Friday, November 6, 2015

B61 Nuclear Bomb

B61 Nuclear Bomb ---


The 700 lb B61 is the only tactical nuclear bomb in the U.S. arsenal. ... the right altitude to explode; it is an old model that still uses vacuum tubes.

$8 billion upgrade to the B61 nuclear bomb.

B61 bombs that have vacuum tubes in their radar-fuses account for only about one in ten operationally deployed warheads

Engineers have resorted to scouring EBay to replace circuits and vacuum tubes to keep the bombs operational.

*Reference

B61 nuclear bomb - Wikipedia, the free encyclopedia
WikipediaThe B61 nuclear bomb is one of the primary thermonuclear weapons in the U.S. Enduring Stockpile following the end of the Cold War. It is an intermediate-yield ...
Blast yield‎: ‎0.3–340 kilotons
Designer‎: ‎Los Alamos National Laboratory
Used by‎: ‎United States
Designed‎: ‎1963

B61 Family - Wikipedia, the free encyclopedia
WikipediaJump to Bomb - Bomb[edit]. The overall B61 bomb was 13.3 inches (340 mm) diameter by 141 inches (3,600 mm) long, and weighed 695-715 pounds ...


From PBS News Hour

Photos: What an $8B nuclear bomb upgrade looks like

BY DAN SAGALYN  November 5, 2015 at 4:31 PM EST
PBS NewsHour cameraman Jay Olivier filming Senior Mechanical Engineer Jeremy McCord at the Department of Energy’s National Security Campus outside Kansas City, Missouri. Photo by Dan Sagalyn
PBS NewsHour cameraman Jay Olivier filming Senior Mechanical Engineer Jeremy McCord at the Department of Energy’s National Security Campus outside Kansas City, Missouri, one of the facilities in the U.S. government’s $8 billion upgrade of the B61 bomb. Photo by Dan Sagalyn
Designing and building nuclear bombs is one of the U.S. government’s most secretive activities. But the PBS NewsHour recently was granted unprecedented access to a number of highly classified facilities, where the world’s most destructive weapons are now being updated and rebuilt.
The Department of Energy — which is responsible for maintaining the atomic stockpile — plans to spend $100 billion over the next decade rebuilding its production facilities and refitting nuclear weapons with modernized parts. Department officials say their goal is to replace the components in nuclear weapons that have aged, improve their safety, and streamline the stockpile by reducing the number of different bomb models in inventory.
Below, see photos of one particular project, the $8 billion upgrade to the B61 nuclear bomb. Watch the PBS NewsHour’s full report tonight.
At center, the device holding the middle section of this B61-12 nuclear bomb was designed to allow technicians to safely move around different parts of the bomb without using hoists. Senior Mechanical Engineer Jeremy McCord at the Energy Department’s National Security Campus outside Kansas City designed and built this Assembly Tooling Lifting Alignment System, or “ATLAS.” Photo by Dan Sagalyn
At center, the device holding the middle section of this B61-12 nuclear bomb was designed to allow technicians to safely move around different parts of the bomb without using hoists. Senior Mechanical Engineer Jeremy McCord at the Energy Department’s National Security Campus outside Kansas City designed and built this Assembly Tooling Lifting Alignment System, or “ATLAS.” Photo by Dan Sagalyn
A scanner at the National Security Campus outside Kansas City shines blue light onto a part, taking precise measurements that provide data for building a blueprint. The data is fed into a 3-D printer to reproduce the item. Parts that were made decades ago and are currently in nuclear bombs can be scanned and remade using this technology. Photo by Dan Sagalyn
A scanner at the National Security Campus outside Kansas City shines blue light onto a part, taking precise measurements that provide data for building a blueprint. The data is fed into a 3-D printer to reproduce the item. Parts that were made decades ago and are currently in nuclear bombs can be scanned and remade using this technology. Photo by Dan Sagalyn
Vacuum tubes and other older technologies in the B61 will be replaced by this newly designed printed circuit board.  Photo by Dan Sagalyn
Vacuum tubes and other older technologies in the B61 will be replaced by this newly designed printed circuit board. Photo by Dan Sagalyn
Sandia’s Senior Manager for the B61-12 Brad Boswell, left, with Jamie McIntyre, Al Jazeera America’s national security correspondent on special assignment for the PBS NewsHour. The mock-ups of the old B61-4 nuclear bomb, left, and the refurbished B61-12 bomb, right, look similar. The first production model of the B61-12 is scheduled to be fielded in 2020. It will be a “modernized version of the old bomb, where we are meeting the military requirements while looking for opportunities to improve the safety and the security of the weapon,” Boswell told McIntyre. One improvement is swapping out old-fashioned parts such as vacuum tubes, located in the bomb’s radar system, for modern electronics. Photo by Dan Sagalyn
Sandia’s Senior Manager for the B61-12 Brad Boswell, left, with Jamie McIntyre, Al Jazeera America’s national security correspondent on special assignment for the PBS NewsHour. The mock-ups of the old B61-4 nuclear bomb, left, and the refurbished B61-12 bomb, right, look similar. The first production model of the B61-12 is scheduled to be fielded in 2020. It will be a “modernized version of the old bomb, where we are meeting the military requirements while looking for opportunities to improve the safety and the security of the weapon,” Boswell told McIntyre. One improvement is swapping out old-fashioned parts such as vacuum tubes, located in the bomb’s radar system, for modern electronics. Photo by Dan Sagalyn
One major difference between the old B61 and the new version of the bomb, above, is the tail fins. On the old B61, the fins were welded and screwed in place. The B61-12’s tail fins move. Using inertial navigation, the bomb is guided to its target. Critics say the new tail kit and other enhancements effectively make the B61 a whole new nuclear bomb. These critics say the B61-12’s new capabilities are a violation of President Obama’s 2010 pledge to not introduce new military capabilities into the nuclear arsenal. Photo by Dan Sagalyn
One major difference between the old B61 and the new version of the bomb, above, is the tail fins. On the old B61, the fins were welded and screwed in place. The B61-12’s tail fins move. Using inertial navigation, the bomb is guided to its target. Critics say the new tail kit and other enhancements effectively make the B61 a whole new nuclear bomb. These critics say the B61-12’s new capabilities are a violation of President Obama’s 2010 pledge to not introduce new military capabilities into the nuclear arsenal. Photo by Dan Sagalyn
Prototype of a B61-12 on an F-15E aircraft at Eglin Air Force Base in Florida. Photo by Dan Sgalyn
Prototype of a B61-12 on an F-15E aircraft at Eglin Air Force Base in Florida. Photo by Dan Sgalyn
This story was produced in partnership with the Pulitzer Center on Crisis Reporting.



