Battle of Long Tan

The Battle of Long Tan (18 August 1966) took place near the village of Long Tan, in Phuoc Tuy Province, South Vietnam during the Vietnam War. The action was fought between Australian forces and Viet Cong and North Vietnamese units after 108 men from D Company, 6th Battalion, Royal Australian Regiment (6 RAR) clashed with a force of 1,500 to 2,500 men from the Viet Cong 275th Regiment, possibly reinforced by at least one North Vietnamese battalion, and D445 Provincial Mobile Battalion. The 1st Australian Task Force (1 ATF) arrived between April and June 1966, constructing a base at Nui Dat. After two months 1 ATF had moved beyond the initial requirements of establishing itself and securing its immediate approaches, beginning operations to open the province. Meanwhile, in response to the threat posed by the Australians the 275th Regiment was ordered to move against Nui Dat. For several weeks Australian signals intelligence had tracked a radio transmitter moving westwards to a position just north of Long Tan; however, extensive patrolling failed to find the unit. At 02:43 on the night of 16/17 August Nui Dat was heavily bombarded by mortars, recoilless rifles (RCLs) and artillery fired from a position 2000 m to the east. Although the Viet Cong were expected to have withdrawn, a number of company patrols would be dispatched. The following morning B Company, 6 RAR departed to locate the firing points and the direction of the Viet Cong withdrawal. A number of weapon pits were subsequently found, as were the positions of the mortars and RCLs.

Around midday on 18 August, D Company took over the pursuit. At 15:40 the lead platoon clashed with a Viet Cong squad, forcing them to withdraw. Shortly after resuming the advance, 11 Platoon came under small-arms and rocket propelled grenade fire at 16:08 from a company-sized force after drawing ahead of the other platoons and was isolated. Pinned down, they called for artillery support as a monsoon rain began, reducing visibility. Beginning as an encounter battle, heavy fighting ensued as the advancing Viet Cong attempted to encircle and destroy the Australians. After less than twenty minutes more than a third of 11 Platoon had become casualties, while the platoon commander was killed soon after. 10 Platoon attempted to move up on the left in support but was repulsed. With D Company facing at least a battalion, 12 Platoon tried to push up on the right at 17:15. Fighting off an attack on their right before pushing forward another 100 m they sustained increasing casualties after clashing with several groups moving around their western flank to form a cut-off prior to a frontal assault. They opened a path to 11 Platoon yet were unable to advance further and threw smoke to mark their location. With D Company nearly out of ammunition, at 18:00 two UH-1B Iroquois from No. 9 Squadron RAAF arrived overhead to resupply them. Meanwhile, the survivors from 11 Platoon withdrew back to 12 Platoon during a lull, suffering further losses. Still heavily engaged, both platoons returned to the company position covered by the artillery.

By 18:10 D Company had reformed but was still in danger of being overrun. A Company, 6 RAR was dispatched in M113 armoured personnel carriers from 3 Troop, 1st APC Squadron to relieve them. Meanwhile, B Company was still returning to base on foot and was also ordered to assist. Departing Nui Dat at 17:55, the relief force moved east, crossing a swollen creek before encountering elements of D445 Battalion attempting to outflank D Company and assault it from the rear. The Viet Cong were caught by surprise as the cavalry crashed into their flank and with darkness falling they broke through at 19:00, while B Company entered the position at the same time. Arriving at a crucial point, the relief force turned the tide of the battle. The Viet Cong had been massing for another assault which would have likely destroyed D Company, yet the firepower and mobility of the armour broke their will to fight, forcing them to withdraw. The artillery had been almost constant throughout the battle and it proved critical in ensuring the survival of D Company. By 19:15 the firing ceased and the Australians waited for another attack. However, after it became clear no counter-attack would occur, they prepared to withdraw 750 m west from where their casualties could be extracted by helicopter. With the dead and wounded loaded onto the carriers D Company left at 22:45, while B and A Company departed on foot. A landing zone was then established by the cavalry with the evacuation of the casualties finally completed after midnight.

Forming a defensive position ready to repulse an expected attack the Australians remained overnight, enduring the cold and rain. They returned in strength the next day, sweeping the area and locating a large number of Viet Cong dead. Although initially believing they had suffered a major defeat, as the scale of the losses suffered by the Viet Cong were revealed it became clear they had in fact won a significant victory. Two wounded Viet Cong were killed after they moved to engage the Australians, while three were captured. The missing men from 11 Platoon were also recovered; their bodies found lying where they had fallen, largely undisturbed. Two of the men had survived despite their wounds, having spent the night in close proximity to the Viet Cong as they attempted to evacuate their own casualties. Due to the likely presence of a sizeable force nearby the Australians remained cautious as they searched for the Viet Cong. Over the next two days they continued to clear the battlefield, uncovering more dead as they did so. Yet with 1 ATF lacking the resources to pursue the withdrawing force, the operation ended on 21 August. Despite being heavily outnumbered, D Company held off a regimental assault supported by heavy artillery fire, before a relief force consisting of cavalry and infantry fought their way through and forced the Viet Cong to withdraw. Eighteen Australians were killed and 24 wounded, while the Viet Cong lost at least 245 dead which were found over the days that followed. A decisive Australian victory, Long Tan proved a major local set back for the Viet Cong, indefinitely forestalling an imminent movement against Nui Dat and challenging their previous domination of Phuoc Tuy Province. Although there were other large-scale encounters in later years, 1 ATF was not fundamentally challenged again.

Military situation
The Australian Army Training Team Vietnam (AATTV) had been assisting South Vietnamese forces since 1962 as part of the wider US advisory effort; however, in April 1965 ground troops were committed as the worsening situation in Vietnam led to a significant escalation of the war. The 1st Battalion, Royal Australian Regiment (1 RAR) was dispatched with engineers, cavalry, artillery and aviation elements in support, totalling 1,400 personnel. 1 RAR would be attached to the US 173rd Airborne Brigade based in Bien Hoa, a formation which operated throughout III Corps Tactical Zone (III CTZ). Unlike later Australian units that served in Vietnam which included conscripts, it was manned by regular personnel only. The battalion would be employed in airmobile search and destroy operations using helicopters to insert light infantry and artillery into an area of operations (AO) and support them with mobility, fire support, casualty evacuation, and resupply. Commencing operations in late June, 1 RAR conducted forays into War Zone D and the Iron Triangle where they fought a number of actions including the Battle of Gang Toi on 8 November and Operation New Life in the La Nga Valley, 75 km north-east of Bien Hoa between 21 November and 16 December. Operation Marauder was launched on the Plain of Reeds in the Mekong Delta on New Years Day 1966 and continued until 7 January. 1 RAR then took part in Operation Crimp in the Ho Bo Woods, north of Cu Chi over the period 8–14 January. Further fighting followed, including the Battle of Suoi Bong Trang on the night of 23/24 February 1966.

At the strategic level, the Army of the Republic of Vietnam (ARVN) and the South Vietnamese government had both rallied after appearing on the verge of collapse and the threat to Saigon subsided by late 1965. Yet further troop increases were required if General William Westmoreland, Commander US MACV, was to adopt a more offensive strategy, with US forces planned to rise from 210,000 in January 1966 to 327,000 by December. The Australian government increased its own commitment on 8 March 1966, announcing the deployment of a two battalion brigade—the 1st Australian Task Force (1 ATF)—with armour, aviation, engineers and artillery support; in total 4,500 men. Additional Royal Australian Air Force (RAAF) and Royal Australian Navy elements would also be deployed and with all three services total Australian strength in Vietnam was planned to rise to 6,300. Meanwhile, 1 RAR's attachment to US forces had highlighted the differences between Australian and American operational methods. Whereas the Americans relied on massed firepower and mobility in big-unit search and destroy operations as part of a war of attrition which often resulted in heavy casualties on both sides, the Australians—although not eschewing conventional operations—emphasised deliberate patrolling using dispersed companies supported by artillery, APCs and helicopters to separate the Viet Cong from the population in the villages, while slowly extending government control. Consequently, 1 RAR would be replaced at the end of its tour by 1 ATF which would be allocated its own Tactical Area of Responsibility (TAOR) in Phuoc Tuy Province, thereby allowing the Australians to pursue operations more independently using their own methods.

By 1966 Phuoc Tuy Province was dominated by the Viet Cong. With forces dispersed across South Vietnam to defend against the growing communist insurgency, the ARVN was stretched thin with only limited resources available to counter the increasing penetration of the province. Politically, Phuoc Tuy was controlled by the province chief, a South Vietnamese army officer appointed by the central government, and was divided into five districts, each with a district chief. Although the government controlled Ba Ria and the Vung Tau Special Zone, it only partially controlled the village of Long Dien, the western parts of Dat Do and the villages of Long Hai, Xuyen Moc and Phu My during the day. Only the route from Ba Ria to Vung Tau was secure, and outside this area South Vietnamese forces were likely to be ambushed. Although the predominately Catholic village of Binh Gia opposed communist influence, it was isolated with the Viet Cong cadres controlling the remainder of the province, collecting taxes and subjecting the population to extortion and violent intimidation. The Viet Cong increasingly operated in parallel to the South Vietnamese administration. Part of the larger communist province of Ba Long—which also encompassed Long Khanh and part of Bien Hoa Province—the Ba Long Province People's Committee co-ordinated efforts in the province under the direction of the Central Office for South Vietnam (COSVN), an organisation controlled by North Vietnam. Meanwhile, a network of cells and committees known as the Viet Cong Infrastructure provided support and extended their control into the villages and hamlets. The military forces which supported the political apparatus consisted of main forces, local forces and guerrillas. Also controlled by COSVN, collectively they comprised the People's Liberation Armed Forces. Although purportedly separate from the People's Army of Vietnam (PAVN), the North Vietnamese increasingly provided reinforcements to the Viet Cong main forces, while PAVN units themselves would operate in Phuoc Tuy in later years.



Lieutenant General John Wilton, the Australian Chief of the General Staff, departed for Vietnam soon after the announcement of 1 ATF's deployment, meeting senior South Vietnamese officials and US commanders, including Westmoreland, to finalise arrangements. The southern-most province in III CTZ, Phuoc Tuy had been selected by the Australians because it was an area of significant Viet Cong activity, was located away from the Cambodian border, could be resupplied and, if necessary, evacuated by sea, and enabled them to concentrate their efforts in a single area to achieve greater national recognition. Rather than being attached to a US division, negotiations between Wilton and Westmoreland ensured the force would be an independent command under the operational control of US II Field Force, Vietnam (II FFV), a corps-level headquarters based in Bien Hoa which reported directly to Commander US MACV. This would allow 1 ATF greater freedom of action and the chance to demonstrate the Australian Army's evolving operational concept for counter-insurgency warfare which had been developed, at least in part, from its experiences during the Malayan Emergency. The task force would be commanded by Brigadier David Jackson, an experienced infantry officer who had served in the Middle East and New Guinea during the Second World War, and later in Korea, and commanded the AATTV and Australian Army Force Vietnam prior to taking up the appointment. With the new force given less than two months to deploy hasty preparations began in Australia to ready it.

Meanwhile, 1 RAR continued to operate alongside American forces. Over the period 9–22 March it was involved in Operation Silver City, a two-brigade search and destroy mission 25 km north of Bien Hoa in War Zone D under the command of the US 1st Division. In late-March two brigades of the US 1st Division, reinforced by the US 173rd Airborne Brigade and a number of South Vietnamese units, conducted Operation Abilene, a search and destroy mission through Phuoc Tuy Province, targeting the 274th and 275th Regiments of the Viet Cong 5th Division, and their base areas in the May Tao Secret Zone. 1 RAR was tasked with defending a fire support and logistic base established in the Courtenay rubber plantation and later conducted a cordon and search of the village of Binh Ba. Yet the Viet Cong largely avoided battle and contact with the sweeping American brigades was light. On the morning of 11 April the US 2/16th Infantry Battalion clashed with the Viet Cong D800 Battalion at Cam My in fierce close-quarters fighting during the only major action. With both sides too close for American firepower to be effective, casualties were heavy. Viet Cong losses included 41 confirmed dead and possibly another 50, while 35 Americans were killed. In preparation for the arrival of 1 ATF, the population of the fortified Viet Cong village of Long Tan was forcibly removed, with the 1,000 inhabitants resettled nearby and the village destroyed by South Vietnamese forces. The Australians defending the divisional fire support base were also heavily engaged, with the fighting resulting in 14 Viet Cong killed, 12 wounded and 33 captured, while 1 RAR lost four wounded.

Terrain
Located 40 km south-east of Saigon, Phuoc Tuy Province lay on the coast between the mountains of southern central Vietnam and the alluvial plains of the Mekong Delta, dominating the approaches to Vung Tau and the main highway to the capital. Approximately 60 km from east to west and 35 km from north to south, it was roughly rectangular. Mostly flat, it gradually sloped north, while rocky hills rose in the south-west, north-east and south, including the Nui Thi Vai, May Tao and Long Hai mountains. The province was bounded to the north by Bien Hoa, Long Khanh, and Binh Tuy provinces, and to the south-east by the South China Sea. Administratively separate, the Vung Tau peninsula projected south, with the city of Vung Tau at its tip including a shallow water port of strategic importance due to its capacity to relieve congestion at ports on the Saigon River. Phuoc Tuy was bisected by Route 2 running north to the provincial capital of Ba Ria, while Route 15 ran south-west between Vung Tau and Saigon and served as the main supply route for the movement of stores landed at the port, and Route 23 ran east from Baria. With just a quarter of the province used for agriculture, it supported a modest population of 104,636, most of which was concentrated in the south-west in approximately 30 villages and 100 hamlets, including major settlements at Ba Ria, Long Dien, Dat Do, Binh Gia and Xuyen Moc. Racially, the majority were Vietnamese, while there were small numbers of Chinese, indigenous Montagnards, Cambodians and French. Two-thirds were Buddhist, while the remainder were Catholic. Most lived in poverty as farmers, fishermen, labourers, merchants or mechanics. Rice growing was the main industry, although fruit and vegetables were also cultivated, and coastal fishing was extensive. Meanwhile, a number of charcoal kilns, sawmills, salt evaporation ponds and rubber plantations also provided employment.

Geographically the province was ideally suited to guerrilla warfare, consisting of flat, open farmland and rice fields with numerous villages and small settlements, a long and mostly uninhabited coastline aside from the port of Vung Tau and the fishing villages of Lang Phuoc Hai and Long Hai, and a region of dense mangrove swamp and waterways in the south-west known as the Rung Sat, both of which aided infiltration. Meanwhile, isolated mountains covered in dense vegetation provided supply routes and base areas. Rainforest, thick scrub and grassland covered almost three-quarters of the province, in places restricting movement of tracked and wheeled vehicles, limiting visibility to close range and providing extensive concealment. In the lowlands the vegetation provided little obstacle to either mounted or dismounted movement, although a number of watercourses and streams were difficult to traverse, particularly during the wet season, with four major rivers flowing north to south, being the Song Hoa, Song Rai, Song Ba Dap and Song Dinh. Phuoc Tuy had a tropical climate, with the monsoon lasting from mid-May to the end of October, which resulted in several hours of heavy rain up to twice a day, while the dry season lasted from October to May. The Viet Cong and their predecessors, the Viet Minh, had dominated Phuoc Tuy since 1945. As a consequence, the local population had a long tradition of resistance to the former French colonial administration, while communist revolutionary elements later challenged repeated attempts by the ARVN to bring the province under control of the central government in Saigon. In contrast, Vung Tau was largely free from Viet Cong activity and a number of large allied military installations had been established there. A popular seaside resort with many bars and nightclubs, it was rumoured to have been used as a rest centre by both allied and Viet Cong soldiers.

