The Pentropic organisation was a military organisation used by the Australian Army between 1960 and 1965. It was based on the United States Army's pentomic organisation and involved reorganising most of the Army's combat units into units based on five elements, rather than the previous three or four sub-elements. The organisation proved unsuccessful, and the Army reverted to its previous unit structures in early 1965.
The decision to adopt the Pentropic organisation was driven by a desire to modernise the Army and ensure that Australian units were able to integrate with those of the United States Army. While the US Pentomic organisation had been implemented in 1957 to improve the Army's ability to operate during a nuclear war, the Australian organisation was optimised for limited wars in South East Asia in which there was a chance that nuclear weapons might be used. Both structures were designed to facilitate independent operations by the sub-units of divisions. The Australian Pentropic division was intended to be air portable, capable of fighting in a limited war and capable of conducting anti-guerrilla operations. [2]
The key element of the Pentropic organisation was the reorganisation of divisions into five combined arms battle groups. These battle groups consisted of an infantry battalion, field artillery regiment, engineer field squadron and other combat and logistic elements, including armoured, aviation and armoured personnel carrier units as required. These battle groups would be commanded by the commanding officer of their infantry battalion and report directly to the headquarters of the division as brigade headquarters were abolished as part of the reorganisation. [3]
When the Pentropic organisation was implemented in 1960 the Australian Army was reorganised from three divisions organised on what was called the Tropical establishment (the 1st, 2nd and 3rd divisions) into two Pentropic divisions (the 1st and 3rd). [4] While two of the Army's three regular infantry battalions were expanded into the new large Pentropic battalions, the 30 reserve Citizens Military Force (CMF) battalions were merged into just nine battalions. [5] This excluded the University Regiments and the Papua New Guinea Volunteer Rifles which remained unchanged. [6] There was a similar effect on the other CMF units, with most being merged into new, larger units. The other regular infantry battalion remained on the previous tropical establishment as it formed part of the 28th Commonwealth Brigade in Malaysia. [4] As part of this reorganisation the Army replaced its outdated weapons with more modern weapons, most of which were supplied from the United States. It was believed that these new weapons would further improve the Army's combat power and the ability of sub-units to operate independently. [4]
The Pentropic organisation was trialled during exercises in 1962 and 1963. These exercises revealed that the battle groups' command and control arrangements were unsatisfactory, as battalion headquarters were too small to command such large units in combat situations. While the large Pentropic infantry battalions were found to have some operational advantages over the old tropical establishment battalions, the divisions' large number of vehicles resulted in traffic jams when operating in tropical conditions. [3]
The experience gained from exercises and changes in Australia's strategic environment led to the decision to move away from the Pentropic organisation in 1964. During the early 1960s a number of small counter-insurgency wars broke out in South East Asia, and the large Pentropic infantry battalions were ill-suited to these sorts of operations. As the US Army had abandoned its pentomic structure in 1962 and the British Army remained on the tropical establishment, the Australian Army was unable to provide forces which were suited for the forms of warfare it was likely to experience or which were organised along the same lines as units from Australia's main allies. In addition, concentrating the Army's limited manpower into a small number of large battalions was found to be undesirable as it reduced the number of deployable units in the Army. As a result of these factors the Australian Government decided to return the Army to the tropical establishment in November 1964 as part of a wide-ranging package of reforms to the Australian military, which included increasing the size of the Army. [4] The Army returned to the tropical establishment in 1965, and many of the CMF battalions were re-established as independent units. [8]
The main elements of the Pentropic divisions were: [9]
The 3rd Division was an infantry division of the Australian Army. Existing during various periods between 1916 and 1991, it is considered the "longest serving Australian Army division". It was first formed during World War I, as an infantry division of the Australian Imperial Force and saw service on the Western Front in France and Belgium. During this time it fought major battles at Messines, Broodseinde Ridge, Passchendaele, Amiens, and the St Quentin Canal.