*Vacuum Tubes

The RRW's vacuum tube myth | Bulletin of the Atomic ...
thebulletin.org/rrws-vacuum-tube-myth
Bulletin of the Atomic ScientistsApr 22, 2009 - Lewis is director of the Nuclear Strategy and Nonproliferation. ... In total, the B61 bombs that have vacuum tubes in their radar-fuses account for ...

The B61 bomb: A case study in needs and costs - The ...
https://www.washingtonpost.com/...b61-bomb.../494a...
The Washington PostSep 16, 2012 - The redesign of the B61 bomb, the oldest nuclear weapon, offers a ...as the vacuum tubes needed to keep the radars working on active bombs.

Photos: What an $8B nuclear bomb upgrade looks like - PBS
www.pbs.org/newshour/.../8b-nuclear-bomb-upgrade-looks-like/
PBS17 hours ago - Designing and building nuclear bombs is one of the U.S. ... Vacuum tubes and other older technologies in the B61 will be replaced by this ...

Jeffrey Lewis • B61 Replacement and Vacuum Tubes
lewis.armscontrolwonk.com/archive/.../b61-replacement-and-vacuum-tu...
Sep 15, 2009 - We pointed out in the Bulletin of Atomic Scientists that vacuum tubesare .... boosted fission bomb, while the b61 is a thermonuclear (in most ...

