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38-436: An oar is a tool used for rowing a boat. OAR or oar may also refer to: Oar The difference between oars and paddles is that oars are used exclusively for rowing . In rowing the oar is connected to the vessel by means of a pivot point for the oar, either an oarlock , or a thole. The oar is placed in the pivot point with a short portion inside the vessel, and a much larger portion outside. The rower pulls on

76-471: A Hemudu culture site at Yuyao , Zhejiang , in modern China. In 1999, an oar measuring 63.4 cm (2 ft) in length, dating from 4000 BC, was unearthed in Ishikawa Prefecture , Japan. Oars have traditionally been made of wood. The form is a long shaft (or loom) with a flat blade on the end. Where the oar connects to the boat there is a "collar" (or button), often made of leather, which stops

114-421: A boat using an outboard or other motor and must be inspected. Stainless steel should never be used for fittings permanently in the water. Owners should check that the correct grade of stainless steel is used in a fitting. Working boats may use lower-cost galvanized steel , but the hardware may need to be re-galvanized or replaced eventually. The dinghy is generally carried inverted amidships on yachts, on top of

152-426: A dinghy will have an oar on each side. A single sculling oarlock or notch on the transom is less common, but requires less space; and is used with a single sculling oar moving back and forth, never leaving the water, as used on a sampan . Many modern dinghies are made of synthetic materials. These require minimal care and do not rot but can suffer from fibre glass pox which is caused by the ingress of saltwater through

190-410: A dinghy. If a dinghy is towed, an extra line with a loop in the end (known as a lazy painter) can be attached to a dinghy so that if the towing line breaks, there is a line to grab with a boat hook. This makes retrieval easier at sea, especially if the boat is partially swamped. In some countries dinghies have names or registration numbers. On hard dinghies these are usually on the bow, on inflatables on

228-400: A hard V-bottom hull and a fifteen-horsepower (11 kW) outboard can reach speeds of 25 mph (40 km/h; 22 kn). The gas tank is usually placed under the rear thwart. Engines always swing up so the dinghy can be grounded without damage. Since the transom may need to be cut down for the engine to fit properly, an engine well should be used to prevent low waves from splashing over

266-418: A larger dinghy. Space can be saved by storing items in containers or bags that are tied to the dinghy. Dinghies are sometimes used as lifeboats. Recently, self-rescue dinghies have returned to use as proactive lifeboats that can be sailed to safety. Rigid dinghies for small yachts are very small, about 2 m (6 ft 6 + 3 ⁄ 4  in), usually with a pram (blunt) bow to get more beam (width) in

304-460: A range of uses. Some are intended as a tender for a larger vessel. Others are small utility boats, used where a larger boat is not needed. Many are designed primarily for sailing. These fall into two groups: those intended for racing and those for non-competitive leisure use. A rigid-hulled dinghy can be made of wood (using either traditional or modern techniques), fibreglass or, more recently, moulded polypropylene. Inflatable dinghies solve some of

342-417: A rower to operate without fatigue. The two methods of adding weight are to either have a much larger section in the oar immediately next to the handle for a distance of about 450 millimetres (18 in) or to drill an 18-millimetre (0.71 in) hole inside the handle for a distance of about 150 millimetres (5.9 in) and add about 12 oz of lead secured by epoxy resin glue. For a 7-foot (2.1 m) oar

380-439: A sectional two-piece rigid dinghy that is towed while in harbour and disassembled into two nesting pieces while off-shore; typically the bow section fits inside the stern and is stored upside down on deck. There are several types of collapsible rigid dinghy that dismantle into a series of flat panels for easy stowage. Inflatable tubes can be fitted to an existing hard dinghy, increasing buoyancy and stability. A dinghy should have

418-466: A shorter length. Larger dinghies are towed and should have reserve buoyancy, an automatic bailer, and a cover to prevent them from being lost at sea. Most masters prefer a tow cable long enough to put the dinghy on the back side of the swell to prevent the dinghy from ramming the transom of the yacht. Inflatables are inconvenient to tow and take extra time to inflate but are very compact and fit easily into place while at sea. Space can also be saved by using

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456-416: A strong ring on the bow. The ring secures the painter (the line that anchors the boat to a dock), and is used for towing and anchoring. Ideally, the dinghy should also have two other rings (one on each side of the stern transom) which, with the bow ring, are used for lifting and securing the dinghy for stowage. The only other essential pieces of hardware are rowlocks (also known as oarlocks). Conventionally,

494-537: A wave. Both rudders and lee boards have swiveling tips so the dinghy can be landed. Rudders are often arranged so the tiller folds against the rudder to make a compact package. Racing dinghies usually have a daggerboard or centreboard to better sail upwind. The trunk is in the middle of what would otherwise be cargo area. A self-rescue dinghy intended to be used as a proactive lifeboat has leeboards on either side, to allow for maximum open cockpit area. Solar propulsion uses hybrid flexible solar panels integrated into