The Australian Army Reserve is a collective name given to the reserve units of the Australian Army. Since the Federation of Australia in 1901, the reserve military force has been known by many names, including the Citizens Forces, the Citizen Military Forces, the Militia and, unofficially, the Australian Military Forces. In 1980, however, the current name—Australian Army Reserve—was officially adopted, and it now consists of a number of components based around the level of commitment and training obligation that its members are required to meet.
The Royal Australian Regiment (RAR) is the parent administrative regiment for regular infantry battalions of the Australian Army and is the senior infantry regiment of the Royal Australian Infantry Corps. It was originally formed in 1948 as a three battalion regiment; however, since then its size has fluctuated as battalions have been raised, amalgamated or disbanded in accordance with the Australian government's strategic requirements. Currently, the regiment consists of seven battalions and has fulfilled various roles including those of light, parachute, motorised and mechanised infantry. Throughout its existence, units of the Royal Australian Regiment have deployed on operations in Japan, Korea, Malaya, Borneo, Vietnam, Somalia, Rwanda, Cambodia, East Timor, the Solomon Islands, Iraq and Afghanistan.
The 25th/49th Battalion, Royal Queensland Regiment is a Reserve light infantry battalion in the Australian Army, based in the state of Queensland. Although it was officially formed in 1997, the unit can trace its lineage back to units that were formed in 1875 as part of the colonial defence force of the state of Queensland. Additionally, in order to preserve the honours and traditions of the Australian Imperial Force, the battalion is the custodian of the battle honours awarded to two battalions that were formed for service during World War I. Following the end of the war, these units were raised again as militia units. During World War II, these battalions were called upon to participate in the fighting in the Pacific. Following the end of the war, these units were disbanded although they were later re-raised as part of the Citizen Military Forces, which was the forerunner to the Australian Army Reserve that exists today.
1st Brigade is a combined arms formation of the Australian Army. Formed in 1903 as a militia formation based in New South Wales, it was reconstituted as part of the Australian Imperial Force in 1914 for service during World War I, the brigade fought at Gallipoli and on the Western Front before being disbanded in mid-1919. In 1921, the 1st Brigade was re-raised as a unit of Australia's part-time military forces, based in New South Wales. During World War II the brigade undertook defensive duties before being disbanded. In 1948, it was re-raised as an integral part of the Australian Regular Army. Currently the brigade is based at Robertson Barracks in Darwin and at RAAF Base Edinburgh near Adelaide, South Australia. It is the first of the Australian Army brigades to be re-organised as a combat brigade under Plan Beersheba.
The Jungle division was a military organisation adopted in early 1943 by the Australian Army during the Second World War. This organisation was a much lighter version of the standard British-pattern infantry division used during previous campaigns in the deserts of the Mediterranean and Middle East Theatre fighting the Germans and Italians in 1940 and 1941 and was optimised to meet the needs of jungle warfare against the Japanese in the South West Pacific Area. Jungle divisions were smaller and had fewer heavy weapons, vehicles and support units than the British-pattern division previously used and had an establishment of just 13,118 men, approximately 4,000 fewer than a standard division. The bulk of the reduction occurred among the administrative, transport and artillery units. The conditions that prevailed in the South West Pacific Area led the Australian Army to initially convert five infantry divisions to Jungle divisions, although this was later increased to six. Divisions converted to the jungle organisation included three Militia divisions: the 3rd, 5th and 11th and the three Australian Imperial Force (AIF) divisions: the 6th, 7th, 9th. Despite some modifications, this re-organisation proved successful during later Australian operations in New Guinea, New Britain, Bougainville, Aitape-Wewak and Borneo in 1944–1945.
