directed energy weapons fm 7-92

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APPEND IX C

DIRECTED-ENERGY WEAPONSThis appendix discusses directed-energy weapons and gives an over-view of how to defend against them. The technical characteristicsof DEW s are given in the Un ited States A rmy capstone manual ondirected-energy weapons and in TB MED 524. This new categoryof weaponry is different in operation and effect from any otherweapon. There is evidence of enemy use of DEW s in areas of conflictaround the world.

C-1. CHA RACTERISTICS

Directed-energy w eapons include lasers, microwave rad iation emitters,

and p article beam generators. These weapons produce casualties anddamage equ ipment by d epositing energy on the target. Conventionalw eapon s rely on th e kinetic/ chem ical energy of a sizable p rojectile todefeat a target. DEWs depend up on subatomic particles or electro-magneticwaves imp acting on the target at or near the speed of light.

a. In the futu re, DEWs w ill be able to dam age on ly soft targets toinclude peop le or soft comp onents of hard targets. Measures to preventdamage or destruction from DEWs engagement to currently fieldedequipm ent and to sold iers are limited bu t are not imp ossible or compli-

cated. Neither the equipment nor the soldiers' apparel have built-inpassive defense mechanisms to counter th e effects of DEWs. Equipm entwill be manu factured with built-in defenses against known DEWs, andolder equipment can be refitted with protective devices.

b. For the present, the reconnaissance platoon can employ the meas-ures discussed in this app end ix to protect themselves from attack byDEWs.

C-2. LASERS

Lasers are the DEWs most likely to be used against US forces. All modernarmies have increasing quantities of laser devices in their inventories. Anylaser-emitting device, such as a target designator or a range finder, can beemployed as a weapon if it is aimed at a type of target it can damage.

a. The m ost probable targets of laser w eapons are op tical andelectro-optical systemsspecifically, fire control devices such as sightsand the sold iers behind the sights.

b. A laser beam entering a d irect-view optical system, such as a tele-

scope, has its pow er increased by the magnification of that system. Anyonewho happens to be looking through the system will suffer burns to the eye(s).The severity of the burns, the permanence of the dam age, and the time

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requ ired for the eye to heal itself depend on w eather cond itions, theintensity of the laser, the m agn ification of the op tical dev ice, and theduration of the eyes exposure to the laser. Eye injury ranges fromtemporary flash blinding and mild burns to total, permanent blindness. Asoldier subjected to this type of injury can be incapacitated and unable to

aim a d irect-fire weapon or track with a comm and -guided weapon. It isanticipated that a laser weapon will fire at a target for a split second atmost before laying on another target.

c. A laser beam entering a non-see-through electro-optical device,such as a night vision sight or thermal imagery device, deposits its energyin the form of heat on the sensor screens inside. If the heat is intenseenough, it can burn out the screen, making the device useless. Some ofthe electrical circuits inside also burn out from the heat and from a sudden

surge of electricity caused by the lasers energy. Any device so affectedwill require extensive repairs.d. Laser weapons can also be d irected against people, but tha t is an

inefficient way to emp loy them. Lasers burn p eople, with the eyes beingthe most susceptible to injury. For the person to suffer eye injury, theymust be looking at the laser source. Since the eye is more sensitive to lightat night, laser energy entering the eye during darkness has a greater effectthan it does du ring daylight. Some types of lasers are hazard ous to theeye even though the laser cannot be seen.

e. Any u ncovered glass surface (such as eyeglasses, vision blocks, orbinoculars) has the potential to attract or alert an antielectro-opticalweapons target acquisition system.

C-3. D EFENSIVE AN D PRO TECTIVE M EASURES

Apply the following techniques to avoid detection by antielectro-opticalweapon systems:

a. Use artillery, mortars, or d irect-fire weap ons to sup press knownor su spected antielectro-op tical weapon s locations. Smoke rou nd s aregood for temporarily defeating laser devices.

b. When operating from fixed or semi-fixed positions in the line ofsight of known or suspected enemy locations, lessen the exposure of glasssurfaces in the direction of the enemy by positioning vehicles and weaponsin covered or concealed positions.

c. When the m ission requires maneuver and , as a result, the possibleexposure of many glass surfaces, block the line of sight between friendlyforces and known or suspected enemy locations with smoke, or plan rou tes

to lessen exposure time.d. Soun d tactics p revent friend ly weap ons locations from being pin-

pointed and targeted for attack by laser devices.

