A Report on the 11th Armored Cavalry in Southeast Asia 1969-70

(Reprinted from the January-February 1971 ARMOR ) ARMOR has recorded much of the chronicle of the Blackhorse in Vietnam, both in broad reports by regimental commanders and in articles by other members of the regiment, describing small unit actions. General (then Colonel) William Cobb reported in the March-April 1967 edition of ARMOR, “11th Cavalry Report,” on early Blackhorse operations in Vietnam. In the March-April 1968 edition of ARMOR, “Blackhorse Report II,” Colonel Roy F. Farley continued the coverage from the regimental commander’s viewpoint. General (then Colonel) George Patton described regimental operations from summer 1968 to spring 1969 in the “pile on” articles in the January-February and March-April 1970 issues of ARMOR. Somewhere between the regimental message center and the editor’s “IN” box, Colonel Jimmie Leach’s report on 1969 operations under his command was ambushed, and is still carried missing in action (MIA). Therefore, the present report will sketch in major events during Colonel Leach’s tenure, April through November 1969, as a prelude to describing winter and spring activities during 1969-70, culminating in the entry into Cambodia during May-June 1970. This will preserve at least some of the continuity of ARMOR’s coverage of the Blackhorse in Vietnam. Shortly after Colonel Leach assumed command in April 1969, the regiment moved to northern III Corps, working first with the 1st Infantry Division and later with the 1st Cavalry Division (AM). From May 1969 to mid-June 1970, the regiment was operational control (OPCON) to the 1st Cavalry Division; it was, in effect, that division’s fourth brigade. In conjunction with the shift in operating locale, Colonel Leach moved the regimental command post to Quan Loi in central Binh Long Province, intending to stay a few weeks; it was instead a permanent change of station (PCS) of more than a year. During that year, the regiment ranged through the northern tier of III Corps provinces — Phuoc Long, Binh Long, and Tay Ninh. Blackhorse Base Camp at Long Giao became the home of the 18th Army Republic of Vietnam (ARVN) Division in fall 1969 and the regimental rear took up temporary residence at Bien Hoa Army Base. Later, as 1st Infantry Division units redeployed, the regimental rear took over the 1st Division’s Di An base, closing out of Bien Hoa in April 1970. War Zone “C” in northern Tay Ninh Province, and most of Binh Long and northern Phuoc Long Provinces, have long been camping grounds for regular North Vietnamese army (NVA) units. Throughout 1969 and early 1970, the Blackhorse en- “Winter-spring operations in 1969-70 were aimed at holding NVA units across the border, inter dicting their lines of supply and infiltration into South Vietnam, helping train a strong regional and popular force structure in the south, and continuing to aid the Vietnamese in eliminating the NVA’s infrastructure.”

countered most of the 7th NVA, as well as the 5th and 9th Viet Cong Divisions. Local forces in South Vietnam declined in strength, and by summer 1970, they were capable of no more than harassment and occasional attacks by fire. Allied operations in that area (through September 1969) could be called the “Battle for Binh Long.” Once one of the rich rubber producing areas of the world, Binh Long Province had long been infested with a large number of local and regular NVA forces. At least twice during 1969, the enemy attempted to gain control of the province, attacking the population centers — especially the province capital at An Loc. In the process, Leach sustained heavy casualties and consumed most of his supplies cached along the border in Cambodia. By late fall 1969, NVA units had been driven into Cambodia where they remained in the sanctuary to refit, receive replacement personnel from North Vietnam, and pre-stock supplies for operations in the spring and summer of 1970. By early December, when Colonel Leach left command, he and the Blackhorse had participated in a highly successful campaign to rid Binh Long and northern Phuoc Long of regular NVA units. Winter-spring operations in 1969-70 were aimed at holding NVA units across the border, inter dicting their lines of supply and infiltration into South Vietnam, helping train a strong regional and popular force structure in the south, and continuing to aid the Vietnamese in eliminating the NVA’s infrastructure. Then, on 1 May 1970, the Blackhorse led the attack into Cambodia, and for 2 months, destroyed enemy cache and base systems, and dispersed or eliminated enemy units in the transbor-der bases. Four operational features characterized Blackhorse activities from December 1969 through April 1970:  They were mostly border operations, conducted on extended frontages to reduce infiltration of enemy personnel and supplies from Cambodia into South Vietnam.  