Military

COMBAT CLEARANCE

Engineers are primarily responsible for clearing booby traps and nuisance mines in AOs. Therefore, engineer advice is important during the planning stages of any operation where booby traps are likely to be encountered. Intelligence regarding the possible presence and types of traps must be provided to engineer units as soon as possible. This allows the unit to take necessary action and provide relevant training. Clearance of booby traps cannot be undertaken as a secondary task, because engineer clearing teams might require protection that necessitates combined arms training. Before engineer planning can start, the staff provides commanders with the latest intelligence information and, if possible, the following information:

  • Amount of clearance required.
  • Acceptable damage.
  • Time requirements.
  • Availability of special equipment.
  • Security requirements.

Intelligence information regarding the nature, type, and location of traps has a direct bearing on the number of clearing parties necessary and the degree of protection required. For example, in built-up areas where traps have to be cleared in buildings that offer protection from enemy fire, direct protection is usually provided by the normal combat situation. On the other hand, in open areas where clearing parties may be required to clear traps covered by direct enemy fire, protection arrangements must be more specific.

Engineer commanders must be aware of the time needed to clear various types of traps in differing terrain situations. Remember, increasing the number of clearance parties may not necessarily reduce the time required to clear traps. This is particularly true when traps are set close together or set deep along a narrow front that is the only available route.

Initially, clear areas of immediate tactical importance and traps that present a specific threat. For example, clear only the portion of a building required for observation and those traps presenting an immediate hazard. This enables clearing parties to concentrate on other areas of tactical importance.

Clearing traps by hand is the only way that damage can be avoided and security guaranteed. This should only be attempted by the EOD when it is vital to maintain silence (and thus conceal the operation from the enemy) or to avoid equipment or structure damage. It is often necessary to balance the requirement to remain silent and avoid damage with the requirement to maintain momentum.

When traps are being cleared in direct-support combat situations, they are normally dealt with by using unit resources and locally manufactured or acquired aids. Specified equipment is rarely available. Equipment varies with the situation but usually consists of selected items from Table 13-2. In areas with a high incidence of booby traps, assemble and reserve special clearing kits.

Table 13-2. Clearing equipment

Item Remarks
Unit Equipment
Mine detector  
Mine probe/knife/bayonet  
Eye protection  
Body armor Flak jacket, Kevlar helmet
Booby-trap signs  
Mine marking tape  
Mine markers Chalk, felt-tipped pens
Electrician's adhesive tape  
Flashlight  
Tape measure  
Mine marking cones  
Trademan's tools Saws, pliers, hammers, screwdrivers
Self-developing camera and film  
Locally Manufactured/Acquired
Trip-wire feeler  
Grapnel and rope  
Hand mirrors  
Pins, wire, nails For use as safety pins
Meat hooks For use as block and tackle

CLEARANCE IN SECURE AREAS

POLICY AND PLANNING

Formal clearing procedures must be followed in secure areas. This type of clearance can be done by engineers or EOD personnel. It is subject to time constraints when traps or suspected traps are located in urgently required installations or facilities, such as supply dumps or telecommunication centers.

Commanders reconnoiter their areas of responsibility, make detailed plans, prepare orders, and brief their men. The following points are covered:

  • Intelligence.
  • How the operation is to be conducted (include acceptable damage and methods of clearing).
  • Action on finding traps.
  • Marking.
  • Disarming procedures.
  • Tasking and allocation of areas.
  • Equipment available.
  • Control measures.
  • Time requirements.
  • Rehearsal and equipment preparation.

CONTROL POINT

The operation commander establishes a control point upon arrival at the area to be cleared. The control point functions as the headquarters and the material holding area. It is also the point from which all clearance starts. Its suitability might not have escaped the enemy's notice, so it must be cleared before it can be used.

CONTROL AND SIZE OF PARTIES

The size of clearing parties varies depending on the location being cleared. The following rules apply:

  • Each party is controlled by an NCO.
  • Only one party works in a particular subarea.
  • The distance between parties is sufficient so that detonation in one area does not endanger persons in other areas.
  • The NCOIC of each party is in visual, radio, or voice contact with every person in his party.
  • Only one person works on a booby trap.

MARKING

Booby traps and nuisance mines can be placed in diverse locations. It is impossible to standardize a method for marking areas, individual traps, or safe routes. Any form of prominent, permanent marking can be used.

