Attached to III Marine Amphibious Force (III MAF), "Barry" was to provide naval gunfire coverage for the landing of 5,000 Marines on beaches north of Duc Pho in Quảng Ngãi Province on 28 January. Three battalions were landed, by helicopter and landing craft, in the largest combat assault since Inchon during the Korean War. Despite light rain and rough weather, the initial stage of Operation "Double Eagle" was completed in two days. As the Marines moved inland, searching for two suspected NVA regiments, they encountered scattered Viet Cong guerrillas instead. For the next five days, Barry, with the cruiser , provided fire missions for reconnaissance teams, conducted harassing fire at night, and commanded a South Vietnamese junk patrol designed to counter VC coastal infiltration.