Shield
Per fess Gules and Argent, in chief a mullet of the last, in base a pine tree Proper.
Crest
On a wreath of the colors Argent and Gules a phoenix Purpure ailleroned Or rising from flames Proper.
Motto
TERRAE PORTAM DEFENDAMUS (We Defend The Land Gate).
Shield
The 8th Regiment was organized under General Orders No. 8, 27 February 1924, on 30 June 1924, from the companies which composed the garrison of the Coast Defenses of Portland and Portsmouth. The coat of arms is that of the old Coast Defenses of Portland. The star has a dual significance. Its five points represent the five forts in the Coast Defenses; in addition it represents the Pole Star, those being the most northerly defenses in the country. It is set on a field of artillery red. The pine tree is the emblem of Maine, and is on a white field symbolic of the snows among which this particular pine (Pinus Rigidus) grows. The motto translates to "We Defend the Land Gate." "Terrae Portam" is also the Latin equivalent for Portland and "Defendamus" is the motto of the Coast Artillery Corps.
Crest
The crest is taken from the arms of the city of Portland which was thrice destroyed in war by burning, by the Indians in 1676, by the French in 1690 and by the English fleet in 1775, but each time it has risen phoenix like from its ashes.
The coat of arms was originally approved for the 8th Coast Artillery Regiment on 13 March 1924. It was amended to correct the translation of the motto on 31 March 1928. The insignia was redesignated for the 27th Antiaircraft Artillery Automatic Weapons Battalion on 14 January 1952.