Nuclear bunker buster
A nuclear bunker buster,.
Base principle
While conventional bunker busters use several methods to penetrate concrete structures, these are for the purpose of destroying the structure directly, and are generally limited in how much of a bunker (or system of bunkers) they can destroy by depth and their relatively low explosive force (compared to nuclear weapons).
The primary difference between conventional and nuclear bunker busters is that, while the conventional version is meant for one target, the nuclear version can destroy an entire underground bunker system.
The main principles in modern bunker design are largely centered around survivability in nuclear war. As a result of this both American and Soviet sites reached a state of "super hardening", involving defenses against the effects of a nuclear weapon such as spring- or counterweight-mounted (in the case of the R-36) control capsules and thick concrete walls (3 to 4 feet (0.91 to 1.22 m) for the Minuteman ICBM launch control capsule) heavily reinforced with rebar. These systems were designed to survive a near miss of 20 megatons.[citation needed]
Liquid-fueled missiles such as those historically used by Russia are more fragile and easily damaged than solid-fueled missiles such as those used by the United States. The complex fuel storage facilities and equipment needed to fuel missiles for launch and de-fuel them for frequent maintenance add additional weaknesses and vulnerabilities. Therefore, a similar degree of silo "hardening" does not automatically equate to a similar level of missile "survivability".[citation needed]
Major advancements in the accuracy and precision of nuclear and conventional weapons subsequent to the invention of the missile silo itself have also rendered many "hardening" technologies useless. With modern weapons capable of striking within feet (meters) of their intended targets, a modern "near miss" can be much more effective than a "hit" decades ago. A weapon need only cover the silo door with sufficient debris to prevent its immediate opening to render the missile inside useless for its intended mission of rapid strike or counter-strike deployment.[citation needed]
A nuclear bunker buster negates most of the countermeasures involved in the protection of underground bunkers by penetrating the defenses prior to detonating. A relatively low yield may be able to produce seismic forces beyond those of an air burst or even ground burst of a weapon with twice its yield.[citation needed] Additionally, the weapon has the ability to impart more severe horizontal shock waves than many bunker systems are designed to combat by detonating at or near the bunker's depth, rather than above it.
Geologic factors also play a major role in weapon effectiveness and facility survivability. Locating facilities in hard rock may appear to reduce the effectiveness of bunker-buster type weapons by decreasing penetration, but the hard rock also transmits shock forces to a far higher degree than softer soil types. The difficulties of drilling into and constructing facilities within hard rock also increase construction time and expense, as well as making it more likely construction will be discovered and new sites targeted by foreign militaries.[citation needed]
Methods of operation
Penetration by explosive force
Concrete structure design has not changed significantly in the last 70 years.[citation needed] The majority of protected concrete structures in the U.S. military are derived from standards set forth in Fundamentals of Protective Design, published in 1946 (US Army Corps of Engineers). Various augmentations, such as glass, fibers, and rebar, have made concrete less vulnerable, but far from impenetrable.
When explosive force is applied to concrete, three major fracture regions are usually formed: the initial crater, a crushed aggregate surrounding the crater, and "scabbing" on the surface opposite the crater. Scabbing, also known as spalling, is the violent separation of a mass of material from the opposite face of a plate or slab subjected to an impact or impulsive loading, without necessarily requiring that the barrier itself be penetrated.
While soil is a less dense material, it also does not transmit shock waves as well as concrete. So while a penetrator may actually travel further through soil, its effect may be lessened due to its inability to transmit shock to the target.
Hardened penetrator
Further thinking on the subject envisions a hardened penetrator using kinetic energy to defeat the target's defenses and subsequently deliver a nuclear explosive to the buried target.
The primary difficulty facing the designers of such a penetrator is the tremendous heat applied to the penetrator unit when striking the shielding (surface) at hundreds of meters per second. This has partially been solved by using metals such as tungsten (the metal with the highest melting point), and altering the shape of the projectile (such as an ogive).
Altering the shape of the projectile to incorporate an ogive shape has yielded substantial improvement in penetration ability. Rocket sled testing at Eglin Air Force Base has demonstrated penetrations of 100 to 150 feet (30 to 46 m) in concrete [citation needed] when traveling at 4,000 ft/s (1,200 m/s). The reason for this is liquefaction of the concrete in the target, which tends to flow over the projectile. Variation in the speed of the penetrator can either cause it to be vaporized on impact (in the case of traveling too fast), or to not penetrate far enough (in the case of traveling too slowly). An approximation for the penetration depth is obtained with an impact depth formula derived by Sir Isaac Newton.
Combination penetrator-explosive munitions
Another school of thought on nuclear bunker busters is using a light penetrator to travel 15 to 30 meters through shielding, and detonate a nuclear charge there. Such an explosion would generate powerful shock waves, which would be transmitted very effectively through the solid material comprising the shielding (see "scabbing" above).
