Anchor System Terminology and Gear

Safely and successfully anchoring a boat depends on selecting the proper anchor, choosing a good site, and linking the two through an effective connection that starts on the deck and reaches to the water’s bottom with a secured anchor. Effective anchoring preparation includes knowing anchoring terminology.

Ground Tackle & Anchor Rode– An anchor and the gear attached to it is known as ground tackle. The resulting connection made from the boat to the anchor is called the anchor rode. Ground tackle is selected to meet a number of requirements: it needs to encourage an anchor to hold on the bottom, absorb shock loads, and hold a boat securely without failing.

Stock & Flukes- An effective rode is typically formed from a combination of chain and line. Fastening an initial length of chain to an anchor helps keep the anchor’s stock parallel to the bottom, which keeps its flukes engaged with the bottom (the stock is the long arm of the anchor that has the flukes on one end and a connecting point for the rode on the other).

Anchor Chain & Line-The anchor chain is joined with an anchor line that forms the greater proportion of the rode. Most boaters find that nylon lines works well as anchor lines, as nylon is strong, long lasting and readily adsorbs shocks applied to the rode.

Rode Length & Scope – Water depth, bottom conditions and weather determine the rode length or scope needed to secure a vessel. The longer the rode, the closer an anchor stock will lay parallel to the bottom, making the anchor less likely to drag. The length of rode used to anchor a boat is known as scope and is expressed as a ratio. Under ideal conditions, with a good holding bottom and fair weather, a scope of five times the water depth (5:1) might suffice. As an example, a 5:1 scope in 50 feet of water would require 250 feet of rode. However, most experienced boaters favor using more scope than necessary to anchor their boats; conventional wisdom calls for normal use of a 7:1 rode, and during heavy weather, a 10:1 ratio may not be enough.

As you put together your vessel’s ground tackle, pay close attention to how connections are made between the different components. Use corrosion resistant clevises and safety wire to make chain to anchor attachments. Consider using an eye splice in the anchor line, rather than a knot to connect with the anchor chain.

Be sure everything is securely connected from the anchor to the deck of the boat before an anchor is finally deployed. More than one boater has lost an anchor overboard because the anchor line wasn’t actually secured to the deck cleat! When you take time to think about, prepare and check over your anchoring system, it is more likely you will have a safe and successful outing.

By Alan Sorum

Editor’s Note: Look on our website for a previous article by Alan Sorum on Boat Anchors: An Essential Necessity, which detailed the types of anchors for Long Island’s waters.