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Improvised explosive device

Unconventionally produced bomb

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Improvised explosive device
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The term "IED" was coined by the British Army during the Northern Ireland conflict to refer to booby traps made by the IRA, and entered common use in the U.S. during the Iraq War.

IEDs are predominantly utilized by violent non-state actors, such as guerrilla or terrorist organizations, who use them in the context of strategies and tactics of insurrection, guerrilla warfare, asymmetric warfare, urban warfare or in terrorist operations. IEDs can also be utilized by state special forces or commando forces, to conduct unconventional warfare in a theatre of operations, such as in the case, for example, of the United States Army Special Forces.

Background

An IED can be defined as a device placed or fabricated in an improvised manner incorporating destructive, lethal, noxious, pyrotechnic or incendiary chemicals and designed to destroy, incapacitate, harass or distract; it may incorporate military stores, but is normally devised from non-military components. IEDs may incorporate military or commercially sourced explosives, and often combine both types, or they may otherwise be made with homemade explosives (HME).

An IED has generally five components: a switch (activator), an initiator (fuse), container (body), charge (explosive), and a power source (battery); an IED designed for use against armoured targets such as personnel carriers or tanks will be designed for armour penetration, by using, for example, a shaped charge that creates an explosively formed penetrator; IEDs are extremely diverse in design and may contain many types of initiators, detonators, penetrators, and explosive loads. Some particularly sophisticated IEDs can also incorporate anti-handling or anti-defusing systems: this was the case, for example, of the IED prepared by John Birges in 1980, used in an extortion attempt against the Harvey's Resort Hotel.

Antipersonnel IEDs typically also contain fragmentation-generating objects such as nails, ball bearings or even small rocks to cause wounds at greater distances than blast pressure alone could. Injuries caused by antipersonnel improvised explosive devices (AP-IED) to dismounted (pedestrian) soldiers and civilians were reported in BMJ Open to be far worse than those caused by conventional antipersonnel mines (APM), resulting in multiple limb amputations and lower body mutilation. This combination of injuries has been given the name "Dismounted Complex Blast Injury" and is thought to be the worst survivable injury ever seen in war.

IEDs are triggered by various methods, including remote control, infrared or magnetic triggers, pressure-sensitive bars or trip wires (victim-operated). In some cases, multiple IEDs are wired together in a daisy chain to attack a convoy of vehicles spread out along a roadway.

IEDs made by inexperienced designers or with substandard materials may fail to detonate, and in some cases, they detonate on either the maker or the placer of the device. Some groups, however, have been known to produce sophisticated devices constructed with components scavenged from conventional munitions and standard consumer electronics components, such as mobile phones, washing machine timers, pagers, or garage door openers. The sophistication of an IED depends on the training of the designer and the tools and materials available.

IEDs may use artillery shells or conventional high-explosive charges as their explosive load as well as homemade explosives. However, the threat exists that toxic chemical, biological, or radioactive (dirty bomb) material may be added to a device, thereby creating other life-threatening effects beyond the shrapnel, concussive blasts and fire normally associated with bombs.

It is possible to categorize IEDs by warhead, by delivery mechanism, by trigger mechanism:

By warhead

The Dictionary of Military and Associated Terms (JCS Pub 1-02) includes two definitions for improvised devices: improvised explosive devices (IED) and improvised nuclear device (IND). These definitions address the Nuclear and Explosive in CBRNe. That leaves chemical, biological and radiological undefined. Four definitions have been created to build on the structure of the JCS definition. Terms have been created to standardize the language of first responders and members of the military and to correlate the operational picture.

General-purpose explosive charges

An IED may be equipped with a general-purpose explosive charge, designed to project a blast wave, with or without additional shrapnel materials, all around itself, for the purpose of inflicting damage to peoples and unarmored targets. Examples of such charges are those contained in IEDs such as pipe bombs, nail bombs, tin can grenades, pressure cooker bombs, car bombs, and so on.

In general, the nature and potential of the explosive substances contained in an IED – both in terms of the main explosive charge and the detonator – is extremely variable: military explosives obtained from modern conventional munitions, such as trinitrotoluene (TNT), Composition B, RDX, pentaerythritol tetranitrate (PETN); commercial or improvised explosives, such as dynamite, ammonium nitrate and fuel oil (ANFO), urea nitrate, chlorate/perchlorate mixtures, nitrate- and peroxide-based mixtures and compounds, triacetone triperoxide (TATP), hexamethylene triperoxide diamine (HMTD).

