Sloop

Sloop Rigged Santa Cruz 70 "Retro" off Newport Beach California
The sail plan of a typical "Bermuda" sloop.

A sloop (from Dutch sloep, in turn from French chaloupe) is a sailing boat with a single mast and a fore-and-aft rig. A sloop has only one head-sail; if a vessel has two or more head-sails, the term cutter is used, and its mast may be set further aft than on a sloop.

The most common rig of modern sailboats is the Bermuda-rigged sloop. Typically, a modern sloop carries a mainsail on a boom aft of the mast, with a single loose-footed head-sail (a jib or a genoa) forward of the mast.

Masthead vs. fractional rigging

A masthead-rigged UFO 34

Sloops are either masthead-rigged or fractional-rigged. On a masthead-rigged sloop, the forestay (on which the headsail is carried) attaches at the top of the mast. The mainsail may be smaller than the headsail, which is then called a genoa jib. On a fractional-rigged sloop, the forestay attaches to the mast at a point below the top, typically 3/4 of the way to top, or perhaps 7/8 or some other fraction. Compared to a masthead-rigged sloop, the mast of a fractional-rigged sloop may be placed farther forward; this results in a rather smaller jib relative to the size of the mainsail.

Rationale behind the sloop rig

Typical Bermuda-rigged sloop

After the cat rig which has only a single sail, the sloop rig is one of the simpler sailing rig configurations. A sloop typically has two sails, a mainsail and a headsail (known as either a jib or a genoa, depending on size), while the cutter has a mainsail and two or more headsails. Next in complexity are the ketch, the yawl and the schooner, each of which has two masts and a minimum of three sails. A sloop has a simple system of mast rigging — a forestay (connecting the mast to bow), a backstay (mast to stern) and shrouds (mast to sides).

By having only two sails, the individual sails of a sloop are larger than those of an equivalent cutter, yawl or ketch. Until the advent of lightweight sailcloth and modern sail-handling systems, the larger sails of a sloop could be a handful. So, until the 1950s, sailboats over 10 metres length overall would typically use a cutter rig or a two-mast rig. After the advent of modern winches and light sailcloth, the sloop became the dominant sailing rig type for all but the largest sailboats.

No rig type is perfect for all conditions. Sloops, with their paucity of spars and control lines, tend to impart less aerodynamic drag. Compared to other rigs, sloops tend to perform very well when sailing close hauled to windward and generally offer a sound overall compromise of abilities on all points of sail. Cutters, ketches and yawls are often preferred to sloops when venturing far offshore, because it is easier to reef small sails as the wind increases, while still keeping the boat balanced.

Sails carried

A Marconi rig (Ragtime) designed by John Spencer

To maximize the amount of sail carried, the classic sloop may use a bowsprit, a spar that projects forward from the bow. The foresail may be a jib, which does not overlap the mast more than 10 to 20 percent, or a much larger genoa.[lower-alpha 1] The genoa's large overlap behind the mainsail helps to guide the airflow and thereby makes the mainsail more effective. For downwind sailing, the jib or genoa may be replaced by larger curved sails known as spinnakers or gennakers.

The Bermuda sloop

1883 description of the racing of Bermudian sloops, by Lady Brassey, with illustrations showing the Bermuda rig. The working sloops that were used for weekend races were effectively smaller versions of the ocean-going Bermuda sloop.

Nowadays, by far the most common sloop rig, for yachts, racers and dinghies, is the Bermuda rig,[lower-alpha 2] which is the optimal rig for upwind sailing. Originating from the island of Bermuda in the 17th century, the Bermuda rig is simple, yet may be tuned to be maneuverable and fast. The main disadvantage is the relatively large size of the sails, especially on larger vessels. It is also less successful sailing downwind, when the addition of a spinnaker becomes necessary for faster progress in all but the strongest winds. However, the spinnaker is an intrinsically unstable sail requiring continuous trimming.

