CLANK, CLANK, CLANK … The overwhelming power is hard to describe as a 30-ton Mark 2 Navy Stockless anchor and its over 1,000-foot chain is let go through the hawse pipe in the forecastle aboard the aircraft carrier USS Abraham Lincoln (CVN 72).
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USS Lake Erie (CG-70) Stockless anchor of the Amoco Cadiz in Portsall, north-west Brittany, France A stockless anchor (or "patent anchor") is a streamlined derivation of the traditional Admiralty anchor used aboard large ships. Patented in England in 1821, it eliminated the stock of the Admiralty, making it both easier to handle and stow. Though it did not hold as well as an Admiralty, the trade-off proved acceptable and the stockless anchor became widely popular, and remains so today.
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The club's crest includes stockless anchor with a football ball. The badge shaped like traditional compass with white-green background elements.
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The stockless anchor's ease of stowage and handling saw its widespread adoption in spite of not holding as well as the Admiralty pattern it was derived from The action of a stockless anchor being set The stockless anchor, patented in England in 1821,"anchor" in The New Encyclopædia Britannica. Chicago: Encyclopædia Britannica Inc., 15th edn., 1992, Vol.
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Another advantage of the pivoting shank design is that the anchor generally will still hold even if the wind and or current changes direction and causes the vessel to pull on the anchor from a slightly different angle. Due to the simple design of the stockless anchor, it is capable of free falling much faster in water than other more bulky anchor types according to a study done by The Japan Institute of Navigation. In terms of disadvantages, the stockless anchor is shown to perform poorly in soft cohesive bottoms such as soil or sand compared to other anchor types made specifically for that type of bottom. Also, the Navy Stockless Anchor has an efficiency rate of 4-6, compared to other types of anchors with efficiency rates ranging from 15 to 55.
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The stockless anchor is an improved version of the Admiralty anchor it is derived from. It has two flukes that pivot on the same plane perpendicular to the shank. The weight of the shank and accompanying chain, or the shank angled under tension, keep the anchor laying flat on the sea floor.
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The stockless anchor is simple design with no unnecessary parts. This makes it comparatively easy to handle and store. The simple geometry of its design makes breaking it from the bottom a relatively easy and reliable procedure. The shank being able to pivot while the flukes are embedded in the sea floor minimizes wear on attachment hardware.
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At the beginning of the 20th century, the stockless anchors principally in use in the British navy were Hall's improved, Byer's, and Wasteneys Smith's. Hall's improved stockless anchor In Hall's improved anchor, the arms and crown of cast steel are in one piece, and the shank of forged steel passes up through an aperture in the crown to which it is secured by two cross bolts. Two trunnions or lugs are forged to the lower end of the shank. Byer's stockless anchor In W.L. Byer's plan, the flukes and crown consist of a steel-casting secured to a forged shank by a through bolt of mild steel, the axis of which is parallel to the points of the flukes; one end of the bolt has a head, but the other is screwed and fitted with a phosphor bronze nut to allow the bolt to be withdrawn for examination.
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The cat stopper also fastens the anchor on. The purpose of the cathead is to provide both a heavy enough beam to support the massive weight of the anchor, and to hold the metal anchor away from the wooden side of the ship to prevent damage when the anchor is being raised from the water. The stockless anchor made the cathead obsolete. In common practice, the projecting end of the beam was carved to resemble the face of a lion or cat.
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A stockless anchor being broken out Holding ground in Akaroa Harbour Anchors achieve holding power either by "hooking" into the seabed, or sheer mass, or a combination of the two. Permanent moorings use large masses (commonly a block or slab of concrete) resting on the seabed. Semi-permanent mooring anchors (such as mushroom anchors) and large ship's anchors derive a significant portion of their holding power from their mass, while also hooking or embedding in the bottom. Modern anchors for smaller vessels have metal flukes which hook on to rocks on the bottom or bury themselves in soft seabed.
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A palm is cast on each side of the crown to trip the flukes when the anchor is on the ground, and for bringing them snug against the ship's side when weighing. Wasteneys Smith's stockless anchor Wasteneys Smith's anchor is composed of three main parts, the shank and crown which form one forging, and the two flukes or arms which are separate castings. A bolt passes through the crown of the anchor, connecting the flukes to it; to prevent the flukes working off the connecting through bolt, two smaller bolts pass through the flukes at right angles to the through bolt and are recessed half their diameter into it.
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Stockless anchors have been extensively used in the British mercantile marine and in some other navies. In 1903 they were adopted generally for the British Navy, after extensive anchor trials, begun in 1885. Their advantages are: handiness combined with a saving of time and labor; absence of davits, anchor-beds, and other gear, with a resulting reduction in weight; and a clear forecastyle for "right ahead" gun fire or for working ship. On the other hand, a larger hawsepipe is required, and there appears to be a consensus that a stockless anchor, when "let go" does not hold so quickly as a stocked one, is more uncertain in its action over uneven ground, and is more liable to "come home" (drag).
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