Fighting the Defile: A Necessary Battle in Restrictive Terrain

A Necessary Battle in Restrictive Terrain Forgotten Frontier Amidst Operations Iraqi and Enduring Freedom, service on another edge of freedom’s frontier seems distant and forgotten. Coined the “forgotten war,” due to its proximity to the leviathan World War II, the Army’s current mission in Korea is relegated to a supporting effort as our Army focuses on tough fights in Iraq and Afghanistan. However, while academic pundits argue over our relevance in Korea’s burgeoning democracy and growing military power, our mission on the ground remains the same — remain relevant and ready to deter North Korean aggression and assist our South Korean allies to defeat North Korea should they choose to break the 54-year-old armistice. Terrain in Korea “The battalions and companies were scattered along the river in weird array, for this was no country for a modern, mechanized army. The hills were not high here, but they were endless. There were no side roads, and no flat spaces anywhere, where command posts, medical aid stations, or anything else could be set up. The hills ran into each other; they overlapped; they blocked vision and hearing in every direction. Because the terrain was compartmented by the hills, some units stood too close to others; others were out of sight and hearing of those supporting them. Wire often did not reach; radios did not work. The units of the 2d Division were not far from each other in yards and miles — but each moved, fought, and worried in almost complete isolation, in a tormented vacuum of its own.”1 The defile fight is essential to success on the Korean battlefield as the terrain is made up of high ground coupled with low-level passage routes. Typically, a defile is defined as a narrow gorge or pass that restricts lateral movement. This restrictive terrain presented a distinct challenge to the armor crewman during the Korean conflict that continues to this day. The majority of Korea is blanketed with hills, which is why tank platoons rarely maneuver in traditional platoon formations, such as the wedge, vee, and online, a source of never-ending frustration to the platoon leader assigned to Korea. Moreover, an armored company will never successfully employ a majority of maneuver techniques and tactics as outlined in U. S. Army Field Manual (FM) 3-90, Tactics.2 In fact, during the Korean war, most tank companies were relegated to infantry support and systematically attached to infantry units as platoons, sections, and tanks. Dividing Korea’s ubiquitous hills are narrow, winding roads that connect most of the rural towns and farmland. In North Korea, many of these roads have unimproved surfaces that only allow the passage of one tank at a time. These meandering roads are key terrain because they provide the only avenue on which mechanized forces and lines of communications can travel quickly from one key city/ town/depot to another. This is not an ideal place for armor crewmen to fight; however, today’s hotspots are not ideal for armor crewmen to fight either.3 Whether it’s the urban areas of Fallujah and Baghdad, the jungles of Joint Readiness Training Center (JRTC), the hills of Lebanon and Korea, or the mountains of Afghanistan, the armor branch must remain agile and adaptive to stay relevant and ready to decisively engage and destroy its nation’s enemies.4 Key Enemy Tactics during a Defile Fight The enemy will employ numerous tactics to ambush, impede, attack, or destroy combat-arms formations, especially in areas that restrict lateral movement. He will 37 by Major William Taylor employ various tactics, such as those below, repeatedly to gain the initiative: Using ubiquitous dead space for ambushes. A defile provides the enemy numerous positions of advantage to ambush an armor unit moving through a narrow passage. Enemy forces will use spurs and heavy vegetation for cover and concealment and position themselves in draws, gullies, ditches, creek beds, and on hilltops for short-range antitank ambushes. Most engagements will be between 25 to 200 meters and occur at a tank’s flank, top, or rear to avoid heavy frontal armor. Vehicle engines will be turned off and antiarmor teams and infantrymen will lie behind cover to avoid detection until they and antiarmor obstacles along the defile road to impede the convoy’s movement and ambush it from multiple sides. For example, as the 2d Infantry Division withdrew from Kunu-ri Village near the Ch’ongch’on River in North Korea, as apart of a general United Nations withdrawal in late November 1950, they ran headfirst into multiple obstacles along a narrow road in the midst of a defile several miles long. On stopping to clear the obstacles from the road, multiple Chinese machine gun positions opened up on the column and engendered an abysmal number of casualties. “Instantly, Charley Heath knew that instead of holding a shallow