Russia continues to deliver ancient T-55 tanks to its forces in Ukraine. Russia stored thousands of these tanks in eastern Russia, where some received a few upgrades before departing for Ukraine. The T-55 was an upgrade, which included protection from nuclear radiation, to the earlier T-54. T-55s entered service in 1959. About 100,000 T-54/55 tanks were produced between 1946 and 1983. Thousands, mainly late model T-55s, are still in use in active (kept ready to use) storage. T-55s weigh 36 tons, have a four man crew and a 100mm gun, with 43 shells on board. There is also a coaxial 7.62mm machine-gun mounted next to the cannon and is used when the 100mm gun is not needed or is out of shells. There is also a 12.7mm machine-gun on top of the turret. This is operated by a crew member standing partially outside the turret to operate machine-gun against aircraft or ground targets. This is often dangerous if anyone is firing at the tank. T-55 armor is vulnerable to most tank guns but still offers protection from heavy machine-guns and somewhat less protection from 20-30mm autocannon shells that are often fired from modern IFV (Infantry fighting vehicles). The IFV is vulnerable to the T-55s 100mm gun.
T-55s are propelled by a 580 HP diesel engine at up to 51 kilometers an hour. Some late model T-55s had an 800 HP engine. Range on internal fuel is 425 kilometers. This can be increased to 610 kilometers if external fuel tanks are mounted on the rear of the tank. T-55s have been in action since the 1950s. From the 1960s the T-55 was no longer a first-line tank but was used in situations that did not require the most modern tank. This often included supporting infantry attacks or crowd control. Technically, the final upgrade of the T-55 was the early model of the T-62 that appeared in the early 1969s while T-55s were still in production and that continued until the 1980s. That did not stop new Russian tanks from being developed and manufactured. The most prominent of these was the T-62 and T-72.
Russia still maintains a tank maintenance and modernization facility in the Russian Far East (near the Pacific Coast and the Chinese and North Korean borders. This facility, the 1295th Central Tank Reserve and Storage Base, dates from the Cold War, when many Russian military logistics operations were placed in remote areas that could be reached by the extensive Russian railroad system. This facility stores and maintains T-55s as well as T-62s and T-72s. These reserves have been drawn in a lot to support operations in Ukraine. When the T-72 autoloader proved extremely vulnerable to Western anti-tank top attack weapons, older models like T-55s and T-62s were issued. These tanks lacked an autoloader and still used four man crews. So, they were called on to provide tank support for Russian troops in Ukraine. There are over a hundred T-62s at this facility and currently these are the ones being sent to Russian troops in Ukraine. The 36-ton T-62 has a crew of four and is armed with a 115mm gun plus a coaxial 7.62mm machine-gun and a 12.7mm machine-gun on top of the turret. The T-62 is powered by a 580 HP diesel engine that provides a top road speed of 50 kilometers an hour and a top off-road speed of 40 kilometers an hour. Road range on internal fuel is 450 kilometers, or 650 kilometers if additional fuel tanks are carried on the rear deck. Over 22,000 T-62s were built between 1961 and the early 1980s. Most were produced in Russia but production continued in North Korea into the early 1980s. North Korea still uses its T-62s. The T-62 is very similar to the T-55 and uses some of the same components. The T-62 is considered an upgrade of the T-55 and it is.
Russia is often criticized for maintaining stockpiles of older armored vehicles. The Russians are being practical because they understand the new models often have unseen flaws that are not apparent until the tank is in combat.