Most of these operations encountered regular NVA units since enemy local forces were heavily eroded in strength. As RVN regional and popular forces gained in strength and proficiency, gradually they were able to assume most of the burden of population security and keep the few area Viet Cong tied up.  They made extensive use of land-clearing operations as a means of opening base areas, cutting across infiltration trail networks and providing areas of lateral access for rapid movement of cavalry through the jungle.  They made extensive use of integrated intelligence, reconnaissance, and surveillance operations, augmented by manned and unmanned trail ambush systems, to gather information, interdict enemy movement, and defeat the enemy land-mine threat, which was his most effective weapon against armor. In May-June 1970, the regiment entered Cam bodia with other allied forces to search out and destroy enemy units and base areas. During the autumn of 1969, the 5th VC and 7th NVA Divisions began a prolonged harassment of Bo Duc, capital of the northern district of Phuoc Long Province. Against the possibility of another Duc Lap, two troops of the Blackhorse were air lifted by C130 into nearby Bu Dop in late November. In early December, the 2d Squadron began operations along Highway 14A, from Loc Ninh in northern Binh Long to Bo Duc, to link up with the two air lifted troops and other U. S. and ARVN units defend ing the area. In addition, the 2d Squadron was to interdict the Serges Jungle Highway, a main NVA supply route from Cambodia south to the Song Be River. Squadron operations included extensive land clearing of an access corridor for quick relief of the Bo Duc garrison by armored cavalry. In addition to his squadron, from which F Troop had been airlifted into Bu Dop, Lieutenant Colonel Grail Brookshire’s 2d Squadron had attached to it an engineer land-clearing company, two rifle companies from battalions of the 1st Cavalry Division (AM), and two platoons and company headquarters of the 919th Engineers — the Blackhorse’sown engineer company. With cavalry and infantry protection, the engineers pushed the Rome plows through the jungle, opening a 400-meter wide cut, generally along the trace of Highway 14A, to permit rapid movement of mechanized forces and facilitate airlanding of infantry. At the same time, the 2d Squadron began to interdict the Serges Jungle Highway. For about a week, the enemy rear service group, operating the Serges Jungle Highway, defended their lines of communications, then withdrew, leaving the trails dry, and concentrated on an extensive anti-vehicular mine program against the 2d Squadron. The mine campaign represented an insidious and difficult threat; the Rome plow cut generally paralleled the border, making it possible for mining parties, under cover of darkness, to easily cross the border, plant their mines, and be gone in a few hours. Extraordinary countermine measures were called for; additional mine detectors were procured and put into service, enabling the 2d Squadron to find about four out of every five mines encountered. Recognizing that the best way to defeat mining is to eliminate either the source of the mines or those who plant the mines, Brookshire’s troops began an intensive intelligence and surveillance program to detect the mine-laying parties and eliminate the mine layers. Gradually, these efforts bore fruit in reduced mining incidents; however, it was not until May 1970 that it was possible to get at the source of the mines. In that month, Colonel Ma Sanh Nhon’s 9th ARVN Regiment entered Cambodia, and at the head of the Serges Jungle Highway, captured more than 200 cached mines — the source of Colonel Brookshire’s troubles 6 months before and a continuing problem in the intervening months. At the beginning of 1970, with his lines of communications shut off, his trail systems heavily inter dicted, and his minelaying parties under constant attack, the enemy began to cross the border in battalion strength to ambush friendly units, hoping to destroy a small unit in an ambush before help could arrive. The Battle of the Crescent was typical of these efforts, and is worth recounting briefly since it high lights many characteristics of both antagonists. Early morning on 20 January 1970, NVA gunners