block along ouflaged tank on a hilltop with an antitank team behind a large berm at the hill’s basin; or a VTT-323 (armored personnel carrier) and antitank team at both flanks.7 The possibilities are endless and the tactic is quite effective. Using an improvised explosive device (IED). The North Korean military is studying the effects of IEDs used against U. S. forces in Iraq and Afghanistan and will most likely use them in a defile fight. Similar to an urban environment, a defile’s 3-dimensional battlespace makes it very difficult to pick up on signatures of an IED emplacement. Excellent positions for IEDs include a winding road, the declivity of a defile, and behind wire or mine obstacles. The numerous rocks, dirt mounds, and vegetation indicative of a defile will make it very difficult to detect IEDs. Using indirect fire. Because a defile canalizes armor movement, it is very easy to employ indirect fire against an armor “The defile fight is essential to success on the Korean battlefield as the terrain is made up of high ground coupled with low-level passage routes. Typically, a defile is defined as a narrow gorge or pass that restricts lateral movement. This restrictive terrain presented a distinct challenge to the armor crewman during the Korean conflict that continues to this day.” hear tanks approaching or bypassing their position. The countless positions of advantage along a defile afford the enemy abundant opportunities to engage multiple tanks, if undetected. Although enemy armored vehicles will only have one position from which to defend, expect dismounted antiarmor teams to make significant use of subsequent and alternate fighting positions along the entire duration of the defile. One might be fortunate enough to slip through one enemy ambush along the defile, but certainly expect to encounter that enemy again, especially if there are further obstacles along the route that impede your movement. Using obstacles to impede movement. The enemy will employ numerous wire the main supply route, the enemy held these ridges at least three miles deep, and they had held them for along time. Long enough to implant machine guns, long enough to set up and register mortars. In a single sickening second, Heath knew the division was speeding into a trap.”5 Using hunter-killer teams. The U. S. Army is not the only military that uses the hunter-killer concept. In a defile, the enemy will use this tactic repeatedly to funnel a tank’s attention to one threat while stealthily wielding another armor-piercing weapon to flank an oblivious crew.6 These hunter-killer teams could take several forms, including a machine gun position in a bunker on a hillside and an antitank team hiding in a creek bed; a cam-column. An enemy entrenched along a defile will maximize use of indirect fire against a column entering, or bogged down, in a defile. The enemy forces will have registered their guns to ensure they are hitting pre-plotted targets with optimal accuracy. The enemy will use indirect fire against an armored force at the defile entrance to attrit the column and separate the formation as it enters the defile. This tactic frightens tank commanders and loaders, which forces them to stay inside their turrets. Inside the defile, the enemy will employ indirect fires to neutralize an armored force when it is halted by a complex obstacle, or suppress the armored column so antitank teams can disable tanks from ambush positions. Using indirect fire limits target acquisition by producing obscuration and potentially damaging the tank’s optics. It will also severely limit the loader’s scanning propensity because he will likely be seeking protection from shrapnel within the turret. Using road craters. Finally, the enemy may employ demolitions, such as road 38 craters, to impede an armor platoon’s movement through the defile. If successfully detonated, the road crater would leave a hole in the road too wide and deep for a tank to maneuver around or through. Expect the enemy to position a road crater at a choke point along the defile where the road is at its narrowest. Also, count on the enemy overwatching this obstacle with an antitank ambush to neutralize the tank platoon as it tries to meticulously back out of the defile. Techniques to Master the Defile Fight Ideally, a combined arms battalion should wage the defile fight. However, combat is rarely fought in ideal conditions, so a company commander must handle a defile at his level. The Korean conflict is steeped with examples of armor companies trying to fight through a defile with little success.8 The following tactics, techniques, and procedures (TTP) for fighting through a defile are from D Company, 1st Battalion, 72d Armor’s recent close combat tactical trainer (CCTT) exercises, mounted defile blank fire exercise, and a combined arms maneuver density at a local training area: Task organization and mission analysis. Fighting through a defile adheres to mission, enemy, time, troops, terrain, civilians (METT-TC). A company commander must do a thorough analysis of the mission, his enemy, his available time, his troop and equipment composition and strength, the terrain, and civilian constraints. During the unit’s recent defile fight, METT-TC was assessed as follows:  Mission: clear a defile.  