Abreast - A second boat parallel too.
Aft - Towards the stern of the boat
Aloft - Above the deck
Aloft - Above the hull; in the air
Amidship - Between fore and aft, the middle of the boat
Amidships - Near the middle of a boat
Anchor - Danforth - Plow (CQR) - Bruce
Anchor Lights - For vessels under 50 meters - A single white all around light
Anchorage - A harbor suitable and usually designated as a place to anchor
Anti-Ventilation Plate - The horizontal plate just above the prop, sometimes called the anti-cavitation plate
Astern - Behind the boat; to the rear
Astern - Behind the stern of the boat
Athwart or Athwartship - Across the beam of a boat
Awash - Barely floating; mostly submerged or, what my boat needs
Aweigh - Anchor off the bottom
Bahamian Moor - Two anchors set opposite each other, parallel to the current, with the boat attached in the center to minimize swing into a shore or because of current shift. Must let out twice the necessary rode to set the second anchor
Bail - The action of removing water from the hold of bilge of the boat
Ballast - Weight in a boat which affects the boats trim
Ballast - Weight place in the bottom of a boat to give it stability
Bar - Sand, mud or debris shoal
Barometric Effect - One inch drop in barometer will raise the tide approximately one foot. Dropping barometer (> 005”/hour) indicates bad weather coming
Batten Down - Close all openings and hatches, fasten down lose gear
Beam - Widest width of the boat
Bear Right - To starboard when heading straight on another vessel. If entering same corner return the signal with the same blast
Bearing - Compass direction from one location to another Give in 3 digits “098°”
Becket - A loop or eye made in the end of a rope or wire
Below - Inside a boat
Berth - A place to sleep in a boat or a place to make fast a boat
Berth - A sleeping area in a boat or, a place to moor a boat
Boating Industry Association Bight (BIA) - Loop or middle part of a line
Bilge - Lowest interior portion of a boat where water could collect
Bilge - The deepest part of the inside of a boat
Bilge Rats- Boat mechanics
Bitt - A strong piece post at the bow or stern to attach a towing, anchor or docking line
Bitter End - The end of the rode that is not attached to the anchor
Black Box - Tech talk for ignition module or Electronic Control Module (ECM) Also referred to as, power pack and ignition amplifier
Blind Bend Signal - When approaching a blind curve in a narrow channel sound a 4 to 6 second blast and keep right
Blister - Used to describe water entry between the gel-coat and the fiberglass skin of a boat
Boat Hook - A pole with a hook on one end used to catch a ring bolt or line when coming alongside a pier or mooring
Boat Speed - Speed on the water not including current versus true speed which includes current
Bollard - Massive metal post on a dock or pier that heavy ship lines can wrap around
Bow - The front of a boat
Bow & Beam Bearings - Distance traveled when a stationary landmark moves from 45° off the bow to 90° (abeam) is the distance from the landmark when boat was abeam the landmark (you can double any angle from 15° to 45°)
Bow Line - Docking line that runs from the bow to further forward on the dock. This allows some boat movement with the tide
Bow Line - Line going forward diagonally from a boat's bow to secure it
Bow steer - To "over trim" the boat to the point where the nose of the boat starts to steer
Breast Line - Docking line that runs at right angle from side of the boat as compared to spring lines which are angled from the boat to the dock Not to be used with a significant tide
Breast Line - Line going sideways from a boat
Bridge - Upper helm station in some motorboats
Bridle - Short rope with each end secured to the boat so that another line can be attached to its center. Often used when towing another boat. Can be used while anchoring to angle boat into the waves
Broaching - Sudden, unplanned and uncontrolled turning of a vessel so that the hull is broadside to the seas or the wind
Buoy - Any floating marker that is secured in place
Buoy - Floating aid to navigation
Can - Cylinder shaped buoy used for mooring
Capsize - Turn upside down or what increases as your boat gets nicer
Cardinal Points - Four principal compass points, N - S - E – W
Cast Iron Genoa- A sail boat's engine
Cast Off - Let go of the lines when leaving the dock or mooring
Cavitate- The entry of air into the prop
Chafe - To damage a line by rubbing
Chafe - Wearing through of a line, sail, etc from rubbing
Charge Coil - Voltage generator used to power ignition modules, mostly used on outboards
Chart - Map of navigable waters
