The Myasishchev M-4 Molot (Russian: Молот (Hammer), USAF/DoD reporting name "Type 37",[2][3] ASCC reporting name Bison[4]) was a four-engined strategic bomber designed by Vladimir Mikhailovich Myasishchev and manufactured by the Soviet Union in the 1950s to provide a Long Range Aviation bomber capable of attacking targets in North America.

The aircraft fell well short of its intended range and was not fully capable of attacking the most valuable targets in the United States.

In spite of the failure to produce a capable strategic design and the resulting small numbers, the M-4 nevertheless sparked fears of a "bomber gap" when 18 of the aircraft were flown in a public demonstration on May Day in 1954.

The design was updated with more efficient engines, inflight refuelling (IFR) support and the removal of the glass nose for optical bombing and moving the radar to this location.

Even with these modifications the design was not truly effective in the nuclear bomber role, and only 125 aircraft, both M-4s and 3Ms, were produced before the production line was shut down for good in 1963.

Following World War II, the Soviet Union prioritized developing a long-range strategic bomber capable of delivering atomic weapons.

The Tu-4 was only ever a stop-gap solution, as unlike the American strategic bomber force that could operate from bases in allied countries close to the USSR, it lacked the range to reach the continental United States, and experiences in the Korean War demonstrated piston engine bombers were extremely vulnerable to jet fighter interception.

The 3M "Bison-B" was powered by four Dobrynin RD-7 turbojets, which had the same thrust as the RD-3M but were 25% more fuel efficient; a nose inflight refueling probe was also added to further increase range.

The center fuselage was considerably redesigned to reduce weight and improve aerodynamics, and the wings were updated with a wider span and area.

From the late 1950s, the M-4 fleet was converted to the tanker configuration through the fit of a hose-drum unit (HDU) and fuel tanks in the bomb bay and removal of all defensive armament.

The single vertical fin/rudder was replaced with two large rectangular fin/rudders at the tips of the horizontal stabilizers to improve control due to the turbulence caused by the cargo pod.

With the withdrawal of the Myasishchev bombers and tankers the vast majority of the retired airframes were broken up under the terms of the relevant arms limitation treaty.