Planning
1 ATF was tasked with dominating its TAOR and conducting operations throughout Phuoc Tuy as required, as well as deploying anywhere in III CTZ and neighbouring Bihn Tuy in II CTZ on order. Its principal objective was to secure Route 15 for military movement to ensure allied control of the port at Vung Tau, while politically it sought to extend government authority in Phuoc Tuy. The task force would be based in a rubber plantation at Nui Dat, 8 km north of Ba Ria, while a logistic base would be established in Vung Tau with a direct link forward via road. Situated on Route 2, Nui Dat's central position offered short lines of communication, was close but not adjacent to the main population centres, and would allow 1 ATF to disrupt Viet Cong activity in the area. Astride a major communist transit and resupply route, it was close to a Viet Cong base area yet near enough to Ba Ria to afford security to the provincial capital and facilitate liaison with the local authorities. Australian doctrine emphasised establishing a base and spreading influence outwards to separate the guerrillas from the population. By lodging at Nui Dat they aimed to form a permanent presence between the Viet Cong and the inhabitants. 1 ATF would then focus on destroying Viet Cong forces in the province, while security of the towns and villages remained a South Vietnamese responsibility. Nui Dat would be occupied in three phases. Firstly, the province chief would remove the inhabitants around the base to create a security zone. Secondly, the US 173rd Airborne Brigade would secure the area with 5 RAR, following its deployment. Finally, the main body would move forward after acclimatisation and training at Vung Tau.

The task force began arriving at Vung Tau between April and June 1966. From 17 May to 15 June, US and Australian forces secured the area around Nui Dat during Operation Hardihood, deploying two battalions of the US 173rd Airborne Brigade and an element of 1 RAR. The Viet Cong resisted strongly, with one company of the US 1/503rd Battalion losing 12 killed and 35 wounded during a clash with a company from D445 Battalion on 17 May, while Viet Cong losses included 16 killed. The clearance of the fortified village of Long Phuoc began two days later. Located within the planned security zone, the 3,000 inhabitants were relocated following heavy fighting between two companies from D445 Battalion and the US 1/503rd Battalion and South Vietnamese forces. American losses were once again heavy; however, by 24 May the clearance was complete with Viet Cong losses including 18 confirmed killed and a further 45 estimated killed, while the dwellings, bunkers and tunnels found within Long Phuoc were destroyed. 5 RAR deployed from Vung Tau the same day and was tasked with clearing any Viet Cong found in an area 6000 m east and north-east of Nui Dat. 1 ATF occupied Nui Dat from 5 June, with Jackson flying-in with his tactical headquarters to take command. The fighting concluded on 15 June with Viet Cong losses totaling 17 killed, eight wounded and eight captured, while five Australians were killed and 15 wounded. Among the dead was a National Serviceman accidentally shot on the first day of the operation—the first killed during the war. Total American losses were 23 killed and 160 wounded. 1 RAR returned to Australia in early June 1966, having completed 13 major operations attached to US forces for the loss of 19 killed and 114 wounded.



The plan to operate independently resulted in significant self-protection requirements and 1 ATF's initial priorities were to establish a base and ensure its own security. Meanwhile, Wilton's decision to occupy Nui Dat rather than co-locate 1 ATF with its logistic support at Vung Tau allowed the task force to have a greater impact on the Viet Cong but resulted in additional manpower demands to secure the base. Indeed, the security requirements of an understrength brigade in an area of strong Viet Cong activity utilised up to half the force, limiting its freedom of action. Jackson was uneasy about the possibility of a concentration against Nui Dat, fearing a major military and political setback if they succeeded in attacking 1 ATF soon after its arrival and caused heavy casualties or damage. He subsequently moved to construct fixed defences and secure the supply route to Vung Tau, as well as implementing a high-tempo patrol program utilising infantry supported by armour, artillery and engineers. Although hampered by the monsoon, defensive positions were dug, command posts sandbagged, and living areas built, while claymore mines, concertina wire and other obstacles were laid, and the vegetation cleared out to small arms range. Standing patrols were established outside the base in the evening and clearing patrols sent out before stand-to every morning and evening along the 12 km perimeter. Daily platoon patrols and ambushes were initially conducted out to 4000 m, which was the range of the Viet Cong mortars, but were later extended to 10000 m to counter the threat from artillery.

As part of the occupation of Nui Dat all inhabitants within a 4,000-metre radius had been removed and resettled nearby. A protective security zone was then established, the limit of which was designated Line Alpha, and a free-fire zone declared. Although unusual for allied installations in Vietnam, many of which were located near populated areas, in doing so the Australians hoped to deny the Viet Cong observation of Nui Dat and afford greater security to patrols entering and exiting the area. While adding to the physical security of the base, disrupting a major Viet Cong support area and removing the local population from danger, such measures were unlikely to endear the Australians to those affected and may have been counter-productive. Indeed the resettlement resulted in widespread resentment and it was debatable how much information the inhabitants would provide on Viet Cong movements, potentially creating an opportunity to attack Nui Dat without warning. Meanwhile, the Viet Cong continued to observe the base from the Nui Dinh hills. Movement was heard around the perimeter over the first few nights as they attempted to locate the Australian defences under the cover of darkness and heavy rain. Although no clashes occurred and the reconnaissance soon ceased, they were believed to be finalising preparations for an attack. On 10 June reporting indicated a Viet Cong regiment was moving towards Nui Dat from the north-west and was about 10 km away. The same day three 120 mm mortar rounds landed just outside the perimeter. That night Australian artillery fired on suspected movement along Route 2, although no casualties were found the following day. Further warnings of a four-battalion attack hastened the call-forward of 6 RAR, which arrived from Vung Tau on 14 June. Despite such reports no attack occurred though and the initial reaction to 1 ATF's lodgement proved unexpectedly limited.

Opposing forces
Part of Military Region 1, the principal communist units operating in Phuoc Tuy were main forces from the Viet Cong 5th Division, including the 274th and 275th Regiments. Under the command of Senior Colonel Nguyen The Truyen, the division was headquartered in the May Tao Mountains. Operating in Phuoc Tuy, Bien Hoa and Long Khanh it included both South Vietnamese guerrillas and North Vietnamese regulars. As part of the campaign against Saigon it was tasked with isolating the eastern provinces by interdicting the main roads and highways, including national routes 1 and 15 and provincial routes 2 and 23. It this role it proved a major challenge to the ARVN, with the 275th Regiment successfully ambushing a South Vietnamese battalion near Binh Gia on 11 November 1965. The 274th Regiment was the stronger and better trained of the two, operating in the Hat Dich in north-west Phuoc Tuy, it included three battalions—D800, D265 and D308—with a strength of 2,000 men. The 275th Regiment was based in the Mao Taos and mainly operated in the east of the province. Commanded by Senior Captain Nguyen Thoi Bung (aka Ut Thoi), it consisted of three battalions—H421, H422 and H421—with a total of 1,850 men. In support was an artillery battalion equipped with 75 mm recoilless rifles (RCLs), 82 mm mortars and 12.7 mm heavy machine-guns, an engineer battalion, a signals battalion and a sapper reconnaissance battalion, as well as medical and logistic units. Local forces included D445 Provincial Mobile Battalion, which normally operated in the south of the province and in Long Khanh. Under the command of Bui Quang Chanh (alias Sau Chanh) it consisted of three rifle companies—C1, C2, C3—and a weapons company, C4; a strength of 550 men. Recruited locally and operating in familiar terrain, they possessed an intimate knowledge of the AO. Guerrilla forces included a further 400 men operating in groups of five to 60, with two companies in Chau Duc district, one in Long Dat and a platoon in Xuyen Moc. In total, Viet Cong strength was around 4,500 men.



South Vietnamese forces included the relatively weak regular ARVN 52nd Ranger Battalion, as well as territorial forces consisting of 17 Regional Force (RF) companies and 47 Popular Force (PF) platoons; in total some 4,500 men. Making up the bulk of government units in Phuoc Tuy, the territorial forces suffered from varying standards of training and motivation. Although most villages were garrisoned by an RF company operating from a fortified compound, and PF platoons guarded most hamlets and important infrastructure, their value was questionable. RF companies were technically available for operations throughout the province, while PF platoons were mostly restricted to operating around their village, yet both were primarily defensive. Although there were examples of RF and PF units successfully defending themselves, they rarely conducted offensive operations; even when they did these were usually limited and lacked initiative or aggression. Mostly recruited from the same population as their opponents, they were subject to the same motivations and pressures, and often suffered equally at the hands of the Viet Cong cadre and the largely inept government. Poorly trained and unable to rely on being reinforced, the territorial forces usually provided little opposition to the Viet Cong. The 90-man US Advisory Team 89 operated in support, as did a small number of Australians from the AATTV. Yet despite their efforts the capabilities of the government forces remained limited. Meanwhile, the arrival of 1 ATF further restricted the ability of South Vietnamese units to carry out operations in Phuoc Tuy as the Australians came to dominate the province.

1 ATF consisted of two infantry battalions—5 RAR commanded by Lieutenant Colonel John Warr, and 6 RAR under Lieutenant Colonel Colin Townsend. Other units included the 1st APC Squadron operating M113 armoured personnel carriers, 1st Field Regiment, Royal Australian Artillery which included two Australian and one New Zealand battery equipped with eighteen 105 mm L5 Pack Howitzers as well as six 155 mm M109 self-propelled howitzers from A Battery, US 2/35th Artillery Battalion which was permanently attached at Nui Dat, 3rd SAS Squadron, the 1st Field Squadron and 21st Engineer Support Troop, 103rd Signals Squadron, 161st Reconnaissance Flight operating Cessna 180s and Bell H-13 Sioux light observation helicopters, and an intelligence detachment. Support arrangements were provided by the 1st Australian Logistics Support Group (1 ALSG) established 30 km south at Vung Tau, while eight UH-1B Iroquois helicopters from No. 9 Squadron RAAF also operated from Vung Tau. US forces also provided considerable support including medium and heavy artillery, close air support, helicopter gunships, and additional utility and medium and heavy lift helicopters. The largest Australian force deployed since the Second World War, although many of 1 ATF's officers and non-commissioned personnel had extensive operational service, it had been rapidly assembled and included many untried National Servicemen. Few men had direct experience of counter-insurgency operations, and even less a first-hand understanding of the situation in Vietnam, while the task force was unable to train together before departure. Yet despite these shortfalls 1 ATF had been required to rapidly deploy and commence operations in a complex environment.

Preliminary operations
With 1 ATF established at Nui Dat subsequent operations included a series of search and destroy missions to gain control over Phuoc Tuy. As the task force sought to extend its influence beyond Line Alpha, in early July 5 RAR patrolled north through Nui Nghe while 6 RAR cleared Long Phuoc to the south, removing a number of former inhabitants who had returned since May. 5 RAR then began operations along Route 2, conducting a cordon and search of Duc My on 19–20 July in preparation for the clearance of Binh Ba. Meanwhile, the SAS conducted long range patrols to the edge of the TAOR to provide early warning of Viet Cong concentrations. Despite such measures the Viet Cong eluded 1 ATF, with the 274th and 275th Regiments believed to be in the north-west and north-east of the province. Yet with the 5th Division assessed as able to concentrate its total strength anywhere in Phuoc Tuy within 24 to 48 hours, it remained a significant threat. As 1 ATF began to have an impact on the Viet Cong's freedom of action a response was increasingly expected. Small-scale probes on the perimeter at Nui Dat and mortar fire had been anticipated and both had since occurred, with such activity a possible prelude to an attack. Regardless, intelligence assessments of Viet Cong intentions changed from those of May and June. Whereas previously a full-scale assault against Nui Dat was expected, as the defences were strengthened an attack against an isolated company or battalion was considered more likely. Other possibilities included continued skirmishes as part of routine patrolling and ambushing, or an attempt to interdict a resupply convoy from Vung Tau.

By the end of July a large Viet Cong force had been detected by SAS patrols east of Nui Dat, near the abandoned village of Long Tan. In response, 6 RAR launched a battalion search and destroy operation and during a series of fire-fights on 25 July a company from D445 Battalion bounced off C Company, and in the process of retreating assaulted B Company which was occupying a blocking position, before being driven off with heavy casualties. In the following days further clashes occurred around Long Tan, resulting in 13 Viet Cong killed and 19 wounded, and Australian losses of three killed and 19 wounded. Yet with the former inhabitants resettled, the village fortified, and the perimeter regularly patrolled, the Australians considered the area secure. However, with the 274th and 275th Regiments still at large, uncertainty resulted in growing tension among 1 ATF. Meanwhile, believing Viet Cong sympathisers had returned to Long Tan, they planned to search the area again on 29 July. That afternoon, as 6 RAR commenced a detailed search following its initial sweep, Jackson ordered its immediate return to Nui Dat in response to South Vietnamese reports of a large Viet Cong presence close to the base, and the battalion was airlifted out by early evening. Although the reports were unconfirmed and an attack against Nui Dat was considered unlikely, 1 ATF was re-postured in response. A number of company patrols were sent out in each direction over the following days, but little of significance was found. Jackson had seemed to over-react, and his requests for assistance from US II FFV were denied. Further intelligence later discredited the original reporting and the crisis soon subsided. Regardless, it was indicative of the alarms 1 ATF experienced during the first months of its lodgement and the effects they caused.

In early August 5 RAR continued operations along Route 2, including the cordon and search of Binh Ba which had been postponed in late July. The clearance of Binh Ba was key to opening the north of the province and linking Ba Ria to Xuan Loc in Long Khanh, yet it was dominated by the Viet Cong, and with a population of 2,100 the operation would be complex. 5 RAR sealed off Binh Ba before first light on 9 August, supported by two companies from 6 RAR, as well as APCs, engineers and artillery. Accompanied by South Vietnamese police, they methodically searched the village while the inhabitants were provided with food and medical aid, followed by further searches of Duc My and Duc Trung. By 10 August Binh Ba and its approaches had been cleared and the Australians commenced searching the areas east and west of Route 2. Although little contact occurred, on 14 August a group of Viet Cong approached an Australian harbour, killing one during a brief fire-fight. Regardless, Route 2 was opened to civilian traffic on 18 August. By the conclusion of the operation South Vietnamese authorities had apprehended 17 Viet Cong and detained a further 77 suspects, eliminating the Binh Ba guerrilla platoon, crippling the infrastructure of the insurgency and bringing the village under government influence, with a South Vietnamese commando company later stationed there to maintain control. Achieved at little cost, it was believed a significant success. Warr considered cordon and search operations vital to the pacification of Phuoc Tuy, arguing they were the only way to neutralise the communist support network and were an essential first step in defeating the Viet Cong main forces even if their effectiveness relied on the questionable ability of the government to rapidly establish competent administration and security.



