The B83 is a variable-yield

thermonuclear Thermonuclear fusion is the process of atomic nuclei combining or “fusing” using high temperatures to drive them close enough together for this to become possible. There are two forms of thermonuclear fusion: ''uncontrolled'', in which the re ...

gravity bomb An unguided bomb, also known as a free-fall bomb, gravity bomb, dumb bomb, or iron bomb, is a conventional or nuclear aircraft-delivered bomb that does not contain a guidance system and hence simply follows a ballistic trajectory. This describe ...

developed by the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...

in the late 1970s that entered service in 1983. With a maximum yield of , it has been the most powerful nuclear weapon in the United States nuclear arsenal since October 25, 2011 after retirement of the B53. It was designed by

Lawrence Livermore National Laboratory Lawrence Livermore National Laboratory (LLNL) is a federal research facility in Livermore, California, United States. The lab was originally established as the University of California Radiation Laboratory, Livermore Branch in 1952 in response ...

History

The B83 was based partly on the earlier B77 program, which was terminated because of cost overruns. The B77 was designed with an active altitude control and lifting parachute system for supersonic low-altitude delivery from the

B-1A The Rockwell B-1 Lancer is a supersonic variable-sweep wing, heavy bomber used by the United States Air Force. It is commonly called the "Bone" (from "B-One"). It is one of three strategic bombers serving in the U.S. Air Force fleet along wit ...

bomber. B77 nuclear component test firings were attributed to the Operation Anvil series in 1975 and 1976, specifically the "Cheese" test shots in Anvil: * Anvil Kasseri – 28 October 1975, (B77/B83 full yield) * Anvil Muenster – 3 January 1976, * Anvil Fontina – 12 February 1976, * Anvil Colby – 14 May 1976, The B83 nuclear components have been attributed as the same as the earlier B77. The B83 replaced several earlier weapons, including the B28, B43, and to some extent the 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 explosives" in the trigger lens system. Its layout is similar to that of the smaller B61, with the

warhead A warhead is the forward section of a device that contains the explosive agent or toxic (biological, chemical, or nuclear) material that is delivered by a missile, rocket, torpedo, or bomb. Classification Types of warheads include: * Explosiv ...

mounted in the forward part of the weapon to make the bomb nose-heavy. It was intended for high-speed carriage (up to Mach 2.0) and delivery at high or low altitude. For the latter role, it is equipped with a parachute retardation system, with a

Kevlar Kevlar (para-aramid) is a strong, heat-resistant synthetic fiber, related to other aramids such as Nomex and Technora. Developed by Stephanie Kwolek at DuPont in 1965, the high-strength material was first used commercially in the early 1970s a ...

ribbon parachute A parachute is a device used to slow the motion of an object through an atmosphere by creating drag or, in a ram-air parachute, aerodynamic lift. A major application is to support people, for recreation or as a safety device for aviators, who ...

capable of rapid deceleration. It can be employed in free-fall, retarded, contact, and

laydown Laydown delivery is a mode of delivery found in some nuclear gravity bombs: the bomb's descent to the target is slowed by parachute so that it lands on the ground without detonating. The bomb then detonates by timer some time later. Laydown deliver ...

modes, for air-burst or ground-burst detonation. Security features include next-generation

permissive action link A permissive action link (PAL) is an access control security device for nuclear weapons. Its purpose is to prevent unauthorized arming or detonation of a nuclear weapon. The United States Department of Defense definition is: The earliest PALs ...

(PAL) and a command disablement system (CDS), rendering the weapon tactically useless without a nuclear yield. The B83 was test fired in the Grenadier Tierra nuclear weapon test on 15 December 1984, at a reduced yield of 80 kilotonnes due to the

Threshold Test Ban Treaty The Treaty on the Limitation of Underground Nuclear Weapon Tests, also known as the Threshold Test Ban Treaty (TTBT), was signed in July 1974 by the United States and Soviet Union. It establishes a nuclear "threshold" by prohibiting nuclear tests ...

