Introduced in 1949, the T-54/55 is in service with more countries world-wide and in greater numbers than any other tank manufactured since World War II. The first new tank of the post-World War II Soviet Union, the T-54/55 can trace its lineage back to the IS series Stalin heavy tanks and the revolutionary T-34 medium tanks.
The T-54 entered production in the Soviet Union in 1947, and was fielded with Soviet ground forces in 1949. By 1958, the T-54 had undergone a number of improvements and modifications and was re-designated the T-55. The T-55 represents an evolution of the T-54 rather than a completely new design.
The T-55 was produced by the Soviet Union through 1981. In addition, the T-55 was also produced in China (where it was designated the Type 59), Czechoslovakia, and Poland. The T-55 is capable of fording to a depth of 1.4m without modification and to 5.5m with the addition of a snorkel kit. The T-55 is capable of producing onboard smoke by injecting vaporized diesel fuel directly onto the engine exhaust.
Though time and technology have rendered the T-55 obsolete as a front-line main battle tank, large numbers of 54/55s remain in service with militaries world-wide. The T-55 saw service in Hungary in 1956, Czechoslovakia in 1968, and in Syria in 1970. In addition, it was the main battle tank used by the Arab forces during the 1967 and 1973 Arab-Israeli wars. During the 1970s the T-54/55 also saw extensive use during the border wars in Africa. Since so many T-54/55s remain in service, many countries, such as Israel, Pakistan, and India offer upgrade packages to rebuild existing tanks using more modern, and in many cases Western, fire control components, thus extending their usable life even further.
There are currently seven production models of the T-54/55, and more than a dozen variants.
The T-54/55 tank follows a conventional layout, with a dome-shaped turret centrally located on the hull and the engine mounted in the rear. The 54/55 has a crew of four; driver (located in the left hand side of the hull, forward of the turret) loader (right hand side of the turret) tank commander and gunner (both located on the left side of the turret.
The T-54/55 can be identified by the distinct gap between the first and second of its five large cast road wheels. The 54/55 uses steel track (this may be substituted for padded track in modified versions), a torsion bar "live track" suspension with no return rollers and a rear mounted drive sprocket. The T-55 does not use armored fuel cells. Instead, the fuel is stored in exposed tanks on the track fenders. The engine exhaust is expelled out the left rear side of the hull.
The 100mm cannon is centrally mounted in the turret. The cannon trunions are not protected by an armored mantlet, but rather a canvas sleeve that protects the mechanism from the elements. There is no fume extractor on the T-54, while the T-55 has a bore evacuator mounted on the muzzle of the gun.
There are two hatches on the top of the turret (loader's and tank commanders.) Both hatches open forward. In the T-54 the 12.7mm DShK AA MG is mounted in the commander's station; on the T-55 (""A"" version and beyond) the machine gun is located in the loader's position.
Two infantry support rails (one straight, one curved) are affixed to the turret sides. These may be removed to accommodate ERA, APS or applique armor packages. If present the main IR searchlight will be mounted on top of the turret (to the left of the gun.) An additional searchlight may be mounted on the commander's hatch. If present, the laser rangefinder will be mounted externally on the top of the main gun itself.
Because the T-55 does not use synchronized optics for the main gun, another identifying characteristic of the T-55 is the large sighting oval on the left hand side of the turret next to the gun mantlet. The aperture on the right hand side of the turret is the firing port for the coaxial PKT-T machine gun.