After two months 1 ATF had moved beyond the initial requirements of establishing itself and securing its immediate approaches, commencing operations to open the province. The Australians had penetrated the Viet Cong base areas to the east and come off the better during a number of clashes with companies from D445 Battalion. Further operations had been conducted in the Nui Dinh hills to west, while road operations along routes 15 and 23 demonstrated their viability, Binh Ba had been cleared of Viet Cong influence and Route 2 opened to civilian traffic. Yet the ongoing need to secure Nui Dat reduced the combat power available to the task force commander, and it was evident that with only two battalions—rather than the usual three—1 ATF lacked operational flexibility, as while one battalion carried out operations the other was required to secure the base and provide a ready reaction force. Significant logistic problems also plagued the task force as 1 ALSG struggled to become operational amid the sand dunes at Vung Tau, resulting in shortages of vital equipment. By the middle of August the Australian troops were growing tired from constant day and night patrolling with no respite from base defence duties. A program of rest and recreation began, with many granted two days leave in Vung Tau, but this further stretched the limited forces available to 1 ATF. Meanwhile, in response to the growing threat posed by the Australians the commander of the Viet Cong 5th Division finally ordered the 275th Regiment to move against Nui Dat.

For several weeks Australian signals intelligence (SIGINT) had tracked a radio transmitter from the headquarters of the 275th Regiment moving westwards to a position just north of Long Tan using radio direction finding; however, extensive patrolling failed to find the unit. Provided by the top secret 547 Signals Troop, the reports began on 29 July at the height of the false alarm, with the radio detected moving towards Nui Dat from a position north of Xuyen Moc. It continued at a rate of 1 km a day and by 13 August had been tracked to a position near the Nui Dat 2 feature, a hill in the vicinity of Long Tan, 5000 m east of Nui Dat. Although direction finding only indicated the movement of the radio, and no transmissions had been intercepted, it suggested the presence of the 275th Regiment, or at least a reconnaissance party of that unit. While deception could not be ruled out, Jackson took the threat seriously and a number of company patrols were sent out. Yet the existence of a SIGINT capability was a closely guarded secret, and knowledge of the source of the reports had been limited to Jackson, his two intelligence officers, and the 1 ATF operations officer, while neither battalion commander had access to such intelligence. On 15 August D Company, 6 RAR patrolled to the Nui Dat 2 feature and returned through the Long Tan rubber plantation. The following day A Company, 6 RAR departed on a three-day patrol on a route which included Nui Dat 2 and the ridge to the north-west. Any sizeable Viet Cong force in the vicinity would have been located, but neither patrol found anything of significance. Meanwhile, SAS patrols focused on the Nui Dinh hills to the west.



By 16 August the communist force was prepositioned east of the rubber plantation at Long Tan, just outside the range of the artillery at Nui Dat. The operation was thought to have been planned by Colonel Nguyen Thanh Hong, a staff officer from the Viet Cong 5th Division who was likely in overall control. Although their intentions have been debated in the years following the battle the aim was likely both a political and military victory, resolving to prove their strength to the local population and undermine Australian public support for the war. The Viet Cong would probably have known one of 1 ATF's battalions was involved in the search of Binh Ba and may have considered Nui Dat weakly defended as a result. Undetected, the force likely consisted of three battalions of the 275th Regiment with approximately 1,400 men, possibly reinforced by at least one regular North Vietnamese Army battalion, and D445 Battalion with up to 350 men. Well armed, they were equipped with AK 47 and SKS assault rifles, RPG-2 rocket propelled grenades, light machine-guns, mortars and RCLs. Large quantities of ammunition were also carried, with each man issued two or three grenades, and grenadiers as many as 10 or 12, as well as a reserve of small arms ammunition, mortar bombs and additional rounds for the crew-served weapons. Meanwhile, the 274th Regiment was probably located 15 to 20 km north-west, occupying a position on Route 2 to ambush a squadron of the US 11th Armored Cavalry Regiment which they anticipated would move down the inter-provincial highway from Long Khanh to support the Australians.

Opening moves, 16/17 August 1966
At 02:43 on the night of 16/17 August Nui Dat was heavily bombarded by the Viet Cong, and was hit by over 100 rounds from several 82 mm mortars, 75 mm RCLs and an old Japanese 70 mm howitzer fired from a position 2000 m to the east. Most of the infantry were deployed at the time, with 5 RAR still engaged on Operation Holsworthy, although a small stay behind party remained. A Company, 6 RAR was still on patrol in the north-east of the TAOR, while a platoon from C Company was manning a night ambush to the south-east. Continuing for 22 minutes, it damaged a number of vehicles and tents and wounded 24 men, one of whom later died. The impact was spread over the south and south-east, with the 103rd Field Battery heaviest hit. Despite coming under fire, the guns from the 1st Field Regiment, RAA were quickly brought into action, commencing a counter-battery mission at 02:50. Yet with the artillery locating radar suspected of being faulty this had to be done using compass bearings on sound and flash. After plotting the likely firing point, a regimental fire mission of 10 rounds was fired from each gun totalling 240 rounds, and the mortaring ceased. With the attack over the Australians remained alert in case of a ground assault; however, no follow up occurred. Regardless, the artillery continued to shell suspected firing positions and withdrawal routes until 04:10. Although the Viet Cong were expected to have withdrawn, a number of company patrols would be dispatched the following morning to search the area east of Nui Dat in response.

Townsend ordered B Company under Major Noel Ford to prepare for a patrol to locate the firing points which were believed to be within an area between the abandoned villages of Long Tan and Long Phuoc, and the Nui Dat 2 feature. Having done so, the patrol was to establish the direction of the Viet Cong withdrawal. Meanwhile, C Company was to provide a platoon mounted in APCs to investigate a suspected base plate location south-west of Nui Dat. A Company would also continue its patrol in the vicinity of Nui Dat 2, while 7 Platoon, C Company—already conducting a night ambush on the southern edge of the TAOR—would search a number of sites as it returned that morning. No SAS patrols were deployed as a result of the overnight attack, although several had previously been planned to the north between Binh Ba and the Courtenay plantation in preparation for upcoming operations, and the program remained unchanged. Another patrol was scheduled near the Song Rai, 16 km north-east of Nui Dat, and it also went ahead. Soon after insertion on the morning of 17 August it noted signs of significant activity, locating several trails moving west made approximately six hours earlier, possibly by a Viet Cong logistic unit. Yet the patrol was compromised and due to radio interference and faulty equipment the information was unable to be reported until its extraction two days later. Regardless, Australian intelligence continued to assess a ground attack against Nui Dat as unlikely. But with the bombardment a likely indicator of further offensive action against 1 ATF, Jackson felt he would be unable to adequately respond with only one battalion. 5 RAR was ordered to return to Nui Dat as a result and was expected back by 18 August.

Although SIGINT had earlier alerted Jackson to the possible presence of a strong Viet Cong force in the vicinity of the Nui Dat 2 feature, patrols of the area revealed nothing and as a consequence B Company did not expect to meet significant opposition. Stepping off early on 17 August they believed they would not be staying out long and were only lightly equipped in patrol order, lacking sleeping gear and rations. With just 80 men—including many due to commence leave in Vung Tau the following day—they were significantly under-strength. Crossing the swollen Suoi Da Bang creek, they soon located the firing point of the mortars as well as signs of their withdrawal as they pushed further east. Meanwhile, A Company, 6 RAR under Captain Charles Mollison, continued its patrol north of the Nui Dat 2 feature, and was involved in three minor clashes with small groups of Viet Cong, killing one and wounding two. B Company was subsequently tasked to remain in the area to search to the north and east the following day and was met by porters that afternoon to supply them with rations. 9 Platoon, C Company returned to Nui Dat with nothing to report, leaving A and B Companies to harbour in their night locations. Speculation about the size of the communist units in the area increased. Captain Bryan Wickens, the 6 RAR Intelligence Officer, assessed that the Viet Cong's use of medium mortars, RCLs and artillery likely indicated the presence of a significant force. Due to growing uncertainty about Viet Cong intentions Jackson agreed that the patrol scheduled for 18 August should be increased from a platoon to company size. D Company, 6 RAR under the command of Major Harry Smith had previously been detailed for a three-day patrol south-east of Nui Dat and was instead ordered to relieve B Company the next day to continue the search. Despite this neither Townsend nor Smith were warned of the possible presence of the 275th Regiment.

Patrolling east of Nui Dat, 18 August 1966
After unexpectedly spending the night in the bush, the following morning B Company released the men scheduled to go on leave to return to Nui Dat. At 07:05 the depleted company, by then reduced to a single platoon and Company Headquarters, continued the search east as far as the edge of the rubber plantation, while A Company searched down the Suoi Da Bang towards their position. A number of weapon pits were subsequently located, as were the firing positions of the mortars and RCLs, while discarded clothing and bloodstains found nearby confirmed the accuracy of the Australian and New Zealand artillery. At Nui Dat D Company, 6 RAR began preparations for its patrol, test firing weapons and packing equipment. Despite the earlier bombardment only the standard ammunition load would be carried. Lightly armed, the Australian riflemen carried just 60 rounds for their L1A1 Self-Loading Rifles and M16 rifles, and 200 rounds for each M60 machine-gun. Smith was briefed by Wickens who highlighted the likely presence of a Viet Cong force equipped with mortars, assessing that it would be incapable of mounting an ambush due to the effect of the earlier counter-battery fire. While the size of the force was unknown it was not considered to be small and the possibility it was part of a larger force preparing to move against Nui Dat could not be discounted. The Viet Cong were believed to be able to attack a company-sized force and to launch mortar attacks similar to that the previous morning. Smith then discussed the patrol with Townsend. If B Company had located the withdrawal route used by the mortar crews, he was to follow it with the aim of interdiction; otherwise he was to continue the search until the track was located. Assuming D445 Battalion to be the only Viet Cong unit in the area from the information available, Smith believed they were looking for that unit's heavy weapons platoon of approximately 30 to 40 men. He briefed his platoon commanders accordingly, although he also felt the Viet Cong would have long since left the area. Meanwhile, 5 RAR (minus one company) returned to Nui Dat.

D Company, 6 RAR departed Nui Dat at 11:00 on 18 August. Led by Smith and accompanied by a three-man New Zealand forward observer party under Captain Morrie Stanley, the 108-man company set-off quickly. Already behind schedule and with B Company having been out for longer than expected, Smith wanted to relieve Ford before more time elapsed and then follow the Viet Cong tracks to continue the pursuit that afternoon. Opting for speed, he adopted single file, with 12 Platoon under Second Lieutenant David Sabben in the lead. Despite the heat the company moved at a fast pace, traversing the low scrub, swamp and paddy fields as they closed in on B Company's position. Meanwhile, the rock and roll acts Little Pattie and Col Joye and the Joy Boys had flown into Nui Dat and were setting up for the afternoon's concert. Many of the Australians were disappointed at the prospect of missing the entertainment, and as they patrolled east they could occasionally hear the music through the trees. At 13:00 that afternoon D Company married up with B Company on the edge of the Long Tan rubber plantation, approximately 2500 m from Nui Dat. D Company moved into a position of all round defence and sentries were posted. While the soldiers had lunch, Smith and Ford took a small protection party and inspected the area. The position appeared to have been used by the Viet Cong as a staging area prior to the bombardment two nights before, while signs of casualties having been loaded into carts and evacuated were also located. Blood stains were also uncovered, as was a quantity of equipment and sandals. The mortar and RCL firing locations were also examined. After briefing Smith, Ford and the remainder of B Company returned to Nui Dat. D Company subsequently took over the pursuit. Smith had noted signs of a fresh track leading north-east; deciding to follow it, he called his platoon commanders in for orders.

Setting off into the rubber plantation at 15:00, D Company paralleled a well-defined track which followed a slightly uphill course, with one platoon forward and two back. 11 Platoon—under Second Lieutenant Gordon Sharp—was in the lead, followed by Company Headquarters, with 10 Platoon on the left under Second Lieutenant Geoff Kendall, and 12 Platoon on the right. Each platoon moved in open formation, with two sections forward in arrowhead and one back on a frontage of approximately 160 m. Moving deeper into the plantation, the older trees and patchy undergrowth gave way to clean straight rows of trees which afforded long views in one direction, but limited visibility in other directions. After 200 m the track divided into two, both of which roughly ran east-south-east in parallel, 300 m apart. At the track junction D Company found evidence of the Viet Cong mortars having been prepared for firing, while further equipment was found scattered which again indicated a rapid withdrawal and the accuracy of the counter-battery fire. Unable to cover both tracks, Smith radioed Townsend. After discussing the situation it was decided D Company would take the more easterly track, towards the limit of the range of their covering artillery. Considering the terrain, Smith adopted a "two up, one back" formation, with 10 Platoon on the left and 11 Platoon on the higher ground on the right. Company Headquarters would be central with 12 Platoon following to the rear. Well dispersed with about 10 m between each soldier, the company had a total frontage of 400 m and was about the same in depth. Amid the rubber observation was between 150 to 200 m, allowing visual contact between Smith and his platoons. This spacing was standard for the Australians in such terrain, yet was larger than that usually adopted by ARVN and US units.

Initial contact
D Company set off again. Shortly afterwards 11 Platoon's lead section crossed a dirt road running south-west to north-east. Straight, well-established and sunken with a clearing on either side, it was 20 to 30 m wide and required the Australians to complete an obstacle-crossing drill as they traversed it. At 15:40, just as the forward sections entered the tree line on the other side but before platoon headquarters could follow, a group of six to eight Viet Cong approached their right flank along the track from the south. Unaware of their presence, the Viet Cong squad continued into the middle of the now divided platoon. One was soon wounded in a brief action after the platoon sergeant, Sergeant Bob Buick, engaged them, while the remainder scattered. They withdrew rapidly south-east, and although the Australians believed it to be just another fleeting contact, artillery was called-in onto their likely withdrawal route 500 m south. After pausing to reorganise, 11 Platoon moved into extended line, sweeping the area on a broad front in pursuit. The Australians recovered an AK 47 and the body of a Viet Cong soldier killed in the contact. Sharp reported to Smith that the Viet Cong had been dressed in khaki uniforms and pith helmets and were carrying automatic weapons, yet soldiers from D445 Battalion typically wore black and were equipped with bolt action rifles or carbines of US origin. At the time only main force units were equipped in such a manner, but the significance of this was not immediately apparent to the Australians as they attempted to follow up. With the area clear following the initial contact, Smith ordered D Company to continue their advance. Meanwhile, Second Lieutenant David Harris was at Headquarters 1 ATF at Nui Dat when the first reports came in. As Jackson's aide he was aware of the intelligence being received and was convinced D Company had clashed with a main force regiment. Harris alerted Jackson, before telephoning Major Bob Hagerty—officer commanding 1st APC Squadron—to warn him of the possible requirement for his standby troop.



