The T-40 amphibious scout tank was an

amphibious Amphibious means able to use either land or water. In particular it may refer to: Animals * Amphibian, a vertebrate animal of the class Amphibia (many of which live on land and breed in water) * Amphibious caterpillar * Amphibious fish, a fish ...

light tank A light tank is a tank variant initially designed for rapid movements in and out of combat, to outmaneuver heavier tanks. It is smaller in size with thinner armor and a less powerful main gun, tailored for better tactical mobility and ease ...

used by the

Soviet Union The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen nationa ...

during

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the World War II by country, vast majority of the world's countries—including all of the great power ...

. It was armed with one 12.7 mm (0.5 in)

DShK The DShK 1938 (Cyrillic: ДШК, for russian: Дегтярёва-Шпагина Крупнокалиберный, Degtyaryova-Shpagina Krupnokaliberny, links=no, "Degtyaryov-Shpagin large-calibre") is a Soviet heavy machine gun with a V-shaped but ...

machine gun. It was one of the few tanks that could cross an unfordable river without a bridge. It was primarily intended to equip reconnaissance units. A land-based version of the T-40, the T-30/"T-40" T-60, was produced, although was later replaced by the "true" T-60. The T-60 was cheaper, simpler, better-armed, and could fulfill most of the same roles, so T-40 production was halted. The vehicle served mainly in

Operation Barbarossa Operation Barbarossa (german: link=no, Unternehmen Barbarossa; ) was the invasion of the Soviet Union by Nazi Germany and many of its Axis allies, starting on Sunday, 22 June 1941, during the Second World War. The operation, code-named afte ...

and the defense of Moscow, and it was rarely seen after that point, although it was used in Soviet training schools until 1946. A total 12 examples of the type were later fitted with Katyusha rocket launchers, firing 82 mm unguided rockets from a 24-rail launcher.

Importance

Amphibious capability was important to the

Red Army The Workers' and Peasants' Red Army (Russian language, Russian: Рабо́че-крестья́нская Кра́сная армия),) often shortened to the Red Army, was the army and air force of the Russian Soviet Federative Socialist R ...

, as evidenced by the production of over 1,500 amphibious tanks in the 1930s. The T-40 was intended to replace the aging T-37 and T-38 amphibious light tanks. It was a superior design, but due to the pressures of war the Soviets favored the production of simpler tank designs, so only a small number of T-40s were built.

Development

The T-40 was an improvement over the T-37 and T-38 in several respects. The coil-spring suspension of the T-38 was replaced by a modern

torsion-bar suspension A torsion bar suspension, also known as a torsion spring suspension, is any vehicle suspension that uses a torsion bar as its main weight-bearing spring. One end of a long metal bar is attached firmly to the vehicle chassis; the opposite end termi ...

with four pairs of road wheels. The boat-shaped hull was entirely welded, in contrast to the

rivet A rivet is a permanent mechanical fastener. Before being installed, a rivet consists of a smooth cylindrical shaft with a head on one end. The end opposite to the head is called the ''tail''. On installation, the rivet is placed in a punched ...

ed hulls of the T-37 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

heavy

machine gun A machine gun is a fully automatic, rifled autoloading firearm designed for sustained direct fire with rifle cartridges. Other automatic firearms such as automatic shotguns and automatic rifles (including assault rifles and battle rifles ...

, which was a much more potent weapon than the 7.62 mm DT machine gun mounted on the T-37 and the T-38.Gudgin, p. 108. 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. Buoyancy was provided by the large boat-shaped hull.Hogg, p. 94.

Production

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

reconnaissance In military operations, reconnaissance or scouting is the exploration of an area by military forces to obtain information about enemy forces, terrain, and other activities. Examples of reconnaissance include patrolling by troops ( skirmishe ...

units. As the need for large numbers of tanks became critical, a secondary non-amphibious variant was designed on the T-40 chassis. Due to delays with design of newer model, T-40 was modified to have thicker armor, 20 mm

TNSh The ShVAK ( ru , ШВАК: Шпитальный-Владимиров Авиационный Крупнокалиберный, Shpitalnyi-Vladimirov Aviatsionnyi Krupnokalibernyi, "Shpitalny-Vladimirov Aviation Large-calibre") was a 20 mm autocanno ...

autocannon, simpler spoken wheels and absent water propulsion system. This design was called T-60, like a different later tank, which led to many confusions, so this tank is often referred as "T-40" T-60 or T-30 (as its blueprint index was 030). The "T-40" T-60 replaced T-40 in September 1941 and was manufactured until summer 1942 along with the "true" T-60. This design was later improved to become the "true" 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 356 T-40s were issued, compared to 594 "T-40" T-60s and over 6,000 "true" T-60s.Bishop, p. 36. A small batch of "T-40" T-60 were produced with BM-8-24 Katyusha rocket racks mounted instead of a turret. This version provided a mobile mount for a 24-rail multiple-launch rocket system, firing 82 mm unguided rockets. A total of 12 T-40 were converted into this model in autumn 1941.Zaloga & Grandsen, p. 30. The T-40 was widely photographed at the time of

and also during the defence of

Moscow Moscow ( , US chiefly ; rus, links=no, Москва, r=Moskva, p=mɐskˈva, a=Москва.ogg) is the capital and largest city of Russia. The city stands on the Moskva River in Central Russia, with a population estimated at 13.0 million ...

. Many were knocked out during the fighting. The type was very rarely seen after the end of 1941, although some T-40s remained in service as late 1946 in some school units.Milsom, p. 114. Romanian forces captured one T-40 as of 1 November 1942.Mark Axworthy, Cornel I. Scafeș, Cristian Crăciunoiu, ''Third Axis, Fourth Ally: Romanian Armed Forces in the European War, 1941-1945'', p. 220

References

Bibliography

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External links

T-40 Development History and Combat Employment
on Battlefield.ru {{Use dmy dates, date=June 2017 Light tanks of the Soviet Union Tracked reconnaissance vehicles World War II tanks of the Soviet Union Amphibious tanks Light tanks of the Cold War World War II light tanks Reconnaissance vehicles of World War II Military vehicles introduced from 1940 to 1944