Policy and criticism of fallout
The main criticisms of nuclear bunker busters regard fallout and nuclear proliferation. The purpose of an earth-penetrating nuclear bunker buster is to reduce the required yield needed to ensure the destruction of the target by coupling the explosion to the ground, yielding a shock wave similar to an earthquake. For example, the United States retired the
Critics also worry that the existence of lower-yield nuclear weapons for relatively limited tactical purposes will lower the threshold for their actual use, thus blurring the sharp line between conventional weapons intended for use and weapons of mass destruction intended only for hypothetical deterrence, and increasing the risk of escalation to higher-yield nuclear weapons.[3]
Local fallout from any nuclear detonation is increased with proximity to the ground. While a megaton-class yield
The
Critics further state that the testing of new nuclear weapons would be prohibited by the proposed
Proponents, however, contend that lower explosive yield devices and subsurface bursts would produce little to no climatic effects in the event of a nuclear war, in contrast to multi-megaton air and surface bursts (that is, if the nuclear winter hypothesis proves accurate). Lower fuzing heights, which would result from partially buried warheads, would limit or completely obstruct the range of the burning thermal rays of a nuclear detonation, therefore limiting the target, and its surroundings, to a fire hazard by reducing the range of thermal radiation with fuzing for subsurface bursts.[5][6] Professors Altfeld and Cimbala have suggested that belief in the possibility of nuclear winter has actually made nuclear war more likely, contrary to the views of Carl Sagan and others, because it has inspired the development of more accurate, and lower explosive yield, nuclear weapons.[7]
Targets and the development of bunker busters
As early as 1944, the Barnes Wallis
Development continued, with weapons such as the nuclear B61, and conventional thermobaric weapons and GBU-28. One of the more effective housings, the GBU-28 used its large mass (2,130 kg or 4,700 lb) and casing (constructed from barrels of surplus 203 mm howitzers) to penetrate 6 meters (20 feet) of concrete, and more than 30 metres (98 feet) of earth.[11] The B61 Mod 11, which first entered military service after the Cold war had ended, in January 1997, was specifically developed to allow for bunker penetration, and is speculated to have the ability to destroy hardened targets a few hundred feet beneath the earth.[12]
While penetrations of 20–100 feet (6.1–30.5 m) were sufficient for some shallow targets, both the Soviet Union and the United States were creating bunkers buried under huge volumes of soil or reinforced concrete in order to withstand the multi-megaton thermonuclear weapons developed in the 1950s and 1960s. Bunker penetration weapons were initially designed within this Cold War context. One likely Soviet Union/Russian target, Mount Yamantau, was regarded in the 1990s by Maryland Republican congressman, Roscoe Bartlett, as capable of surviving "half a dozen" repeated nuclear strikes of an unspecified yield, one after the other in a "direct hole".[13][14]
The Russian
The weapon was revisited[
The Bush administration removed its request for funding[19] of the weapon in October 2005. Additionally, then U.S. Senator Pete Domenici announced funding for the nuclear bunker-buster has been dropped from the U.S. Department of Energy's 2006 budget at the department's request.[20]
While the project for the RNEP seems to be in fact canceled,
A more recent development (c. 2012) is the
Notable US nuclear bunker busters
Note that with the exception of strictly earth penetrating weapons, others were designed with air burst capability and some were depth charges as well.
- Mark 8 nuclear bomb (1952-1957): earth penetrating
- W8 for SSM-N-8 Regulus (cancelled): earth penetrating
- Mark 11 nuclear bomb (1956-1960): earth penetrating
- Mk 105 Hotpoint (1958-1965): laydown delivery
- B28 nuclear bomb (1958-1991): laydown delivery and ground burst
- Mark 39 nuclear bomb (1958-1962) laydown delivery and ground burst
- B43 nuclear bomb (1961-1990): laydown delivery and ground burst
- B53 nuclear bomb (1962-1997): laydown delivery
- B57 nuclear bomb (1963-1993): laydown delivery
- B61 nuclear bomb (1968-present): laydown delivery and ground burst
- Mod 11 (1997-present): earth penetrating, laydown delivery, and ground burst
- W61 for MGM-134 Midgetman (cancelled): earth penetrating
- B77 nuclear bomb (cancelled): laydown delivery
- B83 nuclear bomb (1983-present): laydown delivery and ground burst
- W86 for Pershing II (cancelled): earth penetrating
- Robust Nuclear Earth Penetrator (cancelled): earth penetrating
See also
- Bunker buster (conventional, non-nuclear)
- Earthquake bomb
- Underground nuclear weapons testing
- Nuclear strategy
- Thermobaric weapon
- Nuclear weapon
- List of nuclear weapons
Citations
- ^ The B61-based “Robust Nuclear Earth Penetrator:” Clever retrofit or headway towards fourth-generation nuclear weapons?