Moving forward again, D Company continued east. 11 Platoon's rapid follow-up had opened a 500 m gap with Company Headquarters, while the two lead platoons were now also widely dispersed. 11 Platoon penetrated further into the plantation, widening the gap with 10 Platoon, and they were now more than 300 m apart. Although 12 Platoon in the rear covered most of the ground bypassed by the forward platoons, the gap was such that their flanking sections had lost sight of each other, while Smith was unable to see them either in the dense vegetation. At that distance the spacing between the Australians was now greater than the maximum effective range of their rifles and machine-guns. Meanwhile, 11 Platoon had moved forward approximately 250 m from the first engagement. As Smith reached the site of the initial contact the sound of firing continued to the front as Sharp manoeuvred his sections in pursuit of the withdrawing force. Still in extended line, 11 Platoon came across a rubber tapper's hut, and believing sounds emanating from the building were from Viet Cong hiding there, Sharp launched a platoon attack. Yet the Viet Cong had fled prior to the attack, and the assaulting sections swept through the area finding only two grenades. Advancing with three sections abreast—6 Section on the left, 4 Section in the centre and 5 Section on the right—the Australians pushed on through the rubber towards a clearing. This formation allowed them to cover a broad front but offered little flank security.

At 16:08, shortly after resuming the advance, 11 Platoon's left flank was engaged by machine-gun fire from an undetected Viet Cong force, killing and wounding several men from 6 Section. Thy went to ground and adopted firing positions, only to be engaged by a second machine-gun firing tracer. The initial firing lasted two to three minutes then stopped, and Sharp then ordered 5 Section to sweep across the front of the platoon from the right. Yet just as they began to move, the Australians came under heavy small-arms fire and rocket propelled grenades from their front and both flanks. Pinned down by the weight of fire, and under threat of being overrun, the isolated platoon was forced to fight for their lives. Over the next 10 to 15 minutes the Viet Cong engaged 11 Platoon with devastating fire, which put their left flank out of action. At that moment a heavy monsoon rain began which reduced visibility to just 50 m and turned the ground to mud. Assessing the Viet Cong to be in greater strength than previously thought and believing they were preparing for an assault on his position, Sharp called for artillery fire as he moved to bring his exposed section back into line and then gradually draw his platoon into all-round defence. He reported that he was under fire from a force estimated to be platoon-sized. The Australians started the contact believing they were the numerically superior force and would attack the Viet Cong, yet far from clashing with a small force which would attempt to withdraw before being decisively engaged, 11 Platoon had run into the forward troops of a main force regiment. Beginning as an encounter battle, heavy fighting ensued as the advancing battalions of the 275th Regiment and D445 Battalion clashed with D Company, 6 RAR and attempted to encircle and destroy them.

11 Platoon is isolated
Amid the noise of machine-gun and rifle fire and the Viet Cong bugle calls, Stanley quickly brought the 161st Battery, Royal New Zealand Artillery into action in an attempt to support the Australian infantry. Yet as he was unable to see them, for safety reasons the initial rounds were directed a distance from 11 Platoon's known location, before "walking" the fire in to between 200 to 300 m from their position, aided by D Company's favourable location between the Viet Cong and the gun position at Nui Dat, which allowed the rounds to pass over their heads and fall away from them. Falling beyond 11 Platoon, the rounds exploded amid the Viet Cong as they began to form up for an assault. But with 11 Platoon engaged from its left, front and right, it became clear the Viet Cong force was stronger than a platoon, and was probably at least company-sized. Supported by heavy machine-guns, they launched a series of assaults against 11 Platoon, only to be held off by small arms and artillery fire. As the fighting continued Stanley realised that a single artillery battery would be insufficient, and at 16:19 he requested a regimental fire mission, using all 24 guns of the 1st Field Regiment, RAA. The Viet Cong continued their assault regardless, surging around the flanks of 11 Platoon. The Australians responded with controlled small arms fire, picking off a number of Viet Cong soldiers as the rain and artillery continued to fall around them. After making the required corrections Stanley requested another regimental fire mission at 16:22, yet still unable to see the rounds land he had to work entirely from radio communications with 11 Platoon, adjusting the fire over an area of 200 m using just a map.



Less than twenty minutes after the initial contact more than a third of 11 Platoon had been killed or wounded. Several 60 mm light mortar rounds were subsequently fired towards the D Company position and although they landed to the east they further separated the remainder of the company from 11 Platoon, putting the main body behind a slight rise. At 16:26 Smith reported to Townsend that D Company was facing a force of company-size and that they were using mortars, urgently called for artillery support. Shortly afterwards Sharp was shot and killed after he raised himself to observe the fall of shot. With the platoon commander dead, Buick took charge of 11 Platoon, directing the artillery through Stanley. Unable to extricate itself, 11 Platoon was almost surrounded as the Viet Cong continued to assault their position. Suffering heavy casualties and running short of ammunition, Buick desperately radioed for assistance. Soon after the aerial of the platoon's radio was shot away and communications were lost. Meanwhile, Smith requested aerial fire support from armed CH-47 Chinooks or an air-strike to deal with the mortars. In response, Stanley organised counter-battery fire from the American 155 mm self-propelled howitzers at Nui Dat, which appeared to silence them. These mortars were not the 82 mm variants that had bombarded Nui Dat on 16/17 August and although no further mortar fire was reported at the time, they may have fired at B Company later in the battle.

Meanwhile, 10 Platoon was approximately 200 m to the north and Smith ordered it to move up on the left of 11 Platoon to try to relieve pressure on them and allow a withdrawal back to the company defensive position. Dropping their packs, Kendall's platoon wheeled to the south-east in extended line, advancing towards 11 Platoon. As they came over a small rise, through the rain they observed a regular Viet Cong platoon of 30 to 40 men advancing south, firing on 11 Platoon as they attempted to outflank them. Advancing to close range before dropping to their knees to adopt firing positions, 10 Platoon engaged them from the rear, hitting a large number and breaking up the attack. As the surviving Viet Cong withdrew, Kendall pushed on. Yet shortly after 10 Platoon was also heavily engaged on three sides from a heavy machine-gun firing tracer from the high ground of the Nui Dat 2 feature 400 m to their left, wounding the signaller and damaging the radio and putting it out of action. Now also without communications, and still 100 to 150 m from 11 Platoon, 10 Platoon moved into a defensive position, fighting hard to hold on. Finally a runner arrived from Company Headquarters with a replacement radio, having moved 200 to 300 m through heavy fire as he attempted to locate the platoon, killing two Viet Cong with his Owen gun on the way. With the wounded starting to arrive back at Smith's position and communications with 10 Platoon restored, he ordered Kendall to pull back under cover of the artillery. 10 Platoon was ultimately forced back to its start point.

Reaction at Nui Dat
It appeared the Viet Cong would shortly overrun D Company if they were not soon reinforced. Yet, with 1 ATF lacking sufficient forces to maintain a dedicated reserve at Nui Dat, no suitable quick reaction force was prepared to deploy at short notice. Consequently it would take several hours to organise a relief force. Although essentially a sub-unit battle fought by a rifle company supported by artillery and co-ordinated by Townsend from the 6 RAR command post at Nui Dat, Jackson was concerned. Not only was D Company in trouble, but the entire force might be under threat, while the additional resources available to the task force might be required. As a result he remained in constant contact with Townsend, although ultimate control remained with the latter. Viet Cong jamming on the Battalion Command net forced them to switch frequencies to communicate with D Company, while with such a capability rarely found below divisional-level, they were likely more heavily outnumbered than first thought. At 16:30 Townsend issued a warning order to A Company to prepare to reinforce them, despite themselves only having returned from a three-day patrol an hour prior. Intending to lead the company out himself and take command of the battle, 3 Troop, 1st APC Squadron under Lieutenant Adrian Roberts was also warned to be ready to lift the relief force. American ground attack aircraft at Bien Hoa were also placed on alert by Headquarters 1 ATF. Meanwhile, on hearing the sounds of the fighting while returning to Nui Dat, B Company halted 2300 m short of the base and was ordered to rejoin D Company. Apparently under close observation from the Viet Cong, they were engaged by two 60 mm mortars as they turned around, but suffered no casualties.

Requiring the task force commander's permission to send out the relief force and to accompany it, Townsend telephoned Jackson. Jackson was concerned for the safety of the entire force and was initially reluctant to authorise the dispatch of the relief force should it weaken the position at Nui Dat. He was unsure of the size of the Viet Cong facing D Company, although from Smith's reports it appeared to be at least a regular battalion. Meanwhile, intelligence suggested it was likely part of the 275th Regiment, although the locations of the remaining two battalions of the regiment were unknown, as were those of D445 Battalion. The location of the 274th Regiment was equally unclear. Although radio direction finding suggested it may have been near Phuoc Tuy's northern border, three weeks earlier it had been reported close to the western side of the Australian TAOR, while one of its battalions had incorrectly been believed to be involved in an attack on Phu My in the south-west of the province on 11 August. Consequently, Jackson reasoned that if the battle unfolding near Long Tan was the opening phase of an attack on Nui Dat the main assault was still to come, and he would require the bulk of his forces to defend the task force base. He considered the commitment of A Company would tie up the bulk of 6 RAR and the artillery. Yet Townsend believed Nui Dat's defences to be sufficient to deter such an attack, even if they remained incomplete, while the strategic reserve held by US II FFV could also be enacted if required. Ultimately Jackson gave his in-principle support to the plan; however, he would not release the relief force until he thought it warranted.

Fighting continues
By 16:50 it was apparent to Smith that he was facing a force of at least battalion-strength. Yet with his two forward platoons still separated and unable to support each other, D Company was badly positioned for a defensive battle. 10 Platoon had been prevented from engaging the Viet Cong attacking 11 Platoon, and was unable to support its withdrawal as a result. Meanwhile, 11 Platoon had gone to ground in extended line following the initial contact, leaving its flanks vulnerable, while its aggressive push forward prior to the engagement also complicated the application of artillery support, which had to be switched to support each platoon as required rather than allowing it to be concentrated. Unable to see either platoon, the D Company artillery forward observer was unsure of 11 Platoon's exact position, further delaying the process. As a consequence 10 and 11 Platoons were each forced to fight their own battles, and despite the weight of the indirect fire increasingly becoming available to support the Australian infantry, the Viet Cong were able to apply superior fire power as they tried to isolate and attack each platoon in turn. To retrieve the situation Smith planned to pull his company into an all-round defensive position to enable his platoons to support each other and fight a co-ordinated battle and care for the wounded until a relief force could arrive to assist. Seemingly intent on attacking Nui Dat, the Viet Cong moved to overrun the beleaguered force, but the dispersal of the Australian platoons made it difficult for them to find D Company's flanks and roll them up, and may have led the Viet Cong commander to assess that he was facing a much larger Australian force.



In the meantime Buick succeeded in repairing the 11 Platoon radio, and was able to re-establish communications with Company Headquarters, and with Stanley, who was again able to adjust the artillery by radio. Yet the Viet Cong succeeded in closing to within 50 m of 11 Platoon's position, and much of the artillery was beginning to fall behind them as a result. Although the fire was likely impacting the Viet Cong rear area and was probably causing considerable casualties there, the assault troops had deliberately closed with the Australians to negate its effect. Buick estimated 11 Platoon was being assaulted by at least two companies; down to the last of their ammunition and with just 10 of its 28 men still able to fight, he feared the platoon would soon be overrun and destroyed, and would be unlikely to survive more than the next 10 to 15 minutes. Confident the rest of D Company would be attempting to reach them, but unable to see how that might occur, Buick requested artillery fire onto his own position despite the danger this entailed. Stanley refused, although after confirming 11 Platoon's precarious situation, he was able to walk the artillery in closer. Landing 50 to 100 m to their front, the artillery detonated among a large concentration of Viet Cong troops, destroying an entire assault line as they formed up. Three US F-4 Phantoms arrived on station at 17:00 for an airstrike arranged by Battalion Headquarters.

At 17:02 Smith reported D Company was running low on ammunition and required aerial resupply. With just three magazines carried by each rifleman, the Australians were only lightly equipped prior to the battle. This was a standard load calculated on 1 RAR usage rates which had been enough during previous actions, but it proved insufficient for sustained fighting. Due to the thick vegetation the ammunition boxes would need to be dropped through the trees, and intending on moving his headquarters behind a low knoll, Smith nominated a point 400 m west. This position would afford greater protection, while the helicopters would be less likely to attract ground fire. Yet with their casualties now unable to be moved, D Company would have to remain in location instead. Townsend passed the ammunition demand to Headquarters 1 ATF. In response Jackson requested two UH-1B Iroquois from No. 9 Squadron RAAF to deliver it; however, the senior Air Force officer at Nui Dat, Group Captain Peter Raw, was not prepared to risk aircraft hovering at tree-top height in the heavy rain where they would be exposed to ground fire, citing Department of Air regulations. Relations between the Army and Air Force over the use of the helicopters had become increasingly bitter in the months prior, and were still tenuous despite recent improvements. Jackson requested American assistance, and when the US Army liaison officer responded more favourably, Raw felt no alternative than to accede to the original request, offering RAAF helicopters to effect the resupply instead. By coincidence two Iroquois were available at Nui Dat, having been used as transport for the concert and were committed to support D Company.

Smith requested close air support, calling for the waiting aircraft to drop napalm across 11 Platoon's eastern frontage. The Phantoms were soon overhead; however, due to the rain and low cloud they were unable to observe the coloured smoke thrown by the Australians to mark their position through the trees. Stanley was forced to halt the artillery while the aircraft flew overhead, yet with Smith unable to establish communications with the forward air observer he wanted them out of the area so it could resume firing. Townsend directed the aircraft to drop their payloads on the forward slopes of the Nui Dat 2 feature instead, believing it the location of the Viet Cong command element. With the artillery beginning to fall again and with the Australians still heavily outnumbered it proved critical in preventing them from being overrun as the Viet Cong formed assault waves. Major Harry Honnor—officer commanding 161st Battery, RNZA which was attached to 6 RAR as its direct support battery—served as artillery advisor to Townsend at Nui Dat and during the battle controlled the fires of the three field batteries, as well as directing the American medium artillery against depth targets. On the ground Stanley would either call down the fire himself or would relay the direction of the assault by radio, from which Honnor would select targets and order the fire, which was then adjusted by Stanley using sound ranging to bring it closer. Despite the rain and the soft ground reducing the impact of the shell bursts, the effectiveness of the artillery was aided by the otherwise favourable technical conditions, including the location of the infantry between the guns and the assaulting Viet Cong, the convenient range of 5000 to 6000 m at which the engagement occurred, good communications afforded by the newly issued PRC-25 radios, the air burst effect created by rounds exploding in the rubber trees, and a large supply of rounds which had been stock-piled at Nui Dat.

12 Platoon attempts to link up with Buick
Having been repulsed on the left, Smith tried the right flank. Pushing his headquarters forward, he ordered Sabben to move 12 Platoon—until then held in reserve—up on the right to support 11 Platoon. Yet as new radio traffic was received Smith was again forced to ground to work on fresh orders, while the arrival of an increasing number of casualties required the establishment of an aid post in the dead ground, which effectively tied them in location and prevented further manoeuvre. Meanwhile, at 17:05 Roberts arrived at the 6 RAR headquarters at Nui Dat with his troop of 10 APCs, and was quickly briefed by the Operations Officer on the situation before departing to pick up A Company from their lines. After more than an hour of fighting D Company was still widely dispersed; 10 Platoon had been unable to break through to 11 Platoon from the north, while there remained only a slight chance 12 Platoon would have more success from the north-west. With the Viet Cong enjoying a considerable numerical advantage Smith feared his platoons would be defeated in detail and that it was only a matter of time before his entire company would be overrun, despite the devastating effect of the artillery on the Viet Cong assault formations. 12 Platoon stepped off at 17:15, moving south-east in an attempt to retrieve the now cut-off 11 Platoon, but having been forced to leave 9 Section behind to protect Company Headquarters and support the wounded, with just two sections it was significantly under-strength.

