Carro Armato M11/39

Inspired by the British Vickers 6-ton tank design of the late 1920s, the Italians considered the 11-ton Fiat-Ansaldo Carro Armato Medio (“medium tank”) 11/39 a type of “breakthrough tank' (Carro di Rottura). In concept it was at once an improvement upon earlier Italian tankettes and a bit of a regression in overall tank design. It had many weaknesses which shortened its service life, but the type did serve in the North African, East African, and Greek campaigns. A significant deficiency was that its 37 mm Vickers-Terni L/40 main gun was in a hull sponson, with the idea that crews would use this gun against other tanks and defend with the turret armament, a pair of 8 mm machine guns. Additional weaknesses included poor endurance; slowness (top speed of just 20 mph); unreliability; and relatively weak armor (particularly on the sides, top, and rear). Its 30 mm frontal riveted steel armor and turret armor, designed to withstand 20 mm fire, was vulnerable to British 2-pounder (40 mm) guns at any range at which the M11/39’s main gun was effective. It carried a crew of three. The entire run of 96 production tanks occurred in 1939. Within short order, Italian designers modified the M11/39 hull to fit a fully-rotating turret with a 47 mm main gun to develop its successor, the Fiat M13/40, which became Italy's primary tank of WWII.