Enemy: infantry platoon, 3 antitank teams, 3 VTT-323s, 2 T-62s.  Time: roughly 24 hours.  Troops/equipment: 2 M1A1 platoons, 1 M2A2 platoon, 1 infantry squad, 1 M7 fire support team.  Terrain: defile, heavy vegetation.  Civilians: low probability. Plan of attack. Zone reconnaissance; using fires; defile entrance fight; assault through the defile; and defile exit fight. Zone Reconnaissance. Zone reconnaissance of the defile is absolutely pivotal for mission success. Initially, a battalion scout team conducts a zone reconnaissance of the defile high ground with priority intelligence requirements (PIR) “location of antitank teams and obstacles, presence of armored vehicles at the entrance and middle of the defile, and defensive or counterattacking positions at the exit to the defile.”9 We found it useful to have scouts establish alternate bounding observation posts to monitor the defile’s entrance, key terrain throughout the defile, and possible counterattack positions at the defile’s exit. During our mission, however, we had extreme difficulty communicating with the scout team. The scout team was operating on one radio, but was responsible for reporting on multiple nets — including our company. This engendered a lag in communications and effectively limited timely situational awareness of enemy activity. Recommendation: Task-organize scouts to the company-team level for the defile fight. To mitigate lack of reconnaissance, we created two company organic reconnaissance teams. Our first team consisted of one-half of our fire support team (FIST) with a 2-man infantry security team for protection.10 Our second team consisted of the remaining 1(-) infantry squad. Both teams would conduct a zone reconnaissance on opposite sides of the defile’s entrance, middle, and exit. We decided this was an appropriate risk because effective reconnaissance impacted mission success much more than keeping the infantry squad for the main body defile fight.11 The infantry squad(-) had a mission of infiltrating along the high ground to locate and destroy enemy armored vehicles in hide positions with either antitank capabilities or calling in close air support (CAS), rotary gunship fire, or field artillery. The dismounted FIST team was also charged with the task of identifying the PIR listed above, and used similar fire support to destroy armored vehicles nuz-zled in various hide positions. The FIST team and dismounted infantry squad(-) were directed to avoid infantry positions and direct fire contact based on its limited firepower.12 The main objective was to destroy or neutralize antiarmor capabilities within the defile, not to become decisively engaged along the perimeter. Reconnaissance in the defile is essential for mission success. If you do not have access to battalion scouts, consider using a dismounted FIST team and infantry team/squad for reconnaissance purposes. Using fires. After the FIST and infantry teams conduct a thorough reconnaissance of the defile, and the commander senses conditions are met to begin an armored assault, the commander must position reconnaissance teams in key overwatch positions, at the entrance and middle of the defile, to facilitate indirect fires for obscuration and suppression of vehicles that may move out of key positions to engage the main body. Suppressive fires on the defile will help facilitate the main body’s movement into the defile and degrade the target acquisition of enemy ambushes. Recommendation: Do not use too much smoke to obscure movement into the defile. Smoke can obscure the enemy’s movement from hide positions in the hills, giving him the opportunity to engage you “…as the 2d Infantry Division withdrew from Kunu-ri Village near the Ch’ongch’on River in North Korea, as a apart of a general United Nations withdraw in late November 1950, they ran headfirst into multiple obstacles along a narrow road in the midst of a defile several miles long. On stopping to clear the obstacles from the road, multiple Chinese machine gun positions opened up on the column and engendered an abysmal number of casualties.” 