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.
Hawker Aircraft it merged with the engine and automotive company Armstrong Siddeley and its subsidiary, Armstrong Whitworth Aircraft, to form Hawker Siddeley Aircraft. This group also encompassed A. V. Roe and Company (Avro). Hawker Aircraft continued to produce designs under its own name as part of Hawker Siddeley Aircraft, from 1955 a division of Hawker Siddeley Group. The "Hawker" brand name was dropped, along with those of the sister companies, in 1963; the Hawker P.1127 was the last aircraft to carry the brand. The Hawker legacy was maintained by the American company Raytheon who produced business jets (including some derived from the