At 17:20 Smith requested an airmobile assault to reinforce his position; however, due to the bad weather, poor visibility, time of day and lack of a suitable landing zone this was considered impossible. Instead, Townsend informed him a relief force consisting of an infantry company mounted in APCs would be dispatched. Yet Jackson was reluctant to reduce the defences at Nui Dat, considering the attack a possible feint. Consequently, although Smith had repeatedly pressed Townsend there had been a delay of more than an hour from when the relief force was ordered to ready themselves to the time Roberts was allowed to move. Townsend finally ordered the relief force to move at 17:30, having received Jackson's approval for their release. A Company, 6 RAR and 3 APC Troop had been on standby in the company lines and departed fifteen minutes later. But with the route largely dictated by the terrain, the possibility of the relief force being ambushed concerned Townsend and Jackson. Regardless, neither saw any alternative given the dire situation and considered it unlikely given the ground had been covered by frequent patrols, the proximity of D Company's position to Nui Dat, the open country between the base and the rubber plantation and the fact it was still daylight, even if the light was rapidly fading. With 5 RAR back at Nui Dat, Jackson ordered it to take over the defensive positions normally occupied by 6 RAR, while deploying a platoon to the 1st APC Squadron lines, and placing D Company, 5 RAR on one hour's notice to move if required. The remainder of the battalion prepared to repel any attack on Nui Dat or to pursue the Viet Cong if they withdrew.



Meanwhile, after having departed D Company's position the two sections from 12 Platoon moved south towards the sound of firing which could be heard approximately 400 m away. Unaware of the exact position of 11 Platoon, Sabben instead located the rubber tapper's hut previously assaulted by Sharp in the opening phases of the battle. However, as they advanced they were forced to fight off an attack on their right flank before eventually pushing forward another 100 m. By this time the Viet Cong had succeeded in pushing behind 11 Platoon in an effort to outflank them, and a large force subsequently clashed with 12 Platoon as they attempted to come to their aid. Advancing from the north, two Viet Cong platoons then assaulted the Australians, who were now heavily engaged from three directions. Meeting a similar fate as 10 Platoon, Sabben's platoon was forced to ground 150 m short of their objective and were themselves in danger of being encircled. Sustaining increasing casualties, they clashed with several groups of Viet Cong moving around their western flank in an attempt to get between 11 and 12 Platoon and form a cut-off force prior to mounting a frontal assault. In so doing 12 Platoon succeeded in opening a path to 11 Platoon, yet after 45 minutes under fire Sabben was now unable to advance any further and with the rain reducing visibility to just 70 m he was unsure of Buick's location.

At 18:00 two RAAF UH-1B Iroquois helicopters piloted by Flight Lieutenants Cliff Dohle and Frank Riley arrived over D Company's location with the ammunition resupply, and guided by red smoke thrown by the infantry, they hovered in the heavy rain just above the rubber trees near a small clearing. Because they were to be dropped from some distance, the wooden outer crates—which were still banded with metal straps—were wrapped in blankets for the wounded. Aboard the helicopters the 6 RAR Regimental Sergeant Major, Warrant Officer George Chinn, and the officer commanding Administration Company, Major Owen O'Brien, pushed the crates out to the soldiers waiting below, many of whom were now very low on ammunition. The boxes landed in the centre of the position and the RAAF pilots were later praised for their skill and daring. Riley was later awarded the Distinguished Flying Cross, while Dohle was mentioned in despatches. Yet, without tools to cut the straps, the infantry had to smash the crates open with machetes and the butts of their rifles to get to the inner metal boxes. Under heavy fire Warrant Officer Jack Kirby, the Company Sergeant Major, and Sergeant Neill Rankin, the 12 Platoon sergeant, began to distribute the ammunition. However, while the machine-gun rounds were pre-loaded in belts, the rifle rounds was still in bandoliers, complicating Kirby's job and forcing the soldiers to reload their own magazines as they struggled to keep the ammunition clean in the mud and rain. Regardless, the resupply retrieved the situation for D Company. Prior to its arrival they had been down to their last 100 rounds, but with the resupply complete the Australians resumed firing, forcing the Viet Cong back for a third time.

D Company regroups
Despite being exposed to heavy fire from three sides 11 Platoon had maintained its position for over two hours, narrowly holding off the Viet Cong with small arms fire and massive artillery support. However, many of the platoon had been killed or wounded, while most of the survivors were now out of ammunition. To their rear Sabben threw yellow smoke in the hope it would be seen through the trees by the beleaguered platoon. Finally, with the close artillery fire causing heavy casualties among the assaulting Viet Cong, Buick decided to take advantage of a temporary lull in the fighting to achieve a clean break. Intending to withdraw 100 to 150 m west to regroup, on his signal the platoon rose to their feet. One of the Australians was immediately shot and killed as he did so, while two more were wounded before they reached a position of temporary safety. From this location Buick could see yellow smoke 75 to 100 m away, and believing it to be Smith's headquarters, 11 Platoon moved towards it calling out to identify themselves as they approached. Locating 12 Platoon instead, but still finding themselves heavily engaged, the two platoons moved back to the company position covered by the artillery and torrential rain. By 18:10 D Company had reformed, while the Viet Cong appeared to have momentarily broken contact. Having concentrated his company, Smith began to re-organise it into a position of all-round defence.

Smith attempted to place his depleted platoons into a position from which they could defend themselves, yet D Company's location had been dictated by the actions of the Viet Cong and the need to care for the wounded, and as a result they had little choice of the ground on which to make their stand. Yet with the Australians occupying a shallow fold in the ground on a reverse slope the terrain proved decisive. Against this position the Viet Cong found it difficult to use their heavy calibre weapons effectively and as a result they could only engage the Australians at close range. Meanwhile, the jungle covered Nui Dat 2 feature lay 1000 m to the north-east, while an impenetrable wall of thick bamboo and scrub abutted the lower slopes to its west, following the northern edge of the rubber plantation 200 m from D Company's position, running north-east to west. In contrast, the remainder of the position faced the relatively open rubber plantation. Believing the northern approach unsuitable for a major assault, Smith assessed the most likely Viet Cong course of action to be a frontal assault from the east, or a flanking attack from either the south or south-west. As a consequence he placed 10 and 12 Platoons in positions on the southern and eastern flanks, while the badly mauled 11 Platoon was allocated a position to the north-west. Company Headquarters was located in the south-west. During the lull Smith walked around the position to gain an understanding of the situation and check the condition of the wounded. With one platoon almost destroyed, and the other two at approximately 75 percent of their original strength, D Company had been battered but their morale remained high. While Smith tied in the position, Kirby completed the distribution of ammunition and Stanley plotted new defensive fire tasks for the artillery.

The respite proved only brief as with Viet Cong soon located the Australian position. At 18:20 they began to re-engage D Company with concentrated machine-gun fire from the east and south-east as they reorganised for a further attack. Movement was soon detected through the trees; however, at a distance of 150 to 200 m the Australians thought they may have been B Company, and only engaged the Viet Cong as they moved out of range to the north. By following up the withdrawal of 12 Platoon and conducting a number of probes the attackers succeeded in confirming D Company's position. A company-sized Viet Cong force subsequently formed up to their south on a broad frontage which threatened to engulf them. Heralded by a number of bugle blasts, the assault commenced at 18:35, marking the beginning of a series of human wave attacks against D Company. Well spaced, the assault force stepped-off at a fast walk supported by a company in reserve which moved 90 m to their rear. Yet as they did so an accurate barrage from the Australian artillery fell among them, effectively destroying the rear echelon. The assault force continued on regardless, only to be engaged with small arms just 50 m from the forward Australian positions. Now lacking any reserve the assault was rapidly halted, although many of the attackers that remained unwounded then attempted to crawl around the D Company perimeter, from where they engaged the Australians in a number of individual duels, while snipers also fired from the trees.

A second assault began soon after, advancing over the same ground only to again be hit heavily by the artillery, with the survivors going to ground among the growing number of dead and wounded. As they moved forward they were joined by some of the survivors of the first assault and together they attempted to roll over the Australians. The Viet Cong then tried to site another heavy machine-gun just 50 m from the D Company perimeter, but Kirby personally moved out and killed the crew. Despite their casualties the heavy attacks continued amid the rain, supported by machine-guns. The main attacks came from the east, south-east and south, falling mainly on 10 and 12 Platoons, while smaller attacks were also carried out around the rest of the perimeter. However, due to the slope of the ground much of the fire passed over the heads of the Australians, protecting many from becoming casualties. The slope also had the effect of screening the advancing Viet Cong, largely preventing them from firing at the Australians until they had moved within 50 metres of their position, while at the same time preventing the Australians from effectively engaging the assault force until they had closed with them. Few survived the heavy artillery fire to get that close though. Meanwhile, the Viet Cong had set up a light and a heavy machine-gun on the forward slopes of the Nui Dat 2 feature and these continued to engage the Australians throughout the battle. Yet, while they were able to achieve plunging fire from their vantage point they were unable to observe D Company's position through the rubber and were reduced to sweeping a broad area. Australian casualties included four killed and several wounded during this period, the majority from head and chest wounds.

A Company and 3 Troop fight through
By 18:45, D Company had succeeded in moving into an all round defensive position, nearly two and a half hours after the battle began. With the Australians concentrated they threw back a heavy attack from the south-east, and then further thrusts from the east, north-east and south in close succession. Yet with D Company unable to manoeuvre the initiative lay with the Viet Cong, and the massed artillery of 1 ATF was required to keep them at bay, with the main role of the infantry increasingly becoming one of protecting their forward observer. Indeed Stanley's efforts remained crucial to the continued survival of D Company and with the platoons now co-located his job became easier. He was able to observe their positions for himself, rather than relying on the reports of the infantry, and subsequently brought the fire to within 25 to 30 m of the forward positions. At least one round landed within the D Company perimeter, wounding one of the defenders; regardless, the close fire continued to devastate the Viet Cong ranks. Despite the firepower available to support it, D Company was still heavily outnumbered, and as they awaited another assault their destruction seemed imminent. The fate of the battle now rested on whether the Australians were strong enough to repel the Viet Cong soldiers that succeeded in penetrating the barrage until a relief force arrived. A simultaneous assault from multiple directions threatened to divide the artillery and might allow a strong thrust to overrun the Australian position. A fresh force was then observed moving to the west, likely in an attempt to encircle and cut-off D Company.



Meanwhile, the progress of the relief force had been slowed by a number of factors including flooding from the heavy rain, Viet Cong action, poor equipment, limited communications and an ambiguous command relationship between the armour and infantry. Although normally having a strength of 13 APCs, 3 Troop had been reduced to just seven on 18 August, with the remainder undergoing maintenance, while many of those available suffered from mechanical problems and obsolete radios. As a consequence they were joined by three vehicles from 2 Troop to make up the numbers, although these lacked gun shields, leaving the crew commander exposed. Mounted in the carriers, 100 men from A Company 6 RAR departed Nui Dat under the command of Mollison, with orders to relieve the pressure on D Company by attacking from the south and then to reinforce them and secure the area to allow the evacuation of the wounded. However, with there being relatively few gaps in the Nui Dat perimeter wide enough for the APCs, Roberts was forced to take a circuitous route south-east through the base. On arrival he found the exit had moved due to road works being carried out by the engineers, and this resulted in further delay until an alternative could be located. At 17:55, after finally clearing the barbed wire, Roberts was ordered to send two carriers back for Townsend and to wait until he came up, as he intended to accompany the carriers rather than move by helicopter. Detaching two carriers, Roberts ignored the second part of the order and the remainder of the troop proceeded, leaving Nui Dat at 18:00.

As the rain began Roberts moved along the edge of the rubber plantation north-east of Long Phuoc in column, descending to the Suoi Da Bang which was now heavily swollen. The terracing of the paddy fields along the creek resulted in a steep drop to the water and a difficult climb out; however, using a bullock track alongside an agricultural dam which he had previously utilised during Operation Hardihood in May, Roberts began to swim the carriers across the creek despite the fast moving current which threatened to wash them downstream. At 18:10 Roberts was ordered for a second time to halt and wait for Townsend. Yet he continued to monitor D Company's situation over the radio and again chose to disregard the order. Mollison concurred, agreeing not to halt and wait for Townsend to catch up, and they proceeded to cross the creek. After completing the dangerous crossing without incident, Roberts left one carrier and its infantry to secure it and to act as a guide for Townsend, while the remaining seven APCs continued to move towards the battle. Advancing another 1 km, the relief force reached the junction of Route 52 and the north-west running road through the rubber plantation by 18:20. The road led directly to the scene of the fighting, and using it as his centre axis, Roberts deployed one section of three APCs on the right under the command of Sergeant Ron Richards and one on the left under Sergeant Leslie O'Reilly, each with two vehicles forward and one back evenly spaced 40 m apart, while he remained in the centre moving astride the road. At 18:22 the formation began to advance on a 300 m frontage, only to again be ordered by radio to halt and wait for Townsend. With sunset due at 19:11 and darkness already beginning to fall due to the heavy rain clouds overhead, Roberts once more decided to press on.

The relief force moved into the plantation in open formation, unaware of the location of D Company or the Viet Cong. With visibility limited by the low vegetation of the young rubber trees and the heavy rain, they suddenly encountered a company moving west in arrowhead dressed in greens, cloth hats and webbing. Initially uncertain of the identity of the men, the Australians briefly paused. Realising they were Viet Cong attempting to outflank D Company to attack it from the rear, Lieutenant Peter Dinham—commander 2 Platoon travelling in the right-hand APC—ordered the crew commander to engage and they were soon joined by the remainder of the troop. The rain had masked their approach and the Viet Cong—later identified as the weapons company from D445 Battalion—were caught by surprise as the cavalry crashed into their flank. Recovering rapidly though, they returned a heavy volume of machine-gun fire, covering their casualties as they were dragged to the rear. Meanwhile, the platoon sergeant had been travelling on top of the overcrowded carrier and was forced to jump clear to avoid being hit. Dinham ordered the rear door open and the section disembarked to protect him. They were soon joined by the remainder of the platoon. Moving into assault formation 2 Platoon advanced, engaging the Viet Cong and causing heavy casualties. The spontaneous assault caught them by surprise, adding to their growing disorder. However, as the fighting continued it further delayed the advance of the relief force, and with Roberts concerned the presence of the infantry forward of his vehicles would prevent the APCs from employing their heavy weapons, he called to Mollison to order them to return to the carriers. After re-embarking the infantry 3 Troop resumed the advance, breaking into the Viet Cong force as it streamed west, firing their .50 calibre machine-guns, while the infantry engaged with small arms from the open hatches. D445 Battalion was routed and forced to withdraw east having lost an estimated 40 killed, while one Australian was wounded.

