15. A Plan to Skip Bombs Like Stones Over the Water
The next problem for British planners to solve was just how to get a bomb to skip on the water’s surface, then sink along the dam’s inner wall after it hit it, instead of simply bouncing back. Barnes Wallis’ solution was a spinning drum filled with explosives. A bomber would fly at a low level as it approached a targeted dam above its reservoir. Once it was at the proper height and distance from the target, it would release the explosive drum, which a motor had set to spin counterclockwise.
The bomber’s speed would propel the drum and cause it to skip over the water’s surface and bounce over the protective underwater torpedo nets. Once it struck the dam, the drum’s counter-rotation, which had been imparted by the motor inside the bomber before the drum’s release, would ensure that it hugged the dam’s wall as it sank. At the proper depth, hydraulic pistols would set it off, and basic physics would take care of the rest. Barnes Wallis’ science was good and his theory was sound. Next, was to find pilots and aircrews with enough skill and courage to conduct what would be an extremely hazardous night time raid.
