Tactical Smoke Increases Survivability

Tactical Smoke Increases Survivability - by Dr. Gerald C. Holst “It is inconceivable in modern war that tanks should not make use of smoke as Traditional approaches to countering fully as is practicable. Aside from the the antiarmor threat and thereby smoke produced on general by sup- improving vehicle and crew survivabili-porting artillery or aircrafi, ranks should ty have taken the form Of better have smoke immediatelyavailable to them higher lower profile, and for neutralizing hostile antitank guns and improved fire New uver against hostile armored vehicles, and tional approaches to improving sur-for many other purposes. This require-vivability’ l). ment for smoke within tank organization smoke can how it should be produced. Obviously, the can further reduce the probability simplesf way would be to provide smoke of being hit in a vulnerable area. But to shells for the tank cannon. However, the be effective, the smoke system be I OPs covering their withdrawal and mane-screening smoke systems offer addi-immediately brings up the question as to reduce the Probability of being hit and small caliber of the cannon and the limited amount of available ammunition pre-highly efficient, well Placed, and rapidly deployed. Thus, with new tactics, cludes thepossibility of developingan ade- smoke can counter antitank guided quare volume of smoke by this means. (ATGM) and defeat Other A method, which has received advanced electro-optical fire control considerable attention experimentally, is systems. to provide the tank with a smoke-produc-as the smoke off at will. reduce t h e modern battle to a n armored vehicle-vs-armored vehicle THECA VALR Y JOURNAL fight. On the other hand, improved J ~ ~ ~ ~ ~ ,

