Of all the helicopters in the world, the Mil Mi-8 is the best selling, with more than 17,000 units sold. This was something the Soviet military did not envisage, as shown by the fact that they turned down Michael Mil’s proposal to develop his Mi-8 twin turbine transport helicopter in the second half of the 1950s. The only way Mil could proceed was by developing an Mi-4 upgraded with two turbine engines mounted on the roof. This gave him the opportunity to redesign the entire nose section, because of the Mi-4’s nose engine placement. Nevertheless, the first prototype had to use a single 2700 shp Soloviev turbo shaft engine, because the all-new Isotov T2 turbo shaft versions had not yet been produced. Its maiden flight was in 1961. In the meantime, Michael Mil also won the support of Nikita Khrushchev in 1959 (First Secretary of the Communist Party of the Soviet Union at that time) after he took a flight in the American presidential helicopter (a Sikorsky S-58). Khrushchev was impressed, and wanted a Russian equivalent. Mil convinced him that the Mi-8 was best suited to the task, and not the updated Mi-4 model already modified for that purpose. Finally, the Mi-8 was based on an all-new design for its transmission system, cockpit and Isotov turbo shaft engines. The latter were the Soviet Union’s first such engines designed especially for helicopter operations. In 1963, the rotor system with four blades was upgraded to a five-bladed version. The tail section and parts of the fuselage were borrowed from the Mi-4. The machine is operated by a crew of three and can accommodate 28 passengers easily. Clamshell doors are used to load bulky goods conveniently. The cockpit is characterized by its excellent view. During the Vietnam War, the Soviet military learned how the US Army successfully deployed its Bell 204/205 Huey helicopters. This marked the start of a long and very successful career for the Mi-8 in the Soviet Army. Aeroflot also used many Mi-8 machines for civilian purposes, which was this helicopter’s primary design goal. The export versions of the Mi-8 use the designation Mi-17.
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