532-466: Is a type of small boat , often carried or towed by a larger vessel for use as a tender . Utility dinghies are usually rowboats or have an outboard motor . Some are rigged for sailing but they differ from sailing dinghies , which are designed first and foremost for sailing. A dinghy's main use is for transfers from larger boats, especially when the larger boat cannot dock at a suitably-sized port or marina . The term "dinghy towing" sometimes

570-492: Is important to competitive rowing. Effective rowers learn to lever the boat past the end of the blade, rather than pulling the blade through the water. The World Rowing Federation rulebook defines oars as Class II. Both the Class I and Class II perspectives can be used to calculate the forces on the rower, boat, and water, with equivalent results. The calculations are simpler for the Class I perspective. The mechanical advantage of

608-431: Is limited. Some newer dinghies have much greater buoyancy, giving them more carrying capacity than older boats of the same size. On yachts shorter than 10 m (32 ft 10 in), there is usually not enough room for a reasonably sized dinghy. A dinghy is useful to avoid the need for expensive dock or slip space, so owners of small yachts compromise by carrying a small rigid dinghy or deflated inflatable, or by towing

646-405: Is more efficient and thus preferable for long-range rowing. The oars used for transport come in a variety of sizes. The oars used in small dinghies or rafts can be less than 2 metres long. In classical times warships were propelled by very long oars that might have several oarsmen per oar. These oars could be more than a dozen metres long. According to Callixenus , as cited by Athenaeus , in

684-428: Is not presented at the end of the race as a more familiar precious metal cup might be, but rather given by the club, school or university that the winning crew or rower represented. A trophy oar is a competition oar that has been painted in the club colours and has then had the details of the race signwritten on the face of the blade. The most common format has the coat of arms or crest of the club or school positioned in

722-485: Is used to refer to the practice of towing a car or other smaller vehicle behind a motorhome , by analogy to towing a dinghy behind a yacht . The term is a loanword from the Bengali ḍiṅgi , Urdu ḍīngī , and Hindi ḍieṁgī . The term "dinghy" has some variability in its definition, but is generally a small open boat which may be powered by oars, sail or an outboard motor. Some individual examples have

760-498: The carvel or clinker methods. Favoured woods, in order of rot-resistance, are white oak, black locust , species of cedar and pine , true as well as African and Asian mahoganies , fir and spruce . Rot resistance depends on paint as well as protection from rainwater. Plastic hardware is sometimes used, but bronze and stainless steel are good corrosion -resistant materials for hardware, although stainless steel can be subject to crevice corrosion after many years especially in

798-442: The balance point is about 12 inches outboard of the rowlock. Often surplus wood is removed from the blade's width and thickness and at the neck between the blade and the shaft to further reduce outboard weight. As the rower is expending less energy accelerating the (now-reduced) mass of the oar back-and-forth, and will experience less fatigue constantly exerting downward force on the handle (vs. an unbalanced version) -- this type of oar

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836-496: The centre, with the crew names and the race details arranged around this. Many older universities ( Oxford and Cambridge for example, as well as Yale and Harvard) and their colleges have long histories of using the trophy oar and many examples are on display in club houses around the world. In Norway , both Fedje Municipality and Herøy Municipality both have oars in their coat of arms . Oars have been used to describe various animals with characteristics that closely resemble

874-400: The coachroof where there is the most space. It is useful for a dinghy carried this way to have handholds built into the bottom, making launching easier and providing handholds on deck. Most yachts launch their dinghies by hand or with a simple lifting tackle rigged from the main mast. Davits over the transom is convenient and elegant, but sailing in a heavy following sea could cause the loss of

912-513: The gel coat. Inflatable dinghies can be made of fabrics coated with Hypalon , neoprene or PVC . Rigid dinghies can be made of glass-fibre reinforced plastic (GRP) but injection-moulded one-piece hulls are also available. Other materials for modern rigid dinghies include aluminium , marine plywood which tends to be much lighter than most types and, with the advent of sturdy, UV resistant polyurethane varnishes, wood. Some wooden dinghies (especially of classic or historical form) are built using

950-405: The great ship of Ptolemy the oars of the upper tier were over 50 feet (15 m) in length with handles leaded so as to equalize the weight inboard and outboard. The oars used in competitive rowing are long (250–300 cm) poles with one flat end about 50 cm long and 25 cm wide, called the blade. The part of the oar the oarsman holds while rowing is called the handle . While rowing,

