The Mil Mi-8 (, NATO reporting name: Hip) is a medium twin-turbine helicopter, originally designed by the Soviet Union in the 1960s and introduced into the Soviet Air Force in 1968. It is now produced by Russia. In addition to its most common role as a transport helicopter, the Mi-8 is also used as an airborne command post, armed gunship, and reconnaissance platform. Along with the related, more powerful Mil Mi-17, the Mi-8 is among the world's most-produced helicopters, used by over 50 countries. As of 2015, when combined the two helicopters are the third most common operational military aircraft in the world. Design and development Mikhail Mil originally approached the Soviet government with a proposal to design an all-new two-engined turbine helicopter in 1959 after the success of the Mil Mi-4 and the emergence and effectiveness of turbines used in the Mil Mi-6. After design and development, the Mi-8 was subsequently introduced into the Soviet Air Force in 1967. The Soviet military originally argued against a new helicopter, as they were content with the current Mil Mi-4. To counter this, Mikhail Mil proposed that the new helicopter was more of an update to new turbine engines rather than an entirely new helicopter, which persuaded the council of ministers to proceed with production. Due to the position of the engine, this enabled Mikhail Mil to justify redesigning the entire front half of the aircraft around the single engine. The prototype, which was named V-8, was designed in 1958 and based on the Mil Mi-4 with a larger cabin. Powered by an AI-24 2,010 kW (2,700 shp) Soloviev turboshaft engine, the single engined V-8 prototype had its maiden flight in June 1961 and was first shown on Soviet Aviation Day parade (Tushino Air Parade) in July 1961. During an official visit to the United States in September 1959, Nikita Khrushchev took a flight in the S-58 presidential helicopter for the first time and was reportedly extremely impressed. On Khrushchev's return, he ordered the creation of a similar helicopter, which was to be ready for the return visit by the American president, to save face. A luxury version of the Mi-4 was quickly created and Khrushchev took an inspection flight, during which Mikhail Mil proposed that his helicopter in development was more suitable. However, it would be necessary to have a second engine for reliability. This gave Mikhail Mil the power under