The unit later called the Wombat Battalion started not as an official battalion but as a group of engineers, railway workers, dockyard welders, and AIF veterans in the heavy workshops of Williamstown railway yards and nearby docks on Port Phillip Bay during the last months of World War II.

The original requirement was based on practicality. Australian forces in New Guinea, Borneo, and nearby islands faced terrain where regular tanks didn’t work, and pack transport was unreliable. Roads turned to mud in the monsoon, bridges fell apart, and vehicles broke down due to humidity. Infantry could move forward, but slowly and without the necessary fire support against well-defended Japanese positions and new threats that appeared in the last year of the war.

A proposal from the Army’s Directorate of Mechanical Engineering in late 1945 suggested creating a medium mechanized bush vehicle that could travel in areas where wheeled and tracked vehicles could not. The idea was straightforward: a walking machine that could step over logs, cross streams, and climb rough terrains while carrying armor and weapons to support infantry patrols. This proposal could have stayed theoretical if it hadn’t found an unexpected place in the workshops of Williamstown.

The Williamstown railway yards had spent the war years fixing locomotives and making heavy transport parts for the nearby dockyard. By 1946, as wartime contracts decreased, the workshops still had skilled workers and heavy machinery but didn’t have a clear plan. Several returning servicemen, who were fitters from armoured and engineering units, started to experiment with load-bearing frames made from surplus steel plates, locomotive suspension parts, and hydraulic components taken from old industrial equipment.

The first prototype, called “Quadruped Load Carrier No.1,” was basic. It had a central body on four legs powered by modified hydraulic pistons and electric motors using a petrol generator. Movement was slow and clumsy, but it could travel over terrain where trucks or Bren carriers couldn’t go. More importantly, it could carry heavy loads. When equipped with makeshift armor and a mount for a Vickers gun, it was able to provide moving fire support while advancing with soldiers.

News of the experiment got to Army leaders through informal means, mainly from officers who had worked with the same men now in the yard. By mid-1947, a small team from the Army Design Establishment was sent to watch the trials. Their report called the machine “not practical for regular warfare but possibly useful for operations in rough or thickly vegetated areas.” The funding was limited but enough to officially start the project under the vague name Bush Mobility Experimental Section.

Over the next eighteen months, development increased. The Williamstown workshops adapted railway techniques for armour construction, creating hull sections that could be put together without special casting. Locomotive gears were changed to move the legs. Cooling systems were made to work in humid conditions. The machines became more reliable, stable, and, of course, more heavily armed.

Veterans from engineering and armored units created a test group. They learned to operate and maintain the walkers in their original environment, surrounded by steel frames, oil drums, and the noise of railway repair work. The crews nicknamed the machines “Wombats” for their short, heavily armored look and their slow, stubborn nature—hard to start, tough to stop, and more likely to push through obstacles than go around them.

By 1948, three working prototypes were ready. They were moved north for tests in tropical conditions with infantry units to assess their value for patrol support and perimeter defense. Reports were cautiously positive. The walkers were slow and needed regular maintenance, but they could transport heavy weapons over terrain that other vehicles couldn’t handle. They were especially useful in defense, helping to secure patrol bases and provide higher fire support above thick vegetation.

In response, Army leaders approved the creation of a permanent unit: the 3rd Experimental Bush Warfare Group (Mechanised). Members were selected from engineering corps, armoured units, and infantry battalions with jungle experience. Training took place at Williamstown, where railway yards were converted into an armoured depot. Walkers were next to locomotives being fixed, and armour plates were cut using the same machines that made rail parts.

The unit’s informal title, Wombat Battalion, was officially used because there was no better name agreed upon. The motto, “Eats Roots and Leaves,” started as a joke about the wombat’s diet and the machines’ ability to clear paths through the jungle. It was later put on unit insignia and banners made for morale, not regulations.

Operational doctrine stressed teamwork with infantry instead of acting alone. The walkers were meant to move with patrols, offer fire support, and act as mobile strongpoints in areas where artillery and traditional armor couldn’t go. Maintenance was demanding, needing a dedicated crew of mechanics for each machine alongside its operators. This led to the battalion not reaching large numbers; instead, it operated as a specialized unit deployed where the terrain and situation warranted it. This doctrine demanded heavy armaments and the Taipan Projector Cannon was developed from a captured German tank.

By the early 1949, the Wombat Battalion was both a test and a symbol. Its machines clearly came from industrial sources, showing signs of railway and dockyard work. However, they reflected a unique Australian style of mechanised warfare: practical, makeshift, and influenced by available skills and materials rather than just official plans.

From the workshops of Williamstown to the jungles beyond the mainland, the battalion’s history was connected to its origin. The railway yards kept making replacement parts and new hulls long after other wartime industries had shut down or changed. Each machine showed, in riveted steel and welded plate, the mark of the yard where it was made—an industrial heritage as noticeable as any regimental tradition.

Konflict 47 rules
Unit Type: Medium Walker (4 Legs)
Standard Weapons: 1x Turret-mounted Taipan Projector Cannon (counts as a Schwerefeld Projektor) Regular: 255
1x Forward-facing, Hull-mounted MMG Veteran: 306
Movement Rate: Up to 6″ . Advance Run: 6″–12″
Damage Value: 9+
Quality: Regular 255pts / Veteran 306
Morale Value: 9/10
SPECIAL RULES
•Multi-legged/Slow
Rift Dice: 1 Gravity Pulse Weapon

The model is the Australian Heavy Quad Bush Walker WW2 from Kyoushuneko Miniatures, and the drawings were done by Chattie. Photos by the author.