Directionally focused explosive charges

An IED may be equipped with a directionally focused explosive charge, designed to channel most of the force of the explosion in a single direction. Such IEDs are specifically built to be employed in an anti-personnel or anti-tank/anti-material role.

Examples of anti-personnel IEDs of this category are the fougasse and the grapeshot charge.

A fougasse is an improvised mortar capable of a single discharge, constructed by making a hollow in the ground or rock, placing an explosive charge (originally black powder) at the bottom of it, then covered with various types of projectiles (originally stones); the hollow is camouflaged in the surrounding environment; the fougasse is then fired by means of a fuse or electrically, resulting in the projectiles to be scattered in front of it, along the axis of the excavation of the hollow. An IED with ancient origins, the fougasse was used in warfare – even in a configuration capable of launching incendiary liquids – at least until the Second World War and the Korean War.

A grapeshot charge employs the same general operating principle of the fougasse, but more closely resembling an improvised Claymore mine, also made for directional fragmentation. It is constructed by inserting its major components – projectiles, buffer material, explosive charge and blasting cap – in a portable container, such as a metal tube, an ammo can or a No. 10 can. The trajectory of the multiple projectiles – usually nails, bolts, nuts, ball bearings, glass, small pieces of scrap metal, rocks and other similar shrapnel materials – is flat, as if they were fired from a shotgun.

Examples of anti-tank/anti-material IEDs of this category are the shaped charge, the explosively formed penetrator/projectile (EFP) and the platter charge.

A shaped charge concentrate the energy released by the explosion on a small area, making a tubular or linear fracture in the target; to do so, it present a cavity, usually cone-shaped and lined. The cavity liner can be made from copper, tin, zinc, or glass (funnels or bottles with a cone in the bottom, like champagne or cognac bottles). The high-explosive charge is placed at a very short distance from the target – but still kept at an adequate standoff distance – with the cavity facing the target. When the charge is detonated, the shock wave propagates from the detonator towards the cone-shaped cavity, thus producing a piercing jet of particles at high speed, temperature and pressure, capable of perforating concrete and armor, but which loses effectiveness after a short distance. Historical examples of improvised shaped charges are those devised by the Viet Cong during the Vietnam War, which were incorporated into various types of improvised weapons, such as bounding anti-tank/anti-vehicular mines, demolition charges and anti-tank hand grenades.

An explosively formed penetrator/projectile (EFP) is a special type of shaped charge relying on the Misnay–Schardin effect; also cylindrical, it incorporate a thicker and heavier metal liner, usually a plate made of stamped or machined copper, with a concave lens or dish shape, pointed inward. The plate is aimed at the target. When the high-explosive charge, uniformly packed behind the liner/plate, is detonated, the liner/plate is formed into a projectile called "slug" or "penetrator", which is propelled toward the target at an extremely high velocity. The difference in the shape and weight of the liner allows an EFP to be effective at long standoffs from the target (100 meters or more), thus making it deployable from a greater distance than a traditional shaped charge. The "slug" produced by an EFP is capable of penetrating, from a distance, armoured targets like tanks, however, the accuracy of such devices is limited (approximately 50 meters), due to the way in which EFPs are produced: the "slug" projected from the explosion has no stabilization because it has no tail fins and it does not spin like a bullet from a rifle. This type of IED was used by insurgent forces in recent conflicts, such as the Iraq War (2003–2011), with lethal effects.

A platter charge, is similar to EFPs in construction. The main differences being that the explosive charge does not have a cavity, and that the plate is flat and not concave. Where an EFP made with machined copper to use copper's ductility to create a penetrator, steel plate is used for its strength to resist deformation. The flat face of the explosive charge uniformly launches the projectile. If the projectile deforms into a slug, then it is an EFP. The steel platter stays intact as a plate to use kinetic energy to spall the target if it does not punch through. If it is used in breaching, it can remove most or all of the reinforcing steel as it punches a hole about the size of the platter, whereas an EFP would simply punch a small but deep hole as a penetrator.

Chemical charges

An IED may incorporate toxic attributes of chemical materials designed to result in the dispersal of toxic chemical materials for the purpose of creating a primary patho-physiological toxic effect (morbidity and mortality), or secondary psychological effect (causing fear and behavior modification) on a larger population; such devices may be fabricated in a completely improvised manner or may be an improvised modification to an existing weapon. Substances that could potentially be used as improvised chemical charges include carbamates (Aldicarb), diisopropyl fluorophosphate (DFP) and organophosphates (parathion, methyl and ethyl).

