Hawker Siddeley P.1127 Hawker Siddeley P.1127 The Hawker P.1127 and the Hawker Siddeley Kestrel FGA.1 are the experimental and development aircraft that led to the Hawker Siddeley Harrier, the first "vertical and/or short take-off and landing" (V/STOL) jet fighter-bomber. P.1127 development began in 1957, taking advantage of the Bristol Engine Company's choice to invest in the creation of the Pegasus vectored-thrust engine. Testing began in July 1960 and by the end of the year the aircraft had achieved both vertical take-off and horizontal flight. The test program also explored the possibility of use upon aircraft carriers, landing on in 1963. The first three
BAC Jet Provost the addition of a dorsal fillet; the new model was designated as the "Jet Provost T2". On 1 September 1955, the first Jet Provost T2 made its first flight. This variant was used only for development work; in addition to seeing use at Hullavington, three Jet Provost T2s were dispatched overseas for winterization trials in Scandinavia and a series of sales tours across Europe, Canada, the United States of America, and Latin America. In June 1957, a production order was placed for the first 40 of the developed "Jet Provost T3", featuring a more powerful Armstrong Siddeley Viper jet engine,