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e. Devices with external glass surfaces not in u se shou ld be sh ieldeduntil the device is used. Even vision blocks and headlights can alertantielectro-optical weapon target acquisition systems; cover the visionblocks as well. Tape, canvas, empty sand bags, or other m aterials can beused as covers.

f. When using optical or electro-optical devices to search for theenemy, use the minimum number possible to do the job and lessenexposure time. Protect the rest until they are requ ired to fire.

g. Gunners can u se the AN/ TAS-4 to scan for enemy laser devices.A blooming of the image indicates the presence of a laser. Gunnersshould be instructed to find and avoid the threat laser device. Indirect fireshould be used to neutralize the devices once they are located.

h. Tubu lar extensions over objective lenses lessen th eir chances of

detection except from almost head on. They can be made from tubu larammun ition packaging or other scrap materials.

i. Low-energy, antielectro-optical weapons work only if they haveline of sight to their target. They are just as effective at n ight as d uringthe day; however, smoke, fog, snow, and dust degrade their effectiveness.Anoth er good coun termeasu re against some laser d evices is to coverone-half of the optical lens with tape or some other typ e of cover. Theremight be some degradation of viewing however, the benefits in reducing

your vulnerability could be great.j. Soldiers should be aw are of the potential hazard from laser devicesin the US Army inventory. Laser range finders are the ones most likelyto be found near friendly soldiers.

k. Laser range find ers are u sed on the M551A1, M60A3, and M1tanks. They are also used in the artillery un its.

Lightw eight target designatorused by ar tillery FISTs for air-borne, ranger, and special forces units.

Ground -locating laser designator in either the ground -mountedor vehicle-moun ted modeused by FISTs for m echan ized, in-fantry, and air assault units.GVS-5, binocular-type laser range finderused by all FISTmembers.Laser designatorused by some attack helicopters to d irect theHellfire and Copperhead systems.Laser devicesused by artillery survey parties for surveying ingun positions.

GVS-5 laser range find ers used by reconnaissance platoons.

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l. Air Force and Navy a ircraft can also carry laser target designatorsfor aiming precision-guided munitions. The F-4, F-7, F-111, F-105, F-16,and A-6 aircraft can be equipped with these designators.

m. Operators of laser firing devices are given extensive training in

their safe employment. The devices themselves cannot be activated with-out conscious, deliberate action on the part of the opera tor. While thepossibility of an accident is extremely remote, it can happen. A victimmight suddenly and un expectedly move d irectly into the path of a laserbeam and look directly at it, or a laser beam might reflect off a shinysurface and strike a victim in the eyes.

(1) To preclude such accidents, operators of laser firing devices mustbe kept constantly aw are of friendly sold ier locations, and they m ustpositively identify targets before lasing th em. Lasers shou ld not be firedat reflective surfaces, and the warning "lasing" should be given beforeactivating the laser.

(2) Conversely, commanders of soldiers operating in areas nearfriendly lasing must ensure that the commanders of laser-operating forcesare always aw are of the locations of friendly sold iers. Soldiers shou ld bebe told if there are friend ly lasers in their area and shou ld be told w herethe lasers are at, if possible. They shou ld be w arned not to look in th edirection of laser-emitting devices unless specifically told it is safe to do

so. Whenever possible, soldiers should wear laser-protective gogglesmatched to the wave length of the friendly lasers. Laser-protective gog-gles are available through normal supply channels.

C-4. D IRECTED ELECTRO M AG N ETIC PULSE

Electromagnetic pu lse is electromagnetic radiation that has a frequencyranging from 10 MHz to 4 GHz.

a. Electromagnetic pu lses can come from nu clear detonations (non-

d irected EMP), from d etonation of conventional explosives coup led withfocusing electromechanical devices, or from electrically powered EMPgenerators on or above the ground .

b. Electromagnetic pulses can damage or destroy sensitive electron iccomponents, such as microchips, coils, and fuses by overloading them withelectrical current. Any equipment containing electronic components issubject to damage or d estruction from EMP attack. FM rad ios aresusceptible to EMP damage. The amount of damage to equipment de-pends on its distance from the source of the pulse.

c. Electromagnetic pu lses can be p rojected into target areas fromlong ranges. They can enter a targeted device through any opening andattack sensitive components inside even if the device is disconnected orturned off. For example, it can enter a rad io set throu gh the louvers over

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the cooling fans and destroy circuitry inside, making the rad io useless. Itcan also enter through unshielded cables for antennas, power lines, andso on.

d. An EMP attack lasts only for a split second and affects a large area.Protecting equipment from its attack is difficult. The only reliable way to

do it is to encase susceptible equipment in some type of heavy gage metalshielding, or to surround it with special metal screening. Burying orcovering it with sandbags or other nonmetallic materials does not provideenough protection. Terrain masking is ineffective because EMP followsthe curve of the earth.

e. When operated from combat vehicles, sensitive equipment shouldbe disconnected if not needed and moved to the center of the vehicle.Smaller pieces of equipment should be placed in empty ammunition cans.