The 3rd Battalion was an infantry battalion of the Australian Army. Originally raised as part of the First Australian Imperial Force for service during World War I, the battalion formed part of the 1st Brigade, attached to the 1st Division. It was formed shortly after the war broke out and was among the first Australian units to be sent overseas, arriving in Egypt in December 1914. In April 1915 the battalion participated in the Landing at Anzac Cove, coming ashore in the second and third waves. In December 1915 the 3rd Battalion was evacuated from the Gallipoli peninsula and withdrawn to Egypt again, where it took part in the defence of the Suez Canal before being sent to France to fight on the Western Front in March 1916. For the next two and a half years the unit would serve in the trenches in France and Belgium and would take part in many of the major battles fought during that time. In May 1919, following the end of the war, the battalion was disbanded and its personnel repatriated back to Australia.
The 4th Battalion was an infantry battalion of the Australian Army. Originally raised as part of the First Australian Imperial Force during the First World War, the battalion formed part of the 1st Brigade, attached to the 1st Division. During the war the battalion fought at Gallipoli and in the trenches on the Western Front, before being disbanded in 1919. In 1921, the battalion was re-raised as a militia unit and designated as the "4th Battalion ", adopting the designation of the Australian Rifles militia unit from which many of the battalion's recruits had come during the war. In 1930, the battalion was amalgamated with the 3rd Battalion and they remained linked until 1936, when they were delinked.
The 6th Battalion was an infantry battalion of the Australian Army. Originally formed in 1914 for service during the First World War, the battalion fought at Gallipoli and on the Western Front. The battalion was disbanded in 1919 but was re-raised in 1921 as part of the Citizens Force, and adopted the title of "Royal Melbourne Regiment" in 1935. The battalion did not serve overseas during the Second World War and was eventually disbanded in 1944. It was re-raised in 1948 and remained in existence until 1960 when it was absorbed into the Royal Victoria Regiment. Today its honours and traditions are maintained by the 5th/6th Battalion, Royal Victoria Regiment.
The 4th Brigade is a brigade-level formation of the Australian Army. Originally formed in 1912 as a Militia formation, the brigade was re-raised for service during World War I, elements of the brigade served at Gallipoli and in the trenches on the Western Front before being disbanded in 1919. In 1921, the brigade was re-raised as a unit of Australia's part-time military forces, based in the state of Victoria. During World War II the brigade served in the New Guinea and New Britain campaigns. Following the war, the brigade formed part of the 3rd Division, however, it was later reallocated to the 2nd Division, where it serves as a Reserve combined-arms formation including units and personnel from all corps of the Army including armoured, infantry, artillery, engineers, signals and ordnance.
Pentomic was a structure for infantry and airborne divisions adopted by the US Army between 1957 and 1963, in response to the potential use of tactical nuclear weapons, on future battlefields. It was intended that the five subordinate units, which were often referred to as battle groups, would be able to deploy and engage in operations more rapidly than conventional brigades, whilst also having greater offensive capabilities than conventional battalions.
The Victorian Scottish Regiment (VSR) was an infantry regiment of the Australian Army. Formed in 1898 as a volunteer unit of the colonial Victorian Military Forces, the unit went through a number of changes in name over the course of its 62-year history. During World War I many of its members volunteered for overseas service and saw action at Gallipoli and on the Western Front in France. Following the end of the war, the regiment was reorganised to perpetuate the honours of the 5th Battalion, AIF. During World War II the battalion was employed on garrison duties in Australia, although many of its members volunteered for overseas service and fought in campaigns in North Africa, the Middle East and New Guinea. Following the war, the battalion was re-raised as part of the Citizen Military Forces and undertook the training of national servicemen until 1960 when the unit was disbanded and absorbed into the 1st Battalion, Royal Victoria Regiment. Today, the regiment's traditions are maintained by 'B' Company, 5th/6th Battalion, Royal Victoria Regiment.
5th Brigade is a brigade of the Australian Army. Originally raised as a militia formation in 1912, the 5th Brigade was re-raised for overseas service in 1915 as part of the Australian Imperial Force during the First World War. The brigade then served during the Gallipoli Campaign and on the Western Front. During the inter-war years, it was re-raised as a part-time formation as part of Citizens Military Force. It undertook garrison duties in Australia during the Second World War, but was not deployed overseas before being disbanded in 1944. Following the war, the brigade was re-raised in 1948 once again and it is currently a Reserve combined arms formation based in New South Wales and forms part of the 2nd Division.
