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417 Cards in this Set

  • Front
  • Back
ABAFT
TOWARD THE STEM OF THE SHIP, BACK, BEHIND
ABOARD
ON OR IN A SHIP
ABRASION
WHEN APPLIED TO A WIRE ROPE: SURFACE LOSS OF METAL ON THE INDIVIDUAL WIRES OF A WIRE ROPE
ABREAST
SIDE BY SIDE
ACCOMMODATION LADDER
"ACCOM LADDER" STAIRS SLUNG AT THE GANGWAY, LEADING DOWN TO THE VESSELS SIDE TO A POINT NEAR THE WATER, FOR SHIP ACCESS FROM SMALL BOATS
ACID
ANY CORROSIVE HAVING A PH LESS THAN 7
AFT
NEAR THE STEM; TOWARD THE STEM
AFTER BODY
THE PORTION OF THE SHIP'S BODY AFT OF THE MID SHIP SECTION
AFTER FRAMES
FRAMES AFT OF A MIDSHIPS
AFTER PEAK
THE AFTERMOST TANK OR COMPARTMENT FORWARD OF THE STEM POST
AFTER PERPENDICULAR
A VERTICAL LINE AT OR NEAR THE STEM OF THE SHIP
ALOFT
IN THE UPPER RIGGING; ABOVE THE DECKS
ALONGSIDE
DENOTES THAT 2 SHIPS ARE ALONG SIDE EACHOTHER "UNREP"
AMIDSHIPS
IN THE VICINITY OF THE MIDDLE PORTION OF A VESSEL AS DISTINGUISHED FROM HER ENDS
ANCHOR
A HEAVY IRON OR STEEL IMPLEMENT ATTACHED TO A VESSEL BY MEANS OF A ROPE OR CHAIN CABLE FOR HOLDING THE VESSEL AT REST IN THE WATER
ANCHOR, BOWER
THE LARGE ANCHORS CARRIED IN THE BOW OF A VESSEL
Anchor, kedge
A small anchor used for warping or kedging. It is usually planted from a small
boat - the vessel being hauled up toward it. The weight varies - usually from 900 to 1,200 pounds.
Anchor, sea
This is not a true anchor as it does not sink to the bottom. It is a conical-shaped canvas
bag required by the Bureau of Marine Inspection to be carried in each lifeboat. When placed
overboard it serves a double purpose in keeping the boat head-on into the sea and in spreading a
vegetable or animal oil from a container placed inside the bag. It is sometimes called an oil
spreader.
Anchor hawk
Grappling device used to recover lost anchors, chains, wire rope, etc.
Anchor windlass
The machine used to hoist and lower anchors
Ancillary equipment
Equipment that supports the operation of a system’s principal components
or assemblies
Angle bar
A bar of angle-shaped section used as a stiffener and for attachment of one plate or
shape to another.
Angle collar
A collar or band made of one or more pieces of angle bar fitted tightly around a
pipe, trunk, frame, longitudinal, or stiffener, intersecting or projecting through a bulkhead or deck
for the purpose of making a watertight or oiltight joint
Appendages
Relatively small portions of a vessel extending beyond its main outline as shown
by transverse and waterplane sections, including: shafting, struts, bossings, docking and bilge
keels, propellers, rudder, and any other feature extraneous to the hull and generally immersed
Appendage drag
The hydrodynamic force created by the resistance of underwater appendages
such as rudders, skegs, struts, propellers,
Area of sections
The area of any cross-section of the immersed portion of a vessel, the crosssection
being taken at right angles to the fore-and-aft centerline of the vessel.
Assembly
The parts to be fitted together to make a whole system or system component
Astern
Signifying position, in the rear of or abaft the stem; as regards motion, the opposite of
going ahead; backwards
Athwart
Lying at right angles to the fore-and-aft centerline of a ship, sometimes pronounced
“athwartships.”
Athwartship
Reaching across a vessel, from side to side
Automatic-tension towing machine.
Winch-like machine which relieves tension on the towline
by automatically paying out and then reclaiming wire when the tension is reduced
Auxiliaries
Various winches, pumps, motors, engines, etc., required on a ship, as distinguished
from main propulsive machinery (e.g., boilers and engines on a steam installation).
Auxiliary
A vessel that maintains, supplies, or supports combatants
Back stay
Stays which extend from all mast levels, except the lower, to the ship's side at some
distance abaft the mast. They serve as additional supports to prevent the masts from going forward,
and also contribute to lateral support, thereby assisting the shrouds.
Bail
The part of a pelican hook or chain stopper that holds the hook closed.
Ballast
Portable ballast,
usually in the form of water pumped into or out of the bottom, peak, or wing ballast tanks, is
utilized to overcome a temporary defect in stability or trim due to faulty loading, damage, etc.,
and to submerge submarines, and LSD
Ballast tanks
Tanks provided in various parts of a ship for introduction of water ballast; when
necessary, to add weight to produce a change in trim or stability of the ship, and for submerging
submarines
Ballast water
Seawater confined to double-bottom tanks, peak tanks, and other designated compartments
for use in obtaining satisfactory draft, trim, or stability
Ballasted condition
A condition of loading in which it becomes necessary to fill all or part of
the ballast tanks in order to maintain proper immersion, stability, and steering qualities brought
about by consumption of fuel, stores, and water, or lack of part or all of the designed cargo
Barge
A craft of full body, heavy construction, designed for the carriage of cargo but having no
machinery for self-propulsion.
Baseline
A fore-and-aft line passing through the lowest point of the hull
Barrel
The rotating drum of a capstan or winch
Beach gear
A generic term for all equipment meant to be used during the extraction of a
grounded ship.
Beam (B)
The breadth of the ship at the broadest point. Beam is measured in feet.
Beam ends
A vessel hove over or listed until her deck beams approach vertical is said to be “on
her beam ends.”
Beam line
A line showing the points of intersection between the top edge of the beam and the
molded frame line, also called “molded deck line.”
Bearer
A term applied to foundations, particularly those having vertical web plates as principal
members. The vertical web plates of foundations are also called bearers.
Beaufort Scale
A numerical scale (from 0 to 12) used for rating velocity of wind in ascending
velocity.
Between decks
The space between any two decks. Decks need not be adjacent. Frequently
expressed as “tween decks.”
Bight
A loop or bend in a rope; strictly, any part between the two ends may be termed a bight.
