US Army in Vietnam - Countering NVA and VC Ambushes; Security on the Trail


In areas such as the Iron Triangle, trails were unavoidable if moving overland. Similarly the bush and the forest covered flats flanking Highway No. 13 had a network of crisscrossing trails, with as many as five intersections in one acre of ground. In these situations it was almost impossible to move without getting onto a trail. However, despite repeated warnings against the use of trails, with their increased risk of surprise and NVA/VC ambush, the reality was that more than half of the time the U.S. rifle platoon or company was moving it would go by trail either the full distance or at least for some stage of the journey.

Platoon and Company Commanders argued that trails were where to find the VC and the NVA and this argument had a certain elementary logic in its favour provided that maximum security measures when moving by trail were punctiliously observed. Precisely what measures were most effective under varying conditions was a moot subject and almost without standardization or doctrine. As a consequence the young infantry commander often had to feel his way and make his decisions empirically, according to the various pressures bearing upon him.

In the case of the rifle company that was not in file column, but formed more broadly for movement toward the likelihood of contact, the commander had no firm doctrinal guide. As a result of this the formations adopted varied widely. Often, within a single Battalion, there could be as many designs as there were companies for traversing exactly the same piece of terrain.

Al Baker, Company Commander, 4/9th Infantry,

Most of our operations were in flat jungle.  For that terrain, I moved in  a modified V formation with Platoons in column. This formation gave me relative easy of movement. We would never operate on a trail or follow a stream bed or other ambushable feature and it gave me flexibility to maneuver.  No matter where the action originated I could quickly get two platoons with a base of fire and one to maneuver to flank the position.  If the situation did not permit a maneuver, I had a reserve.  I would change lead platoons daily and point men we changed every few hours.  I was always with the lead platoon and just behind the point man.  It was where 95% of our actions initiated.  The point man was always in sight of the platoon.  In most terrain, he was 10-20 meters ahead.  Usually there were two point men. 

"Main trails" or "speed trails" in the Vietnam bush averaged about 3 1/2 feet in width except at intersections. Consequently when a unit went by trail through the heavy bush, it had no alternative except to move in single file. The practical working distance between the point and the front of the main body varied according to the roughness of the terrain and how far one could see ahead. The scouts would be at 20 and 10 meters beyond the van of the point squad, observation permitting.


The point squad itself was generally relieved every hour in order to assure continued vigilance and at each relief it button-hooked into the bush until the main body came up, although this was not the practice if the column was approaching an intersecting trail or streambed or coming to a built-up area. In these instances the scout element (including the point squad) proceeded to check it out, after reporting the sighting to the main body. Its best maneuver was a hook forward through the bush over both flanks that would close beyond the objective, in sufficient depth to abort any ambush (left).

If the main body closed to within sight of the point while it was so moving no real additional jeopardy resulted, provided the column marked time and maintained interval. During such a halt, any attempt by the main body to form a partial perimeter merely caused bunching. Depending on conditions of terrain, visibility, and like factors, the rear of the point could be anywhere from 200 to 50 meters ahead of the lead platoon's front man. At distances of less than 50 meters its security value dwindled since the VC would often let scouts pass an ambush in order to get at the point, or would pass up the point to hit the main body. The double hook forward by the point thus reduced the danger for all concerned.

Nature itself often limited the threat of lateral ambush against a column going by jungle trail as opposed to one going through tall elephant grass or over a path where banks or bushes on either side offered concealment for the enemy. The bush was quite often too thick, so that to put fire on the trail, the field of fire from Claymore or machinegun would be too short and too few targets would he within reach of any one weapon. As a result, a 5 to 10-meter break between squads, which did not retard movement, nonetheless enhanced security.

When making its circular deployment to check out any suspected ambush site, the machinegun often supported the scout element and was best placed with No. 2 man of the point. An alternative to this move was to have the gunner recon the bush forward with fire; if the bush was extra thick, the M-79 would also recon-by-fire. The RT was with the point's last man, who served as breakaway, running the word back should there be instrument failure.


 In those instances where a stay-behind party was dropped off from the column to check on whether it was being trailed, it would peel off from the front of the main body and enter the bush without halting the latter's advance. Its maneuver was S-shaped so that it automatically took up a full ambush posture instead of being a simple fire block (Figure 1). The column would continue to move on and through the stay-behind group (2 fire teams, with a machinegun in the down-trail team). The forward team would spring the trap on the enemy party whilst the rear team fired only if the enemy doubled back or was too numerous for the forward weapons.

