sailboat 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. Types Although sailboat terminology ...

s, a sail batten is a flexible insert in a

sail A sail is a tensile structure, which is 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 b ...

, parallel to the direction of wind flow, that helps shape its qualities as an

airfoil An airfoil (American English) or aerofoil (British English) is a streamlined body that is capable of generating significantly more Lift (force), lift than Drag (physics), drag. Wings, sails and propeller blades are examples of airfoils. Foil (fl ...

. Battens are long, thin strips of material, historically wooden but today usually

fiberglass Fiberglass (American English) or fibreglass (English in the Commonwealth of Nations, Commonwealth English) is a common type of fibre-reinforced plastic, fiber-reinforced plastic using glass fiber. The fibers may be randomly arranged, flattened i ...

vinyl Vinyl may refer to: Chemistry * Polyvinyl chloride (PVC), a particular vinyl polymer * Vinyl cation, a type of carbocation * Vinyl group, a broad class of organic molecules in chemistry * Vinyl polymer, a group of polymers derived from vinyl ...

, or

carbon fiber Carbon fiber-reinforced polymers (American English), carbon-fibre-reinforced polymers ( Commonwealth English), carbon-fiber-reinforced plastics, carbon-fiber reinforced-thermoplastic (CFRP, CRP, CFRTP), also known as carbon fiber, carbon comp ...

, used to support the

roach Roach or The Roach may refer to: Animals * Cockroach, various insect species of the order Blattodea * Common roach (''Rutilus rutilus''), a fresh and brackish water fish of the family Cyprinidae ** ''Rutilus'' or roaches, a genus of fishes * Cal ...

of a sail. They are also used on

tall ships A tall ship is a large, traditionally-rigging, rigged sailing vessel. Popular modern tall ship rigs include topsail schooners, brigantines, brigs and barques. "Tall ship" can also be defined more specifically by an organization, such as for a r ...

to form the ladders up the shrouds in a fashion similar to

ratlines Ratlines () are lengths of thin line tied between the shrouds of a sailing ship to form a ladder. Found on all square-rigged ships, whose crews must go aloft to stow the square sails, they also appear on larger fore-and-aft rigged vessels to ...

History

Battened sails are commonly found in

junk ship A junk () is a type of Chinese sailing ship characterized by a central rudder, an overhanging flat transom, watertight bulkheads, and a flat-bottomed design. They are also characteristically built using iron nails and clamps. The term applies ...

. A junk is an ancient

Chinese Chinese may refer to: * Something related to China * Chinese people, people identified with China, through nationality, citizenship, and/or ethnicity **Han Chinese, East Asian ethnic group native to China. **'' Zhonghua minzu'', the supra-ethnic ...

sailing ship A sailing ship is a sea-going vessel that uses sails mounted on Mast (sailing), masts to harness the power of wind and propel the vessel. There is a variety of sail plans that propel sailing ships, employing Square rig, square-rigged or Fore-an ...

design that is still in use today. Iconographic remains show that Chinese ships before the 12th century used square sails. A ship carving from a stone Buddhist stele shows a ship with square sail from the Liu Sung dynasty or the Liang dynasty (ca. 5th or 6th century). Dunhuang cave temple no. 45 (from the 8th or 9th century) features large sailboats and

sampans A sampan is a relatively flat-bottomed wooden boat found in East, Southeast, and South Asia. It is possibly of Chinese or Austronesian origin. Some sampans include a small shelter on board and may be used as a permanent habitation on in ...

with inflated square sails. A wide ship with a single sail is depicted in the Xi'an mirror (after the 9th or 12th century).See also plates CDIII, CDIV, CDV, CDVI in Needham, Volume 4, Part 3. Eastern

lug sail The lug sail, or lugsail, is a fore-and-aft, four-cornered sail that is suspended from a spar, called a yard. When raised, the sail area overlaps the mast. For "standing lug" rigs, the sail may remain on the same side of the mast on both the port ...

, which used battens and is commonly known as "junk rig", was likely not Chinese in origin: The oldest depiction of a battened junk sail comes from the

Bayon temple The Bayon (, ) ( ''BAI-on'') is a richly decorated Khmer temple related to Buddhism at Angkor in Cambodia. Built in the late 12th or early 13th century as the state temple of the King Jayavarman VII (), the Bayon stands at the centre of Jayav ...

at Angkor Thom, Cambodia.Needham, Joseph (1971).
Science and Civilisation in China: Volume 4, Physics and Physical Technology, Part 3, Civil Engineering and Nautics
'. Cambridge University Press. From its characteristics and location, it is likely that the ship depicted in Bayon was a Southeast Asian ship. The Chinese themselves may have adopted them around the 12th century CE. Their rigs featured full-length battens that facilitated short-handed sail handling, including reefing.

Applications in sails

The most common use of sail battens is in the

of a

mainsail A mainsail is a sail rigged on the main mast (sailing), mast of a sailing vessel. * On a square rigged vessel, it is the lowest and largest sail on the main mast. * On a fore-and-aft rigged vessel, it is the sail rigged aft of the main mast. T ...

. The batten extends the

leech Leeches are segmented parasitism, parasitic or Predation, predatory worms that comprise the Class (biology), subclass Hirudinea within the phylum Annelida. They are closely related to the Oligochaeta, oligochaetes, which include the earthwor ...

past the line that runs from the

head A head is the part of an organism which usually includes the ears, brain, forehead, cheeks, chin, eyes, nose, and mouth, each of which aid in various sensory functions such as sight, hearing, smell, and taste. Some very simple ani ...

and the

clew 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 (e.g. ''fore-and-a ...

of the sail to create a wider sail towards the top. Cruising

s may have four to six battens. Racing sailboats may have full-length battens, as well, that allow for better sail shape. Batten length near the head of the sail is limited by the need for the roach to pass ahead of the

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 ma ...

, when tacking or

jibing A jibe (US) or gybe (Britain) is a sailing maneuver whereby a sailing craft points of sail#Reaching, reaching downwind turns its stern through the wind, which then exerts its force from the opposite side of the vessel. It stands in contras ...

. Battens are also found in jibs of beach-cat catamarans.

Batten materials and construction

Most modern battens are fiberglass

pultrusion Pultrusion is a continuous process for manufacture of fibre-reinforced plastics with constant cross-section. The term is a portmanteau word, combining "pull" and "extrusion". As opposed to extrusion, which pushes the material, pultrusion pulls th ...

s with a thin, rectangular cross section. An alternative shape is a hollow tube that rotates in the batten pocket and is more compatible with roller

furl Furl (from File Uniform Resource Locators) was a free social bookmarking website that allowed members to store searchable copies of webpages and share them with others. Every member received 5 gigabytes of storage space. The site was founded by Mi ...

ing the mainsail. Because the ends of battens are likely to chafe the sail at the ends of the pockets into which they are inserted, they often have a soft, blunt shape affixed to them.

References

{{Sail types Sailing rigs and rigging