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Anchor - Anchor rode

In moderate conditions the ratio of warp to water depth should be 4:1. In rougher conditions it should be up to twice this with the extra length giving more stretch to resist the anchor breaking out. There is little benefit in having a scope of more than 8:1.

Anchor - Danforth anchor

The Fortress is an American aluminum alloy Danforth variant which can be disassembled for storage and it features an adjustable 32° and 45° shank/fluke angle to improve holding capability in common sea bottoms such as hard sand and soft mud. This anchor performed well in a 1989 US Naval Sea Systems Command (NAVSEA) test. and in an August 2014 holding power test that was conducted in the soft mud bottoms of the Chesapeake Bay.

Anchor - Danforth anchor

American Richard Danforth invented the Danforth pattern in the 1940s for use aboard landing craft. It uses a stock at the crown to which two large flat triangular flukes are attached. The stock is hinged so the flukes can orient toward the bottom (and on some designs may be adjusted for an optimal angle depending on the bottom type). Tripping palms at the crown act to tip the flukes into the seabed. The design is a burying variety, and once well set can develop high resistance. Its lightweight and compact flat design make it easy to retrieve and relatively easy to store; some anchor rollers and hawsepipes can accommodate a fluke-style anchor.

Anchor - Stockless anchor

While there are numerous variations, stockless anchors consist of a set of heavy flukes connected by a pivot or ball and socket joint to a shank. Cast into the crown of the anchor is a set of tripping palms, projections that drag on the bottom, forcing the main flukes to dig in.

Anchor - Admiralty Anchor

Since one fluke always protrudes up from the set anchor, there is a great tendency of the rode to foul the anchor as the vessel swings due to wind or current shifts. When this happens, the anchor may be pulled out of the bottom, and in some cases may need to be hauled up to be re-set. In the mid-19th century, numerous modifications were attempted to alleviate these problems, as well as improve holding power, including one-armed mooring anchors. The most successful of these patent anchors, the Trotman Anchor, introduced a pivot where the arms join the shank, allowing the "idle" arm to fold against the shank.

Anchor - Admiralty Anchor

The Admiralty Pattern anchor, or simply "Admiralty", also known as a "Fisherman", consists of a central shank with a ring or shackle for attaching the rode (the rope, chain, or cable connecting the ship and the anchor). At the other end of the shank there are two arms, carrying the flukes, while the stock is mounted to the shackle end, at ninety degrees to the arms. When the anchor lands on the bottom, it will generally fall over with the arms parallel to the seabed. As a strain comes onto the rode, the stock will dig into the bottom, canting the anchor until one of the flukes catches and digs into the bottom.

Anchor - Danforth anchor

The FOB HP anchor designed in Brittany in the 1970s is a Danforth variant designed to give increased holding through its use of rounded flukes setting at a 30° angle.

Anchor - Anchor rode

The anchor rode (or "cable") that connects the anchor to the vessel is made up of chain, sometime with rope ("warp"). Large ships will use only chain rode, whereas, to save weight, smaller boats will use a rope/chain combination. All anchors should have some chain rode; chain is heavy but it resists abrasion from coral, sharp rocks, or shellfish beds, whereas a rope warp is susceptible to abrasion. A combination rode should be arranged so that the rope element should be suspended in the water (and not in contact with the sea bed).

Anchor - Stockless anchor

The stockless anchor, patented in England in 1821, represented the first significant departure in anchor design in centuries. Though their holding-power-to-weight ratio is significantly lower than admiralty pattern anchors, their ease of handling and stowage aboard large ships led to almost universal adoption. In contrast to the elaborate stowage procedures for earlier anchors, stockless anchors are simply hauled up until they rest with the shank inside the hawsepipes, and the flukes against the hull (or inside a recess in the hull).

Anchor - Northill anchor

Originally designed as a lightweight anchor for seaplanes, this design consists of two plough-like blades mounted to a shank, with a folding stock crossing through the crown of the anchor.

