this was followed by the pressurised T5 in 1967. The T51 was an armed export version, sold to Ceylon (present day Sri Lanka), Kuwait and Sudan. It was armed with two 7.7-mm (0.303-inch) machine guns. The T52 was another export version sold to Iraq, South Yemen, Sudan and Venezuela, with the same armament as the T51. The T55 was the final armed export version which was sold to Sudan. A more heavily armed variant of the airframe was developed as the BAC Strikemaster. Design The BAC Jet Provost is a dedicated jet-powered trainer aircraft; according to aviation publication Flight International, it has the distinction of being the first ab initio jet trainer to be standardised by any air force. As designed, it was intended for the Jet Provost to replace, rather than accompany, the use of piston-engine trainer aircraft. The Jet Provost incorporates numerous features to support students during training. The aerodynamic design deliberately avoids speed, instead focusing on favourable handling characteristics and ease of recovery from stall and spin conditions. An emphasis was placed on flexibility, enabling use of the type throughout a range of training operations. The cockpit of the Jet Provost, and much of the operational equipment fittings, is essentially identical to that of the preceding Percival Provost. It features a side-by-side seating arrangement, both positions being fitted with duplicated flight controls and instrumentation, which is well suited to the pupil-instructor pairing. The dual flight controls employs conventional manually-controlled flight control surfaces via a cable-and-tie rod arrangement. A key feature for the era amongst the fittings in the cockpit is the Centralized Warning Panel, which alerts the pilots in the event of a number of unfavourable or hazardous conditions being detected, such as icing conditions, fire, and oxygen failure. The high-flying capabilities of the Jet Provost necessitated the addition of an oxygen system in the cockpit, which was unpressurised on early production aircraft. The Jet Provost has an uncomplicated structure, the airframe being based on the Percival Provost, albeit being strengthened in key areas such as the main wing spar and featuring a substantially different undercarriage arrangement. It possesses an all-metal stressed-skin fuselage built in two sections, the forward section stretching from the rear of the engine bay to the nose comprises a double-frame to absorb the wing and engine loads, while the rear fuselage section uses an orthodox semi-monocoque structure. Major loads across the fuselage are