B83 nuclear bomb

From Wikipedia, the free encyclopedia

The B83 nuclear gravity bomb

The B83 nuclear weapon is a variable-yield gravity bomb developed by the United States in the late 1970s, entering service in 1983. It was based partly on the earlier B77 program, which was terminated due to cost overruns. The first underground test detonation took place on 15 December 1984. Development took place at the Lawrence Livermore National Laboratory.

The B83 replaced several earlier weapons, including the B28, B43, and ultra-high yield B53. It was the first U.S. nuclear weapon designed from the start to avoid accidental detonation, with the use of 'insensitive' explosive in the trigger lens system. Its internal design and layout are similar to the smaller B61, with the warhead mounted in the forward part of the weapon to make the bomb deliberately nose-heavy. It was intended for high-speed carriage (up to Mach 2.0) and delivery at either high or low altitude. For the latter role, it can be equipped with a parachute retardation system, with a 46 ft (14 m) Kevlar parachute capable of rapid deceleration. It can be employed in free fall, retarded, contact, or laydown modes, for either airburst or ground burst detonation.

The bomb is 12 ft (3.67 m) long, with a diameter of 18 in (457 mm). It weighs approximately 2,400 lb (1,089 kg). Maximum yield is 1.2 megatons.

A B83 casing.

The B83 can be deployed by a wide range of U.S. aircraft including:

About 650 B83s were built, and the weapon remains in service as part of the United States "Enduring Stockpile."

[edit] Earth-penetrating warheads

The B83 is one of the weapons which has been considered for use in the Robust nuclear earth penetrator program, otherwise known as Nuclear bunker buster. While most efforts have focused on the smaller B61-11 nuclear bomb, Lawrence Livermore National Laboratory was also analyzing the use of the B83 in this role.

As of early 2006, the RNEP program has been halted by congress.