The combined forces of Australia, the Philippines, and the United States conducted a multilateral maritime cooperative activity (MCA) within the Philippines' exclusive economic zone from August 19 to 25.
The US Navy said the MCA, "continues a demonstrated collective commitment to strengthening regional and international cooperation in support of a free and open Indo-Pacific."
As the 10th MCA of 2026, this exercise expanded capabilities at sea by incorporating and refining shared specialised procedures and maritime doctrines.
The seven-day exercise also focused on tactical interoperability, featuring visit, board, search and seizure; search and rescue; deck landing qualifications; vertical replenishment; replenishment-at-sea; and anti-submarine warfare (ASW). This iteration built upon the ASW serials developed and refined in previous MCAs.
The US Navy said MCAs are conducted in a manner consistent with international law and with due regard to the safety, navigational rights, and freedoms of all nations.
Participating units included the Supply-class replenishment oiler ship HMAS Supply and one MH-60R Seahawk anti-submarine helicopter from the Royal Australian Navy; one P-8A Poseidon maritime patrol and reconnaissance aircraft from the Royal Australian Air Force; two FA-50PH fighter jets and one Cessna C-208B Grand Caravan EX utility aircraft from the Philippine Air Force; the Teresa Magbanua-class multi-role response vessel BRP Teresa Magbanua of the Philippine Coast Guard; the Miguel Malvar-class guided-missile frigate BRP Diego Silang and one AW159 Wildcat helicopter from the Philippine Navy; and the Independence-class littoral combat ship USS Santa Barbara and one P-8A Poseidon from the US Navy.
