The original ARI5930/3 Searchwater radar and its display systems of the AEW.2 and AEW.2A were showing their age and technical deficiencies led to operating compromises. Project Cerberus was launched to address these shortcomings and in Mar 2002, the first Sea King ASaC.7 (originally to be the AEW.7) was issued. It carried an improved Searchwater 2000 radar (trialled by XZ570) with accompanying mission systems. At least four of these machines had the Mission System Upgrade applied at the Westland Oldmixon plant.
The Sea King ASaC.7 was retired from UK service (with 849 NAS) at the end of Sep 2018. That left the UK Armed Forces with another capability gap, as the replacement system - the dismountable Crowsnest to be fitted to Merlin airframes in their Squadron workshops - was not then ready for service. The final flight of the ASaC.7 was on 26 Sep 2018 when the last three operational airframes from 849 NAS left RNAS Culdrose via Boscombe Down and Yeovil for VA Fleetlands and storage awaiting disposal.