Jeffrey Lewis • Vacuum Tubes
lewis.armscontrolwonk.com/archive/2266/vacuum-tubes
Apr 23, 2009 - In total, the B61 bombs that have vacuum tubes in their radar-fuses .....We are talking about massively destructive nuclear weapons, after all. 2.

New Atomic Bomb to Reduce US Nuclear Arsenal by Type ...
sputniknews.com/us/20150710/1024473663.html
Jul 10, 2015 - The new B61-12 atomic gravity bomb will replace four earlier ... prove the viability of microchip technology to replace older vacuum tubes, and a ...

B61-12 Life Extension Program Radar Drop Tests ...
nnsa.energy.gov/.../droptest082...
National Nuclear Security AdministrationAug 29, 2013 - Current B61s use decades-old vacuum tubes as part of their radar system. ... “As long as the United States continues to have nuclear weapons, ...

Better Nuclear Bombs for a Safer World - Bloomberg View
www.Dec 25, 2012 - As wonderful as the idea of a world without nuclear weapons is, it isn't going to ... The B61's utility in this regard comes from its so-called dial-a-yield ...

What needs improving? One weapons manager told the Washington Post that the entire arsenal was built with less computational power than that of an iPhone. Engineers have resorted to scouring EBay to replace circuits and vacuum tubes to keep the bombs operational. The first stage of proposed modernization will be to give the bomb a new tail kit similar to that of up-to-date precision-guided missiles, for which Boeing Co. received a $178 million contract in November. The entire upgrade -- in which the four current variations of the B61 will be morphed into a single, maximally flexible bomb -- will take three years.

Opponents of the program, mostly well-meaning but misguided arms-control advocates, have taken two lines of attack. One is to point out that most B61s are deployed in Europe -- even though the Soviet threat disappeared long ago. Two responses: First, the North Atlantic Treaty Organization allies’ involvement in their own nuclear defense binds together a vital organization in an era of increasingly fragile ties. Second, geography isn’t very relevant as the weapons can be moved around the globe quickly: A B61 in the bomb bay of a B-2 based in Missouri can quickly be a threat, and thus a deterrent, to North Korea and China.

Uncategorized | Nuclear Dreams | Page 2
https://nucleardreams.wordpress.com/category/uncategorized/page/2/
In total, the B61 bombs that have vacuum tubes in their radar-fuses account for only about one in ten operationally deployed warheads. (Vacuum tubes are used ...

Rising Costs for B61 Prompt Questions | Arms Control ...
https://www.armscontrol.org/.../Rising-Costs-fo...
Arms Control AssociationDec 4, 2012 - The B61 is the only tactical nuclear bomb in the U.S. arsenal. ... the right altitude to explode; it is an old model that still uses vacuum tubes.

*wikipedia 11/6/2015

B61 nuclear bomb

From Wikipedia, the free encyclopedia
B61
B-61 bomb.jpg
B61 training unit intended for ground crew. It accurately replicates the shape and size of a "live" B61 (together with its safety/arming mechanisms) but contains only inert materials
TypeNuclear bomb
Service history
Used byUnited States
Production history
DesignerLos Alamos National Laboratory
Designed1963
ManufacturerPantex Plant
Produced1968 (full production)
Number built3,155
Specifications
Weight700 pounds (320 kg)
Length11 feet 8 inches (3.56 m)
Diameter13 inches (33 cm)

Blast yield0.3–340 kilotons
The B61 nuclear bomb is one of the primary thermonuclear weapons in the U.S. Enduring Stockpile following the end of the Cold War. It is an intermediate-yield strategic and tactical nuclear weapon featuring a two-stage radiation implosion design.[1]
The B61 is a variable yield bomb (0.3 to 340 kiloton yield in various versions and settings) designed for carriage by high-speed aircraft. 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 fuze/retardation configuration.

