January the 2nd, 1963. The Meong Delta, 50 mi south of Saigon. The morning mist clung to the rice patties like a ghost, refusing to leave. Captain Lee Tong Ba, commanding officer of the South Vietnamese second armored cavalry squadron, stood at top his M13 armored personnel carrier and surveyed the killing ground at Appbach.
Around him, the smoking hulks of 14 M1 sat silent in the mud. The aluminum bodies were punctured, torn, violated by bullets and rocket propelled grenades. But what disturbed him most were the bodies. 14 gunners. 14 young men who had stood behind their 50 caliber machine guns with nothing but air and optimism protecting them from enemy fire.
The Vietkong had not fled this time. They had stood and fought, and they had learned exactly where to aim. 3 days later, in a maintenance depot outside Saigon, Captain Ba stood before a pile of scrap metal salvaged from the hulls of sunken ships. His mechanics looked at him like he had lost his mind. “You want us to cut shields from shipwrecks and weld them to the tracks?” Sergeant Enuan Vontu asked, using the soldier’s nickname for the M1.
The Americans designed a taxi, boss said quietly, running his hand along the thin aluminum hull of an undamaged M100. We need a tank. What happened next would become one of the most significant battlefield innovations of the Vietnam War. A modification born not from engineering departments in Detroit or design bureaus in Washington, but from desperation, ingenuity, and the brutal mathematics of survival.
The South Vietnamese soldiers, dismissed by American advisers for improvising outside doctrine, were about to revolutionize armored warfare in Southeast Asia. They would transform a vulnerable aluminum box on tracks into a vehicle that could survive the jungle’s most lethal threats. And when the laughter finally stopped, when the skeptics fell silent, the field expedient armor modifications pioneered in the rice patties and rubber plantations of Vietnam would save thousands of lives and fundamentally alter how modern militaries approach
vehicle protection. But first, thousands would die, proving the need. The M1 armored personnel carrier had arrived in South Vietnam on March 30th, 1962, part of the massive military assistance command Vietnam program. 32 of the vehicles fresh from the factory were distributed to two Army of the Republic of Vietnam Mechanized Rifle Companies.
The aluminum hold vehicle represented the cutting edge of American military technology. It was the first mass-roduced aluminum armored vehicle in history. A revolutionary design that prioritized mobility and air transportability over heavy protection. The specification seemed impressive on paper.
The hull was constructed from an aluminum manganese magnesium alloy with armor thickness ranging from 3/4 of an inch to a maximum of 1 and 1/4 in. This provided protection against small arms fire and artillery fragments. The vehicle could carry 11 soldiers plus a twoman crew. It was amphibious, capable of crossing rivers and streams using its tracks for propulsion.
At 40 mph on roads, it was faster than anything the Vietkong possessed. And at $22,000 per unit, it was affordable enough to produce in massive quantities. The original concept was simple and the Pentagon believed sensible. The M113 would serve as a battle taxi. It would transport infantry to the edge of combat where the soldiers would dismount and fight on foot.
The vehicle would then withdraw to a safe distance, returning only to evacuate casualties or reposition forces. The single 50 caliber M2 Browning machine gun mounted on the commander’s cupula was meant for suppressive fire during the approach, not sustained combat. The aluminum armor was sufficient, the designers argued, because the vehicle would never be directly engaged.
The designers had never been to Vietnam. The first indication that reality would not conform to doctrine came on June 11th, 1962 when the two mechanized units conducted their first combat operation. The ARVN soldiers facing the guerilla tactics of the Vietkong quickly recognized that the prescribed dismount and fight method was suicide.
The VC simply melted into the jungle the moment infantry dismounted. By the time soldiers advanced on foot, the enemy had vanished, only to reappear elsewhere. The slow, methodical advance of dismounted infantry played directly into the enemy’s hands. The Vietnamese soldiers adapted. They stayed mounted. They crashed through the jungle at speed, using the M113’s mass and mobility to overwhelm Vietkong positions before the enemy could withdraw.
