The first USS Sunnadin (AT-28), a tug, was laid down on 3 December 1918 at the Puget Sound Navy Yard as Katahdin; renamed Sunnadin on 24 February 1919; launched on 28 February 1919; and commissioned on 20 October 1919. It was named for an Anglicized spelling of the Huron Indian town, Sunyendeand.
Sunnadin was assigned to the 14th Naval District and spent almost a quarter of a century in the Hawaiian Islands operating from Pearl Harbor, towing Navy ships and other sea-going craft between ports in the 14th Naval District. During that time, she changed designations twice. On 17 July 1920 when the Navy first adopted alpha-numeric hull designations, she became AT-28.
She was in Pearl Harbor during the Japanese attack there on 7 December 1941. On 15 May 1944, she was redesignated ATO-28. In the fall of 1945, Sunnadin was ordered to report to the Commandant, 12th Naval District, for decommissioning and disposal. Sunnadin was decommissioned on 4 April 1946. Her name was struck from the Navy list on 8 May 1946. On 15 January 1947, she was delivered to the Maritime Commission at Mare Island, California, for disposal.