A - Alfa
Diver below - slow down and keep clear.
The swallowtail cut-out is the diver's fins.
Free micro-course
Learn maritime signal flags without staring at a wall chart
A free International Code of Signals course for Alfa to Zulu, numeral pennants, substitutes, NC distress, and live hoist practice. It is an independent revision aid, not an official navigation authority publication.
Diver down
Man overboard
Yellow flag
Phonetic names
Hoist reading
Shareable finale
Lesson 1
How signal flags work
Flags are an alphabet, but a hoist is read from top to bottom. The answering pennant turns a hoist into a conversation.
Build a flag
Layer 1/5
Q - Quebec
Healthy vessel requesting pratique.
Quebec is the plain yellow quarantine/pratique flag.
AP - Answering pennant
Ready, understood, or end of signal depending on its position.
The answering pennant is the conversation marker.
Quick practice check
Try a few questions before you move into the full module.
1. How do you read a signal-flag hoist?
2. What does the answering pennant help show?
3. Why are flags still useful?
Must-know hoists
Read more than one flag at once
Multi-flag hoists are read from top to bottom. NC is the core distress hoist learners should recognise before going afloat.
NC
I am in distress and require immediate assistance.
MAA
I request urgent medical advice.
AN
I need a doctor.
EL
Repeat the distress position.
GN
You should take off persons.
Generated quiz
Signal flag recognition
Question 1 of 100%
Which flag is Second substitute?
Hoist reader
Read the flags from top to bottom
Type the hoist letters or choose the meaning. Substitutes are expanded before the answer is checked.
Score 0/0
Hoist 1
Finale
Spell your name in signal flags
Type letters or numbers and the hoist updates live. Repeated letters use substitutes automatically, which is the rule most flag charts skip.
7/24 characters
COMPASS
Live flag chart
International Code of Signals flags
Every flag below is rendered from data, not an image file. Use the anchors for quick lookups such as Alfa, Oscar, Quebec, or NC.
A - Alfa
swallowtails
I have a diver down; keep well clear at slow speed.
B - Bravo
swallowtails
I am taking in or discharging or carrying dangerous goods.
C - Charlie
bands
Affirmative.
D - Delta
bands
Keep clear of me; I am manoeuvring with difficulty.
E - Echo
bands
I am altering my course to starboard.
F - Foxtrot
diamonds
I am disabled; communicate with me.
G - Golf
bands
I require a pilot. By fishing vessels near fishing grounds: I am hauling nets.
H - Hotel
halves
I have a pilot on board.
I - India
circles
I am altering my course to port.
J - Juliett
bands
I am on fire and have dangerous cargo on board: keep well clear of me. Or: I am leaking dangerous cargo.
K - Kilo
halves
I wish to communicate with you.
L - Lima
quarters
Stop immediately.
M - Mike
saltires
My vessel is stopped and making no way through the water.
N - November
checks
Negative.
O - Oscar
diagonals
Man overboard.
P - Papa
centre-squares
In harbour: All persons should report on board as the vessel is about to proceed to sea. At sea: my nets have come fast upon an obstruction.
Q - Quebec
solid
My vessel is healthy and I request free pratique.
R - Romeo
crosses
No ICS meaning as a single flag.
S - Sierra
centre-squares
I am operating astern propulsion.
T - Tango
bands
Keep clear of me. Fishing vessels: keep clear of me; I am engaged in pair trawling.
U - Uniform
quarters
You are running into danger.
V - Victor
saltires
I require assistance.
W - Whiskey
centre-squares
I require medical assistance.
X - Xray
crosses
Stop carrying out your intentions and watch for my signals.
Y - Yankee
diagonals
I am dragging my anchor.
Z - Zulu
diagonals
I require a tug. By fishing vessels near fishing grounds: I am shooting nets.
0 - Nadazero
numerals
Numeral pennant zero.
1 - Unaone
numerals
Numeral pennant one.
2 - Bissotwo
numerals
Numeral pennant two.
3 - Terrathree
numerals
Numeral pennant three.
4 - Kartefour
numerals
Numeral pennant four.
5 - Pantafive
numerals
Numeral pennant five.
6 - Soxisix
numerals
Numeral pennant six.
7 - Setteseven
numerals
Numeral pennant seven.
8 - Oktoeight
numerals
Numeral pennant eight.
9 - Novenine
numerals
Numeral pennant nine.
1st sub - First substitute
substitutes
Repeats the first flag of a hoist later within the same hoist.
2nd sub - Second substitute
substitutes
Repeats the second flag of a hoist later within the same hoist.
3rd sub - Third substitute
substitutes
Repeats the third flag of a hoist later within the same hoist.
AP - Answering pennant
answer
At the dip: ready to receive. Close up: message received and understood. Hauled down: signals end.