They treated the vehicle not as a taxi but as an assault platform, a cavalry charge in aluminum armor. The carried infantry became in effect extra crew members in an oversized tank, dismounting only when absolutely necessary. It worked brilliantly until app. The battle of Appback on January 2nd, 1963 shattered the illusion of M113 invulnerability.
1,400 ARVN troops supported by American helicopters and fixedwing aircraft launched an assault against approximately 350 Vietkong fighters from the 261st and 514th battalions. The VC instead of withdrawing had prepared defensive positions and waited. They had studied the M13. They knew its weaknesses.
The aluminum armor that protected against rifle fire crumpled under heavy machine gun rounds. The 50 caliber gunner standing in the open cup was completely exposed. One by one, the gunners fell. 14 men died manning their weapons that day. The M100 without their primary arament became little more than expensive coffins.
The battle ended in humiliation for the ARVN and a wake-up call for American advisers. In the aftermath, while American military analysts wrote reports and debated doctrine, the South Vietnamese soldiers went to work with cutting torches and welding equipment. Captain Ba’s idea, born from desperation at Appach, spread through the ARVN mechanized units like wildfire.
If headquarters wouldn’t provide protection for the gunners, the troops would improvise their own. The first shields were crude. Cut from the hulls of sunken ships in Saigon Harbor. The metal was soft, barely better than sheet steel. But it was something, a psychological barrier if nothing else. The shields were welded around the commander’s 50 caliber position, creating a partial enclosure.
The modification was unauthorized, improvised, and absolutely necessary. The soft shipwreck metal proved inadequate almost immediately. Small arms fire punched through it with ease, but the concept was sound, and the ARVN mechanics refined their approach. They began salvaging armor plate from destroyed armored vehicles, cutting the hardened steel intersections, and fashioning proper gun shields.
By late 1963, the ARVN 80th Ordinance Depot had developed a standardized design producing general issue gun shields for the M13. The shields were simple but effective. a curved piece of armor plate approximately 30 in high and 40 in wide mounted on the commander’s cupula and providing protection from the front and sides.
The gunner could now operate the 50 caliber with his head and upper torso behind steel rather than exposed to enemy fire. Survival rates for vehicle commanders increased dramatically. But the South Vietnamese didn’t stop with gun shields. They added more weapons. Realizing that a single 50 caliber was insufficient for sustained combat, they mounted additional machine guns on the sides of the cargo hatch.
Usually older M1919 A4 machine guns chambered in 306. These weapons gave the M13 firepower on its flanks. The vehicle was transforming from a personnel carrier into something resembling a light tank. The belly of the vehicle presented another problem. Vietnam’s insurgents had developed a sophisticated mine warfare capability by 1963.
Soviets supplied anti-tank mines, improvised explosives, and command detonated charges turned roads and trails into death traps. The M1 and13’s aluminum hull offered virtually no protection against the upward blast of a mine. When an M13 struck a mine, the explosion would tear through the thin floor, killing or maming everyone inside.
The crews began lining the floors with sandbags double layered for maximum protection. Some units also added steel plates beneath the hull, creating rudimentary belly armor. American advisers initially criticized these modifications. They were off doctrine, unauthorized, and made the vehicles heavier, reducing their mobility and amphibious capabilities.
The additional weight stressed the suspension and increased fuel consumption. Some advisers accused the ARVN of cowardice, of hiding behind improvised armor instead of fighting properly. Then the Americans started dying in significant numbers and the criticism stopped. The first major deployment of United States Army ground combat forces to Vietnam began in March 1965 with the landing of Marines at Daang.
The army followed and with them came hundreds of M13 armored personnel carriers. American mechanized infantry and armored cavalry units arrived with factory fresh vehicles operating exactly as doctrine prescribed. They were battle taxis, nothing more. The 11th Armored Cavalry Regiment, the famous Blackhorse Regiment, deployed to Vietnam in September 196.
Before deployment, the units officers toured ARVN mechanized units to learn from their combat experience. What they saw shocked them. The South Vietnamese M113s looked nothing like the pristine vehicles in the army’s technical manuals. They bristled with weapons protected by shields and additional armor.