An alternative downwind sailplan which is more stable but slower (and thus favored by cruising yachtsmen), is the "wing on wing". Here, the main is swung wide, usually to lee while the jib is swung wide to windward. However the "wing on wing" configuration tends to dip the bow (due to leverage applied lower on a jib than on a spinnaker), requiring crew to move aft to counterbalance the dip; and the combined effect makes the boat ride lower thus being slower due to more hull in contact with water. Also the wing on wing configuration cannot be heeled over to decrease waterline whereas the spinnaker configuration can be. If not tended carefully, the main can go slack even to the point of being dangerously close to jibing. The jib will have that same tendency and being to windward, will snap sharply a-lee but with no boom and being forward of the mast will make for a far less dangerous move than that of the main. A slack main when to leeward can be brought back under control by hauling on the mainsheet to bring it back in contact with the wind when on the aft quarter to windward but if the wind suddenly comes around onto the aft quarter of what had been to lee, the boat must be brought further a-lee (toward what had been windward) to keep the wind strong on the main.

Jamaican sloop

Jamaican sloops[lower-alpha 3][1] had beams that were narrower than ocean-going Bermuda sloops, and could attain a speed of around 12 knots[2] They carried gaff rig, whereas in modern usage, a "Bermuda sloop" excludes any gaff rig. The keel of Jamaican sloops would usually be between 5075 feet, but could be built longer. Jamaican sloops were built near the shore and usually out of cedar trees, for much the same reasons that Bermudian shipwrights favoured the Bermuda cedar (which is actually a juniper): these were very resistant to rot, grew very fast and tall, and had a taste displeasing to marine borers.[3] Cedar was favoured over oak as the latter would rot in about 10 years, while cedar would last for nigh on 30 years and was considerably lighter than oak.[3]

Since piracy was a significant threat in Caribbean waters, merchants sought ships that could outrun pursuers. Ironically, that same speed and maneuverability made them highly prized and even more targeted by the pirates they were designed to avoid. When the ships needed to be de-fouled from seaweed and barnacles, pirates needed a safe haven on which to careen the ship. Sloops were well suited for this because they were able to sail in shallow areas where larger ships would either run aground or be unable to sail through at all. These shallow waters also provided protection from ships of the British Royal Navy, which tended to be larger and required deep water to sail safely.[3]

Historic naval definition

Although the Bermuda sloop is often described as a development of the narrower-beamed Jamaica sloop, which dates from the 1670s, the high, raked masts and triangular sails of its Bermuda rig are rooted in a tradition of Bermudian boat design dating from the early 17th century. Part of that tradition included long, horizontal bowsprits and large jibs. Three jibs were commonly used on Bermudian ships. Triangular sails appeared on Bermudian boats early in the 17th century, a development of the Dutch bezaan, or leg-of-mutton rig, itself derived from the Lateen rig. This became the Bermuda rig, and was appearing on Bermudian ships by the early 19th century. A large spinnaker was carried on a spinnaker boom, when running down-wind.

The naval term "sloop" referred to ships with different rigs and sizes varying from navy to navy. "Sloop-of-war" was more of a reference to the purpose of the craft, rather than to the specific size or sailplan. (Further confusion was caused by the practice of redesignating a vessel simply according to the rank of the commanding officer.) The Royal Navy began buying Bermuda sloops, beginning with an order for three sloops-of-war (HMS Dasher, HMS Driver, and HMS Hunter, which were each of 200 tons, armed with twelve 24 pounders) placed with Bermudian builders in 1795. They were intended to counter the menace of French privateers, which the Navy's ships-of-the-line were ill-designed to counter.

Eventually, Bermuda sloops became the standard advice vessels of the navy, used for communications, reconnoitering, anti-slaving, anti-smuggling, and other roles to which they were well suited. The most notable examples of these "sloops" were HMS Pickle, technically a top sail schooner by modern definition, which raced back to England with news of the British victory and the death of Admiral Lord Horatio Nelson at the end of the Battle of Trafalgar, and HMS Whiting (79 tons and four guns), which lowered anchor in the harbor of Hampton Roads on 8 July 1812, carrying dispatches. The American privateer Dash, which happened to be leaving port, seized the vessel. The crew of Whiting had not yet received news of the American declaration of war, and her capture was the first naval action of the American War of 1812.

