Electromagnetic bomb

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An electromagnetic bomb or E-bomb is a weapon designed to disable electronics with an electromagnetic pulse (EMP) that can couple with electrical/electronic systems to produce damaging current and voltage surges by electromagnetic induction. The effects are usually not noticeable beyond 10 km of the blast radius unless the device is nuclear or specifically designed to produce an electromagnetic pulse. Small nuclear weapons detonated at high altitudes can produce a strong enough signal to disrupt or damage electronics many miles from the focus of the explosion. During a nuclear EMP, the magnetic flux lines of the Earth alter the dispersion of energy so that it radiates very little to the North, but spreads out East, West, and South of the blast. The signal is divided into several time components, and can result in thousands of volts per meter of electromagnetic energy ranging from extreme negative to extreme positive polarities. This energy can travel long distances on power lines and through the air.

Electromagnetic bombs have been featured in a number of novels, movies, video games and television shows.

Contents 1 Effects 2 History 3 References 4 See also 5 Further reading 6 External links

[edit] Effects

These weapons are not directly responsible for the loss of lives, but can disable some of the electronic systems on which industrialized nations are highly dependent.

Devices that are susceptible to EMP damage, from most to least vulnerable:

1. Integrated circuits (ICs), CPUs, silicon chips.
2. Transistors and diodes.
3. Inductors, electric motors
4. Vacuum tubes: also known as thermionic valves, gold-coated tubes can easily survive and are commonly found in "hardened" electronics like MIG fighter jets' control systems.

Transistor technology is likely to fail and old vacuum equipment survive. However, different types of transistors and ICs show different sensitivity to electromagnetism; bipolar ICs and transistors are much less sensitive than FETs and especially MOSFETs. To protect sensitive electronics, a Faraday cage must be placed around the item. However if the EMP pulse is static or slowly changing it is unstoppable. Some makeshift Faraday cages have been suggested, such as aluminium foil, although such a cage would be rendered useless if any conductors passed through, such as power cords or antennas. A Faraday cage is meant to harmlessly route the signal around the electronics inside, but the conductors on the inside must be insulated from spurious currents that are induced as the signal passes around the surface of the cage. Hardened buildings employ the use of special EM gasketing on doors, special attention to conductive surfaces on the outside, and optical isolators on antennas. The electrical supply to a hardened building must be located at a surprising depth underground in order not to "couple" with the signal, and if the electrical supply is connected to a standard power grid, the EMP will send a large surge (large enough to burn out lightning arrestors) into the power supplies of sensitive electronics.

A comprehensive 2008 report of many of the details of probable EMP effects on the equipment and infrastructure of the United States and other industrialized countries is available in the Critical National Infrastructures Report^[1] written by the scientific members of the United States EMP Commission.

[edit] History

The electromagnetic pulse was first observed during high-altitude nuclear weapon detonations.

Electromagnetic weapons are still mostly classified and research surrounding them is highly secret. Military speculators and experts generally think that E-bombs use explosively pumped flux compression generator technology as their power source, though a relatively small (10 kt) nuclear bomb, exploded between 30 and 300 miles in the atmosphere could send out enough power to damage electronics from coast to coast in the US. The US Army Corps of Engineers issued a publicly available pamphlet in the late 1990s that discusses in detail how to harden a facility against "HEMP" - high frequency electromagnetic pulse. It describes how water pipes, antennas, electrical lines, and windows allow EMP to enter a building.

According to some reports, the U.S. Navy used experimental E-bombs during the 1991 Gulf War. These bombs utilized warheads that converted the energy of conventional explosives into a pulse of radio energy.^[2] CBS News also reported that the U.S. dropped an E-bomb on Iraqi TV during the 2003 invasion of Iraq, but this has not been confirmed.^[3]

The Soviet Union conducted significant research into producing nuclear weapons specially designed for upper atmospheric detonations, a decision that was later followed by the United States and the United Kingdom. Only the Soviets ultimately produced any significant quantity of such warheads, most of which were disarmed following the Reagan-era arms talks.^{[citation needed]} EMP-specialized nuclear weapon designs belong to the third generation of nuclear weapons.

In 2009, Yael Shahar reported that home-build handheld e-bombs prove to be a significant threat to airliners. ^[4]

[edit] References

[edit] See also

• Electronic warfare
• Electromagnetic pulse
• High-energy radio-frequency weapons (HERF)
• High-Altitude Electromagnetic Pulse (HEMP)

[edit] Further reading

• ISBN 978-1592483891 21st Century Complete Guide to Electromagnetic Pulse (EMP) Attack Threats, Report of the Commission to Assess the Threat to the United States from Electromagnetic ... High-Altitude Nuclear Weapon EMP Attacks (CD-ROM)
• ISBN 978-0160561276 Threat posed by electromagnetic pulse (EMP) to U.S. military systems and civil infrastructure: Hearing before the Military Research and Development Subcommittee ... first session, hearing held July 16, 1997 (Unknown Binding)
• ISBN 978-0471014034 Electromagnetic Pulse Radiation and Protective Techniques
• ISBN 978-0-16-080927-9 Report of the Commission to Assess the Threat to the United States from Electromagnetic Pulse (EMP) Attack

[edit] External links

• Popular Mechanics "E-Bombs And Terrorists: September 2001 Cover Story
• Electromagnetic Pulse Risks & Terrorism
• The Electromagnetic Bomb
• E-Bombs and its effects
• How E-Bombs Work