T-40

The T-40 was an amphibious light tank used by the Soviet Union during World War II. It was primarily intended to equip reconnaissance units.

Characteristics
The T-40 was an improvement over the T-37A and T-38 in several respects. The coil-spring suspension of the T-38 was replaced by a modern torsion-bar suspension with four pairs of road wheels.

The boat-shaped hull was entirely welded, in contrast to the riveted hulls of the T-37A and T-38.

The welded, conical turret shape improved protection, although the armor was still very thin.

The vehicle's armament consisted of a single 12.7 mm DShK heavy machine gun, which was a much more potent weapon than the 7.62 mm DT machine gun mounted on the T-37A and the T-38.

Water propulsion was achieved via a small propeller mounted at the rear of the hull. The propeller was set into an indent in the hull rear, and was thus better protected than the exposed propeller of the T-38.

Production
The T-40 entered production just prior to the outbreak of war, and was intended to equip reconnaissance units.

As the need for large numbers of tanks became critical, a secondary non-amphibious variant was designed on the T-40 chassis.

This design was originally designated the T-40S, but was cancelled in favor of the T-60. The T-60 was simpler, cheaper, better armed, and could fulfill most of the same roles.

Under the stress of war, production of the T-40 was halted in favor of the T-60. Thus only 222 T-40s were issued, compared to over 6,000 T-60s.

Variants

 * BM-8-24 - Turret replaced with Katyusha rocket system
 * T-30A - The prototype that became the T-40
 * T-30B - The prototype that was accepted in service as the T-60