Hawker P.1121 Staff having been unable to understand the concept of the multi-purpose functionality of the aircraft, which would become commonplace on later aircraft. While seeking a new project to take the place of the P.1121, Camm soon began work upon another new and radical aircraft design, designated as the Hawker Siddeley P.1127. The P.1127 would become the Hawker Siddeley Harrier, the first effective vertical take-off and landing (VTOL) combat aircraft. The Hawker P.1121 was envisioned as being one of the first British-built supersonic fighter aircraft, being projected to be capable of speeds of up to Mach 2.5. It was to have
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