A booby trap is a device set up to be triggered by an unsuspecting victim. As the word "trap" implies, they usually have some form of bait designed to lure the victim towards it. In other cases, however, the trap is set to be triggered when the victim performs an everyday action such as opening their door or starting their car. Lethal booby traps are sometimes used in warfare, particularly guerilla warfare, and traps designed to cause injury or pain are also sometimes used by criminals wanting to protect drugs or other illicit property, and by some owners of legal property who wish to protect it from theft. Booby traps which merely cause discomfort or embarrassment are a popular form of practical joke.

History

The term comes from the implication that such a trap will be set off by a foolish person (a "booby"). The first use of the term is from the 1850s, when it was used to describe practical jokes that are set off by their victim. In fact, the term is still used to describe a type of firework which explodes loudly when strings protruding from either end are pulled, which may be tied to a door handle.

Ray Mears suggested that the booby trap name came from the skill of catching boobies - a sea bird, when out at sea. Bait would be placed in the middle of a noose, when the Booby landed on deck to eat the food, the nose would be tightened and catch the bird by the legs.

Military booby traps

A booby trap is distinguished from a land mine by the fact that it is an improvised weapon, often made from some item of ordnance such as an artillery shell, grenade, or quantity of high explosives, whereas a land mine is manufactured for its specific purpose. A booby trap is always concealed or disguised in some way so that it either cannot be seen or looks harmless. Typically, a booby trap will be hidden inside, behind or underneath another object. Part of the skill in placing booby-traps lies in having knowledge of human psychology e.g. exploiting people's natural curiosity or acquisitiveness. A common trick is to provide victims with a simple solution to a problem e.g. leaving only one door open in an otherwise secure building, thereby luring them straight toward the firing mechanism. Attractive or interesting objects are frequently used as bait in order to lure victims into triggering the booby trap. For example, troops could leave behind empty beer bottles and a sealed wooden packing case with "Scotch Whisky" marked on it before leaving an area. The rubble-filled packing case might be resting on top of an M5^[1] or M142 firing device^[2][3], connected to some blocks of TNT ^[4] or to some C4 explosive stuffed into the empty fuze pocket of a mortar shell. Alternatively, the weight of the packing case might simply be holding down the arming lever of an M67 grenade with the safety pin removed. Either way, when the case is moved the booby trap detonates, killing or severely injuring anyone in the immediate area.

Purpose-built booby-trap firing devices (e.g. the M142 universal firing device) exist which allow a variety of different ways of triggering explosives e.g. via trip wire (either pulling it or releasing the tension on it), direct pressure on an object (e.g. standing on it), or pressure release (lift/shift something) etc.

Almost any item can be booby-trapped in some way. For example, boobytrapping flashlights is a classic tactic: a flashlight already contains most of the required components. Firstly, the flashlight acts as bait, tempting the victim to pick it up. More importantly, it is easy to conceal a detonator, some C4 explosive and a PP3 battery inside the flashlight casing. A simple electrical circuit is connected to the on/off button. When the victim switches the flashlight on to check if it works, the resulting explosion blows their arm off and possibly blinds them.

The only real limitations on the intricacy of booby-traps are the skill and inventiveness of the people placing them. For example, the "bait object" (e.g. a cash box in a corner of the room) which lures victims into the trap may not in fact be booby-trapped at all. However, the furniture which must be pushed away in order to get to the bait has a wire attached, with an M142 firing device connected to a 155mm artillery shell on the other end of it.

As a rule, booby-traps are planted in any situation where there is a strong likelihood of them being encountered and triggered. Typically, they are planted in places that people are naturally attracted to or are forced to use. The list of likely placement areas includes:

• the only abandoned houses left standing in a village, which will be a magnet for enemy soldiers seeking shelter
• a door, drawer or cupboard inside a building that someone will open without thinking of what might be connected to it. If a door is locked, this makes people believe there could something valuable behind it so they are more likely to kick it open, with fatal results
• vehicles abandoned by the roadside, perhaps with some kind of victim "bait" left on the back seat
• natural choke-points, such as the only footbridge across a river, which people must use whether they want to or not
• important strategic installations such as airfields, railway stations and harbour facilities, all of which the invading forces will want to occupy and use
• anything of use or value that people would naturally want to possess or which makes them curious to see what is inside it e.g. a crate of beer, a pistol, a flashlight or a discarded army rucksack etc