Uncleared Areas

The perimeter marking of uncleared areas can take any clearly recognized form. Standard minefield or booby-trap signs suspended from a single-strand fence are recommended. The spacing of the signs is the same as standard minefield marking (see Chapter 2). As the area is cleared, the fence should be progressively moved.

Individual Traps

Because booby traps can have more than one means of actuation, do not attempt to place a cone or other marker over any part of a trap. Use sufficient signs to ensure that the trap can be detected and accurately located. In buildings, clearly mark rooms containing traps and, where possible, indicate the exact location of traps.

Internal Marking

The internal marking system depends on the area being cleared. One good system is to divide the total area into subareas, clear and mark safe lanes between the subareas, and then use the lanes as safe routes.

CLEARING OF OPEN AREAS

Roads, road shoulders, bridges, obstacles, and other structures must be cleared in open areas. The main threat comes from nuisance mines, so regard each potential site as a nuisance minefield and use established minefield clearing procedures. After the site is cleared, adapt the drill to suit the situation.

CLEARING OF BUILDINGS

Buildings are excellent locations for booby traps. Booby traps are concentrated inside the building, so carefully organize search and clearing procedures. In most cases, buildings are required for use, and excessive damage must be avoided.

A two-man clearing party can clear an average-size structure. No one else should enter the building until it is cleared. In very large buildings, two or more parties can be employed, if they work as far apart as possible and have clearly defined boundaries. As a general rule, two walls or two floors is the minimum distance between parties.

EXTERIOR RECONNAISSANCE AND ENTRY

Before approaching a building, check the surrounding area for booby traps and nuisance mines. Carry out a reconnaissance to determine the point of entry and clear the way to it. When selecting the point of entry, consider the following:

  • Doorways. Never consider doorways to be safe unless the door is fully open and the entrance is clear. If a house is built on a concrete slab, it is not likely to have a pressure FD in the floor.
  • Windows. Windows are excellent locations for booby traps. Pay particular attention to the ground outside and the floor inside because they are classic sites for pressure FDs. Use the following procedures if access must be gained through a window:

  • Pull the window if it is unlocked and can be moved. If it is locked, use a small charge or a heavy object to break the glass.
    Select a stationary window that cannot be opened versus a window that can be opened when both types are available, because the window that can be opened is more likely to contain a booby trap.
    Deal with blinds and curtains in a manner similar to procedures used for windows.
    Use a mirror to examine inside the window frame before entering the building.
  • Mouseholes. If you decide not to enter the structure through a door or a window, use explosives to make a mousehole in the wall, roof, or floor. This offers a remote, safe method of creating an access point, but it can also detonate nearby traps. Exercise caution if entering through the roof of a two-story building, because it is far more difficult to clear booby traps when going down steps than it is when going up them.

SEARCH TECHNIQUES

It is impossible to establish a search drill that is suitable for use in all buildings. It is essential, however, for each working party to develop its own drill and follow it. Domestic dwellings should be searched in the following order:

1. Floors and furniture.

2. Walls (including doors, windows, fireplaces, and cupboards).

3. Fittings (including light switches and pictures).

4. Ceilings.

Mark each area or item SAFE as it is cleared. This can be conveniently done by using chalk or a felt-tipped pen.

Use the following techniques and precautions when searching buildings. They can save your life--learn and remember them!

  • Check both sides of a door before opening it. Do this by drilling a hole through the door and using a mirror to check the other side. You can also check or open doors by pulling or blowing the lock and hinges with a small charge.
  • Examine floor coverings for signs of disturbance. The presence of FDs is often indicated by loose floorboards, bulges or tears in carpets, or loose tiles.
  • Use a pulling cable to move furniture and to open cupboard doors and drawers.
  • Check upholstered furniture and beds by remotely dropping a heavy object onto them.
  • Treat every switch with suspicion, since electrical wiring provides a ready-made circuit for booby traps. To explode all the traps connected to the normal power supply, disconnect the power at the fuse board, turn all the switches on, and then reconnect the power. Repeat the procedure with the switch turned off in case the switch has been reversed. Remember, this procedure will not disclose traps that use a battery. Exercise caution when using switches, even if the power is disconnected.
  • Leave doors, windows, cupboards, and drawers open after they have been cleared.
  • Mark all routes, areas, and items that have been cleared.
  • Check plumbing by remotely turning on all water taps and allowing the water to run for at least one minute.
  • Check toilet tanks before flushing.
  • Beware of light-sensitive devices in dark places (closets, cabinets, basements, attics, chimneys).
  • Allow at least 30 seconds for an explosion after pulling anything, because there might be a delay fuse.

