M41as1 Light Tank, 3 APC Sqn, Phuoc Tuy, South Vietnam, 1966

[rickshaw]

M41as1 Light Tank, 3 APC Sqn, Phuoc Tuy, South Vietnam, 1966

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.   It was intended to be air portable and designed for Jungle Warfare.

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.

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.

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).[3] 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.[4] This excluded the University Regiments and the Papua New Guinea Volunteer Rifles which remained unchanged. 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.[3] 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.

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.

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.[3] The Army returned to the tropical establishment in 1965, and many of the CMF battalions were re-established as independent units.

However, before that occurred, the wheels had been set in motion to re-equip the Army with new equipment.  For the Armoured Corps, two key elements were the acquisition of a new Armoured Personnel Carrier (APC) and a Light Tank, both had to be able to easily transported by air.  Trials were conducted for both.  For the APC, the contenders were the British FV432, the French AMX-VTT and the US M113.  The M113 was declared the winner and purchased in large numbers.  The light tank was more problematic with only two contenders, the French AMX-13 and the US M41.  While the M41 Walker Bulldog was out of production, it was decided in the interests of military interoperablity and political considerations that it would be adopted.  In addition, the example of the Royal Australian Marines which already operated the M41 gave the possibility of standardisation between the two services.   The M41 however, was always seen as an interim vehicle until more advanced types, then in development, became available to Army.

While the organisation it was intended for had been abandoned as unweildy, the procurement process had been rushed through and the Light Tank, which had been given priority in order to allow Army to respond to any perceived crises by being able to air lift armour to any trouble spot had resulted in the purchase of 100 M41 tanks.   These were to be allocated to the new Reconnaissance Squadron which was to be formed in the Pentropic Division.  However, instead they were issued to initially the newly formed 1 Cavalry Regiment (which in 1965 was renamed 2 Cav.Rgt. to avoid confusion with 1 Armd. Rgt.) when that organisation was abandoned.   When 3 Armoured Personnel Carrier Squadron was deployed to Vietnam, a troop of M41s was dispatched as well, to "beef up" the Squadron's firepower.  When that Squadron was reformed into 3 Cavalry Regiment, the M41s troop was dissolved and the vehicles were allocated to the Squadron HQ, where they were often used to support individual troops on operations.   The M41 in RAAC service soldiered on until 1978 when it was replaced.









M41 Model

The model is the AFV-Club M41.  It depicts one of the HQ vehicles of B Tp, 3 Cav. Sqn. as deployed to Phuoc Tuy Province, South Vietnam in 1966.  These vehicles gave a considerable boost in firepower to the Cavalry Squadron, being used in the HQ of each Troop in the Squadron in a support role.  In South Vietnam they were used primarily on Convoy Escort and Base Protection duties but occassionally also took part in sweeps against the Viet Cong where the firepower of their 76mm guns with their canister rounds were particularly appreciated.  The modifications were simple, a turret basket with stowage and the substitution of a .30cal MMG for the more normal .50cal HMG.  The Australian Armoured Corps having a preference for increased stowage and an appreciation that the role of the tank commander was to command his vehicle, rather than engage in personal firefights.   As the war progressed, a need for increased stowage was to see another turret basket added to the other side of the turret and the .30cal replaced by the original .50cal.

[kerick]

Nice looking tank! Good story too. I assume the weathering was to look like what a steel vehicle would soon look like in wet tropical conditions?

[rickshaw]

Nice looking tank! Good story too. I assume the weathering was to look like what a steel vehicle would soon look like in wet tropical conditions?

Basically.  South Vietnam is characterised by the thick, red dust which quickly covered vehicles in the dry season and the wet, red mud which covered them in the wet.  To that, I've added some lighter coloured dust as well.   All vehicles were well covered in dust and mud even with regular wash downs, which occurred at Australia's Nui Dat base in Phuoc Tuy province.

[Captain Canada]

Be wild, Red !



Another beauty ! Love the additions, looks great like that. Always nice to see some build pics, gather ideas for future use....thanks !

[NARSES2]

Another nice one 

[zenrat]

Very good.

[Old Wombat]

"Bloody Pongo's, pinchin' our idea!" - Cpl. Clarence "Clarry" Cranfield