First tour of VietnamEarly in 1966 the battalion learnt that it was to serve in Vietnam as one of two infantry battalions in the 1st Australian Task Force. As it was given only three months notice for its deployment, the training schedule prior to embarkation was hectic. 'Range practices began in the dawn hours and often went until 2200 hours. Nights and weekends were spent training in night movement and conducting lectures on Vietnamese customs, history, culture and language'. Each company trained at Gospers, in the Wiangaree State Forest in New South Wales, as well as at Canungra in Queensland. In March 1966 the battalion emplaned at Aero Paddock at Holsworthy and moved to Gospers for its final exercise, which included advances to contact, night movement, and defensive operations. After this C Company would deploy to Vietnam on HMAS Sydney, whilst the remainder of the battalion flew by air.Upon arrival in South Vietnam the battalion, under Warr's command, commenced operations on 24 May 1966 by participating in the clearance of the 1st Australian Task Force base at Nui Dat – Operation Hardihood. For this operation the battalion was under the command of 173rd (US) Airborne Brigade and worked alongside two American parachute battalions to clear the area out to mortar range, so that the base could be established. It was on this operation that the battalion's first soldier, Private Errol Noack, a 21-year old from Adelaide, South Australia, was killed. Noack was critically wounded during a water resupply and died of his wounds at 36th Evacuation Hospital on 24 May 1966, sixteen days after he said farewell to his family. He was also the first National Serviceman to be killed in Vietnam.Other activities followed: such as the reclamation of Binh Ba (Operation Holsworthy, 7 to 18 August 1966) – a village that would figure prominently during the battalion's second tour; clearance operations following the 6th Battalion's action at Long Tan (Operation Darlinghurst, 26 to 31 August 1966); clearance of the Nui Thi Vai feature to secure Route 15 (Operation Canberra, 6 to 10 October 1966); operations against the village cadres (such as Operation Beaumaris, 13 to 14 February 1967); and searches of the Viet Cong base areas in the Long Hai Hills (Operation Renmark, 18 – 22 February 1967).Attempting to restore the control of the South Vietnamese Government to the areas of population which had been cut off by the Viet Cong (or VC), who controlled many of the villages and the supply routes between the towns, was a key focus for the battalion. It therefore attempted to drive out the village cadres and Viet Cong through cordon and search operations, numerous successful ambushes, and by establishing a good local intelligence network – largely through close relations with the senior members of each village. Many of the villagers did not support the Viet Cong regime due to the heavy taxes they levied, the manner in which they restricted civilian travel to the various markets for trade, and because they conscripted those of military age. As the battalion did not have the manpower to patrol the areas in the north of the province in search of regular Viet Cong units, they chose to concentrate on the villages in an attempt to destroy the Viet Cong power base. This resulted in cordon and search operations of Duc My, Binh Ba, Ngai Giao, Phuoc Hoa, Xuyen Moc and on Long Son Island. These operations were largely successful and the techniques developed in their execution were to be accepted and used throughout the Australian Army. Another sign of the innovations used by the Battalion was the raising, in October 1966, of the first specialist Reconnaissance Platoon to be used in Vietnam. 'Prior to the arrival of 5 RAR only 24,775 of the inhabitants of Phuoc Tuy Province were under South Vietnamese Government control in 24 hamlets. However, by April 1967, 98,408 villagers were under Government control in 105 hamlets. 5 RAR killed 70 Viet Cong... Many hundreds more Viet Cong were captured either in conventional operations or during cordon and search operations. However, the important statistics of the Battalion's tour remain the number of Vietnamese people who supported the Vietnamese Government and the degree of Government control established by 5 RAR during their first tour of Vietnam. 5 RAR had laid a sturdy platform for future battalions due to their innovative use of tactics, hard training, the professionalism with which they carried out their tasks and the subsequent respect won from the Vietnamese people',In total the 5th Battalion conducted eighteen separate operations before it handed responsibility over to 7th Battalion. The battalion returned to Australia in April 1967 and marched through the streets of Sydney on 16 May 1967; 25 men were killed in action or died of wounds, while 79 were wounded in action.Second tour of VietnamThe 5th Battalion commenced its second tour of South Vietnam in February 1969, this time under the command of Lieutenant Colonel C.N. Khan. After shaking out for two weeks, the Battalion began a reconnaissance in force in the northern and eastern parts of the rugged