Misplaced Pages

#539460

35-549: RV Atlantis was a ketch rigged research vessel operated by the Woods Hole Oceanographic Institution from 1931 to 1966. The Government of Argentina's National Scientific and Technical Research Council acquired her in 1966 and renamed her El Austral , transferring her to the Argentine Naval Prefecture in 1996 as the training and survey ship PNA Dr. Bernardo Houssay (MOV-1). In 2005 it

70-432: A ketch or a yawl , where the after mast, and its principal sail, is clearly the smaller of the two, so the terminology is (from forward) mainmast and mizzen. (In a yawl, the term "jigger" is occasionally used for the aftermast.) Some two-masted luggers have a fore-mast and a mizzen-mast – there is no main-mast. This is because these traditional types used to have three masts, but it was found convenient to dispense with

105-461: A brief period of renewed interest in the 1970s and 1980s as carbon fiber spars made free-standing mast versions of this rig possible for cruising boats under 40 feet. Staysails can also be hoisted between the top of the mizzen mast and base of the mainmast to help downwind performance. Mast (sailing) Until the mid-19th century, all vessels' masts were made of wood formed from a single or several pieces of timber which typically consisted of

140-412: A century later, the simple box form of mast was arrived at. Although sailing ships were superseded by engine-powered ships in the 19th century, recreational sailing ships and yachts continue to be designed and constructed. In the 1930s aluminum masts were introduced on large J-class yachts . An aluminum mast has considerable advantages over a wooden one: it is lighter and slimmer than a wooden one of

175-522: A fundamental transformation in Mediterranean navigation: the lateen which had long evolved on smaller Greco-Roman craft replaced the square rig , the chief sail type of the ancients, that practically disappeared from the record until the 14th century (while it remained dominant in northern Europe). The dromon , the lateen-rigged and oared bireme of the Byzantine navy , almost certainly had two masts,

210-402: A ketch is rigged so that it can fly multiple jibs at the same time, the rig is sometimes referred to as a multi-headsail ketch. While sometimes seen in print, it is incorrect to refer to this rig by the modern malaprop of a cutter ketch . In New England in the 1600s, the ketch was a small coastal working watercraft. In the 1700s, it disappeared from contemporary records, apparently replaced by

245-571: A larger foremast and one midships. Their length has been estimated at 12 m and 8 m respectively, somewhat smaller than the Sicilian war galleys of the time. Multiple-masted sailing ships were reintroduced into the Mediterranean Sea by the Late Middle Ages . Large vessels were coming more and more into use and the need for additional masts to control these ships adequately grew with

280-401: A pivot near the top so that the mast can be lowered"; "large bracket attached firmly to the deck, to which the foot of the mast is fixed; it has two sides or cheeks and a bolt forming the pivot around which the mast is raised and lowered"; "substantial fitting for mounting the mast on deck, so that it can be lowered easily for trailering or for sailing under bridges", "hinged device allowing for

315-536: A prestige object commissioned by king Hiero II of Syracuse and devised by the polymath Archimedes around 240 BC, and other Syracusan merchant ships of the time. The imperial grain freighters travelling the routes between Alexandria and Rome also included three-masted vessels. A mosaic in Ostia (c. 200 AD) depicts a freighter with a three-masted rig entering Rome's harbour. Special craft could carry many more masts: Theophrastus ( Hist. Plant. 5.8.2) records how

350-400: A section was known as a made mast , as opposed to sections formed from single pieces of timber, which were known as pole masts . Those who specialised in making masts were known as mastmakers . For square-sail carrying ships , masts in their standard names in bow to stern (front to back) order, are: Some names given to masts in ships carrying other types of rig (where the naming

385-463: A sizable foresail rigged on a slightly inclined foremast is depicted in an Etruscan tomb painting from 475 to 450 BC. An artemon ( Greek for foresail) almost the same size as the galley 's mainsail can be found on a Corinthian krater as early as the late 6th century BC; apart from that Greek longships are uniformly shown without it until the 4th century BC. In the East, ancient Indian Kingdoms like

SECTION 10

#1732880939540

420-436: A steel mast of an equivalent strength can be smaller in diameter than an aluminum mast, allowing less turbulence and a better airflow onto the sail. From the mid-1990s racing yachts introduced the use of carbon fibre and other composite materials to construct masts with even better strength-to-weight ratios. Carbon fibre masts could also be constructed with more precisely engineered aerodynamic profiles. Modern masts form

