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Code Breakers: Solve Puzzle Master Greg’s Secret Codes!

by | Apr 7, 2020 | Boating, eLearning, Fun, Grades 5-8, Grades K-4, Sailing | 1 comment

Signal Flag Communications

“Whensoever, and at all tymes the Admyrall doth shote of a pece of Ordnance, and set up his Banner of Council on Starrborde bottocke of his Shippe, everie shipps capten shall with spede go aborde the Admyrall to know his will.”

In the early days of sail, the use of signals to communicate between ships was primitive, as seen by one admiral's instructions to his fleet in 1530

Nautical flags were originally used for communications among comrades during military entanglements. What started as a limited communication system evolved over centuries into a comprehensive, internationally-recognized signaling system functional for military and non-military purposes. Recreational vessels also use nautical ship flags as well as code signal flags to identify themselves and to communicate with other ships.

There are various methods by which the flags can be used as signals:

  • A series of flags can spell out a message, each flag representing a letter.
  • Individual flags have specific and standard meanings; for example, diving support vessels raise the “A” flag indicating their inability to move from their current location because they have a diver underwater and to warn other vessels to keep clear to avoid endangering the diver(s) with their propellers.
  • One or more flags form a code word whose meaning can be looked up in a code book held by both parties. An example is the Popham numeric code used at the Battle of Trafalgar.
  • In yacht racing and dinghy racing, flags have other meanings; for example, the P flag is used as the “preparatory” flag to indicate an imminent start, and the S flag means “shortened course”
Signal flag for A

A - Alpha

I have a diver down; keep well clear at slow speed.

Signal flag for B

B - Bravo

I am taking in or discharging or carrying dangerous goods.

Signal flag for C

C - Charlie

Affirmative.

Signal flag for D

D - Delta

Keep clear of me; I am maneuvering with difficulty.

Signal flag for E

E -Echo

I am altering my course to starboard.

Signal flag for F

F - Foxtrot

I am disabled; communicate with me.

Signal flag for G

G - Golf

I require a pilot. When made by fishing vessels operating in close proximity on the fishing grounds it means: “I
am hauling nets”

Signal flag for H

H - Hotel

I have a pilot on board.

Signal flag for I

I - India

I am altering my course to port. (International)

Round the Ends Starting Rule (Sailing Regatta)

Signal flag for J

J - Juliet

I am on fire and have dangerous cargo; keep well clear of me, or I am leaking dangerous cargo.

Signal flag for K

K - Kilo

I wish to communicate with you.

Signal flag for L

L - Lima

You should stop your vessel immediately.
Come Within Hail or Follow Me (Sailing Regatta)

Signal flag for M

M - Mike

My vessel is stopped and making no way through the water..

Signal flag for N

N - November

No or negative.

Signal flag for O

O - Oscar

Man overboard.

Signal flag for P

P - Papa

In port: All personnel return to ship; the vessel is about to procede to sea.

At sea: It may be used by fishing vessels to mean: “My nets have come fast upon an obstruction”.

Signal flag for Q

Q - Quebec

Ship meets health regulations; request clearance into port

Signal flag for R

R - Romeo

Preparing to replenish (At sea).

Signal flag for S

S - Sierra

Moving astern. 

Signal flag for N

T - Tango

Keep clear, engaged in trawling. 

Signal flag for U

U - Uniform

You are running into danger. 

Signal flag for V

V - Victor

I require assistance 

Signal flag for W

W - Whiskey

I require medical assistance.

Signal flag for X

X - Xray

Stop carrying out your intentions and watch for my signals.

Signal flag for Y

Y - Yankee

I am dragging anchor. 

Signal flag for Z

Z - Zulu

I require a tug. 

The signal flag alphabet