International signal flag banner

International Signal Flag
and Pennant Alphabet

Long before Radio was invented, boats could communicate by displaying flags.

Some flags stand for letters or numbers. Others represent words. Still others are repeat flags. Repeat flags are a way of indicating that a letter is repeated without having to stock many copies of the flag.

Most people have seen divers flags. These indicate when a diver is underwater and warns boats to stay away. Other flags might indicate quarantine or warn of other dangers.

Flags are often used in combination with others and this provides an extensive vocabulary. Ships carry a manual that help remind the seamen of the proper use of signaling flags.

Most flags have several meanings depending on circumstances and what other flags are displayed with it. Besides being a letter of the alphabet, a flag can communicate a message, such as a red and white signal flag means H, but also "I have a pilot on board".

Boat racers are familiar with various combinations of flags indicating starts, delays or shortened courses.

Most boat clubs will have their own flag or burgee.

When a boat is dressed up for a special occasion, it will sometimes display signal flags.The Canadian Navy has a Manual of Ceremony that gives the order of ceremonial flag displays.

gin pennant is an invitation to drinks

The Signal flags have a international meaning but some countries have added additional messages to the flags. The UK, Canada and likely most other countries that drink, have an unofficial Gin Pennant. When raised this is an invitation to officers for a celebration.