They operated as fighting vehicles, engaging the enemy mounted rather than dismounting infantry. The American officers were skeptical. This wasn’t how armored personnel carriers were supposed to be used. But the ARVN veterans were blunt in their assessment. Fight from the vehicles or die. One captain told the Americans, “Your choice.
” The 11th Cavalry chose to fight mounted. Before deploying to Vietnam, they requisitioned armor kits based on the ARVN modifications. By 1965, production of standardized armored cavalry assault vehicle kits or ATF kits was underway in the United States and Okinawa. The army had officially adopted the field expedient modifications developed by the South Vietnamese.
The Akev kit was comprehensive. It included a circular armored shield for the commander’s 50 caliber machine gun, providing 360 degree protection. Two additional M60 machine guns, each 7.62 mm, were mounted on either side of the cargo hatch, also protected by armored shields. The kit included hatch armor and improved mounting systems.
Most importantly, it came with belly armor. Steel plates bolted to the underside of the hull from the front, extending halfway to 2/3 of the way toward the rear. The transformation was dramatic. An M113 equipped with an AAV kit went from a lightly armed personnel carrier to a heavily armed assault vehicle. With three machine guns covering overlapping fields of fire, it could engage targets in nearly any direction.
The armor protection, while still far from tank level, was sufficient to defeat most small arms and provide some protection against mine blasts. The first largescale employment of HIV equipped M113s came during Operation Cedar Falls in January 1961. The operation, a massive search and destroy mission in the iron triangle northwest of Saigon, involved the 11th armored cavalry and multiple mechanized infantry units.
The Aclavs performed superbly, providing mobile firepower that could keep pace with the operation’s rapid tempo. They crashed through jungle, forded streams, and engaged enemy positions with devastating effect. But even with the Hav modifications, the mine threat remained. The belly armor helped, but it couldn’t defeat larger mines or command detonated explosives.
Between November 1967 and March 1970, US and ARVN forces lost no less than 1,342 M13s to landmines alone. This figure didn’t include vehicles lost to recoilless rifles or rocket propelled grenades. 73% of all vehicle losses in Vietnam were attributed to mines. The soldiers responded with more field expedience.
Sandbags remained a constant presence. Crews would stack sandbags on the floor, creating a double layer between themselves and any mine blast. The additional weight was significant, sometimes exceeding 1,000 lb, but the protection was worth the tradeoff. Some units went further, adding sandbags to the exterior hole, arranging them as parapits around the cargo hatch and engine compartment.
Titanium plates, salvaged or specially ordered, were added beneath the belly on some vehicles. Titanium’s combination of strength and lightness made it ideal for mine protection, though availability was limited. Most crews made do with steel plate, whatever they could acquire. Maintenance depots became treasure troves of scavenged armor with mechanics trading and bartering for pieces of hardened steel.
The most visually distinctive modification was the addition of chainlink fencing or wire mesh around the vehicle. This improvised standoff armor was designed to counter the RPG7, the Soviet rocket propelled grenade that had become the Vietkong’s most effective anti-armour weapon. The theory was simple.
By creating a gap between the vehicle’s hull and the initial point of detonation, the chain link would cause the RPG’s shaped charge to detonate prematurely before it could focus its penetrating jet on the aluminum armor. The modification was crude but effective. An RPG hitting the chain link would explode several feet from the hull, dissipating much of its energy before reaching the vehicle.
Survival rates against RPG attacks improved noticeably for vehicles with standoff armor. The downside was mobility. The wire mesh caught on vegetation, making movement through dense jungle difficult. It also increased the vehicle’s width, making passage through narrow trails and over bridges problematic. Some units took the concept further, installing hollow steel plating on the sides of the vehicle.
This created a crude form of spaced armor with an air gap between the outer plating and the hull. When an RPG or recoilless rifle round struck the outer plate, it would detonate there and the resulting explosion would have to cross the air gap before reaching the inner hull. The physics of shaped charge weapons made them vulnerable to this countermeasure.
