Tank
With World War II the multi-turreted tanks proved impracticable, and as the single turret on a low hull design became standard, crews became standardized around a crew of four or five. In those tanks with a fifth crew member, usually three were located in the turret (as described above) while the fifth was most often seated in the hull next to the driver, and operated the hull machine gun in addition to acting as a co-driver or radio operator. Well-designed crew stations, giving proper considerations to comfort and ergonomics, are an important factor in the combat effectiveness of a tank, as it limits fatigue and speeds up individual actions.
Horses in World War II
The 1944 Cavalry Corps, in turn, had up to 103 tanks and tank destroyers in addition to three Cavalry Divisions that once again were made lean and light and dependent on horse alone (4,700 men with 76-mm field guns and no armor). By the end of the war with Germany, Soviet cavalry returned to its pre-war nominal strength of seven cavalry corps, or one cavalry corps per each tank army. The CMGs of the period (one Tank Corps and one Cavalry Corps) were regularly weapons of choice in operations where terrain prohibited the use of fully deployed Tank Armies.