Marvin Lyle Thomas was one of the two last ships converted and was operational too late to participate in the postwar port rehabilitation to a significant degree.

[3] Like her sister repair ship, Joe C. Specker (ex Vela (AK-89)), she remained operational with the Army until transferred to Navy's Military Sea Transportation Service (MSTS) in 1952.

Transferred from the Army to the Navy under assignment to the Military Sea Transportation Service on 26 April 1952, Sagitta operated as a summer DEW line resupply ship out of New York City from 1952 through 1959.

During the winters, she carried cargo to Bermuda; San Juan, Puerto Rico; and Cristobal, Panama Canal Zone, annually from 1953 through 1955; and to Guantánamo Bay, Cuba, in 1956.

Transferred to the Maritime Administration on 23 February 1960, she remained in the National Defense Reserve Fleet until 25 April 1966 when she was transferred to the Army for duty as a training vessel, first at Fort Eustis, Virginia, then in about 1972 at Bayboro Harbor, St. Petersburg, Florida as USAV Resource[Note 2] and then at Curtis Bay, Maryland, where she provided stevedore training.