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Semaphore Flag Signaling System


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The Semaphore flag signaling system is an alphabet signaling system based on the waving of a pair of hand-held flags in a particular pattern.

flag image The flags are usually square, red and yellow, divided diagonally with the red portion in the upper hoist.

The flags are held, arms extended, in various positions representing each of the letters of the alphabet. The pattern resembles a clock face divided into eight positions: up, down, out, high, low, for each of the left and right hands (LH and RH) six letters require the hand to beTop Of This Page brought across the body so that both flags are on the same side.

flag image Flag positions in Semaphore

One way to visualize the semaphore alphabet is in terms of circles:

In the first circle, the letters A to C are made with the right arm, and E to G with the left, and D with either as convenient. In the second circle, the right arm is kept still at the letter A position and the left arm makes the movements; similarly in the remaining circles, the right arm remains fixed while the left arm moves. The arms are kept straight when changing fromTop Of This Page one position to another.

For another flag communication system, see the international maritime signal flags.


The Semaphore Alphabet

flag image A and 1 (LH down RH low)

flag image B and 2 (LH down; RH out)Top Of This Page

flag image C and 3 (LH down; RH high)

flag image D and 4 (LH down; RH up - or LH up; RH down)

flag image E and 5 (LH high; RH down)

flag image F and 6 (LH out; RH down)Top Of This Page

flag image G and 7 (LH low; RH down)

flag image H and 8 (LH across low; RH out)

flag image I and 9 (LH across low; RH up)

flag image J and 'alphabetic' (LH out ; RH up)Top Of This Page

flag image K and 0 zero (LH up; RH low)

flag image L (LH high; RH low)

flag image M (LH out; RH low)

flag image N (LH low; RH low)Top Of This Page

flag image O (LH across high; RH out)

flag image P (LH up; RH out)

flag image Q (LH high; RH out)

flag image R (LH out; RH out)Top Of This Page

flag image S (LH low; RH out)

flag image T (LH up; RH high)

flag image U (LH high; RH high)

flag image V (LH low; RH up)Top Of This Page

flag image W (LH out; RH across high)

flag image X (LH low; RH across high)

flag image Y (LH out; RH high)

flag image Z (LH out; RH across low)Top Of This Page


flag image Numerical sign (LH high; RH up)


flag image Annul sign (LH low; RH high)


flag image Error (LH and RH raised and lowered together)Top Of This Page

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