The penetrating jet would disperse crossing the gap, dramatically reducing its effectiveness. The Army Concept Team in Vietnam or ACTiv conducted formal trials of various armor modifications throughout the war. In early 1966, they tested bar armor kits specifically designed for the M1. These kits consisted of metal frames covered with steel bars, creating a cage around the front and sides of the vehicle.
The concept was similar to the chain link modifications, but more robust. Eight M113s received the bar armor kits for initial testing. The frames were substantial, constructed from heavy steel tubing with horizontal bars spaced several inches apart. When deployed, the armor extended 14 in from the sides of the vehicle, creating a standoff distance designed to defeat RPG warheads.
Additional flotation boxes were welded to the sides to compensate for the added weight, ensuring the vehicle retained its amphibious capability. The trials lasted three months from January to April 1966. The 10th Armored Cavalry Squadron conducted 36 combat operations with the modified vehicles.
The results were mixed. The BAR armor was never fired upon by recoilless rifles or RPGs during the trial period, so its primary function remained unproven in combat. What became immediately apparent was the systems effect on mobility. The bar armor made the vehicles 112 in wide in the folded position, 128 in wide when deployed.
Standard Army Bailey bridges in Vietnam couldn’t accommodate this width. Movement through jungle became treacherous with the frames catching on trees and terrain obstacles. Several vehicles suffered damage to the bar armor from striking terrain features. The rotating arm mounts that allowed the side frames to extend outward proved fragile, bending or breaking when struck.
After the trial, ACTV recommended against adopting the bar armor. The mobility limitations outweighed the theoretical protection benefits. The system was abandoned, though individual units continued experimenting with lighter wire mesh and chain link variations that they could add or remove as needed. Despite the official rejection of the bar armor, the improvised armor modifications continued to spread.
Each unit developed its own variations based on available materials, local threats, and operational environment. In the Mong Delta, where amphibious operations were common, units kept modifications minimal to preserve buoyancy. In the central highlands, where mines and ambushes dominated the threat picture, crews piled on every piece of armor and sandbag they could acquire.
The modifications weren’t limited to armor. Some AAVs received 106 mm M40 recoilless rifles mounted on the roof. This weapon, normally carried by dedicated gun jeeps, transformed the Akev into a bunker buster and fortification destroyer. The M40 could fire high explosive anti-tank rounds capable of penetrating 400 mm of armor, though its primary use in Vietnam was against concrete bunkers and reinforced fighting positions.
The weapon proved extremely effective against the hardened fortifications common in areas along the Cambodian and Le Ocean orders. The mounting arrangements for the M40 varied. Some units welded fixed mounts on the roof, sacrificing one of the M60 positions to accommodate the recoilless rifle.
Others created removable mounts, allowing the weapon to be installed when needed and removed for normal operations. The exact number of ACFs equipped with recoilless rifles remains unknown, but estimates suggest several dozen operated throughout the war. Crews also modified their vehicles interiors. The standard M113 had seating along the sides for the 11man infantry squad.
AV crews ripped out most of these seats using the space for ammunition storage. A combat configured ACOV carried staggering quantities of ammunition. 3,000 rounds for the 50 caliber machine gun. Several thousand more for each M60, plus grenades, spare barrels, water, sea rations, crew weapons, tool boxes, and towing cables.
The interior became a fortress of ammunition and supplies, leaving just enough room for the crew to move. This transformation wasn’t universally popular. Infantry officers complained that the AAVI’s ammunitionpacked interior left no room for the infantry squad the vehicle was designed to carry. But armored cavalry commanders argued correctly that they weren’t operating as personnel carriers.
They were cavalry. The mission was reconnaissance, security, and mobile firepower, not troop transport. The infantry could walk or ride on top if they needed a lift. Riding on top of the M13 became standard practice for many units. The aluminum hull offered little protection against mines, and soldiers quickly calculated that they had better survival odds sitting on the roof behind sandbag castles than trapped inside when a mine detonated.