Biological charges

An IED may incorporate biological materials designed to result in the dispersal of vector-borne biological material for the purpose of creating a primary patho-physiological toxic effect (morbidity and mortality), or secondary psychological effect (causing fear and behavior modification) on a larger population; such devices are fabricated in a completely improvised manner. Burkholderia mallei is the bacterium that causes the disease glanders, which could potentially be used as an improvised biological charge.

Incendiary charges

An IED may incorporate incendiary charges, for the purpose of causing and spreading a fire. Examples of such incendiary charges are those constituted by materials and mixtures such as, for example, napalm, thermite, magnesium powder, chlorine trifluoride, white phosphorus, chlorate and sugar, powdered aluminum and sulfur, and so on. Although purely incendiary improvised devices usually do not explode, they are still colloquially referred to as incendiary bombs.

Radiological charges

A speculative IED may incorporate radioactive materials, and being designed to disperse such materials for the purpose of area denial and economic damage, and/or for the purpose of creating a primary patho-physiological toxic effect (morbidity and mortality), or secondary psychological effect (causing fear and behavior modification) on a larger population. Such devices may be fabricated in a completely improvised manner or may be an improvised modification to an existing nuclear weapon. Also called a Radiological Dispersion Device (RDD) or "dirty bomb".

Nuclear charges

A speculative IED, defined as an improvised nuclear device, may incorporate a nuclear charge, most likely a crude atomic bomb of the gun-type.

By delivery mechanism

Car

A vehicle-borne IED (VBIED) is a military term for a car bomb or truck bomb, which can carry a relatively large payload, but can also be any type of transportation, such as a bicycle or a motorcycle. They are typically employed by insurgents, for example by ISIS, which has used truck bombs with devastating effects. They can be detonated by remote control or by a passenger/driver. The act of a person's being in this vehicle and detonating it is known as an SVBIED suicide. On occasion the driver of the car bomb may have been coerced into delivery of the vehicle under duress, a situation known as a proxy bomb. Distinguishing features are low-riding vehicles with excessive weight, vehicles with only one passenger, and ones where the interior of the vehicles look as if they have been stripped down and built back up. Car bombs can carry thousands of pounds of explosives and may create additional shrapnel damage through the destruction of the vehicle itself and by the use of the vehicle fuel as an incendiary weapon.

Boat

A water-borne improvised explosive device (WBIED) is a surface or subsurface improvised explosive device that is anchored, floating, or propelled – for example, a small boat. An early example of this type was the Japanese Shinyo suicide boats during World War II. The boats were filled with explosives and attempted to ram Allied ships, sometimes successfully, having sunk or severely damaged several American ships by war's end. Suicide bombers used a boat-borne IED to attack the USS Cole; US and UK troops have also been killed by boat-borne IEDs in Iraq. The Liberation Tigers of Tamil Eelam (LTTE) have been known to use WBIEDs during the Sri Lankan Civil War. WBIEDs have also been used in the Red Sea.

Animal

Monkeys and war pigs were used as incendiaries around 1000 AD. More famously the "anti-tank dog" and "bat bomb" were developed during World War II. In recent times, a two-year-old child and seven other people were killed by explosives strapped to a horse in the town of Chita in Colombia. In Afghanistan, local insurgents have used animals to transport IEDs. The carcasses of certain animals were also used to conceal explosive devices by the Iraqi insurgency.

Collar

IEDs strapped to the necks of farmers have been used on at least three occasions by guerrillas in Colombia, as a way of extortion. American pizza delivery man Brian Douglas Wells was killed in 2003 by an explosive fastened to his neck, purportedly under duress from the maker of the bomb. In 2011 a woman in Sydney, Australia had a suspected collar bomb attached to her by an attacker in her home. The device was removed by police after a ten-hour operation and proved to be a hoax.

Suicide

Suicide bombing usually refers to an individual wearing explosives and detonating them to kill others including themselves, the bomber will conceal explosives on and around their person, commonly using a vest, and will use a timer or some other trigger to detonate the explosives. The logic behind such attacks is the belief that an IED delivered by a human has a greater chance of achieving success than any other method of attack. In addition, there is the psychological impact of child soldiers prepared to deliberately sacrifice themselves for their cause.