39 as you enter the defile. It also limits your FIST and infantry squad’s observation of key positions in the defile.13 Once the armored force has entered the defile, one reconnaissance team (preferably the FIST team) should move to another observation post at the exit of the defile to facilitate fires on any enemy defense, counterattack, or withdrawal. Defile entrance fight. Ideally, the main body attack will begin with an infantry assault along the defile high ground. The M2A2s will provide support by fire at the defile entrance while the infantry dismounts and ascends the high ground to conduct clearing operations. However, if you are not endowed with enough infantry assets to clear the high ground (as in our case since we only had one infantry squad and used them in a reconnaissance role), you can use the M2A2 platoon to establish support by fire at the defile entrance or task organize them within a tank platoon as they fight through the defile.14 If a commander chooses to integrate the mechanized infantry platoon with an armored platoon for the defile fight, the armor platoon in the supporting effort should occupy a support by fire at the defile entrance. Assaulting through the defile. Without infantry support, fighting through a narrow road in a defile becomes a difficult task for a tank platoon. As revealed above, an armor platoon will face many challenges in a defile. Below are some TTP, which were validated during simulation, blank fire, and combined arms maneuver exercises: Formation: The tank platoon will only be able to fight in column formation; recommended order of march includes tank plow, platoon leader’s tank, tank plow (if available), and platoon sergeant’s tank. Load plans: Each tank should have cables attached to rear eyehooks; tanks without plows should have cables attached to front and rear eyehooks. Similar to the confines of an urban area, a defile rarely allows tanks enough maneuver room to pass each other or pivot steer for recovery purposes. Tow cables facilitate a quick recovery, if necessary. Each tank should have two grappling hooks for removing concertina wire obstacles. If not enough grappling hooks are available, the tank platoon should consolidate them on the two front tanks in the column. Each tank should also have a method to mark breached obstacles; using connectors with white engineer tape makes it easy for the loader and tank commander to mark both sides of the obstacle while rolling through at a deliberate speed. Finally, each tank commander and loader should have an M4/16 readily available to fire into dead space. Sectors of scan for a tank crew: Disciplined scanning should be consistent among the tank’s three independent weapons systems — M240,.50-caliber, and main gun or coax. The driver is absolutely vital for mission success and should scan for obstacles in the road, IED signatures, and antitank ambushes in the low ground. Gunners should scan at x3 power with the thermal imaging site; the scan sector depends on how the platoon leader decides to divide the platoon’s scan sectors. The loader’s scan sector is from the front left bumper to the right rear bumper and from the road to the apex of each hill. The tank commander’s scan sector is from the front right bumper to the left rear bumper and from the road to the apex of each hill. The loader and tank commander should anticipate potential ambushes in dead space and have their weapons systems focused on that area should an ambush materialize.15 Sectors of scan within a tank platoon: The lead tank will have the most difficult sectors of scan. Since the lead tank will also act as a breaching tank, the crew must include your best soldiers. The lead tank’s sector of scan will vary depending on the location of draws within a defile. Similar to rooms in a hallway, the lead tank will cautiously pie each draw with its gun tube to ensure it fires the first shot against a suspecting enemy ambush.16 Staff Sergeant Stephen Krivitsky refers to this as the 3-to-6 second advantage. Whoever pulls the trigger first will most likely kill or disable his opponent. Gunners must anticipate each draw, training the main gun on it as the tank approaches the spur protecting it. The gunner should have his main gun ammo selected as ‘HEAT,’ (high-explosive antitank) and set on x3 power. The battle sight for HEAT and SABOT should be set at no more than 300 meters, and the gunner should not lase. Upon detection, the gunner should simply place the enemy within the center of his x3- power sight and pull the trigger.17 The lead tank should also consider dismounting the loader (METT-TC) to recon the draw behind the spur, or cause a diversion so the tank can preempt the enemy ambush (a miniature hunter-killer tactic). The second tank in the column should scan off to the front left and low of the lead tank to kill any close-range antitank ambushes, which might be hidden behind berms or in creek beds, attempting to ambush the lead tank as it rolls by. The areas close in and low to a tank are per- “Zone reconnaissance of the defile is absolutely pivotal for mission success. Initially, a battalion scout team conducts a zone reconnaissance of the defile high ground with priority intelligence requirements (PIR) ‘location of antitank teams and obstacles, presence of armored vehicles at the entrance and middle of the defile, and defensive or counterattacking positions at the exit to the defile.’ We found it useful to have scouts establish alternate bounding observation posts to monitor the defile’s entrance, key terrain throughout the defile, and possible counterattack positions at the defile’s exit.” 40 manent areas of dead space that must be covered by an adjacent tank.18 The third tank in the column should scan off to the front right and low of the lead tank for the same purposes as the second tank. Finally, the fourth tank in the column should provide rear security. Keep in mind that putting the gun tube over the back deck elevates the gun and limits the sectors of scanning for the gunner. In most cases, he will only be able to scan the middle and upper parts of the hill. However, as the rear tank passes draws, the gunner should have his gun tube trained on these possible ambush sites in case a vehicle in a hide position intends to pull out behind the convoy and destroy it from the rear. Reconnaissance by fire: Fighting through a defile is a machine gun intensive battle. Tanks should use a recon by fire for every suspected area of dead space. Recon by fire is very effective in keeping the enemy’s head down, psychologically convincing him that he has been seen, and luring an ambush into a premature and ineffective action. In essence, it is a spoiling attack that impedes an enemy’s desire to initiate an ambush.19 Common operating picture: Detailed graphic control measures (GCM), enemy overlay, and a defile sketch map are good ways to improve a platoon’s common operating picture (COP). A company can use the terrain index reference system (TIRS) to annotate each draw and distinctive terrain features such as hilltops. Odd-numbered TIRS could annotate the western side of the defile, while even-numbered TIRS annotate the eastern side. Platoons could further delineate the complexity of a defile by using alpha, bravo, and charlie terrain; alpha refers to the lower third of a hill, bravo refers to the middle third of a hill, and charlie refers to the upper third of a hill. For example, a potential contact report might sound like, “Contact R-P-G team, T-R-P 3B,” which refers to the third draw on the western side of the defile in the middle third of the hill. Lastly, phase lines can split the defile up between the entrance, apex, exit, or major curves of a road. GCM can also be tied into an enemy overlay; wherever you expect to see an enemy ambush, it would be beneficial to place a GCM to annotate the threat.20 Every crew member should possess an enemy overlay tied to the platoon’s GCM. Since every crew member is responsible for an area of the defile, it is crucial for each one to have the ability to anticipate ambush threats and not rely on constant directions from the tank commander to focus their fires.21 Since each crew member possesses a map of some form, they can also assist tank commanders in calling out enemy locations and current friendly vehicle positions. For example, if a tank commander is in heavy contact with his.50-caliber, a driver can call out a passed checkpoint or phase line to the tank commander or even the platoon. The driver should switch back to intercom immediately after the transmission is sent for safety reasons. Using camouflage: Although most tankers have a deep aversion to using shrubbery to camouflage tanks, it can be an effective measure to conceal a tank’s position in a defile. A tank’s rigid right angles stick out like sore thumbs in a defile environment and only aid an enemy’s target acquisition. Placing vegetation on a tank to break up these rigid edges may mean the difference between a near miss and a direct hit from an antitank ambush. Battle drills: There are several battle drills a tank platoon should perfect prior to fighting in the defile. First, each tank should know how to respond to an IED ambush. In direct-fire battle, calling in an explosive ordnance detachment (EOD) to remove an IED is nonsense. If an IED is spotted, the tank crew should put some distance between itself and the IED, as quickly as possible, and detonate it with a machine gun or HEAT round. The tank crew should also remain alert to the possibility of an antitank ambush in close proximity to the IED. Secondly, the crew should know how to react to wire and mine obstacles. Each tank commander and loader should practice throwing a grappling hook into a wire obstacle (while mounted) and tying the rope to a welded tank part as the tank backs up. Additionally, tank commanders and loaders should be deft at throwing end connectors off the side of the tank to mark an obstacle. Thirdly, tank crews should be proficient at promptly recovering adjacent tanks if they become disabled. Pulling 360-degree security and transmitting breakdown and casualty reports while simultaneously recovering a tank is not an easy endeavor. Finally, the tank platoon should be proficient on evacuating casualties from