1st Australian Task Force The 1st Australian Task Force ( 1 ATF ) commanded Australian and New Zealand Army units deployed to South Vietnam between 1966 and 1972 . 1 ATF was based in a rubber plantation at Nui Dat , in Phuoc Tuy Province . At the Battle of Long Tan on 18 August 1966 , units of 1 ATF defeated a Viet Cong force of at least regimental strength . While the task force was primarily responsible for securing Phuoc Tuy Province , its units , and the Task Force Headquarters itself , occasionally deployed outside its Tactical Area of Responsibility including during Operation Coburg and the Battle of Coral – Balmoral in 1968 . 1 ATF was withdrawn in late 1971 . History . In March 1966 the Australian government decided to increase its commitment to the Vietnam War , 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 ( RAN ) elements would also be deployed and with all three services total Australian strength in Vietnam was planned to rise to 6 , 300 . Meanwhile , the attachment of the 1st Battalion , Royal Australian Regiment ( 1 RAR ) 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 . 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 Cambodia n 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 , 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 had commanded the AATTV and Australian Army Force Vietnam ( AAFV ) 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 . The headquarters of the 1st Brigade was subsequently used to raise 1 ATF . 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 principle 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 , 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 , it 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 . 1 ATF initially consisted of two infantry battalions — the 5th and 6th Battalions , Royal Australian Regiment . 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 batteries equipped with eighteen 105 mm L5 Pack Howitzer s , 3rd SAS Squadron , engineers from the 1st Field Squadron and 21st Engineer Support Troop , 103rd Signals Squadron , 161st Reconnaissance Flight operating Cessna 180 s 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 amid the sand dunes at Vung Tau south , while eight UH - 1B Iroquois helicopters from No . 9 Squadron RAAF also supported 1 ATF from Vung Tau . Although ostensibly independent , US forces provided considerable support including medium and heavy artillery , close air support , helicopter gunships , medium and heavy lift helicopters and additional utility helicopters . Six 155 mm M109 self - propelled howitzers from A Battery , US 2 / 35th Artillery Battalion were also permanently attached at Nui Dat . The largest Australian formation deployed since the Second World War , although many of 1 ATF ' s officers and non - commissioned officers had seen extensive operational service , the task force had been hastily assembled and included many untried National Servicemen . Few of its senior personnel had direct experience of counter - insurgency operations , and even less a first - hand understanding of the situation in Vietnam , while it had been unable to train together before departure . Yet despite these shortfalls 1 ATF was required to rapidly establish itself in a complex operating environment . 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 . 5 RAR deployed from Vung Tau the same day and was tasked with clearing any Viet Cong found in an area 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 . At the Battle of Long Tan on 18 August 1966 , D Company 6 RAR with considerable artillery support held off and defeated a Viet Cong force of at least regimental strength . 18 Australians were killed and 24 wounded , while 245 communist dead were later recovered from the battlefield . The battle allowed the Australians to gain dominance over Phuoc Tuy Province and 1 ATF was not fundamentally challenged again . Regardless , during February 1967 the Australians suffered their heaviest casualties in the war to that point , losing 16 men killed and 55 wounded in a single week , the bulk during Operation Bribie . Yet with the Phuoc Tuy province coming progressively under control throughout 1967 , the Australians increasingly spent a significant period of time conducting operations further afield . Meanwhile , with the war continuing to escalate following further American troop increases , 1 ATF was heavily reinforced . A third infantry battalion arrived in December 1967 , while a squadron of Centurion tank s and additional Iroquois helicopters would also be added in early 1968 . In all a further 1 , 200 men were deployed , taking the total Australian troop strength to 7 , 672 combat troops , its highest level during the war . This increase effectively doubled the combat power available to the task force commander . The New Zealand contribution also increased following the commitment of 1 ATF , with the addition of one and later two infantry companies attached to one of the Australian battalions , in addition to its artillery battery . Meanwhile , in 1969 a New Zealand Special Air Service Troop was attached to the Australian SAS Squadron . New Zealand strength peaked at 552 troops in 1969 . At its height 1 ATF numbered over 8 , 000 men , including three infantry battalions , armour , artillery , engineers , logistics and aviation units in support . 1 ATF was subsequently deployed astride infiltration routes leading to Saigon in order to interdict communist movement against the capital as part of Operation Coburg during the 1968 Tet Offensive and later during the Battle of Coral – Balmoral in May and June 1968 . At Fire Support Bases Coral and Balmoral the Australians had clashed with regular North Vietnamese Army and Viet Cong main force units operating in battalion and regimental strength for the first time in near conventional warfare , ultimately fighting their largest , most hazardous and most sustained battle of the war . During 26 days of fighting Australian casualties included 25 killed and 99 wounded , while communist casualties included 267 killed confirmed by body count , 60 possibly killed , 7 wounded and 11 captured . Other significant Australian actions included Binh Ba in June 1969 , Hat Dich in late - December 1968 and early 1969 and Long Khanh in June 1971 . The Australian withdrawal effectively commenced in November 1970 . As a consequence of the overall allied strategy of Vietnamization and with the Australian government keen to reduce its own commitment to the war , 8 RAR was not replaced at the end of its tour of duty . 1 ATF was again reduced to just two infantry battalions , albeit with significant armour , artillery and aviation support remaining . Australian combat forces were further reduced during 1971 as part of a phased withdrawal . The Battle of Nui Le on 21 September proved to be the last major battle fought by Australian forces in the war , and resulted in five Australians being killed and 30 wounded . Finally , on 16 October Australian forces handed over control of the base at Nui Dat to South Vietnamese forces , while 4 RAR , the last Australian infantry battalion in South Vietnam , sailed for Australia on board HMAS " Sydney " on 9 December 1971 . Between June 1966 and December 1971 1 ATF recorded at least 3 , 370 Viet Cong killed , the majority in Phuoc Tuy , while an unknown number were wounded . Total Australian Army casualties during the Vietnam War were 478 killed and 3025 wounded , the bulk of which were sustained by 1 ATF . Order of battle . 1 ATF ' s organisation varied as Australian and New Zealand units rotated through South Vietnam and the total size of the Australian and New Zealand force in South Vietnam changed . The task force typically consisted of : The Australian Army Training Team Vietnam ( AATTV ) was separate from 1 ATF and reported directly to the Australian Force Vietnam headquarters located in Saigon which provided administrative support to all Australian forces in South Vietnam .