B61 bomb in various stages of assembly.

The B61 nuclear bomb is the primary thermonuclear weapon in the U.S. Enduring Stockpile following the end of the Cold War. A nuclear weapon is an explosive device that derives its destructive force from Nuclear reactions either fission or a combination of fission and fusion. Nuclear weapon designs are physical chemical and engineering arrangements that cause the physics package of a nuclear weapon to detonate The United States of America —commonly referred to as the The "Enduring Stockpile" is the United States 's arsenal of Nuclear weapons following the end of the Cold War. Cold War is the state of conflict tension and competition that existed between the United States and the Soviet Union (USSR and their respective allies from the

Development

A B61 bomb undergoing disassembly.

The B61, originally known (before 1968) as the TX-61, was designed in 1963. Year 1968 ( MCMLXVIII) was a Leap year starting on Monday (link will display full calendar of the Gregorian calendar. Year 1963 ( MCMLXIII) was a Common year starting on Tuesday (link will display full calendar of the Gregorian calendar. It was designed and built by the Los Alamos National Laboratory in New Mexico. Los Alamos National Laboratory (LANL (previously known at various times as Site Y, Los Alamos Laboratory, and Los Alamos Scientific Laboratory) is a New Mexico ( is a state located in the southwestern region of the United States of America. It began from a program for a lightweight, streamlined weapon launched in 1961. Year 1961 ( MCMLXI) was a Common year starting on Sunday (link will display full calendar of the Gregorian calendar. Production engineering began in 1965, with full production beginning in 1968 following a series of development problems. Year 1965 ( MCMLXV) was a Common year starting on Friday (link will display full calendar of the 1965 Gregorian calendar. Year 1968 ( MCMLXVIII) was a Leap year starting on Monday (link will display full calendar of the Gregorian calendar.

Total production of all versions was approximately 3,155, of which approximately 1,925 remain in service as of 2002, and some 1,265 are considered to be operational. See also 2002 (disambiguation Year 2002 ( MMII) was a Common year starting on Tuesday of the Gregorian calendar. The warhead has changed little over the years, although early versions have been upgraded to improve the safety features. Typically a warhead is the Explosive material and Detonator that is delivered by a Missile, Rocket, or Torpedo.

Nine versions (or 'Mods') of the B61 have been produced. Each shares the same 'physics package,' with different yield options. The explosive yield of a nuclear weapon is the amount of Energy, called the Yield, discharged when a Nuclear weapon is detonated expressed usually

The newest variant is the B61 Mod 11, deployed in 1997, which is a ground-penetrating bunker buster. Year 1997 ( MCMXCVII) was a Common year starting on Wednesday (link will display full 1997 Gregorian calendar Bunker-busting nuclear weapons, also known as earth-penetrating weapons (EPW, are a type of Nuclear weapon designed to penetrate into Soil, rock

The B61 gravity bomb should not be confused with the MGM-1 Matador cruise missile, which originally was developed under the bomber designation B-61. The Martin MGM-1 Matador was the first operational surface-to-surface Cruise missile built by the United States, similar in concept to the German A cruise missile is a guided Missile that carries an explosive payload and uses a lifting wing and a propulsion system usually a Jet engine, to allow

When the B61 was still classified, aircrew were not allowed to use the term "B61". Instead, it was referred to as a "shape", "silver bullet", or even "external delivery".

Deployment

The B61 has been deployed by a very wide variety of U. S. military aircraft. A military aircraft is any fixed-wing or rotary-wing Aircraft that is in the current employ of a Military power Aircraft cleared for its use have included the B-1, B-2, B-52, and FB-111 strategic bomber aircraft; the F-100 Super Sabre, F-104 Starfighter, F-105 Thunderchief, F-111 and F-4 Phantom II fighter bombers; the A-4 Skyhawk, A-6 Intruder, and A-7 Corsair II attack aircraft; the F-15 Eagle and F-15E Strike Eagle, F-16 Fighting Falcon, F/A-18 Hornet and Super Hornet; the Lockheed S-3 Viking; and the F-117 (although some sources claim the F-117 was never wired to carry nuclear weapons). WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout A strategic bomber is a heavy type Aircraft designed to drop large amounts of ordnance onto a distant target for the purposes of debilitating an enemy's A bomber is a Military aircraft designed to attack ground and sea targets primarily by dropping Bombs on them WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout WikipediaWikiProject Aircraft. Please see Wikipe diaWikiProject Aircraft/page content for recommended layout WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout Ground-attack aircraft are military aircraft designed to attack targets on the ground and are often deployed as Close air support for and in proximity to their own ground forces WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout Ground-attack aircraft are military aircraft designed to attack targets on the ground and are often deployed as Close air support for and in proximity to their own ground forces WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout The Lockheed Corporation (originally Loughead Aircraft Manufacturing Company was an American aerospace company founded in 1912 which merged with Martin Marietta WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout German and Italian Panavia Tornado IDS aircraft can also carry the B61. WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout

Though exact numbers are hard to establish, research done by the Natural Resources Defence Council suggests approximately 480 are deployed with United States Air Force units in various European countries. ^[1] The remainder are generally stored with the USAF's 898th Munitions Squadron at Kirtland Air Force Base and the 896th Munitions Squadron at Nellis Air Force Base. For the civil airport use of this facility see Albuquerque International Sunport Kirtland Air Force Base is a major United States Air Nellis Air Force Base is a United States Air Force base located in Clark County, Nevada.

