DD or duplex drive tanks, nicknamed " Donald Duck tanks", [1] were a type of amphibious swimming tank developed by the British during the Second World War. The phrase is mostly used for the Duplex Drive variant of the M4 Sherman medium tank, that was used by the Western Allies during and after the Normandy Landings in June 1944.

Mar 24, 2023 · The concept behind the DD tank was either brilliant or preposterous: a standard M4 Sherman tank was retrofitted with a watertight canvas screen that contained numerous inflatable rubber tubes for buoyancy. Crews would raise the screen, launch the DD into the water, and lower the rear-mounted propellers.

For Operation Overlord, 514 tanks were modified with duplex drive kits intended to give the armored vehicles an amphibious capability. This transformed them into the “DD Tank” — the duplex drive tank.

Hobart's Funnies is the nickname given to a number of specialist armoured fighting vehicles derived from tanks operated during the Second World War by units of the 79th Armoured Division of the British Army or by specialists from the Royal Engineers. [1]

With the floating skirt up and the charter propellers in motion, the armored vehicle can reach the speed of four knots in calm weather. This tank, called Duplex Drive, carries the initials D.D. The American and British military quickly call this tank “Donald Duck” in relation to its initials and its capacity to float on the water.

Feb 23, 2023 · Here, an ingenious adaptation of the Sherman medium tank gave rise to the Duplex-Drive (DD) tank, which is credited with helping the Allies secure the invasion beaches on D-Day, and saving many lives in the process. Experimentation with amphibious tanks had taken place since the First World War.

The M4 Sherman DD (Duplex Drive) was an amphibious variant of the M4 Sherman tank used during World War II, specifically designed for the D-Day landings on June 6, 1944. The "DD" stands for "Duplex Drive," referring to its capability to operate both on land and in water.

…famous variation was the “Duplex Drive,” or DD, tank, a Sherman equipped with extendable and collapsible skirts that made it buoyant enough to be launched from a landing craft and make its way to shore under propeller power. The M4 also was …

The final example we present is from a survey of several Sherman duplex drive (DD) tanks (Fig. 13a) sunk approximately 4 km off of Omaha Beach. The Sherman DD tanks were modified into amphibious tanks with the addition of twin propellers and a canvas skirt fitted around the hull to provide flotation (Fig.13b).

Swimming power was provided by small propellers at the stern, which could be engaged and disengaged by the driver, and thus the amphibious vehicle was known as a DD tank (Duplex Drive).