B53 Nuclear Weapon

Almost as big as a minivan and weighing over four tons, the B53 was America's largest conventionally dropped nuclear bomb. The mammoth B53 had a yield of 9 megatons—enough to create a fireball nearly 3 miles in diameter.

The weapon was developed in 1955 and originally designed as a "bunker buster." With reports of Soviet command and control centers deep underground, the new bomb had to be powerful enough to generate a massive shock wave that would collapse these hidden structures. Buildings at surface level fared even worse; tests showed that a B53 blast would level most residential and industrial structures more than nine miles from the detonation point. While incredibly destructive only about 340 of these bombs were produced, though they did serve as the inspiration for the W-53 warhead on the Titan II missile.

First produced in 1962, the massive bomb could be carried by most large Cold War era bombers, including the Boeing B-52 and the supersonic Convair B-58.

The bomb was equipped for “laydown-delivery” in which a series of parachutes slow its fall. This allows the bomb to make solf contact with the ground before detonating, ensuring maximum destrucion of underground targets. The weapon could also be set to freefall and explode above a target.

At the time of its retirement in 2010, the B53 was America’s oldest and highest-yield thermonuclear weapon. The B53 was 600 times as powerful as the atomic bomb dropped on Hiroshima.

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