The Leahy-class were "double-end" guided missile Guided Missile Destroyer Leader [DLG], which as with other similar ships were reclassified as Guide Missile Cruisers [CG] on 30 June 1975. The class was given an AAW upgrade during the late-1960's and early 1970's, with Terrier launchers modified to fire Terrier or Standard SM-1ER missiles. The 3"/50 guns were replaced by 8 Harpoon missiles, the Terrier launchers were upgraded to fire the Standard SM-2ER missile, and 2 Phalanx CIWS were added. All were upgraded under the late-1980's New Threat Upgrade (NTU) program, which included combat system capability improvements to the ship's Air Search Radars (SPS-48E and SPS-49), Fire Control Radars (SPG-55B), and Combat Direction System (CDS). These improvements provided an accurate means of coordinating the engagment of multiple air targets with SM-2 Extended Range missiles.