They also were the first U.S. Navy ships specifically designed and launched with an intention that they be operated in a non-commissioned status by the Military Sea Transportation Service, later the Military Sealift Command, with civilian crews working under contract.

The "T" appended to the beginning of their hull numbers indicated civilian manning, a convention still in use today.

At some time after the loss of USNS Potomac (T-AO-150) in 1961, the three survivors were reclassified as transport oilers, and were redesignated as such by having an additional "T" appended to their hull code.

Maumee transported petroleum primarily in the Pacific, operating in this role between mid-December 1956 and probably the mid-1980s.

Potomac transported petroleum from 1957 until 1961, when she was destroyed pierside by a fire and explosions.