In 30 years of cruising, we have had two complete rode failures on our boats, both occurring in light to moderate weather when such an event was the farthest thing from our minds. In the first case, a highly-polished stainless steel double-jaw swivel (read "expensive") simply broke in half. It was less than six months old and showed no signs of crevice corrosion. When we hauled up the chain, one half of the swivel was still wired to the end with a nice, round hole where the swivel pin had previously resided. We never found the anchor, the pin, or the other half of the swivel on the soft mud bottom.
Beyond these two inexplicable events, we've had several cases of anchors pulling out after as much as 12 days in the same spot. Usually, this comes with a fast wind switch or change of tidal current flow. Often, such a breakout is assisted by anomalies on the bottom, and we have pulled up tires, gallon paint pails, and once a six-foot length of picket fence on the tips of our anchors.
It is little wonder then that we feel more secure when we have two anchors down. It is simply the best insurance policy that can be bought with a little extra work. This is not to say that we always use two hooks.
In fact, it isn't terribly uncommon for us to set three anchors, or even four, especially when cruising Florida and the Bahamas in the winter. Cold fronts sweeping as far south as the Virgin Islands from December to April can pack nasty squalls with hurricane force gusts in their forward roll clouds, often accompanied by a wind shift of over 90 degrees. A nice, tight anchorage is the place to weather these fronts, but only if you can keep the keel off the beach by setting three or four hooks into terra firma.
The most typical uses of a two-anchor system off the bow is to place the two rodes anywhere from directly in line to a V formation of about 45 degrees. It is important to recognize that the width of the V, or the distance between the anchors in relationship to the scope, has a profound effect on how the boat behaves. If you play with the concept on a piece of paper, you will shortly see that the wider the V, the more the boat is limited from swinging either to port or starboard. In fact, there are several ways in which two anchors are set 180 degrees apart that are used specifically to limit swing to near zero in a crowded mooring field or a narrow stream. We will cover the techniques of the Bahamian moor and fore-and-aft anchoring in a future article.
After such a wind switch has left you with the anchors out ahead, one rode will be completely slack (in this case it will be the port one). This gives rise to several choices. You can let out additional rode on the starboard anchor if you wish to continue sitting with equal tension on both hooks. Or you can leave the boat as it is, tied to the bottom with only the starboard anchor, leaving the port rode slack as a safety. This latter technique limits your swinging radius port and starboard. After all, one of the key reasons to use two anchors in the first place is to limit the swinging radius of the boat to the sides.
But let's reverse the thinking process. If the north wind is going to clock to the east, this new east wind would leave you a north/south baseline for your anchors. If you put the two hooks straight out ahead of the boat along this north/south line in the first place, the port one directly in front of the starboard, the boat will swing just like all the other boats around her that are anchored on just one hook in the present north wind. But as the wind switches, the longer rode on the port (forward) anchor will go slack, and the boat will be sitting on only the shorter, starboard rode. At this point, all you need do is to saunter forward and pull in the slack port anchor rode, and you will neatly be anchored on a V formation, ready to weather the stronger breezes. Where a wind shift is expected, this technique can keep you from performing a firedrill in the dinghy after the wind changes and builds—you can relax and watch all the other cruisers perform these antics.
Using two anchors pays big dividends in how well you sleep at night and how hard you must work during changes in wind direction. With a little forethought and practice, you may find that you're the most relaxed crew in the anchorage.
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