USS Columbia (SSN-771) is the 21st flight III, or Improved (688i) attack submarine of the United States Navy. Commissioned in 1995, the submarine is assigned to Submarine Squadron 7 and homeported in Joint Base Pearl Harbor-Hickam. Columbia is the eighth U.S. warship to bear the name, though the first to be named for three cities: Columbia, Illinois, Columbia, Missouri and Columbia, South Carolina. The contract to build Columbia was awarded to the Electric Boat Division of General Dynamics Corporation in Groton, Connecticut, on 14 December 1988 and her keel was laid down on 21 April 1993. She was the 33rd Los Angeles-class boat built by Electric Boat, and was launched on 24 September 1994 with the slide down a 1,300-foot wooden ramp, the last American submarine to do so, giving her the title of "The Last Slider". Columbia was sponsored by Hillary Clinton, and commissioned on 9 October 1995. Service history From March to May 1999, Columbia operated off the California coast, participating in exercises and making port visits. In 2011, the submarine deployed to the Western Pacific Ocean (WestPac), including a port visit at Yokosuka, Japan. In May 2014, Columbia left on another western Pacific deployment, again stopping in Yokosuka on 5 November and returning to her homeport of Joint Base Pearl Harbor-Hickam on 21 November. In 2016, Columbia deployed on a six-month patrol in the western Pacific, making port visits at Yokosuka and Sasebo, Japan, and Guam. In 2018, the sub made another WestPac deployment, stopping at Yokosuka in May. In October 2018, the submarine began a mid-life overhaul at Pearl Harbor Naval Shipyard and Intermediate Maintenance Facility. She left dry dock on 16 July 2020 and returned to the Navy on 17 May 2021. In September 2021, the Columbia participated in the 62nd annual UNITAS exercise off South America. 2019 shooting On 4 December 2019, while the Columbia was in dry dock, a crew member on guard duty shot and killed two civilian employees and injured another before shooting and killing himself. Machinist's Mate Auxiliary Fireman Gabriel Romero, 22, used duty weapons issued to him as a member of the submarine's Topside Roving Patrol. Later investigation by the Navy determined that Romero was "likely unfit" for service on a submarine and that officers and senior enlisted sailors aboard the Columbia had failed to recognize and coordinate action on his deteriorating mental state. Awards In July 2015, the