Introduction to anchoring: what it is and why it's essential
The anchor is one of the oldest safety devices in navigation. From the simple stones used by ancient sailors to modern, high-strength steel anchors, its evolution reflects millennia of life at sea. Every type of vessel, from small inflatable boats to sailboats, from artisanal fishing boats to offshore vessels, requires an appropriate anchor. Choosing the wrong one can mean finding yourself adrift at night, posing real risks to the vessel and those on board.
How an anchor works: the principles of seabed grip
An anchor holds a boat through two mechanisms: its weight and its shape. For temporary anchors, it's primarily the shape that does the work: the flukes dig into the seabed and resist the pull exerted by the vessel. The length of chain or rope extended is crucial: the longer it is, the more horizontal the pull is with respect to the seabed. If the length of the rope is too short, the pull angle becomes almost vertical and the anchor tends to "slip," dragging along the seabed without gaining a real hold.
The fundamental parts of a modern anchor
Knowing the parts of a sailboat and its onboard equipment, including the anchor, is the foundation for confident sailing. The spindle is the central bar around which the entire structure is built. The flukes are the arms that extend from the diamond, the junction point, and end in the flaps, the surfaces that bite into the seabed. The nails are the tips of the flaps, those that penetrate the seabed. The cicada is the ring to which the chain attaches, while the stock, the latter present in classic anchors such as the Admiralty, is the crossbar that correctly orients the anchor before it takes hold.
Temporary anchors vs. permanent anchors: knowing them to choose
Temporary anchors: for navigation and temporary stopping
These are the anchors that every yachtsman carries on board and uses daily. The "main anchor" is the one ready for use, normally stored on the bow roller or in the locker; the "reserve anchor" is the reserve, used in critical moments. "Dar fondo" means to lower the anchor to the bottom; "salpare" means to retrieve it. On larger boats, the anchor is stored in the hawse, a special opening in the bow hull.
Permanent anchors: solutions for stable and long-lasting anchoring
These anchors are used to keep buoys, floating docks, or platforms in place for the long term. They are characterized by their very heavy weight: the mushroom anchor and "deadweights"-concrete blocks, rocks, or systems drilled into the seabed-are the most common solutions. Think of the structures that hold up huge boats at anchor, or those that hold professional fishing boats in place in deep waters: when it comes to the largest boats in the world, permanent anchoring systems must support enormous structures. By extension, the term "permanent anchor" also refers to mooring with mooring weights, even if technically it is not a traditional anchor.
The main types of temporary anchors and their applications
The type of boat is the first factor to consider when choosing. There are "latest generation" models and so-called "universal" anchors, but knowing the characteristics of each family remains the foundation for making an informed decision.
Stock anchors (e.g. Admiralty, Northill)
Thanks to their compact flukes and the stock that orients them correctly, this type of anchor works well even on weedy bottoms. Modern models often have a removable stock, which greatly facilitates stowage. They are versatile and suitable for different bottoms, but their weight can be excessive for small boats.
Ploughshare or plough anchors (e.g. CQR, Delta, Kobra, Brake)
Very popular among boaters, these anchors are shaped like a plow: once dragged along the seabed, they stick into the sand or rocks. They work well on many types of seabed, but can have some difficulty on seagrass.
Spoon anchors (e.g. Bruce, Spade, Rocna, Ultra)
Often called "total" anchors due to their effectiveness on almost any penetrable seabed, they originate in some cases from the offshore industry: the Bruce was designed in the 1970s by Peter Bruce specifically for oil rigs in the North Sea. The concave shape ensures a quick and solid hold.
Knuckle fluke anchors (e.g. Danforth, Hall, Fortress)
Their large, flat flukes, which rotate on an axis, make them particularly effective on sand and mud. On rocky or seagrass bottoms, however, they tend to slide without gaining a foothold.
Grapple or umbrella anchors
Regardless of how they strike the bottom, one of the flukes will always catch, which is their main advantage. They are mainly used on small boats. Wide-fluke models are good on sand, mud, and pebbles; narrow-fluke models on hard bottoms. There are collapsible versions, convenient for those with limited space on board, although on uneven rocky bottoms the risk of getting tangled remains real.
Recently developed and dynamically sealed anchors (e.g. Bügel, Spade, Rocna, Ultra, Mantus)
Designed for ease of use and superior holding power, these often patented anchors self-right as they hit the bottom. "Dynamic-holding" anchors stabilize more and more firmly as the load increases, making them virtually impossible to pull away.