988-580: The inside of the transom. Small dinghies under 3.66 m (12 ft) are usually powered by rowing with one set of oars . Beyond 4.88 m (16 ft) it is feasible to have two or even three rowers, normally using a pair of oars. In some models, sliding thwarts allow far more powerful rowing while in others, a removable thwart can permit standing rowing. Some self-rescue dinghy/yacht tender dinghies have two sets of oarlocks (rowlocks) and an adjustable middle seat to allow for ergonomically efficient rowing positions. A single sculling oar with an oarlock on

1026-404: The mast), and usable with or without a boom. Traditional working dinghies have a lee board that can be hooked over the side. This does not split the cargo space. A sailing rudder is usually tied or clipped to a simple pair of pintles (hinge pins) on the transom with the bottom pintle being longer so that the rudder can be mounted one pintle at a time. The rope keeps the rudder from floating off in

1064-409: The oar depends on the length of the oar from the oarlock to the blade, compared to the length from the oarlock to the rower's hand(s). The further away from the oarlock the blade is, the more difficult it is to row and the more distance each stroke will move. This is a normal, usually wooden oar to which weight has been added at the inboard end so that the blade end is noticeably lighter and easier for

1102-407: The oar slipping past the rowlock. Oars usually have a handle about 150mm long, which may be a material sleeve or alternatively an ovoid shape carved to fit the hands. Oars are levers . Which class of lever depends on the frame of reference . From the rower's perspective, the oar can be seen as a Class I lever. The oar is fixed in the oarlock, the rower pulls on the handle, and the blade moves in

1140-407: The oars are supported by metal frames attached to the side of the boat called riggers, while the oar fits into the oarlocks at the ends of each rigger. Classic oars were made of wood , but modern oars are made from synthetic material, the most common being carbon fibre . The sport of competitive rowing has developed a tradition of using an oar as a memento of significant race wins. A 'trophy oar'

1178-420: The opposite direction to propel the boat. The blade is further from the oarlock than the rower's hands. So, the heavy force of a short rowing motion becomes a smaller force over a greater distance. From an observer on the shore, the oar is instead a Class II lever. Here, the fulcrum is the blade , planted in the water. The rower pulls on the handle and the boat moves along with them. The "Class II" perspective

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1216-500: The option of being powered by all three of these methods, some by two, and some by just one means of propulsion. A dinghy does not have a cabin or a fixed keel. The upper size limit is often stated as 20 feet (6.1 m) length. Particularly small examples are 6 feet (1.8 m) long. Dinghies used as ship's boats , particularly in naval use, are often stated as having a size range of 12 to 14 feet (3.7 to 4.3 m) or 12 to 16 feet (3.7 to 4.9 m). Dinghies are designed for

1254-426: The rear transom can be a compact emergency oar. Inflatable dinghies without a rigid bottom are difficult to row more than a short distance, and are usually powered with an outboard motor , or, if necessary, paddled. Another option is an outboard motor. Two horsepower per meter can reach hull speed. Ten horsepower per metre (7.5 kW/m) will put a flat-bottomed dinghy on plane . A 3.05-metre (10 ft) dinghy with

1292-515: The said rowing implement. The members of the Family Regalecidae , elongated deep-sea fishes, are called oarfish because their body shape is similar to that of an oar. The hawksbill turtle 's genus of Eretmochelys is derived from the Greek root eretmo , which roughly translates to oar . The turtle was so-named because of the oar-like shape of its front flippers . Dinghy A dinghy

1330-414: The short end of the oar, while the long end is in the water. By contrast, paddles are held in both hands by the paddler, and are not attached to the vessel. Rowers generally face the stern of the vessel, reach towards the stern, and insert the blade of their oar in the water. As they lean back, towards the vessel's bow , the blade of their oars pivots in the oarlock, and the end in the water moves towards

1368-468: The stern, providing forward thrust . For thousands of years vessels were powered either by sails , or by the mechanical work of rowers, or by paddlers. It is common for an oar propelled vessel to also have the option to be powered by sail, both in antiquity (for instance the galley ) and more recently. Rowing oars have been used since the early Neolithic period . Wooden oars, with canoe-shaped pottery, dating from 5000–4500 BC have been discovered in

1406-534: The storage problems for tenders for yachts, though a fast inflatable boat powered by a powerful outboard motor would not be considered a dinghy. The inflatable life rafts which equipped British military aircraft during World War 2 (and for a period before and after) were called dinghies. Dinghies usually range in length from about 1.8 to 6.1 m (6 to 20 ft). Larger auxiliary vessels are generally called tenders , pinnaces or lifeboats . Folding and take-down multi-piece (nesting) dinghies are used where space

1444-406: The transom and flooding the boat. A typical sail choice for a dinghy is gunter rig with a shorter mast that fits within the hull when unstepped. Sprit rigs have no boom, and the advantage that the sail can be brailed up out of the way against the mast when rowing or motoring. Lug rigs are another common single sail type used in small dinghies, both standing and balanced (with some area forward of

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