13. The Start of a Daring Raid
To figure out the correct distance from which to release Barnes Wallis’ drums to skip their to the dam walls, another ingenious solution was adopted. Each of the target dams had two towers, one on each side. So two stick marks could be placed on a bomber’s windshield. As the bomber flew in, the sticks would visually be to the outside of the dam towers and sandwich them. As the bomber drew nearer, the angle between bomber and towers would grow wider.
As seen from the windshield, the towers would “move” closer to the sticks until, at the correct distance, the sticks and towers lined up. When they did, the explosive drum could be released. Finally, on the night of May 16th, 1943, the raid was ordered to proceed, and nineteen Avro Lancaster heavy bombers of No. 617 Squadron, divided into three formations with separate assignments, took off. They flew along carefully chosen routes in order to avoid known flak concentrations, but as seen below, losses began to mount soon as the bombers reached the European coast.