Definitions and Mnemonics for
Sailors
About the COLREGS
The word "COLREGS" is a common abbreviation for the International Regulations for Prevention of
Collisions at Sea, which is the worldwide agreement on how boats should behave when in international
waters. Most of these mnemonic are intended to help you remember important parts of the COLREGS,
although some are specific to inland waterways in the United States (which have slightly different rules).
When the mnemonics conflict with your interpretation of the COLREGS, remember that the COLREGS are
the law and the mnemonics are only a memory aid!
Navigation Light Combinations
One of the most complex areas of boating is the light combinations used to indicate
various types of ships at night. Luckily, there are also lots of standard mnemonics. Most
of these were provided by Farnes Quinn and Steve Hodgson.
Running Lights
The most fundamental navigation lights are the running lights required on all boats
over 5 meters. The basic running lights are white to the stern of the boat, red to port, and
green to starboard. The colored lights are visible from forward of the boat as well as the
sides. The three running lights may be mounted in a number of ways, separately or
combined, high or low, but must always be masked so that you see the appropriate color
from the each direction.
There are several useful mnemonics related to the color of the running lights. First,
remember that port wine is red, so the red running light is on the left side of the boat.
Second, you see stars in good weather, which is when you like to go out on the water, so
green for go equals starboard (invented by Alistair Barclay). Third, stoplights (traffic
signals) in most places show red when you should stop, green when you should go. The
running lights and the right-of-way rules are arranged so that if you see another boat's
port (red) running light and there is no other rule to tell you what to do, you should give
way ("stop"), while if you see green, you should maintain course and speed ("go"). Red
means stop, green means go.
A fourth mnemonic, suggested by Peter W. Meek, is Red Left Port. The image is of a
red-headed sailor going to sea, where he belongs (not some nasty old port). This
mnemonic has the advantage that it also serves for buoyage system "B" and for
remembering that port is the left side of the boat.
In addition to the three-colored running lights used by all boats, a powerboat must show a
white masthead light visible from the front. This light must be mounted higher than the
running lights. Depending your angle relative to the powerboat, the masthead light might
or might not appear to be in line with the visible running light, but it will always be
higher. (From the stern, only the stern light is visible, regardless of the type of
propulsion. This is because you aren't going to collide with a faster boat that's ahead of
you, and if you're the faster one, you have to give way regardless of propulsion method.
See the overtaken-wins rule in the right-of-way rules.)
To summarize, if you see , you're looking at the port side of a sailboat. Similarly,
shows the starboard side of a sailing machine. means you're seeing somebody's stern,
but you don't know whether it's power or sail.
indicates the port side of a power vessel
(note that the two lights won't necessarily be lined up as shown here). Finally,
you're seeing the starboard side of a power boat.
means
Mast Lights
Mast lights are shown in addition to running lights to identify vessels more precisely than
simply "I'm a boat." If a boat has no mast light at all, it's a sailboat (see above). (Note that
a three-colored running light, as described above, isn't a "mast light" even if it's mounted
at the top of a sailboat's mast, nor is the white masthead light shown by all power boats.
Confused enough?)
Other, more complex mast light combinations indicate the operational status of the boat.
They are usually, though not always, shown all-around:
Red over Red
This boat is dead
(or "Captain's in bed" or "Captain's in the head," or "Captain's dead"). Two red
lights in a vertical line indicate a vessel "not under command." In other words,
when you see this combination, don't expect them to do anything to avoid you,
regardless of what the right-of-way rules say. You should show these lights any
time there is a circumstance, such as engine or steering failure, that prevents you
from complying with the rules of the road.
An alternative is Two reds equal too dangerous to command.
Red over Green
Sailing machine
(or "sailing is keen"). Note that this is the less-used of the two sailboat lighting
combinations. Most sailboats identify themselves by the lackof a white masthead
light visible to 22.5 degrees abaft the beam. Don't assume that lack of red-overgreen means it's under power!
Red over White
Fishing boat lights
If the fishing gear extends over 150 meters (492 feet) from the boat, an all-around
white light must indicate the direction.
They are fishing for red salmon. or They are stopped over a white fish (
Green over White
Trawling tonight
Note that this is different from the general fishing lights.