Bilge
The rounded portion of a vessel's shell which connects the bottom with the side. To open
a vessel’s lower body to the sea.
Bilge plates
The curved shell plates that fit the bilge.
Bilges
The lowest portion of a ship inside the hull, considering the inner bottom, where fitted, as
the bottom hull limit.
Billboard
An inclined platform, fitted at the intersection of the forward weather deck and the
shell, for stowing an anchor. It may be fitted with a tripping device for dropping the anchor overboard
Bird-caging
The phenomenon of wires flaring out around the full diameter of wire rope, with
resulting kinks in the wires. This can occur when there is a sudden release of a heavy load on a
wire rope.
Bitter end
The inboard end of a vessel's anchor chain which is made fast in the chain locker; the
free end of a fiber or wire rope.
Bitts
A term applied to short metal or wood columns extending up from a base plate secured to a
deck or bulwark rail or placed on a pier for the purpose of securing and belaying ropes, hawsers,
cables, etc.
Block, snatch
A single-sheave block having one side of the frame hinged so that it can be
opened to allow the bight of a rope to be placed on the sheave, thus avoiding the necessity of
threading the end of the rope through the swallow of the block. Usually employed as a fairlead
around obstructions.
Body plan
A plan consisting of two half-transverse elevations, or end views, of a ship having a
common vertical centerline, so that the right-hand side represents the ship as seen from ahead, and
the left-hand side from astern. On the body plan appear the forms of the various cross sections,
the curvature of the deck lines at the side, and the straight-line projections of the water, bow, buttock,
and diagonal lines.
Bollard
A single cast-steel post secured to a wharf or pier and used for mooring vessels by
means of lines extending from the vessel.
Bollard pull
The maximum pulling power of a ship at a given power rating with no way on.
Bonjean curves
Curves of areas of transverse sections of a ship. The curves of the moments of
these areas above the baseline are sometimes included.
Boom
A term applied to a spar used in handling cargo, or to which the lower edge of a fore-andaft
sail is attached.
Boom lines
The wire ropes supporting the boom or jib on cranes and vangs
Boot topping
An outside area on a vessel’s hull from bow to stem between certain waterlines to
which special air-, water-, and grease-resisting paint is applied; also, the paint applied to such
areas.
Bottom
That portion of a vessel's shell between the keel and the lower turn of the bilge
Bottom, outer
A term applied to the bottom shell plating in a double-bottom ship
Bottom plating
That part of the shell plating which is below the waterline. More specifically, the
immersed shell plating from bilge to bilge.
Bow
The forwardend of the ship. The sides of the vessel at and for some distance abaft the stem,
designated as the right-hand or starboard bow, and the left-hand, or port bow.
Bow thruster
A transversely-mounted propeller or other thrusting device located near the bow
and used to control lateral movement.
Breadth, extreme
The maximum breadth measured over plating or planking, including beading
or fenders.
Breaking strength
The actual or ultimate rated load required to pull a wire, strand, or rope to
destruction. As an aggregate value, the sum of individual breaking loads of all wires in a strand or
rope.
Breakwater
A term applied to plates or timbers fitted on a forward weather deck to form a Vshaped
shield against water shipping over the bow.
Breast line.
A mooring line from ship to pier, or ship to ship, perpendicular to the fore-and-aft
axis, or at right angles to the ship.
Bridle
A two-legged towing rig of wire or chain attached to towing pads or a set of bitts on the
tow. At the apex is a flounder plate or ring, dependent upon whether a chain bridle is being used.
The two legs and the imaginary line between the points of attachment should form an equilateral
triangle
Bridle rig
The rigging of a tow with two legs from the tow's bow to a flounder plate.
Buckle
A distortion, such as a bulge; to become distorted; to bend out of its own plane
Bulkhead
A term applied to any one of the partition walls which subdivide the interior of a ship
into compartments or rooms.
Bulkhead, collision
The foremost transverse watertight bulkhead in a ship, which extends from
the bottom of the hold to the freeboard deck. It is designed to limit flooding in case of collision
damage. Usually, this is the forepeak bulkhead at the after end of the forepeak tank
Bulkhead, swash
A strongly built, non-tight bulkhead placed in oil or water tanks to slow down
the motion of the fluid induced by the motion of the ship.
“Bull rope”
Colloquial term referring to a towline, or to the largest, strongest rope carried on
board.
Bullnose
A closed chock at the bow of a vessel.
Bulwark
The section of a ship's side continued above the main deck that serves as a protection
against heavy weather.
Buoyancy
Ability to float
Buoyancy, reserve.
The floating or buoyant power of the unsubmerged portion of the hull of a
vessel. Usually refers to a specific condition of loading.
BUSHIPS
Bureau of Ships, now Naval Sea Systems Command
Buttock lines
The curves shown by taking vertical longitudinal sections of the after part of a
ship's hull parallel to the ship’s keel. Similar curves in forward part of hull are “bow lines.”
Cable grip.
A termination which is wrapped about the end of a wire rope using interlocking helical
strands, designed so that tensile loads are resisted by induced radial pressures.
Cable-laid
Threeropes laid up like strands from right-to-left. The ropes which serve as strands
are laid upfrom left to right, (e.g., non-rotating wire).
Calculated risk
Accepting an operation or decision based on less than satisfactory conditions,
information or assets
Cant
A term signifying an inclination of an object away from the perpendicular; to turn anything
so that it does not stand perpendicularly or square in relation to a given object
Caprail
Rail on the stem of a towing vessel over which the sweep of the tow wire rides.
Capstan
A revolving device with a, vertical axis used for heaving in mooring lines
Cargo
Merchandise or goods accepted for transportation by ship.
Cargo boom
A heavy boom used in loading cargo.
Carpenter stopper
A mechanical device consisting of a cover that encloses a sliding wedge
within the body that can be opened by knocking away a latch that holds them closed. Used for
stopping off wire rope.
Catenary
The downward curve or sag of a rope suspended between two points.
Center of Buoyancy
The geometric center of gravity of the immersed volume of the displacement
or of the displaced water, determined solely by the shape of the underwater body of the ship.
It is calculated for both the longitudinal location, forward or aft of the middle perpendicular, and
the vertical location above the baseline or below the designed waterline.
Center of Flotation
The geometric center of gravity of the water plane at which the vessel
floats, forward or aft of the middle perpendicular. It is that point about which a vessel rotates longitudinally
when actuated by an external force without change in displacement.