Hatch covers should stay closed unless someone enters or exits thevehicle. By doing this, the equipment is less susceptible to destruction,and the rest is available for use after the attack.

f. Known or suspected locatiom of enemy ground-based EMP-generatingweapons should be attacked by direct or indirect fire weapons within range.

C-5. TRAINING

Commanders at all levels mentally condition their subordinates to facethe threat of DEWs. DEWs appear at first glance to have devastating

effects on men an d equipment; effective defense against them seem snearly impossible. How ever, a basic understand ing of what they are andhow they work reveals them to be less awful than first supposed.

a. Laser, m icrow ave, and EMP w eapons dam age their targets byattacking their soft electronic componen ts. Their term inal effects are lessviolent an d destructive than those of conventional kinetic or chemicalenergy mun itions. Even thou gh they render their targets just as combat-ineffective, they do not have the blast, fire, and fragmentation effects of

conventional munitions. The d angers to peop le are less from laser,microw ave, or EMP attacks than from conventional attacks.b. While the th ought of eye inju ries from lasers is repu lsive to the

soldier, the extent of injury and the recovery time for a laser injury is lessthan that for a gunshot wound. Also, permanent blindness in the effectedeye is not a certainty, and occurs in only a small percentage of incidents.

c. The ad vantages of particle beam w eapons (if they are used) aretheir flat trajectory, long range, and large magazine capacity. Other than

these advantages, they are similar to conventional tank cannons in em-ployment and effect. Whether a vehicle is struck by a HEAT round, anAPDS round, or a particle beam hard ly matters; the effect on th e vehicle

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and its occupants is about the sam e in all cases. There is no coun termea-sure against a particle beam weapon system.

d . Until equipm ent is factory-hard ened against DEWs, the defensivetechniques discussed in this app end ix can provide some p rotection from

d irected-energy attack. DEWs tha t can in ju re p eople are line-of-sightsystems; stand ard defensive techn iques emp loyed against any d irect fireweapon provides equal or better p rotection against personal injury fromDEWS than from conventional weapons, since DEWs have no burstingradius.

C-6. LASER CO UN TERM EASURE SYSTEM

Each squad is issued one LCMS. The LCMS is designed to disrupt enemyoptical and electro-optical sighting devices. The LCMS is capable of

detecting, locating, suppressing, illuminating, and designating enemy op-tical and electro-optical devices. (Figure C-1.)DetectAll optics from extend ed ranges.LocateOptics/ electro-optical devices allowingthe gunner to track and suppress.SuppressTemporarily flashblind eyes usingdirect-view optics, temporarily bloom imageintensifiers, temp orarily flashblind unp rotected ,unaided eyes.IlluminateAt 1,000 meters, the LCMS canillum inate a 30-meter target.DesignateTarget area, cuing and directingfires from other weapons.

a. The p latoon leader uses the LCMS to assist in identifying targetsduring reconnaissance and security operations. Once targets are identi-fied, the LCMS is used to enhance the combat power of the maneuverforce by directing other direct and indirect fires to destroy targets. Thetarget hand off must be coordinated an d specified in the operation order.This ensures the LCMS is not u sed before the availability of han d-offassets. For examp le, if mortars are going to be used to d estroy ident ifiedtargets, the squad will not activate the LCMS until the mortars are readyto fire. If activated too early, the enemy takes measures to counter theaffects desired by the mortars. The LCMS can be used in either the activeor passive mode. When u sed in the passive mode, targets can be identifiedwithout the enemys knowledge. In the active mode, the enemy is aware

that he is being targeted.b. The LCMS gives the p latoon the ability to detect targets at greater

ranges. It shou ld be used in conjunction with other d etection devices.The mission of the p latoon does not change w ith the ad d ition of LCMS.

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The ability to provide tactical information is increased, but the platoonmust use the tactical skills that places them in a position to use the LCMS.For safety, the LCMS shou ld never be u sed to identify friend ly forces.

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