CLEARING INSTALLATIONS AND FACILITIES

Clearing by hand is necessary in installations and facilities (fuel dumps, ammunition dumps, electric substations) where an explosion could result in the loss of resources. In other situations, the item's importance or the resulting damage might not be obvious. For example, a small charge placed against the control valves of a dam or against the main cable entering a telephone exchange results in unforeseen damage that can take days to repair. Therefore, you should seek a specialist's advice, if possible, when clearing booby traps in industrial areas and unfamiliar locations.

CLEARING OBSTACLES

If an enemy has time to create obstacles, he also has time to set booby traps and lay nuisance mines. The obstacle itself is usually clear of traps to encourage a false sense of security and lead troops into more dangerous areas. Therefore, regard all obstacles as booby-trapped until proven otherwise. The simplest, safest way to deal with movable obstacles is to pull them. Before an obstacle can be pulled, you must first clear the area from which the pull will be made.

CLEARING SECURE AREAS

When clearing secure areas and time is not a major factor, use specialized clearance equipment as much as possible. The following equipment might be available for use:

  • Cameras. Cameras have a wide range of applications. They can be used with different types of film, such as infrared and ultraviolet, to disclose evidence that is indiscernible to the naked eye. For example, infrared photography reveals differences in the heat emitted by objects and can often disclose recent digging and buried or concealed objects.
  • Explosive detector dogs (EDDs). Although EDDs can detect minute quantities of explosives and the presence of trip wires, they are trained to detect the charge and not the FD. This extremely limits their usefulness in detecting booby traps. They also tend to become confused if the area contains explosive odors other than those emitting from booby traps.
  • Electronic countermeasures. Electronic countermeasures can be used to explode electric booby traps and to prevent remotely controlled, improvised explosive devices from being detonated by radio.
  • Robots. In their simplest form, robots can be used to detonate or neutralize booby traps. More sophisticated models can be remotely controlled to carry out simple tasks, such as videotaping or cutting wires.
  • Body armor.
  • Electric meters.
  • X-ray equipment.

CLEARANCE METHODS

  • Pulling. This method uses a grapnel and a rope to pull the trap. It is used when the resulting damage is acceptable. It is the safest method and is particularly applicable to traps set in open areas. Do not disturb any part of a booby trap when placing the grapnel and pulling the cable. Carefully select the site from where the pull is to be made because it might be mined or trapped. When a booby trap is pulled and does not explode, wait at least 30 seconds before approaching it in case delay devices have been used. Disposal of unexploded traps depends on their condition when inspected. The procedure for pulling booby traps is similar to that for pulling mines (see Chapter 11).
  • Trip wires. Check the area for AP devices before proceeding. Place a grapnel hook as close as possible to the trip wire. Do not touch the trip wire until the pulling party is in a covered area.
  • Pull and release. Pull away objects that conceal and operate pull and release mechanisms.
  • Pressure mechanism. Pull pressure mechanisms from under objects that conceal and operate them. If this is impossible, blow them in place. In many cases, it might be easier to pull the charge rather than the FD. Take extreme care when attempting this, because additional mechanisms are often concealed in or under the main charge.
  • Destructing in place. When destructing booby traps in place, explode a small charge near the booby trap's charge. Again, use this method only if damage from the explosion is acceptable. When it is impossible to place the explosive close enough to ensure actuation of the main charge, carefully place it alongside the mechanism. Do not assume the main charge is safe to handle just because the mechanism has been destroyed. Actuate pressure mechanisms by suspending one-half pound of explosive above the pressure plate.
  • Clearing by hand. This method involves neutralizing, disarming, removing, and disposing of traps without causing damage. It is extremely hazardous and should only be used when pulling or destructing traps in place is impossible or unacceptable. Clearance should only be conducted by EOD personnel or experienced engineers. Carefully examine all aspects of the trap before deciding how to clear it.
  • Explosive line charge. Using this device produces quick results when only a narrow path is required through a booby-trapped area. It gives clearance for the same distance to either side, only where it is in contact with the ground.
  • Armor. This method is used where traps with small charges (designed as AP devices) are located in open areas. Armored vehicles track back and forth over the area. This shortens the clearing time with little risk of casualties.
  • Fire. If traps are set in grass or dense vegetation, fire can be used to burn away camouflage material and expose traps. In most cases, sufficient heat is generated to burn or explode the traps. Unexploded traps are considered extremely sensitive and must not be cleared by hand.