Center of Gravity
The point in a ship where the sum of all moments of weight is zero; the point
at which the combined weight of all the individual components of the vessel’s total weight may be
considered as concentrated; generally located longitudinally forward or aft of the middle perpendicular
and vertically above bottom of keel or below a stated waterline
Centerline
A vertical plane passing fore and aft down the center of a ship; the middle line of the
ship from stem to stem as shown in any waterline view.
Chafing pendant
A length of chain used to reduce chafing or wearing.
Chain
A connected, flexible series of links, usually of metal, used for binding, connecting, or
other purposes.
Chain bridle.
A chain used in a bridle rig or a single pendant rig.
Chain locker
Compartment in forward lower portion of ship in which anchor chain is stowed.
Chain pendant.
BUSHIPS
Bureau of Ships, now Naval Sea Systems Command
Buttock lines
The curves shown by taking vertical longitudinal sections of the after part of a
ship's hull parallel to the ship’s keel. Similar curves in forward part of hull are “bow lines.”
Cable grip.
A termination which is wrapped about the end of a wire rope using interlocking helical
strands, designed so that tensile loads are resisted by induced radial pressures.
Cable-laid
Threeropes laid up like strands from right-to-left. The ropes which serve as strands
are laid upfrom left to right, (e.g., non-rotating wire).
Calculated risk
Accepting an operation or decision based on less than satisfactory conditions,
information or assets
Cant
A term signifying an inclination of an object away from the perpendicular; to turn anything
so that it does not stand perpendicularly or square in relation to a given object
Caprail
Rail on the stem of a towing vessel over which the sweep of the tow wire rides.
Capstan
A revolving device with a, vertical axis used for heaving in mooring lines
Cargo
Merchandise or goods accepted for transportation by ship.
Cargo boom
A heavy boom used in loading cargo.
Chain pendant
A piece of chain used as a strap; chain rigged between the tow and tow hawser;
chain used to create a catenary
Chain stopper
A device used to secure chain, thereby relieving the strain on the windlass-, also
used to secure the anchor in the housed position in the hawse pipe.
Check
To keep a strain on a line without parting it.
Chock
A heavy, smooth-surfaced fitting usually located near the edge of the weather deck
through which wire ropes or fiber hawsers may be led
Chute
An inclined or vertical trough or passage, down which something may be slid or passed.
Clamp
A metal fitting used to grip and hold wire ropes. Two or more may be used to connect
two ropes in lieu of a short splice or in turning in an eye.
Cleats
Pieces of wood or metal, of various shapes according to their uses, usually having two
projecting arms or horns upon which to belay ropes.
Clinometer
An instrument used for indicating the angle of roll or pitch of a vessel.
Closed socket
A wire rope termination similar to a padeye or ring.
Coaming, hatch
A frame bounding a hatch for the purpose of stiffening the edges of the opening
and forming the support for the covers. In a steel ship, it generally consists of a strake of
strong vertical plating completely bounding the edges of a deck opening.
Cofferdams
Empty spaces separating two or more compartments for the purpose of insulation,
or to, prevent the liquid contents of one compartment from entering another in the event of the
failure of the walls of one to retain their tightness
COLREGS
U.S. Coast Guard rules of the road
Control, lateral.
The power to direct or regulate sideways movement
Cordage
A comprehensive term for all ropes, of whatever size or kind, on board a ship.
Core (line)
The axial member of a wire rope about which the strands are laid. It may consist of
wire strand, wire rope, synthetic or natural fiber, or solid plastic.
Counter
The part of a ship’s stem which overhangs the stern post, usually that part above the
waterline.
Crabbing
Moving sideways through the water.
Crane
A machine used for hoisting and moving pieces of material and portions of structures or
machines that are too heavy to be handled by hand or cannot be handled economically by hand.
Cutwater
The stem of a ship; the forward-most portion of the bow which cuts the water as the
ship moves.
Dead rise.
The amount which the straight portion of the bottom of the floor of the midships section
rises above the baseline in the half-beam of the vessel. Usually expressed in inches.
Deadweight
The difference between the light displacement and the full load displacement of a
vessel; the total weight of cargo, fuel, water, stores, and passengers and crew, and their effects,
that a ship can carry when at her maximum allowable draft.
Deck
The floor of a compartment. The deck space exposed to weather where towing and beach
gear operations take place.
Deckhouse
A term applied to a partial superstructure that does not extend from side to side of a
vessel, as do the bridge, poop, and forecastle.
Deck machinery
A term applied to capstans, windlasses, winches, and miscellaneous machinery
located on the deck of the ship.
Deck plating
A term applied to the steel plating of a deck.
Deck stringer
The strip of deck plating that runs along the outer edge of a deck.
Deep floors
A term applied to the floors at the ends of a ship which are deeper than the standard
depth of floor at amidships.
Deep tanks
Tanks extending from the bottom or inner-bottom of a vessel up to or higher than
the lowest deck. They are fitted with hatches so that they also may be used for cargo.
Depth (D)
The distance between the baseline and the uppermost watertight deck. Depth is measured
in feet.
Depth, molded
The vertical distance from the molded baseline to the top of the uppermost
strength deck beam at side, measured at midlength of the vessel.
Deshackling kit (Detachable-Link Tool Kit)
A tool set used to assemble and disassemble
detachable links. Tools included in these sets are hammers, punches, lead pellets, spare taper
pins, and hair pins.
Detachable link
A joining link or chain link used to connect chain to anchors, chain, or other
pieces of mooring, towing, or beach gear equipment.
Di-lok chain
Integral stud-link chain formed by forging.
“Dipped” shackle, padeye
The placement of a shackle through a padeye or connection, as
opposed to passing the mortise over the padeye. The padeye is shaped to accept a shackle as
described.
Displacement (W)
The displacement is the weight of the ship and all cargo on board and is measured
in weight units, usually in long tons of 2,240 pounds. Displacement is directly related to
displacement volume and is normally obtained by dividing the displacement volume by 35, the
number of cubic feet of salt water in a long ton.
Displacement curves
Curves drawn to give the displacement of the vessel at varying drafts.
Usually, these curves are drawn to show the displacement in either salt or fresh water, or in both.
Displacement volume (V)
The displacement volume is the total volume of the underwater hull.
Displacement volume is measured in cubic feet.
