Second World War No. 11 Squadron was established on 25 September 1939 at
RAAF Station Richmond, New South Wales. It was equipped with two
Supermarine Seagulls and two
Short Empire flying boats. The squadron's first
commanding officer was Flight Lieutenant James Alexander. It suffered its first loss on 8 December when one of its aircraft crashed on take-off in Port Moresby; all six crew members were killed. On 12 January, the squadron launched an attack on the Japanese airbase at
Truk, but it was abandoned due to bad weather. Further raids were undertaken throughout the next couple of months around
Rabaul and patrols were undertaken along the north coast of New Guinea during which the squadron lost one aircraft shot down and several others damaged in attacks or in accidents. The squadron also flew evacuation missions, repatriating military personnel and civilians back to Australia as the Japanese attacks intensified. The squadron moved to
Cairns, Queensland in November 1942, and began to interdict Japanese supply convoys moving between
Lae and
Finschhafen. In early March 1943, aircraft from No. 11 Squadron took part in the surveillance of the Japanese convoy that was destroyed in the
Battle of the Bismarck Sea. which required three aircraft to fly over in the RAAF's longest mission of the war. The squadron spent the final months of the war conducting mine-laying operations, including in
Balikpapan Harbour. After Japan surrendered in August 1945, its focus shifted to humanitarian efforts, air dropping supplies to Allied personnel in prisoner-of-war camps, and repatriating newly liberated POWs back to Australia. These operations occupied the squadron until the end of 1945; it was subsequently withdrawn to Australia and officially disbanded on 15 February 1946. Casualties during the war totalled 102 personnel killed. The squadron ceased operations on 1 May 1950 and was briefly disbanded between then and 1 November 1950, when it re-formed at
RAAF Base Amberley, Queensland, operating modified
Avro Lincoln heavy bombers. Two weeks later, the squadron was transferred to
RAAF Base Pearce, Western Australia, where it conducted patrols over the Indian Ocean. It was re-equipped with
Lockheed P-2 Neptune aircraft during 1951–53, sending crews to the United States to fly the aircraft back, and in May 1954 the squadron re-located to
RAAF Base Richmond. In 1999, the squadron supported the
Australian-led intervention into
East Timor as part of
Operation Warden. Between 2003 and 2013, the squadron's aircraft deployed to the Middle East as part of No. 92 Wing's commitment to Operations
Catalyst,
Falconer and
Slipper. One of the squadron's main roles during these operations was the provision of "over-ground surveillance", providing real-time reconnaissance information to Coalition ground troops in Iraq and Afghanistan, under the direction of ground controllers. In May 2015, it was announced that the squadron would begin transitioning from Orions to
Boeing P-8 Poseidons. The first aircraft was delivered in November 2016 and as of June 2017 the squadron was operating three P-8As. In April 2018, a No. 11 Squadron Poseidon was deployed to Japan to conduct maritime surveillance to prevent sanctions evasions by North Korea as part of
Operation Argos. There have been several subsequent deployments. In October 2019, a Poseidon was deployed to the Middle East in support of a US-led
International Maritime Security Construct, which includes forces from the US, Saudi Arabia, Bahrain and the UK. The squadron took delivery of its twelfth Poseidon in December. In January 2020, during the
Australia-wide bushfires, a No. 11 Squadron Poseidon was utilised under the Emergency Defence Assistance to the Civil Community role as a surveillance asset for Operation Bushfire Assist. On 26 May 2022, during a Defence Force maritime surveillance mission, a Poseidon later identified as A47-008, callsign ASY-189, was intercepted by a
PLAAF J-16 fighter jet in International Airspace over the
South China Sea. The Defence Minister stated that the J-16 deployed
flares and
chaff that was ingested into the P-8A's engine. ==Aircraft operated==