Nui Dinh mountain complex on 1 March 1969 – Operations Quintus Thrust I and II. Other activities followed: reacting to a significant threat against United States forces in the Long Binh and Bien Hoa areas (Operations Federal and Overlander, 10 March to 8 April 1969); ambushing in the Nui Thi Vai mountain complex (Operation Twickenham I, 2 to 13 May 1969); the Battle of Binh Ba, for which the Royal Australian Regiment received a battle honour for its action against a battalion of the 33 NVA Regiment (Operation Hammer, 6 to 8 June 1969); operations to locate and destroy the D445 Viet Cong Battalion (Operation Kingston, 14 September to 15 October 1969); and cordon and searches of the hamlets of Duc Trung, Binh Ba and Duc My (Operations Bondi I and II, 27 December to 16 February 1970).'During the second tour the emphasis [of operations] turned more towards route denial and conventional operations involving seeking out and closing with the guerilla and Main Force units such as D445 Battalion and 274 Regiment. Ambush and reconnaissance tasks were also conducted at platoon and company level. Attacks and the clearance of bunker systems played a major part of operations... The tour [also] saw the extensive use of Australian and United States M113 APCs in support of tasks... Towards the end of the tour, elements of the Battalion also contributed to the pacification process through the construction of schools and housing and through the provision of medical and dental support to such villages as Ong Trinh and Phuoc Le'. Operations were also characterised by a higher number of mine incidents than had been experienced previously. 'The majority of the mines were taken by the VC from a barrier minefield laid by the Australians between the Horseshoe and Phuoc Hai. The enemy used these mines offensively rather than using them to protect their bases. The VC would lay the mines on tracks, in likely ambush and harbour locations, and around houses and villages. During Operations Esso I, II and III in June and July 1969, special precautions were taken to counter the problem of mines. Special training was conducted, all vehicle floors were sandbagged, flak jackets and helmets worn whenever possible, and mine detectors used by all patrols. Despite these precautions, seven soldiers were killed and 43 were wounded by mines on these operations alone'.Arguably the most well known action ever fought by the 5th Battalion was the Battle of Binh Ba, which took place between 6 and 8 June 1969 and saw the defeat of a well armed and determined North Vietnamese Army (NVA) battalion. The action began at 0810 hours on 6 June when a Centurion tank and armoured recovery vehicle moving to a fire support base manned by 6 RAR was fired on by a rocket propelled grenade from one of the houses in the village, located about three miles north of the Australian Task Force base at Nui Dat. D Company, 5 RAR was the Task Force quick reaction force, which also included a tank troop and an APC troop, and was sent out in response to a request for assistance from the local District chief. Whilst determining that the village was clear of civilians, the force came under heavy RPG fire. The Commanding Officer's Tactical Party and B Company joined the action at midday, with B Company being placed in a blocking position to the east of the village. By this time D Company and its supporting arms had fought their way into the centre of the village. 'The fighting was so fierce and confused for two hours that a detailed description is impossible'. By 1400 hours D Company formed up west of the village and began a second sweep, with infantry leading and the tanks and APCs close behind. A difficult combined arms clearance supported by Bushranger helicopter gunships and artillery then took place against determined opposition of the 1st Battalion of the 33rd NVA Regiment. 'The raw leadership of the soldiers was outstanding. Of the twenty one rifle sections involved, twelve were commanded by private soldiers. Two platoons were led by sergeants and one by a corporal... The sweep stopped at last light with the whole force exhausted after eight hours of continual contact'. The clearance of the village and surrounding areas continued over the next two days, involving much of the Battalion. Arthur Burke 'at the gun end of 105 Battery' wrote, 'We've fired more rounds in the last 48 hours than the first 20 days of last month – 2,000 rounds'. One Australian was killed and eight wounded during the battle, whilst more than 90 VC and NVA soldiers were known to have been killed.At the conclusion of its second tour the 5th Battalion again handed over to the 7th Battalion. By the time it returned home in February 1970, the Battalion had carried out some 18 operations during its twelve-month operational tour and suffered 25 men killed or died of wounds, and 202 wounded in action. During its two operational tours in South Vietnam, the Battalion received 45 honours and awards, including two Distinguished Service Orders, two Distinguished Conduct Medals, six Military Crosses, one Medal of Gallantry, five Military Medals, and 29 mentioned-in-dispatches.