M2 Medium Tank - Service

Service

The M2 was already obsolete when it entered service. It compared poorly with the latest European tanks, such as the French S-35, German Panzer III and Soviet BT-7, which were better protected against 37 mm hits. The 37 mm main armament of the M2 was equivalent to the 37 mm in the Panzer III, but the BT-7 (45 mm) and the S-35 (47 mm) had more powerful guns. By 1941, Germany had upgunned the Panzer III with a 50 mm L/42 gun, and the Soviets had fielded the vastly superior T-34, with a 76 mm gun and a sloped 52 mm glacis plate. Given this, the M2 was essentially a stopgap measure until more capable tanks like the M3 Lee and M4 Sherman came along in 1942-43. Although 18 M2s and 94 M2A1s were produced, the Ordnance office recommended in 1942 that they should only be used for training purposes, and they were never sent overseas to combat areas. The U.S. Army fielded M2 and M2A1 with the 67th Infantry Regiment (Medium Tanks) and, subsequently, the 1st Armored Division's 69th Armored Regiment.

For combat it was a poor design, with thin armor, inadequate main armament and a high profile. The four sponson-mounted machine guns proved to be completely unnecessary. But it provided important lessons that were used for the later M3 and M4 medium tanks. In particular, the M2's sloped frontal hull armor (glacis plate) was extremely advanced for a 1939 design, and would become a permanent feature of U.S. tank design. The next medium tank would have to match the German Panzer IV's 75 mm turret gun. Since no suitable turret had been designed in the US, the Lee was designed first to mount a 75 mm gun in the right sponson, which had been tested on an M2; the experimental vehicle was designated T5E2. The Lee's gun was mounted in a conventional turret on a modified M3, to produce the first Sherman eight months after the first Lee.