Covenanter Bridgelayer Tank
Jan Hyrman

Despite the remarkable cross-country abilities displayed by tanks in First World War and the inter-war period, it was soon appreciated that some obstacles, such as wide-span ditches, cannot be tackled only with tracks and power.

Simple but working ways how to bridge ditches were introduced already during the First World War, with some tanks carrying fascines, or large bundles of wooden sticks, which were cut away when needed, dropped into the ditch and the tanks could then drive over them. This practice has been used successfully by the British forces for nearly a century now. Assault bridging techniques were being developed in the interwar period, with several designs of carried assault bridges and bridges drawn behind tanks on sledges.

Perhaps the most imminent inter-war design was created by Major Charles Inglis, the bridge designer for the Royal Engineers. A 6.4metre Canal Lock bridge was mounted on the front of a Heavy Mark V Tank in a way which allowed the tank crew to lower the bridge across the ditch or gap using a system of chains and two A-shaped frames. Later a hydraulically operated bridge was introduced, with the jib acting also as a crane if needed. A bridge on idler tracks was also designed ? this could be pushed across a gap by a tank similarly to the later WWII designs.

Despite the fact that all these designs and several others developed in the inter-war period were abandoned, the experience gained allowed Britain to remain at the leading edge of assault bridge design on the brink of the Second World War.

The campaign in France brought a renewed interest in the assault bridging techniques. The importance of armour became obvious as the German 'blitzkrieg' tactics swept across the north of France, with Britain becoming painfully aware of the fact that the associated engineers equipment needed for armoured breakthroughs virtually anywhere in Europe, was not available.
The Covenanter tank, a tank design built by the hundreds (a total of over 1,700 Covenanter tanks were completed) but never used in action, was selected as the basis for a bridgelayer tank which could then be used by Royal Engineers elements within British armoured outfits. Approximately 80 Covenanter Bridgelayers were eventually built based on Covenanter Mk. I and Mk. IV chassis.

Both variants were powered by the Meadows D.A.V. flat 12-cylinder power plant rated at 280 HP, however, the Mk. I and Mk. IV chassis had different radiator, ventilation, fuel cleaning and clutch arrangements.

The detachable No. 1, Scissors Assault Bridge was lowered by means of hydraulic arms and placed on rollers mounted at the front of the folded bridge, then it was unfolded to span any ditch or gap up to 9.14metres (30 feet) wide. The bridge was capable of carrying Class 24 tracked load or any tracked vehicle up to 24 tons of weight, in 1944 a redesigned version was introduced capable of carrying Class 30 tracked load. The power needed for unfolding or folding the bridge was taken from the engine fan drive.  The vehicle had a top speed of about 30 m.p.h. and a range of 100 miles. The armament was limited to one Besa hull machine gun, the maximum thickness of armour was 40mm.

Bridgelayer tanks saw service with Czechoslovak, Polish and Australian troops. The Czechoslovaks used them at Dunkirk during
the siege of the port in 1944-45, the 1st Polish Armoured Division used them while stationed in the United Kingdom, but later surrendered them to the British 9th Armoured Division, when the Poles were transferred to Egypt. The Australians also received a few and used them, according to some sources, in Burma and the Pacific theater (Bougainville).

The Covenanter Bridgelayer design proved to be too vulnerable for the heavy fighting in Italy and the Northwest Europe. The British forces later introduced several more elaborate designs with heavier armour, based mainly on the Churchill chassis. These were most notably the ARK and the Great Eastern designs, with other ideas such as the Bailey bridge mounted on skids or tracks, which was then pushed over the gap by a Churchill tank. None of these designs, however, were used by the Czechoslovaks at Dunkirk.
The Covenanter Bridgelayer Tank deploying
the No. 1, Scissors Bridge.

Source: IWM Collections, photo no. MH 3675
One of the eight Australian Covenanter Bridgelayer Tanks still surviving in Australia.
Photo courtesy of New South Wales Lancers Memorial Museum