Sea anchors and anchors: controlling your vessel in difficult conditions
Sea anchor and stern anchor are different tools, often confused, but both serve to reduce the displacement or speed of the boat in bad weather.
Parachute floating anchor
It is laid at the bow to keep the boat oriented to the sea and wind, preventing it from drifting when the sails are out. The line should be at least ten times the length of the boat, and counterweights can be used to keep it properly immersed.
Drag anchors or floating anchors
The stern stays, usually consisting of a series of cones, are extended from the stern even when the boat is moving, to slow the boat and prevent it from swerving or getting caught in breaking waves. In extreme situations, they can function as an emergency rudder.
Techniques and rules for safe and correct anchoring
How much rope or chain (calumo) should be used for correct anchoring?
The general rule is to cast a line 3-5 times the depth of the seabed under normal conditions, Up to 7-10 times in bad weather or on slippery seabeds. The more line you pull, the more the anchor stays parallel to the bottom and the greater the overall hold. The weight of the chain helps maintain a horizontal pull even with little line pulled.
Types of anchoring
The wheel anchor is the most common: with a single anchor, the boat rotates around the anchor point following the wind and current. With the brush anchors, a second anchor is attached to the diamond of the main one, increasing the hold in rough weather, even if the boat continues to rotate. With the forked anchors, two anchors are arranged at an angle of approximately 45°, limiting the boat's swing and offering greater directional stability.
Practical tips for effective and responsible anchoring
Before dropping anchor, it's always a good idea to consult nautical charts to determine the type of seabed and depth. Anchoring on seagrass, coral, or protected marine areas should be avoided. Those learning to sail a boat or approaching sailing for the first time quickly discover that knowing how to tie sailor's knots is just as useful as choosing the right anchor: knowing the types of knots and understanding, for example, the daisy knot's purpose for shortening a line without cutting it, makes all the difference in managing maneuvers. A good sailor's knot, tied correctly, ensures that the line is securely fastened while anchored. Always evaluate the swing space, regularly check that the anchor is not dragging, and choose sandy or muddy bottoms whenever possible.
Choose the perfect anchor for your boat on Trovobarche.it
The choice of anchor depends on many factors: the size and structure of the boat, the hull of the sailing or motor boat, the usual navigation areas and the seabeds that are most frequently frequented. Those looking for models of sailboats have different needs than those evaluating the best open motorboats for coastal pleasure. The same applies when comparing beginner sailboats with racing boats, or considering the difference in length between a small cabin cruiser and the largest sailboat in the world. On Trovobarche.it, those evaluating a boat for sale should consider the anchor as an integral part of the equipment: a well-sized system speaks volumes about the owner's dedication. Sellers, on the other hand, gain visibility by accurately describing the brand, weight, type, and material of the anchor-details that attract informed buyers.
FAQ
Which anchor should you choose for different types of seabed?
It depends on what's underneath: on sand and mud, anchors with wide flaps usually work best, because they bite hard and grip quickly. On harder bottoms, however, a sharper shape with a pronounced claw that can find a spot to penetrate is often more suitable. Articulated fluke anchors (such as Danforth) are famous for their performance on sand and mud, while plow/share anchors (CQR, Delta, and similar) are often chosen because they adapt well to different situations and are easy to manage in practice. If you navigate in areas with variable bottoms, the latest generation anchors aim to be more "universal" on anything that can be penetrated (sand, mud, gravel), with geometries designed to self-trim.
What is the sea anchor used for?
It's useful when you don't want to "stop" the boat on the bottom, but want to control how much it moves or how fast it goes, especially in rough seas. The parachute sea anchor is usually used on the bow: it opens in the water like a parachute, creating resistance and helping the boat stay more composed, oriented towards the waves and wind. Drag anchors, on the other hand, are more often deployed from the stern: they don't hold the boat still, but slow it down and make it more manageable in rough waves, reducing the risk of sudden movements.
How much rope or chain (calumo) should be used to anchor properly?
As a simple rule of thumb, many boaters think about a line depth of 3–5 times the depth, and it lengthens further if the weather worsens or the bottom "holds poorly." The reason is practical: the more leeway you have in the water, the lower and closer the pull remains to the horizontal with respect to the bottom, and the anchor works better without "jerking" upwards. The chain also helps with its weight: it rests on the bottom, dampens the tugs and maintains the right angle, especially when wind and current change.
