By Greg Gilbert
In September 1971 4 RAR/NZ (ANZAC) was engaged on Operation Ivanhoe in the north of Phước Tuy Province. On the morning of 21 September D Company made contact with a bunker system in the vicinity of the Núi Lé feature. We suffered casualties, including one Killed in Action (KIA) from the shrapnel from a Rocket Propelled Grenade (RPG), which had been fired at a tree adjacent to the soldier, and found that we had hit a substantial bunker position. I recall hearing the distinctive sound of a North Vietnamese 12.7mm machine gun earlier in the day and wondering what we might be in for. We knew from various intelligence sources that the enemy we were confronting was the 33rd Regiment of the People’s Army of Vietnam (known as the PAVN or NVA), the North Vietnamese regular forces. We withdrew from the bunkers and called in “Dustoff” helicopters to remove the dead and wounded. At the same time I called in artillery fire support and air support from the US Army and US Air Force. During the afternoon a combination of artillery and aircraft at three levels, OH-6 Cayuse (LOH) helicopters at treetop level, AH-1 Cobra attack helicopters, and UH-1D Iroquois gun-ships at a higher level and F4 Phantom and A37 Dragonfly jets at the highest level directed fire onto the bunker system. I remember marvelling at the audacity of the crewman of the LOH. He stood on the skid, completely outside the helicopter with a rifle in his hands and connected only by his harness. The LOH flew at treetop level and I assumed he was seeking to draw fire and determine enemy positions as it would have been difficult to resist taking a shot at him.
Greg Gilbert, Artillery FO with D Company 4RAR/NZ at the battle of Nui Le plots details on a map
Later in the afternoon Major Jerry Taylor, Officer Commanding D Company, directed me to stop the artillery and air support and he called an Orders Group to attack the bunker system. He formed the company up with two platoons side by side at the front with the third platoon in reserve at the rear. Company Headquarters, where I was located, was between the attacking platoons and the reserve platoon.
On Major Taylor’s command the platoons commenced moving forward. We had not progressed very far when the forward platoons entered the bunker system’s firing lanes. Within a very short time we had suffered three KIA to machine gun fire and the whole attack propped. We were unable to progress the attack because of the intense machine gun fire so Major Taylor ordered us to withdraw. Unfortunately we were unable to retrieve our dead comrades because of the intensity of the fire and so, when we withdrew, we had to leave them behind.
We withdrew to the area of the winch point from where we had “dusted off” the dead and wounded earlier in the day, and re-grouped. We were then sent off in a southerly direction, away from the bunker system, in single file. It was my habit as an FO always to count my steps and use my compass to keep track of direction. I worked on the basis that 120 of my steps was equivalent to 100 metres and, using the distance travelled and the direction, I would calculate my position under the jungle canopy by dead reckoning. This day was no exception. Although I was not able to keep track of direction because, by then, night was starting to fall and it was growing very dim under the trees, I did try to count my paces.
We were moving quite quickly through the gathering gloom and our speed and anxiety was increased when messages were received from the rear platoon that the enemy had come out of the bunkers and were closely following us up. A classic NVA tactic was to “grab the enemy by the belt”. This meant getting as close to us as they could on the assumption we would not be able to bring artillery in so close.
We withdrew to the south for a while but unfortunately bumped into another NVA bunker system and drew some small arms fire. It was not clear whether this bunker system was one horn of a two horn ambush layout. All we really knew was that there was intense fire in front of us and the enemy soldiers from the bunker system were not far behind us. The effect was that we concertinaed into a tight group, with the rear elements converging on the leading elements which had halted.
The firing had meanwhile stopped and we formed into a reasonably tight circle. By then it was really quite gloomy so it was very difficult to see exactly where the perimeter of the circle was.
I positioned my forward observer party (signaller and batman) about five to eight metres from Major Taylor who had put his party at the base of a large tree. By this time it was very almost dark under the jungle canopy. I remember feeling relieved that the action seemed to be over and pulled out my map to plot our location and plan our defensive fire tasks for the night as best I could in the dim and fading light. (Defensive fire tasks were possible targets communicated to the gun battery which would work out the calculations for firing in advance so that response time would be quicker in the event of an attack during the night.) Just as I did so, the Company was assailed by a fusillade of withering small arms fire from, it seemed, all sides. My map was dropped and we all flattened ourselves on the ground. Under intense fire like this, it was imperative for me to call in artillery fire support in the shortest possible time. However, I had a major problem. I had no idea where we were as I had not had time to work it out on my map and under the canopy it was too dark to see it. These circumstances were dire enough but were compounded by the fact that I was unable to speak to the Company Commander who was about eight metres away from me to coordinate our actions. Every time I yelled I drew a volley of green tracer fire directed at where the enemy thought my voice was coming from. We appeared to be surrounded and the diameter of our circle was small enough to enable the enemy, holding our belts, to hear my voice. If we were to survive I realised that it was all up to me to get artillery quickly and accurately.
