“Prototypes of this curious tank were slapped together in the early 1940s amid growing panic in New Zealand over the threat of a Japanese invasion.”

THE GERMANS named some of the their most powerful tanks after ferocious beasts like Tigers and Panthers. Some of Britain and Russia’s heavier fighting machines had their own national wartime leaders for namesakes. Consider the Mk IV A22 Churchill and the IS Joseph Stalin. Illustrious Civil War generals like Sherman, Stuart and Lee were the inspiration for America’s armoured vehicles.

Then there was New Zealand’s only domestically-produced tank of the Second World War. It was known simply as “Bob”… or more accurately, the Bob Semple Tank.

What About Bob?

Named for the 69-year-old Kiwi public works minister who conceived the project, prototypes of the curious fighting vehicle were slapped together in the early 1940s amid growing panic that New Zealand would soon fall prey to a full scale Japanese invasion.

Normally, the government in Wellington would have expected the United Kingdom to supply its former colony with military hardware. But after Britain’s Dunkirk evacuation and with a cross-channel Nazi onslaught looming, London was hard-pressed to spare any heavy weaponry to either New Zealand or Australia.

Desperate for alternatives, Semple figured that domestic manufacturers could produce a home-grown tank using the chassis of a conventional six-ton bulldozer. The final result was an ungainly, cube-like mass of steel that rumbled along at a sluggish 24 km/h (14 mph). The tank’s armour was little more than a few sheets of corrugated iron fashioned into a shroud covering an awkward 10-foot wide, 13-foot long (3.3m x 4.2m) frame. The plates would protected the eight-man crew against small arms fire, but little else. Even worse, the Bob Semple as it was soon dubbed was tragically under gunned — it packed only a half-dozen 7.62-mm Bren guns situated forward, aft and along the sides. In fact, the vehicle was less a tank and more of a slow-moving pill-box.

Fatally Flawed

Aside from the lack of firepower, the Bob Semple tank was plagued by a host of other problems. For starters, a faulty transmission system forced the driver to come to a full stop before shifting gears. In addition, the vibrations generated by the noisy six-cylinder diesel engine rattled the crew and often caused the tank’s guns to jam. Ironically, the inventors of this 26-ton rolling mistake, couldn’t even go “back to the drawing board” so to speak; there were none to go back to. The prototypes were entirely ad hoc designs – meaning they were cobbled together on the go without even a single blueprint.

It’s Ugly But It Gets You There (Sort Of)

Despite its manifest shortcomings, the Bob Semple tank did at least do something well: It lifted the morale of a frightened population.

Although the army refused to actually order any of the machines, Kiwis considered the regrettable reject a symbol of New Zealand’s scrappy resolve to resist and persevere despite long odds.[1] Although it never fired a shot in anger and was never produced in large numbers, the few examples of the Bob Semple tank were proudly exhibited to crowds of cheering civilians. To this day, the vehicle is still fondly remembered among new Zealanders. It even has its own facebook group.