Masthead rig

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A UFO 34 an example of a masthead-rigged yacht Amadeus sailing (UFO 34).jpg
A UFO 34 an example of a masthead-rigged yacht

A masthead rig on a sailing vessel consists of a forestay and backstay both attached at the top of the mast. [1]

The Bermuda rig can be split into two groups: the masthead rig and the fractional rig. The masthead rig has larger and more headsails, and a smaller mainsail, compared to the fractional rig.

The major advantage a masthead sloop has over a fractional one, is that the jib is larger. Since the jib has no mast in front of it to cause turbulent airflow over it, it is considered much more efficient than the main, especially for sailing up wind. Also, since the fore stay is attached to the top of the mast, it pulls directly against the back stay. Tightening the back stay, then, increases the tension on the fore stay. This is useful because the jib needs considerable fore stay tension to set well. This need increases in direct proportion to the wind speed and jib size. Increasing the tension on the back stay does not tend to bend the mast, as it would on a fractional sloop. It puts the mast in compression instead. For this reason the mast on a mast head rig has a thicker section at the top to stand this load.

One reason this rig is used on oceangoing boats is that it can be made quite strong, as every part of it, except the boom, is in either tension or compression. This rig requires a much stiffer hull than a fractional sloop rig to take these rigging loads, so is not well suited for lightly built boats.

A major disadvantage is that, to shorten sail, the jib must be reefed as well as the main. If the jib is taken in and the main left standing, the main will have a strong tendency to weathercock the boat into the wind, making it uncontrollable. There are four typical remedies used: 1.) put reef points in the jib, 2.) have a smaller jib to set in place of the full sized one, 3.) have a roller furling mechanism that rolls up the jib like window shade, and 4.) have two jibs instead of one (often referred to as a 'cutter' rig), so one of the jibs can be taken in.

See also

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A sloop is a sailboat with a single mast typically having only one headsail in front of the mast and one mainsail aft of (behind) the mast. Such an arrangement is called a fore-and-aft rig, and can be rigged as a Bermuda rig with triangular sails fore and aft, or as a gaff-rig with triangular foresail(s) and a gaff rigged mainsail. Sailboats can be classified according to type of rig, and so a sailboat may be a sloop, catboat, cutter, ketch, yawl, or schooner. A sloop usually has only one headsail, although an exception is the Friendship sloop, which is usually gaff-rigged with a bowsprit and multiple headsails. If the vessel has two or more headsails, the term cutter may be used, especially if the mast is stepped further towards the back of the boat.

Sailboat Boat propelled partly or entirely by sails

A sailboat or sailing boat is a boat propelled partly or entirely by sails and is smaller than a sailing ship. Distinctions in what constitutes a sailing boat and ship vary by region and maritime culture.

Sail plan Diagram of the masts, spars, rigging, and sails of a sailing vessel

A sail plan is a description of the specific ways that a sailing craft is rigged. Also, the term "sail plan" is a graphic depiction of the arrangement of the sails for a given sailing craft.

A jib is a triangular sail that sets ahead of the foremast of a sailing vessel. Its tack is fixed to the bowsprit, to the bows, or to the deck between the bowsprit and the foremost mast. Jibs and spinnakers are the two main types of headsails on a modern boat.

Jibe Basic sailing maneuver, where ship turns its stern through the wind

A jibe (US) or gybe (Britain) is a sailing maneuver whereby a sailing vessel reaching downwind turns its stern through the wind, which then exerts its force from the opposite side of the vessel. For square-rigged ships, this maneuver is called wearing ship.

Backstay

A backstay is a piece of standing rigging on a sailing vessel that runs from the mast to either its transom or rear quarter, counteracting the forestay and jib. It is an important sail trim control and has a direct effect on the shape of the mainsail and the headsail. Backstays are generally adjusted by block and tackle, hydraulic adjusters, or lines leading to winches.

Spinnaker Sail designed for sailing off the wind

A spinnaker is a sail designed specifically for sailing off the wind from a reaching course to a downwind, i.e. with the wind 90–180° off bow. The spinnaker fills with wind and balloons out in front of the boat when it is deployed, called flying. It is constructed of lightweight fabric, usually nylon, and is often brightly colored. It may be optimised for a particular range of wind angles, as either a reaching or a running spinnaker, by the shaping of the panels and seams.

Mainsail Sail rigged to the main mast of a sailing vessel

A mainsail is a sail rigged on the main mast of a sailing vessel.

