"Implacable" arrived at the BPF's main operating base at Manus Island, in the Admiralty Islands, on 29 May. A week later Rear Admiral Sir Patrick Brind hoisted his flag in preparation for Operation Inmate, an attack on the Japanese naval base at Truk in the Caroline Islands that began on 14 June. Having flown 113 offensive sorties over the two days of the attack, with only one loss of a Seafire to enemy action, the carrier and her escorts returned to Manus Island on 17 June. On 30 June No. 8 Carrier Air Group was formed, absorbing No. 24 Naval Fighter Wing, to control all of the air units aboard "Implacable".