Definitions, 3rd officer
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//-->Definitions, terminology andshipboard phrases relevantto the topic of ship handlingand this textAdvanceDescribed by that distance a vessel will continue to travel ahead on heroriginal course while engaged in a turning manoeuvre. It is measured from thatpoint at which the rudder is placed hard over, to when the vessel arrives on a newcourse 90° from the original.Air DraughtThat measurement from the waterline to the highest point of the ves-sel above the waterline.AnchorageA geographic area suitable for ships to lay at anchor. Ideally, it would havegood holding ground and be free of strong currents and sheltered from the prevailingweather. It is usually identified on the nautical chart by a small blue anchor symbol.Anchor AweighAn expression used to describe when the vessel breaks the groundand no longer secures the vessel. The cable is in the up/down position and the ves-sel is no longer attached to the shore by the anchor.Anchor BallA round ball shape, black in colour, which is required to be shown byvessels at anchor, under the Regulations for the Prevention of Collision at Sea.Anchor BearingsThose bearings taken to ascertain the ship’s position when shehas become an anchored vessel.Anchor BuoyAn identification buoy used to denote the position of the deployedanchor. It is hardly ever used by commercial shipping in this day and age.Anchor Coming HomeThe action of drawing the anchor towards the ship asopposed to pulling the ship towards the anchor.Anchor PlanA preparatory plan made by the Master and ship’s officers prior totaking the ship to an anchorage.Anchor WarpA steel wire hawser length, usually attached to a short length ofanchor chain or directly onto the anchor for warping the vessel ahead or astern.xxixxiiDEFINITIONS, TERMINOLOGY AND SHIPBOARD PHRASESAstern(i) The movement of the ship’s engines in reverse, to cause the stern firstmovement of the vessel; (ii) Descriptive term used to describe an area abaft theship’s beam and outside of the vessel’s hull.Auto-PilotA navigation bridge control unit employed to steer the vessel in anunmanned mode. Various controls can be input by the operator to compensate forsea and weather conditions but the unit is effectively a free-standing steering unit.AziPodTrade name for a rotable thruster unit with or without ducting, turningthrough 360° rotation and providing propeller thrust in any direction.Baltic MoorA combination mooring of a vessel alongside the berth which employsa stern mooring shackled to the offshore anchor cable in the region of the ‘gangerlength’. When approaching the berth, the offshore anchor is deployed and theweight on the cable and the stern mooring act to hold the vessel just off the quay.Band BrakeA common type of brake system found employed on windlasses. Theband brake is a screw on friction brake, designed to check and hold the cable lifter(gypsy) when veering anchor cable.BeachingThe term used to describe the act of the ship taking the ground inten-tionally. It is a considered action if the ship is damaged and in danger of being lost.BightThe middle part of a line or mooring. It may be seen as a loop in a rope ormay be deliberately created to run around a bollard providing two parts of a moor-ing (instead of one). It is considered extremely dangerous to stand in the bight of arope and persons in charge of mooring decks should watch out for the young or lessexperienced seafarers, when working with rope bights.Bitter EndThat bare end of the anchor cable which is secured on a quick releasesystem at the cable locker position.BittsA seaman’s term for describing the ship’s bollards.Bollard PullAn expression which is used in charter parties to grade the capacityof a tug and its efficiency. The bollard pull is assessed by measurement, against thepulling capacity of a tug, as measured by a dynamometer. The thrust, or forcedeveloped is known as ‘Bollard Pull’ and is expressed in tonnes. It is useful for marinepilots to assess the wind force affecting the ship against the available ‘bollard pull’.Bow AnchorA vessel is normally fitted out with two working bow anchors.Specialist vessels may also be equipped with additional anchors for specific trade oroperations, i.e. stern anchor.Bow StopperA collective name to describe either a guillotine or a compressor.Both of which act as an anchor cable stopper. It is one of the securing devicesDEFINITIONS, TERMINOLOGY AND SHIPBOARD PHRASESxxiiiapplied to the anchor cable when the vessel is at sea. Alternatives: the AKD stopper(Auto Kick Down).BreakersThese are waves which break against the shoreline producing surf.Breast LineA ship’s mooring line which is stretched at right angles to the fore andaft line of the vessel. By necessity, they are generally short compared to the long driftof head or stern lines, the function of the breast line being to retain the vessel along-side the quay.Brought UpAn expression used to describe when the vessel is ‘Brought Up’ to theanchor, when the anchor is deployed and holding. The scope of cable is observed torise and fall back in a catenary indicating that the vessel is riding to her anchor andnot dragging her anchor.Bruce AnchorA trade name to describe a specialist anchor manufactured by theanchor company ‘Bruce Ltd’. The original ‘Bruce’ design incorporated the hook effectof the Admiralty Pattern Anchor and the Spade effect of the stockless anchor to pro-duce a high holding power anchor with no moving parts.BullringOften referred to as a centre lead, set well forward in the eyes of the ves-sel. It is often employed for towing or accommodating buoy mooring lines. Whennot employed with moorings it is often used to hold a company or ship’s