opened fire on the 2d Squadron command post near Bo Duc. By mid-morning more than 100 rounds of mixed mortar fire, up to 122mm in caliber, had fallen in and around Colonel Brookshire’s command post, howitzer battery, and tank company laager. The first rounds brought immediate and violent counter-battery fire from the 2d Squadron. A Cobra light observation helicopter (LOH) team already on station swung over to find the mortars, while H Company and one cavalry troop started toward the position. Within minutes, the LOH’s observer located the mortars. Major Fred Franks, the squadron S3, now airborne, began to work the position over with artillery. Tactical air and aerial rocket artillery were both on the way. While fire support poured in on the mortar positions, the LOH was shot down in a crescent-shaped open area in the jun- 50 gle near the Cambodian border. This disclosed the main enemy fighting position — a classic landing zone ambush with six.51-caliber antiaircraft guns, mortars, rocket launcher teams, and an estimated two battalions of infantry. Major Franks shifted artillery into the area immediately and diverted alight fire team to cover a daring rescue of the downed LOH pilot by his covering Cobra, piloted by Captain Carl Marshall. Captain Marshall landed his Cobra amid intense enemy fire, after working over the enemy gun positions with his own ordnance, picked up the injured LOH pilot by dragging him in the front cockpit of the Cobra so that he lay across the gunner’slap, half in and half out of the open canopy, and took off in a hail of hostile fire. Then, the 2d Squadron bore down on the enemy. H Company moved north and west to get between the dug-in NVA and the border. Two troops of cavalry moved through the jungle to close with the enemy from the south and east. While the ground troops maneuvered, Colonel Brookshire kept fire on enemy positions. Sixteen air strikes, more than 20 Cobra loads of ordnance, and more than 600 rounds of 155mm artillery were delivered before the fight was over. Two troops of cavalry broke into the open on the south side of the crescent and charged the enemy positions to their north with all guns blazing. By this time, it was late afternoon and the fight had been knocked out of the 209th NVA Regiment in the crescent. Survivors broke and fled into the jungle toward Cambodia, covered by the lowering darkness. Several features of this action characterize Blackhorse border operations during this period:  The enemy generally consisted of regular NVA forces, which fought as units and enjoyed the same problems with fire support and maneuver coordina tion as any regular force. Their positions were always dug in, weapons were well-sighted and communications, including field wire, were in place before they at tempted to fight. In the Crescent battle, field wire was even found in front of enemy positions along the north edge of the crescent.  NVA commanders were creatures of habit and frequently returned to the scene of a previous fight and set up to fight again — even to the extent of using old bunkers and trench lines.  Fighting this type of enemy called for techniques modified from those used in fighting smaller, more widely dispersed local guerrillas. The Patton “pile on” dictum still applied; however, initial reconnaissance operations had to be conducted in at least platoon strength — lest a small unit take unnecessary losses at the hands of a superior force in a well-organized position before help could arrive.  Proximity to the border made it imperative that the cavalry close with and hold the enemy, lest he escape into the sanctuary. The organic firepower of armored cavalry makes it an ideal force for this type action.  Supporting fires had to be applied in the ap propriate volume at the proper places, then maneu vered about to pace the battle. The ideal situation is to turn everything on when the fight starts — artillery, air, gunships, and maneuver forces — and never turn anything off, but control the battle by varying intensity and place of application of all the resources brought to bear. 51

