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 to the Lightning II would save $1 billion. After entering service in the mid-2010s, the F-35B will start to replace the AV-8B in 2016, with the AV-8B expected to continue service until 2025. Meanwhile, the AV-8B will receive revamped defensive measures, updated data-link capability and targeting sensors, and improved missiles and rockets, among other enhancements. The AV-8B Harrier II is a subsonic attack aircraft of metal and composite construction that retains the basic layout of the Hawker Siddeley Harrier, with horizontal stabilizers and shoulder-mounted wings featuring prominent anhedral (downward slope). The aircraft is powered by a single Rolls-Royce Pegasus turbofan