the phased withdrawal of the gannet aew, as part of the draw-down of fixed wing aviation in the fleet air arm, led to a need for the royal air force to take over the provision of airborne early warning for the uk air defence region. as an interim solution until a purpose built system could be procured, the radar and electronic systems from redundant gannets were fitted to similarly redundant avro shackletons; the shackleton was a maritime patrol aircraft then in the process of being replaced. however, this still meant that the royal navy, then in the process of introducing a new type of small aircraft carrier incapable of operating conventional fixed-wing aircraft, lacked an embedded aew platform that could be used as part of the carrier task group. this lack of organic aew capability following the withdrawal of the gannet was seen as misguided, particularly following the experience of the falklands war, in which the royal navy lost four ships due to the task force being reliant on shipborne air search. as a consequence, the westland sea king helicopter was modified to incorporate the searchwater radar system for use in the aew role from the "invincible" class. the work to convert the first aircraft for this role, from the project being proposed, to a pair of aircraft being deployed as part of the air group aboard on her deployment to the falklands, took 11 weeks.