Surgically implanted

In May 2012 American counter-terrorism officials leaked their acquisition of documents describing the preparation and use of surgically implanted improvised explosive devices. Security officials referred to bombs being surgically implanted into suicide bombers' "love handles". According to the Daily Mirror UK security officials at MI-6 asserted that female bombers could travel undetected carrying the explosive chemicals in otherwise standard breast implants. The bomber would blow up the implanted explosives by injecting a chemical trigger.

Robot/drone

Robots could also be used to carry explosives. The first such documented case was during the aftermath of 2016 shooting of Dallas police officers when a bomb disposal robot was used to deliver explosives to kill Micah Xavier Johnson, who was hiding in a place inaccessible to police snipers. As well, drones carrying explosives were used in a suspected assassination attempt against Venezuelan president Nicolás Maduro in 2018. Drug cartels in Mexico have shown the ability to produce drone-borne IEDs.

Tunnel

ISIS and Al-Nusra have used bombs detonated in tunnels dug under targets.

House

Among insurgent forces in Iraq was popular the house-borne IED, or HBIED, from the common military practice of clearing houses: insurgents used to rig an entire house to detonate and collapse it shortly after an enemy clearing squad had entered it.

Improvised rocket

In 2008, rocket-propelled IEDs, dubbed "Improvised Rocket Assisted Munitions" (IRAMs) by the military, came to be employed in numbers against U.S. forces in Iraq. They have been described as propane tanks packed with explosives and powered by 107 mm rockets. New types of IRAMs, including "Volcano IRAMs" and "Elephant Rockets", were used during the Syrian Civil War.

Improvised mortar

Improvised mortars have been used by many insurgent groups, including during the civil war in Syria and the Boko Haram insurgency. During The Troubles, the IRA used various models of improvised mortars, some of which were nicknamed "barrack busters". Improvised artillery pieces nicknamed "hell cannons" were used by rebel forces during the Syrian Civil War.

By trigger mechanism

Fuse

An IED can be initiated by a length of fuse (such as a safety fuse or a visco fuse), which can be attached to a non-electric detonator.

Wire

Command-wire improvised explosive devices (CWIED) use an electrical firing cable, that affords the user complete control over the device right up until the moment of initiation.

Radio

The trigger for a radio-controlled improvised explosive device (RCIED) is controlled by radio link. The device is constructed so that the receiver is connected to an electrical firing circuit and the transmitter operated by the perpetrator at a distance. A signal from the transmitter causes the receiver to trigger a firing pulse that operates the switch. Usually the switch fires an initiator; however, the output may also be used to remotely arm an explosive circuit. Often the transmitter and receiver operate on a matched coding system that prevents the RCIED from being initiated by spurious radio frequency signals or jamming. An RCIED can be triggered from any number of different radio-frequency based mechanisms including handheld remote control transmitters, car alarms, wireless door bells, cell phones, pagers and portable two-way radios, including those designed for the CB radio service, UHF PMR446, FRS, and GMRS services.

Mobile phone

A radio-controlled IED (RCIED) incorporating a mobile phone that is modified and connected to an electrical firing circuit. Mobile phones operate in the UHF band in line of sight with base transceiver station (BTS) antennae sites. In the common scenario, receipt of a paging signal by phone is sufficient to initiate the IED firing circuit.

Victim-operated

Victim-operated improvised explosive devices (VOIED), also known as booby traps, are designed to function upon contact with a victim. VOIED switches are often well hidden from the victim or disguised as innocuous everyday objects. They are operated by means of movement. Switching methods include tripwire, pressure mats, spring-loaded release, push, pull or tilt. Common forms of VOIED include the under-vehicle IED (UVIED), improvised landmines, and mail bombs.

Infrared

The British accused Iran and Hezbollah of teaching Iraqi fighters to use infrared light beams to trigger IEDs. As the occupation forces became more sophisticated in interrupting radio signals around their convoys, the insurgents adapted their triggering methods. In some cases, when a more advanced method was disrupted, the insurgents regressed to using uninterruptible means, such as hard wires from the IED to detonator; however, this method is much harder to effectively conceal. It later emerged however, that these "advanced" IEDs were actually old IRA technology. The infrared beam method was perfected by the IRA in the early 1990s after it acquired the technology from a botched undercover British Army operation. Many of the IEDs being used against the invading coalition forces in Iraq were originally developed by the British Army who unintentionally passed the information on to the IRA. The IRA taught their techniques to the Palestine Liberation Organization and the knowledge spread to Iraq.

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