IMPROVISED TRAPS

In low-intensity conflicts, there is a high incidence of improvised mines and booby traps. It is impossible to provide a complete list of FDs and improvised demolition material that can be used. However, most improvised traps are variations of those described below.

An electric FD requires a current to be passed between two contacts. The ways in which this can be achieved are limited only by the imagination. Examples of simple electric FDs that can be manufactured using household items or appliances are shown in Figure 13-6. Examples of improvised mechanical FDs are shown in Figures 13-7 and 13-8.

Figure 13-6. Improvised electrical FDs

Figure 13-7. Improvised nonelectrical FDs (shear-pin operated)

Figure 13-8. Improvised nonelectrical FDs (spring-operated)

The simplest and most accurate method of incorporating delay is to use some form of clock or timer. However, any mechanism or chemical reaction that takes a measurable time to complete its function can be used. Examples of simple improvised delay devices are shown in Figures 13-9 and 13-10.

Figure 13-9. Improvised, electric delay devices

Figure 13-10. Improvised, nonelectric delay devices

NONEXPLOSIVE TRAPS

Nonexplosive traps are typically used in tropical or rain-forest regions. Ideal construction materials abound, and concealment in surrounding vegetation is relatively easy. No prescribed procedures exist for clearing nonexplosive traps. Each trap must be cleared according to its nature.

PUNJI

The punji (Figure 13-11) is one of the simplest traps. It is normally made from locally available material, such as sharpened stakes, nails, or heavy-gauge wire. It is placed in concealed pits or in places that give cover from fire. The enemy normally smears the spikes or cutting edges with excrement or poison. After clearing a punji, sterilize cuts and abrasions immediately and see a medical officer as soon as possible.

Figure 13-11. Typical punjis

CLOSING TRAP

The side-closing trap (Figure 13-12) consists of two wooden slats that are studded with spikes. The slats slide along a pair of guide rods controlled by heavy bands. When the prop holding the slats apart is dislodged, the slats spring together and implant the spikes into the portion of the body passing between them.

Figure 13-12. Side-closing trap

SPIKE BOARD

The spike board (Figure 13-13) is used in a pit and consists of a treadle board with one end spiked. When a man steps on the board, the spiked end flies up and strikes him in the face or chest.

Figure 13-13. Spike board

VENUS FLYTRAP

The Venus flytrap consists of a rectangular framework with overlapping barbs emplaced in a pit. The one shown in Figure 13-14 is made from a metal container that is sunk into the ground until the top is flush. It is then covered with grass and/or leaves. The barbs inflict injury, especially when the victim attempts to withdraw his leg from the trap. These traps are typically located on tracks and along road edges.

Figure 13-14. Venus fly trap

SECTION III. EXPEDIENT DEVICES

Expedient devices are constructed in the field with locally available material. They are employed against vehicles or personnel in the same manner as other mine systems. Expedient devices--

  • Supplement a unit's low supply of conventional mines.
  • Hinder reconnaissance, clearance, and neutralization of minefields.
  • Create enemy attitudes of uncertainty and suspicion to lower morale and slow movement).

AUTHORIZATION

Because expedient devices have nonstandard design and functioning, take special precautions to protect friendly forces. Consider neutralization, disarming requirements, and adequate marking procedures. The use of expedient devices is restricted under the Convention of Conventional Warfare. Expedient devices have the same international restrictions as booby traps. The corps commander is the employment authority for expedient devices. He can delegate this authority to the division commander. If authority is given to use expedient devices, US personnel will adhere to the rules for international law that are applicable to armed conflict.

EMPLOYMENT AND CONSTRUCTION TECHNIQUES

If issued mines are not readily available on the battlefield, expedient devices can be manufactured in the field. Construction varies based on available materials and the ingenuity of the personnel who are fabricating the devices. Expedient devices pose a potential safety hazard to friendly forces--those who are constructing them and those who may later encounter them. Construction should be performed by personnel who are familiar with the materials being used. Innovative designs should be checked and tested before arming and emplacing the devices.