A booby trap does not necessarily incorporate explosives in its construction. Deadfall traps employing massive or heavy objects set up to fall on and crush the victim who disturbs the triggering mechanism are also a form of booby trap. As is a concealed pit with sharpened stakes in the bottom; often referred to as Punji sticks. However, setting non-explosive booby traps is labour-intensive and time-consuming. Additionally, they are harder to conceal. Although non-explosive booby traps will maim the victim in some way, they rarely kill. In contrast, booby traps containing explosives are much more destructive: they will either kill their victims or severely wound them e.g. blow an arm or leg off.

Effects

In addition to the obvious ability of booby traps to kill or injure, their presence has other effects. These include the ability to:

• demoralize soldiers as a steady stream of booby traps kills or maims comrades
• keep soldiers continually stressed, suspicious and unable to relax because it is difficult for them to know which areas, buildings or objects are safe. They quickly realize that simple, everyday actions like opening doors or picking something up may have fatal consequences
• make soldiers cautious instead of aggressive and confident
• create no-go areas (real or imagined) after a booby trap has killed or wounded someone
• harm civilians and other non-combatants (during and after the conflict) who are unaware that booby traps are present.
• Causing a section or platoon to have to stop in order to deal with casualties, thus slowing and delaying that section or platoon. Used to commence ambushes.

Booby traps are indiscriminate weapons, like anti-personnel mines. Therefore, it is vitally important for the force which places booby traps to keep an accurate record of their location so they can be cleared when the conflict is over.

Usage throughout history

World War II

Retreating British soldiers during the Battle of France in 1940 made booby traps from artillery and mortar shells. These were buried in roads behind them as they retreated, or hung them from trees concealed by the leaves and rigged with tripwires concealed in the grass around the tree.

During the Warsaw Ghetto Uprising, Jewish resistance fighters caused severe Nazi casualties through a vast array of improvised and often elaborate booby traps, set up inside the ghetto buildings and basements. They were so effective that the German forces eventually decided to demolish every building systematically rather than risk entering.

During Germany's retreat from the Soviets in the later years of the war, booby traps were used to slow down the advancing Russian infantry. German infantry would leave poisoned vodka bottles behind, and rig doors with basic trip mines. The same was done on the Western Front in 1944-1945 by retreating German troops. Allied troops often collected desirable weapons such as the Walther P-38 and Luger P-08 pistols for souvenirs, and these items would be left behind, rigged with explosives. If picked up, a hand would be blown off or worse. Another crafty trick involved booby-trapping a hanging picture in a house and tilting it slightly. This was designed to catch Allied officers who would be more likely to note such an imperfection, and more inclined to right it. Other Germans would tie fishing line or piano wire onto trees on opposite sides of a road. When an Allied jeep or motorcycle would come speeding down the road, the "invisible" fishing wire, if put at a proper height, could decapitate or injure troops.

The Germans were in the habit of hiding explosive charges with clockwork time delays (lasting up to a week or more) under the floorboards of buildings in villages and towns that were about to be evacuated. The Germans deliberately chose the most prominent and undamaged buildings, knowing that allied officers would likely occupy them. Though not strictly speaking a booby trap, such time-bombs created stress and suspicion among the occupiers.

Cold War

During the Soviet era in Eastern Europe, the Warsaw Pact countries attempted to better secure their borders with Western Europe by rigging border fences sporadically with explosive devices. These were usually fairly simple devices, often no more complicated than land mines hung on barbed wire. The mines were modified to be sensitive enough to go off if the barbed wire was tampered with or cut.

During the Vietnam War, motorcycles were rigged with explosives by the NLF and abandoned. U.S. soldiers would be tempted to ride the motorcycle and thus trigger the explosives. In addition, NLF soldiers would rig rubber band grenades and place them in huts that US soldiers would likely burn. Another popular booby trap was the "Grenade in a Can", a grenade with the safety pin removed in a container and a string attached, sometimes with the grenade's fuse mechanism modified to give a much shorter delay than the four to seven seconds typical with grenade fuses. The NLF soldiers primarily used these on doors and attached them to tripwires on jungle paths.

