Flying international code flags or
signal flags while underway is an age-old nautical
tradition. Long before radio communication, flags
were hoisted to send messages to other mariners or
those ashore. Today, while ensign flags and
ornamental flags are common, only a handful of code
flags are usually found aboard recreational vessels.
For the most part, code flags are typically displayed
during parades and on special occasions. But these
universal signals of the sea continue to be practical
and useful nautical communicators.
Each letter of the alphabet has a
signal flag and there is a pennant for each number
from 0 to 9. There are also answering and repeater
flags available.
Signal flags vary in shape and
color … some are square while others are shaped
like typical pennants. The combination of flags
hoisted indicates specific nautical conditions or
navigational maneuvers.
For example, hoisting the "A"
(Alfa) flag signals that a diver is down and to keep
clear, while flying the "W" (Whiskey) flag indicates
that medical assistance is needed aboard.
International code flags can also
be used to respond to another vessel. For example, if
you see the "QX" flag combination flying it means the
boater is requesting permission to anchor. Your
response may be to raise the "QU" flags indicating
that anchoring is prohibited or the "ZL" which means
the other vessel's signal has been received but it
isn't understood.
Here are additional 2-Letter Flag
Codes:
AC - I am abandoning my vessel.
AN - A doctor is needed.
BR - A helicopter is needed.
CD - Immediate assistance is needed.
DV - I am drifting.
EF - SOS/MAYDAY is canceled.
FA - Will you give me my position?
GW - Man overboard ... please pick him up.
JL - You are running the risk of going aground.
LO - I am not in my correct position.
RU - Keep clear of me; I have a problem
maneuvering.
NC - I am in distress and require assistance.
SO - You should stop your vessel immediately.
PD - Your navigation lights are not visible.
UM - The harbor is closed.
PP - Keep well clear of me.
UP - Permission to enter harbor is urgently requested
(emergency).
QD - I am going ahead.
QT - I am going astern.
QQ - I require health clearance.
QU - Anchoring is prohibited.
QX - I request permission to anchor.
YU - I am going to communicate with your station by
means of the international code of signals.
ZL - Your signal has been received but not
understood.
While boating in the United States,
it is customary to fly the national "ensign" or
American flag, but if you cross into foreign waters
you should be prepared to display two other
flags.
The letter "Q" or quarantine flag
should be hoisted once in foreign waters. The flag
should be flown until you are cleared by customs. The
flag of the nation visited should replace the Q once
cleared by customs. This flag is called the "courtesy
flag." Both flags should be hoisted on the starboard
spreader or on the bow.
The National Ensign, of course, is
always the first flag hoisted. It is customary to
hoist the national symbol at 8 a.m. and fly it until
sunset, unless entering a port when it should be
flown at all times.
The ensign is also flown at the
highest point at the stern of the boat (if you have a
gaff-rigged vessel you can place it at the peak of
the raised gaff).
Nautical flags can be purchased
individually or in sets. Signal flag and pennant set
prices are determined by the size of the flags. For
example, a full set of 3-foot by 3-foot and 2-foot by
6-foot signal flags cost about $1,000. A 3-foot by
5-foot National Ensign, however, can be purchased for
about $30. Shops ashore and many online venues sell
nautical flags.
Nautical flags are an investment
worth protecting so that you can count on years of
use. Treating nautical flags wiith a quality
waterproofing agent will protect them from the
degrading effects of saltwater, dirt and mildew.
Here is a short list of
waterproofers available at some of the specialty
marine supply stores: