The RAN returned to East Timor in 2006 under Operation Astute the United Nations-authorised, Australian-led military deployment to East Timor to quell unrest and return stability during the 2006 East Timor crisis. The Royal Australian Navy deployed the Amphibious Ready Group, including the ships; , , "Tobruk" (until approximately 8 June), "Balikpapan", "Tarakan" and "Success" (until 28 May). The RAN also deployed the HMAS "Adelaide" (until 28 May). The Fleet Air Arm contributed one S-70B-2 Seahawk helicopter from 816 Squadron RAN (until 28 May) and two Sea King helicopters from 817 Squadron RAN. The Royal Australian Navy force committed to Operation Astute is apparently the largest amphibious task force in the navy's history.