SS Mission San Fernando was a Type T2-SE-A2 tanker built for the United States Maritime Commission during World War II. After the war she was acquired by the United States Navy as USS Mission San Fernando (AO-122). Later the tanker transferred to the Military Sea Transportation Service as USNS Mission San Fernando (T-AO-122). She was a member of the Mission Buenaventura-class oiler and was named for Mission San Fernando Rey de España in Los Angeles. She was later renamed USNS Muscle Shoals (T-AGM-19) (after Muscle Shoals, Alabama, and, later, USNS Vanguard (T-AG-194).