Regiment of Artillery'. A 2:3 rectangular flag, horizontally divided red-Navy blue. Red and blue represent the flash and the smoke of the gun according to gunners' folklore. In fact, red has been common to all combat arms (infantry, armour and artillery). The blue was taken from the ribbon of the 'Star of India' which had been incorporated in the artillery crest. The original colour was light blue but since a similar colour was adopted by the Corps of Signals, it was changed to Navy blue to avoid confusion.
http://www.crwflags.com/fotw/flags/in^armc.html
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