However, with the appearance of the new tank, development in other countries, such as the American M60, the West German Leopard, the French AMX30 and the British Chieftain, meant the T54 and its improved version, T55, gradually lost their superiority.
It was under these circumstances that the T62 tank made its first official appearance in the victory parade to celebrate the 20th anniversary of the victory over Germany on May 9th 1965. It was the Soviet Union's reply to the Western new tanks. However, eight years later in October 1973, Israeli troops captured a considerable number of Arab T62 tanks and about ten of these were sent to the U.S. and put through exhaustive tests, which revealed everything about the tank which had been veiled in mystery.
The T62 tank has many similarities to the T54/55, both in external shape and mechanism. It is characterized by adopting a 115mm smoothbored gun as its main armament. Ordinary tank guns are rifled to stabilize the projectile in flight by spinning it. The smooth-bored gun has a projectile fitted with folder fins which, when fired from the muzzle, unfold to stabilize its flight. This gun, US-TS(2A-20), is said to be able to pierce an armour plate as thick as 270mm at 2,000m distance when its APDSFS (Armour Piercing Discarding Sabat-Fin Stabilized), discharged at a muzzle velocity of 1,680m/sec., hits the target at an angle of 90o. However, the accuracy of fire seems to be reduces at ranges over 1500m. Three kinds of projectiles can be used : armour piercing sheels with discarding sabot, anti-tank, and common shells. Forty rounds are carried, and US Army tests showed the rate of fire is four rounds per minute, which is below the level of American and European tanks. The loading angle of the gun is limited as the space inside the turret is made small to minimize the possibility of being hit. The angle of depression of the main gun is -4o, and this, also, is considered a tactical disadvantage. The second armament is a machine gun mounted coaxially with the main gun. The T62A also has a 12.7mm DShk machine gun for anti-aircraft use, and this, together with gunner's cupola type hatch, identifies the tank. It was generally thought that both types of tank used V2-62 water-cooled V 12-cylinder diesel engines with outputs of 700hp. However, the T62 tanks tested by the US Army were equipped with the same V2-55 engine with an output of 580 hp as in the T55. Different engines may be used according to whether the tanks are for domestic use or for export, but details are not known. The T62 has very similar running gear to the T55. The tank is able to lay a smoke screen 250-400m long and has a gamma ray sensor and air cleaner as protection against nuclear weapons.