Design

Internal nuclear components of the B61 bomb.

The B61 is a variable-yield bomb designed for carriage by high-speed aircraft. Variable yield, or dial-a-yield, an option available on most modern Nuclear weapons allows the operator to specify a weapon's yield, or explosive power It has a streamlined casing capable of withstanding supersonic flight speeds. The weapon is 11 ft 8 in (3. 58 m) long, with a diameter of about 13 in (33 cm). Basic weight is about 700 lb (320 kg), although the weights of individual weapons may vary depending on version and fuse/retardation configuration.

The newest variant is the B61 Mod 11, a hardened penetration bomb with a reinforced casing (according to some sources, containing depleted uranium) and a delayed-action fuze, allowing it to penetrate several metres into the ground before detonating, damaging fortified structures further underground [1]. Depleted uranium (DU is Uranium primarily composed of the Isotope Uranium-238 (U-238 In an Explosive, Pyrotechnic device or military Munition, a fuse (or fuze) is the part of the device that initiates function The Mod 11 weighs about 1,200 lb (540 kg). Developed from 1994, the Mod 11 went into service in 1997 replacing the older megaton-yield B53 bomb, a limited number of which had been retained for anti-fortification use. Year 1994 ( MCMXCIV) was a Common year starting on Saturday (link will display full 1994 Gregorian calendar) Year 1997 ( MCMXCVII) was a Common year starting on Wednesday (link will display full 1997 Gregorian calendar The B53 with a yield of 9 Mt is one of the most powerful Nuclear weapons built by the United States, and one of the last very high-yield thermonuclear About 50 Mod 11 bombs have been produced, their warheads converted from Mod 7 bombs. At present, the primary carrier for the B61 Mod 11 is the B-2 Spirit. WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout

Most versions of the B61 are equipped with a parachute retarder (currently a 24-ft (7. A parachute is a device used to slow the motion of an object through an atmosphere by creating drag. 3 m) diameter nylon/Kevlar chute) to slow the weapon in its descent, giving the aircraft a chance to escape the blast (or to allow the weapon to survive impact with the ground in laydown mode). Overview Nylon is a Thermoplastic silky material first used commercially in a nylon- Bristled Toothbrush (1938 followed more famously by Kevlar is the registered Trademark for a light strong para-aramid Synthetic fiber, related to other Aramids such as Nomex and Laydown delivery is a mode of deploying a free-fall Nuclear weapon in which the bomb's fall is slowed by Parachute so that it actually lands on the ground before The B61 can be set for airburst, ground burst, or laydown detonation, and can be released at speeds up to Mach 2 and altitudes as low as 50 feet (15 m). A groundburst is when an air-dropped Bomb explodes after hitting the ground Fusing for most versions is by radar. Radar is a system that uses electromagnetic waves to identify the range altitude direction or speed of both moving and fixed objects such as Aircraft, ships

The B61 is a variable-yield, kiloton-range weapon called "Full Fusing Option"(FUFO) or "Dial-a-yield" by many service personnel. Units of mass There are three similar units of Mass called the ton: Long ton (simply ton in countries such as the United Tactical versions (Mods 3, 4, and 10) can be set to 0. 3, 1. 5, 5, 10, 60, 80, or 170 kiloton explosive yield (depending on version). The strategic version (B61 Mod 7) has four yield options, with a maximum of 340 kilotons. Sources conflict on the yield of the earth-penetrating Mod 11; the physics package or bomb core components of the Mod 11 are apparently unchanged from the earlier strategic Mod 7, however the declassified 2001 Nuclear Posture Review [2] states that the B-61-11 has only a single yield; some sources indicate 10 KT, others suggest the 340 kiloton maximum yield as the Mod-7. Nuclear weapon designs are physical chemical and engineering arrangements that cause the physics package of a nuclear weapon to detonate

The early Mods 0, 1, 2, and 5 have been retired (Mods 6, 8, and 9 were cancelled before production), and the Mod 10 has been moved to the inactive stockpile, leaving the Mods 3, 4, 7, and 11 as the only variants in active service.

The U. S. is refurbishing the B61 bombs under its Life Extension Program with the intention that the weapons should remain operational until at least 2025. [3]

See also

B61s on a bomb rack.

• List of nuclear weapons
• B61 Family

References

External links

• "Developing and Producing the B-61", official AEC film
• B61 information at Carey Sublette's NuclearWeaponArchive.org
• B61 information at GlobalSecurity.org
• B61-11 Concerns and Background from the Los Alamos Study Group, an anti-nuclear weapons organization
• Low-Yield Earth-Penetrating Nuclear Weapons by Robert W. Nelson, Federation of American Scientists, January/February 2001, Volume 54, Number 1