This practice, while contrary to doctrine and intensely frustrating to commanders, reflected the cold mathematics of blast effects. Outside the vehicle, the explosion might throw you clear. Inside, there was nowhere to go. The diesel engine also played a crucial role in survivability. Early M13s used gasoline engines, making them fire hazards when hit.
The ARVN’s gasoline powered M1 13s were particularly vulnerable to catastrophic fires during mine strikes. The transition to diesel power in the M100 A1 variant introduced in April 1963 dramatically reduced this risk. Diesel fuel was far less flammable than gasoline and diesel-powered vehicles were more likely to survive mine strikes without bursting into flames.
Australian forces operating in Vietnam developed their own unique modifications. They experimented with various gun shields and turrets before standardizing on the Cadillac gauge T50 turret which mounted two 30 caliber Browning machine guns or a 3050 caliber combination. The Australians also added aluminum armor plates to the belly of their vehicles, providing additional mine protection without the weight penalty of steel.
The most ambitious Australian modification was the fire support vehicle created by mounting a BA Saladin armored car turret complete with its 76 mm gun on an M13 chassis. This created a mobile direct fire support platform with firepower approaching that of a light tank. The FSV provided crucial fire support for infantry operations, engaging bunkers and fortifications with high explosive rounds.
As the war progressed and the enemy adapted, the Vietkong and North Vietnamese army developed more sophisticated anti-armour capabilities. Soviet supplied AT3 Sagger anti-tank guided missiles began appearing in 1972 along with heavier recoilless rifles and more powerful mines. The M113, even with all its armor modifications remained vulnerable to these weapons, but the field expient armor still saved lives by defeating the more common threats of rifle fire, machine guns, and smaller explosive devices.
The lessons learned from the M1 to13’s combat experience in Vietnam influenced subsequent vehicle design worldwide. The Israeli Defense Forces facing similar threats in the Middle East developed extensive upgrade programs for their M113 fleet. Israeli modifications included small liners inside the armor to protect against fragmentation, armored fuel tanks to prevent fires, and increasingly sophisticated mine protection systems.
Eventually, the Israelis concluded that the M1013 couldn’t be upgraded sufficiently for modern combat and developed the Neymar, a purpose-built heavy infantry fighting vehicle based on the Marava tank chassis. The United States Army’s experience in Vietnam directly led to the development of the M2 Bradley infantry fighting vehicle, which began replacing M13s in frontline combat roles during the 1980s.
The Bradley incorporated many lessons learned in Vietnam, including fighting ports, allowing infantry to fire from inside the vehicle, integrated armor protection designed from the ground up for combat operations, and a powerful 25 mm cannon as primary arament. But the M13 didn’t disappear. Over 15,000 were produced for the US military alone with total production exceeding 80,000 vehicles.
They remained in service with American support units and were supplied to dozens of Allied nations. When the United States invaded Iraq in 2003, M13s returned to combat and the cycle of field expedient armor modification began again. In Iraq, facing improvised explosive devices and rocket propelled grenades, American soldiers once again turned to improvised armor.
They welded additional steel plates to vehicle holes, added sandbags and kevlar blankets, installed slat armor to defeat RPGs, and experimented with any material that might provide additional protection. The army eventually developed official up arour kits, including belly armor plates and bolt-on armor panels, but these were slow to arrive.
In the meantime, soldiers improvised just as they had in Vietnam four decades earlier. The controversy surrounding these improvised modifications in Iraq echoed the debates of Vietnam. Were they effective or merely psychological comfort? Did they provide real protection or just add weight and reduce mobility? Did they indicate inadequate vehicle procurement, forcing soldiers to compensate for design deficiencies with field expedience? The answer proven over decades of combat experience was complex. Improvised armor was never as
effective as purpose-built protection. The additional weight did reduce mobility and increase mechanical stress, but the modifications also saved lives. A soldier behind an improvised gunshield had better odds than one completely exposed. A vehicle with belly armor might survive a mine strike that would destroy an unmodified vehicle.
