International Code of Signals (ICS) - Flag Guide
Signal flags are used at sea for communication between ships while maintaining radio silence. Navy Signalmen transmit messages by hoisting a flag or a series of flags on a halyard. When communicating with other vessels, the International Code of Signals (ICS) is used.
In ICS, individual flags can spell out short messages whereas a combination of flags can have a special meaning. The code / answer pennant precedes all signals in international code. Signal flags are sometimes also used to decorate ships during festivities.
All signal flags include one of three attachment methods:
1) Rope and toggle 2) Header and grommets 3) Brass snap and ring
There is a total of 40 flags in a set: 26 alphabet flags, 11 pennants (numeral flags) and 3 substitutes. Substitutes are utilized to repeat a previously used character without having to buy multiples of the same flag. The flags run from size 0 to size 14; the dimensions chosen are dependent on the height and length of the vessel, how much space is allocated for the signal flags, etc.
Signal flag size chart:
|Size 0||Size 2||Size 3||Size 7||Size 10||Size 14|
The 26 alphabet flags:
The 11 numeral and code / answer pennants:
The 3 substitutes:
Examples for using substitute flags to repeat a previously used character:
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