78.2 (TG 78.2), one of two escort carrier task groups providing close air support for the troops ashore, until the middle of the first week in May. After a respite at Manus, Ammen departed Seeadler Harbor in mid-May in company again with Admiral Crutchley's Australian and American cruisers and destroyers. The warships steamed to Hollandia, New Guinea, where they took station offshore to cover the invasion force assembled there. After sundown on 16 May, the entire force began the voyage to the Wakde-Sarmi area of northwestern New Guinea. From 17 to 21 May, Ammen and her consorts brought their guns to bear on Japanese targets in support of the troops charged with the seizure of the region. On 27 May, the destroyer was off Biak in the Schouten Islands located just to the north of the western end of New Guinea and, due east of the peninsula then known as the Vogelkop. During the amphibious assault at Bosnik on the southeastern coast of Biak, Ammens guns struck at enemy positions once more. After the initial landings, Ammens cruiser-destroyer force alternated with Rear Admiral Russell S. Berkey's TF 75 built around , , and in covering the invasion forces from enemy air and naval interference. Ammens group fought off several half-hearted air attacks and foiled an attempted reinforcement by destroyers on the night of 8–9 June. The destroyer and her colleagues concluded their part in the Biak operation at the end of the third week in June and entered Seeadler Harbor for a week of upkeep. On 30 June, the warship put to sea in the screen of the bombardment force assigned to the seizure of Noemfoor, an island located between Biak and the Vogelkop. During the landings on 2 July, Ammen drew no gunfire support missions and so, contented herself with antisubmarine and antiaircraft defense patrols against an enemy notable only for his absence. Between the conclusion of her part in the Noemfoor occupation and the Sansapor operation late in July, the destroyer carried out harassment missions against bypassed Japanese garrisons on the New Guinea coast from the base at Aitape. During the last four days of July, Ammen participated in the unopposed landings at Cape Sansapor on the northwestern coast of the Vogelkop. After Sansapor, the warship embarked upon a voyage to Sydney, Australia, for an 18-day liberty and upkeep call. On 26 August, Ammen headed back to the