This version never saw combat and was mainly used to train crews who subsequently served in the DD versions of the M4 Sherman, one of a number of unusually modified, special purpose tanks (Hobart's Funnies) that saw action during and after D-Day. Satisfactory sea trials of the Tetrarch took place near Hayling Island and the go-ahead was given to develop a production DD tank based on the Valentine tank. Coincidentally, this was also where trials of a floating version of the British Mark IX tank took place in November 1918.
The first trial of the DD Tetrarch took place in June 1941 in Brent Reservoir (also known as Hendon Reservoir) in North London in front of General Alan Brooke, who was an early enthusiast for the idea. The two forms of propulsion - propeller and tracks - gave rise to the term Duplex Drive ("DD") for such tanks. Straussler was allocated a Tetrarch tank for experimentation and it was fitted with a screen together with a marine propeller that took its drive from the tank's engine. When collapsed, it would not interfere with the tank's mobility or combat effectiveness. The screen covered the top half of the tank and provided buoyancy in the water. This was a folding canvas screen, supported by horizontal metal hoops and vertical rubber tubes filled with compressed air. Instead, Straussler devised an alternative, the flotation screen.
In practice, there would be severe difficulties in transporting by truck enough floats, even collapsed ones, to move a large unit of tanks across a body of water.Īlso, such floats made a tank too wide to launch itself into the sea from an off-shore landing craft, making their use in amphibious landings impractical. The system was unsatisfactory, mainly because of the unwieldy bulk of floats that were big enough to float a tank (each was roughly the size of the tank itself). Trials conducted by the British War Office showed that such a tank, propelled by an outboard motor, 'swam' reasonably well. He used his flotation device experience to develop collapsible floats for Vickers-Armstrong that could be used to construct a pontoon bridge or could be mounted on either side of a light tank to make it amphibious. The engineering solutions he produced tended to be innovative, though sometimes at the expense of practicability. Straussler's work for Vickers-Armstrong, included designing accessories for tanks. and the production vehicles by a new joint company, Alvis-Straussler. The prototypes were built by his own company Straussler Mechanisation Ltd. His work for Alvis involved designing armoured cars such as the Alvis Straussler AC2 and the Alvis Straussler AC3. Throughout the 1930s, he worked with Alvis Cars, Vickers-Armstrong and Hungarian companies on a variety of projects. In February 1933, he became a British citizen.
His work was mainly to do with amphibious, off-road and military vehicles.īetween 19, Straussler ran Folding Boats and Structures Ltd and patented a number of flotation devices, including collapsible ones.
Nicholas Straussler (in Hungarian: Straussler Miklós) (1891–1966) was an engineer mainly remembered for devising the flotation system used by Allied amphibious DD tanks during World War II.īorn in Hungary, he developed a reputation as an innovative automotive engineer before moving to Britain during the interwar period. Tämä käyttövoiman johdosta syntyi nimitys tai termi DD eli Dublex Drive, jota nimeä alettiin käyttää takana olevalla potkurilla varustetuille panssarivaunuille.