They may trawl up a piece of green seaweed. or White fish under green sea).
White over White
Short tug/tow in sight
A short tow is under 200 meters (656 feet).
White over White over White
Long tug/tow in sight
A long tow is over 200 meters (656 feet).
Red over Red over Red
Rudder Rubbing Rocks
This refers to a vessel constrained by her draft. It applies only under the
international rules.
White over Red
Pilot ahead
A pilot boat, waiting for "customers," displays this combination so that boats
needing a pilot will be able to find it. Pilot boats also display this combination
when waiting to pick up a pilot who is finished with a customer. (The customer
boat displays it normal running lights, as appropriate.)
An alternative mnemonicis White hat over red face. Or "Pilot in bed" as an
alternative.
Red over White over Red
Red When Restricted
A vessel showing this combination is restricted in its ability to maneuver. Stay
away! Examples include vessels servicing navigation marks, cables, pipelines;
vessels dredging, surveying, or carrying out under water operations (such as dive
boats); any vessel engaged in servicing, replenishing, or transferring cargo or
persons; or any vessel launching or recovering aircraft.
An alternative is Red over White over Red / Rudder Might be Dead. This
rhymes, but isn't quite accurate (a vessel with a truly dead rudder is Not Under
Command, Red over Red).
Stern Lights
Boats can also show stern lights to help identify them. These are only visible when you
are behind the boat. Some stern light combinations include:
Yellow over Yellow
A pushy inland fellow
This refers to the stern lights of a tug pushing a barge, under the inland rules only.
Yellow over White
My towline is tight
This refers to the stern lights of a tug towing astern.
Control Lights
Lights are also used to control passage through bridges and locks. So far, I only have
information for the European lock system, submitted by Ray Battersby. More will be
added as time and knowledge permit.
European (International) Harbor Traffic Control Signal Lights
This entire section was written and submitted by Ray Battersby.
Traffic-Light control signals are commonplace at the entrances to European ports. These
are generally of the form, Red, White (Yellow) and Green, vertically arranged and often
with other lamps in parallel. Because of the need to identify inbound and outbound
traffic, they don't use a simple Red = Stop, White (yellow) = Prepare to Move and Green
= Go (as for road traffic - that would be too simple and too easy to remember!) but a
combination.
However, by studying the Silk Cut Almanac, I have found that the following rules apply:
·
If the top lamp is showing RED irrespective of any other lamp that may be shining, you must
STOP and wait for the lights signals to change.
·
If the bottom lamp is shining GREEN irrespective of any other lamp that may be showing, then
you can GO.
·
If the middle lamp is showing WHITE (sometimes YELLOW), you must call Harbor Control on
VHF to ask permission before making a move.
NOTE: Although the above matches the official interpretation in terms of your own
rights of passage, using this abbreviated interpretation, a sharp lookout for other shipping
movements (especially from the opposite direction and from astern) is strongly advised.
Buoyage
There are two buoyage systems used in the world, named "A" and "B". Buoyage system
"A" is used in Europe, Asia, and Australia, with the exception of Japan, Korea, and the
Philippines. System "B" is used elsewhere, notably including all of the Americas. The
two systems use opposite color codes.
In both systems, the buoys also have coded shapes, called cans and nuns. A can is a
simple cylinder, like an oil can. A nun is conical, with the name being reminiscent of the
pointed hats worn by some orders of nuns. In both systems, cans appear on the left when
returning from sea to port, nuns on the right.
Buoyage Numbering
In both systems, green buoys are given odd numbers and red buoys are even. The
numbering starts at "1" at the mouth of the harbor or river, and increases from there.
The following two mnemonics may help remember the numbering scheme in the IALA
"B" system:
Demods
Buoy numbers DEcrease MOving DownStream.
You'll never see a nun 69
Nun (cone-shaped) buoys always have an even number.
Buoyage System "A"
The mnemonics given below are for buoyage system "A." Be sure to learn the right
mnemonics for your area!
Barrels to Port
In IALA "A," red-colored buoys are cans, which are shaped like barrels. A sailor returning from a
long trip looks forward to a barrel of port, so when coming into port, keep your port side closest to
the red barrel and you will be on the way to the nearest tavern.
