A masthead rig on a sailing vessel consists of a

forestay On a sailing vessel, a forestay, sometimes just called a stay, is a piece of standing rigging which keeps a mast from falling backwards. It is attached either at the very top of the mast, or in fractional rigs between about 1/8 and 1/4 from the t ...

and

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 main ...

both attached at the top of the mast. The

Bermuda rig A Bermuda rig, Bermudian rig, or Marconi rig is a configuration of Mast (sailing), 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 1600s; the t ...

can be split into two groups: the masthead rig and the

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. The forestay is a wire that secures the mast to the front of the boat. With a fractional rig, the ...

. 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 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 headsail ...

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 A wind vane, weather vane, or weathercock is an instrument used for showing the direction of the wind. It is typically used as an architectural ornament to the highest point of a building. The word ''vane'' comes from the Old English word , m ...

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.

References

Sailing rigs and rigging {{water-transport-stub

See also

References