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Sailing rigs (masts and sails) have evolved over many centuries. Different arrangements have been tried, with varying degrees of success. They have changed from being simply structures with large surface areas set up to catch the wind, to more aerodynamic, wing-like structures that generate lift. Here are some of the basic types that use sailcloth supported by different configurations of masts, spars, and battens.

square rig 1
spar top and bottom


  • square rig

It seems probable that the earliest sailing vessels used this type of rig, and they are still used to this day. The sail is supported from the mast by one or more  horizontal spars.

square rig 3

Square-rigged sails are very effective at driving a boat in the direction of the wind, but less successful at gaining ground upwind. One way to improve upwind performance is to attach a bowline to the windward edge of the sail to stabilise it.

  • lug rig

Similar in arrangement to a square rig, except that the supporting spar is asymmetrically arranged on the mast, with a greater length behind than in front. This enables the sail to be used in a more fore-and-aft position to give better upwind performance than the square-rigged sail. Several variations in the cut of the windward edge of the sail have been tried. Tacking involves moving the forward tip of the spar and the attached sail behind the mast to the other side.

lug sail 1
lug sail 2
The junk rig was developed in the far-east. It is distinguished from other lug sails by the use of full-length battens which support the sail and give it an efficient performance at most points of sail. junk rig

  • lateen rig

The lateen rig was developed by Arabic sailors. The name is probably derived from 'Latin'. It has an excellent aerodynamic shape and performs well upwind. However, tacking is a slow process and requires moving the spar and sail to the other side of the mast.

  • gaff rig

The sail is set entirely behind the mast, supported above by a spar which extends upwards and backwards from the mast. There may or may not be another spar at the foot of the sail. This rig is effective at most points of sail.

gaff rig

  • sprit rig

In this rig there is a diagonal spar supporting the top outer corner of the sail away from the mast.

sprit rig

bermudan rig
  • bermudan rig

This is a triangular sail set behind the mast and often supported by a boom along its foot. The mast may be tilted backwards slightly to improve the rig's performance in stronger winds.

The sail behind the mast is often supplemented by one or more sails attached to the forestays of the mast. The picture alongside illustrates a jib.

This gives rise to the popular 'bermudan sloop' rig, with sails fore and aft of the mast. This is an efficient rig on all points of sail.
The gunter rig is similar to the bermudan rig with the exception that the mast is in two parts. The upper part is held vertically against the top of the lower part. This arrangement is helpful when it is necessary for the rig to be dismantled regularly and carried on the boat. gunter rig

  • una rig

This is a sail set behind the mast, like the bermudan rig, but used without a foresail and increasingly without any stays to support the mast. With battens and a curving trailing edge, the sail can be highly efficient and wing-like.

una rig

This configuration is the one most commonly used in the sport of sailboarding. The wishbone boom (purple) supports and tensions the sail away from the back of the mast and also provides handholds for the sailor. The sail shown has full battens.

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