455-622: Is a two- masted sailboat whose mainmast is taller than the mizzen mast (or aft-mast), and whose mizzen mast is stepped forward of the rudder post . The mizzen mast stepped forward of the rudder post is what distinguishes the ketch from a yawl , which has its mizzen mast stepped aft of its rudder post. In the 19th and 20th centuries, ketch rigs were often employed on larger yachts and working watercraft, but ketches are also used as smaller working watercraft as short as 15 feet, or as small cruising boats, such as Bill Hanna's Tahiti ketches or L. Francis Herreshoff's Rozinante and H-28. The name ketch

490-417: Is derived from catch . The ketch's main mast is usually stepped further forward than the position found on a sloop . The sail plan of a ketch is similar to that of a yawl , on which the mizzen mast is smaller and set further back. There are versions of the ketch rig that only have a mainsail and a mizzen, in which case they are referred to as cat ketch . More commonly ketches have headsails (Jibs). When

525-431: Is less standardised) are: When a vessel has two masts, as a general rule, the main mast is the one setting the largest sail. Therefore, in a brig , the forward mast is the foremast and the after mast is the mainmast. In a schooner with two masts, even if the masts are of the same height, the after one usually carries a larger sail (because a longer boom can be used), so the after mast is the mainmast. This contrasts with

560-601: The Kalinga from as early as 2nd century are believed to have commanded naval sail ships. One of the earliest documented evidence of Indian sail building comes from the mural of the three-masted ship in Ajanta caves that date back to 400–500 CE. The foremast became fairly common on Roman galleys , where, inclined at an angle of 45°, it was more akin to a bowsprit , and the foresail set on it, reduced in size, seems to be used rather as an aid to steering than for propulsion. While most of

595-606: The National Scientific and Technical Research Council ( Consejo Nacional de Investigaciones Científicas y Técnicas - CONICET). She entered service in 1966 as the research vessel El Austral with CONICET, operated by the Argentine Navy as ARA El Austral (Q-47) and carrying our important investigations in the Argentine Sea . After the purpose-built ice-strengthened research ship ARA Puerto Deseado (Q-20) took over as

630-533: The Romans imported Corsican timber by way of a huge raft propelled by as many as fifty masts and sails. Throughout antiquity , both foresail and mizzen remained secondary in terms of canvas size, although large enough to require full running rigging . In late antiquity , the foremast lost most of its tilt, standing nearly upright on some ships. By the onset of the Early Middle Ages , rigging had undergone

665-472: The pintle -and- gudgeon rudder , all advanced ship design technology necessary for the great transoceanic voyages was in place by the beginning of the 15th century. The first hollow mast was fitted on the American sloop Maria in 1845, 28 m (92 ft) long and built of staves bound with iron hoops like a barrel. Other hollow masts were made from two tapered timbers hollowed and glued together. Nearly

700-581: The schooner . The ketch rig remained popular in America throughout the 19th and early 20th century working watercraft, with well-known examples being the Chesapeake Bay bugeyes, New Haven sharpies, and the Kingston Lobster boats. In Europe, during this same period many of the canoe yawls were technically ketches since their mizzen masts were located forward of the rudder posts. The cat ketch rig experienced

735-529: The 1930 ship. Tandanor built the new hull, with lower draught incorporating a much increased accommodation for scientists, between 2007 and 2009 at the Tandanor shipyard in Buenos Aires . Also fitted were a new main engine, generators, shaft and propeller, safety equipment, air-conditioning, and all safety and navigation equipment The new ship was commissioned into PNA service in 2011. Ketch A ketch

SECTION 20

#1732880939540

770-555: The Institution to locate and describe the first abyssal plain in the summer of 1947. This plain, located to the south of Newfoundland , is now known as the Sohm Abyssal Plain . Following this discovery many other examples were found in all the oceans. Atlantis made 299 cruises and covered 700,000 miles, carrying out all types of ocean science. In 1964, Atlantis was offered to the government of Argentina and refurbished for

805-471: The West, the concept of a ship carrying more than one mast, to give it more speed under sail and to improve its sailing qualities, evolved in northern Mediterranean waters: The earliest foremast has been identified on an Etruscan pyxis from Caere , Italy , dating to the mid-7th century BC: a warship with a furled mainsail is engaging an enemy vessel, deploying a foresail . A two-masted merchant vessel with