Generally, a sloop was smaller than a frigate; however, in the later days of the U.S. Navy's sailing fleet, some of the largest vessels were called sloops because they carried fewer guns than a frigate, as few as 20. The classification of sloop was similar to that of a corvette.

Modern naval definition

HMS Wisteria, an Arabis-class sloop of the Royal Navy, built in 1915 (IWM SP 827)
USS Freedom on sea trials in February 2013 before her first deployment

In modern usage, a sloop refers to a warship between a corvette and a frigate in size. Such vessels were common during the age of steam, but ships of this type were becoming obsolete by the Second World War. The Royal Navy used sloops, such as those of the Flower class (divided into five sub-classes: Acacia, Azalea, Arabis, Aubretia and Anchusa), in numerous roles, including escort duty and anti-submarine warfare, during World War I. The same was true during the Second World War, when the Royal Navy used the Black Swan class. During World War II, Royal Navy sloops destroyed five German submarines.

The new Littoral combat ship (LCS) type of the United States Navy, being intermediate between a frigate and a corvette, is roughly equivalent to a sloop. The U.S. Navy intends these for operations in the littoral zone (close to shore).[4] The type is "envisioned to be a networked, agile, stealthy surface combatant capable of defeating anti-access and asymmetric threats in the littorals." The Freedom class and the Independence class are the first two variants of LCS, and are slightly smaller than the US Navy's guided missile frigates.

Modern civilian connotation

A 20th century International One Design sloop and a 19th-century Bermudian working sloop.

Sloops in their modern form were developed by the French Navy as blockade runners to circumvent Royal Navy blockades. They were later adapted to pilot boats (small ships that took a pilot out to a ship, to guide it into a harbor). Later still, they were adapted to smaller revenue cutters.

The first modern sloops were fitted with the Bermuda rig, so called as a result of its development in Bermuda, during the 17th century. This rig is also called the Marconi rig because of the resemblance of its tall mast and complex standing rigging to Guglielmo Marconi's wireless (radio) transmission antennas.

From 1992 to 2007 International Americas Cup Class sloops sailed in the America's Cup competition. The current Volvo Ocean Race is using a new class, the Volvo Ocean 65, which boasts a canting keel, carbon construction throughout, and very powerful sailplans. The 24-hour distance record was recently broken several times, with ABN AMRO 2 setting the record distance of 563 nautical miles (1,043 km) for a monohull (January 2006). These boats routinely sail at or above wind speeds and can sustain mid-20-knot (37 km/h) speeds hour after hour.

The largest yachting sloop built to date is Mirabella V, with a carbon-fiber mast that is 289 feet (90 m) high.

See also

Notes

  1. For racing rules, a genoa may overlap the mast by 50 to 100 percent, and sometimes even more.
  2. Sometimes known as the Marconi rig, due to its resemblance to the wireless towers of Guglielmo Marconi
  3. The concept of a standard form for a Jamaica sloop is still under debate.

References

  1. http://diginole.lib.fsu.edu/islandora/object/fsu%3A168622
  2. Konstam, Angus. 2007. Pirates: Predators of the Seas. 23–25.
  3. 1 2 3 Evans, Amanda M. 2007. Defining Jamaica Sloops: A Preliminary Model for Identifying an Abstract Concept. Journal of Maritime Archaeology, 2 (2) (October): 83–92.
  4. "US Navy Fact File: LITTORAL COMBAT SHIP CLASS – LCS". Retrieved 8 June 2012.

Bibliography

  • Rousmaniere, John, The Annapolis Book of Seamanship, Simon & Schuster, 1999
  • Chapman Book of Piloting (various contributors), Hearst Corporation, 1999
  • Herreshoff, Halsey (consulting editor), The Sailor’s Handbook, Little Brown and Company, 1983
  • Seidman, David, The Complete Sailor, International Marine, 1995
  • Jobson, Gary, Sailing Fundamentals, Simon & Schuster, 1987

Further reading

  • Jones, Gregory O. (2001). The American Sailboat. MBI Publishing Company. ISBN 978-0-7603-1002-1.
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