So successful was the 2d Squadron’s Bo Duc operation that it was decided to carve up War Zone “C” with an extensive series of Rome plow cuts using two squadrons of cavalry and two Rome plow companies. In February, the 1st Squadron, commanded by Lieu tenant Colonel Jim Reed, moved to Tay Ninh, picked up an engineer land-clearing company and commenced operations north toward the Cambodian border. Once along the border, Colonel Reed turned his forces east and moved to link up with the 2d Squadron, which had begun to cut west out of Binh Long Province along the trace of Highway 246. By mid-March, both squadrons had made extensive cuts into enemy trail networks in northern War Zone “C:” the 1st Squadron across the Mustang Trail; the 2d Squadron across the trail systems leading from Cambodia to the Saigon River Corridor. Based on the 2d Squadron’s experience in the Bo Duc operation, tactics and techniques for border inter diction had been fully developed. It was apparent that to defeat the NVA at its own game, one had to make systematic and imaginative use of all resources — especially reconnaissance, intelligence, and surveillance means — and all of these had to be tied into an integrated plan. On the Bo Duc road, Brookshire’s troops had developed an effective ambush system using claymores and other devices in manned and unmanned ambushes (ARMOR, November-December 1970). The system continued to develop and saw full utilization for the first time in War Zone “C” during March and April. Rome plow operations in War Zone “C” included major east-west cuts along the general trace of Highway 246, and along major north-south sec ondary roads. Tactical cuts 100 to 200 meters in width were made along and across enemy trail networks. In addition, base areas were thoroughly plowed out, forcing the enemy to abandon the base. In March, the 165th NVA Regiment was interrupted in the construction of their new “Kennedy Base” in northern War Zone “C” and driven back into Cambodia. From his command post at Fort Defiance, the highest peak (95 meters) in War Zone “C,” Colonel Brookshire directed the 2d Squadron to conduct border interdiction operations, while on his left, Colonel Jim Reed’s 1st Squadron extended the system to the west. By the end of April, these two squadrons had accounted for more than 200 enemy forces killed in the ambush systems along the trails. During the same period, several hundred other enemy soldiers were killed in firefights in the area as the 7th NVA Division fought to reestablish its infiltration system. So great was the enemy’s concern over the presence of the 1st and 2d Squadrons in War Zone “C” that he eventually moved two regiments, the 165th and 209th NVA, around the flanks of the ambush system to attack Colonels Brookshire and Reed from the rear. In April, these units were joined by an antiaircraft regiment whose mission was to force up off the trails the intensive reconnaissance effort of the Blackhorse air cavalry troop. Ground-to-air firing incidents increased to several per day in April. Major Don Smart, the air cavalry troop commander, found himself inadvertently on the ground more than half a dozen times during the month. In addi tion, troop laagers, especially command post laagers, were heavily targeted. Fort Defiance, the 2d Squadron command post, was the objective of several violent attacks. Fortunately, it had become the practice in the Blackhorse to dig in, not a popular procedure with armored cavalry, but a requisite to survival in this environment. Ammunition, aid stations, and personnel shelters were all bunkered in; a perimeter berm added shelter and individual vehicles were dug in as time permitted. The practice paid off. Fort Defiance, on one occasion, survived a 100-round mortar-rocket attack, coordinated with a ground attack by a battalion of the 165th Regiment, with only two friendly casualties. While all indicators lead to a conclusion that the interdiction effort was a success, the full measure of success was not apparent until the Cambodian operation. In May, when the Blackhorse uncovered the cache systems in the Fishhook, extensive stores of food and ammunition were found above ground in temporary storage. Prisoners related that the supplies had not been stored underground because they were scheduled for immediate movement to the south, but had not been moved due to the tight control the 1st and 2d Squadrons exercised over the trail system south of the border. The lessons of these operations confirmed those alluded to before, and added to the conviction that armored cavalry could master the enemy infiltration system with intense use of an integrated intelligence, surveillance, and reconnaissance effort to develop fully the trail system and imaginative use of an extensive ambush system as the basis around which other operations might be conducted. While the 1st and 2d Squadrons were working over the 7th NVA Division in War Zone “C,” the 3d Squadron, with elements of the 1st Cavalry Division (AM), was in Binh Long Province, providing convoy security and escort, and operating along the northern