Terrapin Mk 1

The Terrapin was a British amphibious cargo carrier of the Second World War, often described as Britain's answer to the American DUKW. It was designed by Thornycroft and built by Morris Commercial, and about 500 were produced. Most went to the 79th Armoured Division. They first saw action in autumn 1944, alongside DUKWs, in the operations to open the water approaches to Antwerp along the Scheldt.

Design

The Terrapin was a tall, open vehicle on eight large wheels, all of them driven. Two Ford V8 petrol engines of 85 bhp each sat side by side in the middle of the hull, each driving the four wheels on one side on land and one of the two rear propellers in the water. On firm roads it ran on its centre four wheels, with the front and rear pairs clear of the ground; these came into play on soft beaches, mud banks and slopes. It was rated as a 4-ton carrier, though its payload was split between two holds, one either side of the central engines. This meant it could carry more than a DUKW but not guns or large vehicles.

The Mk 1 weighed about 6.9 tonnes empty and 12 tonnes loaded, measured 7.01 m long and 2.67 m wide, and could reach about 24 km/h on land and 8 km/h in water.

Drawbacks

The design had several weaknesses. If one engine stalled in the water, the other kept driving its propeller and swung the vehicle into a sharp turn. It was slow on land and afloat, and when fully loaded had so little freeboard that it could be swamped in rough water. The driver sat in the middle and had a poor view, made worse by a canvas spray screen over the front hold, so a crew member often had to give directions. The crew sat in the open.

Terrapin Mk 2

Thornycroft produced an improved Terrapin Mk 2. It had a single large hold, a better hull shape, a forward driving position under cover and an overall length of 9.45 m. The war ended before it could go into production, and the plentiful DUKWs made it unnecessary. The Mk 1s were withdrawn after the war.

Survivors and models

A rusting Terrapin, still carrying the Australian Army registration number 149391, was photographed in an Australian yard with the remains of a Tilly utility inside. The archive also holds photographs of a scale model built by Mark Bannerman.