840-423: The ancient evidence is iconographic, the existence of foremasts can also be deduced archaeologically from slots in foremast-feets located too close to the prow for a mainsail. Artemon , along with mainsail and topsail , developed into the standard rig of seagoing vessels in imperial times , complemented by a mizzen on the largest freighters. The earliest recorded three-masters were the giant Syracusia ,

875-495: The easy folding of a mast 90 degrees from perpendicular, as for transporting the boat on a trailer, or passing under a bridge" The oldest evidence for the use of masts comes from the Ubaid period site of H3 in Kuwait, dating to the second half of the sixth millennium BC. Here, a clay disc made from a sherd that appears to depict a reed bundle boat with two masts has been recovered. In

910-463: The first ship built specifically for interdisciplinary research in marine biology , marine geology and physical oceanography . The 460-ton Marconi-rigged ketch originally carried a crew of 17 and had room for 5 scientists. Columbus Iselin II, her first master and a major influence in her design, felt that steadiness, silence and cruising range were of greater importance than speed. After her construction

945-476: The increase in tonnage. Unlike in antiquity, the mizzen-mast was adopted on medieval two-masters earlier than the foremast, a process which can be traced back by pictorial evidence from Venice and Barcelona to the mid-14th century. To balance out the sail plan the next obvious step was to add a mast fore of the main-mast, which first appears in a Catalan ink drawing from 1409. With the three-masted ship established, propelled by square rig and lateen, and guided by

980-471: The leading edge of a sail's airfoil and tend to have a teardrop-shaped cross-section. On smaller racing yachts and catamarans, the mast rotates to the optimum angle for the sail's airfoil. If the mast has a long, thin cross-section and makes up a significant area of the airfoil, it is called a wing-mast; boats using these have a smaller sail area to compensate for the larger mast area. There are many manufacturers of modern masts for sailing yachts of all sizes,

1015-407: The main-mast and carry larger sails on the remaining masts. This gave more working room, particularly on fishing vessels. On square-rigged vessels, each mast carries several horizontal yards from which the individual sails are rigged . Folding mast ships use a tabernacle anchor point. Definitions include: "the partly open socket or double post on the deck, into which a mast is fixed, with

1050-580: The platform for CONICET's projects in December 1978, El Austral was decommissioned from the navy and laid up with a skeleton crew at Puerto Madryn . In 1995, CONICET reached agreement to transfer El Austral to the Argentine Naval Prefecture ( Prefectura Naval Argentina - PNA) and renamed PNA Dr. Barnardo Houssay (MOV-1), after the eminent physiologist and director of CONICET. However, she remained berthed in Dock E, Buenos Aires, out of use, until 2005, when she

1085-405: The same strength, is impervious to rot, and can be produced as a single extruded length. During the 1960s wood was eclipsed by aluminum. Aluminum alloys, generally 6000 series, are commonly utilised. Recently some sailing yachts (particularly home-built yachts) have begun to use steel masts. Whilst somewhat heavier than aluminum, steel has its own set of advantages. It is significantly cheaper, and

RV Atlantis - Misplaced Pages Continue

1120-475: The trunk of a conifer tree. From the 16th century, vessels were often built of a size requiring masts taller and thicker than from single tree trunks. On these larger vessels, to achieve the required height, the masts were built from up to four sections (also called masts). From lowest to highest, these were called: lower, top, topgallant, and royal masts. Giving the lower sections sufficient thickness necessitated building them up from separate pieces of wood. Such

1155-411: Was complete, WHOI searched for an appropriate name for the new vessel. Alexander Forbes (1882–1965), a trustee of WHOI, had recently bought a schooner named Atlantis from Iselin. Forbes rechristened his schooner so the new research vessel could be named Atlantis . Use of a continuously recording fathometer on Atlantis cruise No. 150 enabled Ivan Tolstoy, Maurice Ewing , and other scientists of

1190-573: Was decided that a replacement vessel with modern capabilities and equipment was required, and a new ship was built in Argentina with a hull and rig along similar lines. Ceremonially incorporating some small parts of the original, she was completed in 2009 and put into full service in 2011, again as Dr. Bernardo Houssay . Atlantis was the first research vessel of the American Woods Hole Oceanographic Institution (WHOI) and

1225-412: Was moved to the nearby Tandanor shipyard with a view to restoring her to active service as a training ship. The PNA reached the conclusion that the ship's condition, after the long periods laid up, could no longer meet its developing requirements, including modern safety and navigation standards, and they decided to build a new ship, albeit largely to the same design, and incorporating some components from

#539460