Marine Surveyors Lexicon

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Signal Pennants


International Code Flags and Pennants are used to signal between two ships or between ship and shore. Also called signaling flags, they are a set of flags of different colors, shapes and markings which used singly or in combination have different meanings. The flags include 26 square flags which depict the letters of the alphabet, ten numeral pendants, one answering pendant, and three substituters or repeaters.

Only a few colors can be readily distinguished at sea. These are: red, blue, yellow, black, and white; and these cannot be mixed indiscriminately. You will notice, for clarity, the flags shown are either red and white, yellow and blue, blue and white, or black and white; besides plain red, white, and blue.

One-flag signals are urgent or very common signals (see meanings below). 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.

Edge of a flag next to the pole or mast is termed the hoist; it's free end, the fly, and a short piece of line attached to lower end of hoist, or an extension thereto, as always provided on signal flags, the tack or tack-line. Flags of rectangular shape are called square flags. Those of triangular or tapering quadrilateral shape, pennants, and those having pointed corners at the fly (swallow-tailed) are called burgees.

A Alpha When hoisted singly means: "I have a diver down; keep well clear at slow speed."
B Bravo When hoisted singly means: "I am taking in, or discharging, or carrying dangerous goods."
C Charlie When hoisted singly means: "Yes, affirmative".
D Delta When hoisted singly means: "Keep clear of me, I am maneuvering with difficulty."
E Echo When hoisted singly means: "I am altering my course to starboard."
F Foxtrot When hoisted singly means: "I am disabled; communicate with me."
G Gulf When hoisted singly means: 'I require a pilot". When made by fishing vessels operating on the fishing grounds, it means: "I am hauling nets."
H Hotel When hoisted singly means: "I have a pilot on board."
I India When hoisted singly means: "I am altering my course to port." Also called the interrogatory flag.
J Juliet When hoisted singly means: "I am on fire and have dangerous cargo on board. Keep well clear of me."
K Kilo When hoisted singly means: "I wish to communicate with you."
L Lima When hoisted singly means: "You should stop your vessel instantly."
M Mike When hoisted singly means: "My vessel is stopped and making no way through the water." Not international but commonly used: Doctor on board
N November When hoisted singly means: "No." Also known as the negative flag.
O Oscar When hoisted singly means: "man overboard."
P Papa When hoisted singly in port, means: "All persons return to the ship which is ready to depart." Also known, particularly among the British, as the Blue Peter.
Q Quebec When flown singly the quarantine flag means: "My vessel is healthy and I request free pratique."
R Romeo
S Sierra When hoisted singly means: "My engines are going astern."
T Tango When hoisted singly means: "Keep clear of me, I am engaged in pair trawling." As a freeboard mark, it indicates the load line in the tropics. Not international but commonly used: Request for transportation (from club launch)
U Uniform When hoisted singly means: "You are running into danger."
V Victor When hoisted singly means: "I require assistance."
W Whiskey When hoisted singly means: "I require medical assistance."
X Xray When hoisted singly means: "Stop carrying out your intentions and watch for my signals."
Y Yankee When hoisted singly means: "I am dragging my anchor."
Z Zulu When hoisted singly means: "I require a tug."; when shown by a fishing vessel near the fishing grounds, means: "I am shooting nets."
0
1
2
3
4
5
6
7
8
9
0
First Repeater The First Repeater repeats the upper flag or pennant of a hoist. Now called a substitute in the NATO Navies.
Second Repeater A signal flag used to repeat another flag directly above it in a flag hoist.
Third Repeater A signal flag used to repeat another flag directly above it in a flag hoist.
Code and Answering Pennant The answering pennant is used as a decimal point when sending numeric data. Close up (top of mast), the receiving vessel indicates she understands the hoist. At the end of the signal it indicates that the message is complete. At dip(half masted), hoisted by the receiving vessel as each hoist of the transmitting ship is seen.


Some Useful Two Letter Signals:
AC
I am abandoning my vessel.
LO
I am not in my correct position: used by a light vessel.
RU
Keep clear of me; I am maneuvering with difficulty.
AN
I need a doctor.
NC
I am in distress and require immediate assistance.
SO
You should stop your vessel instantly.
BR
I require a helicopter.
PD
Your navigation lights are not visible.
UM
The Harbour is closed to traffic.
CD
I require immediate assistance.
PP

OR


OR


Keep well clear of me.
UP
Permission to enter Harbour is urgently requested. I have an emergency.
DV
I am drifting.
QD
I am going ahead.
CU
I am going to communicate with your station by means of the International code of signals.
EF
SOS/MAYDAY has been canceled.

I am going astern.
ZD1

Please report me to the Coast Guard, New York
FA
Will you give me my position?
QQ

OR


OR


I require health clearance.
ZD2

Please report me to Lloyds, London.
GW
Man overboard. Please take action to pick him up.
QU
Anchoring is prohibited.
ZL
Your signal has been received but not understood.
JL
You are running the risk of going aground.
QX
I request permission to anchor.
AE
I must abandon my vessel
CJ
Do you require assistance?
CN
I am unable to give assistance
JI
Are you aground?
JL
You are running the risk of going aground
JW
I have sprung a leak
KN
I cannot take you in tow
KN1

I cannot take you in tow but I will report you and ask for immediate assistance. Note, a numeral is added to general messages to provide variation in meaning, to ask or answer a question, or to supplement the basic message.
LN
Light (name follows) has been extinguished
LO
I am not in my correct position (To be used by a lightship)
LR
Bar is not dangerous
LS
Bar is dangerous
MF
Course to reach me is ...
MG
You should steer course ...
NC
I am in distress
NF
You are running into danger
NG
You are in a dangerous position
YZ
Indicates words which follow are in plain language. Use is optional if it is obvious the words are in plain language.