Opperman Scorpion

The Opperman Scorpion was a private-venture British amphibious vehicle built in 1943 by S.E. Opperman of Elstree, an engineering company founded in 1860 for which this was the first wheeled vehicle. It was a diminutive, lightly armoured one-man machine apparently intended for the 1944 invasion beaches, perhaps for clearing beach obstacles, though with no armament and no load space its exact role remains unclear. It has also been described as a design for either a small armoured vehicle or a 30-cwt load carrier.

Design

The Scorpion had eight wheels: three pairs amidships, two of them overlapping, plus a single free-running wheel at each end; only five touched the ground at once on a hard surface. The three central pairs were driven. There was no suspension and no steering gear; the driver steered with a tiller that braked one or other of the large central wheels, and pneumatic tyres had to be used to give any ride at all. Armour was quarter-inch plate, and a circular roof hatch hints that a turret may have been considered. A 24 bhp four-cylinder water-cooled Ford engine gave up to 25 mph (40 km/h) over rough ground, and in water a commercial Anzani outboard motor clamped to a bracket at the rear provided propulsion.

Trials

In trials the Scorpion did well on firm sand and was very good at crossing ditches in which a conventional armoured car (a Dingo was used for comparison) got stuck, but it dug itself in on loose sand and gravel. Afloat it was slow and almost unsteerable, and it could only leave the water up a gentle slope. With no suspension it pitched constantly on firm ground, and its engine frequently overheated. A Mark 2 with better cooling and some suspension was proposed, but the project went no further than the first prototype.