The protection was imperfect, but perfect was the enemy of good enough. The field expedient armor modifications represented something deeper than mere mechanical improvements. They embodied the eternal dynamic between weapons and armor, attack and defense. They demonstrated soldiers ingenuity when confronted with threats their equipment wasn’t designed to handle.
They revealed the gap between peacetime design philosophy and wartime reality. The modifications also highlighted a fundamental truth about military operations. No vehicle, no matter how well-designed, can be optimized for every threat and every mission. Design is compromise. Weight, protection, mobility, cost, and capability must be balanced against each other.
A vehicle perfect for European planes warfare might be inadequate in Vietnamese jungles. A vehicle optimized for amphibious operations might be vulnerable to mines. There is no universal solution. What matters is adaptability. The M13 succeeded not because its basic design was perfect, but because it could be modified, adapted, and improved by the soldiers who used it.
The aluminum hull that seemed like a liability could be reinforced. The exposed gunner position could be protected. The vulnerable belly could be armored. The single machine gun could become three or more. The vehicle evolved in response to threats, changing faster than any formal acquisition program could manage. The South Vietnamese captain Lee Tongba, standing over those 14 bodies at Appbach in January 1963, understood this truth instinctively.
His superiors might criticize his improvised modifications as off doctrine. American advisers might lecture about proper tactical employment, but doctrine didn’t stop bullets. Proper tactics didn’t prevent mines from detonating. The enemy didn’t care about approved procedures. What mattered was survival. What mattered was bringing your men home.
What mattered was the gun shield that deflected a bullet that would have killed the gunner. The belly armor that reduced the blast that would have crippled the crew. The standoff armor that dissipated the RPG that would have penetrated the hull. By 1970, the improvised modifications that had begun with salvaged shipwreck metal in Saigon had become standard equipment.
The ACIV kit was official Army issue. The M113A1 rolled off production lines with provisions for mounting the additional armor and weapons. What had been field expedient became factory standard. The transformation was complete. The total losses tell the story. The United States, South Vietnam, and Australia lost approximately 8,000 M13s during the Vietnam War.
Between November 1967 and March 1970 alone, 1,342 were destroyed by mines. In 1975, as South Vietnam collapsed, another 1,381 ARVN M1 thines were destroyed or captured. These numbers represented not just vehicles but the crews who operated them, the infantry they carried, the missions they attempted. How many lives did the field expedient armor modification save? The question is unanswerable with precision, but the evidence is compelling.
Survival rates for vehicle commanders increased dramatically after the introduction of gun shields. Crew casualties from mine strikes decreased when belly armor was installed. Units with standoff armor suffered fewer losses to RPG attacks. The modifications worked. Critics argued that the modifications were proof of design failure.
Evidence that the M1 was inadequate for combat. They weren’t entirely wrong. The M1013 was designed as a battle taxi, not a fighting vehicle. Its aluminum armor was optimized for mobility and air transportability, not combat survivability. When employed as an assault platform, fighting mounted rather than dismounted, its limitations became apparent.
But this criticism missed a crucial point. The M11 wasn’t inadequate because its design was flawed. It was inadequate because it was being used for missions it was never designed to perform. The South Vietnamese and American forces needed a light tank or infantry fighting vehicle. What they had was an armored personnel carrier.
So they adapted what they had to meet the needs they faced. This wasn’t failure. This was war. The legacy of Vietnam’s field expedient armor modifications extends far beyond the M113. Modern military vehicles incorporate many of the lessons learned in the rice patties and jungles of Southeast Asia. Miner resistant ambush protected vehicles or MRAPs feature V-shaped hulls designed to deflect blast energy away from the crew compartment.
a sophisticated version of the belly armor improvised in Vietnam. Infantry fighting vehicles include firing ports and overhead protection, allowing troops to fight from inside the vehicle. Gun shields and turret armor are standard rather than improvised, but the fundamental dynamic remains unchanged. Soldiers will always face threats their equipment wasn’t designed to handle.