Chart - Navigational maps showing water depth and ATON’s. Don’t call a chart a map
Chart Scale - 50,000 to 1 = large scale 500,000 to 1 = small scale
Chine walk- Dangerously uncontrolled, side to side motion associated with high speed operation
Chock - A metal guide attached to the edge of the deck which is used to guide mooring or anchor lines
Claw off - Clear a Lee Shore
Cleat - A fitting used to secure a line under strain
Coaming - Wind protection around a cockpit
Cockpit - Outside sitting area in a boat
Collision Course - A unchanged relative bearing with another approaching vessel
Compass Rose - Double circle with magnetic degrees in the inner circle and true degrees in the outer circle
Compensated Compass - Compass that has been adjusted to correct for deviation
Compass Readings - Correcting means taking compass readings and correcting for deviation and variation to get corrected
Course - Intended direction of travel. If plotted DR course on a chart write compass heading with “M” or “T” if course is compass reading is magnetic or true
Crossing Channels or Shipping Lanes - Do at a right angle
Cubic Inch Displacement (CID) - Speed
Current - Horizontal movement on water
Current - Tidal current, ocean current, leeway, minor steering errors
Current Arrow - A line drawn the distance the current travels in one hour from a fixed position on the chart
Current Triangle - Draw line the distance the boat covers in an hour from ending point of the current arrow to where it intersects the course line, this is the current corrected heading distance from original fixed point is True Speed or Speed Made Good (SMG)
Danger Bearing - A bearing to a marker that needs to be greater or lesser to in order to be sure that a dangerous condition can be avoided
Danger Signal - At least five short blasts which means there is a failure to understand intentions or action is not being taken to avoid collision
Danger Zone - A powered vessel must give way to any approaching other vessel from dead ahead to 225° past abeam on the starboard side. The give way vessel should not turn to port for approaching vessels forward of it’s beam but starboard to pass to the stern of the approaching vessel
Datum - Chart sounding water depth that would occur at average lowest tide
Day Beacon - Unlighted fixed aid to navigation
Driving a Boat While Intoxicated - DBWI
Dead Reckoning - Determining your position by distance and course run
Dead Reckoning (DR) - Boat’s location is determined by direction and distance from a previous know location, used to be called “Deduced Reckoning”
Depth Meter or Fathometer - Instrument used to determine soundings or depth of water
Deviation - Iron, steel or magnets that are within 3 to 5 feet of a compass can effect its reading. The deviation will vary depending on the direction of the boat. To determine deviation take handheld compass readings from centerline of the boat, well behind the compass. If boat compass has more degrees it is a West deviation
Deviation Table - Lists the amount and direction of deviation depending on boat bearing maximum error will be either east–west or north–south headings
Displacement - Weight of the water displaced by the boat
Displacement Hull - Boat is meant to move through the water, not skim over it
Distance from a Marker - Calculate using bow and beam bearings from a single marker
Distress Signals - The following signals indicate need for immediate help:
An operating Emergency Position Indicator Radio Beacon
Call VHF channel 16 radio – include name, location, type of distress
Continuous blast of fog horn
Firing gun or explosions at one minute interval
International Code Flags “N” over “C” ( not in command )
Orange signal flag with black square and black ball
Orange smoke signals
Red rockets or flares
Slow and repeated raising of your out stretched arms
SOS made by any means
Visible open flames on the vessel (rags burning in a bucket)
Draft - Depth of the keel
Draft - Least depth of water needed to allow a boat to clear the bottom
Draw Bridge Signal - one long blast and three short blasts
Drift - Speed of a current's flow
Drift - The boat movement leeway or sideways, can be speed of the current in knots
Drogue - A sea anchor is attached to the bow a drogue is attached to the stern, it can be a line with knots towed astern off a dingy to keep it from running into the back of the boat in a following sea
Drying Height - Height above water an obstacle (rock) will be exposed if water is at datum tide height will define how much is actually exposed
Eddy Currents or Tidal Eddies - Counter current to main body of water flow along shoreline this happens on the inside portion of turning water
