UNITED STATES ARMY
COAST ARTILLERY BATTALIONS(ANTIAIRCRAFT) (MOBILE)
BATTERY GUIDONS • 1941On the eve of America's entry into the Second World War, the antiaircraft artillery units of the US Army were part of the Coast Artillery Corps. They were organized as two- or three-battalion regiments, and separate battalions. Those equipped with sufficient motor vehicles to move as a unit were designated (Mobile); those requiring additional vehicles to move as a unit were designated (Semimobile). There were also antiaircraft artillery batteries assigned to the fixed harbor defense forces.
Most of the separate battalions were 37mm gun/caliber .50 MG type, though some were 3in gun/searchlight types. The 3in and 37mm guns were scheduled to be replaced by the 90mm AA gun and the 40mm Bofors gun respectively.The gun battalions: had 12 x 3in AA guns and 12 x caliber .50 machine guns in three firing batteries plus a searchlight battery (15 x 60in searchlight); the automatic weapons battalions had 24 x 37mm guns in three batteries plus a battery with 12 x caliber .50 machine guns.On 7 December 1941, the 123rd Coast Artillery Battalion was assigned to the 34th Coast Artillery Brigade (Antiaircraft), First Army/Northeastern Defense Command.
