In
1958, Short was approached by F.G. Miles Ltd (successor company to
Miles Aircraft) which was seeking backing to produce a development of the
Hurel-Dubois Miles HDM.106 Caravan design with a
high aspect ratio wing similar to that of the
Hurel-Dubois HD.31. Short acquired the design and data gathered from trials of the
Miles Aerovan based HDM.105 prototype. After evaluating the Miles proposal, Short rejected the Caravan. They developed their own design for a utility all-metal aircraft which was called the
Short SC.7 Skyvan. The Skyvan is a twin-engined all-metal, high-wing monoplane, with a braced, high aspect ratio wing, and an
unpressurised, square-section
fuselage with twin
fins and rudders. It was popular with freight operators compared to other small aircraft because of its large rear door for loading and unloading freight. Its fuselage resembles the shape of a railroad
boxcar for simplicity and efficiency. Construction started at
Sydenham Airport in 1960, and the first prototype first flew on 17 January 1963, powered by two
Continental piston engines. Later in 1963, the prototype was re-engined with the intended
Turbomeca Astazou II turboprop engines of ; the second prototype (the first Series 2 Skyvan) was initially fitted with
Turbomeca Astazou X turboprop engines of but subsequently the initial production version was powered by
Turbomeca Astazou XII turboprop engines of . In 1967, it was found that the Astazou XII was temperature limited at high altitudes. Consequently, in 1968, production switched to the Skyvan Series 3 aircraft, which replaced the Astazou engines with
Garrett AiResearch TPE331 turboprops of . A total of 149 Skyvans (including the two prototypes) were produced before production ended in 1986. ==Operational history==