And, the Soviets themselves had no bomber, even in planning, that could carry the 27-Mg bomb long-range and then pass its 2-m width.
Tsar Bomba was designed and constructed in only 14 weeks after Soviet premier Nikita Sergeevich Khrushchev initiated the project on July 10, 1961. The bomb itself weighed 27 metric tons and was 8 metres long by 2 metres wide; a special parachute had to be designed to allow it to be dropped from an airplane. The fabrication of this parachute required so much material that the Soviet hosiery industry was noticeably disrupted. Tsar Bomba was detonated on October 30, 1961, at a height of 4000 metres over Novaya Zemlya Island in the Arctic Sea; it was dropped from a Tu-95 bomber at 10,500 metres altitude by pilot A. E. Durnovtsev. The fireball touched the ground and reached nearly as high as the release plane and light from the detonation was visible 1000 km away; the mushroom cloud rose as high as 64 km.
The Tsar Bomba had its yield scaled down by replacing the uranium fusion tamper (which amplifies the reaction) with one made of lead to eliminate fast fission by the fusion neutrons. If detonated at full yield, the force of this bomb would have been approximately 6,500 times the 15-16 kiloton bomb detonated at Hiroshima and would have increased the world's total fission fallout since the invention of the atomic bomb by 25%.