Nautical Flags and Their Meanings - Multiple Flags

Here are some examples of messages using more than one signal flag:

• One-flag signals are urgent or very common signals
• Two-flag signals are mostly distress and maneuvering signals
• Three-flag signals are for points of the compass, relative bearings, standard times, verbs, punctuation, also general code and decode signals
• Four-flags are used for geographical signals, names of ships, bearings, etc
• Five-flag signals are those relating to time and position
• Six-flag signals are used when necessary 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.

A complete manual, published by the Maritime Safety Office of the National Geospatial-Intelligence Agency, can be found here.

Flags below are shown horizontally, but are displayed vertically.

Multiple Flags Signal Codes

Code	Flags	Meanings
A+C		I am abandoning my vessel
A+E		I must abandon my vessel
A+F		I do not intend to abandon my vessel
A+G		You should abandon your vessel as quickly as possible
A+H		You should not abandon your vessel
A+L		I have a doctor on board
A+M		Have you a doctor?
A+N		I need a doctor
A+N+1		I need a doctor; I have severe burns
B+F		Aircraft is ditched in position indicated and requires immediate assistance
B+P		Aircraft is coming to participate in search
B+R		I require a helicopter urgently
C+B		I require immediate assistance
C+B+6		I require immediate assistance, I am on fire
C+J		Do you require assistance?
C+K		Assistance is not (or is no longer) required by me (or vessel indicated)
C+P		I am proceeding to your assistance
C+V		I am unable to give assistance
C+W		Boat/raft is on board
C+Z		You should make a lee for the boat(s)/raft(s)
D+D		Boats are not allowed to come alongside
D+V		I am drifting
D+X		I am sinking
E+D		Your distress signals are understood
E+F		SOS/Mayday has been canceled
E+L		Repeat the distress position
E+L+1		What is the position of vessel in distress?
E+P		I have lost sight of you
E+X		My position is doubtful
E+Y		I am confident as to my position
F+A		Will you give me my position?
F+E		I am proceeding to the position of accident at full speed
F+N		I have lost all contact with vessel
F+O		I will keep close to you
G+A		I cannot continue to search
G+B		You should stop search and return to base or continue your voyage
G+F		I have found vessel/aircraft in distress in lat... long...
G+M		I cannot save my vessel
G+N		You should take off persons
G+N+2		I will take off persons
G+O		I cannot take off persons
G+Q		I cannot proceed to the rescue owing to weather. You should do all you can.
G+W		Man overboard. Please take action to pick him up
G+Z		All persons saved
G+Z+1		All persons lost
H+M		Survivors are in bad condition. Medical assistance is urgently required
H+W		I have collided with surface craft
I+B+1		My vessel is seriously damaged
I+M		I request to be escorted until further notice
I+N		I require a diver
I+R		I am engaged in submarine survey work (underwater operations). Keep clear of me and go slow.
I+T		I am on fire
J+B		There is danger of explosion
J+G		I am aground; I am in dangerous situation
J+H		I am aground; I am not in danger
J+I		Are you aground?
J+L		You are running the risk of going aground
J+M		You are running the risk of going aground at low water
J+W		I have sprung a leak
K+F		I require a tug (or... (number) tugs)
K+K		Towing is impossible under present weather conditions
K+N		I cannot take you in tow
K+P		You should tow me to the nearest port or anchorage
L+I		I am increasing speed
L+J		I am reducing speed
L+N		Light (name follows) has been extinguished
L+O		I am not in my correct position (To be used by a lightship)
L+R		Bar is not dangerous
L+S		Bar is dangerous
L+X		The canal is clear
L+Y		The canal is not clear
L+Z		The channel/fairway is navigable
M+B		You should keep in the center of the channel/fairway
M+C		There is an uncharted obstruction in the channel/fairway. You should proceed with caution
M+F		Course to reach me is ...
