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Anchoring Control

7K views 0 replies 1 participant last post by  Liza Copeland 
#1 ·

The noise of the engine, wind, and other obstructions like dodgers can all hamper communications during anchoring. Using hand signals between the person on the bow and the helmsman makes intent clear, and won't disturb neighboring boats.
Anchoring out is one of the greatest pleasures of cruising-the freedom of swinging on the hook, the peacefulness of the deserted anchorage, and being surrounded by the wonders of nature are what make voyaging under sail such a joy. Secure anchoring, however, is one of the most demanding maneuvers on board, and is something to read about, practice, analyze, and then practice some more.

Choose a deserted anchorage to work out your routines, as the unexpected is always lurking closeby in a crowded one, especially one filled with friends! Develop a set of hand signals-such as forward, back, stop, slow down, faster, to port, to starboard, finished-as nothing is more demoralizing than a shouted exchange between the person on the bow and the person at the helm, with the volume at an ever-escalating pitch. Hand signals that are distinctive work well, eradicating the need for most verbal exchange. Also significant is a mutual understanding that the perspectives from the bow and stern can be very different. A good way to reinforce this is to change places regularly.

Study the chart and assess the anchorage to find a desirable spot for the boat to lie. The bottom characteristics, tidal range and current, depth, wind strength and obstructions such as reefs or other vessels must all be considered. In the tropics look for white sand and avoid anchoring in coral. The common anchoring practice is to motor or sail upwind, checking the depth to estimate the scope required. The anchor is dropped just as you begin to back down. Go astern slowly applying enough tension on the rode to dig the anchor in with the chain lying straight, but not so much that the anchor breaks out because it has been jerked away before properly buried.

When using the engine to back down, the 'paddle wheel' effect of the propeller will initially make the stern swing one way. Our stern kicks to port so we turn the bow to port (i.e. the stern turns to starboard) to compensate just before going astern. On modern designs you can also straighten up with a quick burst on the throttle. Tension on the rode will naturally align the boat.


When picking a place between vessels in an anchorage, anchor near boats that have similar sizes and underbodies. Changing tides and winds can have some vessels swinging faster than others, and if anchoring scopes overlap, there is the possibility of contact.
The desired scope is dependent on anchor and rode type, as well as depth, swinging room, the weather, current and state of the tide. Ideal safe scope using rope and chain is generally considered to be 7:1. Slightly less can be used with all chain in shallow water, but never less than 4:1 for all chain in depths over 35'. After the rode is secured, the anchor should be dug in by using increased revs on the engine. If the rode stays taut without the boat moving against a fixed point on shore then the anchor is set. If practical, dive to see how the anchor is lying. Then relax, keeping an eye on your position in relation to the shore and other boats, particularly if the conditions are changing.

Long-distance cruising calls for more anchoring than anticipated, depending on the area and your budget. We anchored about 80 percent of the time during our six-year circumnavigation and judge ourselves typical cruisers. In some places there were marinas, but because they were expensive we generally only went in once a week to do laundry, fill the water tanks, shower, and allow our children a free rein. Sometimes we went stern-to a wharf, but most of the time anchoring was the only option.


If the weather is expected to turn against you, a second anchor can be used for increased security and peace of mind.
Configurations of two anchors can be used for increased security in bad weather, to hold the boat into a swell, prevent rolling when the wind is at right angles to the current, or in anchorages where there is a strong reversing tidal current. For example we use two anchors set at 45 degrees from the bow when we expect strong winds, or have limited swinging room. The Bahamian moor, where one anchor is set upstream and one downstream from the bow, works well in areas where there are strong reversing currents. We find the combination of our 22-pound Danforth in series with the 33-pound Bruce shackled to the crown with 20-feet of chain, gives tremendous holding power. It is easier to recover than two anchors streamed separately from the bow and avoids the problem of the rodes twisting together as the boat swings with the tide. In some areas, particularly in the Mediterranean (hence the term Med-moor), or in small, windless anchorages such as we have in abundance in the Pacific Northwest, anchoring from the bow (or stern) with lines ashore is common. Many boats can anchor safely together this way in small anchorages.

If more than one anchor is set, consider the other boats in the vicinity carefully. Many a time we've seen havoc created in a crowded anchorage when the tide or wind changes and all the boats swing but one. A similar result can occur with different rode lengths.

Despite vast experience, everyone who anchors frequently has some anchoring stories. Our first disaster was in Cascais, on the Portuguese Atlantic coast. All was peaceful when we retired, a light wind blowing Bagheera gently offshore, but during the night the wind changed, both in strength and direction. We awoke to find we were on a lee shore with short steep waves building. It was time to leave, but try as we might, the anchor would not come free. We circled around hoping to break it out, and peered into the murky water to try to figure out the problem. Suddenly a huge breaking wave thrust Bagheera's bow high in the air. The chain tightened with a jerk, ripping the windlass from the deck with an ugly screech. There was only one option left if we wanted to keep the anchor. In extremely rough conditions Andy dove to the bottom. He found that we had snagged on a huge ship's anchor chain, which probably had lain untouched for more than a century.


Vigilance is required in tight anchoring quarters, as the author found out. A neighboring vessel can retrieve the anchor, and drag its hook over yours, leaving your anchor with little holding power.
We felt jinxed in Madeira-our second incident happened on Halloween! The anchor had been bedded in for a week outside the harbor at Funchal, and the inner harbor was very crowded. We were touring the beautiful island when a cruiser dropped his anchor over ours, changed his mind, lifted ours with his, then casually tossed ours back, our neighbors reported. When a squall came through Bagheera dragged, pounded on the rocks and smashed the bottom third of the rudder. It took ten days of rebuilding, fiberglassing and sanding to repair the damage.

By comparison, the Kenyan episode was a peaceful event. We were north of Mombassa, the children had just returned from a trip to a safari park, and we were running late. As soon as they were on board, we powered full speed to the other side of the inlet to meet friends at a local event. We had been to the anchorage several times, so we were familiar with the long drop off. At dusk, Andy dropped the anchor and large quantities of chain close to two other boats. We leapt into the dinghy and rushed ashore to be in time for our date. As we returned to the beach after dinner, Jamie, our youngest son, ran ahead. Suddenly he called out, "There's a boat on its side." It took us only two seconds to deduce which one!

We slept that night at a crazy angle of heel, and by 10:00 a.m. we had happily returned to our upright state. As we had coffee, we soon came to the conclusion that we hadn't dragged at all-there had just been so much chain out that we drifted ashore.
 
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