Avro Shackleton - late '40s

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The Avro Shackleton was a British long-range maritime patrol aircraft (MPA) used by the Royal Air Force (RAF) and the South African Air Force (SAAF). It was developed by Avro from the Avro Lincoln bomber, which itself has been a development of the famous wartime Avro Lancaster bomber.

The Shackleton was developed during the late 1940s as part of Britain's military response to the rapid expansion of the Soviet Navy, in particular its submarine force. Produced as the primary type equipping RAF Coastal Command, the Type 696, as it was initially designated, incorporated major elements of the Lincoln, as well as the Avro Tudor passenger aircraft, and was furnished with extensive electronics suites in order to perform the anti-submarine warfare (ASW) mission along with a much improved crew environment to accommodate the long mission times involved in patrol work. Being known for a short time as the Lincoln ASR.3, it was decided that the Type 696 would be named Shackleton in service, after the polar explorer Sir Ernest Shackleton.

In April 1951, it entered operational service with the RAF. The Shackleton was used primarily in the anti-submarine warfare (ASW) and maritime patrol aircraft (MPA) roles; it was also frequently deployed as an aerial search and rescue (SAR) platform and for performing several other secondary roles such as mail delivery and as a crude troop-transport aircraft. In addition to its service with the RAF, South Africa also elected to procure the Shackleton to equip the SAAF. In South African service, the type was operated in the maritime patrol capacity between 1957 and 1984. During March 1971, in one high-profile incident, a number of SAAF Shackletons was used to effect during the SS Wafra oil spill, having intentionally sunk the stricken oil tanker using depth charges in order to prevent further ecological contamination.

During the 1970s, the Shackleton was replaced in the maritime patrol role by the jet-powered Hawker Siddeley Nimrod. During its later life, a small number of the RAF's existing Shackletons received extensive modifications in order to adapt them to perform the airborne early warning (AEW) role. The type continued to be used in this support capacity until 1991, at which point it has been replaced by the newer Boeing E-3 Sentry AEW aircraft. These were the last examples of the type remaining in active service.

https://en.wikipedia.org/wiki/South_African_Air_Force

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Avro Shackleton - Wikipedia