Mil Mi-6

The Mil Mi-6, NATO reporting name Hook, is a Soviet heavy transport helicopter built for the Soviet air forces and for Aeroflot. When it first flew in 1957 it was the largest rotary-wing aircraft in the world, designed to move heavy trucks, tracked vehicles, oil installations and other bulky loads, and to support geologists working in Siberia. Two Soloviev D-25B turboshaft engines drive a five-bladed main rotor, and short fixed wings on the fuselage carry about a fifth of the lift in cruising flight. The cabin could be arranged for up to 65 passengers, 70 parachutists or 41 stretchers, and a sling through the floor could carry external loads of up to 9,000 kilograms. More than 800 were built before production ended in 1981.