- ^ "Low-Yield Earth-Penetrating Nuclear Weapons By Robert W. Nelson".
- ^ Harald Müller, Stephanie Sonius (2006), Intervention und Kernwaffen – Zur neuen Nukleardoktrin der USA (in German), DE, archived from the original on 19 July 2011, retrieved 15 February 2008
{{citation}}
: CS1 maint: location missing publisher (link) - ^ Comprehensive Nuclear Test Ban Treaty (CTBT) (PDF), MIIS, 10 May 2012, archived (PDF) from the original on 25 October 2011
- ^ "A Nuclear Winter's Tale - the MIT Press". Archived from the original on 6 April 2012. Retrieved 12 May 2014. A Nuclear Winter's Tale: Science and Politics in the 1980s, Lawrence Badash, p.235
- ^ The Medical implications of nuclear war by Fredric Solomon, Robert Q. Marston, Institute of Medicine (U.S.), National Academies, 1986, p. 106
- ^ "A Nuclear Winter's Tale - the MIT Press". Archived from the original on 6 April 2012. Retrieved 12 May 2014. A Nuclear Winter's Tale: Science and Politics in the 1980s, Lawrence Badash, p.242
- ^ RAF Bomber Command Grand Slam raids, United Kingdom: Ministry of Defence, archived from the original on 26 February 2014.
- ^ "July 1944", RAF Bomber Command Campaign Diary July 1944, UK: Ministry of Defence, (6 July "Mimoyecques V-Weapon Site" photograph shows clearly the camouflet effect), archived from the original on 14 May 2005
- ^ "Saumur", RAF Bomber Command Saumur Tunnel Raid, UK: Ministry of Defence, archived from the original on 26 February 2014.
- ^ "GBU-28", The Conduct of the Persian Gulf War (report to Congress), Rice, archived from the original on 2 February 2007, retrieved 14 January 2006.
- ^ "The B61 (Mk-61) Bomb", USA weapons, Nuclear weapon archive, archived from the original on 27 February 2009.
- ^ "Yamantau Whats going on in the Yamantau mountain complex?".
- ^ "Secret Bases Russia Yamantau Mountain Complex Beloretsk, Russia".
- ^ "WINDOW ON HEARTLAND Geopolitical notes on Eastern Europe, the Caucasus and Central Asia". Archived from the original on 24 April 2013.
- Washington Times, 1 April 1997
- ^ "Global Security.org Kosvinsky Mountain, Kos'vinskiy Kamen', Gora, MT 59°31'00"N 59°04'00"E".
- ^ "RNEP". 21 September 2006.
- ^ "US cancels bunker bomb programme", BBC, 26 October 2005, archived from the original on 24 April 2014
- ^ Hebert, H. Josef (25 October 2005), "Bush Admin. Drops 'Bunker-Buster' Plan", Yahoo! News, Associated Press, archived from the original on 27 October 2005, retrieved 6 March 2014
- ^ US dumps bunker-buster – or not?, Jane's, archived from the original on 22 October 2007.
References
- Clifton, James R, Penetration Resistance of Concrete: A Review, The Physical Security and Stockpile Directorate, Defense Nuclear Agency.
- Ernest, Jonathan V; et al. (2005), Nuclear Weapon Initiatives: Low-yield R&D, Advanced Concepts, Earth Penetrators, Test Readiness, Nova Publishers, ISBN 1-59454-203-1.
- Moore, RT, Barrier Penetration Tests, National Bureau of Standards.
- Woolf, Amy F (2005), U.S. Nuclear Weapons: Changes In Policy And Force Structure, Nova Science Publishers, Incorporated, ISBN 1-59454-234-1.
External links
- Allbombs.html list of all US nuclear warheads at nuclearweaponarchive.org
- Gronlund, Lisbeth; Wright, David; Nelson, Robert (May 2005), Earth Penetrating Weapons, US: Union of Concerned Scientists.
- Effects of Nuclear Earth-Penetrator and Other Weapons, The National Academies Press, 2005, ISBN 978-0-309-09673-7.
- Hambling, David (7 November 2002), "Bunker-busters set to go nuclear", New Scientist.
- Nelson, Robert W (January–February 2001), "Low-Yield Earth-Penetrating Nuclear Weapons", Federation of American Scientists, 54 (1)/
- Gsponer, Andre (31 March 2007), The B61-based "Robust Nuclear Earth Penetrator:" Clever retrofit or headway towards fourth-generation nuclear weapons?, Independent Scientific Research Institute, Bibcode:2005physics..10052G.