Historical Timeline

131 Divisional Locating Battery (131 DLB) was formed in 1954 from 31 Locating Battery, with Major CEH Rich as Battery Commander. This was a Citizens Military Force Unit tasked with survey and sound ranging. In 1957 the Battery moved to a new training depot at West Pymble, then from 1960 it became an integrated Unit under Major Nowill, the ratio being 60% CMF and 40% Australian Regular Army (ARA). The Radar and Transport Sections were located at North Fort, the Survey Section moved to a depot in Manly.

Following the confrontation period with Indonesia in 1964, the Battery took delivery of four AN/KPQ-1 radar sets from the United States. These radars were intended to provide mortar locating coverage for future operations.

On 20th September 1965 the Unit was reformed as an ARA Unit at North Fort under Major Gowans. This marked the formal end of the integrated Locating Batteries. A strong sense of kinship between 131 DLB and CMF sister Batteries – 130, 132 and 133 - has continued. In November 1965 the Battery moved to Kokoda Lines at Holsworthy, as an independent Battery and commenced training for the conflict in South Vietnam (SVN).The first National Servicemen brought the Battery to strength in 1966.

Australian troops were committed to SVN under 1 Australian Task Force in 1965-66. 131 DLB was called on to contribute a Detachment. This first Detachment:

Difficulties were encountered from the start due to the radars’ failure to work properly. However, it was not long before positive results began to be seen:

The Detachment’s first WIA, was from a mortar targeting the Taskforce area on the night of 16-17 August 1966; the wounded were LBdr K Doehrman, and Sgt F Perry. Problems with the radars continued, however US Forces assisted in the provision of spare parts. The Artillery Intelligence Section was active in crater analysis, and on 27 November 1967 confirmed the presence of the RPG7 in the Taskforce Area of Operational Responsibility.

Gnr Tom Checkley was killed in a vehicle accident on 5th August, 1966. The second fatality, on 18th February 1968 was LBdr JL (Jim) Menz who was KIA at Fire Support Base Anderson.

1968 saw the introduction of a sound ranging base at Nui Dat. The Survey Section began to carry out airborne fixation with accurate results being achieved over distances of 18,000 metres.

1969 saw increased enemy 122 mm rocket activity. Listening posts obtained good locations for rocket sites, mainly by flash spotting. The counter battery fire using these locations proved very effective with ground patrols finding the sites and enemy bodies. The year was notable for the decreased use of radars. In July 1970 after four years in SVN, the radars were returned to Australia. A change in the operational setting ended the sound ranging base. It was returned to Australia in October 1970.

With the passing of the radars and sound ranging from the scene the Detachment was tasked with a new responsibility; the sensor program in the Australian TAOR. A total of 33 ‘strings’ of sensors were laid down, with monitoring stations established at Nui Dat and Horseshoe. The intelligence gained by the Section led to the laying of several large and successful ambushes.

1971 heralded the end of Australia’s involvement in the Vietnam conflict. In June the Sensor Section was transferred to 12 Field Regiment. The remainder of the 131 DLB Detachment returned to Australia in July 1971. In the five years in SVN the Survey Section provided survey for over 100 Fire Support Bases throughout Phuoc Tuy and neighbouring Provinces for Australian, United States and ARVN artillery units.