Anchor - Anchor rode

Being strong and elastic, nylon rope is very suitable as an anchor warp. Polyester (Terylene) is stronger but less elastic than nylon. Both ropes sink, so they avoid fouling other craft in crowded anchorages and do not absorb much water. Neither breaks down quickly in sunlight. Polypropylene, "polyprop", is not suited to warps as it floats and is much weaker than nylon and barely stronger than natural fibres. Polyprop breaks down in sunlight and becomes hard and unpleasant to handle. Natural fibres such as manila or hemp are still used in developing nations but absorb much water, are relatively weak and rot. They do give good grip and are often very cheap.

Anchor - Admiralty Anchor

The Admiralty Anchor is a reinvention of a classical design, as seen in one of the Nemi ship anchors. This basic design remained unchanged for centuries, with the most significant changes being to the overall proportions, and a move from stocks made of wood to iron stocks in the late 1830s and early 1840s.

Anchor - Delta anchor

The Delta was developed in the 1980s for commercialization by British marine manufacturer Simpson–Lawrence. It is a plough anchor with a rigid, arched shank. It is described as self-launching because it can be dropped from a bow roller simply by paying out the rode, without manual assistance.

Anchor - Anchor rode

All anchors should have chain at least equal to the boat's length. Some skippers prefer an all chain warp for added security in coral waters. Boats less than 8 m typically use 6 mm galvanized chain. 8–14 m craft use 9 mm chain and over 14 m use 12 mm chain. The chain should be shackled to the warp through a steel eye or spliced to the chain using a chain splice. The shackle pin should be securely wired. Either galvanized or stainless steel is suitable for eyes and shackles, galvanised steel being the stronger of the two. Larger yachts may add swivels to the rode. These should not be connected to the anchor itself, but should be somewhere in the chain. Most modern stainless steel swivels will pass easily over windlass gypsies and through hawseholes.

Anchor - Admiralty Anchor

Handling and storage of these anchors requires special equipment and procedures. Once the anchor is hauled up to the hawsepipe, the ring end is hoisted up to the end of a timber projecting from the bow known as the cathead. The crown of the anchor is then hauled up with a heavy tackle until one fluke can be hooked over the rail. This is known as "catting and fishing" the anchor. Before dropping the anchor, the fishing process is reversed, and the anchor is dropped from the end of the cathead.

Anchor - Grapnel anchor

Grapnels rarely have enough fluke area to develop much hold in sand, clay, or mud. It is not unknown for the anchor to foul on its own rode, or to foul the tines with refuse from the bottom, preventing it from digging in. On the other hand, it is quite possible for this anchor to find such a good hook that, without a trip line from the crown, it is impossible to retrieve.

Anchor - CQR plough anchor

A plough anchor has a fundamental flaw: like it namesake, the agricultural plough, it will dig in but then tends to break out back to the surface. Plough anchors sometimes have difficulty setting at all, and instead skip across the seafloor. By contrast, modern efficient anchors tend to be "spade" types that dig ever deeper.

Anchor - Backing an anchor

Also known as tandem anchoring, in this technique two anchors are deployed in line with each other, on the same rode. With the foremost anchor reducing the load on the aft-most, this technique can develop great holding power and may be appropriate in "ultimate storm" circumstances. It does not limit swinging range, and might not be suitable in some circumstances. There are complications, and the technique requires careful preparation and a level of skill and experience above that required for a single anchor.

Anchor - CQR plough anchor

Plough anchors stow conveniently in a roller at the bow, and have been popular with cruising sailors and private boaters. Ploughs are generally good in all types of seafloor, though not exceptional in any. Contrary to popular belief, the CQR's hinged shank is not to allow the anchor to turn with direction changes rather than breaking out, but actually to prevent the shank's weight from disrupting the fluke's orientation while setting. The hinge can wear out and may trap a sailor's fingers. Some later plough anchors have a rigid shank, such as the Lewmar's "Delta".

Anchor (brand) - Anchor Milk

In addition to the common varieties with differing percentages of milk fat, they also offer "Anchor-Xtra", with extra calcium (marketed to "extra active" parents), and "Mega Milk", with extra vitamins, as well as extra calcium, marketed for children. In 2013, the Anchor brand was released in China.