The ubiquitous M113A1 family of armoured vehicles have been supporting, transporting, re-supplying or evacuating Australian soldiers since 1965; many having seen operational service in South Vietnam, Somalia, Rwanda and more recently in East Timor.

The first bulk consignment of the M113A1 arrived in early 1965, the first of 815 vehicles to be acquired by Australia . By May, Australia was providing ground forces to South Vietnam , including a troop of armoured personnel carriers (APCs). The M113A1 proved a real asset in Vietnam as it was able to transport troops into very difficult country.

A typical M113A1 armoured personnel carrier of the Australian Army, equipped with a T50 turret mounting an M2HB .50 cal and an L3A3 .30 cal machine guns. Both the T50 turret and dual machine guns will be things of the past once the rebuild to the new standard is completed.

The M113A1 was intended only as a taxi and not a tank, armed only with a single .50-inch machine gun attached to the commander’s cupola. This was soon shown to leave the commander in a very exposed position, so, in typical Australian fashion, ‘field modifications’ were undertaken by installing armoured shields.

In addition, as an interim measure, the Army procured twenty model 74C turrets from the United States , which fitted directly into the M113A1 without modification. The arming of the M113A1s with twin .30-inch machine guns then gave the commanders some protection. However, they were very cramped and lacked good all-round visibility when closed up. The turret which offered more promise was the Cadillac Gage Company's T50 turret. Although there was some criticism, the T50 turret was considered a definite asset and was subsequently fitted to all Australian APCs.

The M113A1 medium reconnaissance vehicle was a uniquely Australian concept that married the hull of the M113A1 armoured personnel carrier with the turret from a British CVRT Scorpion. It provided the Cavalry Troop with greatly increased firepower. The design was developed by DMO's Land Engineering Agency.

Another unique Australian modification was the up-armouring program developed by the then Army Design Establishment (now DMO Land Engineering Agency). This occurred when it became apparent that a significant proportion of vehicles were being damaged and crews injured in Vietnam as a result of the triggering of mines.

The layout of the M113A1 meant that the driver was particularly vulnerable. Trials carried out during July 1969 indicated that crew injuries would be significantly reduced if the sponson was strengthened by welding additional armour over the first three wheel stations, together with a collapsible foot rest. As a result, sponson up-armouring kits were installed in carriers by the end of August.

Meanwhile, injuries were also being sustained by explosions under other parts of the APCs. After initial investigations, the solution provided was to install a full length armour plate bolted on to the belly of the vehicle. The time taken between the initial investigations and the installation of the first belly-armour kit in August 1970 was an impressive 12 months and resulted in a significant reduction in injuries. ‘Our positive and rapid response … was a good indication of how the system can react’ said the then Director of Equipment Policy.

The M113A1 has been developed into a series of variants, with a number of these having been subsequently adopted by Australia . These include the M577A1 Armoured Command Post, the M806A1 Armoured Recovery Vehicle Light, the M125A1 81mm Mortar Carrier, and the M548 6-ton Tracked Load Carrier.

Although all the local M113A1 ‘family’ have been built to Australian standards, there are also three variants which are uniquely Australian. These are the Fitters Track, and the two Fire Support vehicles. Both the Fire Support vehicles mounted a 76-mm gun as the main armament. The first had a turret from the Saladin Armoured Car and was built as an interim measure to provide direct fire support to the Cavalry Troop. Eight of the fifteen built were sent to Vietnam during 1971-72. The success of the concept led to the development of the second Fire Support vehicle, also known as the Medium Reconnaissance Vehicle (MRV), in the late 1970s which mounted the turret from the British Scorpion CVR(T) - 48 were built. Both types of Fire Support Vehicle are no longer in service with the MRVs being withdrawn from the early 1990s.