Hawker Siddeley Harrier the AV-8C configuration; this programme involved the installation of ECM equipment and adding a new inertial navigation system to the aircraft's avionics. Substantial changes were the Lift Improvement Devices, to increase VTOL performance; at the same time several airframe components were restored or replaced to extend the life of the aircraft. Spain's Harriers, designated AV-8S or VA.1 Matador for the single-seater and TAV-8S or VAE.1 for the two-seater, were almost identical to USMC Harriers differing only in the radios fitted. The Royal Navy's Fleet Air Arm (FAA) operated a substantially modified variant of the Harrier, the British Aerospace Sea Harrier.
Joint Combat Aircraft the UK version of the JCA would operate from the two newly ordered "Queen Elizabeth"-class aircraft carriers, the selection of the aircraft was closely linked to the design of the carrier. Candidates for the JCA were thus listed by carrier type: Following the 1998 Strategic Defence Review the Navy's Harrier FA.2s and RAF Harrier GR.7s were merged to form Joint Force 2000 (later Joint Force Harrier). As such the requirement was revised to include the replacement of the RAF Harrier force; this led to the renaming of the project as the Future Joint Combat Aircraft (FJCA) in 2001. Later, in