the defile. This is not an easy task since turning around a tank in a defile is next to impossible. The platoon leader will assign a casualty evacuation (CASEVAC) vehicle (most likely the rear tank), and ensure crewmen are trained on evacuating casualties from one tank to another, and back to the company casualty collection point. Training Strategy to Fight the Defile Fighting the defile is arduous and requires a reservoir of tactical patience, and “The M2A2s will provide support by fire at the defile entrance while the infantry dismounts and ascends the high ground to conduct clearing operations. However, if you are not endowed with enough infantry assets to clear the high ground (as in our case since we only had one infantry squad and used them in a reconnaissance role), you can use the M2A2 platoon to establish support by fire at the defile entrance or task organize them within a tank platoon as they fight through the defile.” 41 commanders should approach this tactical task with meticulous detail and ingenuity. A good approach to this defile fight is training key leaders first. We organized an officer professional development (OPD) session focused on armor platoon and company team TTP on fighting through a defile. We used a briefing put together by the battalion S3, which visually depicted the step-by-step process of a tank and tank platoon fighting through a defile. The briefing thoroughly covered the four tanks’ scanning techniques as the tank platoon moved through the defile; gave examples of how a recon by fire would look; and explained how enemy contacts are identified by using the graphical control measures discussed in this article. We ended our OPD by giving each platoon leader a tactical vignette of a defile in the Republic of Korea, which forced him to apply TTP he learned during the OPD. Each platoon leader had roughly 15 minutes to create a plan before individually briefing the group. We also used the CCTT for simulations training on the defile fight. All three tank platoons were required to maneuver through a defile while the company commander acted as an observer controller. The company commander designed the defile scenario with CCTT technicians and emplaced enemy antitank fire in draws to see how platoons would maneuver and scan. Each platoon experimented with different formations and scanning techniques throughout the day and received a detailed critique from the company commander after each mission. By the end of the day, each platoon had conducted roughly four defile missions. Moreover, each platoon validated the TTP of fighting a defile with an armor platoon. The CCTT served as an invaluable tool for verifying maneuver and scanning techniques prior to training this skill in afield environment. Next, we incorporated the defile fight into a level 2 gunnery rotation at a local live-fire range. On conclusion of our first gunnery on the new tank table VIII, our unit conducted a 2-day defile exercise on an adjacent range.22 The area is a small multipurpose range complex that allows multiple weapons systems to be fired. It is also a prime example of a defile on the Korean Peninsula. Our unit developed a 2-day exercise that focused on an armor platoon’s movement through a defile without infantry or aviation support. Platoons assembled in a company tactical assembly area outside the range to prevent them from viewing enemy positions. The opposition force consisted of troop and wooden vehicle targets, which were organic to the range, as well as alive opposition force (OPFOR) from the company headquarters, mechanic platoon, and sister engineer company. The OPFOR’s capabilities consisted of four RPGs, two IEDs, one M1A1 tank, one M998, one M113, ten infantry dismounts, and three wire and mine obstacles. The commander placed the live OPFOR in numerous draws, bunkers, and the creek bed, as well as hunter-killer teams next to obstacles. The first day was focused at platoon level on day and night dry-fire exercises; the second day transitioned into day and night blank-fire exercises. We changed the OPFOR and obstacles following each iteration to prevent platoons from relaying information to each other after concluding runs. The company commander and first sergeant acted as observer controllers for each platoon and maintained contact with the OPFOR to ensure they reacted with a certain degree of hostility and surprise based on the proficiency of the platoon they were facing.23 Aside from receiving training on movement through a defile and scanning techniques, platoons received valuable training on reacting to wire and mine obstacles without engineer support, how to react to an IED, how to conduct CASEVAC, and how to incorporate a dismounted FIST into their operation.24 We concluded the defile exercise by emphasizing to each platoon the value of having combat multipliers such as infantry in the high ground. Each tank crew gained a better