. With the dismantling of the last B53 bomb in 2011, the B83 became the highest yield nuclear weapon in the U.S. arsenal. In 2022, Biden administration declared that they plan to retire B83.

Design

The bomb is long, with a diameter of . The actual nuclear explosive package, judging from published drawings, occupies some in the forward part of the bomb case. The bomb weighs approximately . The location of the lifting lugs shows that the greater part of the total mass is contained in the nuclear explosive. It has a

variable yield Variable yield, or dial-a-yield, is an option available on most modern nuclear weapons. It allows the operator to specify a weapon's yield, or explosive power, allowing a single design to be used in different situations. For example, the Mod-10 ...

: the destructive power is adjustable from somewhere in the low

kiloton TNT equivalent is a convention for expressing energy, typically used to describe the energy released in an explosion. The is a unit of energy defined by that convention to be , which is the approximate energy released in the detonation of a t ...

range up to a maximum of . The weapon is protected by a Category "D" Permissive Action Link (PAL) that prevents the enabling or detonation of the weapon without proper authorization. About 650 B83s were built, and the weapon remains in service as part of the United States "

Enduring Stockpile The Enduring Stockpile is the United States' arsenal of nuclear weapons following the end of the Cold War. During the Cold War the United States produced over 70,000 nuclear weapons. By its end, the U.S. stockpile was about 23,000 weapons of 26 ...

Aircraft capable of carrying the B83

The following aircraft are certified for carrying the B83 bomb: *

B-52 Stratofortress The Boeing B-52 Stratofortress is an American long-range, subsonic, jet-powered strategic bomber. The B-52 was designed and built by Boeing, which has continued to provide support and upgrades. It has been operated by the United States Air ...

(formerly) *

B-1B Lancer The Rockwell B-1 Lancer is a supersonic variable-sweep wing, heavy bomber used by the United States Air Force. It is commonly called the "Bone" (from "B-One"). It is one of three strategic bombers serving in the U.S. Air Force fleet along with ...

(formerly) *

B-2 Spirit The Northrop (later Northrop Grumman) B-2 Spirit, also known as the Stealth Bomber, is an American heavy strategic bomber, featuring low-observable stealth technology designed to penetrate dense anti-aircraft defenses. A subsonic flying ...

Nuclear capability has been removed from the B-1B, and the B-52 no longer carries gravity nuclear bombs.

Novel uses

The B83 is one of the weapons considered for use in the "

Nuclear Bunker Buster A nuclear bunker buster, also known as an earth-penetrating weapon (EPW), is the nuclear equivalent of the conventional bunker buster. The non-nuclear component of the weapon is designed to penetrate soil, rock, or concrete to deliver a nuclear ...

" project, which for a time was known as the Robust Nuclear Earth Penetrator, or RNEP. While most efforts have focused on the smaller B61-11 nuclear bomb,

Los Alamos National Laboratory Los Alamos National Laboratory (often shortened as Los Alamos and LANL) is one of the sixteen research and development laboratories of the United States Department of Energy (DOE), located a short distance northwest of Santa Fe, New Mexico, ...

was also analyzing the use of the B83 in this role. The

physics package Nuclear weapon designs are physical, chemical, and engineering arrangements that cause the physics package of a nuclear weapon to detonate. There are three existing basic design types: * pure fission weapons, the simplest and least technically ...

contained within the B83 has been studied for use in

asteroid impact avoidance Asteroid impact avoidance comprises the methods by which near-Earth objects (NEO) on a potential collision course with Earth could be diverted away, preventing destructive impact events. An impact by a sufficiently large asteroid or other NEOs ...

strategies against any seriously threatening near earth asteroids. Six such warheads, configured for the maximum , would be deployed by maneuvering space vehicles to "knock" an asteroid off course, should it pose a risk to the Earth. (article at Flightglobal.com)

References

External links