Displacement, designed
The displacement of a vessel when floating at her designed draft.
Displacement, full load
The displacement of a vessel when floating at her greatest allowable
draft as established by the classification societies
Displacement, light
The displacement of the vessel complete with all items of outfit, equipment,
and machinery on board but excluding all cargo, fuel, water, stores, dunnage, and passengers
and the crew and their effects.
Dog
A pawl; a device applied to a winch drum to prevent rotation. See “On the dog.”
Dolphin
A term applied to several piles that are bound together, situated either at the corner of a
pier or out in the stream and used for docking and warping vessels. Also applied to single piles
and bollards on piers that are used in docking and warping.
Door, watertight
A door so constructed that when closed it will prevent water under pressure
from passing through.
Double-bottom
A term applied to the space between the inner and outer skins of a vessel called
respectively the “inner-bottom” and “shell,” usually extending from bilge to bilge for nearly the
whole length of the vessel, subdivided into watertight or oiltight compartments.
Doubling plate
An extra plate secured to the original plating to provide additional strength or to
compensate for an opening in the structure.
Draft (T)
The vertical distance between the waterline and the deepest part of the ship at any
point along the length. Draft is measured in feet. Drafts are usually measured at the forward
(draft forward, Tf) and the after perpendiculars (draft aft, Ta). The mean draft (Tm), frequently
used id salvage calculations, is the average of the forward and after drafts. The draft is assumed to
be the mean draft if the point at which the draft is taken is not specified. The navigational draft of
a ship accounts for sonar domes, pit swords, and other underwater appendages. The navigational
draft is never used for salvage calculations.
Draft marks
The numbers which are placed on each side of a vessel near the bow and stem, and
often also amidships, to indicate the distance from the number to the bottom of the keel or a fixed
reference point. These numbers are six inches high, are spaced twelve inches bottom to bottom
vertically, and are located as close to the bow and stem as possible.
Drag
Forces opposing direction of motion due to friction, profile, and other components; the
designed excess of draft aft measured from the designer's waterline. The drag is constant and
should not be confused with trim.
Drogue
A device used to slow the rate of movement
Dunnage
Any material, such as blocks, boards, paper, burlap, etc., necessary for the safe stowage
of stores and cargo.
Dynamic load.
Relating to energy or physical force in motion; as opposed to static load, a force
producing motion or change.
Elongation
Stretching of chain or other tension member caused by an excessive load.
Equilibrium, neutral
The state of equilibrium in which a vessel inclined from its original position
of rest by an external force tends to maintain the inclined position assumed after that force
has ceased to act.
Equilibrium, stable
The state of equilibrium in which a vessel inclined from its original position
of rest by an external force tends to return to its original position after that force has ceased to
act.
Equilibrium, unstable
The state of equilibrium in which a vessel inclined from its original position
of rest by an external force tends to depart farther from the inclined position assumed after
that force has ceased to act.
Even keel
When a ship rides on an even keel, its plane of flotation is either coincident with or
parallel to the designed waterline.
Eye splice
A loop formed in the end of a rope by tucking the strand ends under or around the
strands of the line part of the rope. A thimble is often used in the loop.
Fairlead
Fittings which lead lines in the direction desired
Fairlead chock
A chock with a roller(s) installed to lead a line to a bitt or cleat.
Fairleader
A fitting or device used to preserve or to change the direction of a rope, chain, or
wire so that it will be delivered fairly, or on a straight lead, to a sheave or drum without the introduction
of extensive friction. Fairleaders, or fairleads, are fixtures, as distinguished from temporary
block rigs.
Fake (Faked down)
To lay out a line in long, flat bights in such form that when needed, it will
pay out freely.
Fall
The entire length of rope used in a tackle. The end secured to the block is called the standing
part; the opposite end, the hauling part.
Failing off
Drifting away from a desired position or direction.
Fathom
A nautical unit of length used in measuring cordage, chains, depths, etc. The length
varies in different countries, being six feet in the United States and Great Britain.
Fatigue
The tendency for materials or devices to break under repeated (cyclic) loading.
Fender
The term applied to various devices fastened to or hung over the sides of a vessel to prevent
rubbing or chafing against other vessels or piers.
Fish Hooks
Outer wires of wire rope that break and cause short ends to project from the rope; a
sign of wire rope deterioration.
Flare
The spreading out from the central vertical plane of the body of a ship with increasing
rapidity as the section rises from the waterline to the rail. Also a night distress signal.
Floor
A plate used vertically in the bottom of a ship running athwartship from bilge to bilge,
usually on every frame to deepen it. In wood ships, the lowest frame timber or the one crossing
the keel is called the floor.
Flounder plate
A triangular steel plate to which chain bridle legs are connected, sometimes
called “fish plate.”
Flukes
The palms, or broad holding portions, at the arm extremities of an anchor, which penetrate
the ground.
Fore
A term used in indicating portions or that part of a ship at or adjacent to the bow. Also
applied to that portion and parts of the ship lying between the midship section and stem; as, forebody,
forehold, and foremast.
Fore and Aft
Lengthwise of a ship.
Forefoot
The lower end of a vessel's stem which is stepped on the keel.
Forward
In the direction of the stem.
Forward perpendicular (FP)
A vertical line through the forward extremity of the design waterline
- the waterline at which the ship is designed to float; a line perpendicular to the baseline and
intersecting the forward side of the stem at the designed waterline.
Founder
To sink as the result of entrance of water.
Frame
A term generally used to designate one of the transverse ribs that make up the skeleton of
a ship. The frames act as stiffeners, holding the outside plating in shape and maintaining the
transverse form of the ship.
Frame spacing
The fore-and-aft distances between frames, heel to heel.
Freeboard (F)
The distance between the waterline and the uppermost watertight deck at any
location along the ship is freeboard. Freeboard is measured in feet.
Freeing ports
Holes in the lower portion of a bulwark, which allow deck wash to drain off into
the sea. Some freeing ports have swinging gates which allow water to drain off but are automatically
closed by seawater pressure.
Free-spooling
To lengthen scope by releasing the clutch-brake and allowing the towing drum to
rotate as a result of the drag of the tow. The tow motor is stationary
“Freshening the nip”
Paying out or hauling in the line to move the contact point so as to distribute
wear.
Frictional resistance
The force created by an object as it moves through a fluid such as water or
air.
Fuse pendant
A pendant of wire rope or chain specifically designed to fail at a known tension.
