At 9:30 a.m., specially modified Tupolev Tu-95V "Bear A" bomber, No. 5800302, under the command of Major Andrey Ergorovich Durnovtsev of the 409th Heavy Bomber Air Regiment, departed Olenegorsk Air Base, 92 kilometers (57 miles) south of Murmansk, at 9:30 a.m. The bomber carried a nine-man crew, including navigator Major Ivan Nikoforovich Mite.
The Tu-95 was accompanied by a Tupolev Tu-16 instrumentation ship (No. 3709), under the command of Colonel Vladimir Fedorovich Martynenko. Some sources say that the two bombers were escorted by a flight of fully-armed fighters.
Major Durnovtsev's mission was to carry out the Soviet Union's 130th nuclear weapons test. The Tu-95 carried a single RDS-220, a three-stage radiation-implosion thermonuclear bomb. It was 8 meters (26.25 feet) long, with a diameter of 2.1 meters (6.89 feet), and weighed approximately 27,000 kilograms (59,525 pounds). The bomb was variously known as "Big Ivan" or "Tsar Bomba" (King of Bombs).
The Tu-95 dropped the RDS-220 from an altitude of 10,500 meters (34,449 feet) over the D-II test range, 15 kilometers (9 miles) north of the Mityushikha Strait on Novaya Zemlya. The bomb was retarded by parachute to allow the Bear time to escape the blast effects. After falling for 3 minutes, 8 seconds, at 11:33 a.m., the bomb detonated 4,000 meters (13,123 feet) above the surface of Novaya Zemlya. A bright flash of light lasted for 30 seconds and finally faded away after 70 seconds.
45 seconds after detonation, the nuclear cloud reached a height of 30 kilometers (19 miles), then spread outward, reaching a maximum diameter of 95 kilometers (59 miles).
Major Durnovtsev's Tu-95 was approximately 39 kilometers (24 miles) away for "ground zero" at the time of the explosion. As it continued to fly away from the blast, the shock waves finally caught up to bomber at a distance of 115 kilometers (71 miles), 8 minutes, 20 seconds after they had released the bomb.
At the same time, a secret United States Air Force Boeing JKC-135A Stratotanker instrumentation aircraft,
Speed Light Bravo, 55-3127, had flown closer to ground zero to gather data about the air burst. It was so close that its special anti-radiation paint was scorched. (55-3127 was later converted to the NKC-135A airborne laboratory configuration to support the Limited Test Ban Treaty of 1963. It was returned to tanker configuration in the 1980s. Later, 55-3127 served as a test bed aircraft for the Aeronautical Systems Division at Wright-Patterson It was retired to Davis-Monthan Air Force Base in 1992.)
After the nuclear explosion data was analyzed by the Foreign Weapons Evaluation Panel (the "Bethe Panel") the RDS-220 yield was estimated at 57 megatons. This was the largest nuclear weapon detonation in history. It was also the "cleanest," with 97% of the energy yield produced by fusion. Relative to the size of the explosion, very little fallout was produced.
All buildings in the town of Severny, 55 kilometers (34.2 miles) from Ground Zero, were destroyed. Wooden buildings as far as 200 kilometers (124 miles) were destroyed or heavily damaged.
A visible shock wave in the air was seen at a distance of 700 kilometers (435 miles). The shock wave from the explosion traveled around the world three times.
October 30, 2020 - This Day in Aviation