1930 vehicles will be equipped with sophisticated electro-optical systems that can Smoke tactics as ing apparatus w/lic/l can be turned on and itself are combat multipliers that may 20 may-june 1984 Table 1. Increasing Armored Vehicle Survivability Traditional Approaches Low silhouette Camouflage paints Quieter engines Tactics Higher maneuverability Shoot-on-the-move fire control New armor Complementary Approaches Large area smoke screens Decoy smoke Rapid smoke grenades Vehicle engine exhaust smoke system operate effectively in currently-fielded smokes. The Soviets have acknowledged the use and value of smoke with this assessment: “Now, when the effectiveness of all types of weapons is significantly growing, screening with smoke plays an even more important role in safeguarding the combat operations of troops. It makes observation, aimed fire, and control [of tactical units1 difficult and does not permit the use of infrared, television, laser, and other (viewing) equipment.”2 Based on C. N. Donnelly’s analysis3 of Soviet tactics, the ATGM is probably considered to be their best weapon for supporting the entry of the second echelon into the battle, and smoke is seen by the Soviets as the best way of reducing the effectiveness of NATO long-range antitank weapons. Whenever cover is not available, large quantities of smoke will be used to screen the Soviet attackers and to blind NATO defenders. In fact, the Soviets consider that employing smoke to blind defensive positions will reduce the effectiveness of the defenders’ weapons by approximately 10 times. Actually, the contribution of smoke as a combat multiplier depends upon the effectiveness of friendly as well as Threat electro-optical systems and the tactics used in a smoke environment. Commanders must be fully aware of their own and the Threat weapon’s capability in the smoke environment, and they must be ready to exploit opportunities as they occur. C o m p u t e r i z e d war ga m i n g4 has shown that the use of smoke can reduce friendly losses by 25 percent and slow the enemy rate of advance by 50 percent. Furthermore, tactics and systems used today are derived and improved upon from lessons learned in yesterday’s battles. Smoke Uses Smoke can be used to: 0 Deny the enemy information. 0 Reduce the effectiveness of enemy target acquisition systems. 0 Disrupt enemy movement, operation, and command and control. 0 Restrict nap-of-the-earth and contour approaches for aircraft. . 0 Create conditions to surprise the enemy. 0 Deceive the enemy? There are four general applications for smoke on the battlefield: obscuration, screening, deception, and identification and signaling. Obscuration smoke is applied on or directly in front of the enemy to prevent his observation of friendly maneuvers, to degrade the effectiveness of enemy electro-optical systems (including ATGMs), and to adversely affect the movement of advancing units by causing confusion and by forcing the enemy to deviate from his original plan. Screening smokes are usually placed on friendly positions or between friendly and enemy positions. They allow vehicles to approach long-range antitank and tank weapons unhindered and allow antitank ditches and minefields to be breached. Deception smoke is used to deceive and confuse the enemy. Normally one or more deceptive smoke screens are used in conjunction with an obscuration smoke to deceive the enemy as to friendly force intentions. As the name implies, identification and signaling smokes are used for these purposes. Historical Perspective Although smoke has been used since ancient times, it was not employed systematically until World War I6 when screening and deception to protect the movement of infantry reserves and river crossings from enemy observation were its paramount uses. Notably, in 1917, the British used smoke to screen tanks at the Battle of the Scarpe. Early WW I smokes, which were black, proved unreliable and unstable and were subsequently replaced by white phosphorus (WP). Although the introduction of WP was an innovation in smoke technology, it was used primarily as an incendiary. Concurrent with the introduction of WP, Captain Berger of the French Army developed a pyrotechnic mixture in which carbon tetrachloride and zinc metal reacted to produce a dense white smoke. This mixture was not used either by the U.S. or the United Kingdom (UK) during that war, but it was modified at the beginning of WW I1 to create the well known hexachlorethane (HC) smoke.’ As tactics changed during WW 11, smoke became an asset that could be used offensively. After the war, the Chemical Warfare Board studied smoke effectiveness and noted that whenever it was used, there were fewer personnel and materiel losses. However, t h e use of s m o k e had its drawbacks in that it changed the appearance of natural and artificial terrain and can pinpoint its source as a potential target. The same is true today. In WW 11, it also became apparent that effective smoke deployment depended upon knowledge of terrain, circumstances, geography, wind direction, and meteorological conditions. For example, at the Anzio beachhead, meteorologists provided weather data every hour to ensure that the smoke generators were properly emplaced during the 6 consecutive months that the beach operations were smoked in. This is perhaps the best known and longest smoke screen in history, and it permitted 3,500 tons of supplies to be landed every day to support the defensive operations and the eventual breakout. Elsewhere in Europe, smoke was used extensively for obscuration and deception at river crossings at Arnaville on the Moselle, over the Saar and Roer rivers and at Mainz on the Rhine. In 1944, in the Vysouuho region, a unit of the Soviet tank army used smoke to hide the true site of the San River crossing. WW I1 clearly demonstrated that smoke was very effective in denying enemy observation, thereby degrading the enemy’s direct and indirect firepower. In other applications, dummy and deceptive smoke screens caused the enemy to expend large amounts of ammunition against unprofitable targets. Tacticians also learned that the most effectively generated smoke screen was useless if either misplaced (insufficient time to deploy, wrong wind direction, etc.) or mishandled (insufficient planning, inexperienced operators, poor training, etc.). During the Korean war, smoke was rarely used, probably due to the terrain and to the fact that our troops were usually on the offensive. In Vietnam, smoke was used primarily for signaling and marking locations. Then, with the advent of advanced weapons systems, smoke began to play a more vital role. During the October 1973 Arab-Israeli war, Soviet-made ATGMs destroyed over 130 Israeli tanks of the 190th Israeli Armored Brigade in 2 hours. The Israelis had failed to anticipate the lethality of the AT-3 Sagger in the hands of the Egyptian infantry and nearly lost the battle for the Sinai and Suez Canal with obsolete tactics. However, it was quickly realized that a smoke screen was excellent for blinding ATGM gunners. Once the Israelis began to support their armor with infantry and started using smoke they began to overcome the Sagger. From WW I1 until the 1973 conflict, screening agents received minimal emphasis. However, the lessons learned in the latter conflict forced NATO nations to reconsider smoke as a combat multiplier. The desired smoke agent characteristics, methods of development, and may-june 1984 21