May be used to protect the rest of the rigging arrangement.
Gear
A comprehensive term in general use on shipboard signifying the total of all implements,
apparatus, mechanisms, machinery, etc., appertaining to and employed in the performance of any
given operation; as “cleaning gear”, “steering gear”, “anchor gear”, etc.
Gooseneck
A swiveling fitting on the heel or mast end of a boom for connecting the boom to the
mast.
Grapnel
A small, 4-armed anchor used mainly to recover objects in the water; an implement
having from four to six hooks or prongs, usually four, arranged in a circular manner around one
end of a shank having a ring at its other end. Used as an anchor for small boats, for recovering
small articles dropped overboard, to hook on to lines, and for similar purposes. Also known as a
grappling hook.
Ground tackle
A general term for all anchors, cables, ropes, etc., used in the operations of
mooring and unmooring a ship.
Gun tackle
A tackle using two single-sheave blocks.
Gunwale
The upper edge of a boat's side. Pronounced “gun-el”. A term applied to the line
where a weather deck stringer intersects the shell.
Gypsy head
A drum attached to a winch around which a rope is turned for heaving in.
H-bitt
A larger structure mounted on the deck or in a bulkhead that is used to lead or stop off a
tow hawser. A head point used for towing
Half-Breadth Plan
A plan or top view of one-half of a ship divided by the middle vertical plane.
It shows the waterlines, cross-section lines, bow and buttock lines, and diagonal lines of the ship's
form projected on the horizontal base plane of the ship.
Hawse pipe
Heavy castings through which the anchor chain runs from the deck down and forward
through the ship's bow plating.
Hawser
A heavy line or wire rope used in warping, towing, and mooring; any line over 5 inches
in circumference.
Hazardous material (HM)
A naturally occurring or synthesized material that can cause the
deterioration of other materials or be injurious to living things.
Heave-around
To haul in
Heave-in
To haul in
Heave-taut
To haul in until the line has a strain on it.
Heave-to
To stop; to bring the ship to a halt, dead in the water
Heavy lift
A system used to supply part or all of the external lifting force required to salvage a
sunken vessel.
Heel
The convex intersecting point or comer of the web and flange of a bar; the inclination of a
ship to one side, caused by wind or wave action or by shifting weights on board.
Heeling
Listing over.
Helix
The twist or curvature of the individual strands of a wire rope
Hockle
Kinking of one or more strands of twisted fiber line or wires on a wire rope.
Hog (Hogging)
Distortion of a ship's hull which results in the bow and stem being lower than
the midships section; opposite of sagging
Hogging strap
A restraining line executing force on the towline to hold it close against the
caprail and/or closer to the fantail.
Hook
A curved or bent piece of metal, wood, etc., used to catch, hold, or pull something
Horsepower, indicated (IHP)
Engine power calculated from cylinder pressure, not accounting
for the mechanical efficiency of the engine.
Horsepower, shaft (SHP)
The power transmitted through the shaft to the propeller. It is usually
measured aboard the ship as close to the propeller as possible by means of a torsionmeter. The
power actually delivered to the propeller is somewhat less than that measured by the torsionmeter.
Shaft horsepower is usually 90 to 98 percent of BHP.
Horsepower, brake (BHP)
Engine power measured at the engine output coupling. Brake
horsepower is usually 65 to 75 percent of IHP.
Hull
The framework of a vessel, together with all decks, deckhouses, and the inside and outside
plating or planking, but exclusive of masts, yards, rigging, and all outfit or equipment.
“In Irons”
An expression used by shiphandlers to indicate limited control in maneuvering the
ship.
“In Step”
An expression used to indicate that the towing ship and its tow are riding the crests
and troughs of waves simultaneously
Inboard
Toward the center.
Inboard profile
A plan representing a longitudinal section through the center of the ship, showing
deck heights, transverse bulkheads, assignment of space, machinery, etc., located on the center
plane or between the center and the shell on the far side.
Independent Wire Rope Core (IWRC)
The internal strand of a multiple strand wire rope,
made up of wire strands twisted together.
Initial stability
The stability of a vessel in the upright position or at small angles of inclination.
It is measured by the metacentric height.
Inner bottom
A term applied to the inner skin or tank top plating. The plating over the doublebottom.
Intercostal
Occurring between ribs, frames, etc. The term is broadly applied, where two members
of a ship intersect, to the member that is cut.
Keckling
Chafing gear on a cable, consisting of old rope.
Keel
A centerline strength member running fore and aft along the bottom of a ship and often
referred to as the backbone. It is composed either of long bars or timbers scarfed at their ends or
by flat plates connected together by riveting or welding
Keel, bilge
A fin fitted on the bottom of a ship at the turn of the bilge to reduce rolling. It commonly
consists of a plate running fore and aft and attached to the shell plating by angle bars.
Kenter detachable link
A type of connection normally used to join two pieces of studlink or
cast chain
King post
A strong vertical post used to support a derrick boom
Kjellam grips
A lightweight stopper useful for passing a wire rope where there is only low tension
likely to be exerted on the rope
Knot
A unit of speed equaling one nautical mile (6,080.20 feet) an hour
Knuckle
An abrupt change in direction of the plating, frames, keel, deck, or other structure of a
vessel.
Kort nozzle
A nozzle used to enclose the propeller of a ship.
Lagging
A term applied to the insulating material that is fitted on the outside of boilers, piping,
etc.
Lateral control wire.
An auxiliary wire used to move the tow hawser athwartships
Lay
The direction of the twist of strands of a rope.
Lay length
The distance measured parallel to the axis of the rope (or strand) in which a strand
(or wire) makes one complete helical convolution about the core (or center).
Layer
A single thickness, coat, fold, wrap, or stratum.
“Lazy Jacks”
Small lines used to tend and recover the towline when rigging a recovery for a
Liverpool bridle.
Length between perpendiculars (LBP or L)
The horizontal distance between the forward and
after perpendiculars. Length between perpendiculars is measured in feet
Length on design load waterline (LWL)
The length along the centerline at the waterline in the
ship's design loaded condition. Length on design load waterline is measured in feet.
Length overall (LOA)
The extreme length of the ship along the centerline. Length overall is
measured in feet; the length of a ship measured from the foremost point of the stem to the aftermost
part of the stem.
Levelwind
A device used to wind the wire on a drum evenly.
