In the early 1950’s, the U.S.A. found itself committed to defending the newly formed cold war NATO alliance in Europe against the Warsaw Pact forces, and fighting a hot war in Korea, resulting in a severe shortage of tanks. At the time, the best US tank in service was the M46 Patton, but because of a lack of stocks of M26 Pershings available for the conversion, it was decided to produce an interim design utilizing new concepts from the experimental T42 medium tank, which had been experiencing developmental problems.
Based on a modified hull of the proven M46, the 48.6 ton M47 featured the cast T42 turret with its improved ballistic protection. The turret ring diameter on the hull was increased to fit the T42 turret, housing the M36 90mm main gun with M12 optical stereoscopic rangefinder protruding from the upper corners. A secondary Browning M1919 .30 caliber machine gun was mounted coaxially to the main gun, and another in the bow position of the hull (the last time this was featured in a U.S. tank design), with a Browning M2 .50 caliber machine gun mounted in a pintle on the turret roof. 71 rounds of 90mm ammunition were stored inside the vehicle, with 11 mounted in the ready rack in the turret bustle, 12 on the sides of the hull, and 48 stowed in racks beneath the turret floor. The upper glacis was improved by increasing the slope of the 4-inch (102mm) armor to 60 degrees, and the rotoclone blower was removed from the upper front hull, replaced by a new blower above the turret bustle. The configuration of the hull was further modified from the original by removing the 2nd & 4th track return rollers on each side. Powered in the rear by an improved 800HP Continental AV-1790-5B V-12 air-cooled gasoline engine and Allison/General Motors CD-850-4 transmission, the M47 had a maximum speed of 37 mph (60 km/h) and an operational range of up to 100 miles (160 km). The M47 was the last US tank to require a 5-man crew, which consisted of the driver & co-driver/bow machine gunner stationed in the front of the hull, and the tank commander, gunner, and loader in the turret.
Production for the Ordnance Department began in June 1951 at the Detroit Arsenal, later being taken over by Chrysler, and concluded in November 1953, with some 5481 units produced, with an additional 3095 examples being produced by the American Locomotive Company. By the late 1950’s, the M47 was already declared obsolete in favor of the new M48, and was retired from US service without firing a shot in combat. Beginning in the 1950’s, the M47 was exported through the Military Aid Program to Austria, Belgium, Ethiopia, France, Greece, Italy, Jordan, the Republic of Korea, the Netherlands, Pakistan, Portugal, Iran, Iraq (from Iran), Saudi Arabia, Somalia (from Saudi Arabia), Spain, Sudan (from Saudi Arabia), Turkey, West Germany, and Yugoslavia (later Bosnia & Herzegovina). The M47 has seen combat in the service of Croatia, Iran, Jordan, Pakistan and Somalia.