What began as a maritime patrol version of the Lincoln bomber, the Avro Shackleton became the RAF's principal anti-submarine aircraft during the first half of the Cold War. The Shackleton shared the Lincoln's wing and undercarriage but featured a redesigned and more spacious fuselage as well as Griffon engines with contra-rotating propellers and a pronounced radome under the nose (later replaced by a retractable unit in the rear fuselage). Other subsequent improvements included an Autolycus exhaust trail detector for use against surfaced submarines, and Viper turbojets on the outr engine nacelles to boost takeoff performance. Shackletons began equipping operational units in the early 1950s and also served occassionally as bombers as was the case during the Omani rebellion in 1957. Other roles for this aircraft included search and rescue (SAR) and airborne early warning. The only foreign operator was South Africa and was replaced in RAF service by the Nimrod and E-3 AWACS.

The Avro Type 696 was first flown as a prototype on 9 March 1949 and entered service as the Shackleton GR.1 where they were later redesignated MR.1. These were followed by the MR.1A with minor engine changes and later, the MR.2 with a relocated radome. The MR.3 was the definitive patrol version which adopted various fuselage changes including a tricycle undercarriage and underwing hardpoints (later units included extra turbojet engines). Some of these improvements were eventually fitted to MR.2s as well. Finally, other versions included the T.4 and MR.2(T) trainers (based on the MR.1 and MR.2 respectively) and the AEW.2 early warning system with an APS-20 radar in a large radome under the forward fuselage. These served until 1991 due to the failure of a similar development of the Nimrod.