Lightening hole
A hole cut out of any structural member, as in the web, where very little loss of
strength will occur. These holes reduce the weight and in many cases serve as access holes. This
is particularly true in floor plates and longitudinals in double bottoms.
Lighter
A boat used in harbors for transporting merchandise; a full-bodied, heavily built craft,
usually not self-propelled, used in bringing merchandise or cargo alongside or in transferring it
from a vessel.
Limber hole
A hole or slot in a frame or plate for the purpose of preventing water from collecting.
Most frequently found in floor plates just above the frames and near the centerline of the
ship.
Limiting draft marks
Asterisk-shaped marks near the forward, after, and midships draft marks
of warships and certain auxiliaries showing the deepest drafts to which the ship can be loaded and
still retain sufficient reserve buoyancy.
Line
A term frequently applied to a fiber or synthetic rope, especially if it moves or is used to
transmit a force
Lines
The plans of a ship that show its form. From the lines drawn full-size on the mold loft
floor are made templates for the various parts of the hull.
List
The deviation of a vessel from the upright position due to bilging, shifting of cargo, or other
cause.
Liverpool bridle
A method of rigging a tow used to maintain ship control when the large yawing
of the tow can overcome directional stability of the towing vessel; most commonly used in
debeaching a ship.
Load cell
An instrument for measuring tension or torque
Load line
The line 18 inches long and 1 inch wide on each side of the ship at the midships section
which indicates the maximum draft to which the ship may be loaded.
Locking pin
Keeper or device used to hold or maintain a chain stopper, shackle, or other similar
devices in a designated position.
Longitudinals
A term applied to the fore-and-aft frames in the bottom of a ship. These frames
are usually made up from plates and shapes and are sometimes intercostal and sometimes continuou
Magazine
Spaces or compartments devoted to the stowage of ammunition
Main body
The hull proper, without the deckhouses, etc.
Main deck
The principal deck of the hull, usually the highest, extending from stem to stern and
providing strength to the main hul
Manhole
A round or oval hole cut in decks, tanks, boilers, etc., for the purpose of providing
access.
Messenger
A light line used for hauling over a heavier rope or hawser.
Metacentric height (GM)
Distance between the metacenter and the center of gravity of a ship; a
measure of stability.
Metacentric Radius (BM)
Distance between center of buoyancy and metacenter (IWP/V)
Midships section (MS)
The vertical transverse section located at the midpoint between the forward
and after perpendiculars, usually the largest section of the ship in area. Also, applied to adrawing showing the contour of the midship frame, upon which are depicted all the structural
members at that point, with information as to their size and longitudinal extent.
Moment of Inertia
A measurement of a plane surface's resistance to rotation about an axis in
the same plane. The magnitude of moment of inertia depends upon the shape of the surface and
varies with the axis used for rotation. The moment of inertia is measured in the fourth power of a
linear unit such as fees or inches' or a combination of both.
Mortise
The opening of a shackle or detachable link. The inside dimension, measured across
the opening, of a shackle or detachable link.
Nip
A sharp bend in a line or wire.
Norman pin
A steel rod or post that can be raised or lowered, usually mounted toward the stem
of a vessel, to limit the sweep of a hawser across the rear deck to provide safe areas for the crew.
Offset
A term used for the coordinates of a ship's form, deck heights, etc.
Offset shackle
A device used to connect the towline to the towing pendant. One end of the
shackle is the size of the towline thimble, whereas the other end is especially made to accommodate
different sizes of chain pendants or anchor bending shackles.
“On the brake”
Towing with the tow hawser restrained by the brake system of the towing
machine or winch.
“On the dog”
Occurs when a pawl is engaged in the ratchet teeth of the drum of the towing
machine.
Open socket
A wire rope termination that is shaped similarly to a shackle; mates with a closed
socket.
Outboard
Away from the centerline toward the outside; outside the hull.
Outboard profile
A plan showing the longitudinal exterior of the starboard side of a vessel,
together with all deck erections, stacks, masts, yards, rigging, rails, etc.
Padeye
A fitting having one or more eyes integral with a plate or base to provide ample means
of securing and distributing the strain over a wide area. The eyes may be either “worked” or
“shackled.” Also known as lug pads, hoisting pads, etc.
Padeye (horizontal, vertical)
A metal structure with a hole for a shackle or pin to pass a ring.
On a vertical padeye, the axis of the hole is parallel to the deck. On a horizontal padeye, the axis
is perpendicular to the deck. Vertical padeyes are often referred to as freestanding padeyes.
Palm
The flat, inner surface of the fluke of an anchor
Parcelling
Wrapping a line or wire with strips of canvas.
Pay out
To slack off a line, or let it run out.
Pear-shaped link
A shackle or detachable link used to connect a small fitting or chain to a larger
fitting or chain.
Pelican hook
A hook which can be opened while under a strain by knocking away a locking ring
which holds it closed; used to provide an instantaneous release.
Pendant (pendant rig)
A length of wire rope, chain, or fiber line used to facilitate connecting
longer lengths of the same; a single wire or chain that leads from the apex of a towing bridle to the
towline; a length of wire used as an underrider wire in a “Christmas Tree” rig.
Period of roll
The time occupied in performing one double oscillation or roll of a vessel, as from
port to starboard and back to port.
Permeability
The characteristics of a material which allow a liquid or gas to pass through
Plate shackle
A connecting device made up of two metal plates and bolts, used to connect the
towing pendant and the towline, or to serve as a connecting unit in beach gear.
Platform
A partial deck.
Plating, shell
The plating forming the outer skin of a vessel. In addition to constituting a watertight
envelope to the hull, it contributes largely to the strength of the vessel.
Port
The left-hand side of a ship when looking forward; the opposite of starboard
Poured socket
A wire rope termination installed by pouring molten zinc over splayed wire,
often referred to as spelter socket.
Power block (transport block)
A portable, hydraulic motor-driven line sheave; provides back
tension to the traction winch.
Preventer
Any line, wire, or chain whose general purpose is to act as a safeguard in case something
else carries away.
Preventer hawser
A hawser secured to the chain as a preventer.
Proof strain
The test load applied to anchors, chains, or other parts, fittings, or structures to
demonstrate proper design, construction, and material.
Proof strength
The strength of a material, part, or structure, at which it has been proved by test
to possess.
Prow
The part of the bow above the waterline.
“Pudding”
Chafing gear used to protect such items as a towline or spar.