A further problem was the position of the guns relative to us. 104 Battery, which had six guns, had been split into two sections of three guns at two separate Fire Support Bases (FSB). The guns from one FSB, FSB Robin to the south west, were out of range and we were close to the maximum range of the guns at FSB Debbie to the west. These guns would be firing towards us and the dispersion of the rounds (statistical distribution of the fall of shot) would be large along the line of fire and the shrapnel would come towards us when the rounds exploded if they landed on the guns’ side of our position. There was also the risk the rounds could land on us because of the dispersion pattern. It was therefore important to me that I positioned the fall of shot so that it didn’t kill us all. The way to do that was to have the initial rounds land to the north so that any dispersal of the rounds would be parallel to us and not toward us. But it also had to be close enough so that I could adjust it as close as I could in the least amount of time. And time was of the essence, given the incoming rifle and machine gun fire we were receiving.
I had already realised that my map was useless and that if I were going to call in artillery fire I would have to work it out in my head. All the while I was lying on the ground, in fact, pressed as close to the ground as I could possibly get and was observing tracer bullets directed at me and passing about 30 cm above me. I assumed that the NVA knew that someone (me) would be trying to call in artillery fire.
I knew I had to determine my location as accurately as I could so that the target information I passed to the guns wouldn’t be our own location and would not result in my shelling ourselves. As I said, I knew approximately how far I had walked and the vague direction. What I did was as follows. I reasoned that I could regard the path we had taken as the hypotenuse of a right angled triangle, though our path was not exactly straight. The other two sides of the triangle would be the distance I had moved in terms of Eastings (East-West) and Northings (North-South). From the hypotenuse I reckoned I could calculate the other two sides of the triangle using Pythagoras’s theorem that the square of the hypotenuse was equal to the sum of the squares of the other two sides.
I knew we had walked further south than east so I made my assumption that the north/south side of the triangle would be long and the east/west side short. My starting point was where we had had the ‘Dustoffs’ during the day. I had been calling in air support so hoped I could sort of recall the grid reference of that location, but I was not positive I could recall it accurately. I then took my hypotenuse figure, the distance we had walked, and solved the triangle to obtain the other two sides. One side became the distance in Eastings we had walked and the other the distance in Northings. I then had to add my easterly estimate to the Eastings of the original grid reference to obtain the first half of my new location grid reference. Then keeping that half of the new grid reference in mind, I subtracted my southerly estimate from the Northings of the original grid reference to obtain the Northings figure for my new grid reference. I thus calculated, as best I could with tracer bullets flying over my head, and without being able to use a map or a piece of paper, our current location.
I had a signaller with me and the usual practice would have been for me to pass my commands to him and he would write them down and relay them to the guns over the radio. However, such practices were not appropriate here, given that my voice had already drawn aimed fire, and I didn’t want the signaller having to remember everything I told him because he couldn’t write it down, so I elected to pass the fire orders to the guns myself, striving to achieve a balance between being heard and understood by the gun position and not being heard by the NVA and drawing aimed gun fire at my voice.
Using my newly-calculated current location I then worked out a new grid reference by simply changing the Northings for the guns to be aimed at to allow a margin of error in case I had been wildly inaccurate in my calculations and had aimed the guns at myself. I then called in the fire. Even then I wasn’t confident that the rounds would not land on me. The gun position had told me that the time of flight of the rounds would be 22 sec and I will confess that once the guns had reported “Shot” over the radio, meaning they had fired, the following 22 sec was the longest in my life.
To my relief the rounds did not land on us and I then proceeded to adjust the fall of shot closer, a procedure known as Danger Close. Normally the rounds would be adjusted in along a compass bearing from the forward observer to the target. Because I had no way to obtain direction from me to where the rounds landed, I used the cardinal points of the compass and from that was able to obtain a rough idea of orientation from the sounds of the rounds landing. I brought the exploding rounds closer until live shrapnel from them was smashing through the trees above us and dead shrapnel was falling on us. When an artillery shell explodes the shell fragments are termed live shrapnel when they are powered by the force of the explosion. When they have expended this initial energy and are falling to earth under the influence of gravity they are termed dead shrapnel. Although I couldn’t see where the rounds were landing, I could certainly hear them. From experience I knew that, when the sound of an artillery shell exploding changed from a “boom” to more of a “crack”, it was exploding about 30 metres away. When I heard the crack I knew that this was as close as I could bring the fire without endangering our own troops. I then adjusted the fall of shot so that the shells moved around our perimeter. These were very hazardous circumstances. I was as close to the earth as I could be, lying there with a handset against my ear, trying to concentrate on safely adjusting the battery fire while trying to avoid being heard by the enemy and being extremely conscious of the green tracer bullets zipping just above my head.
By seven or eight o’clock it was clear that the two horns had closed and trapped us. We were surrounded.
Firing from the NVA had started to ease off when the artillery started and by about 21:00 enemy fire had all but petered out. However, to keep up morale and give the company a feeling that we were not isolated or abandoned, I maintained firing at a low rate until about 01:00 on 22 September. My final instructions to the guns was to keep the guns laid on the last target ready to fire for the attack which we all thought would come at dawn.
We all expected a dawn attack, however, dawn came and there was no sign of the North Vietnamese apart from one dead soldier who had died quite close to us. The NVA had taken their dead with them except for this soldier who lay about eight metres from where I had lain. He died with a loaded rocket propelled grenade launcher on his shoulder and his finger on the trigger. We surmised that he was about to shoot at the large tree at company headquarters but was hit by our artillery shrapnel or one of our machine guns before he could do so.