Estimated Position (EP) - Plot DR on chart and line of position (LOP) from a marker then correct the dead reckoning (DR) location by plotting 90° from DR location to LOP. This is not a FIX
Fair Lead - A line unobstructed between its terminals, such as between a bow chock and a piling
Fairing Block- Shim installed to adjust the angle of a mounted item
Fathoms - Six feet, chart may list fathoms and feet together or fathoms and a fraction
Fender - Bumper placed beside the haul to protect it when docking
Fender - Protection for a boat
Fix - Boats location on a chart is determined by crossing two or more bearings
Flake - Folding lines loosely or in figure eights so they can run out without fouling
Flapper - Short for flapper valve or shutter valve, installed in the exhaust system of sterndrive engines to prevent backwash of water into the engine if the engine were to shut down unexpectedly
Flashing Buoy - Determine its position on chart using flash color and sequence
Flemish - To coil excess line in a spiral on the deck or dock
Float Plan - A plan given to a responsible person on shore of your intended cruise or destination
Flood - Incoming tide
Fluke - Digging spade portion of an anchor
Fluxgate Compass – Electronic compass with a remote magnetic direction sensor
Fog - Any form of haze or restricted visibility. Plot DR carefully in fog
Fog Horn Signals – Fog signals every 2 minutes required for all vessels over 12 meters. One long – two short = any vessel with restricted maneuverability. One long = power vessel underway. Two long = Power vessel stopped. One short – one long - one short = any vessel at anchor. Signals may be 5 to 10 minutes apart in open water
Fog Signal Response - Stop or reduce to minimum forward motion if fog signal is heard: forward of the beam in close proximity or another vessel or lights are seen loaming ahead, turn off the motor occasionally to listen for 2 minutes
Following Sea - Waves coming from your stern
Forward - Toward the bow; ahead
Freeboard - Distance from the top of the hull to the top of the water
Freeboard - Height of a boat's gunwale above the water
Fresh Water Cooled - An engine that is cooled by anti-freeze run through a heat exchanger that is cooled by sea water
Galley - A boat's kitchen (where the term "Galley Slave" came from)
Gel-Coat - Colored, two part plastic finish on fiberglass boats
Gimbal - A device used for suspending the compass or a stove so it remains level
Gimbal Bearing- Drive shaft support bearing located in the gimbal housing
Gimbal Housing- Supporting part of the sterndrive, bolted to the transom
Gimbal Ring - Part of the sterndrive that looks like a horse collar and supports the sterndrive and allows it to swivel
NOTE: Give way to any vessel that is: too large to maneuver, a fishing vessel, restricted to a channel, not under command, a vessel you are passing, a vessel to your starboard
Give Way Vessel - Vessel that must change course or stop. Never cut across the bow of stand-on vessel
Global Positioning - Latitude is expressed first with “N or S” to define if it is above or below the equator Longitude is expressed second noting “E” or “W” of Greenwich
Gnomonic Projection - A chart with Longitude lines that are straight while Latitude lines are curved so that the shortest distance between any two points is a straight line. This straight line becomes a “Great Circle Route” on a Mercator Chart which is a curved path but the shortest route. A Rhumb-Line course is a straight line drawn on a Mercator Chart
Great Circle - Shortest distance between two points because of the curvature of the Earth Green, left on return, square, can, odd #, GongGreen/Red un-numbered buoys - Channel split - use top color to determine main channel
Ground Tackle - Anchor, rode, etc used to secure a boat to a mooring
Ground Tackle - Gear used for anchoring
Grounded – If grounded: - check for leaks - check tide status – check motor inlets make soundings all around the boat - reverse can push sand around the keel set up kedging anchor – try rocking boat or shifting weight
Gunwale - The railing of the boat at deck level
Gunwale - The top edge of a boat's hull
GWL - Gunwale length
Hatch - Window mounted horizontally in the cabin roof
Head - A boat's toilet; or the top corner of the sail
Head Seas - Waves coming towards the bow its best to steer over waves at a 45° angle
Heading - Direction boat is pointing at any moment
Headstay - Wire from the bow to the upper part of a sailboat's mast
Headway - Moving forward
Heel - Sideways learning of a boat due to the wind
High Energy Ignition (HEI)
Helm - A boat's steering area; also the steering gearHelm - Tiller or wheel mechanism by which the boat is steered
