Hawker Siddeley much larger firms. Out of this decision, came the "order" that all future contracts being offered had to include agreements to merge companies. In 1959, Folland Aircraft was acquired, followed by de Havilland Aircraft Company and Blackburn Aircraft in 1960. In 1963, the names of the constituent companies were dropped, with products being rebranded as ""Hawker Siddeley"" or ""HS"". In this period, the company developed the first operational, and, by far, the most successful VTOL jet aircraft, the Harrier family. This aircraft remained in production into the 1990s and remains in service. In 1948, Hawker Siddeley acquired a factory in
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