[3][4][5] In 1947 with her war and relief work done she was laid up in at Wilmington, North Carolina and later the James River as part of the National Defense Reserve Fleet.

In addition to these voyages, the vessel made eight short cruises to the Caribbean for replenishment of bases and units there as well as for training and liberty.

Between August and November 1960, Alcor underwent two restricted availabilities at the Norfolk Naval Shipyard which altered the cargo ship to enable her to transport, monitor, and handle Polaris missiles and their parts.

In March, Alcor got underway for her first of 15 resupply voyages to Holy Loch, Scotland, during the next four years in support of fleet ballistic missile operations.

In 1962, her home port was changed to Charleston, South Carolina, to facilitate the loading of provisions and Polaris missiles for the tender deployed at Holy Loch.

In April 1964, when the second overseas FBM resupply site was activated in Rota, Spain, she began operations replenishing the newly commissioned tender USS Holland (AS-32) based there and made six round trips during the first year.