High Water - The tide's highest point before it starts to fall
Horseshoe Buoy - PFD in the shape of a U, mounted on the stern for emergency MOB
Hull - A boat's bottom shell
Hull Speed - Theoretical top speed for a displacement boat (sailboat)
In the Lee - Protected from the wind
Insetting Effect - Current tends to flow into coastal bays – dangerous at night or in fog
Jetty - A solid structure projecting out from the shore. Sometimes used to protect a harbor
Kedging Anchor - Dropping an anchor behind a grounded boat using a dingy or even swimming it out using a flotation cushion to support the anchor
Knot - Nautical mile (6,076 ft) per hour ( a measure of speed)
Knot - Nautical unit of speed – one nautical mile per hour ( 115 mph )
Lanyard - A line fastened to an object, such as a bail or knife or other small object for the purpose of securing it
Latitude - Lines that are parallel to the equator - Parallels of Latitude each degree is 60 (nautical) miles – each minute is 1 nautical mil.e Only use latitude minutes on side of chart for stepping off mileage
Lazarette - A small space below deck, usually aft, where an outboard motor or spare parts are kept
Leaving a Berth - Inland rule is one prolonged blast
Lee of the Land - Near a shore which provides protection from wind and waves
Lee Shore - Land downwind of a boat
Lee Shore - Shore that has wind blowing onto it from the water. Where as “In the Lee” refers to a being protected from the wind
Leeward - Downwind; away from the source of wind
Leeway - Boat's sideways movement through the water, due to the wind pushing it to leeward
Length at the Water Line (LWL) Length Overall (LOA)
Line - A rope in use aboard a vessel
Line of Position (LOP) - A single magnetic bearing from a stationary marker “Magnetic Bearing” (MB) is another term for LOP
List - Continuous leaning to one side
List - Sideways tilt of a boat due to poor boat trim
Length Overall (LOA) - Centerline length of hull including molded in pulpits and platforms
Log - A device that gives a direct readout of miles run. Distance measuring device
Longitude - Lines that meet at the North and South poles - Meridians of Longitude
Long Range Aid to Navigation (LORAN) - Pairs of Radio beacons that has a distance of 800 Miles. Difference in receiving time of each signal indicates your line of position
Lubber’s Line - A short post or line inside a compass used as a reference point for steering or determining a bearing
Magnetic Rose - Inner circle of chart compass giving magnetic corrected compass for a particular year. Need to correct magnetic rose for older charts
Magnetic Variation - Difference between true compass (TC) and magnetic compass (MC)
Make Fast - Securing a boat at a dock or landing. You don’t tie up a boat
Make Way - To propel yourself through the water (what some boat mechanics do at the singles bar)
Man Overboard (MOB) – Shout “man overboard (starboard/port), all hands on deck”, assign a spotter to do nothing but keep site of and pointing at the MOB, throw a flotation device overboard, note present location, heading and speed
Man Overboard Rig - Flotation device and/or life raft, spotting pole, signaling equipment
Marlin Spike - Pointed tool used for prying tight knots apart
Mast Head Light - White light – Must shine from front to 225° aft of the beam/used when under power
Maximum Velocity - Maximum velocity of tidal current half way between slack periods
Mediterranean Mooring - Anchor is set straight out from dock, boat is reversed into the dock with fenders in place
NOTE Cleat anchor rode to keep boat just off the dock, use spring lines off the stern to hold boat to dock
Meeting Situation - Two vessels directly approaching each other should each bear starboard and pass “Port to Port”, each vessel can sound one short blast to agree to this, each vessel should sound two short blasts to indicate intention to pass starboard to starboard. Never return a different blast signal
Mercator Chart – Takes a globe and flattens it out so that Lat – Long lines intersect at 90°
Meridian - Line running from North to South Poles that cross the equator at right angles
Mid-Channel Marker - Red and White stripes, may have a white light
Mooring - A place to secure a boat in the water
Mooring - Heavy anchor or weight permanently in position
Mooring Buoy - A buoy fitting with a ring and short tie up line used for mooring a boat to itself
MPI - Multi-Port-Injection, as compared to, EFI - Electronic Fuel Injectors, or TBI - Throttle Body Injection
MSD - Marine Sanitary Device
Nautical Mile - 6076 feet; 115 statute miles
Nautical Mile - Mi on nautical maps is nautical mile 115 land miles = 1 nautical mile or about 2000 yards
