D-DAY The Duplex Drive (DD) ‘swimming’ Sherman was an amphibious tank used on all five beaches on D-Day. The duplex drive engine powered propellers in water and tracks on land. The canvas flotation screen gave the tank enough buoyancy to support its weight without having to sacrifice armour or firepower.
Once ashore, the screes were dropped and the tanks became fully operational. This allowed for a quick build-up of armour and provided almost immediate support for the invading infantry forces.
THE ‘CRAB’ FLAIL
The ‘Crab’ was a Sherman tank with a flail (roller and weighted chain) attachment used to clear mines. The flail tank was not a new invention – the Matilda ‘Scorpion’ was used during the Battle of El Alamein in 1942 – but under Hobart’s direction, the ‘Scorpion’ flail was adapted for use on the Sherman. Unlike on the ‘Scorpion’, the flail was powered by the tank’s main engine. The Sherman also retained its 75mm gun, which could be fired as normal when the flail was not in use.
The Churchill AVRE (Armoured Vehicle Royal Engineer) was a modified Churchill tank fitted with a Petard spigot mortar, designed primarily to demolish steel and concrete structures, such as bunkers and gun emplacements. Specialised equipment could be added to the AVRE to enable it to perform other tasks.
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The Churchill AVRE’s main weapon was a 29cm Petard spigot mortar. It fired a 40-pound bomb known as the ‘Flying Dustbin’.
THE ‘BOBBIN’ CARPET LAYER
The ‘Bobbin’ carpet layer was a Churchill AVRE adapted to lay reinforced matting on soft beach surfaces that could not otherwise support the weight of armoured vehicles or other heavy equipment. The matting allowed these vehicles to drive across the difficult terrain.
AVREs were used to transport fascines – large bundles of wooden sticks and other materials used to bridge gaps in the ground. The AVRE would release the fascine into these gaps to create a passable surface. Tank-carried fascines were first used during the First World War to fill trenches that were either too wide or too deep for vehicles to cross.
THE SBG BRIDGE LAYER
This photograph shows an SBG (‘Small Box Girder’) bridge layer on Sword beach on D-Day. This type of AVRE could bridge a 30-foot gap and provide a ramp to scale a wall up to 15 feet high. It was often used in conjunction with fascine, which would provide a softer landing surface when a vehicle dropped from a surmounted wall or other elevated position.
The Armoured Ramp Carrier, also known as the ARK, was a modified Churchill tank with a foldable ramp in place of its turret. It was driven into a gap where it opened its ramps, creating a bridge that other vehicles could cross. Although they were used throughout north-west Europe, they were particularly effective in the later phases of the Italian campaign. This photograph shows two stacked ARKs providing a pathway across the River Senio in 1945.
The CDL (Canal Defence Light) was a Grant tank with a searchlight within the turret. Its main purpose was to provide light during night operations, but it also used to produce a dazzle effect to temporarily blind enemy forces. The CDL had a larger role as night operations became increasingly common in north-west Europe. All of the ‘Funnies’ were developed in secret, but the CDL was the most closely guarded.