Purchase
A general term for any mechanical arrangement of blocks and tackle for multiplying
force; any mechanical advantage which increases the power applied.
Quarter rollers
Rollers mounted in the forward and stem waists of a tug for mooring, beach
gear, and other similar evolutions.
Reeving
The threading of a line or wire through a block, sheave, or other parts of a wire rope
system.
Resistance
A force that retards, hinders, or opposes motion.
Riding chocks
The chock on deck through which the anchor chain or towing gear passes
inboard.
Risk assessment
The identification of the potential hazard; the parameters that determine the
degree of hazard.
Roller chock
A chock fitted with a roller.
Rope
A flexible, heavy cord of twisted hemp or other fiber.
Roundings
Condemned rope under 4 inches in diameter used to wrap around a rope to prevent
chafing.
Run out
To send out, as to run out a towing hawser
Safe working load (SWL)
The proper load that a rope or working gear may carry economically
and safely.
Safety factor
A multiple representing extra strength over maximum intended stress.
Safety shackle
A connecting device similar to the common shackle, except that a hole is drilled
in the bolt to accommodate a cotter key for the purpose of locking the nut on the bolt.
Sag (Sagging)
Distortion of a ship's hull in which the keel droops downward in the middle; the
deformation or yielding caused when the middle portion of a structure or ship settles or sinks
below its designed or accustomed position. The reverse of hogging.
Salvage towing
Special towing where a discarded, wrecked, sunk, or damaged ship is rescued or
saved.
Sampson post
A strong vertical post that supports cargo booms.
Scantlings
A term applied to the dimensions of the frames, girders, plating, etc., of a ship’s
structure.
Scope
The amount of towline anchor cable out.
Scow
A large, open, usually flat-bottomed boat for transporting sand, gravel, or mud.
Screw-pin shackle
A type of shackle in which the pin passes through one side of the shackle and
threads into the other side of it to form a closure.
Screw stopper
A chain stopper fitted with a turnbuckle.
Sea anchor
A device, usually of wood and/or canvas, streamed by a vessel or boat in heavy
weather to, hold the bow, side or stem up to the sea
Seaway
The motion of the sea when clear of shoal water.
Seize
To bind with small stuff, as one rope to another or a rope to a spar.
Serving
To wrap any small stuff tightly around a rope that may have been previously wound and
parcelled.
Shackle (anchor, chain)
U-shaped metal fittings closed at the open end with a pin; used to connect
wire, chain, padeyes, etc. The anchor type has an exaggerated bow; the chain type has parallel
sides.
Shackle bolt
A pin or bolt that passes through both eyes of a shackle and completes the link.
'Me bolt may be secured by a pin through each end, or a pin through one end and through the eye,
or by having one end and one eye threaded, or one end headed and a pin through the other.
Sheer legs
A rig for handling heavy weights, consisting of an A-frame of timber or steel with the
top overhanging the base, having the lower ends fixed or pivoted and the top ends held either by
fixed stays or by topping lifts which permit change of slope of the legs. Tackles are secured at the
top of the frame through which the hoisting rope or cable is run. Sometimes called “sheers.”
Sheave
A pulley with a rim used to support or guide a rope in operation.
Shot
A standard length of chain; 15 fathoms (90 feet
Side-slipping
Moving sideways through the water.
Side plating
A term applied to the plating above the bilge in the main body of a vessel; also to
the sides of deckhouses, or to the vertical sides of enclosed plated structures
Situation Report (SITREP
A special report generally informal in nature, required to keep
higher authority advised. Prescribed under certain predictable circumstances, but may also be
required at any time.
Skeg
The extreme after part of the keel of a vessel; the portion that supports the rudder post and
stern post.
Skin
The term usually applied to a vessel’s outside planking or plating forming the watertight
envelope over the framework. It is also applied to the inner-bottom plating when it is called an
inner skin.
Slack
Not fully extended as applied to a rope; the opposite of taut; to “slack away” means to pay
out a rope or cable by carefully releasing the tension, while still retaining control; to “slack off”
means to ease up, or lessen the degree of tautness.
Sling
A length of chain or rope employed in handling weights with a crane or davit. The rods,
chains, or ropes attached near the bow and stem of a small boat into which the davit or crane
tackle is hooked. The chain or rope supporting the yard at the masthead.
Slip stopper
A chain stopper hooked or shackled to the deck and fitted with a slip-hook for holding
the towline.
Small stuff
Any small-circumference line used to seize or serve larger lines
Snapback
The force generated when a line carries away
“Snorter”
Four lines with a common eye.
Socket
A wire rope termination attached by zinc or resin. Sockets poured with resin are not
approved for towing. See poured socket.
Span
The distance between any two similar members, as the span of the frames. The of a member
between its supports, as the span of a girder. A rope whose ends are both made fast some distance
apart, the bight having attached to it a topping lift, tackle, etc. connecting two davit heads so
that when one davit is turned the other follows.
Spanish windlass
A device to exert force in bringing together two parts of a rope for any purpose.
Shortening a pair of parallel lines by twisting them with a lever inserted between them at a
right angle to their axis.
Splay
To unlay and broom the bitter end of a wire rope, usually done preparatory to attaching a
socket.
Spliced eye
A wire rope termination formed by unlaying the rope and intertwining the strands to
form an eye.
Spooling
Winding a rope on a reel or drum.
Spring
A mooring or docking line leading at an angle less than 45 degrees with the fore-and-aft
lines of the vessel. Used to turn a vessel or prevent it from moving ahead or astern.
Spring lay rope
A rope combined of rope fiber and wire, used to spring a ship.
Spring, stretcher
A pendant or grommet used to dampen towline surges.
Stability
The tendency which a vessel has to return to the upright position after the removal of
an external force which inclined her away from that position. To have stability, a vessel must be
in a state of equilibrium.
Stability, range of
The number of degrees through which a vessel rolls or lists before losing stability.
Starboard
The right-hand side of a ship when looking forward. Opposite of “port.
Static load
The force applied by deadweight, often referred to as the average or mean load
Stem
The bow of a ship.
Stern
The aftermost section of a ship.
Stern rollers
The horizontal and vertical rollers at the stem of a tug used to lead, capture, and
control the tow hawser.
Stiff (stiffness
The tendency of a vessel to remain in the upright position, or a measure of the
rapidity with which she returns to that position after having been inclined from it by an external
force.