Nautical Speed - Knots ( not knots per hr )
Navigation Time - Use 24 hours ( 1400 = 2 pm ) and tenths rather than minutes
Neap Tides - Weakest tides happening during middle of first and third quarter of the moon versus spring tides at the full and new moon
National Marine Manufacturers Association - NMMA
Noise Making Buoy - Floating buoy with a bell, gong, whistle or horn that sounds as the buoy is rocked in the water
Nun Buoy- Shaped like a rocket's nose cone
Overtaken - Vessel being overtaken must hold course
Overtaking Situation - Overtaking vessels must keep out of the way of the vessel being
Padeye - Metal loop that a line runs through
Painter - Short rope secured to bow of a small boat and used for fastening her to the dock
Parallel Rulers - Used to determining Line of Position ( LOP)
Pay Out - To release a line in a controlled manner such as the anchor rode
Pelorus - Compass like card that can be clamped in a fixed position. The card has 360° markings & sight vanes 0° is pointed to either magnetic north (dumb compass) or the boats current heading
Pennant - A small signal flag
Permission - Always ask permission to come aboard someone else’s boat
Petcock - Often used to describe the sea water drain valves an inboard motor
PFD - Type I off shore – Type II near shore – Type III flotation aid - Type IV throw able
Piloting - Navigating by using visual references and water depth
Pitch Pole - Riding down such a steep wave that the bow plows into the wave trough and the wave pushes the stern up and over
Pitching - Rising and falling of the bow versus Roll which is sideways rocking
Porpoise (Porpoising) - The rhythmic bouncing of the nose of a planing boat, often caused by over-trim or hull irregularities
Port - Window on a boat
Port - The left side of the boat as one faces forward – red light side light near the bow. Also an opening for light or ventilation in the side of a vessel or a shore location to dock and maintain a vessel
Port (To) - By a boat's left side
Port Side - A boat's left side
Port Side Bow Light is Red – Starboard side bow light is green
Position by Line of Soundings - Measure distance between sounding depths and make scale drawing to use to match chart soundings near plotted course to determine approximate position
Privileged Vessel - Vessel having the right of way in a crossing situation
Prop Walk - Sideward force created by a spinning propeller Right hand prop (clockwise)
Prop Wash - The intersection of water, behind the boat, initially displaced by hull movement through the water
Propellers - Right hand propeller spins clockwise, left hand spins counter clockwise. Most single screw driven vessels are right hand propspulls the stern to starboard in forward and to port in reverse, mostly affects reverse
Quarter - Side of a boat abaft the beam
Radar - Can be seen 20% beyond the horizon. Not useful in the rain
Radiation Fog - Cooler land mass causes fog over land
Radio Direction Finder (RDF) - Instrument used to obtain a bearing to a marine radio beacon. Radio beacons identified on the chart with signal frequency. Locate direction when signal is null, can be 5° to 10° off
Rafting - Two or more vessels made fast side by side, boats are held by first anchor, rafted boats should set their own anchor 45° off the first boat to allow them to swing free later on their own anchor
Range - The distance a boat can travel using the fuel it can store
Range Lights - Two lights one above the other that line up with center of channel steer toward lower light to re-gain alignment
Rectifier - In outboard motors, this item converts alternating current (AC) to direct current (DC)
Reeved - A line that is passed through a block or hole
Relative Bearing - Direction of an object or other boat in reference to the bow. It can be given in degrees, points per quarter or the twelve hours of a clock with the bow being 12 o’clock and the stern being 6 o’clock
Reverse - Most right hand prop single screw boats will easily reverse to port but need right rudder to back up straight and will reluctantly turn to starboard with reverse headway
Reverse Direction - Slow down, set right rudder and use forward and reverse propeller to swing boat in a small area without changing the rudder position (right prop only)
Rhumb line - A straight line on a Mercator Chart over long distances the Great Circle is the shortest route
Rode - Line (chain or fiber) which joins an anchor to an anchored boat
Rode - The line and chain used to secure the anchor to the boat. Enough length for at least 5 to 1 rode for deepest anchorage sites. Chain should be at least half the length of the boat