Development[edit]


A B61 bomb undergoing disassembly.
The B61, known before 1968 as the TX-61, was designed in 1963. It was designed and built by the Los Alamos National Laboratory in New Mexico. It began from a program for a lightweight, streamlined weapon launched in 1961. Production engineering began in 1965, with full production beginning in 1968 following a series of development problems.
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.[citation needed] The warhead has changed little over the years, although early versions have been upgraded to improve the safety features.[citation needed]
As of late 2013, there were 200 B61 bombs actively in use by the United States.[2] Of these, 180 were deployed with NATO allies in Europe.[3]
Nine versions of the B61 have been produced. Each shares the same "physics package", with different yield options.The newest variant is the B61 Mod 11, deployed in 1997, which is a ground-penetrating bunker buster.
The Russian Continuity of Operations facility at Kosvinsky Kamen, finished in early 1996, was designed to resist US earth-penetrating warheads and serves a similar role as the American Cheyenne Mountain Complex.[4][5] The timing of the Kosvinsky completion date is regarded as one explanation for U.S. interest in a new nuclear bunker buster and the declaration of the deployment of the B-61 mod 11 in 1997: Kosvinsky is protected by about 1,000 feet (300 m) of granite.[6]
The B61 unguided bomb should not be confused with the MGM-1 Matador cruise missile, which was originally developed under the bomber designation B-61.
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[edit]


B61 bomb in various stages of assembly. The nuclear component is contained in the small, silver cylinder near the upper middle
The B61 has been deployed by a variety of U.S. military aircraft. Aircraft cleared for its use have included the FB-111AB-1 Lancer, B-2 Spirit, B-52 Stratofortress; F-101 VoodooF-100 D & F Super SabreF-104 Starfighter,F/A-18 HornetF-111 Aardvark and F-4 Phantom II fighter bombersA-4 SkyhawkA-6 Intruder and A-7 Corsair II attack aircraft; the F-15 EagleF-15E Strike Eagle and F-16 FalconBritishGerman and Italian Panavia Tornado IDS aircraft. USAFE and all NATO dual role aircraft can carry B61s. The Lockheed S-3 Viking was also able to deploy the B61 as a nuclear depth bomb.
The B61 cannot fit inside the F-22 Raptor's weapons bays and will instead be carried by the Lockheed Martin F-35 Lightning II.[7]
Though exact numbers are hard to establish, research done by the Natural Resources Defense Council suggests approximately 180 are deployed with United States Air Force Europe units.[8]
As of 2005, they were deployed in Europe under the NATO nuclear sharing arrangement.[9] NATO has agreed to vastly improve the capabilities of this force with the increased accuracy of the B61 Mod 12 upgrade and the stealthy delivery of the F-35.[10][11] This will for the first time add a modest standoff capability to the B61.[12]

Mod 12[edit]

