The beam that is attached to a helicopter weighs 60-75 tons.

The helicopter itself weighs 40 tons.

In the early 1970s, new discoveries of oil, gas and various minerals led to a shift in the interests of the Soviet Union from the Southern and Central parts of the state to Siberia, the Far East and the North. Distances between sources of raw materials and transport communications, processing plants, difficult terrain, severe climate significantly complicated the delivery of necessary equipment or extracted raw materials. An invaluable role in the delivery of people and the necessary cargo began to play rotary-winged machines. However, the existing payload of Mi-6/10 helicopters did not satisfy the growing needs of developers and subsoil researchers. The weight of some parts of the necessary equipment has already exceeded the unattainable figure for helicopters - 40 tons. For transportation of such equipment used automobile and railway equipment, since there were no airfields for landing aircraft in these areas. In addition, in the rotorcraft with a large payload, the army units of the Soviet Army were in desperate need to transport new types of weapons to the place of deployment or to specified areas.
By the mid-1970s, the government was tasked with investigating the possibility of interaction of helicopters in one bundle for the movement of large loads and the creation of 2/3 helical heavy-duty helicopters. Under this assignment, the Moscow plant for the construction of helicopters named after M.Mil starts analytical and design studies on the task received. In 1976, the first explorations began at the Milya plant. The possibilities of moving large cargoes by 2/3 Mi-26 transporters on a single suspension were considered, which would require incredible coordinated actions of the pilots and the creation of two or three heavy-duty screw trucks based on the Mi-26. The result of research and analytical activities was the decision of the State Committee for Science and Technology of the Soviet Union, on the preparation of proposals for the creation of rotorcraft with a large payload. This task was proposed to all helicopter design bureaus and plants in the framework of the program of basic directions for the development of aircraft engineering until 1993.