Dd - Tank Origin

The design was rushed into production. The "DD"—standing for "Duplex Drive"—was born. But the true test was yet to come. On June 6, 1944, at 5:30 AM, off the coast of Normandy, the sea was brutal. Six-foot swells swallowed small craft whole. Many DD tanks, launched too far from shore in the chaos, were swamped and sunk. At Omaha Beach, nearly all of them were lost.

On a cold November morning, Straussler stood on the bank of a placid, man-made lake in Surrey. A Valentine tank, its canvas screen raised like the frill of a startled lizard, sat on the concrete ramp. The crew inside—three nervous volunteers—gave a thumbs up. dd tank origin

For twenty minutes, it churned across the lake. Straussler didn't smile. He just watched, counting the seconds. On the far side, the tank crawled up the muddy bank, lowered its screen, and fired its main gun into an empty field—a triumphant, barking shout. The design was rushed into production

He went back to the drawing board. He replaced the rubber tubes with a system of thirty-six hollow steel pillars. He used stronger, waterproofed canvas treated with wax and linseed oil. The drive mechanism was refined: the tank's own sprockets would turn a pair of propellers mounted at the rear, disconnected from the tracks. On June 6, 1944, at 5:30 AM, off

It worked.