The 13th Battalion was an infantry battalion of the Australian Army. Originally raised for the 1st Australian Imperial Force during the First World War, it was formed just six weeks after the start of the war. Along with the 14th, 15th and 16th Battalions which were recruited from New South Wales, it formed the 4th Brigade. The battalion saw service initially at Gallipoli before being transferred to France in 1916. For the next two years it fought in the trenches of the Western Front, earning numerous battle honours in the process.
The 45th Battalion was an infantry battalion of the Australian Army. Raised for service during World War I, the battalion served in the trenches on the Western Front in France and Belgium from mid-1916 until the end of hostilities in November 1918. Following this, it was disbanded in May 1919. Later, in 1921, the battalion was re-raised as a part-time unit of the Citizens Force, based in New South Wales. The battalion remained on the order of battle until 1942, when it was merged with the 1st Battalion as part of a force reduction that was undertaken at that time in response to an over mobilisation of the Australian military in the early part of World War II. In 1948, the battalion was re-raised again and remained on the order of battle until 1960 when it was absorbed into the Royal New South Wales Regiment.
The 6th Combat Support Brigade is an Australian Army brigade. First formed in 1912 as a Militia formation to provide training under the compulsory training scheme, the brigade was re-raised during the First World War as an infantry unit of the all volunteer Australian Imperial Force. It subsequently served at Gallipoli and in France and Belgium on the Western Front. In the 1920s, as part of a reorganisation of the Australian Army, it became part of the 3rd Military District of the Citizens Military Force, encompassing units from Victoria and South Australia. In 1991, it became part of the Ready Reserve Scheme, based at Enoggera Barracks, in Brisbane, Queensland, before being disbanded in 1996 when the scheme was discontinued. The brigade was re-raised on 1 March 2010 to oversee the Army's command support and intelligence, surveillance, target acquisition and reconnaissance units.
Lieutenant General Sir Alwyn Ragnar Garrett, KBE, CB was a senior commander in the Australian Army. He served as Chief of the General Staff (CGS) from 1958 to 1960.
The 47th Battalion was an infantry battalion of the Australian Army. It was originally raised in 1916 for service during the First World War. The battalion then took part in the fighting in the trenches of the Western Front in France and Belgium, before being disbanded in early 1918 to provide reinforcements for other Australian units that were suffering from a manpower shortage following the German spring offensive. In 1921, it was re-raised as a part-time unit of the Citizens Force, which later became the Militia. During this time it was based in south-east Queensland and in 1927 it became known as the "Wide Bay Regiment". During the Second World War the 47th Battalion took part in fighting in New Guinea and Bougainville, before being disbanded again in January 1946. Later, the battalion was re-raised before eventually being subsumed into the Royal Queensland Regiment in 1960.
The 30th Battalion was an infantry battalion of the Australian Army. It was originally formed in 1915 during the First World War as part of the all-volunteer Australian Imperial Force (AIF) and saw service on the Western Front before being disbanded in 1919. It was re-raised in 1921 but was later amalgamated with the 51st Battalion in 1930. In 1935 the two battalions were delinked and the 30th re-raised in its own right. During the Second World War it undertook garrison duties in Australia before undertaking active service in New Guinea in 1944–1945. After the war, it was disbanded in early 1946. In 1948, the battalion was re-raised again and remained on the order of battle until 1960 when it was absorbed into the Royal New South Wales Regiment.
The Australian Army has operated M113 armoured personnel carriers since 1964. An initial pair of M113s was purchased for trials purposes in 1962. Either 817 or 840 were acquired by 1979, comprising nine different variants. A long-running modernisation program that commenced in the 1990s resulted in 431 M113s being upgraded between 2007 and 2012. All of the upgraded M113s remain in service as of 2020.