In June 1963, the main body of the squadron deployed to Wewak, taking over from the 21st Construction Squadron, before returning to Australia in June 1964, having been replaced by the 22nd Construction Squadron. South Vietnam (1966–1971) The most significant part of squadron history was its involvement in the Vietnam War. The squadron was in South Vietnam from 1966 to 1971 and was involved in a wide variety of engineering tasks. The first to deploy was 8 Troop, which was initially based around Vung Tau, although they were later deployed to the 1st Australian Task Force base at Nui Dat in August 1966. At Nui Dat, elements of the squadron took part in the defence of the base during an attack the day before the Battle of Long Tan; amidst heavy indirect fire, three members of the squadron were wounded. 10 Troop relieved 8 Troop at Nui Dat in October, and in February 1967 the squadron's third troop, 9 Troop, was deployed to Vietnam. Early tasks undertaken by the squadron included clearing operations in support of the 5th Battalion, Royal Australian Regiment during Operation Leeton, and sustainment operations. The construction of helipads and land marking operations were common tasks carried out by Plant Troop. In 1967 the squadron completed a 300,000 gallon dam. This provided the Australian contingent with an alternate water supply. At Nui Dat the squadron set up a large quarrying operation in early 1968. The squadron was also involved in the construction of the 1st Australian Logistics Support Group (1 ALSG) base amid the sand dunes at Vung Tau following its occupation in May 1966. Although a detachment of engineers from 1 RAR Group had commenced basic works to prepare the area prior to the lodgement, including a basic water supply and road construction, much work remained. Lacking basic facilities for logistic operations including unloading facilities, roads and hardstanding, 1 ALSG struggled to become operational and commence logistic support to 1 ATF forward at Nui Dat. Meanwhile, basic hygiene and stifling heat were also a significant problem. Urgent work was required and the development plan included cutting and spreading the sand dunes, reclaiming large areas of swamp land, road construction, establishing accommodation, hardstanding, storage areas, workshops and vehicles parks, as well as extensive drainage works. Other tasks included winning construction resources, water purification and supply, electricity generation, survey, bridging and rafting, and civil aid. Helipads were also