Figure 1'Double Hook' Figure 2 'Claymore Ambush'


Other than in attack on road columns, the NVA/VC did not appear to use front-and-rear ambushes, i.e., the delivery of surprise fire from cover by a block up front, quickly followed by an attack on the rear or middle of the column. Except along the wood line of a clearing the almost impenetrable jungle did not lend itself to such tactics in assault against a column moving by trail. More common to the VC and NVA was their use of killing fire from out of concealment against the head of the column from a wide spot in the trail. This was frequently by automatic fire or a command-detonated mine. Their Chicom-Claymore was a potent weapon when so employed. Well hidden and concealed the mine was set to command a long stretch of trail and was one of the major hazards of moving along it (Figure 2).

 There was often no warning and no follow-through; it was a one-weapon affair. During Operation Attleboro, a single command-detonated Claymore set in a tree killed or wounded 26 men strung out over 40-meters of trail. It was fired from 5-meters forward of the front man. The column, which was rushing as a result of battle urgency, and the scout element, did not take enough time to look over the ground thoroughly. The first scout alone had been permitted to pass up the trail beyond the weapon. Obviously the formation, point and the front of the main body, had become closed too tightly. On the wide trail the advance was moving in a fashion that served only to put more people at the mercy of the weapon.


Periodic "clover-leafing" or some variation of that maneuver by the column in movement was supposed to be SOP for field operations in Vietnam. The objective was to beat out a limited area around the base of the command during a security halt or rest halt or before the troops set up the night defence. In this all around sweep four patrols would be sent out anywhere from 100 to 500-meters.

Figure 3 'Correct' Figure 4 'Incorrect'

Among the many cloverleaf variations possible, one quite clearly had obvious advantages. The preferred option (Figure 3) afforded a double check time-wise both forward and rearward of the column's route of advance and made maximum use of the deployment. At all stages of the sweep it also exposed a smaller element to the danger of surprise and ambush. The "buttonhook", used extensively by the Australians for ambushing an enemy force that was following one of their columns, was in essence the covering of one quadrant of the four-circle cloverleaf. It was executed usually over a much smaller radius.


When a company or platoon-size patrol conducted sweeps of the vicinity before setting up for night defence, the priorities were;

If darkness was imminent, the organisation of the position (meaning the assignment of sectors and the placing of men and weapons, but not necessarily digging in) preceded the dispatch of watering parties and the placement of LP's.

Both Division and Brigade commanders constantly contended that the cloverleaf kind of precaution was always taken by patrols, or by a company moving cross-country in search of the enemy. The same story was often told at Battalion. However, analysis of more than 100 company operations at the fighting level revealed that their claims very rarely stood up. Just as trails were used despite all the strict taboos, most of the time little scouting took place outward from the U.S. column traversing them, despite all admonitions.

Contributing to this almost habitual carelessness was the vagueness on the part of many superiors in stating the mission and making it specific as to its several essentials. The unit would often be told simply to "check out" a certain area, or to "run a patrol through the jungle patch ahead and return' as if it were the simple problem of putting a policeman on a beat.


Since it risked considerable hazard to gain something, each patrol needed to have a stated purpose and it should have been told what it was after; Prisoners; Ambushing of the enemy; Destruction of a bridge; Caches; Location of a suspected base camp; Observe signs of enemy movement but not engage; Seek a trail entrance? The list of possibilities was long. But if the average leader was given only a general instruction he would, in most instances, comply in the easiest way, and nine times out of ten that meant taking the trail, probably the same trail going and coming. If he was told at the start, "Be at LZ Lazy Zebra by 1800 for extraction" and he discovered that too little time had been allowed to do anything well, the door was open for him to go forth and do all things badly. Command had to keep itself informed of where its patrols had moved most recently and thus safeguard upcoming patrols against the danger of becoming trapped from having beaten over the same old route.


Military Operations; Vietnam Primer - Dept of the Army, 1967 by Brig.Gen. SLA Marshall (Ret.) & Lt.Col. David Hackworth (Ret.)

Al Baker, Commander B Co, 4/9 Inf, RVN '67 - '68



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