Engineers and designers will always be several steps behind battlefield reality. The pace of combat evolution will always exceed the pace of acquisition and fielding. When this happens, when the equipment doesn’t match the mission, soldiers will improvise. They will modify. They will adapt.
The sandbags stacked in the belly of an M113 in the Meong Delta in 1967 and the steel plates welded to a Humvey in Baghdad in 2005 are the same response to the same problem. The specific threats change, the technology evolves, but the underlying reality doesn’t. Protection designed for the last war is inadequate for the next one. Soldiers will always need more armor, more firepower, more protection than they have.
And they will create it themselves if they must. The men who welded gunshields in Saigon maintenance depots in 1963 weren’t thinking about military history or doctrine or acquisition policy. They were thinking about the 14 gunners who died at appback. They were thinking about their friends who would be manning those guns tomorrow. They were thinking about survival.
The modifications they pioneered saved thousands of lives over the following decade. That was enough. That had to be enough. Decades later, at reunions and veterans gatherings, former M113 crew members still tell stories about their vehicles, about the armor they added, the modifications they made, the times the improvised protection saved their lives.
They talk about the sound of an RPG detonating against standoff armor instead of the hull. The sensation of a mine blast absorbed by belly plates and sandbags. The relief of manning a gun shield instead of standing exposed. These memories are as vivid as the combat itself. One veteran, a former ACOV gunner with the 11th Armored Cavalry, described his experience simply.
That aluminum hull wouldn’t stop If you were inside when a mine went off, you were done. But we added steel plate underneath. Stacked sandbags on top of that. Wrapped the whole thing in chain link like a Christmas present. Made it heavy as hell. Killed our gas mileage, but it saved my life twice. Hit two mines. Walked away from both.
That improvised armor wasn’t pretty, and it sure as hell wasn’t army standard. but it worked. Another veteran who had served as a vehicle commander with the ARVN third armored cavalry squadron remembered the progression of modifications. Started with just a shield for the 50. Then we added more guns on the sides, then belly armor, then standoff protection.
By the end, my track looked like a porcupine made of steel and sandbags. The Americans used to laugh at us, said we were too scared to fight. Then they started dying and suddenly they wanted to know where we got our armor. The technical assessments and afteraction reports written during and after the war attempted to quantify the effectiveness of field expedient armor modifications.
The conclusions were generally positive but hedged with caveats. The modifications provided marginal improvements against heavy weapons but significant protection against lighter threats. They reduced casualties but didn’t eliminate them. They were better than nothing but inferior to purpose-built armor.
These measured analytical conclusions missed the emotional and psychological dimensions. For soldiers who had seen friends die in unprotected vehicles, any improvement was worth pursuing. The difference between marginally better protection and no protection wasn’t marginal. It was life and death. Perfect became the enemy of good enough.
And good enough kept people alive. The story of field expedient armor in Vietnam is ultimately a story about the gap between what soldiers need and what they’re given. About the difference between doctrine and reality. About the speed at which threats evolve and the slowness of institutional response. About soldiers who refused to accept inadequate protection and did something about it.
It’s also a story about respect. The American advisers who initially mocked the South Vietnamese modifications eventually adopted them wholesale. The army that criticized unauthorized field expedience eventually standardized them as official kits. The design philosophy that prioritized mobility over protection evolved to recognize that survivability mattered more than specification suggested.
The soldiers who improvised armor weren’t ignoring doctrine. They were writing a new one written in welding scars and sandbag stacks validated by survival rather than theory. Captain Lie Tong Ba who pioneered the gunshield modifications after Appbach survived the war. He immigrated to the United States after the fall of Saigon in 1975, eventually settling in California.
In a 1995 interview, he was asked about the modifications he had developed more than three decades earlier. “I was not an engineer,” he said quietly. “I was not a designer. I was a captain trying to keep my men alive. The Americans gave us good vehicles, but vehicles designed for a different war.
We were fighting in rice patties and jungles against an enemy who studied our weaknesses and exploited them. So, we adapted. We changed the vehicles to match the war we were fighting, not the war someone in America thought we should be fighting. Some people criticized us for this. They said we were cowards hiding behind armor. But none of those critics ever stood behind a 50 caliber with bullets coming at them.
