M50 Super Sherman

The Sherman M-50 and the Sherman M-51, both known abroad as the Super Sherman, were modified versions of the American M4 Sherman tank that served with the Israel Defense Forces from the mid-1950s to early 1980s. The M-51 was also referred to as the Isherman (i.e. Israeli Sherman). However, the designations "Super Sherman" and "Isherman" were never used by the Israeli Defense Forces.

In 1953, an Israeli delegation visited France to examine the new AMX 13 light tank. The tank was armed with the high-velocity 75 mm gun CN 75-50. While the gun was satisfactory, the armor of the French tank was considered too light. Eventually, Israel did purchase the AMX 13, however in a parallel development it was decided to graft the powerful French gun onto the available, familiar and better-armored hull of the American M4 Sherman, the standard tank of the IDF armored units in the early 1950s.

The project started in 1954, and in 1955 a prototype turret was sent from France to Israel. In March 1956 Israeli Ordnance Corps facilities started to convert tanks, using guns received from France. The gun was known in Israel as the M-50 and as a result the upgunned Sherman was designated Sherman M-50. The M-50 was similar to the Sherman Firefly in that it had the original turret of the smaller type (as used by the 75 mm gun M3 armed Shermans), which was fitted with a large counterweight at the rear end.

The first 50 units were based on M4A4 hulls, had a Continental R-975 gasoline engine and VVSS suspension. However, the increased weight of the vehicle combined with narrow tracks led to poor off-road mobility. It was also putting too much strain on the engine, resulting in frequent mechanical failures. Consequently, for the rest of the conversions, hulls fitted with HVSS suspension and Cummins V-8 460 horsepower (340 kW) diesel engine were adopted. These subvariants were sometimes referred to as the M-50 Continental and M-50 Cummins. Diesel engines were also preferred since diesel fuel is less flammable than gasoline, which factors into battlefield survivability. In total, about 300 M-50s were built by 1964 (though it's possible that this number includes 120 155 mm self-propelled guns on Sherman chassis, also designated M-50).

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