3 Troop continued forward in assault formation, moving deeper into the plantation. As they did so the young rubber gave way to more mature trees of approximately 10 m high, improving visibility and allowing them to increase their speed. Meanwhile, by 18:30 B Company was also drawing near on foot, and they observed the Viet Cong moving around the western flank, likely in an attempt to escape the APCs. Shortly after they were accidentally engaged by the cavalry themselves and suffered one man wounded. After moving a further 200 m the relief force came out of the tree-line where they were confronted by groups of eight to 10 Viet Cong moving east, in total about 100 men. Believed to be the lead elements of the force that had just been struck, after abandoning its attempt to outflank D Company it was now withdrawing in the opposite direction. The APC crews opened fire, engaging their flank with their heavy machine-guns. A number were hit while others turned to engage the cavalry as it closed with them. A 57 mm RCL then engaged one of the APCs at close range with the round narrowly missing and blowing apart a tree which fell across the vehicle. The crew commander, Corporal John Carter, engaged the anti-armour team from the top of the APC as they reloaded, yet his .50 calibre machine-gun jammed just as they fired again and he killed two of them with his Owen gun from just 15 to 20 m. The second RCL round subsequently detonated against the fallen tree, saving both the vehicle and its occupants. Despite being dazed Carter killed three more Viet Cong soldiers as he scrambled back into the carrier which was now without communications following the destruction of its aerial. By drawing further fire he allowed the remainder of the troop to advance, and for his actions was later awarded the Distinguished Conduct Medal (DCM).

The possible presence of a second RCL team sited in mutual support forced the Australians to halt once again. Concerned about the consequences of bypassing an anti-armour weapon only to be engaged from the rear, Roberts ordered the troop to scan the area. Frustrated by the delay, Mollison demanded Roberts continue the advance, and an argument broke out between the two. However, as the commander of the APCs Roberts ignored Mollison despite his more senior rank, refusing to continue until he either located the weapon or was confident the threat did not exist. Finally, following a five-minute delay the Australians moved off again after no weapon was located. A machine-gun then engaged three of the APCs in the left hand section, none of which had gun shields. One of the crew commanders was fatally wounded and the vehicle forced to a halt, but not before the Viet Cong machine-gunner was crushed to death by the driver. The troop sergeant ran between the carriers under heavy fire to take command of the APC after Roberts ordered him to return to Nui Dat due to the mistaken belief a number of the infantry on board had also been wounded. Despite Mollison's objections the vehicle departed, taking the headquarters of one of the infantry platoons with it. Still uncertain of the location of D Company, Roberts was forced to closely control the fire of the troop due to the concern any survivors might be hit by overshoots from the armoured vehicle's heavy machine-guns. At the same time the infantry continued to engage from the rear of the vehicles. A further 45 Viet Cong were estimated to have been killed during this action.

Relief of D Company
Unaware of the hold up on the left flank, the right hand section of APCs continued to advance. Pressing on, the section crossed a small track and moved through the artillery fire called in by Smith on D445 Battalion as it had attempted to outflank D Company. As they moved closer to D Company the carriers were engaged by small arms and RPGs, one of which exploded near the tracks of one of the advancing carriers, albeit without doing any damage. The three carriers soon located D Company and continued forward firing in support of the beleaguered defenders. On seeing the carriers approaching through the trees many of the survivors from D Company stood and cheered. Yet after realising his section was on its own Richards decided to disembark 2 Platoon before looping back through the artillery fire to rejoin the troop. Meanwhile, after completing the final stretch of the advance on foot Dinham moved his platoon to a position on D Company's eastern flank and started to dig-in, awaiting the arrival of the remainder of A Company. To the west Roberts and the three remaining carriers of 3 Troop had resumed the advance and linked up with Richards at a junction in the road 300 m south-west of D Company. Townsend arrived with elements of his headquarters aboard three more carriers at 18:50. Following a number of uncoordinated manoeuvres by the APCs, Townsend took command and with the light failing, he ordered Roberts to assault from the west into the flank of the main Viet Cong force.

Bolstered to nine M113s, 3 Troop again moved forward through the artillery fire with Roberts spreading the additional APCs across the rear of his formation to afford depth. Utilising a track as a guide he reformed the troop into a wide assault formation. Beginning the advance at 18:55, 3 Troop prepared for a frontal assault on the Viet Cong force. Arriving at the rubber tapper's hut, Roberts change direction to the north. Linking up with D Company, the APCs moved through the company position. Continuing past D Company to their left, the relief force moved forward rapidly, firing their machine-guns. A brief but heavy engagement occurred, with the Viet Cong responding with automatic fire, including tracer and explosive rounds, which enveloped 3 Troop from their front and left, but was mostly high. Arriving at a crucial point in the fighting, the relief force turned the tide of the battle. The Viet Cong had been massing for another assault which would likely have destroyed D Company, yet the additional firepower and mobility of the armoured force broke their will to fight, forcing them to break contact and begin to withdraw as night approached. At 19:00 the 32 men from B Company finally entered the D Company position, even as the Australian cavalry continued to assault the Viet Cong. After a long and difficult approach under mortar fire and the threat of ambush by a superior force Smith placed Ford on the western side of the D Company defensive position to act as a screen to allow them to treat their wounded and prepare to resist a counter-attack.

3 Troop swept forward with the APCs continuing to assault a further 500 m before Townsend ordered their return. Turning north-west, Roberts moved back to the company location at 19:10. Yet even as they did so the Viet Cong continued to attack from the north-east, although this too was soon broken off. Around the perimeter the Australians engaged the withdrawing Viet Cong with their rifles and machine-guns, while the APCs moved into a line from north to south on the eastern side of the company position. A Company disembarked and took up firing positions between the vehicles, joining 2 Platoon. The artillery had been almost constant throughout the battle and had prevented D Company from being destroyed. By 19:15 the firing had ceased and as darkness fell the Australians prepared for the Viet Cong to mount another attack. Although snipers continued to engage the Australians there were no further assaults and the battle came to a conclusion. The APCs formed a hollow square around D Company. With the Viet Cong at least temporarily driven off, the Australian position was now more strongly held and additional ammunition had been brought in by the APCs, but it was now dark and they would be unable to receive further reinforcement, while the ability of the Viet Cong to mount a night attack was unknown. Meanwhile, the expenditure of artillery ammunition had been high and an urgent demand for 1,000 rounds was submitted by 1st Field Regiment, RAA at 19:30 in case the fighting continued. However, with arrangements for the emergency aerial resupply of Nui Dat by night still being worked out, and with a road resupply by 1 ALSG in danger of being ambushed, it took several hours for the rounds to be loaded and delivered by US Army CH-47 Chinook from Vung Tau.

Townsend assumed command of the position as the Australians regrouped, while Kirby co-ordinated the collection of the dead and wounded. At 20:50 Townsend radioed Jackson, reporting that one his platoons had been destroyed and that D Company was "non-effective", with five dead, 16 wounded and 16 men still missing. Viet Cong losses were believed to have been heavy; however, with no confirmed casualty figures it was beginning to look to the Australians like they had suffered a major defeat. The two officers agreed it would be impossible to secure the battlefield or to attempt to locate the missing from 11 Platoon in the darkness, and after it became clear the Viet Cong were not going to counter-attack, Townsend ordered a withdrawal to a position 750 m to the west from where their casualties could be evacuated. Handling the dead and wounded proved a slow process but with the casualties finally loaded onto the carriers D Company left at 22:45, while B and A Companies departed on foot 45 minutes later. Roberts established a landing zone by forming a square and illuminated it with the interior lights of the APCs by opening their top hatches. The artillery ceased as the evacuation commenced with the first casualties being taken out by a US Army Dustoff helicopter, while the remainder were extracted by six UH-1B Iroquois from No. 9 Squadron RAAF. Despite being slowed by the requirement for the helicopters to land without lights, the operation went smoothly and was finally completed after midnight. The last of the casualties were taken out by 00:34, and they were flown to the Australian hospital at Vung Tau.

During the night the artillery continued to fire on likely Viet Cong forming-up points, although 11 Platoon's final position was avoided for fear of hitting any survivors. Meanwhile, US aircraft bombed targets on likely withdrawal routes to the east. Forming a defensive position ready to repulse an expected attack the Australians remained overnight, enduring the cold and the heavy rain. Although they were now in a better position to hold off any subsequent attack, further reinforcement from 1 ATF at night would be a difficult proposition and was unlikely. Yet with the Viet Cong spent no further attack was mounted. Smith and Townsend spent the night in the back of one of the carriers planning the clearance of the battlefield and the follow-up of the Viet Cong, which was scheduled for the following day under the codename Operation Smithfield. Jackson stipulated the force was to remain within artillery range, but would otherwise have freedom of action to complete the exploitation over the next two to three days. Townsend requested the remaining APCs bring out 6 RAR headquarters, C Company and a section of mortars the following morning, while D Company, 5 RAR would also be placed under his command for the operation. However, with a company from 5 RAR still in Binh Ba, the bulk of 1 ATF's remaining combat power would be deployed as part of the clearance, leaving just two infantry companies from 5 RAR to defend Nui Dat. Smith was determined to recover the missing from 11 Platoon and despite its losses D Company would lead the assault.

Clearing the battlefield, 19–21 August 1966
By morning the weather had cleared. At 06:55 the remainder of 6 RAR departed Nui Dat with 2 Troop, 1st APC Squadron, while D Company, 5 RAR departed at the same time aboard a number of US Army helicopters. Meanwhile, at 07:40 Jackson arrived at 6 RAR's night location to observe the clearance, flying in as Townsend gave his orders for the operation. Stepping off at 08:45, the Australians returned to the battlefield in force while artillery and airstrikes continued to pound the area. The battalion group moved in a "two up" formation with D Company, 5 RAR and D Company, 6 RAR both mounted in APCs as the forward left and forward right assault companies, followed by A, B and C Companies in depth, each of which were dismounted. The assault companies planned to sweep the area then dismount and commence a detailed search, while the other companies would clear the surrounding features and begin the follow-up. Moving cautiously in case the Viet Cong launched a counter-attack, the Australians advanced on an axis following the route used by D Company, 6 RAR the previous day. The battlefield was a scene of devastation, with many of the rubber trees stripped of their leaves and branches and bleeding sap, while the area around D Company's final position was heavily cratered by artillery fire. At 09:21 D Company, 5 RAR reported finding the body of a dead Viet Cong soldier, while half an hour later D Company, 6 RAR found 12 to 15 more. A large number of Viet Cong dead were subsequently found around the area, including a 60 mm mortar crew killed by indirect fire. At 10:20 a bulldozer was requested to bury the bodies of approximately 100 Viet Cong soldiers.

As the scale of the losses suffered by the Viet Cong were revealed it became clear D Company had in fact won a significant victory. By late morning a total of 113 bodies and two wounded had been found, while numerous drag marks and blood trails indicted many more casualties had been removed from battlefield the previous night. With the clearance continuing two wounded Viet Cong still bearing arms were killed by D Company, 6 RAR after they moved to engage them, while in a separate incident another wounded soldier was also killed. A third wounded Viet Cong was later captured and all three were given first aid before being evacuated. These events later caused controversy when journalist Ian Mackay published claims in 1968 that the Australians had deliberately killed unarmed Viet Cong wounded, citing a "witness" to the alleged incident, while a major newspaper misleadingly stated they had killed wounded "civilians". Yet an official investigation determined the allegations were exaggerated and based on hearsay, with the soldier claimed as the source found not to have been present during the fighting and those killed confirmed to have been armed. Similar accusations were made in 1986 by Terry Burstall, a former D Company soldier who claimed up to 17 wounded Viet Cong had been executed, although Burstall's accusations were also refuted and his credibility challenged. However, in 2000 Buick admitted in his memoirs to having killed a mortally wounded soldier the day after the battle as an act of mercy. Burstall argued this may have constituted a breach of the Geneva Convention, while Buick's decision to publish the book was questioned by the President of the Australian Long Tan Association, John Heslewood, who was a private in 11 Platoon during the battle. Mollison later also criticised Buick's action in killing the badly wounded soldier.

Meanwhile, at 11:00 6 RAR reported they had located the missing men from 11 Platoon, their bodies found lying in a straight line where they had fallen, largely undisturbed and still holding their weapons. The majority were from 6 Section, which had been the first to be hit. One of the men was found to have survived despite his wounds, having spent the night on the battlefield in close proximity to the Viet Cong as they attempted to evacuate their own casualties. Earlier a second wounded soldier had also been found nearby, leaning against a tree but still alive. Both men were evacuated, and later recuperated in hospital. Thirteen Australian dead were also recovered, accounting for all the missing. As the search continued Viet Cong dead were found up to 500 m south-east of the position reached by 11 Platoon. A large bunker complex was also uncovered which included 200 pits with overhead protection sufficient for a battalion; however, its layout suggested it had been constructed as a defensive position rather than for an ambush. A further position of 100 pits was also found to the east. By 14:35 the total number of Viet Cong dead was reported as 168, while a large amount of weapons and equipment were also uncovered, including assault rifles, mortars, light machine-guns, sub-machine guns, and a RCL as well as ammunition and grenades. By 18:10 the number of Viet Cong dead had risen to 188, with shallow graves dug by the Australians to bury them where they had fallen.

Due to the likely presence of a significant force nearby the Australians remained cautious as they searched for the Viet Cong. Over the next two days they continued to clear the battlefield, uncovering more dead as they did so. Yet with up to two Viet Cong battalions still believed to be in the area and with the continued vulnerability of Nui Dat to attack from the 274th Regiment, Jackson lacked the resources to pursue the withdrawing force. Company patrols continued to search up to 1500 m east, and to the north of the Nui Dat 2 feature. The Australians subsequently expanded their search to include the area contested during Operation Hobart. A number of tracks were discovered with telephone cables running along their length, as well as further drag marks, blood stains, discarded equipment, fresh graves and evidence of use by heavy cart and foot traffic. The main Viet Cong withdrawal route was discovered after midday on 19 August, running east away from the scene of the fighting. Townsend requested permission from Jackson to follow it believing he had sufficient forces for a pursuit, but Jackson would only permit 6 RAR to advance a further 1000 m so as to remain within artillery range and would not allow the guns to move forward from Nui Dat to increase the range of their protective fire. By 20 August the Australians had counted 245 Viet Cong dead, while scores more were found later. Up to four weeks after the battle decomposed bodies were found in the area, while numerous graves were also located, none of which were included in the estimates of Viet Cong losses. D Company, 5 RAR returned to Nui Dat early on 21 August, while D Company, 6 RAR was also withdrawn for two days leave in Vung Tau.

The remainder of 6 RAR continued the search, with A Company discovering a series of freshly built and recently abandoned hides along the Viet Cong withdrawal route which were believed to have been prepared as delay positions. An older defensive position of approximately 40 pits was also found, while C Company located a makeshift hospital close by which contained 14 graves. Both had recently been occupied. Later an Australian light observation helicopter reported the presence of scattered groups of civilians, with the largest including up to 30 to 40 people, mostly women, carrying baskets and bags, while others had ox carts and were believed to be carrying medical supplies. These reports were followed up by the 1st APC Squadron and a number of military age males were detained for questioning. The infantry companies completed their search tasks by midday, moving to the edge of the rubber plantation, 500 m north-east of Long Tan. Operation Smithfield concluded at 17:00 with the Australians returning to Nui Dat by helicopter and APC by 17:30. They had hoped to catch the survivors of the 275th Regiment and D445 Battalion before they were able to return to their mountain sanctuaries, but the operation proved unsuccessful in preventing their withdrawal. A number of Australian officers later questioned the caution with which it was conducted. Yet Jackson had been unable to mount a pursuit due to the continued threat posed by the 274th Regiment, which was still believed to be in the area. With 1 ATF lacking the resources required for such an operation the opportunity to trap and destroy the Viet Cong while they were still vulnerable was lost and they made good their escape.

