The W80 is a low to intermediate yield two-stage

thermonuclear warhead A thermonuclear weapon, fusion weapon or hydrogen bomb (H bomb) is a second-generation nuclear weapon design. Its greater sophistication affords it vastly greater destructive power than first-generation nuclear bombs, a more compact size, a low ...

deployed by the U.S.

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 ...

with 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 ...

("dial-a-yield") of . It was designed for deployment on

cruise missile A cruise missile is a guided missile used against terrestrial or naval targets that remains in the atmosphere and flies the major portion of its flight path at approximately constant speed. Cruise missiles are designed to deliver a large warhe ...

s and is the warhead used in all nuclear-armed ALCM and ACM missiles deployed by the

US Air Force The United States Air Force (USAF) is the air service branch of the United States Armed Forces, and is one of the eight uniformed services of the United States. Originally created on 1 August 1907, as a part of the United States Army Signal ...

, and in the

US Navy The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage of ...

BGM-109 Tomahawk The Tomahawk () Land Attack Missile (TLAM) is a long-range, all-weather, jet-powered, subsonic cruise missile that is primarily used by the United States Navy and Royal Navy in ship and submarine-based land-attack operations. Under contract f ...

. It is essentially a modification of the widely deployed B61 weapon, which forms the basis of most of the current US stockpile of nuclear gravity bombs. The very similar

W84 The W84 is an American thermonuclear warhead initially designed for use on the BGM-109G Gryphon Ground Launched Cruise Missile (GLCM). History The weapon was designed by Lawrence Livermore National Laboratory beginning in September 1978 for th ...

warhead was deployed on the retired

BGM-109G Ground Launched Cruise Missile The Ground Launched Cruise Missile, or GLCM, (officially designated BGM-109G Gryphon) was a ground-launched cruise missile developed by the United States Air Force in the last decade of the Cold War and disarmed under the INF Treaty. Overview ...

Dimensions

The W80 is physically quite small: 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 ...

itself is about the size of a conventional Mk.81 bomb, in diameter and long, and only slightly heavier at about .

History

Early development

The

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, ...

began development on the W80 in June 1976, with the brief of producing a custom weapon for the

s then under construction. With "the basic design" being derived from the B61. The main design differences are presumably a smaller secondary producing only yield (the B61 producing a maximum of in the tactical variants and in the strategic variants) and simplification of the design giving the weapon only two yield settings; . Production of the W80 mod 1 (W80-1) to arm the ALCM started in January 1979, and a number of warheads had been completed by January 1981 when the first low-temperature test was carried out. To everyone's surprise the test delivered a much lower yield than was expected, apparently due to problems in the

TATB TATB, triaminotrinitrobenzene or 2,4,6-triamino-1,3,5-trinitrobenzene is an aromatic explosive, based on the basic six-carbon benzene ring structure with three nitro functional groups (NO2) and three amine (NH2) groups attached, alternating aroun ...

based

insensitive high explosive Insensitive munitions are munitions that are designed to withstand stimuli representative of severe but credible accidents. The current range of stimuli are shock (from bullets, fragments and shaped charge jets), heat (from fires or adjacent ther ...

s used to fire the primary. This problem turned out to affect several models of the B61-based line, and production of all weapons was suspended while a solution was worked on. Production restarted in February 1982. In March 1982, designers began working on a W80 variant intended for the Navy's

Tomahawk A tomahawk is a type of single-handed axe used by the many Indigenous peoples and nations of North America. It traditionally resembles a hatchet with a straight shaft. In pre-colonial times the head was made of stone, bone, or antler, and Europ ...

program. The W80 mod 0 (W80-0) used "supergrade" fission fuel, which has less radioactivity, in the primary in place of the conventional

plutonium Plutonium is a radioactive chemical element with the symbol Pu and atomic number 94. It is an actinide metal of silvery-gray appearance that tarnishes when exposed to air, and forms a dull coating when oxidized. The element normally exhibi ...

used in the Air Force's version. "Supergrade" is industry

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