Roll - Sideways rocking of a boat versus pitch which is forward to rear rocking
Rolling Hitch - Clove Hitch with two wraps around the bar or rope before knotting
Rudder - Flat board which redirects aims current or propeller wash to steer a boat
Running along a Depth Curve - Guiding a boat parallel to a shore line by following a single depth, can use to help locate a buoy in known depth
Running Fix - Two bearings of the same marker taken at different times and the LOP plotted on a chart. Use time and speed between bearings to determine distance. Measure true distance with calipers, move calipers parallel to DR line until they intersect the two LOP lines
Running Lights - Lights to be displayed by a boat underway at night or in restricted visibility
Scope - Length of anchor rode compared to depth of water at high tide and height to the bow 5 to 1 is considered a minimum with 10 to 1 in bad weather. All chain rodes need a scope of 3 to 1 up to 5 to 1
Scope - Ratio of anchor rode length to vertical distance from the anchor lead (chock or roller) to the bottom
Scull - To move the rudder rapidly back and forth to propel the boat forward (sculling)
Scupper - Water drain hole in the deck of a boat
Scuppers – Drain holes above the waterline (found in the cockpit area)
Sea Anchor - A long line from the bow to a heavy fabric cone that is slightly submerged. Holds the bow into the wind and reduces drift up to 90%. Large opening should be 1 inch for each foot of a boats waterline
Sea Cocks – Valves just inside of the through hulls to close off water or drain lines
Secure - To make safe
Sentinel - Extra weight attached to the rode that is lowered halfway down to pull the anchor line further down
Set - Direction that the current is flowing towards or a boat is drifting
Shackle - A u-shaped stainless fitting with two eyes that a shackle pin attaches to, to close the circle. Can be a quick release
Shift Interrupter - Pressure sensitive switch used to electronically slow the engine down when shifting gears
Shoaling Effect - Faster flowing water over a shallow area causing rough surface condition
Sidelights - A boat's red and green lights
Sidelights - Port side bow is red light - Starboard side bow is green light
Slack Water - Brief period between flood and ebb when horizontal flow stops (2-20 min)
Slack Water - The moment when a tidal current changes direction
Sole - A boat's floor
Sound Bearings - Close eyes to determine direction of sound to obtain a rough bearing to a sound. Marker in desperate situation zig in and out of hearing range of breakers
Sound Signals - Daylight Warning - Only used when boats are within eyesight. These signals are never used in fog. One short blast - I’m altering my course to Starboard. Two short blasts - I’m altering my course to Port. Three short blasts - I’m backing up In international waters no reply is needed. In inland waters show agreement with same return signal. Never reply with a different number of blasts
Soundings - The depth of the water based on the average of the lowest tides
Spar - A type of buoy
Splash Well - The pan area just in front of the transom on outboard boats that helps keep back-wash from entering the cockpit area
Splice - To join rope by tucking the strands together
Spring Line - A line used to keep the boat from moving forward and aft when docked versus the breast lines which are at right angles to the boat Bow spring line starts at the bow while stern spring line starts at the stern
Spring Line - Line secured neat amidships and led ashore mostly forward or aft, to keep a boat from surging ahead or astern
Spring Tides - Strongest tides caused by alignment of sun and moon during full and new moon period
SSB - Single Side Band Radio (often a new option on VHF radios )
Stand Tide - The moment the tide changes direction up or down
Starboard - On or along a boat's right side
Starboard Side - A boat's right side
Steerage - Minimum speed required to control a boats movement
Stern - A boat's back end
Stern - Aft section of the boat
Stern Light - White light which shows abaft a boat underway at night
Stern Lights - White light - 675° each side of stern
Stern Line - Line leading diagonally aft from the stern to secure a boat
Stern Lines - Docking line that often runs from the stern fitting farthest from the dock to further astern on the dock. This allows the boat movement with the tide
Sternway - Boat's backward movement through the water or over the bottom
Sternway - Moving backwards
Stow - To put away
Strake- Contour added to the outside hull bottom, to aid in performance
Stringer - The internal hull bottom ribs used for structure
