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.

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 Pronunciation	Meanings
	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.
	B -Bravo	BRAH-VOH	"I am taking in, or discharging, or carrying dangerous goods." (Originally used by the Royal Navy specifically for military explosives.)
	C -Charlie	CHAR-LEE	"Affirmative" With three numerals, course in degrees magnetic.
	D -Delta	DELL-TAH	"Keep clear of me; I am maneuvering with difficulty" With two, four, or six numerals, date.
	E -Echo	ECK-OH	"I am altering my course to starboard" Crew at meals
	F -Foxtrot	FOKS-TROT	"I am disabled; communicate with me" (When flown from an aircraft carrier; Warning; flight operations underway.
	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.)
	H -Hotel	HOH-TEL	"I have a pilot on board"
	I -India	IN-DEE-AH	"I am altering my course to port"
	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
	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.
	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.)
	M -Mike	MIKE	"My vessel is stopped and making no way through the water."
	N -November	NO-VEM-BER	Negative N and C together is used as a distress signal, (no and yes)
	O -Oscar	OS-CAH	"Man overboard." (often attached to the man overboard pole on boats). With a sinister hoist, the semaphore flag.
	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."
	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.
	R -Romeo	ROW-ME-OH	"The way is off my ship." With one or more numerals, distance (range) in nautical miles.
	S -Sierra	SEE-AIR-RAH	"I am operating astern propulsion." With one or more numerals, speed in knots.
	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.)
	U -Uniform	YOU-NEE-FORM	"You are running into danger."
	V -Victor	VIK-TAH	"I require assistance." With one or more numerals, speed in kilometres per hour.
	W -Wiskey	WISS-KEY	"I require medical assistance."
	X -Xray	ECKS-RAY	"Stop carrying out your intentions and watch for my signals."
	Y -Yankee	YANG-KEY	"I am dragging my anchor."
	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.)
	1 -One	WUN	No International meaning Navy Numeral 1
	2 -Two	TOO	No International meaning Navy Numeral 2
	3 -Three	TREE	No International meaning Navy Numeral 3
	4 -Four	FOW-ER	No International meaning Navy Numeral 4
	5 -Five	FIFE	No International meaning Navy Numeral 5
	6 -Six	SIX	No International meaning Navy Numeral 6
	7 -Seven	SEV-EN	No International meaning Navy Numeral 7
	8 -Eight	AIT	No International meaning Navy Numeral 8
	9 -Nine	NIN-ER	No International meaning Navy Numeral 9
	0 -Zero	ZEE-RO	No International meaning Navy Numeral 0
	1 -One	WUN	Numeral one (International) These is the numerals used by merchantmen Pennant one (Navy)
	2 -Two	TOO	Numeral two (International) Pennant two (Navy)
	3 -Three	TREE	Numeral three (International) Pennant three (Navy)
	4 -Four	FOW-ER	Numeral four (International) Pennant four (Navy)
	5 -Five	FIFE	Numeral five (International) Pennant five (Navy)
	6 -Six	SIX	Numeral six (International) Pennant six (Navy)
	7 -Seven	SEV-EN	Numeral seven (International) Pennant seven (Navy)
	8 -Eight	AIT	Numeral eight (International) Pennant eight (Navy)
	9 -Nine	NIN-ER	Numeral nine (International) Pennant nine (Navy)
	0 -Zero	ZEE-RO	Numeral zero (International) Pennant zero (Navy)
	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		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		Substitutes for the third flag in the hoist. It represents a repeat of the third letter in the row.
	Fourth Substitute		Adds another copy of the fourth flag in the hoist.
	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: 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		Approximately 34 to 47 knots
	Storm Warning		Between 48 knots and 63 knots.
	Hurricane Warning		Sustained winds of 64 knots, or higher is expected.
	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.