The P.56 Provost, designed at Luton under the direction of Leslie G. Frise for the original Percival Aircraft Company, was the answer to the RAF's first post war specification, T.16/48, for a basic trainer. It was chosen for production in early 1951 and a total of 387 were eventually built.
The possibility of building a jet-powered version of the Provost began to interest the Percival factory and a model of such an aircraft was shown at the 1952 SBAC Display. With a self imposed target of retaining 70 percent of the Provost's structure, the Percival designers found that modifications of the fuselage to accept a small turbojet engine would be relatively simple. A turbojet engine of about 1 500 lbs. thrust was found at Armstrong Siddeley Motor's Coventry works in April 1951. This engine, the ASV.5, originally designed for an expendable target drone, was adopted for use in the Jet Provost and designated as a Viper 101.
Design work on the P.84 Jet Provost started as a private venture but was endorsed by the RAF when the Ministry of Supply (then responsible for military aircraft procurement in Britain) placed a contract for 10 pre-production aircraft. In the first of these, the chief test pilot of what had then become Hunting Percival Aircraft Ltd, R G Wheldon, made the first flight on the 26th June 1954.
Full-scale evaluation led to the RAF ordered the definitive T Mk 3. Production for the RAF was completed by mid 1964, but export markets were found for versions of the T Mk 3 and T Mk 4. These armed variants were all designed and built at Luton, where Hunting Aircraft had succeeded Hunting Percival and had in turn been absorbed into the British Aircraft Corporation.
Further development of the airframe was undertaken to introduce a pressure cockpit and an uprated engine, as well as tip tanks for extra fuel. These entered service as the T Mk 5. A BAC 166 was produced as a test bed for the Viper 20 and a new wing.
Finally came the Strikemaster as the BAC 167 with all the capabilities already described.
The Jet Provost T5 was the final development of the first basic trainer in the world to go into service. As military flying development in the 1960s, the increased emphasis given to work at high altitude placed a severe physiological strain on aircrew unless a pressurised cockpit was provided. In 1964 the original designers of the Jet Provost responded to the need for a pressurised version and began private work on the design. The Jet Provost T5 differed externally from earlier versions by a re-designed hood and a more bulbous shape to accommodate the pressurised cockpit. The prototype T5 made its first flight on 28 February 1967. A total of 110 Jet Provost T5s were produced for the Royal Air Force and the first was handed over to the Central Flying School on 3 September 1969. Between 1973 and 1976, ninety-three were modified by an upgrade in avionics equipment and became T5As. The rough grey coating on the wing of the aircraft was applied in order to break up the smooth airflow and give an early indication of the onset of a stall. The T5’s original clean wing design gave the pilot little prior warning of this potentially dangerous event.