Nicholas “The Chieftain” Moran from World of Tanks writes about the history of tank signal flags.
Tier I tanks used to come with “Signal Flags” as part of their basic radio system. Threads on the forum, reddit, etc. have asked, “Did WoT make this up? Did tankmen really use flags?”
Sure enough, the answer is ‘yes’ (in semaphore, as in the photo above). In a time when the “intercom system” could be as technical as kicking the driver to indicate which way you wanted to go, communications with the world outside the tank was even more difficult.
Just because tanks were coming standard with radios didn’t mean that signal flags would be obsolete. In early 1941, Armored Force was trying to come up with its own visual signals guide, and that March approved the signals as found in Field Manual 17-5:
“Disregard my movements:” Flag Stationary
“Do as I do:” Raise and lower flag repeatedly
“Assemble:” Wave flag in large circles
“Form extended column:” Wave flag from font to rear, as determined by direction in which signaller’s vehicle is facing
“Form extended line:” Wave flag from side to side, as determined by direction in which signaller’s vehicle is facing
“Form column:” “Extended Column” signal, followed immediately by “Assemble” signal
“Form line:” “Extended line” signal, followed immediately by “Assemble” signal