NEAR

INFRARED

VISIBLE

SPECTRAL

WINDOWS

----- ----

WAVELENGTH 0.4

(MICROMETERS)

0.7 1.1 3 5 14 urn 1

IMAGE INTENSIFIERS

ANTI TANK GUIDED MISSILES

TARGET

CURRENT SMOKE CAPABILITY

T ---

SIGHTING AID

AVLB. M88, M1

Table 3. Vehicle Engine Exhaust Smoke System Type of smoke. . Vaporized diesel fuel Cloud height.. . . . . . . . . . . . . . . . . . 10 M Cloud width.. . . . . . . . . . . . . . . . . . . .8 M Time to form effective screen . . . . . . . . . . 5 seconds Cloud duration . Operator determined, Intermittent or continuous Vehicles.. . . . . . . M48A5, MGO-Series,

AVLB. M88. MI

These systems, eitger singularly or in the NAAG prepared a report in which - --- Figure 3. Smoke can be used to degrade laser guidance systems.

may-june 1984 23

GRENADE

RAPID SMOKE SYSTEM

4. These criteria are similar to the desired operating characteristics of the U.S. infrared screening grenade XM76 as specified in the “Requirements Document MN(ED) XMI Tank.” These requirements are also consistent with the RP grenade system now fielded (table 2). The difference is that the XM76 provides protection at all wavelength bands whereas the RP is primarily effective only in the visible and near-infrared bands. This six-nation effort (Belgium, Table 4. Desired Operating Charac- > teristics of NATO Smokes Angular coverage . . . 1 10” to 180” arc Distance from vehicle . . . . .30 to 70 rn Height.. . . . . . . . . . . . . . . . . . . .7 to 12 m Maximum time to smoke production . . . . . .3 seconds Smoke screening time . . . . . . 1 minute I I France, Federal Republic of Germany, Netherlands, Norway and the U.S.) conducted two sets of trials, referred to as Summer Trials and Winter Trials. The Summer Trials were conducted in a setting of green foliage at Bourges, France during September 1982 and the Winter Trials were conducted in a snowy, winter landscape at Raufoss, Norway, during February 1983. These trials were similar to the various annual field trials (Smoke Weeks) hosted by PM Smoke in that state-ofthe-art electro-optical system performance was determined in the smoke environment. Likewise, since Soviet smokes are comparable to standard U.S. smokes it is possible to obtain a relative comparison of U.S. electro-optical equipment against the postulated Soviet smoke-induced environment. As with the Smoke Weeks, the PG 16 trials were designed to: 0 Simulate realistic battlefield operational conditions commensurate with the acquisition of meaningful data. 0 Minimize any variational effect due to major meteorological parameters. The quantitative data produces a data base from which: 0 Future smokes can be referenced. 0 The effectiveness of the smoke for other applications (e.g., mortar, artillery, and pots) can be estimated. 0 The effectiveness of the smoke.in defeating future electro-optical systems can be estimated. During the PG 16 trials, eight smoke candidates, plus a reference standard (the UK-manufactured L8A3 red phosphorus grenade), were tested in 14 trials during the summer and 11 trials during the winter. Thus each system was tested 25 times and, since each system consisted of 8 or 12 individual munitions, over 2,500 individual grenades were expended. This large number of firings covered a variety of meteorological conditions and permitted statistical interpretation of smoke performance. At the PG 16 trials, the U.S. presented two different concepts based upon the infrared screening XM76 grenade. The XM76 provided excellent screening in the visible, near-infrared, mid-infrared, and far-infrared bands. All candidates tested at the trials had a limited capability to defeat enemy passive surveillance and sighting devices operating in the visible and infrared wavelengths. Two significant facts emerged from the trials: 0 A comparison of the summer and winter trials data clearly showed that the mean obscuration time for phosphorus-based smokes (RP) (WP), is drastically lower in the winter environment. This is presumably due to the heavier burning phosphorus particles dropping into the deep snow and being extinguished. 