YP-251 was a converted fishing vessel which served in the U.S. Navy during World War II from 1941 to 1945. She operated in the waters of the Territory of Alaska during the war. Before the war, she operated as the commercial fishing vessel MV Foremost from 1924 to 1941. After the war, she again operated as the commercial vessel MV Foremost from 1946 to 1954, then was renamed MV LeRoy.