appreciation of the tank’s limitations and how infantry complements armor movement through a defile. Fighting in restrictive terrain is the battle of the present and foreseeable future. Whether this restrictive terrain takes the form of an urban environment or mountainous terrain, today’s armor crewman must mitigate the weaknesses of a tank in this environment. Technology certainly provides U. S. Armed Forces with a desirable edge over militaries of other countries, but the cornerstones of our armor trade will distinguish between success and failure. Armor crewmen must continue to master the art of target acquisition, scanning techniques, battle drills, and using other battle operating systems and personal ingenuity to be successful on this complex battlefield. Notes 1T. R. Fehrenbach, This Kind of War, Brassey’s Inc., Washington DC, 1963, pp. 202-203. 2Headquarters, Department of the Army (HQDA), U. S. Army Field Manual (FM) 3-90, Tactics, U. S. Government Printing Office (GPO), Washington, DC, July 2001, paragraph 3-122 and 3-125. The seven different combat formations are column, line, echelon (left or right), box, diamond, wedge, and vee. A column formation is predominantly used in most parts of the Korean Peninsula (exceptions being the primary invasion routes south and north of the DMZ, the area surrounding Pyongyang, and relatively level terrain in central South Korea). Tactics states that a column formation is used for the following reasons: the best formation to move large forces quickly, especially with limited routes and limited visibility, makes enemy contact with a small part of the total force while facilitating control and allowing the commander to quickly generate mass, provides a base for easy transition to other formations, and for restrictive terrain. 3A defile limits the effectiveness of a tank’s target acquisition and frontal armor by presenting numerous hide positions in a 3-dimensional environment. 4In the Israeli-Hezbollah war of July-August 2006, Israeli Merkava tanks experienced tough battles in the hills of Southern Lebanon against Hezbollah guerrilla fighters with advanced antitank technology procured from Syria and Iran. 5Fehrenbach, p. 222. 6It is human nature to focus all of our senses on a threat that may be harmful. The hunter-killer tactic preys on this tendency in human nature by inducing crew tunnel vision (every crew member fixating on one target). 7North and South Korea could easily emplace tanks in certain keyhole positions on hilltops overwatching a key area of the defile. These positions could be fortified and easily camouflaged. 8Fehrenbach, p. 309. On the afternoon of 24 April 1951, a battalion of Filipinos, led by American tanks was ordered toward Gloucester Hill. The column ground to within less than 2,000 yards of the British before the lead tank caught fire and blocked a defile. Lashed by unbearable fire, the column retreated. Later, the Filipinos tried again, now accompanied by Belgians, some Puerto Rican infantrymen, and tanks from the 8th Hussars. They ran into thousands of Chinese in the hills and “The lead tank will have the most difficult sectors of scan. Since the lead tank will also act as a breaching tank, the crew must include your best soldiers. The lead tank’s sector of scan will vary depending on the location of draws within a defile. Similar to rooms in a hallway, the lead tank will cautiously pie each draw with its gun tube to ensure it fires the first shot against a suspecting enemy ambush.” Continued on next page 42 gorges, and fell back. Also see Fehrenbach, p. 217: a platoon of tanks from the 72d Tank Battalion and one company of the 38th Infantry were sent south to clear the (defile) area; this force was brought to battle along the road and got nowhere. 9Ideally, a company commander would want at least a scout section for a thorough zone reconnaissance of the defile. However, our battalion could only afford to allocate one scout team. 10We took the risk of dismounting half of our FIST team because the M7 FIST Bradley is not an ideal platform for calling accurate fires during a defile fight. It is too loud, the platform is too high, and it cannot easily ascend Korean hills. 11Keep in mind the enemy is comprised of one infantry platoon — much greater than the 3:1 ratio required for an attack against an established defense. 12Using a dismounted FIST team and infantry squad (-) for reconnaissance measures requires tactical patience from the company commander. Infiltrating into a defile takes time and these two reconnaissance teams need to avoid detection to be effective. For most missions, this meant having the main body in a hide position for 2 hours prior to being deployed into battle. 13Pay close attention to the temperature; inversions in the defile will keep smoke close to the ground for long periods of time. 14Similar to an urban environment, an M2A2’s strength in the defile is its elevation scanning capabilities. 