As of 2013, the Pentagon was asking for an $11 billion life-extension program for the B61 bomb, which would be the most ambitious and expensive nuclear warhead refurbishment in history. Congress is opposed to this effort for cost and timeline issues and questions for the B61's need. Cost estimates have doubled from $4 billion to $8 billion and production slipped from 2017 to 2020, then grew to $10 billion for life extension plus $1 billion for tail guidance kits and production was delayed to 2021. Sequestration budget cuts in early 2013 have delayed any start until 2020. The Senate Energy and Water Appropriations Subcommittee stated that extending the life of B61s and consolidating its variants may not be a cheap and low-risk method to meet military requirements.
The B61 Mod 12 is to replace the previous Mod 3, 4, 7, and 10 versions with 400–500 planned with a service life of 20 years. Refurbishing the existing variants and eliminating the guidance kit would save $2–3 billion. There are also questions about the future structure of gravity nuclear bombs. European deployments of warheads by NATO countries are cited as a reason for the low-yield Mod 12. With reductions planned of nuclear weapons in Europe, which may retire the older Mod 3 and 4 and the Mod 10 already slated for retirement, and the possibility that European nations may not build or procure new aircraft to carry the Mod 12 would eliminate the need for consolidation into a new type. Congressman John Garamendi has suggested that the B61 simply be retired and the B83 nuclear bomb be used instead.
While the B61 was first developed in the 1950s and 1960s, the B83 entered service in 1983. The National Nuclear Security Administration, the Pentagon, and the Air Force have called the B83 a "relic of the Cold War" and believe that deploying a megaton-yield gravity bomb, the highest level nuclear weapon left in the U.S. inventory, to Europe is "inconceivable" at this point. The B61-12 is being pursued as a forward-deployed tactical nuclear weapon to protect NATO and Asian allies, and having a credible American nuclear deterrent may dissuade allies from developing their own nuclear weapons. While the B83 can only arm the B-2 Spirit bomber, the B61-12 can enhance accuracy from it and be deployed from dual-capable fighter aircraft, as well as planned to arm the F-35 and Long Range Strike Bomber; the B83 is not compatible with NATO aircraft or any other U.S. fighters.
The Air Force says that upgrading the B61 would be "considerably" less expensive than integrating the B83 to additional aircraft. Having a megaton yield that can't be as varied as the B61 also makes it less flexible and the Air Force is pushing for warheads that would have less collateral effects. Recapitalizing the B61 is hoped to lead to the retirement of the B83 to comply with plans for fewer, safer, and more reliable warheads. Retirement of the B83 would result in the elimination of the last megaton-yield U.S. bomb and leave the B61-series as the only U.S. gravity nuclear bomb.
The Pentagon and NNSA have stated that if B61 refurbishment does not begin by 2019, components in the existing weapons could begin to fail.[13][14] Tom Collina of the Arms Control Association has said that the new development could complicate arms control efforts with Russia.[15] In 2014 Congress slashed funding for the project and called for alternates to be studied.[16]
In January 2014, former Air Force Chief of Staff Norton Schwartz confirmed that the B61-12 nuclear bomb upgrade would have enhanced accuracy and a lower yield with less fallout compared to previous versions of the weapon. Accuracy has not been a guarantee for air-dropped nuclear weapons, so consequently large warheads were needed to effectively impact a target; the B61-11 nuclear earth-penetrator is accurate to 110–170 meters from the desired detonation location, so it requires a 400-kiloton warhead. The B61-12 is accurate to 30 meters from a target and only requires a 50-kiloton warhead. Schwartz believes that greater accuracy would both improve the weapon and create a different target set it can be useful against. An example is the higher-yield B61-11's role of attacking underground bunkers that need a ground burst to create a crater and destroy it through the shockwave. A 50-kiloton yield detonating on the ground produces a crater with a radius of 30–68 meters, depending on the density of the surface, effectively putting the bunker within the circular error probability.
Critics say that a more accurate and less destructive nuclear weapon would make leaders less cautious about deploying it, but Schwartz says it would deter adversaries more because the U.S. would be more willing to use it in situations where necessary. The B61-12 is also important for modernization of European nuclear stocks. The improved accuracy makes it more effective than the previous B61-3/4 currently deployed to the continent. F-16 and Panavia Tornado aircraft cannot interface with the new bomb due to electronic differences, but NATO countries that are buying the F-35 will be able to utilize it.[17]
The first flight test for an inert B61-12 was conducted in 2015.[18][19]

Design[edit]


Inert training version of a B61 in an underground Weapons Storage and Security System (WS3) vault at Volkel Air Base, Netherlands. An access panel on the warhead is open, showing the interface for actions such as PAL (safety/arming) and variable yieldsetting

