The Kestrel was only meant to be a development aircraft for the later P.1154, but was what became the Harrier. The RAF was not pleased about this change of events. The Kestrel was developed under Air Staff Requirement 384. The resulting aircraft had a Pegasus 6 engine, with a new design of air intakes, and redesigned wings to improve longitudinal stability. In December 1966, 60 aircraft were ordered by the Government, and by 1967 had been christened as the Harrier.
