As a consequence, it was intended to undertake as little in the way of modification as possible – the AN/APS-20 radar[2] from the Skyraider would be mounted in a radome under the fuselage of an ordinary Gannet AS.1, with the associated electronics and space for two operators inside.

[3] Such were the extensive modifications required that, in December 1954, it was suggested that the AEW version be renamed as the Fairey Albatross, as it was to all intents and purposes a completely different aircraft from its ASW predecessor.

[1] The prototype Gannet AEW.3 first flew in August 1958, with carrier trials taking place using HMS Centaur in November, and the first production aircraft delivered in December.

The AN/APS-20 radar was initially developed during the Second World War and had significant limitations to its capability, in terms of its performance at low level over water (such that it had difficulty differentiating between sea clutter and actual targets), and short-range.

The rotodome was designed to be moveable on its installation, able to tip backwards to allow the radar beam to operate clear of interference from the Gannet's propellers, negating the need to replace the Double Mamba with a turbofan engine assembly.

The Royal Navy developed its airborne early warning tactics in the Skyraider, and then evolved them with the increased capabilities of the Gannet, which had observers trained to interpret the information coming in from the onboard radar.

[7] However, due to the quality of the equipment, the Gannet had limited command and control capability, built as it was around the AN/APS-20 S-Band search radar and AN/APX-7 IFF set,[8] connected to the AN/ART-28 Bellhop datalink.

[10] The Gannet had a three-person crew, consisting of the pilot, located in the cockpit at the front of the aircraft, and a pair of observers in the cabin in the fuselage, accessible via a hatch next to the trailing edge of the wing.

[16] However, in the mid-1960s the British government brought in a series of defence cuts that led to the new carriers and their AEW aircraft being cancelled, and the phased withdrawal of fixed wing aviation in the Royal Navy.

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.

However, this proposal would have had a span of more than 60 ft, which was deemed the upper limit for operation aboard Ark Royal, and thus would have been difficult to accommodate on a ship the size of Invincible.

[23] To coincide with the introduction of the new Queen Elizabeth class, a new AEW system was sought – initially a number of proposals were raised, as it was unclear what type of ship the new carrier would be.

[3] As of 2012, one aircraft (XL500 civil registered as G-KAEW), which was once flown by Charles III, was undergoing comprehensive restoration to airworthy condition by Hunter Flying.