Bleeding Heart
In IALA "A," red-colored buoys are kept to the side of your heart (left) when returning to port..
Buoyage System "B"
The mnemonics given below are for buoyage system "B." Be sure to learn the right
mnemonics for your area!
Red Right Returning
In IALA "B," red-colored buoys are nuns, which are kept to the right (starboard) side of the boat
when returning from the ocean to port. There is a detailed convention for defining exactly what
"returning" means in ambiguous situations (i.e., on canals and rivers), which will not be repeated
here.
Green Going Out The complement to "Red right returning," indicating that green buoys are left to
starboard when you are heading out to sea.
Even Red Left Port
The image is of a day so perfect that even the old red-headed sailor left his rocking chair to go to
sea, where he belongs (not that boring old port). This mnemonic has the advantage that it also
serves for the colors of running lights, for remembering that port is the left side of the boat, and for
recalling that red markers are even-numbered.
Sound Signals
There are many sound signals used in situations of limited visibility (i.e., fog), and when
two ships need to agree on the maneuvers necessary to avoid collisions (see the right-ofway rules below).
For collision avoidance, there are two systems. On inland waterways,
intention/agreement signals are used. On international (offshore) waters, actual rudder
actions are signaled. Fortunately, although at first glance the two systems differ, both
actually use the same effective meanings for signals. So all you have to remember is that
on an inland waterway, if somebody toots at you, you need to agree by repeating the
same pattern back at them, and if you toot, don't change course until you get agreement.
If you disagree, give the danger signal. Inland uses intention/agreement, offshore
signals rudder operations.
In sound signals, a short blast has a duration of about 1 second; a prolonged blast is 4-6
seconds.
When you are approaching another boat head-on (more or less), the first two mnemonics
below give the same information: turning to port will cause the other boat to pass on your
starboard side. This simplifies things: since both mnemonics refer to a double blast, you
can just memorize that fact, and know that the other direction is the single-blast case.
Note: If you are exactly head-on, or very nearly so, the COLREGS prefer that you turn to
starboard (single blast).
Port Rudder Action
Blast twice short,
Turn to port
Leaving a Boat on Your Starboard Side
Double blast,
Starboard pass
A double blast always means that you are turning (COLREGS) or will turn
(inland waters) to port. This means that you will pass the other boat on your
starboard side.
Backing Down
Three in turn,
Power astern
This indicates a boat that is slowing or stopping to avoid risk of collision.
Danger Signal
Blast quick five
To stay alive
This is the danger signal, to be given if you think there is confusion or imminent
danger of a collision.
Navigational Formulas
Navigation often requires relatively complicated arithmetic. The most common is
compass corrections: converting between true directions and a compass reading.
Timid Virgins Make Dull Company at Weddings
(Or "Add Whiskey.") This is the formula for converting true directions or courses to compass
readings: True plus Variation equals Magnetic heading. Beyond that, add the Deviation to get the
Compass heading. In all of these corrections, "at weddings" means Add Westerly variations and
deviations as part of the calculation (and, by implication, subtract easterly ones).
Can Dead Men Vote Twice at Elections?
This is the formula for converting compass headings back to true ones: Compass plus Deviation
equals Magnetic heading. Beyond that, add the Variation to get the True heading. In all of these
corrections, "at elections" means Add Easterly deviations and variations as part of the calculation
(and, by implication, subtract westerly ones).
Charter Boaters Detest Returning
This refers to the common mnemonic for predicting a collision: CBDR, for "Constant Bearing,
Decreasing Range." If the bearing to another vessel does not change, and the range is getting less,
you are going to bump. Note that this refers to the true or magnetic bearing, not the relative value.
Submitted by Steven Hodgson.
Right-of-Way Rules
The rules for who has the right of way are complex. The basic rule, of course, is General
Responsibility: notwithstanding any other rule, you're not supposed to run into other
people or things. That ought to be obvious.
For recreational boaters, a commonly-observed practical corollary is "tonnage has the
right of way": stay out of the way of big boats, because even if you're technically right,
you're going to be the loser in a collision.
