PT-76 amphibious tank

During the years immediately after the Second World War, Soviet projectists developed light all-terrain vehicles as a starting point to incorporate some of the lessons learned with the light tanks produced in small numbers during the previous decade. From the beginning, it was decided that the new light tank had to be fully amphibious. For this, it was included in the specifications a propulsion system based in two water jets to impulse it across the water and the adjustment of the volume of the vehicle to allow it to float without using floating screens. Water jets were placed on each side of the hull with outlets on the rear part and on both sides of the hull above the rearmost road wheels; inlets were undermeath the hull. The rear outlets had lids that could be fully or partially closed, redirecting the water stream to the outlets at the sides of the hull, thus enabling the vehicle to turn or go in reverse. For example, to turn to the left, the left water jet would be covered, while to turn to the right, the right water jet would be covered. To perform a 180 degrees turn, one water jet would aspire water while the other would expel it out. Before entering on the water, it would be raised a shield in the hull front to improve stability and navigability and to prevent water from flooding into the bow of the tank. A tall periscope would allow sight above the shield to the driver. Speed was limited to 10 kilometers/hour in water.


Side and rear view of the standard PT-76, which was the first amphibious tank that operated with water jet propulsion.

Unavoidably, the requirement of the tank being amphibious produced as consequence a tank being quite larger than needed for the strict role of reconnaissance. But this inconvenience would turn to be positive in many of the support vehicles that were made based on the original. denominated. The PT-76 (Plavaushiy Tank or Floating Tank) was seen for the first time in 1952. It had a welded steel hull, armored only to a maximum of 14 millimeters in the sides and 11 millimeters in the glacis, while the turret had similar values overall, which meant that this tank was vulnerable to the fire from any light cannon and even from heavy machine guns. This was so because its amphibious design allowed for less weight than in regular light tanks. The PT-76 carried a crew of three and it was armed with a D-56 76.2-millimeter cannon, having this one an elevation sector between +30 and -4 degrees. As other Soviet tanks, the PT-76 had the inconvenience of a very restricted depression angle for the cannon. Equally as the French light tank AMX-13, this vehicle would have acceptation in small and developing countries, that could not afford to maintain true armored forces equipped with more powerful and expensive tanks. So, the PT-76 was popular in the small countries that were clients of the Soviet Union. It was one of the few tanks that the Americans faced in Vietnam and as expected it resulted very vulnerable against superior tanks and infantry anti-tank weapons. For example, the 3rd March 1969, four American tanks M-48 destroyed two PT-76 of the Viet Cong in an encounter next to Ben-Het.

The PT-76 was produced in large quantities and like it happened with the AMX-13, its chassis was dedicated to many applications, for infantry and support vehicles, including: the armored personnel carrier BTR-50; the infantry combat vehicle BMP; the amphibious transport GSP; the airborne self-propelled anti-tank cannon ASU-85 fitted with an 85-millimeter cannon; the self-propelled air defense system ZSU-23-4 fitted with four 23-millimeter cannons; the transporter/launcher vehicle for the surface-to-surface missiles of the series Frog and the surface-to-air missiles SA-6 Gainful; the SP-74 122 millimeters self-propelled cannon; a bridge-laying vehicle and a wide range of cargo vehicles. Along the years, the modifications made in the tanks PT-76 were limited to the cannon. The improved cannon DT-56TM, fitted with fume extractor and stabilized in two axes, was retroactively installed in all the PT-76 from the Red Army and the armies of other members of the Warsaw Pact. Stabilization in the cannon would make posible to aim and fire while on the water. The PT-76 was used abroad by Afghanistan, Angola, China, Congo, Cuba, Czechoslovakia, East Germany, Egypt, Finland, Hungary, India, Indonesia, Irak, Israel, Laos, North Korea, North Vietnam, Pakistan, Poland, Syria, Uganda and Yugoslavia; it entered combat in Africa, Middle East and Far East. Production was discontinued in the early 1960s in expectance to be replaced by the newer light tank BMD entering service in the end of the decade. China built a modified version with the denomination Type 60. Its hull was similar to the original one but it had a new turret fitted with an 85-millimeter cannon.


Transporter/launcher chassis for a FROG 3 missile, which could reach up to 48 kilometers and be fitted with a nuclear warhead.


This semi-cutaway view shows many details and how the commander had to serve as gunner as well. He uses periscopes to watch around and a telescopic sight to aim the cannon. The driver uses three periscopes of which one is taller to allow vision above the frontal shield, which also provided protection against small caliber bullets and shrapnel.

Categories: Tanks - Cold War - 20th Century - [General] - [General]

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Website: Military History

Article submitted: 2015-01-01