At sea, flags can be very important, often meaning the difference between life and death. Because of its importance the rules and regulations for flying flags at sea are strictly enforced.
A national flag flown at sea is known as an ensign and most ships usually fly its ensign along with the flag of the nation it is currently visiting (known as a courtesy flag). A ship sailing alone with only its ensign in foreign water, a foreign port or in sight of a foreign warship traditionally represents a willingness to fight. This old custom is still taken seriously by many naval and port authorities and is enforced in parts of the world by boarding, confiscation or other civil penalties.
Nautical flags are an international code system used for two ships to signal to each other or for a ship to signal to shore. They are also called signaling nautical flags. Using a group of different colored flags, shaped flags and markings each one has a different meaning. The flags can be used alone or in combination with another flag.
Nautical flags are made up of 26 square flags (which represent the letters of the alphabet) along with 10 numbered pendants; one answering pendant and three substitutes or repeaters. At sea, only a few flag colors are easily recognized, these are: red, blue, yellow, black, and white and they cannot be mixed indiscriminately. For easy recognition nautical flags are either red and white, yellow and blue, blue and white, black and white along with plain red, white and blue.
Nautical flags and the knowledge of their meanings are valuable at sea in case of danger or breakdowns in other communications systems such as radio.
- One-flag signals are urgent or common signals.
- Two-flag signals are used mostly for distress and maneuvering.
- Three-flag signals are for points of the compass, relative bearings, standard times, verbs, punctuation and also general code and decode signals.
- Four-flags are used for geographical signals, names of ships, bearings, etc.
- Five-flag signals are used to relate time and position.
- Six-flag signals are used to indicate north or south or east or west in latitude and longitude signals.
- Seven-flags are for longitude signals containing more than one hundred degrees.
There are also flags used in nautical racing which signal to the competitors what they are supposed to do.
International meanings for nautical flags:
A: Alpha - diver down; keep clear
B: Bravo - carrying dangerous cargo
C: Charlie - yes
D: Delta - keep clear
E: Echo - altering course to starboard
F: Foxtrot - I am disabled
G: Golf - I want a pilot
H: Hotel - a pilot on board
I: India - I am altering course to port
J: Juliet - vessel on fire keep clear
K: Kilo - I want to communicate with you
L: Lima - stop your vessel instantly
M: Mike -my vessel is stopped
N: November - no
O: Oscar - Man overboard
P: Papa - vessel is about to sail
Q: Quebec - I request free pratique
R: Romeo - reverse course
S: Sierra - engines are going astern
T: Tango - keep clear
U: Uniform - you are heading into danger
V: Victor - require assistance
W: Whiskey - require medical assistance
X: X-ray - stop your intention
Y: Yankee - am dragging anchor
Z: Zulu - I require a tug