its TAOR and conducting operations throughout Phuoc Tuy as required, as well as deploying anywhere in III Corps and neighbouring Bình Thủy in IV Corps 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, north of Ba Ria, while a logistics and support base would be established in Vũng Tàu with a direct link forward via road. Situated on Route 2, Wilton had selected Nui Dat because its 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 VC activity in the area. Astride a major communist transit and resupply route, it was close to a VC 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 VC and the inhabitants. 1 ATF would then focus on destroying VC forces in the province, while security of the towns and villages remained a South Vietnamese responsibility. Initially, 1 ATF consisted of two infantry battalions—the 5th and 6th Battalion, Royal Australian Regiment. Other units included the 1st APC Squadron operating M113 armoured personnel carriers, 1st Field Regiment, Royal Australian Artillery which consisted of one New Zealand and two Australian batteries equipped with eighteen 105 mm L5 Pack Howitzers, 3rd SAS Squadron, engineers from 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 Logistic 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 1 ATF was 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