drop location for the next test, altering its position slightly to pull the anchor in a fresh direction. All twelve anchors were tested in five zones. Chuck Hawley, a marine industry consultant and former Vice President of Product Test at West Marine, was the independent observer for the test.
Fortress went above and beyond requirements to establish a protocol that leveled the playing field for all anchors, but it was not without problems. The first throw of the day, the Lewmar Claw had great holding tension before breaking free after five minutes. Visual observations showed a slack rode, however the computers registered negative readings. Testing was halted to recalibrate the tensiometer before continuing.
Other variables also came into play. The wake of a passing work boat created elevated torque as it rocked the Rachel Carson. The DPS also played a role in the fluctuation while stabilizing the vessel. Even one location over another was favorable for some anchors. As Mr. Hawley observed, “In general, not surprisingly, where you anchor is really important, as well as what kind of anchor you use.” Each anchor had moments of triumph and less than stellar performances throughout four test cycles.
A great concern for all involved in the testing was that the anchors were not given a chance to set properly. “We haven’t been following our own recommendations for setting a Fortress anchor in mud,” said Brian Sheehan of Fortress Anchors in Fort Lauderdale. After great debate and careful consideration to all anchors in the test, Hawley agreed to a change in the protocol in round five. The anchors were launched with an initial scope of 2:1 then pulled in 20 feet at 30 feet per minute until a load of 200-300 lbs. of torque indicated the anchor was set. From there the 8:1 scope was let out and the test resumed as normal. First up was the Fortress FX-37 at 45 degrees.
From the moment the computer began to display the tension, everyone on board knew we were in for high readings. The tension steadily climbed to over 2000 lbs. before breaking free at the nine-minute mark. True to Fortress’ fluke style design the anchor quickly reset and immediately began climbing the chart again. At ten minutes, the test was over and it was time to retrieve the anchor. As we all began to talk about the amazing results, an aura of urgency could be felt from the Chief Engineer and Chuck Hawley. The computer screen was still active so I could see the tension was continuing to climb. It was clear that the Fortress had buried itself deep into the Chesapeake mud and it would take extra attention to retrieve. In a blink of an eye, the wire rode snapped, rocking the A-frame on the aft deck. The frayed wire rode lay on the deck of the Rachel Carson with no anchor to be found. From all calculations, the Fortress F-37 was buried 13 feet in the mud – a testament that when set properly for the conditions the Fortress digs in and stays.
Not every anchor fared as well using this new protocol. The Delta, Rocna and Spade didn’t show signs of setting while the Boss, Ultra and Danforth HT initially set before breaking out, and never recovered. It is worth noting that, due to time, only one round was completed using this protocol.
So what anchor is the best in mud? I’m not really sure we answered that question during those four days. The Danforth style anchors involved, on average, had greater tension readings than many of the plow style anchors, however all anchors involved had their moments of glory. As Cap’n Fatty Goodlander wrote in Anchoring a Boat, The Ultimate Guide in the June issue of All At Sea, “Different anchors do different things well.” Use this test as part of your research to find the best anchor(s) for you.
All plow-style anchors were in the 44 – 46 lb. range. The weights of the Danforth-style anchors are noted.
Lewmar Claw – When the Claw set, the results showed a steady, consistent rise in tension, however twice the Claw released and didn’t reset.
Manson Boss – During all five tests the Boss set easily and steadily climbed in tension. However, in three of the five tests, the anchor released after five minutes and never reset.
Ultra Supreme – Very consistent throughout all tests. Only once did the anchor release and never reset. Maximum test readings peaked in the 900 – 1100 lb. range. Solid performance.
Danforth HT (35 lb.) – This pivoting fluke-style anchor handled the mud very well, digging in quickly and steadily climbed in tension. Twice the tension dramatically dropped from its max high but regained holding, and began setting again.
Fortress FX-37 at 45° fluke position (21 lbs.) – There was no stopping the performance of the Fortress once it set into the mud. Twice though, it struggled to set, not digging in until the last minute or two of the test. It demonstrated three maximum readings in the 2000-lb. range.
Mantus – Steadily climbed in tension, reaching max performance within an average of four minutes then maintained tension throughout the duration of the test. A solid 500-lb. performer.
Lewmar CQR – This popular anchor appeared to struggle with the mud, only once climbing to a max tension of 800 lbs. All other tests were consistent in tension throughout, averaging 300 lbs.
Fortress FX-37 at 32° fluke position (21 lbs.) – With a fluke setting recommended for sand, this anchor handled the mud well. Only once did it fail to set. Once dug in the anchor maintained tension throughout test.
Lewmar Delta – Twice the Delta showed signs of handling the mud, reaching max tension of 700 lbs. Three of the five tests had very low tension readings indicating the anchor didn’t set.
Rocna – Only one test showed the potential for this popular anchor. The other four tests were flat, indicating the anchor never set.
Manson Supreme – Solid performance throughout all five tests maxing out at around 900 lbs. The anchor did, however, release three times at the seven to nine minute mark and did not reset.
Spade – Four of the five tests the anchor set early then maintained whatever tension it had until the last three minutes when holding tension increased. Only once did the Spade appear not to set.
HERE IS THE OFFICIAL REPORT: Chesapeake Bay Anchor Test 2014