Tsar Bomba C), north of the Arctic Circle over the Novaya Zemlya archipelago in the Arctic Ocean. The bomb was dropped from an altitude of ; it was designed to detonate at a height of over the land surface ( above sea level) by barometric sensors. The original, November 1961, United States Atomic Energy Commission estimate of the yield was 55–60 megatons, but since 1992, all Russian sources have stated its yield as 58.6 megatons. First secretary Khrushchev warned in a filmed speech to the Supreme Soviet of the existence of a 100-megaton bomb (technically the design was capable of this yield.)
Over-the-horizon radar experimental model appears to be the Veyer (Hand Fan), which was built in 1949. The next serious Soviet project was Duga, built outside Nikolayev on the Black Sea coast near Odessa. Aimed eastward, Duga first ran on 7 November 1971, and was successfully used to track missile launches from the far east and Pacific Ocean to the testing ground on Novaya Zemlya. This was followed by their first operational system Duga-1, known in the west as Steel Yard, which first broadcast in 1976. Built outside Gomel, near Chernobyl, it was aimed northward and covered the continental United States. Its loud