The NLF also used simple but effective low-technology punji sticks hidden in pits, often smeared with human feces to increase the risk of infection.

The CIA and Green Berets countered by booby-trapping the enemy's ammunition supplies. The gunpowder in a rifle or machine-gun cartridge was replaced with high explosive. Upon being fired, the sabotaged round would destroy the gun and kill or injure the shooter. Mortar shells were similarly rigged to explode when dropped down the tube, instead of launching properly. This ammunition was then carefully re-packed to eliminate any evidence of tampering, and planted in enemy munitions dumps by covert insertion teams. False rumors and forged documents were circulated to make it appear that the Communist Chinese were supplying the NLF with defective weapons and ammunition.

Northern Irish Troubles

During the Northern Irish Troubles, booby trap bombs were often used by the Irish Republican Army (IRA) to kill off-duty police officers, prison guards and other agents of the British state. A variety of methods were used, the most common being attaching the bomb to a vehicle so that starting or driving it would detonate the explosive. According to the Sutton Index of Deaths, 180 deaths in the Troubles were the result of booby trap bombs, the vast majority of them laid by the IRA.^[5]

Middle East

During the Al-Aqsa Intifada, Palestinian insurgents used booby traps widely. The largest use of booby traps was in Jenin during Operation Defensive Shield where a large number of explosive devices were planted by insurgents. Booby traps had been laid in the streets of both the camp and the town, ready to be triggered if a foot snagged a tripwire or a vehicle rolled over a mine. Some of the bombs were huge, containing as much as 250 lb (110 kg) of explosives.

Gallery

Note: as a general rule all military booby-trap firing devices have a detonator fixed at one end, which is inserted into an explosive charge.

Simple booby trap: concealed pitfall with sharp spike at the bottom

USSR boobytrap firing device - pull fuze: normally connected to a tripwire

Alternative design of USSR boobytrap firing device - pull fuze: normally connected to tripwire

USSR boobytrap firing device - pressure fuze: victim steps on loose floorboard with fuze concealed underneath

Criminal and security use

Booby traps can also be applied as defensive weapons against unwelcome guests or against non-military trespassers, and some people set up traps in their homes to keep people from entering. These civilian booby traps typically use a non-lethal method, such as a strong electric shock, rather than explosives. As laws vary, the creator of the trap can sometimes be immune from prosecution since the victim is technically trespassing or may be held strictly liable for injuries caused to the trespasser. In some jurisdictions some types of traps are specified as illegal if such traps are designed to injure or kill the person triggering the trap. Booby traps may also be used to deter and delay pursuits, and in such context being used by military forces and criminals.

Computer viruses

Main article: Computer virus

Many computer viruses take the form of booby traps in that they are triggered when an unsuspecting user performs an apparently ordinary action such as opening an email attachment.

Practical jokes

Main article: Practical joke device

As well as being used to kill, maim and injure, booby traps can also be used for entertainment. Practical joke booby traps are typically disguised as everyday items such as cigars or packets of chewing gum, nuts or other snack items. When the victims attempts to use the item, the trap is triggered. Two of the best known examples of this are the exploding cigar and dribble glass; others include the Snake Nut Can and shocking gum. Booby traps can also be constructed out of household or workplace items and be triggered when the victim performs a common action. Examples of this include loosening the bolts in a chair so that it collapses when sat on, or placing a bucket of water on top of a partly-open door so that when the door is fully opened, the bucket tips onto the victim.

References

See also

• Anti-handling device
• Combat engineer
• DEMIRA Deutsche Minenräumer
• Improvised explosive device
• Mercury switch
• Microswitch
• Mantrap
• Spring-gun
• Booby prize

External links

• Mines & Boobytrap devices - British guide dated 1943
• How not to get caught by mines and boobytraps - US warning guide dated 1944, and still relevant
• How not to get caught by Vietnamese boobytraps - US guide dated 1969
• Army Field Manual FM531 Boobytraps - US guide dated 1965
• Photos of various booby trap trigger mechanisms
• Photos of booby trap devices used in Angola
• Booby trap concepts and detection techniques
• The Straight Dope: What's the origin of "booby trap"?
• Photos of injuries inflicted by explosive boobytraps (Warning: graphic images)