Internal nuclear components of the B61 bomb. The bomb was assembled at the Burlington AEC Plant and Pantex.
The B61 is a variable yield bomb designed for carriage by high-speed aircraft. 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 fuze/retardation configuration.
B61 administrative procedures performed by ground-based personnel are executed via an access panel located on the side of the bomb, which opens to reveal 9 dials, 2 sockets and a T-handle which manually triggers the "command disable" function. One of the sockets is a MC4142 "strike enable" plug which must be inserted in order to complete critical circuits in the safety/arming and firing mechanisms. The other socket is the PAL connector located in the top right hand corner of the arming panel, which has 23 pins marked with alphabetic letter codes.
The B61 also features a "command disable" mechanism, which functions as follows: after entering the correct 3-digit numeric code it is then possible to turn a dial to "DI" and pull back a T-shaped handle which comes away in the user's hand. This action releases a spring-loaded firing pin which fires the percussion cap on an MC4246A thermal battery, powering it up. Electrical power from the thermal battery is sufficient to "fry" the internal circuitry of the bomb, destroying critical mechanisms without causing detonation. This makes the bomb incapable of being used. Any B61 which has had the command disable facility used must be returned to Pantex for repair.[20]
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.[21] 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-yieldB53 bomb. 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.
Most versions of the B61 are equipped with a parachute retarder (currently a 24-ft (7.3 m) diameter nylon/Kevlar chute) to slow the weapon in its descent. This offers the aircraft a chance to escape the blast, or allows the weapon to survive impact with the ground in laydown mode. 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).
The B61 is a variable yield, kiloton-range weapon called "Full Fuzing Option"(FUFO) or "Dial-a-yield" by many service personnel. Tactical versions (Mods 34, and 10) can be set to 0.3, 1.5, 5, 10, 45, 60, 80, or 170 kiloton explosive yield (depending on version).[22] 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[23] 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.
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. intended to refurbish the B61 bombs under its Life Extension Program with the intention that the weapons should remain operational until at least 2025.[24] However, the United States Congress ordered that this work be stopped, pending reports from the National Academy of Sciences and JASON defense advisory panel.[25]
In May 2010 the National Nuclear Security Administration asked Congress for $40 million to redesign the bomb to enable the Lockheed Martin F-35 Lightning II to carry the weapon internally by 2017.[26] This version is designated Mod 12.[27] The four hundred B61-12 bombs will be used by both tactical aircraft (such as the F-35) and strategic aircraft (such as the B-2) and the Tail Subassembly (TSA) will give them Joint Direct Attack Munitionlevels of accuracy, allowing the fifty kiloton warhead to have strategic effects from all carrying aircraft.[28] However, refitting the 400 weapons is now expected to cost over $10 billion.[29] The B61 Mod 12 tail assembly contract was awarded to Boeing on November 27, 2012 for $178 million.[30] Boeing will use their experience with the Joint Direct Attack Munition to yield JDAM equivalent accuracy in a nuclear bomb.[31] This contract is only the first part of the billion dollar expense of producing and applying the tail kits, over and above the $10 billion cost to refurbish the warheads.[32] The B61-12 uses an internal guidance system and can glide to its target. The bomb has four selectable yields: 0.3; 5; 10; and 50 kilotons.[33] On 1 July 2015, the National Nuclear Security Administration (NNSA) conducted the first of three flight tests of the B61-12 tail kit assembly.[34]

See also[edit]


B61s on a bomb rack.

References[edit]