Signal Flags

Character Telephony Phonetic
flag a A -Alfa AL-FAH "I have a diver down; keep well clear at slow speed" The ALFA flag is a navigational signal intended to protect the vessel from collision.
With three numerals, azimuth or bearing.
flag b B -Bravo BRAH-VOH "I am taking in, or discharging, or carrying dangerous goods." (Originally used by the Royal Navy specifically for military explosives.)
flag c C -Charlie CHAR-LEE "Affirmative"
With three numerals, course in degrees magnetic.
flag d D -Delta DELL-TAH "Keep clear of me; I am maneuvering with difficulty"
With two, four, or six numerals, date.
flag e E -Echo ECK-OH "I am altering my course to starboard"
Crew at meals
flag f F -Foxtrot FOKS-TROT "I am disabled; communicate with me"
(When flown from an aircraft carrier; Warning; flight operations underway.
flag g G -Golf GOLF "I require a pilot"
When made by fishing vessels operating in proximity of the fishing grounds it means: "I am hauling nets."
With four or five numerals, longitude. (The last two numerals denote minutes and the rest degrees.)
flag h H -Hotel HOH-TEL "I have a pilot on board"
flag i I -India IN-DEE-AH "I am altering my course to port"
flag j J -Juliet JEW-LEE-ETT "I am on fire and have dangerous cargo on board: keep well clear of me"
or: I am leaking dangerous cargo
flag k K -Kilo KEY-LOH "I wish to communicate with you."
With one numeral, "I wish to communicate with you by..."; 1) Morse signalling by hand-flags or arms; 2) Loud hailer (megaphone); 3) Morse signalling lamp; 4) Sound signals.
flag l L -Lima LEE-MAH In harbour: "The ship is quarantined."
At sea: "You should stop your vessel instantly."
With four numerals, latitude. (The first two denote degrees and the rest minutes.)
flag m M -Mike MIKE "My vessel is stopped and making no way through the water."
flag n N -November NO-VEM-BER Negative
N and C together is used as a distress signal, (no and yes)
flag o O -Oscar OS-CAH "Man overboard." (often attached to the man overboard pole on boats).
With a sinister hoist, the semaphore flag.
flag p P -Papa PAH-PAH The Blue Peter.In harbour: All persons should report on board as the vessel is about to proceed to sea.
At sea: It may be used by fishing vessels to mean: "My nets have come fast upon an obstruction."
flag q Q -Quebec KEH-BECK "My vessel is 'healthy' and I request free pratique."
Pratique is the license given to a ship to enter port on assurance from the captain to the authorities, that she is free from contagious disease. The clearance granted is referred to as Free Pratique.
flag r R -Romeo ROW-ME-OH "The way is off my ship."
With one or more numerals, distance (range) in nautical miles.
flag s S -Sierra SEE-AIR-RAH "I am operating astern propulsion."
With one or more numerals, speed in knots.
flag t T -Tango TANG-GO "Keep clear of me; I am engaged in pair trawling."
With four numerals, local time. (The first two denote hours and the rest minutes.)
flag u U -Uniform YOU-NEE-FORM "You are running into danger."
flag v V -Victor VIK-TAH "I require assistance."
With one or more numerals, speed in kilometres per hour.
flag w W -Wiskey WISS-KEY "I require medical assistance."
flag x X -Xray ECKS-RAY "Stop carrying out your intentions and watch for my signals."
flag y Y -Yankee YANG-KEY "I am dragging my anchor."
flag z Z -Zulu ZOO-LOO "I require a tug."
When made by fishing vessels operating in close proximity on the fishing grounds it means: "I am shooting nets."
With one or more numerals, time (UTC). (The first two denote hours and the rest minutes.)
flag 1 1 -One WUN No International meaning
Navy Numeral 1
flag 2 2 -Two TOO No International meaning
Navy Numeral 2
flag 3 3 -Three TREE No International meaning
Navy Numeral 3
flag 4 4 -Four FOW-ER No International meaning
Navy Numeral 4
flag 5 5 -Five FIFE No International meaning
Navy Numeral 5
flag 6 6 -Six SIX No International meaning
Navy Numeral 6
flag 7 7 -Seven SEV-EN No International meaning
Navy Numeral 7
flag 8 8 -Eight AIT No International meaning
Navy Numeral 8
flag 9 9 -Nine NIN-ER No International meaning
Navy Numeral 9
flag 0 0 -Zero ZEE-RO No International meaning
Navy Numeral 0
pennant 1 1 -One WUN Numeral one (International) These is the numerals used by merchantmen
Pennant one (Navy)
pennant 2 2 -Two TOO Numeral two (International)
Pennant two (Navy)
pennant 3 3 -Three TREE Numeral three (International)
Pennant three (Navy)
pennant 4 4 -Four FOW-ER Numeral four (International)
Pennant four (Navy)
pennant 5 5 -Five FIFE Numeral five (International)
Pennant five (Navy)
pennant 6 6 -Six SIX Numeral six (International)
Pennant six (Navy)
pennant 7 7 -Seven SEV-EN Numeral seven (International)
Pennant seven (Navy)
pennant 8 8 -Eight AIT Numeral eight (International)
Pennant eight (Navy)
pennant 9 9 -Nine NIN-ER Numeral nine (International)
Pennant nine (Navy)
pennant 0 0 -Zero ZEE-RO Numeral zero (International)
Pennant zero (Navy)
first substitute First Substitute   Substitutes (or more accurately repeats) the first flag in the row of flags. This is a way of adding more of the same letters without having many sets of flags. Like the blank tile in Scrabble.
Also absence of flag officer.
General Recall in a sailing regatta
second substitute Second substitute   Substitutes for the second flag in the hoist. In other words when the second substitute flag appears, it represents the second letter in the row of flags.
third substitute Third substitute   Substitutes for the third flag in the hoist. It represents a repeat of the third letter in the row.
fourth substitute Fourth Substitute   Adds another copy of the fourth flag in the hoist.
code answer Code Answer   Message is understood. Also, numeric decimal point. (International)
Flag that follows is from the International Code of Signals. (US Navy)
small craft warning Small Craft Warning   Small craft warning: Sustained wind speeds in the range of 20 to 33 knots inclusive (Atmospheric Environment Service, Environment Canada) This is in the combined ranges of forces 6 and 7 on the Beaufort scale.
gale warning Gale warning   Approximately 34 to 47 knots
storm warning flag Storm Warning   Between 48 knots and 63 knots.
hurricane flag Hurricane Warning   Sustained winds of 64 knots, or higher is expected.
diving flag Diving Flag Alpha flag is the International flag for diving. Used to show that there is a diver below. The red and white divers flag is mainly used in North America and other countries (Italy) while internationally the A flag is more common.
The red and white flag often is used as a shop sign to indicate where diving goods and services are offered. Although widely recognized the red and white flag is not a legal requirement although it is permitted. The A flag is a legal requirement.
The Alfa flag is primarily intended to protect ships from collision, the diver-down flag is primarily intended to protect divers.

I try to be accurate and check my information, but mistakes happen.

email me if you find mistakes, I'll fix them and we'll all benefit: Christine