The USS WESTCHESTER COUNTY (LST 1167) was a Terrebone Parish class LST, laid down on 11 January 1952 at the Christy Corporation shipyard in Sturgeon Bay, Wisconsin. Launched on 18 April 1953, she was named for a southeastern New York county. The ship has a waterline length of 384 feet in length and a beam of 56-1/2 feet, displacing 2,590 tons light and 5,800 tons loaded. Although her maximum draft was 17 feet, she can beach herself for amphibious landings. Her normal crew was 153 sailors, and she could transport several hundred Marines. She was armed with three twin 3"/50 caliber MK33 rapid fire naval guns.
After fitting out and commissioning, WESTCHESTER COUNTY joined the fleet in 1954. In 1958 she transfered to the Pacific Fleet, homeported at Yokosuka, Japan. Routine operations were conducted throughout the western Pacific until March 1965, when she provided sealift for Marines going into Danang. In April she participated in the amphibious landing at Chu Lai. She continued to serve in transport, amphibious assault, and "mother ship" roles for the next three years.
WESTCHESTER COUNTY resumed duty with the Mobile Riverine Forces on 22 September 1968. On 1 November she was anchored in the My Tho River about 40 miles upstream from Vung Tau with other ships of Mobile Riverine Group Alpha, preparing to support Operation CORONADO IX. In addition to her crew and embarked soldiers (from 3/60 Infantry and 3/34 Artillery), she had over 10,000 rounds of 105mm and 155mm artillery ammo and large quantities of other explosives on her tank deck. There were five Army helicopters on the main deck.
A Viet Cong demolitions team managed to attach two mines to her hull about midship on the starboard side. When the two underwater explosions ripped WESTCHESTER COUNTY, 25 men were killed and 27 wounded. The day following the explosion, the entire Mobile Riverine Force moved from My Tho to Dong Tam.
After beaching at Dong Tam for temporary repairs, she returned to Yokusuka via Subic Bay. On 26 November, WESTCHESTER COUNTY went into dry dock at the United States Naval Ship Repair facility in Yokusuka where she remained until 5 February 1969. She returned to Vietnam on 10 March 1969.