province border in locations vacated by the other two squadrons. The 7th NVA Division continued to try to move elements into the populated areas of Binh Long, de- “Fortunately, it had become the practice in the Blackhorse to dig in, not a popular procedure with armored cavalry, but a requisite to survival in this environment. Ammunition, aid stations, and personnel shelters were all bunkered in; a perimeter berm added shelter and individual vehicles were dug in as time permitted. The practice paid off. Fort Defiance, on one occasion, survived a 100-round mortar-rocket attack, coordinated with a ground attack by a battalion of the 165th Regiment, with only two friendly casualties.” 52 spite the fact that most of the division was fully occupied in War Zone “C.” Typical of these actions was a fight between L Troop and a battalion of the 209th NVA Regiment on 10 March. Binh Long’s rubber plantations were no more than a night’s march from the Cambodian border. Hence, when he chose to do so, the enemy could move at dusk, avoiding the last light air cavalry visual reconnaissance and be in position in the rubber before the first light visual reconnaissance. From there, he could attack towns and villages in the rubber plantations, including the district and province capitals of Loc Ninh and An Loc. On the afternoon of 9 March, Captain John Caldwell’s L Troop set out unmanned automatic ambushes across the trail systems to their west and laagered near the edge of the rubber plantations west of Loc Ninh. During the night, an unmanned ambush detonated. Troop L responded with mortars and artillery; at first light, a check of the area yielded several enemy bodies and considerable equipment, indicating that a larger party had been involved. Captain Caldwell took one platoon and backtracked the enemy trail that lead into the ambush. A second platoon, which had dismounted to search the ambush area, returned to its armored cavalry assault vehicles (ACAVs) herringboned along the edge of the rubber plantations. Before mounting up, the platoon began a search of the nearby rubber plantation to determine if survivors of the ambush had taken up positions. As the dismount party entered the rubber plantation, the enemy opened fire from positions in an old bunker trench line. The dismounted party hit the ground and returned fire from a drainage ditch, while the platoon’s ACAVs returned fire over their heads. The third platoon, hearing the firing, came on the run, closed on a small knoll behind the enemy and cut down would-be es-capees as they ran over the knoll to the rear. The squadron commander, Lieutenant Colonel George Hoffmaster, brought in artillery and gunships as Captain Caldwell returned fire, and L Troop, in a coordinated attack, finished off the boxed-in enemy. The 209th NVA Regiment left more than 50 dead on the field, along with some wounded. Several rubber workers, who the NVA had forced into the bunker line to avoid their alerting L Troop, were freed and their wounds treated. The enemy’s behavior underscored his propensity for coming back to the same place to fight over and over again. Also of note is the fact that in this area, he habitually chose to fight armored cavalry in the rubber, where his losses were enormous (about 40 to 1) compared to fights in the jungle where he had the advantage of being more a creature of the environment than the cavalry. One other feature of this battle that deserves emphasis is the fact that no one in the dismount party was injured by friendly fire, although a heavy volume of automatic weapons fire was directed at the enemy over their heads. For months, the 3d Squadron had concentrated on training battle drills, to include aimed fire and fire discipline. Developed by the squadron commander, Lieutenant Colonel David Doyle, in the fall of 1969, these important features of cavalry operations were con tinued by his successor Colonel Hoffmaster. In this fight, they paid big dividends, driving home the fact that even in combat, units must “A second platoon, which had dismounted to search the ambush area, returned to its armored cavalry assault vehicles (ACAVs) herringboned along the edge of the rubber plantations. Before mounting up, the platoon began a search of the nearby rubber plantation to determine if survivors of the ambush had taken up positions. As the dismount party entered the rubber plantation, the enemy opened fire from positions in an old bunker trench line. The dismounted party hit the ground and returned fire from a drainage ditch, while the platoon’s ACAVs returned fire over their heads.”

