16. A Flash of Brilliance
For years, British planners who sought the destruction of the Ruhr dams were faced with a seemingly insoluble problem: accuracy. In theory, a big enough bomb such as the ten-ton British Earthquake Bomb that burrowed deep underground before it exploded, might do the job. It could destroy a dam by seismic waves – a miniature localized earthquake if you would – if it was dropped from 40,000 feet. However, no bomber existed that could carry such a heavy bomb to the required height, then drop it close enough to the targeted dam.
A smaller bomb, if it went off against a dam wall at a sufficient depth, could do the job. However, the Germans were not fools, and their dams were protected by underwater torpedo nets to prevent that. Then British scientist Barnes Wallis finally figured out a solution. Bombers could be sent on a low-level raid to bounce bombs over the water’s surface and over the torpedo nets like a skipping stone until they struck the dam’s wall. When they hit the wall, the bombs would sink down along its surface, and once they reached an optimal preset depth, they would explode. The water would concentrate the blast against the dam, and result in a breach.