Module 02

Semaphore

Two hand flags, eight arm positions, no equipment to fail. Semaphore is fast at close range and is still worked alongside during replenishment when radio silence is in force.

Lesson

How the positions are built

Each arm rests at one of eight points spaced 45 degrees apart, like the hours on a clock face. Every letter is a pair of those points, and no letter reuses a pair. All figures on this page are drawn as you would see them from the receiving ship — the signaller is facing you, so their right arm appears on your left. Read the angle of the arms, never the flags themselves.

Reference

The alphabet

Letter A
A
Letter B
B
Letter C
C
Letter D
D
Letter E
E
Letter F
F
Letter G
G
Letter H
H
Letter I
I
Letter J
J
Letter K
K
Letter L
L
Letter M
M
Letter N
N
Letter O
O
Letter P
P
Letter Q
Q
Letter R
R
Letter S
S
Letter T
T
Letter U
U
Letter V
V
Letter W
W
Letter X
X
Letter Y
Y
Letter Z
Z

Reference

Numerals

There are no separate figures for digits. Send the numerals sign, then use the letters below; the letters sign returns to plain text.

1

sent as A

2

sent as B

3

sent as C

4

sent as D

5

sent as E

6

sent as F

7

sent as G

8

sent as H

9

sent as I

0

sent as K

Reference

Special signals

Numerals sign

Numerals sign

Same position as J. Everything that follows is read as figures until the letters sign.

Letters sign (J)

Letters sign (J)

Same position as V. Cancels the numerals sign — resume reading letters.

Attention / call

Attention / call

Arms swept overhead repeatedly until the distant station answers.

Ready to receive

Ready to receive

Both arms held straight out — go ahead, I am reading you.

Rest / break

Rest / break

Arms down at the sides. Held briefly between words.

Erase / error

Erase / error

Eight successive E letters, the same convention as flashing light.