have some training programs designed to sharpen basic combat skills. The actions described in this article typify regimental operations from late 1969 to the end of April 1970. The com bination of armored cavalry and Rome plows kept main enemy forces at bay in the sanctuary. All that remained to be done was to enter the sanctuary and destroy bases, supplies, rear service elements, and the main units stationed there. Until about 28 April, the idea of an attack into Cambodia was just that — a good idea. However, by nightfall of 1 May, it was no longer a matter of wishful thinking. Two squadrons, in the midst of the most extensive collection of rice and equipment anyone could remember, were there; and after a day of continual fighting, were in contact with large enemy forces. The Fishhook was to the NVA 7th Division what any large logistics complex is to U. S. forces — supplies of all kinds waiting transshipment to the south, hospitals (with x-ray equipment), laundries, clothing and equipment repair facilities, bicycle assembly, and repair shops. North of the Fishhook were division-sized training and rest areas to house NVA units moving in and out of South Vietnam. Except for some dependent housing (with television), the North Vietnamese lived in Cambodia much as they did in South Vietnam — underground and hidden away in the jungle. Hence, there was still the problem of following the trails, finding the base areas and rooting defenders or survivors out of hiding. By the afternoon of D+2, the 2d and 3d Squadrons had linked up with ARVN airborne division elements, which had conducted airmobile assaults into positions about 20 kilometers deep into the Fishhook to secure key points to the enemy rear. On D+3, the order went out to continue the attack to seize Snuol, the center of a large rubber plantation about 40 kilometers north of the Fishhook. En route, Blackhorse squadrons linked up with two battalions of U. S. airmobile infantry, which were in the process of searching out large cache sites. On D+5, the lead squadron negotiated three blown bridges left by the enemy. By the afternoon of D+5, Colonel Brookshire was on the outskirts of Snuol with lead elements of the 2d Squadron, followed closely by Lieutenant Colonel Bob Griffin’s 3d Squadron. After several days of fighting around Snuol, Brookshire and Griffin were joined by Lieu tenant Colonel Jim Reed and his 1st Squadron. Then the regiment concentrated on a detailed search of enemy base areas, cache sites, and elimination of enemy units remaining in the area. Details of the entire operation are being prepared by the regimental historian and should appear in these pages in the near future. However, one comment is in order here: It has been said that the Vietnam War has made standard military operational methods obsolete and that new planning methods and new tactics are required. While this may be true to some extent, it is instructive to note that in the first 7 days of May, the Blackhorse attacked (from an attack position), crossed aline of departure, proceeded on an axis of advance, linked up with ARVN airmobile infantry, conducted a passage of lines, continued to attack on axes, linked up with U. S. airmobile infantry, conducted another passage of lines, seized a heavily defended objective, and exploited the success by mopping up in the enemy rear. It was noted with considerable relief that no one had forgotten the fundamentals. The Blackhorse Regiment is a unique institution — it does everything well. From vehicle maintenance to operations, it exceeds every expectation. Profes sionalism in all ranks is its hallmark. Its soldiers bear our country’s arms with honor and dignity, despite the difficult tenor of the times. Its fighting record is well known. Strong ties of friendship and professional allegiance bind it to our gallant Viet namese allies. In all these endeavors, the Blackhorse record is unblemished, unexcelled, and unequalled — it reflects the sacrifice of all those of all ranks who have served, who have, whatever the difficulties, done their duty well. No country in history has ever been served so ably by such gallant and dedicated men. Donn A. Starry is a retired four star general. He is a graduate of the U. S. Military Academy, U. S. Army Command and General Staff College, Armed Forces Staff College, and Army War College. His early career includes command and staff positions in the United States, Europe, and Korea, to include commander, 1st Medium Tank Battalion, 32d Armor, Federal Republic of Germany; commander, 11th Armored Cavalry Regiment during the Vietnam War; commanding general, U. S. Army Armor Center and School; commander, V Corps in the Federal Republic of Germany; and commander, U. S. Army Training and Doctrine Command, where he formulated AirLand Battle doctrine, which prepared the Army for warfighting into the 21st century. Starry concluded his career as commander in chief, U. S. Readiness Command, retiring from the Army in 1983; however, his association with the Army and his involvement in national defense policy continued as he served on the Defense Science Board and several other organizations. 54