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
McDonnell Douglas AV-8B Harrier II a demonstration of the Hawker Siddeley Harrier on the Italian Navy ("Marina Militare") helicopter carrier , the country began investigating the possibility of acquiring the Harrier. Early efforts were hindered by a 1937 Italian law that prohibited the navy from operating fixed-wing aircraft because they were the domain of the air force. In early 1989, the law was changed to allow the navy to operate any fixed-wing aircraft with a maximum weight of over 3,300 lb (1,500 kg). Following a lengthy evaluation of the Sea Harrier and AV-8B, an order was placed for two TAV-8Bs in May 1989. Soon, a