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.

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 Battle of the Atlantic was a crucial element of the Second World War, in which Britain sought to protect its shipping from the German U-boat threat.

VW 126 was tested at Boscombe Down in August 1951, particular attention being paid to changes made to improve its ground handling, such as the addition of toebrakes and a lockable rudder system.

In order to keep pace with changing submarine threats, the Mk 2 force was progressively upgraded, with Phase I, II and III modifications introducing improved radar, weapons and other systems, as well as structural work to increase fatigue life.

The Type 719 Shackleton IV, later known as the MR 4, was a projected variant intended to meet a Canadian requirement for a long-range patrol aircraft.

The MR 4 would have been practically a new aircraft, sharing only the nose, cockpit, and outer wings with earlier variants; it would have also been powered by the Napier Nomad compound engine.

[23] The Shackleton IV was cancelled in 1955 and the Canadian requirement subsequently met by the Britannia Maritime Reconnaissance later to emerge as the Canadair Argus.

[28][29] Other equipment included droppable sonobuoys, electronic warfare support measures and an Autolycus diesel fume detection system.

[30] Weapons carried included up to nine bombs, three homing torpedoes or depth-charges; the aircraft also had two 20 mm cannon in a Bristol dorsal turret.

The prototype MR 3 was lost due to poor stalling characteristics; this was rectified prior to production, although a satisfactory stall-warning device was not installed until 1969.

The Shackleton is often incorrectly assigned the unfortunate distinction of holding the record for the highest number of aircrew killed in one type in peacetime in the RAF.

[33] The true figures suggest rather differently in that some of its contemporaries fared far worse, such as the Gloster Meteor with over 430 fatal losses of aircrew[34] against the Shackleton's 156.

The RAF made 1,635 raids, dropping 1,094 tons and firing 900 rockets at the interior of Oman between July and December 1958 targeting insurgents, mountain top villages, water channels and crops in a war that remained under low profile.

[44] During this period, equipment upgrades had become routine in order to keep pace with ever more capable submarines; problems with airframe fatigue were identified, leading to several programmes being carried out to strengthen the aircraft and thus extend its viable service life.

In 1966, nuclear depth charges were introduced to the Shackleton's arsenal with the aim of countering the Soviets' development of deep-diving submarines.

[48] In 1969, a jet-powered replacement patrol aircraft, the Hawker Siddeley Nimrod, began to enter RAF service, which was to spell the end for the Shackleton in most roles.

While radically differing in external appearance, the Shackleton and the initial version of the Nimrod shared many sensor systems and onboard equipment.

[51] In the postwar situation, the South African Air Force sought a large and capable platform to perform the maritime patrol role.

After evaluating four RAF MR 2s in 1953, an order was placed for eight Shackletons as a replacement for the SAAF's aging Short Sunderland maritime patrol aircraft.

The type typically patrolled the sea lanes around the Cape of Good Hope, often monitoring Soviet vessels traversing between the Indian and Atlantic oceans.

The Shackleton was briefly used in low-level overland patrols along the Southern Rhodesian border, but these duties ended following concerns of the disturbance of wildlife.

[51] Due to an embargo imposed by the United Nations over South Africa's policy of apartheid, acquiring components for the Shackleton fleet became increasingly difficult and thus the aircraft's serviceability suffered.

[51] The fleet had been modified to Phase III standards prior to the implementation of the arms embargo, albeit without the auxiliary Viper engine.

[54] Two of the aircraft were re-sparred, 1716 J in the United Kingdom and 1717 O in South Africa by the SAAF, but the lack of engine spares and tyres, together with airframe fatigue, took a gradual toll.

[58] Shackleton AEW.2 In 1971 twelve MR.2s were converted at Woodford and Bitteswell as Airborne Early Warning aircraft, the first AEW.2 flew on 30 September 1971 and the type entered service with 8 Squadron on 1 January 1972.

The tailwheel configuration was replaced by a tricycle undercarriage, addition of a nose entrance hatch, wingtip tanks to increase fuel capacity.

[59] The Phase 2 update introduced electronic countermeasures (ECM) equipment, the distinctive Orange Harvest 'spark plug' and an improved High Frequency radio.

A new navigation system was also fitted and there were some modification to the internal arrangement, including a shorter crew rest area to give more room for the tactical positions.