Stringer Mount - Often used to describe early vintage OMC sterndrive engine packages
Stuffing Box - Fitting that seals and lubricates the propeller shaft where it protrudes through the hull
Sumlog (Knotmeter) - Electronic boat speedometer that also gives distance covered
Swamp - To fill with water
Take a Bearing - Use either a hand held compass or the boats compass to get a magnetic bearing on a buoy or marker or land feature – include deviation with boat compass
Take a Fix - Before nighfall, or when: visibility is decreasing, approaching shallow areas, entering a harbor, and sailing unfamiliar waters TC = True Compass MC = Magnetic Compass CC = Course or Corrected Compass
TCW - Twin cycle, water cooled (as in TCW II and TCW 3 oils)
Tender - A small boat to go back and forth between the shore and the main boat
Tenth of an Hour - Equal to six minutes
Thimble - A ring with a grooved on the outside to make a rope grommet
Three Courses: - True Course “TC” - Magnetic Course “MC” - Corrected Compass “CC”
Through Hull - Where fittings pass through a hull below the waterline
Tidal Current - Horizontal flow of coastal water (flood = inflow - ebb = outflow)
Tidal Current - Horizontal flow of water due to the gravity of the moon and the sun
Tidal Current Tables - Gives set and drift, time of the maximum current and slack water time. Note: Gives set in true direction rather than magnetic. Time is not adjusted for daylight savings. Tidal day is 24 hours and 50 minutes. Tide peaks gain 50 minutes a day
Tidal Range - How far the tide rises and falls
Tide - Rise and fall of coastal waters - 6 hours and 13 minutes between high and low tides
Tide - Vertical movement of water die to gravity of the moon and the sun
Tide Tables - Yearly published water height above charted soundings
Tiller - Handle attached to the rudder, used to steer some boats
Tiller - Steering mechanism that controls the rudder
TnT - Power Trim n Tilt
Topside - On deck
Transom - Most stern portion of the hull
Transom - The outside flat part of a boat's stern
Trigger - The electronic switch that replaced points, often refereed to as a Trigger assembly
Trim - Fore and aft and side to side balance of a boat
Trim Fin - Small fin mounted to the gearcase that helps reduce steering torque
Trim Tab - Flat horizontal adjustable plate mounted to the transom that helps adjust bow up and bow down angle
Trip Line - Line attached to the crown of an anchor to pull a suck anchor loose
Trough - Bottom section of a wave
True Bearing - Bearing or direction taken relative to true North
True Speed or Speed Made Good (SMG) - Actual speed which includes effect of current
Turning - Remember in tight quarters the stern needs to move in opposite direction of the bow and prop walk predominates in reverse. Brief burst of forward throttle with right rudder will drive stern to port. Only in forward does the rudder re-direct the prop thrust. Reverse rudder is much slower to respond
Underway - A boat moving through the water
Variation - The difference between magnetic North and true North
Veer - A change of direction
Vertical Drive - Often used to describe the inboard outboard sterndrive
Visibility Table - Lists the distance from a light appearing on horizon for each foot of height. Square root of height times 117
Wake - The astern waves created by the boat
Wake - Waves made by a boat's movement through the water (the disturbance your wife makes when you tell her your going boating)
Walter Drive - V drive inboard transmission
Wash - Flow of water from the action of the propeller(s)
Watches - Periods of on deck duty, usually four hours long (dog watches are two hours)
Weather Indicators - If wind shifts opposite of the movement of the sun (coming from the West and then coming from the East) expect bad weather. If it shifts with the sun expect good weather. Lightning from West or Northwest will reach you, South or Southwest will pass by
Weigh Anchor - Lift the anchor
Well Found - Well equipped and if everything is in order it is “ship-shape”
Whip - To bind the strands of a line’s end with yarn or cord
White Light with Short Long Flashes - Mid-channel buoy
Wind Current Effect - Wind against current - rougher water, wind with current - calmer water
Windlass - A rotating drum used to haul in a line or a chain
Windward - Toward or into the source of the wind
Windward - Toward the wind, opposite of leeward
Windward Side - Side of the boat the wind is hitting - opposite side boom is on
Water Line Length - WLL
Yaw - Pushed off course by wave action or other force
Yawing - Tendency of a powerboat at anchor to drift around
Yellow Buoys - Indicate specific areas (military, fishing, anchorage, etc)
