The 2nd Air Defense Artillery Regiment is an air defense artillery regiment of the United States Army, first formed in 1821 as a field artillery unit. Battery A-2nd ADAR THAAD (Battery A, 2nd Air Defense Artillery Regiment, Terminal High Altitude Area Defense) of the 11th Air Defense Artillery (ADA) Brigade successfully intercepted an Intermediate Range Ballistic Missile which was launched near Hawaii on 11 July 2017. The soldiers used the procedures of an actual combat scenario at the Pacific Spaceport on Kodiak Island, Alaska, and were not aware of the IRBM's launch time.