M+G		You should steer course ...
M+O		I have struck a shoal or submerged object (lat... long...)
M+S		My vessel is a dangerous source of radiation
M+Y		It is dangerous to stop
N+A		Navigation is closed
N+C		I am in distress and require immediate assistance
N+D		Tsunami (phenomenal wave) is expected. You should take appropriate precautions
N+E		You should proceed with great caution
N+F		You are running into danger
N+G		You are in a dangerous position
N+O		Negative—"No" or "The significance of the previous group should be read in the negative"
N+T		What is your draft?
O+H		You should switch on your radar and keep radar watch
O+I		I have no radar
O+K		Acknowledging a correct repetition or "It is correct"
O+S		There is danger from mines in this area (or area indicated)
P+D		Your navigation lights are not visible
P+H		You should steer as indicated
P+H+1		You should steer towards me
P+K		I cannot steer without assistance
P+M		You should follow in my wake (or wake of vessel indicated)
P+O		You should pass ahead of me (or vessel indicated)
P+P		Keep well clear of me
P+S		You should not come any closer
Q+C		You should wait until high water
Q+C+1		You should wait until low water
Q+D		I am going ahead
Q+F		I cannot go ahead
Q+I		I am going astern
Q+K		I cannot go astern
Q+O		You should not come alongside
Q+Q		I require health clearance
Q+T		You should not anchor. You are going to foul my anchor
Q+U		Anchoring is prohibited
Q+X		I request permission to anchor
R+A		My anchor is foul
R+B		I am dragging my anchor
R+L		You should stop your engines immediately
R+M		My engines are stopped
R+P		Landing here is highly dangerous
R+S		No one is allowed on board
R+T		Stop carrying out your intentions and watch for my signals
R+U		Keep clear of me; I am maneuvering with difficulty
S+B		I am proceeding to the position of accident
S+C		I am underway
S+D		I am not ready to get underway
S+G		My present speed is... (number) knots
S+M		I am undergoing speed trials
S+O		You should stop or heave to
S+T		What is your cargo?
S+Z		Total number of persons on board is...
T+P		Fishing gear has fouled my propeller
T+V		Fishing in this area is prohibited
T+Z		Can you offer assistance?
U+H		Can you lead me into port?
U+L		All vessels should proceed to sea as soon as possible owing to danger in port
U+M		The harbor is closed to traffic
U+O		You must not enter harbor
U+P		Permission to enter harbor is urgently requested. I have an emergency
U+S+4		Nothing can be done until weather moderates
U+W		I wish you a pleasant voyage
V+L		Tropical storm (cyclone, hurricane, typhoon) is approaching. You should take appropriate precautions
W+E		Navigation channel is being kept open by icebreaker
W+W		What are the sea conditions in your area (or around lat... long...)?
X+P		I am (or vessel indicated is) stopped in thick fog
X+R		Weather is good
X+R+1		Weather is bad
Y+C		Wind force expected is Beaufort Scale... (numerals 0-12)
Y+K		I am unable to answer your question
Y+N		Cancel my last signal/message
Y+U		I am going to communicate with your station by means of the International code of signals
Y+Y		I wish to communicate by VHF radiotelephony on channel indicated
Y+Z		I'm going to spell a word with my next set of flags
Z+E		You should come within visual signal distance
Z+H		Exercise had been completed
Z+L		Your signal has been received but not understood
Z+S		My vessel is "healthy" and I request free pratique
Z+W		I require Port Medical Officer
Medical Signal Codes (Three-letter signals beginning with "M" are the Medical Signal Codes. Just a few shown here... many more are listed in the International Code of Signals Manual)
M+A+A		I request urgent medical advice
M+A+B		I request you to make rendezvous in position indicated
M+A+C		I request you to arrange hospital admission
M+A+D		I am . . . (indicate number) hours from the nearest port
M+A+O		General condition of the patient is good
M+A+P		General condition of the patient is serious