emblem.CableA nautical measurement equivalent to one tenth of a nautical mile, or 100fathoms (also 608 feet).Cable HolderA cable lifter which is mounted horizontally as opposed to verti-cally on a windlass axle. Some passenger and warship vessels operate anchors withcable holders rather than windlass operations.CaissonThe term used to describe a dry dock or dock gate system.CapstanA vertically mounted warping drum with its motor secured below decks.The sides of the drum are fitted with ‘whelps’ to provide improved holding formooring rope turns.Carry UpA term used to refer to moorings being carried up the quayside whenmooring alongside or entering a dock, the moorings usually then being employed towarp the vessel ahead or astern or assist in the manoeuvring of the vessel.CavitationA physical phenomena experienced in the region of a rotating pro-peller and its supporting structure. The cause is generally an air bubble flow whichis non-uniform, associated with the water flow from the propeller action. Extensivecavitation effect can give rise to excessive corrosion in the propeller area of thevessel.xxivDEFINITIONS, TERMINOLOGY AND SHIPBOARD PHRASESChart DatumA plane of reference for charted depths. The United Kingdom employsthe lowest astronomical tide, the lowest water prediction. In the United States, it is themean low water.Circle of SwingThat area that a vessel will swing over when lying to an anchor.The circle of swing can be reduced by mooring to two anchors.Coir SpringsHeavy duty harbour moorings manufactured in coir rope. They aredesigned to be picked up by a vessel mooring in a harbour, usually where heavyswells are experienced. Commonly referred to as ‘storm moorings’. Common toports on the Pacific rim, they are used in addition to the ship’s own moorings.Composite TowlineA towline which is established by employing the ship’sanchor cable secured to the towing vessel’s towing spring.Con (Conn)An expression used to describe the person who has the control of thenavigation of the vessel.Contra-rotating PropellersTwo propellers mounted on the same shaft rotating inopposite directions to balance torque.Controllable Pitch PropellerA propeller which is constructed in such a mannerthat the angle of the blades can be altered to give a variable pitch angle. Namelyfrom zero pitch to maximum pitch ahead or astern.Crest of a Wavewave.The peak or highest point of a wave. Opposite to the trough of aCrossA term used to describe a ‘foul hawse’ where the anchor cables have crossedover as the vessel has swung through 180°.Devils Clawat sea.A securing device used to secure the anchor cable, when the vessel isDocking WinchThe name given to the aft mooring deck winch which is employedfor use with the stern mooring lines. It may also have an integrated cable liftingoperation if the vessel is equipped with a stern anchor.Double-upWhen referred to moorings, means the act of doubling a single partmooring to a double mooring, e.g. double up the forward spring line.DragAn effect which opposes the ship’s forward motion and can be caused byshell/hull friction, rudder action or appendages extending from the hull, effectivelyreducing the ship’s speed. The term is also used to describe a ship dragging its anchor.Dragging AnchorAn expression used to describe a vessel which is moving overthe ground when its anchor is not dug in and holding.DEFINITIONS, TERMINOLOGY AND SHIPBOARD PHRASESxxvDraughtThe depth measure of a freely floating ship. It is the vertical measure-ment between the keel of the ship to the waterline (alternative spelling ‘draft’).Drawing the Anchor HomeA phrase which describes pulling the anchor hometowards the ship as opposed to pulling the ship towards the anchor.Dredging (an anchor)A term when used in conjunction with an anchor, it means thedeliberate dragging of an anchor when at short stay, over the ground of the sea bed.Drop an Anchor UnderfootThe action of letting go a second anchor at short stay.It is usually done to reduce the ‘Yaw’ or movement by the ship about the ridingcable. It tends to act as a steadying influence to oscillations by the ship when at a sin-gle anchor.DuctingA term used to describe the propeller being encompassed by a partialsteel tunnel to ‘chunnel’ the water flow more directly onto the propeller blades.Ebb TideThe tidal flow of water out of a port or harbour away from the land.ElbowA term used to describe a ‘foul hawse’ where both the deployed anchorcables have crossed over and the vessel has turned 360°.Even KeelAn expression which describes a vessel which is without any angle oflist, is said to be on ‘even keel’.FairwayThat navigable and safe area of a harbour approach which may includethe main shipping channel. It is usually marked with a fairway buoy.Falling TideA term used to describe when the tide is falling on the ebb and thedepth of water is decreasing.FenderA purpose-built addition to the ship’s hull to prevent damage to the hullwhen landing alongside a jetty or other hard surface. It may also be a portable devicesuspended on a lanyard to protect the hull from damage when strategically placedbetween the quayside and the ships hull to cushion and protect the ships side.FetchDescribed as the distance that the wind blows over the sea without encoun-tering any appreciable interference from land masses. The term was also previouslyused in sailing vessels, i.e. to ‘fetch up on a starboard tack’.Final DiameterIs defined as that internal diameter of the ships turning circlewhere no allowance has been made for the decreasing curvature as experiencedwith the tactical diameter.FineA bearing reference which indicates an observation bearing, less than1⁄2com-pass point off the bow, but not dead ahead. [ Pobierz całość w formacie PDF ] |