Cutter (boat) Type of boat

A cutter is a type of watercraft. The term has several meanings. It can apply to the rig of a sailing vessel, to a governmental enforcement agency vessel, to a type of ship's boat which can be used under sail or oars, or, historically, to a type of fast-sailing vessel introduced in the 18th century, some of which were used as small warships.

Gaff rig Sailing rig configuration

Gaff rig is a sailing rig in which the sail is four-cornered, fore-and-aft rigged, controlled at its peak and, usually, its entire head by a spar (pole) called the gaff. Because of the size and shape of the sail, a gaff rig will have running backstays rather than permanent backstays.

Bermuda rig Configuration of mast and rigging for a type of sailboat

A Bermuda rig, Bermudian rig, or Marconi rig is a configuration of mast and rigging for a type of sailboat and is the typical configuration for most modern sailboats. This configuration was developed in Bermuda in the 17th century; the term Marconi, a reference to the inventor of the radio, Guglielmo Marconi, became associated with this configuration in the early 20th century because the wires that stabilize the mast of a Bermuda rig reminded observers of the wires on early radio masts.

Square rig Generic type of sail and rigging arrangement

Square rig is a generic type of sail and rigging arrangement in which the primary driving sails are carried on horizontal spars which are perpendicular, or square, to the keel of the vessel and to the masts. These spars are called yards and their tips, beyond the last stay, are called the yardarms. A ship mainly rigged so is called a square-rigger.

Sail components Features that define a (ship) sails shape and function

Sail components include the features that define a sail's shape and function, plus its constituent parts from which it is manufactured. A sail may be classified in a variety of ways, including by its orientation to the vessel and its shape,. Sails are typically constructed out of flexible material that is shaped by various means, while in use, to offer an appropriate airfoil, according to the strength and apparent direction of the wind. A variety of features and fittings allow the sail to be attached to lines and spars.

Boom (sailing) In sailing, a spar along the bottom edge of a fore and aft rigged sail

In sailing, a boom is a spar (pole), along the foot of a fore and aft rigged sail, that greatly improves control of the angle and shape of the sail. The primary action of the boom is to keep the foot flatter when the sail angle is away from the centerline of the boat. The boom also serves as an attachment point for more sophisticated control lines. Because of the improved sail control it is rare to find a non-headsail without a boom, but lateen sails, for instance, are loose-footed. In some modern applications, the sail is rolled up into the boom for storage or reefing.

Running backstays support the headstay in a fractionally rigged boat. A masthead rig has the advantage of not needing them. A running backstay runs from each lateral corner of the stern to the mast at the level where the forestay begins in the fractional rig. Together with other rigging, it supports the mast. Because they are attached low on mast, they can present a significant problem in an accidental gybe, as the boom hits the stay, with the possibility of breaking the boom, mast, or both.

Fractional rig

A fractional rig on a sailing vessel consists of a foresail, such as a jib or genoa sail, that does not reach all the way to the top of the mast.

Junk rig Type of sail rig used in the Junk ships of dynastic China

The junk rig, also known as the Chinese lugsail or sampan rig, is a type of sail rig in which rigid members, called battens, span the full width of the sail and extend the sail forward of the mast.

A mast-aft rig is a sailboat sail-plan that uses a single mast set in the aft half of the hull. The mast supports fore-sails that may consist of a single jib, multiple staysails, or a crab claw sail. The mainsail is either small or completely absent. Mast-aft rigs are uncommon, but are found on a few custom, and production sailboats.

Sail Fabric or other surface supported by a mast to allow wind propulsion

A sail is a tensile structure—made from fabric or other membrane materials—that uses wind power to propel sailing craft, including sailing ships, sailboats, windsurfers, ice boats, and even sail-powered land vehicles. Sails may be made from a combination of woven materials—including canvas or polyester cloth, laminated membranes or bonded filaments—usually in a three- or four-sided shape.

A solent refers to a sail and rigging system on sailboats, typically sloops. Sailors, particularly French sailors, often refer to a 100% jib as a Solent, because its smaller size is preferable when sailing in the strong winds found in the Solent between the Isle of Wight and Britain. The common use of roller-furling headsails, or genoas, on modern cruising yachts allows the jib to be reduced in size, but partially-furled sails lack the efficiency of a sail that is actually cut to a smaller size. Accordingly, it is preferable to fly a separate, smaller jib—the solent—instead.

References

  1. Dedekam, Ivar (2000). Sail and Rig Tuning. John Wiley & Sons. p. 62. ISBN   1-898660-67-0.