The mnemonic below doesn't cover the situation where two similar boats are approaching
(nearly) head-on. In that case, it is preferred that you alter course to starboard, so that you
pass port-to-port (red to red, so that both are the give-way vessel). "Stay to the right and
you'll be right," but the general-responsibility rule still overrides everything else.
This mnemonic gives the "order of priority," with the most important first. To use it, find
yourself and the other boat on the list. The boat which comes first has the right of way,
and is the stand-on vessel. If you both fall in the same category, then either the category
itself tells you what to do (e.g., sailboats beat powerboats), or you must continue down
the list. The mnemonic is "Generally, anchoring our red tugboat diligently minimizes
surge loads." It is interpreted as follows:
Generally,
General responsibility. Above all else, don't have a collision. "I had the right of way" isn't a
defense if there was something you could have done to avoid the other boat.
anchoring
Anchored. Anchored, stopped, or moored boats must be avoided by all other vessels.
our
Overtaken. Boats being overtaken have the right of way over the overtaking vessel. (This is true
even if the slower boat is power and the faster boat is sail.)
red
Restricted maneuverability. Boats with restricted maneuverability, whether due to fishing, draft,
length, towing, or other causes, have the right of way over vessels not so restricted.
tugboat
Traffic separation. Vessels participating in a traffic-separation scheme have the right of way over
non-participating vessels. (If you must cross a traffic lane, try to do so at right angles.)
diligently
Downriver. On certain inland waters, powerboats proceeding downriver have the right of way
over upriver and crossing vessels.
minimizes
Man-powered beats sail beats motorboat beats seaplane. Human-powered boats (canoes and
rowboats) have the right of way over sailboats, which in turn have the right of way over
powerboats, and even they have the right of way over seaplanes.
surge
Starboard boat or starboard tack wins. This actually represents two rules, depending on whether
the meeting boats are both sail or both power. (If one is sail and one is power, the rule above
applies.) For power boats, the boat approaching from starboard has the right of way. For sailboats,
the boat that is on starboard tack has the right of way, regardless of from where it is approaching.
loads.
Leeward boat wins. When two sailboats meet on the same tack, the leeward boat has the right of
way over the windward boat.
"Nuclear restrictions constrain fishing and sailing, people say." It is interpreted as
follows:
Nuclear
Not Under Command. ("NUC" for "nuclear"). A vessel that is "not under command" in the
technical sense has the right of way. This refers to anchored or unoccupied vessels as well as those
that have lost the ability to maneuver (e.g., through loss of power or their rudder).
restrictions
Restricted maneuverability. Boats with restricted maneuverability, whether due to fishing, draft,
length, towing, or other causes, have the right of way over vessels not so restricted. (Note: Rod
McFadden has pointed out that while it makes sense for NUC boats to have the right of way over
those with restricted ability to maneuver, this is not explicitly mentioned in the COLREGS. He
comments, "I've been unable to find any case where a NUC/RAM collision occurred; it's safe to
say that if such a collision ever does occur, the Admiralty Bar will dine well for quite some time!")
constrain
Constrained by draft. Boats constrained to a narrow channel by their draft have the right of way.
(This is really a special case of restricted maneuverability).
fishing and
Fishing vessels. Vessels engaged in fishing (this means towing nets, etc., not people with a pole
off the back end) have the right of way. (Again, this is a special case of restricted
maneuverability).
sailing
Sailing vessel underway. Sailboats have the right of way over powerboats.
people
Power-driven vessel underway. Powerboats are near the bottom, but have right of way over:
say.
Seaplanes. Seaplanes must avoid everybody else.
<>Weather
There are lots of weather mnemonics to help you predict and analyze the weather.
Unfortunately, my best source at the moment is copyrighted (Reed's Nautical
Companion)
WARNING: Remember that most of these weather rhymes are rules of thumb, collected
over the centuries before we had supercomputers to help with weather foreguessing
(oops, forecasting). They are useful guides, but as in all areas of weather, there are no
certainties. Don't complain to me if they are less than 100% accurate.
· When the wind is at your back, the low is on your left. A formula for finding the center of a
weather system. This works only for the Northern Hemisphere; in the South, it's reversed.
