Maritime flags are an important way of communication out at sea. They require no means of verbal communication and make a message clear for all vessels within eyesight or even beyond when read through binoculars. Anyone in charge of a vessel (even the smallest, such as dinghies) needs to be able to at least identify flags A, B, D and O as well as the combination NC.
INTERNATIONAL CODE FLAGS
Alfa

Diver in the water – keep clear
Bravo

Explosives or other dangerous goods are been taken on or discharged.
Charlie

YES
Delta

Maneuvering with difficulty – keep clear
Echo

Altering course to STARBOARD
Foxtrot

Disabled – communication requested
Golf

Pilot required
Hotel

Pilot on board
India

Altering course to PORT
Juliett

On fire and carry dangerous cargo – keep clear
Kilo

Communication requested
Lima

Stop immediately
Mike

Vessel stopped, – unable to make way
November

NO
Oscar

Man overboard
Papa

All aboard! – Vessel proceeding to sea
Quebec

Requesting clearance into port – my vessel is healthy
Romeo

[None]
Sierra

Moving astern
Tango

Engaged in pair trawling – keep clear
Uniform

You are heading into danger
Victor

Assistance required
Whiskey

Medical assistance required
Xray

Stop with your intentions and wait my for signal
Yankee

Dragging anchor
Zulu

Tugging required
NUMERAL PENNANTS
1

2

3

4

5

6

7

8

9

0

SUBSTITUTE PENNANTS
1st
Substitute

2nd
Substitute

3rd
Substitute

Answering Pennant

COMMON FLAG COMBINATIONS
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