Stiffener
An angle bar, T-bar, channel, etc., used to stiffen plating of a bulkhead, etc.
Stopper
A short length of rope secured at one end and used in order to stop it from running.
Stopper hitch
Two rolling hitches backed up with half-hitches to secure lines or wire
Strain
To draw or stretch tight; to injure or weaken by force, pressure, etc.; to stretch or force
beyond the normal, customary limits; to change the form or size of, by applying external force;
the measure of the alteration of form which a solid body undergoes when under the influence of a
given stress.
Strake
A term applied to a continuous row of plates. The strakes of shell plating are usually lettered,
starting with “A”, at the bottom row or garboard strake.
Strake, bilge
A term applied to a strake of outside plating running in the way of the bilge
Strand
An element of a rope consisting of a number of rope yams twisted together; and, in a
wire rope, of a primary assemblage of wires.
Stranded
To drive or run aground; to beach.
Strap
A ring of wire or line, made by splicing the ends together, used for handling weight, etc.
Stream
To extend, or increase, the scope of the tow hawser
Strength member
Any plate or shape which contributes to the strength of the vessel. Some
members may be strength members when considering longitudinal strength but not when considering
transverse strength, and vice versa.
Stress
The intensity of the force which tends to alter the form of a solid body; also, the equal and
opposite resistance offered by the body to a change of form.
Stringer
A term applied to a fore-and-aft girder running along the side of a ship and also to the
outboard strake of plating on any deck. The side pieces of a ladder or staircase into which the
treads and risers are fastened.
Stud-link
A chain link with a bar fitted across the middle to prevent the chain from kinking
Surge
To hold a line taut on a winch drum without hauling in; to slack off a line or let it slip
around a fitting. A sudden transient increase in electrical current. A violent or sudden increase in
load on awire, line, winch, etc.
Surge load
Suddenstrain on a towline caused by the pitching, shearing, or yawing of the tow
and/or the towing ship.
Swage
To connect, splice, or terminate wire rope by use of steel fittings installed under
extremely high pressure.
Swash bulkheads
Longitudinal or transverse nontight bulkheads fitted in a tank to decrease the
swashing action of the liquid contents. A plate serving this purpose is called a swash plate.
Swivel
A removable anchor chain link fitted to revolve freely to keep turns out of a chain
Tackle
An arrangement of ropes and blocks to give a mechanical advantage; a purchase; any
combination of ropes and blocks that multiplies power. Also applied to a single whip which does
not multiply power but simply changes direction.
Tee bar
A rolled or extruded structural shape having a cross section shaped like the letter “T.”
Thimble
A grooved metal buffer fitted snugly into an eye splice.
Tiller (Tiller arm
Casting or forging attached to the rudder stock.
Tonnage
Tonnage is a description of the cargo capacity of a merchant ship. Tonnage is a volume
measurement and does not indicate displacement.
Topside
That portion of the side of the hull which is above the designed waterline; on or above
the weather deck.
Tow pad
A padeye designated or dedicated as the connection to the tow hawser or bridle. See
padeye.
Traction winch
A capstan-like device that generates line tension in synthetic or fiber lines.
Tension is generated by friction between the line and traction heads.
Transverse.
At right angles to the fore-and-aft centerline
Transverse frames
Vertical athwartship members forming the ribs.
Trim
Fore-and-aft inclination measured as the difference between the drafts at the forward and
after perpendiculars. Ships designed to have drag - a deeper draft aft than forward - have zero trim
whenfloating at or parallel to the design drafts. Excessive trim, usually considered to be morethan
one percent of the length of the ship, can be dangerous because it increases the danger of plunging
(sinking by the bow or stem).
Tumble home
The decreasing of a vessel's beam above the waterline as it approaches the rail.
Opposite of “flare.”
Turnbuckle
A metal appliance consisting of a threaded link bolt and a pair of opposite-threaded
screws, capable of being set up or slacked off, and used for setting up standing rigging or stoppers.
Two-blocked
When the two blocks of a tackle have been drawn together or tightened.
Ullage
The void above a liquid surface in a tank, and the measurement of this void.
Vapor
Any substance in the gaseous state that is usually a liquid or solid.
Veer
To pay out chain
Veer away
To pay out chain under control by reversing winch or windlass rather than by surging.
Waterline
A term used to describe a line drawn parallel to the molded baseline and at a certain
height above it, as the 10-foot waterline. It represents a plane parallel to the surface of the water
when the vessel is floating on an even keel, i.e., without trim. In the body plan and the sheer plan
it is a straight line, but in the plan view of the lines it shows the contour of the hull line at the
given distance above the baseline. Used also to describe the line of intersection of the surface of
the water with the hull of the ship at any draft and any condition of trim.
Watertight compartment
A space or compartment within a ship having its top, bottom, and
sides constructed in such a manner as to prevent the leakage of water into or from the space unless
the compartment is ruptured.
Web
The vertical portion of a beam; the athwartship portion of a frame; the portion of a girder
between the flanges.
Web frame
A built-up frame to provide extra strength consisting of a web plate with flanges on
its edges, placed several frame spaces apart, with the smaller, regular frames in between.
Whip
A term loosely applied to any tackle used for hoisting light weights and serves to designate
the use to which a tackle is put, rather than to the method of reeving the tackle.
Wildcat
A special type of drum whose faces are formed to fit the links of a chain of given size
Winch
An electric, hydraulic, or steam machine aboard ship used for hauling in lines, wire, or
chain; a hoisting or pulling machine fitted with a horizontal single or double drum. A small drum
is generally fitted on one or both ends of the shaft supporting the hoisting drum. These small
drums are called gypsies or winch heads.
Windlass
An apparatus in which horizontal or vertical drums or gypsies and wildcats are operated
by means of a steam engine or motor for the purpose of handling heavy anchor chains, hawsers,
etc.
Wire rope
Rope made of wire strands twisted together, as distinguished from the more common
and weaker fiber rope. Sometimes called a cable, or wire cable.
Wire rope pendant
A long wire strap.
Worming
Filling the lays of line or wire before parcelling
Yard tug
A term used to describe harbor tugs used in berthing operations; e.g., YTL, YTM, and
YTB Class of tugs.
Yaw
Failure of a vessel to hold a steady course because of forces of wind, sea, damage to vessel,
etc.
Yellow gear
Salvage machinery.