By: John Gullick, CPS-ECP Manager of Special Programmes
I recently received the following question about the length of chain attached to the anchor line or rode between the anchor and the line.
I gather the old ‘rule of thumb’ for anchor rode is that the chain length should be about the length of the boat. Do you know what’s that based on? For a 27 to 30-foot sailboat, how much chain should I use? Would 50 feet of chain be better as far as swing goes? We don’t want to go all chain as it would be too much weight in the bow.
The length of chain is really based on the weight of chain that will help to keep the anchor rode close to horizontal near the anchor so that the anchor will maintain its “bite” on the bottom. For a 27 to 30-foot boat, depending on the weight of the chain, about 25 feet should do the job adequately.
If you need some additional weight, a small mushroom anchor acting as a weight or kellet about 20 feet from the main anchor should do a good job.
The following is from the Canadian Power and Sail Squadron (CPS-ECP) Boating Basics Handbook used for preparing for the test for the Pleasure Craft Operator Card (PCOC).
The anchor, and the line or chain attached to it (the “rode”), are very important pieces of equipment. An anchor can make the difference between safety and disaster.
The anchor line should always be attached to the anchor and the other end of the line (bitter end) tied to the boat. Many anchors (Danforth, Bruce, Fortress and Plow) work by hooking in the bottom. They stay hooked best if a length of chain holds the shank of the anchor on the bottom. A length of chain two or three metres long should be fitted between the anchor and the line to help accomplish this.
Danforth and Mushroom anchors are the most popular for small boats. The Mushroom anchor is often used by anglers who don’t stay long in any one location. They should always be stored where they can be easily reached and quickly released.
Selecting The Anchorage
Anchoring is not always as easy as it seems and a little practice will be a big help. Choose a well-protected area, preferably with a flat bottom. Approach slowly upwind against the current. Check that the bitter end is indeed tied to the boat.
When in position, stop the boat and lower the anchor slowly over the bow until it reaches the bottom. If anchoring overnight, allow room for the boat to swing as the wind and current may change. You need a larger anchor for overnight use and stormy weather. Lower, never throw, the anchor over the side.
Setting The Anchor
To set the anchor, run the boat slowly astern and let the anchor line run out until its length is about 5 to 7 times the depth of the water plus the height of the bow above the water. Then tie the line to a strong point on the boat’s bow.
As the anchor sets, the bow will turn into the wind and the anchor line will stop jerking. From time to time, check to see that your anchor is holding, not dragging. Use two landmarks to pinpoint your position.
If anchoring at night, you must display an anchor light – a white light visible all round.
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