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Watchkeeping or watchstanding is the assignment of sailors to specific roles on a ship to operate it continuously. These assignments, also known at sea as watches , are constantly active as they are considered essential to the safe operation of the vessel and also allow the ship to respond to emergencies and other situations quickly. These watches are divided into work periods to ensure that the roles are always occupied at all times, while those members of the crew who are assigned to work during a watch are known as watchkeepers .

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39-450: OOW may refer to: EverQuest: Omens of War , a massively multiplayer online role-playing game (MMORPG) Officer of watch; see Watchstanding Oklahoma Ordnance Works Out of warranty Out Of Work Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with the title OOW . If an internal link led you here, you may wish to change

78-412: 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 Although sailing ships were superseded by engine-powered ships in the 19th century, recreational sailing ships and yachts continue to be designed and constructed.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

117-522: 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,

156-571: 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

195-400: A navy ship) the 4 to 8 watch. The reason for this is to enable the chief mate to assign work to the deck gang before the ship's day begins, and to inspect it before going on watch at 1600 hours. A ship's bell is used in concert with a watch system to indicate the time using bell strikes to mark the time and help sailors know when to change watches. Unlike civil clock bells, the strikes of

234-536: 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

273-432: A ship or boat. Its purposes include carrying sails , spars, and derricks , giving necessary height to a navigation light , look-out position , signal yard , control position , radio aerial or signal lamp . Large ships have several masts, with the size and configuration depending on the style of ship. Nearly all sailing masts are guyed . Until the mid-19th century, all vessels' masts were made of wood formed from

312-412: A ship's bell do not accord to the number of the hour. Instead, there are eight bells, one for each half-hour of a four-hour watch. Bells would be struck every half-hour, and in a pattern of pairs for easier counting, with any odd bells at the end of the sequence. Mizzen The mast of a sailing vessel is a tall spar , or arrangement of spars, erected more or less vertically on the centre-line of

351-436: A single or several pieces of timber which typically consisted of 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

390-463: 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

429-436: 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

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468-402: A watch" in various locations and duties across the ship, such as the bridge and engine room . Typical bridge watchkeepers include a lookout and a deck officer who is responsible for the safe navigation of the ship; whereas in the engine room, an engine officer ensures that running machinery continues to operate within tolerances. A wide variety of types of watches have developed due to

507-540: Is 2 on 4 off during the day (8 a.m. to 8 p.m.) and 3 on 6 off during the night (8 p.m. to 8 a.m.). The same arrangement of watch times can also be used with a crew divided into three sections. This gives each sailor more time off-duty, sometimes allowing sleeping periods of over seven hours. Names for the three watches—instead of Port and Starboard—vary from ship to ship. Naming schemes such as " Foremast ", " Mainmast " and " Mizzen "; and "Tomato", "White" and "Blue" are common. The so-called "five-and-dime" arrangement splits

546-414: Is consistent. For example, a member of watch team 1 will only have to remember that he is on the "4–8" watch, and knows that he goes on watch at 4 a.m. and 4 p.m. This scheme also allows inexperienced watchkeepers to keep watch from 8–12 a.m. and 8–12 p.m., when senior watchkeepers are likely to be awake and ready to assist in case of trouble. By custom, in a ship with five deck officers

585-431: Is the mainmast. This contrasts with 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

624-601: 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

663-533: 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

702-472: 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

741-471: 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

780-404: The ability for the ship to function. Meals are generally scheduled around the watch turnovers at 0700, 1200, and 1700; sometimes a light midnight meal known as mid-rats (midnight rations) is provided for the 0000 turnover. Various alternative watch schedules have been devised, which are typically referred to as Swedish watches . Although there is no standard for what constitutes a Swedish watch,

819-423: 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 ,

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858-406: The day into five-hour watches, with the exception of a four-hour watch from 22:00 to 02:00. The "six-hour shift" splits the day into four six-hour watches, permitting a three-section crew to maximize rest time in a three-day working cycle. Also, this watch system takes into better account the meal times (of a four-meals-a-day system), so that the ingoing team will be fed first, then keep watch, while

897-444: The deck, into which a mast is fixed, with 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

936-623: The different needs aboard merchant and naval vessels. This table gives some examples: Enlisted Enlisted A watch system, watch schedule, or watch bill is a method of assigning regular periods of watchkeeping duty aboard ships and some other areas of employment. A watch system allows the ship's crew to operate the ship 24 hours a day while also allowing individual personnel adequate time for rest and other duties. Watch durations vary between vessels due to some reasons and restrictions; some watch systems aim to ensure that each team takes turns to work late at night, while other systems ensure

975-495: 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

1014-409: The first 6 hours being used for maintenance, cleaning, and entertainment; while the second 6 hours were usually for sleeping. Note that this arrangement resulted in one of the sections having two watches in one (24-hour) day, and there were no dog watches. Also, watch reliefs occurred no later than the bottom of the hour (2330, 0530, 1130, 1730). Typically, the first 30 minutes of the hour were used for

1053-476: 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

1092-399: The junior third mate takes the 8 to 12 watch, the senior third mate the 12 to 4 watch, and the second mate the 4 to 8 watch. This enables the second officer, who is the ship's navigator, to take morning and evening star sights. In ships with only four deck officers, the third officer will keep the 8 to 12, the second officer the 12 to 4, and the chief mate (equivalent to the executive officer in

1131-496: The late 19th century and was used by the Royal Navy and many other Commonwealth navies. It consisted of 5 four-hour periods and 2 two-hour periods. Those members of the crew whose work must be done at all times of the day were assigned to one of two divisions: the starboard or the port division. These can be further divided into two parts, e.g., First Port, Second Starboard. The Royal Navy traditional submarine three watch system

1170-471: 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,

1209-430: The link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=OOW&oldid=1048085331 " Category : Disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages Watchstanding On a typical seafaring vessel, be it naval or merchant, personnel "keep

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1248-494: The lower sections sufficient thickness necessitated building them up from separate pieces of wood. Such 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

1287-405: The naming 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

1326-407: The oncoming section to eat while the second 30 minutes of the hour were used for the off-going section to eat. Some warships now use the one-in-two system, also known as 7s and 5s, for the duration of the watches. This watch system is also sometimes referred to as Port and Starboard watches. This gives the sailors a longer sleeping period than the traditional two-watch system, while still maintaining

1365-497: The outgoing team will be relieved of watch, and then proceed to the mess deck. Aboard United States submarines , the crew is typically divided into three sections, with each section keeping 8 hours of watch followed by 16 hours off-watch. This schedule has been a fairly recent change to submariner work and rest routines. For nearly 45 years before 2015, submariners were on 18-hour days with 6 hours of watch followed by 12 hours off watch. The 12 hours off-watch were further divided into

1404-405: 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

1443-450: The same team consistently works at the same hours every day. Many watch systems incorporate the concept of a dog watch , whereby one watch is split into two shorter watches so that there is an odd number each day. Doing so allows crew members to have a different watch schedule each day. Often, the dog watches are set at dinner time to allow the entire crew to be fed in short order. The traditional watch system arose from sailing ships of

1482-402: The variations all feature some element of extended watches to accommodate longer time off. Like the traditional watch system, they begin at 0000 hours. Some popular variations have durations of 6, 6, 4, 4, 4 and 5, 5, 5, 5, 4. On merchant ships , watchkeepers typically keep watch for six periods of four consecutive hours. This system has a couple of advantages: it is easy to remember and it

1521-402: Was found convenient to dispense with 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

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