The Molot (Hammer) was designed as a strategic bomber, but excessive fuel consumption of its engines and other design shortcomings limited its range to 8,000 km, which was insufficient for striking North American targets and returning to base. Consequently, along with the development of an improved version of the bomber with more fuel-efficient bypass engines and a new wing, a program was also initiated to develop a specialized aircraft for aerial refueling. To facilitate operational support and formation flight in the refueling process the bomber and the tanker aircraft were intended to have identical design and performance characteristics.
Development of an intercontinental bomber with a strike capability at US-territory began in the early 1950s. The governmental order of 24 March 1951 provided for the establishment of a new design bureau headed by V.M. Myasishchev. The design bureau was in charge of organizing and manufacturing the development of the bomber which would have a range of 11000-12000 km, a maximum speed of 900km/h and could carry a payload of 5000 kg. The Bison was a Four-engined, swept-wing jet bomber with engines were buried in the wing roots. An unusual feature was the tandem landing gear, with small stabilising wheels at the tips of the drooping wings, and a nosewheel leg extended at take-off to achieve the correct angle of incidence.
M-4 (built from 1954) – a high-speed strategic heavy bomber powered by four Mikulin-designed AM-3A turbojet engines. Maximum takeoff weight–184,000 kg; maximum speed – 950 km/h; flight range – 9,100 km;bomb load – 24,000 kg. Crew – 8 members. Before 1957, two experimental and 32 production M-4s were made. Starting from 1958, all M-4 bombers were converted into refueler aircraft, which operated for 30 years in the Long-Range Aviation.