Staff Writer (Updated: 10/7/2015):
The Mi-6 originated in a joint Soviet Air Force/Aeroflot need for a large, heavy-lift transport helicopter system. Truth be told, the requirement was a staggering endeavor but matched carefully by the veteran engineers at Mil. The resulting design produced the mammoth V-6 prototype series. First flight of the V-6 occurred in September of 1957 with test pilot N.B. Leshin at the controls. By capability alone, the V-6 would be able to match the muscle of such fixed-wing, transport mounts as the American Lockheed C-130 Hercules, proving that the V-6 certainly had some "kick" to her drive train. Her engine and gearbox components were all large elements making up a most powerful internal lift system. The V-6 ultimately graduated to become a full-production model by 1960 and was showcased in the Soviet inventory under the designation of "Mi-6". She quickly garnered the NATO nickname of "Hook" for recognition purposes. It was common practice for NATO to assign (sometimes derogatory) codenames for Soviet-originated aircraft. Fighters took on codenames beginning with the letter "F" (as in "Fishbed" or "Fulcrum") while bombers were given "B" names (as in "Bison" or "Bear"). Helicopters were, therefore, aptly given "H" names (as in "Hind" or "Hip"). The Mi-6 was notable in the annals of Soviet aircraft lore for she became the first turboshaft-powered helicopter to reach both production status and operational service in their ranks. Furthermore, she became the first helicopter anywhere in the world to break 300km/h, setting a speed record in the process.
Production and Marks
NOTE: Soviet aircraft designations are never as "clean" as some might find in Western inventories where "A", "B" and "C" models are ever-prevalent. Instead, models are designated moreso by their inherent function and marked in the Russian language so designations never truly fall into a convenient chronological listing (at least to the Western observer).
Production of this massive helicopter ultimately yielded over 925 examples with examples originating from Soviet factories from 1960 into 1981.
As mentioned above, the Mi-6 began as the V-6 prototype model (also known under the formal designation of "Zavod No.329 Moscow"). Development culminated in the first production models encompassing the generic "Mi-6" designation with these representing the base heavy-lift transport helicopter family. NATO assigned the codename of "Hook-A" to the first production series. These were followed by the Mi-6A, a dedicated civilian transport model that offered impressive seating for up to 90 passengers. The dedicated military transport derivative became known as the Mi-6T (also "Hook-A" by NATO) and sported seating for up to 70 personnel.
Other militarized variants soon followed and included the Mi-6VKP ("Hook-B") Airborne Electronic Warfare (AEW) platform and aerial command post (identified by its many antenna), the Mi-6BUS ("Hook-C") airborne command post, the Mi-6AYaSh ("Hook-D") airborne command post fitting a SLAR (Side-Looking Airborne Radar) system, the Mi-6PP electronic reconnaissance platform (with AWAC detection and jamming systems), the Mi-6PRTBV fuel transport, the Mi-6R radio communications platform, the Mi-6S MEDEVAC (MEDical EVACuation) variant with room for up to 41 medical litters and the Mi-6TZ/Mi-6ATZ fuel transports, these used to refuel both fixed-wing aircraft and helicopters (though while on the ground and not in-flight).
Of particular note to the Mi-6 variants was the Mi-6M anti-submarine warfare (ASW) platform. This model fitted up to four aerial torpedoes as well as air-to-surface rockets for combating near-surface enemy submarines. The type was further backed by dedicated sub-hunting equipment onboard. Likewise, the militarized Mi-6RVK served as a test-bed for various mobile missile launching systems appearing sometime in 1965.