0 Obscurants disseminated by ground-level burning pots generally did not do as well in the winter as in the . summer. The hot pots would melt the snow and the munition would sink. The resultant hole acted as a chimney and changed the dispersal characteristics of the munition. The trials also indicated that airburst-systems such as the L8A3 and XM76 grenades rapidly drift away from a static target. This emphasizes the need for new tactics in which the armored vehicle moves with the screening cloud until natural cover is found. 24 t A smoke screen is created by rapid smoke grenades at NATO field trials, top. Center photo shows initial burst of IR screening grenade while photo above shows same grenade in use at night. ‘These new generation smokes, including the XM76will soon be fielded and will provide protection against enemy infrared surveillance systems. Conclusions Current smoke systems can provide protection against enemy ATGMs and sighting devices operating in the visible through near-infrared and are combat multipliers when appropriately handled and placed. However, if he is to achieve maximum protection, the commander must be fully aware of both friendly and Threat weapon effectiveness in the smoke environment as well as the effects that climate, wind speed, wind direction, time of day, and terrain have on smoke systems. To maintain readiness, training in a smoke environment is essential. The National Training Center (NTC) provides such training by: 0 Conducting tough, realistic combined arms training at battalion task force level, using live fire and opposing forces in realistic scenarios often in a smoke environment. 0 Compiling a data source for training, doctrine, and systems improve-References 1 J. F. O’Bryon, AMSAA, private communication. 2 “Under Smoke Conditions,” by I. Grabovoy, Military Herald. October 1975. 3 “Soviet Ta$ics for Overcoming NATO Antitank Defenses, by c. N. Donnelly, Inremrional De enw Review, August 1979. pg. 1099. [“Smoke Scenarios and Tactics,” by R. J. Washer and LTG Flack. Presented at the Smoke/ Obscurant Symposium IV, April 1982. “Employment of Smoke,” TRADOC Pamphlet 525-3,26 September 1980. “Smoke Screens: An Historical Perspective,” by J. R. Rivello, AMSAA Interim Note 6-48, Aberdeen Proving Ground, MD, August 1977. “Smoke Screening,’’ by P. St. Pierre in Artificial Aerosols, Naval Research Laboratory Memorandum Report 4197,11 April 1983. * “Tank Self-Screening Smoke Systems,” Training Circular 17-15-9,1 December 1981. ment through lessons-learned documents. The NTC also has the instrumentation capability to objectively assess casualties and vehicle kills during training exercises. El sew here, NATO smo ke/obscurants programs are developing a variety of smoke and obscurant materials that will increase battlefield capabilities by: Providing a combat multiplier. Countering new high-technology Threat weapons that are being fielded. Extending smokelobscurant technology into the realm of large-area screening rear area operations. Since there is evidence that smoke can severely degrade the effectiveness of the guidance and control systems of modern weapons, some authors believe that smoke is more effective than high explosives or other suppressive fires in limiting the effectiveness of these systems. A few hundred dollars worth of smoke munitions can prevent a sophisticated missile worth thousands of dollars from hitting its target. Likewise, a few hundred dollars worth of smoke munitions can increase the survivability of our high-technology, high-mobility, armored vehicles. DR. GERALD C. HOLST is the Chief, Obscuration Sciences Section, U.S. Army Chemical Research and Developmen t Center, Aberdeen Proving Ground, MD. He is also the DARCOM Technical Representative to NATO Army Armaments Group Project Group 16 and the chairman of the Project Group 16 Trials Panel. He holds a BSEE from Polytechnic Institute of Brooklyn, an MS and a PhD from the University of Connecticut, and a Masters of Engineering Administration from George Washington University.

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