As a minimum, test the fusing mechanism separately to ensure that it functions as designed. Improper fuse operation is the most common cause of malfunction. Also, test the fuse and the firing chain (base charge, blasting cap, and detonating cord) without the main charge to ensure proper operation. Emplace the device after satisfactory performance of the firing mechanism. First, emplace heavy items (such as artillery shells) that are used as the main charge, and then add the firing mechanism. Take care when moving or emplacing expedient devices because their nonstandard manufacture and potentially faulty construction make them highly sensitive to jars and shocks. Construct devices at the emplacement site whenever possible.

Expedient devices are prepared in the field using standard US FDs, detonators, and demolition materials. All devices discussed in this chapter can be made to function electrically or nonelectrically using modernized demolition initiators (MDIs). AP devices must be command-detonated.

HIGH-EXPLOSIVE, ARTILLERY-SHELL ANTITANK DEVICE

The HE, artillery-shell AT device (Figure 13-15) can be readily adapted to expedient mining. Remove the artillery fuse and replace it with a standard FD and a length of detonating cord or with an MDI blasting cap. If properly assembled, a destructor may also be used. If a destructor is not available, firmly pack the detonating cord or place an MDI nonelectric blasting cap into the fuse well with composition C4 explosive.

Figure 13-15. HE, artillery-shell AT device

The device can be activated by a variety of methods depending on the type of FD used. When MDI blasting caps are used, the device is command-detonated. The device can also be adapted to function electrically by adding an electric cap and a power source.

This device can be used as an AT or an AP device. When used as an AP device, it must be command-detonated.

PLATTER CHARGE

The platter charge (Figure 13-16) consists of a suitable container that is filled with uniformly packed explosive and placed behind a platter. The platter is metal (preferably round, but square is satisfactory) and weighs 1 to 3 kilograms. The explosive required is equal to the weight of the platter. The container may not be necessary if the explosive can be held firmly against the platter (tape can be used). The charge should be primed from the exact rear center, and the blasting cap should be completely covered with a small amount of C4 to ensure detonation.

Figure 13-16. Platter charge

The charge should be aimed at the direct center of the target. The effective range (primarily a matter of aim) is approximately 35 meters for a small target. With practice, experienced personnel can hit a 55-gallon drum (a relatively small target) at 25 meters with about 90 percent accuracy.

The platter charge can be used as an AT or an AP device. When used as an AP device, it must be command-detonated.

IMPORVISED CLAYMORE

For the improvised claymore device (Figure 13-17), a layer of plastic explosive is attached to the convex side of a suitably dense, curved base (such as wood or metal). A hole must be made in the exact rear of the base. A blasting cap is placed in the hole to prime the device. Shrapnel is fixed to the explosive with a suitable retainer (cloth, tape, mesh screen).

Figure 13-17. Improvised claymore device

The device must be command-detonated. Command detonation is best achieved with electrical priming or an MDI. A blasting device is attached to the electric cap via firing wires laid at least 50 meters from the device. Ensure that personnel have adequate cover when detonating the improvised claymore.

GRAPESHOT ANTIPERSONNEL DEVICE

Place shrapnel in the bottom of a cylindrical container to make a grapeshot AP device (Figure 13-18). The shrapnel is tamped and held in place with a suitable separator (wadding). Explosive (approximately one-quarter the weight of the shrapnel) is packed to a uniform density behind the wadding. The device is primed in the center of the explosive with an electric cap or an MDI.

Figure 13-18. Grapeshot AP device

This device must be command-detonated. The explosive propels the shrapnel outward from the container. The grapeshot is very effective against personnel targets.

NOTE: The United Nations Convention of Certain Conventional Weapons (CCW) mandates that all fragment munitions produce fragments that are visible by x-ray (such as metal or rock).

BARBWIRE ANTIPERSONNEL DEVICE

The barbwire AP device (Figure 13-19) can be made directional by placing the wire against an embankment or a fixed object. This causes the force of the explosion to expel the barbwire fragments in the desired direction. One roll of standard barbwire is placed into position, and one block of C4 is placed in the center of the roll and primed. This device must be command-detonated.

Figure 13-19. Barbwire AP device



NEWSLETTER
Join the GlobalSecurity.org mailing list