15HQDA, FM 3-20.21, Heavy Brigade Combat Team (HBCT) Gunnery, GPO, Washington, DC, September 2009. The new gunnery tables, as explained in FM 3-20.21, are much more suited for fighting tanks in restrictive terrain. 16There is a natural tension between speed and security. High rates of speed in a defile significantly degrades security. As speed increases, the ability to deliberately scan for and acquire targets degrades exponentially. Additionally, a tank crew’s ability to anticipate ambushes is impeded. Conversely, too slow of speed may decrease security by allowing AT/RPG teams to reposition and engage from multiple sides simultaneously. Active, disciplined scanning by all four crew members will mitigate this threat. Fighting the Defile from Page 42 17Staff Sergeant Stephen Krivitsky, “The Three to Six Second Advantage: Tank Combat in Restricted Terrain,” U. S. Army Armor Center and Fort Knox, Fort Knox, KY, 1 April 1997, p. 1-24. This is a critical task when one understands the defender in the defile fight has the advantage of surprise over the attacker. He is holding strong defensive positions at extremely close range due to terrain restrictions. These battlefield annoyances can kill you while you fight through flashing ‘0000’s.’ This occurs when the laser range finder (LRF) cannot accurately identify a specific range to target between 200 and 4,000 meters when firing the main gun, or 25 to 4,000 meters when firing the coax machine gun. The wrong battle sight range for coax and HEAT will cost the gunner and crew time, which they cannot afford to waste. The defender will destroy the attacker once the attacker looses the three to six second advantage. For additional information on the 3-to-6 second advantage, see SSG Stephen Krivitsky, “The Three to Six Second Advantage: Tank Combat in Restricted Terrain,” ARMOR, March-April 1996, pp. 26-33. 18Student Text 3-20.12-1, Abrams Urban Quick Reference Guide, U. S. Army Training and Doctrine Command, December 2002, presents an explanation of tank dead space and the importance of other vehicles of infantry providing covering fire in these areas. 19Krivitsky, p. 16. To conserve main gun ammunition, use tank mounted machine guns in reconnaissance by fire to cause a hidden enemy in the defile to react. The loader or gunner should fire a single burst from their respective M240 machine gun (20 to 30 rounds) while constantly observing for enemy movement, return fire, or the flash of rounds striking metal. The gunner should conduct his recon by fire in 3X, allowing him further scanning of the suspected enemy emplacement. The tank commander should not perform recon by fire with the.50-caliber unless absolutely necessary. When loaded for combat, the.50-caliber has only 100 rounds readily available, and the rounds are typically armor-piercing incendiary with tracer (API-T). These rounds create a flash that could be mistaken for the rounds striking a threat vehicle, and cause the unnecessary expenditure of a main gun round. Reconnaissance by fire is used when other means of enemy detection have been unsuccessful or are unavailable. 20Terrain index reference system (TIRS) is useful to predict ambushes in defile draws. Checkpoints are useful to portray suspected obstacles or IED emplacements along the route. 21A sketch map is an acceptable substitute for crew members if it is a better way to illustrate potential enemy threats in a defile. 22FM 3-20.21; an emphasis on loader M240, TC.50-caliber, short-halt, and battle-sight engagements in the new tank tables greatly assist a tank crew to fight a defile fight — not just an urban fight. 23Each platoon is different based on leader experiences and vehicle composition; for example, only two platoons possessed tank plows. 24After two iterations of using the M7 FIST, we quickly re-validated the importance of dismounting our FIST and using him as an active dismounted observation post (OP). Major William C. Taylor is currently an instructor, Department of Social Sciences, U. S. Military Academy, West Point, NY. He received a B. S. from the U. S. Military Academy and an M. A. from Cornell University. His military education includes Armor Captain Career Course, Armor Officer Basic Course, Scout Leader Course, M1A2 Course, and Military Transition Team Training. He has served in various leader and staff positions, to include battalion staff maneuver officer, military transition team, Tal Afar, Iraq; company commander, D Company, 1st Battalion, 72d (1-72) Armor, Camp Casey, Korea; battalion S3 (Air), Headquarters and Headquarters Company, 1-72 Armor, Camp Casey; and executive officer, B Troop, 1st Squadron, 7th Cavalry, Fort Hood, TX. 43 Publication Title: ARMOR. Publication Number: 0000-2420. Filing Date: 17 September 2010. Issue Frequency: Bimonthly. Number of Issues Published Annually:

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