Combined with a feeling for the direction weather moves, you can use this to make forecasts.
· Red sky at morning,
Sailors take warning.
Red sky at night,
Sailor's delight.
One of many classics. I learned this when I was a kid. I don't recall the mechanisms that make it
true, but a colorful dawn means bad weather, while a colorful sunset means that tomorrow will
probably be great sailing. Here's to red sunsets!
Reading the Color of the Bottom
Ways to guess the depth, based on water color. This is useful in the Caribbean, among
other places. The mnemonic goes from shallowest to deepest.
Brown brown, run aground,
White white, you might,
Green green, nice and clean,
Blue blue, run right through.
Chart Scale
I don't think anybody has any trouble picking a chart of the appropriate scale out of a
pile, since it's pretty obvious whether it covers just a harbor or the whole ocean. But a lot
of us have trouble with naming the damned things. Small scale, small detail; large
scale, large detail. So a large-scale chart is the one you'd ask for if you needed to enter a
harbor.
By the way, The Practical Pilot is the best book I've ever read on the subject of pleasureboat navigation. Where Dutton's has advice on steering a battleship or tanker through a
narrow channel (fascinating, but not something I ever expect to do), Eyges shows you
how to tell whether that's one island or two on the horizon. My favorite coastalnavigation book!
Boat Parts
The most basic terms in boating are those used to describe parts and directions on the
boat. Most of these don't have or need mnemonics. (Do you really want to learn 50-odd
different little rhymes just so you remember that the back of the boat is called the stern?)
But a few have some handy mnemonics.
General Boat Parts
Port
The left-hand side of the boat when facing forward. Many people remember that "port and left
both have four letters." Others use the mnemonic "I wonder if there's any red port wine left,"
which is nice because it gets the color of the light into the mnemonic.
A third optionis Red Left Port. The image is of a red-headed sailor going to sea,
where he belongs (not some nasty old port). This mnemonic has the advantage
that it also serves for remembering the colors of running lights and the codes for
buoyage system "B".
The name "port" derives from the fact that steering was originally done from the
right-hand side of the boat (see starboard, so the other side was put to the dock or
"port".
Starboard
The right-hand side of the boat when facing forward. The easiest way to remember this is to learn
where port is, and then recall that starboard is the opposite of port.
Incidentally, the word starboard comes from steerboard, because originally the
rudder was just a board held on the side of the boat, and most steersmen were
right-handed.
Forward
The direction towards the front of the boat.
Aft
The direction towards the back of the boat.
Bow
The forward end of the boat, usually the pointy end.
Stern
The aft end of the boat, usually the blunt end.
Shackle
A handy device for connecting things together. There are many types, but most consist of a "U" of
metal, together with a removable metal piece that closes the top of the "U" to make an "O". You
pull out the moving part, stick it through or around something, and fasten the whole thing together
to make it hold. Often used to attach sails to things and things to sails.
Sailboat Parts
Boom
A spar used to give shape to the bottom of any sail. If you don't watch out, it'll hit you in the
head, and you'll hear a loud boom.
Tack
The forwardmost, lowest part of a triangular sail. Just remember that the tack is where the sail is
tacked (attached) to the boat, usually by some sort of shackle. Not to be confused with the other
meaning of the word, which has to do with the relationship of the sailboat to the wind.
Clew
The aftmost, lowest part of a triangular sail. Expert sailors make all sorts of adjustments to a sail,
but beginners can adjust the clew to catch the wind even if they don't have a clue about the finer
points of sail trim.
Luff
The leading (forward) part of a sail, the part closest to the wind. If you adjust the sail improperly,
it will flap, which is called luffing, and the luff is the part which luffs first. (Got that?)
Leech
The trailing (aft) part of a sail, the part where the wind exits. When the sail is adjusted properly,
the wind will cling to the aft edge like a leech.
"leech" is a corruption of "lee edge" (say it fast).
Spar
Any structural member that supports a sail or helps to maintain a sail's shape (e.g., the mast or the
boom).
Mast
A vertical spar. Most modern sailboats have a single mast which supports two sails, but many
boats have two or more masts.