None of them ever felt a mine explode beneath their vehicle. If they had, they would have understood. He paused, looking at a photograph from 1964, showing his modified M113, bristling with weapons and armor, sandbags stacked high. We did what we had to do. We saved lives. That’s all that matters. The modifications he pioneered are now displayed in museums, preserved examples of battlefield innovation.
The gun shields, belly armor, and standoff protection that were once considered unauthorized field expedience are now recognized as crucial survival adaptations. Military historians study them as examples of bottomup innovation driven by operational necessity. Engineers examine them as case studies in the evolution of vehicle protection.
Veterans remember them as the reason they came home. In the end, the laughter stopped not because the critics were convinced by technical data or doctrinal arguments. It stopped because the evidence became overwhelming. Vehicles with field expedient armor survived encounters that destroyed unmodified vehicles.
Crews with gun shields lived through firefights that killed exposed gunners. Units that embraced the modification suffered fewer casualties than those that didn’t. The proof wasn’t in reports or studies. It was in body counts, or more precisely, in the absence of body counts. The armor modifications that South Vietnamese soldiers pioneered in the aftermath of Abbach spread throughout the American military establishment over the following decade.
By the war’s end, the ATV kit was as standard as the basic vehicle itself. The improvised had become official. The field expedient had become doctrine, and thousands of soldiers who would have died behind unprotected guns or inside unarmored hulls lived instead, saved by modifications that began with scrap metal and desperate ingenuity.
The mines in Vietnam’s jungles didn’t stop exploding. The RPGs didn’t stop flying. The recoilless rifles didn’t stop firing. But the armor modifications gave soldiers a fighting chance. They deflected bullets that would have killed. They absorbed blasts that would have maimed. They disrupted shaped charges that would have penetrated.
They weren’t perfect. They were never perfect, but they were good enough. And in war, good enough means everything. The M113 armored personnel carrier transformed from an aluminum taxi into an armored assault vehicle by the welding torches and determination of soldiers who refused to die unnecessarily became one of the most successful combat vehicles of the Vietnam War.
Its story is not one of perfect design or optimal engineering. It’s a story of adaptation, of soldiers taking what they were given and making it work, of field expedience becoming standards, of laughter turning to respect. The thunder of artillery may fade. The roar of jet engines may quiet. But the sound of a welder’s torch in a Saigon maintenance depot, creating armor from shipwreck steel, creating life from scrap metal, creating survival from desperation, that sound echoes through military history. It’s the sound of
soldiers refusing to accept the unacceptable, the sound of innovation born from necessity, the sound of lives saved by ingenuity and determination. They laughed at the field armor modifications in Vietnam. They laughed at the South Vietnamese who salvaged shipwreck steel. They laughed at the gun shields and belly armor and standoff protection.
They laughed at the sandbag fortresses and welded plates. They laughed until the modification spread to American units. They laughed until the survival rates proved the concept. They laughed until their own lives depended on the very modifications they had mocked. The laughter died with the first gunner saved by an improvised shield. With the first crew that walked away from a mine strike because of belly armor, with the first vehicle that survived an arpai because of standoff protection, the laughter died and respect took its place. In the end,
that’s what field expedient armor modifications represent. Not perfect solutions or optimal engineering, but soldiers refusing to accept unnecessary death, taking control of their own survival, adapting, improvising, and overcoming. The aluminum boxes on tracks that arrived in Vietnam in 1962 left in 1973 transformed into steel wrapped fortresses bristling with weapons armored against threats their designers never imagined.
The transformation saved thousands of lives. That’s not theory. That’s not doctrine. That’s fact measured in survival rates and casualty statistics. And veterans who came home because a welder in a maintenance depot decided that shipwreck steel was better than hope and a prayer. The jungle mines didn’t stop detonating.
The RPGs didn’t stop flying, but the armor held. The modifications worked. The soldiers survived. And the laughter turned to silence, broken only by the thunder of survival.
