On 30 April, "Winged Arrow" put to sea with a full complement of Army replacement troops, bound for Oahu where she arrived on 6 May. There, she practiced amphibious operations with soldiers from the Army's 27th Division in preparation for the occupation of the Mariana Islands. At the end of May, she departed Pearl Harbor with troops embarked, bound for Kwajalein in the Marshalls where she arrived on 9 June. Since "Winged Arrow"s embarked troops were assigned to the floating reserve, they were not scheduled to be on hand at Saipan on "D-day". Therefore, she remained at Kwajalein for several days before departing there on a schedule calculated to put her off Saipan on 17 June, two days after the initial assault. The following day, she transferred her troops to LSTs; and they landed at Agingan Point on Saipan. The transport then retired to Eniwetok to prepare for the second phase of the Marianas operation, the landings on Tinian.