Obyekt 279 Obyekt 279 was a Soviet prototype heavy tank developed in the Kirov industrial plant , Leningrad by a group headed by the engineer L . Troyanov at the end of 1959 ( " " В конце 1959 года был построен опытный образец " " ) . The work on the tank started in 1957 , which was based on a heavy tank operational requirements developed in 1956 . The special - purpose tank was intended to fight on cross - country terrain that was inaccessible to conventional tanks and act as a vehicle to break through enemy defensive positions . It was planned as a tank of the Supreme Command Reserve . This tank was a unique version boasting increased cross - country capability . The tank featured four - track running gear mounted on two longitudinal , rectangular hollow beams , which were also used as fuel tanks . The tank hull ( with 269 mm armor ) was covered by a thin , elliptical shield protecting it against HEAT shaped - charge ammunition and preventing it from overturning due to the shock wave of a nuclear explosion . It comprised large cast irregular shape structures of variable thickness and slope . The all - cast front part of the hull was rounded in shape with thin armor panels against HEAT projectiles , which ran around the edges of the front and sides of the hull . The sides of the hull were also cast and had similar protective armor panels . The all - cast turret ( front armor thickness 305 mm ) was rounded , with anti - HEAT protective panels mounted at a seventy degree angle . The turret ring was also heavily protected . The tank was fitted with a 130 mm rifled M - 65 ( firing APDS rounds with a muzzle velocity of 1000 m / s ) , and a co - axial 14 . 5 mm KPVT heavy machine gun , stabilized in two planes by a " Groza " stabilizer . The gun was provided with a semi - automatic loading system . Firing control system comprised optical / radar rangefinder , auto - guidance system and L2 night - sight with IR searchlight . The tank suspension was hydro - pneumatic with complex hydrotransformer and three - speed planetary gearbox . The track adjuster was worm - type . The tank was also fitted with NBC protection and auto fire - fighting systems , smoke laying equipment and combat compartment heating / cooling system . The specific ground pressure of this heavy vehicle did not exceed 0 . 6 kgf / cm2 . The track chain , running practically along the whole track length provided for increased cross - country capabilities on swampy terrain , soft soils and area full of cut trees , Czech hedgehog s , antitank obstacles and the like . The powerful 16 - cylinder 1000 - hp engine 2DG - 8M enabled the 60 - ton vehicle to attain 55 km / h speed with active range of 300 km on one refuel . Eventually , one of the reasons this tank project to be abandoned , as other heavy tank projects , was the fact that the Russians stopped operating with heavy fighting vehicles of that type ( tanks and similar ) as of 1960 . Since then , the heaviest ones are kept at about 50 metric tons of weight , that is without counting in any additional equipment such as additional reactive armor , mine clearing devices ( mine ploughs , mine rollers ) etc . It was something concerning the current Soviet policy . On July 22 , 1960 at the demonstration of new technology on the range of Kapustin Yar , Khrushchev strictly forbade any tanks with a weight of more than 37 metric tons to be adopted by the military , having thus written off the entire program of heavy tanks which proven to be so successful ) . Nikita Khrushchev himself was a supporter of guided - missile tanks ( which apparently added to the decision ) , such as the IT - 1 ( ИТ - 1 ) which was armed with Dragon ( Дракон ) ATGMs . Furthermore , the Russians wanted tanks with a suitable weight for crossing their own bridges ( in case of homeland defence situations , similar to the WWII ones ) , which at that time seemed to be unreliable for heavy vehicle crossings . Other reason was the fact that a number of serious deficiencies of the running gear appeared during the trials , such as low nimbleness , the efficiency loss during swampy area crossings , complex and expensive production , maintenance and repair , and impossibility of reduction in the overall height of the tank . The only sample of this unique tank is today exhibited at the Kubinka Tank Museum , 50 km from Moscow .