After serving on the light cruiser during the Battle of Midway and Solomon Islands campaigns, he was promoted to Lieutenant (junior grade) on 1 October 1942.

She was laid down 26 July 1943, by Consolidated Steel Corporation, Orange, Texas; launched 5 September 1943; sponsored by Mrs. Mae H. Koiner, the mother of Lt.

After shakedown off Bermuda, Koiner cleared Charleston, South Carolina, 28 February 1944, to join a convoy at Willemstad, Curaçao, N.W.I., and escort tankers to Mediterranean ports.

For the next six months, she remained on convoy-escort duty in the Atlantic, making four round trip cruises from Curaçao to North Africa and Naples, Italy.

Departing Pearl Harbor 4 August, she was en route to Leyte when President Harry S. Truman announced the end of hostilities with Japan.

From 1956 into 1965, Koiner operated on picket stations off the Washington and California coast to provide early warning in the event of enemy air attack.

The experience Koiner had gained during her patrols off the West Coast enabled the radar picket escort ship to contribute greatly to the surveillance tactics necessary to prevent the flow of supplies by sea to the Viet Cong.