Casualties
Viet Cong and North Vietnamese casualties included 245 dead left on the battlefield and three captured, while many more were thought to have been removed as they withdrew. Others were so badly mutilated their remains were unidentifiable. Approximately half were estimated to have been caused by artillery and the remainder by small arms. In addition, the Australians believed the Viet Cong had evacuated up to a further 350 casualties, including an unknown number of dead buried along the withdrawal route. With such losses representing the operational strength of two battalions, Australian intelligence later assessed that the 275th Regiment, which had borne the brunt of the fighting, would not be capable of mounting a regimental-sized operation for several months after the battle. Meanwhile, D445 Battalion, which was thought to have played only a supporting role was believed to have suffered less heavily, was assessed as still being capable of engaging forces up to company size, with a remaining strength of 300 men. Weapons recovered included 33 AK 47 and five SKS assault rifles, seven RPD light machine-guns, four RPG-2 rocket launchers, two 57 mm RCLs, two M1 carbines, one PPSh-41 submachine-gun, one SGM heavy machine-gun, one M1 Garand, one Thompson submachine-gun and one Browning Automatic Rifle. More than 10,500 rounds of small arms ammunition was also found, as well as 300 hand grenades, 40 mortar rounds, 22 RCL rounds and 28 RPG-2 rockets. Australian losses were also heavy and amounted to 17 killed, one died of wounds and 24 wounded; approximately one third of the initial force engaged. A high proportion were National Servicemen, a statistic which later drew criticism in Australia where conscription for overseas service was increasingly controversial. The government later limited the number of conscripts to no more than 50 percent per unit, requiring a rapid and disruptive reorganisation within 1 ATF.



In the aftermath both sides claimed success. Heralded as an Australian victory against overwhelming odds, the battle was widely covered in the Western press, with its results making headlines in Australia and the United States. In the days that followed 1 ATF received congratulatory messages from the American, South Vietnamese and Australian military commands in Vietnam and from the Prime Minister, Harold Holt. Westmoreland considered it one of the more spectacular allied victories to that point in the war, coming after the early successes against the communist offensive had passed. Yet despite their losses the Viet Cong also claimed to have inflicted a heavy defeat on the Australians. Shortly afterwards leaflets circulated throughout the province stating that "...700 Australians were killed, one battalion and two companies were destroyed, and two squadrons of APCs". Similar claims were repeated on Radio Hanoi on 27 August 1966 and the following day on Radio Peking. In contrast, the communist history of Dong Nai Province published in 1986 gave little attention to the battle, although claimed to have "...eliminated 500 Australians and destroyed 21 tanks...", while Viet Cong and North Vietnamese losses were not recorded. D445 Battalion was later honoured with a PAVN heroic unit citation, while the 275th Regiment may have received a similar award. Meanwhile, many Viet Cong soldiers were awarded Certificates of Commendation for their role in the fighting.

D Company, 6 RAR was awarded a US Presidential Unit Citation by Lyndon Johnson on 28 May 1968. The Royal Australian Regiment and 3rd Cavalry Regiment were later awarded the battle honour "Long Tan", one of only five presented to Australian units during the war. Seventeen Commonwealth decorations were awarded to Australian and New Zealand soldiers, including Smith who received the Military Cross (MC) and Kirby the DCM, while Roberts, Kendall and Sabben were mentioned in dispatches, Stanley received the Order of the British Empire and Buick the Military Medal. Both Townsend and Jackson later received the Distinguished Service Order (DSO), although these awards were made on the basis of their entire period in command, rather than solely for their actions during the battle. Twenty-two Australians also received South Vietnamese gallantry medals, although due to official policy regarding foreign awards they were not permitted to wear them until 2004. The limited number of awards later became the subject of considerable criticism. At the time the allocation of awards under the Imperial honours system was based on a quota and this resulted in a number of the original recommendations being downgraded or not awarded, with Smith originally nominated for the DSO, Sabben and Kendell the MC, and Sharp a posthumous mention in despatches. In March 2008 a review recommended awards made to three of the officers be upgraded by the issue of equivalent medals in the modern Australian honours system. Smith was subsequently awarded the Star of Gallantry, and Kendall and Sabben the Medal of Gallantry. Following further review in 2009 Dohle's award was upgraded to the Distinguished Service Medal, while D Company, 6 RAR was awarded a Unit Citation for Gallantry on 18 August 2011.

Assessment
Despite being heavily outnumbered, D Company held off a regimental assault supported by heavy artillery fire, before a relief force consisting of cavalry and infantry fought their way through and finally forced the Viet Cong to withdraw. Although initial estimates of the Viet Cong force ranged from several companies to a battalion, following the battle Australian intelligence assessed it as having totalled between 1,500 to 2,500 men, while 1,000 men were believed to have directly engaged D Company. Achieved against odds of ten to one, the fighting left one-third of D Company killed or wounded. A decisive Australian victory, Long Tan proved a major local set back for the Viet Cong, indefinitely forestalling an imminent movement against Nui Dat and challenging their previous domination of Phuoc Tuy Province. Although there were other large-scale encounters in later years, 1 ATF was not fundamentally challenged again. The battle established the task force's dominance over the province, and allowed it to pursue operations to restore government authority. Yet such battles were atypical of the Australian experience, and although 1 ATF invariably inflicted heavy casualties on the Viet Cong when encountered in large numbers, such actions were less important than routine patrolling in separating the guerrillas from the population and maintaining constant pressure on them, coupled with pacification operations to extend South Vietnamese control. Nonetheless, Long Tan represented a watershed in the campaign, increasing the confidence of the Australians in their ability to defeat the Viet Cong and enhancing their military reputation. Honoured in Australia ever since, in time the battle became part of the legend of its involvement in the war. The best known of the Australian Army's actions in Vietnam, it has assumed a similar significance as battles such as Gallipoli, Kokoda and Kapyong. The date it was fought is observed annually as Long Tan Day and is also known as Vietnam Veterans' Remembrance Day, the national day of commemoration of the Vietnam War.

Although halted at the time of the clash, prior to the encounter the 275th Regiment had been advancing with two battalions forward and one in depth, while at least two companies from D445 Battalion were on its southern flank. The six to eight-man squad first contacted by 11 Platoon was probably a standing patrol moving into position ahead of the main force, and may have been the first indication they received of the Australian patrol. 11 Platoon had drawn ahead of the others due to its rapid follow-up and was isolated when the remainder of D Company was forced off the line of march by mortar fire and then halted. As a result it could not be supported and was cut-off. Regardless, their steadfast defence was critical in holding up the Viet Cong as they moved east, gaining time for the relief force to arrive. After pinning down 11 Platoon frontally, the Viet Cong repeatedly attempted to outflank them but were interrupted by 10 and then 12 Platoon as each tried to move to their aid. The initial dispersion of the Australian platoons made it difficult to locate their flanks, while after D Company concentrated it had been attacked from the south-east, with supporting efforts from the east, north-east and south, all of which were halted by small arms and artillery. The combination of indirect fire and the reverse slope on which they found themselves afforded a degree of cover, while mist from the heavy rain provided some concealment. Meanwhile, a large force—likely a company from D445 Battalion—had been observed moving around the southern flank, and was only broken up by the cavalry after fears it might be ambushed on leaving Nui Dat proved groundless. Although D Company had initially been protected by indirect fire, the mobility and firepower of the cavalry proved decisive. On the verge of being surrounded when the relief force arrived, they would have been quickly overrun had the Viet Cong succeeded. "A very close thing indeed...", Jackson believed another 15 minutes would have seen D Company destroyed, while A Company and 3 APC Troop "...undoubtedly saved the day."



The reasons for D Company's success included superior radio communications which had allowed Stanley to co-ordinate the fire of the guns at Nui Dat, the weight of the artillery which repeatedly broke up the assaulting formations, its timely aerial resupply which prevented them from running out of ammunition, and the mobility and firepower of the APCs in the relief force which finally broke the Viet Cong's will to fight. The battle highlighted the power of modern weapons and the importance of sound small-unit tactics, and has since been cited as an example of the effect of combined arms, demonstrating the effective coordination of infantry, armour, artillery and aviation. Artillery had been the mainstay of the defence, with D Company supported by twenty-four guns from the 1st Field Regiment, RAA and A Battery, US 2/35th Artillery Battalion. Indirect fire provided close protection to the infantry, allowing D Company to hold their line and repulse any Viet Cong soldiers that succeeded in getting through the barrage. Likely forming-up positions and withdrawal routes had also been heavily engaged throughout the battle. In total 3,198 rounds of 105 mm ammunition were fired by the Australian and New Zealand field guns and 242 rounds of 155 mm high explosive by the American medium battery. Ultimately the Viet Cong made the error of attacking within range of the artillery at Nui Dat and had to withstand the fire of three field batteries and one medium battery as a result. Meanwhile, Long Tan also confirmed the importance of armour to support infantry, even in dense jungle.

In the wake of the battle the Australians were left to speculate on the reason it had occurred. One hypothesis was that the Viet Cong had intended to attack and overwhelm Nui Dat, with the initial plan to mortar the base to draw a response force into an ambush after which the base would be attacked and captured, but that they had been prevented from doing so after clashing with D Company. A second possibility was that the operation may have had the more limited aim of drawing D Company into an ambush in an attempt to destroy it and secure a small victory over an isolated force. Finally, it was possible no ambush was planned at all, and that the Viet Cong had been moving on Nui Dat in regimental strength when they were unexpectedly intercepted by D Company, resulting in an encounter battle. The evidence suggested they had intended an attack on Nui Dat in some form, while the lack of prepared positions from which to mount an ambush made this unlikely. Jackson believed the Viet Cong had been on their way to attack Nui Dat on the night of 18/19 August when D Company intercepted them and this was supported by information from a prisoner captured after the battle. Certainly they were carrying large quantities of ammunition and may have had sufficient strength to seriously damage the base, even if its defences were likely strong enough to withstand such an attack. Yet, from the earliest Jackson had been of the opinion the Viet Cong would have to engage 1 ATF in a major battle if they wished to retain control of Phuoc Tuy, and this interpretation fitted his previous thinking. In dispatching patrols east of Nui Dat following the mortar attack on 16/17 August Jackson seemingly reacted to his opponent's first move, and in so doing may have allowed himself to be shaped into responding as the Viet Cong had intended.

In his after action report Townsend stated he believed D Company had disrupted a regimental attack on the 1 ATF base. Yet years later he stated that he doubted whether the Viet Cong ever intended attacking Nui Dat. He felt they would have gained more from attacking a soft target such as Ba Ria and that the defences at Nui Dat would have been sufficient to withstand a regimental assault, having been improved significantly in the 11 weeks since its occupation and protected by patrols and overwhelming artillery support, even if they were still to be fully developed. However, there were suspicions a battalion from the 274th Regiment was moving towards Nui Dat from the west at the same time the 275th Regiment approached from the east, and if true such an attack may have been feasible, even if it still would not have achieved the nine to one superiority communist doctrine required. The southern side of the base was only lightly defended and an assault from that direction would have allowed the Viet Cong to attack the gunline first, and if they succeeded in breaking in they would have then crossed 500 m of open ground before reaching Headquarters 1 ATF. On the other hand Ford believed the mortar attack served to lure an Australian reaction force into an ambush, arguing the Viet Cong would have been unlikely to telegraph their intentions to attack Nui Dat and that they had left a clear trail for any force dispatched to find the mortar base plate and RCL positions. Townsend disagreed, arguing the mortar crews and RCL teams had actually tried to hamper the follow up by breaking into small groups, indicating that no such trap had been planned. Meanwhile, Honnor believed the bombardment had been used by the Viet Cong to register targets and that D Company had stumbled across the force as it was preparing to launch an assault on Nui Dat two days later, with the battle that ensued preventing this from occurring.

A year following the battle, Nguyen Van Nuong (alias Loc), a Viet Cong soldier who had rallied under the Chieu Hoi program, claimed to have been second-in-command of a platoon from D445 Battalion at Long Tan. During questioning he stated they had planned to destroy Nui Dat to allow further operations in Phuoc Tuy, and that the force had consisted of three battalions from the 275th Regiment, together with D445 Battalion and a number of medical units; in total some 2,000 men. The Viet Cong had estimated Australian strength at Nui Dat at 3,000 men and that the plan had been to mortar the base to draw a response force into an ambush by two battalions from the 275th Regiment and D445 Battalion, while the remaining battalion would capture Nui Dat. They expected to quickly overwhelm the ambushed force as well as any relief force, thereby leaving the base relatively undefended. Loc said D445 Battalion's role was to close the rear of the ambush and that they suffered only light casualties during the battle. Despite Viet Cong claims he believed only 100 Australians had actually been killed or wounded, and that the official number of Viet Cong casualties was 200 killed, although he had seen more than that number on the battlefield and believed many more had died during the fighting. According to Loc the Viet Cong were concerned about 1 ATF's capabilities and would attempt to avoid contact in future. In accounting for the fact Nui Dat ultimately escaped attack the intelligence officer who interrogated Loc surmised that D Company may have entered the killing zone before the ambush was prepared and because of this the third battalion may have been unable to be released. Other possibilities included the Viet Cong being forced to abandon that part of the plan by the weight of the Australian artillery or that they had overestimated the size of the Australian force and retained the third battalion to complete the ambush.

The information provided by Loc was consistent with that already known or suspected by 1 ATF, and other than a single battalion overwhelming Nui Dat, it was considered plausible. Yet Smith was adamant D Company had not been ambushed, believing the action to have been an encounter battle regardless of what may have been planned. He argued the troops in the rubber plantation were not sited for an ambush, while the presence of 2,000 to 3,000 men so close to Nui Dat without prepared positions indicated they were still moving when the initial contact occurred. Equally, D Company had been left in possession of the dominant terrain and was not drawn into a killing zone as the plantation offered too much concealment, no attempt had been made to cut them off from any relief force sent from Nui Dat, no artillery or mortars were fired into the engagement area, while the thick vegetation to the north prevented the Viet Cong from manoeuvring into a favourable position. He reasoned that if they had planned to mount an ambush it would have been more effective near the original base plate position as that was the only location they could have been sure the Australians would investigate given they would have had no way of knowing D Company would move another 1500 m east after their handover with B Company where they contacted the 275th Regiment. Finally, communist ambushes were doctrinally completed in less than three hours, but Long Tan had continued for over four and as such Smith concluded that since the tactics used by the Viet Cong had been contrary to many of the principles of an area ambush the battle was unlikely to have been one. Arguably though too many facts are missing to make a conclusive assessment of Viet Cong intentions. To date though no definitive Vietnamese account of the battle is available, while those that exist are contradictory or unreliable.

