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
British Aerospace Sea Harrier in 1973, and are now popularly recognised as aircraft carriers. Almost immediately upon their construction, a ski-jump was added to the end of the 170-metre deck, enabling the carriers to effectively operate a small number of V/STOL jets. The Royal Air Force's Hawker Siddeley Harrier GR1s had entered service in April 1969. A navalised variant of the Harrier was developed by Hawker Siddeley to serve on the upcoming ships; this became the Sea Harrier. In 1975, the Royal Navy ordered 24 Sea Harrier "FRS.1" (standing for 'Fighter, Reconnaissance, Strike') aircraft, the first of which entered service in 1978. During this