British Aerospace Harrier II British Aerospace Harrier II The British Aerospace Harrier II is a second-generation vertical/short takeoff and landing (V/STOL) jet aircraft used previously by the Royal Air Force (RAF) and, between 2006 and 2010, the Royal Navy (RN). The aircraft was the latest development of the Harrier Jump Jet family, and was derived from the McDonnell Douglas AV-8B Harrier II. Initial deliveries of the Harrier II were designated in service as Harrier GR5; subsequently upgraded airframes were redesignated accordingly as GR7 and GR9. Under the Joint Force Harrier organisation, both the RAF and RN operated the Harrier II under the RAF's Air
Hawker Siddeley Harrier testing. The two remaining British-based Kestrels were assigned to further trials and experimentation at RAE Bedford with one being modified to use the uprated Pegasus 6 engine. At the time of the development of the P.1127 Hawker and Bristol had also undertaken considerable development work on a supersonic version, the Hawker Siddeley P.1154, to meet a North Atlantic Treaty Organisation (NATO) requirement issued for such an aircraft. The design used a single Bristol Siddeley BS100 engine with four swivelling nozzles, in a fashion similar to the P.1127, and required the use of plenum chamber burning (PCB) to achieve supersonic speeds.