In 1988 several former PAVN officers, including Hong and Kiem, claimed no more than two battalions had been involved in the battle—less than half the most conservative Australian estimate. Kiem claimed the primary force consisted of D445 Battalion reinforced by one company of North Vietnamese from Headquarters Military Region 7, a total of 720 men, while Hong stated one battalion from the 275th Regiment had also been involved, and that with D445 Battalion its total strength was 700 to 800 men. They believed an entire Australian battalion had been engaged along with two squadrons of APCs, and that the relief force consisted of 1 ATF's second battalion, while the Australians had suffered hundreds of casualties, citing a BBC broadcast which reported 500 killed and 21 tanks destroyed. In contrast Viet Cong losses were claimed to have been significantly lower, with Kiem estimating the total number of dead and wounded as approximately 30, mainly from artillery fire. Hong agreed, stating the figure of 245 killed was exaggerated by a factor of ten. Yet this may only have been accurate for D445 Battalion, and was at odds with Viet Cong records later captured by US forces, with the diary of the commander of the 275th Regiment indicating that unit's losses as 500 men killed. However, total losses may have been even higher still, with 1 ATF reportedly uncovering documents during Operation Marsden in 1969 which listed casualties of 878 killed, died of wounds or missing and 1,500 wounded. Such claims also contradicted the Dong Nai history which stated both the 275th Regiment and D445 Battalion had been involved. Indeed the majority of the dead buried after the battle were wearing green uniforms, and this, coupled with their weapons and equipment, indicated they were either main force Viet Cong or North Vietnamese. Of the three wounded prisoners one was from D445 Battalion and the other two were North Vietnamese who thought they were attached to the 45th Regiment, unaware their unit changed name to the 275th Regiment when operating in the south. According to them it was the artillery battalion of this regiment which had bombarded Nui Dat.

Both Kiem and Hong claimed the plan had been to mortar Nui Dat to draw a reaction force into an ambush, not to attack the base itself. They confirmed the dual military and political aim, emphasising the disruption 1 ATF had caused by lodging at Nui Dat and the intention to affect Australian public opinion. The forced evacuation of Long Tan and Long Phuoc had curtailed the Viet Cong who regarded it as a liberated area, and it was chosen as the ambush site to demonstrate to the local population they were still able to operate effectively despite the Australian presence. Hong explained that the ambush was sprung within range of the artillery at Nui Dat because they correctly assumed no Australian reaction force would move outside the cover it provided, and instead planned on rapidly closing with and destroying it before artillery or air support could be brought to bear. According to Hong they planned to occupy prepared positions in the Long Tan rubber plantation and destroy whatever force the Australians sent to locate the mortars following the attack on Nui Dat. A stop force had been placed to the east, while another was deployed to the south to hold the Australians in place, reasoning the thick undergrowth to the north would force them between the two. D445 Battalion was then to close the rear of the ambush, attacking from the north-west. A larger ambush would then have been staged outside artillery range along the withdrawal route subsequently used by 275th Regiment. Meanwhile, the 274th Regiment was positioned north of Binh Ba astride Route 2 to ambush US forces should they attempt to relieve 1 ATF. Hong later expressed amazement the Australians could consider the battle a victory: "How can you claim a victory when you allowed yourselves to walk into a trap that we had set? Admittedly we did not finish the job, but that was only because time beat us and your reinforcements arrived. I mean you did not even attempt to follow us up. How can you claim a significant victory from that sort of behaviour?"

While the plan outlined by Hong had many of the components of an annihilation ambush, and drawing the enemy out his base areas was a standard communist tactic, a number of weaknesses were evident, including the lack of a means of neutralising the Australian artillery, the absence of indirect fire weapons in the ambush, and the comparatively small size of the ambushing force. Equally the plan to site a second ambush outside artillery range would have been ineffective as the Australians were unlikely to proceed that far unless their guns had followed. Hong believed the ambush failed because the soldiers at the front—those which faced 11 Platoon—fired before the entire Australian force entered the killing zone, while it should have been opened from the rear against 12 Platoon. Had D Company been attacked from the rear the battle would indeed have been more like an ambush, and they would have been in immediate danger, while it would likely have been irrelevant if the forward Viet Cong troops fired first as the Australians were already well into the plantation. Yet they had been unable to co-ordinate such a manoeuvre and D445 Battalion had more than three hours from the initial contact to close the gap at the rear and failed to do so. Regardless, a number of issues cast doubt on this version of events. Firstly, if the Viet Cong had been in the plantation on 17 and 18 August preparing an ambush they would likely have been identified by the patrols from A or B Company, 6 RAR. Secondly, the alleged size of the force is questionable as just 700 men would have been insufficient to be certain of success, while according to communist doctrine it would have required more than a regiment to achieve overwhelming force. In the end the reaction of the Viet Cong indicted they had not detected D Company's presence in the rubber plantation until the first clash with 11 Platoon.

In 2005, Nguyen Nam Hung—deputy commander 274th Regiment—claimed the Viet Cong had indeed intended to destroy 1 ATF and liberate Ba Ria province. Hung stated that a two-phased offensive had been conceived, planning first to draw the Australians into the open and destroy them in an ambush, and then attack the weakened base at Nui Dat. Ultimately though their goal had been political and the capture of Nui Dat was not considered important. According to the official D445 Battalion history, the officers of the units involved meet in early August to finalise plans for the attack. The account claimed that following the mortar attack on 16/17 August, the force had formed up in a 3 km wide semi-circle at 10:15 on 18 August to lie in wait, with the 275th Regiment given the "middle battle" position and tasked with springing the ambush, while other units from the 275th Regiment and one company from D445 Battalion occupied the "front block" position near the village of Long Tan, and two companies from D445 Battalion under the command of Major Sau Thu had been tasked with occupying the "back block" position to encircle the Australians by sweeping beneath their "tail" and destroying them. In support, the 80-strong Vo Thi Sau militia company, most of them women, was located nearby to help drag away the wounded following the battle. Thu later confirmed he had been ordered to lure the Australians out of Nui Dat, kill as many as possible, capture their weapons, and overrun the base. Yet this explanation also suffers from inconsistencies. In particular, the delay of over a day between the mortar attack and the battle suggests another purpose, and it is possible it may have served to test the Australian reaction and the speed with which counter-battery fire could be directed against them in preparation for a full-scale attack.

While Vietnamese statements consistently maintain an ambush was planned at Long Tan, whether they also intended attacking Nui Dat remains uncertain. The fact a large Viet Cong force had not been identified in the rubber plantation prior to midday on 18 August suggests no such force was there, and consequently they could not have been occupying an ambush position waiting for the arrival of the reaction force from Nui Dat. Regardless, it seems likely the 5th Division did plan to ambush the Australians, although they seem to have been ill-prepared due to a lack of co-ordination which occurred following the morning of 17 August and the selection and occupation of the intended site. As a result they appear not to have been ready when D Company entered the plantation and were likely somewhere on its eastern edge instead. The Viet Cong were probably still conducting their reconnaissance and establishing the ambush in the vicinity of where the rubber met the jungle when the battle occurred and it seems likely the Australians upset their plan, perhaps moving faster than the ARVN and US troops they had previously fought. What followed appears to have been an encounter battle as the two advancing forces clashed on open ground in a meeting engagement. An alternative explanation is that the Australians may have approached from an unexpected direction, physically dislocating the ambush. Indeed, according to Thu "...we didn't know how many... [the Australians] had in Nui Dat. We tried to draw them out... We thought they would go one way but... [they] went the wrong way and came behind us." In July 2006, Sabben and Buick visited the battlefield for a television story on 60 Minutes, where they met Nguyen Minh Ninh, former vice-commander D445 Battalion. Minh told them: "You won. But we won also. Tactically and militarily you won—but politically, we won. In this battle you acted out of our control—you [escaped] from our trap." According to journalist Cameron Stewart it was the first time a senior North Vietnamese officer had admitted being defeated at Long Tan.

Although D Company ultimately prevailed they would have been defeated were it not for the timely arrival of the cavalry and the availability of significant artillery support. The battle had come close to disaster for the Australians and brought home the dangers of a dismounted platoon or company being overwhelmed by a larger force. A number of deficiencies had been evident in 1 ATF's preparation and response to the battle. As the fighting began there was no ready reaction force available at Nui Dat, and this resulted in a lengthy delay reinforcing D Company. After Long Tan a rifle company with armoured support was dedicated to this role, on standby to respond to an attack or exploit any opportunity. Meanwhile, the Viet Cong had been armed with weapons at least equal to those used by the Australians. Most had carried modern Soviet assault rifles, as well as a large quantity of ammunition, which allowed them to sustain a high rate of fire. In contrast, the quantity of ammunition carried by the Australians had been insufficient, and following the battle the minimum load was increased to 140 rounds per rifle and 500 for each machine-gun. Equally the aerial resupply of D Company had been delayed because there were no prepacked ammunition holdings available. This also changed, while in future rounds would also be supplied loaded in magazines for quick use. The Viet Cong had also employed 60 mm mortars, but they were no longer standard equipment for Australian rifle companies, and although battalions were issued 81 mm mortars they were controlled by Support Company. Such weapons would afford integral fire support in situations where their opponents had closed within the safety distance of the artillery, and consideration was given to their re-issue. Yet the added weight would limit the ability of sub-units to patrol and M-79 grenade launchers were issued instead, while a number of APCs were modified as mortar carriers.

The magnitude of the battle and its proximity to Nui Dat shocked the Australians, and later it was suggested Jackson had either suspected a Viet Cong regiment was nearby or that after being presented with SIGINT suggesting its presence he refused to accept it. Yet while a number of indicators of the coming action were evident after the battle, in reality no one had forecasted it. Despite 547 Signals Troop detecting a transmitter from the 275th Regiment moving west towards Nui Dat, such intercepts were unable to predict Viet Cong intentions with certainty, while patrols through the area also failed to find it. Regardless, Jackson had responded by maintaining patrols at company strength when outside Line Alpha, while ensuring a level of base security. However, Townsend had not been given access to this intelligence and some officers were later critical of the restrictions placed on its availability. Although it would not have altered the requirement for a company-sized patrol it might have changed the way the battle was fought, and following Long Tan both battalion commanders were regularly briefed on such intercepts. Meanwhile, the value of patrolling in depth and in sufficient strength to disrupt Viet Cong efforts to concentrate their forces was reinforced and while no change to the pattern of Australian operations occurred, when a significant engagement was possible patrols would be required to be a minimum of a company, while platoons and companies would be required to operate close enough to rapidly support each other to prevent them becoming isolated. Lastly, the command relationship between the infantry and APCs had been problematic during the battle and changes to standard operating procedures were implemented to provide clearer direction in such circumstances.

Subsequent operations
A week following the battle US II FFV launched a large-scale corps-sized sweep of Phuoc Tuy on 23 August, known as Operation Toledo. The operation saw the deployment of two brigades of the US 1st Division, the US 173rd Airborne Brigade, the US 1/26th Marine Battalion and two South Vietnamese Ranger battalions in an attempt to destroy the 274th and 275th Regiments. 1 ATF involvement included both 5 RAR and 6 RAR and supporting units. The operation lasted until 8 September and despite the intensity of the previous fighting little contact occurred, with no evidence of a large force having been in the area uncovered. Poorly planned, the operation failed to trap the Viet Cong, while 5 RAR's involvement resulted in only two Viet Cong killed, one wounded and one captured without loss, although a number of tunnels were discovered in Long Tan village and destroyed. In the months that followed 1 ATF conducted a number of search and destroy, village cordon and search, and route security operations in an attempt to further extend its control, and to separate the local people from the influence of the Viet Cong. Such operations usually resulted in contacts between the Australians and small groups of Viet Cong, while during cordon and search operations of Binh Ba and Hoa Long a number of villagers suspected of sympathising with the communists were apprehended and handed over to the South Vietnamese authorities. Several search operations were also conducted by the Australians in areas suspected of containing Viet Cong base camps, and these often resulted in the discovery of recently used and quickly evacuated camps, hospitals and logistic bases which had then been destroyed. Meanwhile, 5 RAR and 6 RAR continued an extensive patrolling and ambushing program around the task force base at Nui Dat.

By December 1966 some Australian officers had begun to reassess their operational aims. Warr argued they should move away from conventional operations and focus instead on population control and disrupting communist supply lines and freedom of movement. Assessing that 1 ATF did not have the strength to destroy the Viet Cong forces then in Phuoc Tuy with just two infantry battalions, he favoured cordon and search operations to eliminate the cadres and block the supply of rice from the villages. On 7 January 1967, Jackson was replaced as Commander 1 ATF by Brigadier Stuart Graham, and he subsequently approved Warr's proposed concept of operations. Two days later 5 RAR conducted a cordon and search of Binh Ba, screening 1,500 villagers and interrogating 591. Nine Viet Cong were captured, while five draft dodgers were also detained, with the operation concluding by mid-afternoon without a shot fired. The Australians considered the operation a complete success and its results were seen to vindicate their evolving tactics, techniques and procedures. In the following months 5 RAR continued to develop cordon and search procedures as 1 ATF extended its influence, with such operations weakening the Viet Cong infrastructure and removing a number of villages from their control. In this manner 1 ATF continued to operate independently in Phuoc Tuy Province, pursuing their own counter-insurgency campaign. Yet differences of opinion between Australian and American methods increasingly produced friction; impatient with the Australian approach, in early-1967 Westmoreland complained to Commander Australian Forces Vietnam, Major General Tim Vincent, demanding a more aggressive approach. However, the Australians were convinced deliberate patrolling techniques were proving effective, and such urgings went mostly unheeded.

In February 1967 1 ATF focused on the Dat Do area and south-east Phuoc Tuy, initiating a program of conventional operations and pacification, with 5 RAR concentrating on cordon and search and civic action against the village cadres, while 6 RAR was tasked with search and destroy missions targeting D445 Battalion. During the first week 6 RAR conducted ambushes along Route 23 between Dat Do and the Suoi Tre river, pre-empting Viet Cong attacks in the area during the Tet holiday. The results were modest, and they suffered a number of casualties from a misplaced fire mission from the 161st Battery, RNZA which killed four and wounded 13, including Kirby who was among the dead. On 13–14 February 5 RAR and South Vietnamese forces completed a cordon and search of An Nhut, west of Dat Do, apprehending 14 Viet Cong suspects, five sympathisers, two deserters and a draft dodger. The Australians again suffered heavy casualties after the officer commanding C Company, his second-in-command, and the artillery forward observer were killed by an unrecorded ARVN mine. Regardless, these operations met with some success, and over a six-day period the battalion captured 40 Viet Cong. Yet even as Graham continued to refine his strategy the Viet Cong struck, and this sudden initiative would force the Australians into the type of conventional engagement Westmoreland had been advocating during Operation Bribie on 17–18 February 1967. During a hard fought battle at close range the Viet Cong lost heavily, yet the disciplined force matched the Australians as both sides stood their ground, inflicting casualties on the other before falling back. 1 ATF sustained its heaviest casualties in the war to that point, losing 16 men killed and 55 wounded in a single week. For the first time in nine months of operations the number of Australians killed in battle, or from friendly fire, mines or booby traps, had reversed the task force's kill ratio and they appeared to have lost the initiative.