  1. Jump up^ Sublette, Carey (9 January 2007). "The B61 Bomb". Nuclear weapon archive. Retrieved 2012-06-09.
    Jump up^ "Physics Today", September 2013, page 45
    Jump up^ "The Bulletin of the Atomic Scientists", 26 October 2013
    Jump up^ "Window on Heartland: Geopolitical notes on Eastern Europe, the Caucasus and Central Asia". Feb 2012. Archived from the original on Apr 24, 2013.
    Jump up^ Gertz, William ‘Bill’ (April 1, 1997), "Moscow builds bunkers against nuclear attack", The Washington Times (Global security).
    Jump up^ "Kosvinsky Mountain, Kos'vinskiy Kamen', Gora, MT 59°31'00"N 59°04'00"E, Russia". Global Security. |= ignored (help)
    Jump up^ Grant, Rebecca. "Nukes for NATO." Airforce Magazine, July 2010
    Jump up^ Hans M. Kristensen/Natural Resources Defense Council, U.S. Nuclear weapons in Europe (2005), article retrieved December 21, 2007.
    Jump up^ "US nukes to stay in Germany – media". Russia Today. 6 September 2012.
    Jump up^ Kristensen, Hans M. "New Report: US and Russian Non-Strategic Nuclear Weapons." Federation of American Scientists, 2 May 2012.
    Jump up^ Borger, Julian (21 April 2013). "Obama accused of nuclear U-turn as guided weapons plan emerges". The Guardian. Retrieved 11 June 2013.
    Jump up^ Kristensen, Hans M. (30 October 2013). "Capabilities of B61-12 Nuclear Bomb Increase Further". Federation of American Scientists. Retrieved30 October 2013.
    Jump up^ Reif, Kingston. "Pentagon Pushes for Billions to Refurbish Nuclear Bombs". Bulletin of the Atomic Scientists. Retrieved October 25, 2013.
    Jump up^ "Cold War Relic", Air force mag, 4 November 2013.
    Jump up^ Rabechault, Mathieu (6 November 2013). "US to spend billions 'modernizing' nuclear arsenal". Google. AFP. Retrieved 7 November2013.
    Jump up^ Guarino, Douglas P. (16 January 2014). "Nuclear Security and Omnibus Legislation: What's Up and What's Down". Nuclear Threat Initiative. Global Security Newswire. Retrieved 16 January 2014.
    Jump up^ General Confirms Enhanced Targeting Capabilities of B61-12 Nuclear Bomb, Fas, 25 November 2014.
    Jump up^ Keck, Zachary (13 July 2015). "America and Russia Test New Tactical Nuclear Missiles". National interest (The National Interest). Retrieved13 July 2015.
    Jump up^ US conducts first flight test of guided B61-12 nuclear bomb, Flight global, archived from the original on Jul 11, 2015.
    Jump up^ "Glenn's Computer Museum-B61 Preflight Controller". Glennsmuseum.com. Retrieved 2012-07-08.
    Jump up^ "the nuclear information project: the B61-11". Nukestrat.com. Retrieved2012-06-09.
    Jump up^ http://nuclearweaponarchive.org/Usa/Weapons/B61.html
    Jump up^ [1][dead link]
    Jump up^ Grossman, Elaine M. (September 26, 2008). "U.S. Air Force Might Modify Nuclear Bomb". GlobalSecurity.org.
    Jump up^ Nuclear Bomb Update Effort Slowed by Posture Review, Science Studies
    Jump up^ "NNSA Seeks $40M for Nuke Refurbishment Study", Global security news wire, May 18, 2010.
    Jump up^ US tactical nuclear weapons in Europe (PDF), Sage pub, 2011.
    Jump up^ Kristensen, Hans. "B61 LEP: Increasing NATO Nuclear Capability and Precision Low-Yield Strikes." FAS, 15 June 2011.
    Jump up^ Kristensen, Hans. "B61-12: NNSA’s Gold-Plated Nuclear Bomb Project." FAS, 26 July 2012.
    Jump up^ Boeing to Upgrade B61 Nuclear Free Fall Bomb, Deagel, November 27, 2012.
    Jump up^ Boeing Receives $178 Million Contract for B61 Tail Kit Assembly, Media room.
    Jump up^ Kristensen, Hans. "$1 Billion for a Nuclear Bomb Tail." FAS, 12 April 2013.
    Jump up^ Nuclear Bomb Upgrade Could Violate Key Treaty, Defense tech, 28 February 2014.
    Jump up^ US conducts first flight test of guided B61-12 nuclear bomb, Flight global, 10 July 2015.
    External links[edit]
    Wikimedia Commons has media related to B61 nuclear bomb.

    Developing and Producing the B-61 (Google You tube), AEC.
    "B61", Weapons of mass destruction (information), Global Security.
    B61-11 Concerns and Background, Los Alamos Study Group, 1997, an anti-nuclear weapons organization
    Nelson, Robert W (January–February 2001), Low-Yield Earth-Penetrating Nuclear Weapons 54 (1), Federation of American Scientists.
    Norris, Robert S; Kristensen, Hans M; Handler, Joshua (2003), "The B61 family of bombs", Bulletin of the Atomic Scientists.
    B61 Nuclear Bomb Preflight Controller Unit, Glenn’s museum.