The Gnat started life as the Folland Fo.140 design for a lightweight fighter, which was preceded by the Fo.139 Midge aerodynamic test aircraft. Both were private ventures by this Hamble based company, which had only limited experience of aircraft building, but foresaw a market for such a concept. Folland's chief designer was W.E.W. Petter, who had previously worked for Westlands and later English Electric. With the latter company he had been responsible for the design of both the Canberra and the prototype Lightning. He had misgivings about the trend towards ever more technically complex and therefore costly interceptor fighters, and saw in the new small turbojets being developed an opportunity to reverse this. The Midge prototype G-39-1 appeared on 11 August 1954, powered by a 1640 lb thrust Armstrong Siddeley Viper 101. This was followed by G-39-2, the prototype Gnat, which had its maiden flight on 18 July 1955 at Boscombe Down, powered by a 3,285 lb thrust Bristol Orpheus B.Or.1 engine. The test reports led to an order for six development machines with Orpheus B.Or.2 engines giving 4,520 lb thrust, the first of these (XK724) having its first flight at Chilbolton 26 May 1956. They weighed less than half the Hunter, for a little over half the cost, but arrived on the scene too late, production of the Hunter being by then in full swing. The Gnat was considered in the ground attack role as a Middle East replacement for the de Havilland Venom, but the Hunter was selected because of it range and its ability to carry heavier warloads. The fighter version of the Gnat was, however, sold to both Finland and India, and the latter country built over 200 under license as well as a development named Ajeet (invincible). Despite the setback of not being selected by the RAF in the fighter role, the aircraft offered potential as a two-seat advanced trainer with supersonic capability and design work had in the meantime been undertaken on this. The proposal met with official approval, and specification T.185D was issued in January 1958, leading to a production order for the 14 pre-production machines. The prototype Gnat T.1 (XM691) first flew at Chilobolton on August 1959, powered by a 4,230 lb Orpheus 100. The Gnat was fully aerobatic with drop tanks in place, and a variety of underwing stores could be carried. Possible armament loads included two 500 lb bombs, two rocket pods, two Sidewinder or Bullpup missiles and two Aden gun pods. Alternatively, reconnaissance camera pods could be fitted. Its flying slab elevators had emergency follow-up elevators, and it was fitted with anti-skid brakes, drag parachute and eleven fuel tanks Specs Power Plant: one 4,230 lb Bristol Siddeley Orpheus Dimensions Span - 24 ft Length - 31 ft 9 in Height - 10 ft 6 in Wing area - 175 sq ft Weights: Empty - 5,900 lbs Loaded (with full external tanks) - 8,400 lb Performance: Max speed - 640 mph at 36,000 ft, initial climb 8,044 ft.min, Range - 1,180 miles Endurance (with drop tanks) - 2 hr 20 min Service ceiling - 48,000 ft