A SPECIAL WEAPON AND A SPECIAL SQUADRON
The problem of how a bomber delivered weapon could breach a major dam was studied by Dr. Barnes Wallis, a distinguished aircraft designer and scientist. Concluding that an attack with a conventional bomb was out of the question, Dr. Barnes developed a 9250 pound cylindrical weapon which, when released at an altitude of sixty feet while rotating backwards at a rate of 500 rpm, would skip along the surface to the dam, roll to a point near the base, and then explode causing shock waves which would crumble the dam.
Recognizing the difficulty of delivering Barnes's weapon, a special squadron (617) led by W/C Guy Gibson was selected. The crews were handpicked by Gibson and began training for low level, night operations. The Lancaster was chosen for the squadron because it was the only aircraft capable of lifting the weapon designed by Dr. Wallis.
THE DAMS RAID (16/17 May, 1943)
With the hope of breaching three dams which were critical to transportation and power generation in the German industrial heartland of the Ruhr Valley, Gibson led the 19 Lancasters of 617 Squadron across the North Sea. At altitudes as low as fifty feet and observing strict radio silence they crossed over Holland and to the German defenders by the height-finding spotlights, Gibson made his run but the bomb exploded 75 yards short of the Mohne Dam. Bow the gunners were fully alert and the second Lancaster was struck on both port engines and its starboard wing set afire. The bomb was released slightly late and bounced over the parapet. Moments later the bomber exploded. Two more Lancs made their runs as the defender's continued their fire but the dam still stood.
As the fifth Lancaster approached, Gibson's and a third bomber took up positions on either side and the three approached the dam together, their turrets pouring fire at the defending gun positions. The bomb was released precisely at the proper point, bounced four times, and rolled down the face of the dam to the proper depth. It exploded and the dam crumbled. The crews of the surviving Lancasters circled to watch the awesome spectacle as thousands of tons of water poured through the shattered dam into the valley below. Guy Gibson received the VC for his actions on this raid.
Later, the Eder Dam was breached. Despite precise attacks by 617's Lancasters the Sorpe Dam was not broken. It was determined later that its construction was somewhat different from the others and the weapons delivered could not possibly have destroyed it.
THE SACRIFICE AND THE AFTERMATH
The Dambusters Raid was probably the most brilliant air attack of the Second World War but the success was achieved at great cost. Eight of the nineteen Lancasters failed to return; 53 aircrew were killed and three had survived to be taken prisoner.
The destruction of the dams caused widespread flooding and interrupted industry, communications, and various utility services. As well, the enemy was forced to redeploy troops and weapons, and to repair the dams. Perhaps the most significant consequence of the raid was the effect it had on the morale of the British and their allies. It provided a timely psychological lift for the allied side which had had its back to the wall for three long years.
Sir Hew Kilner, the new Chairman of Vickers, offered to Wallis a position as Special Director and head of an independent Research Department. It was an anomalous role; there were no terms of reference laid down, nor was there set out with any clarity the relationship between Wallis and his colleagues at Weybridge, but in the looseness of the arrangement Wallis saw his advantage. He could undertake any work which interested him and need not outline his objectives. The work which interested him was the development of variable geometric designs, his objective the design of a wing controlled aerodyne. The
rest of the aircraft world set off in search of higher speeds, longer range and greater pay-load by designing more powerful engines and more stress-resistant frames. Wallis had other ideas.The advisability of securing speed, range and pay-load he recognised, but he was eager to rethink the accepted principles of flight, and in the process of rethinking he groped back over his whole experience as marine engineer, airship builder, aeroplane designer and bomb constructor. From this rethinking came variable wing-span: a mathematical theory not an invention but a theory which Wallis the mathematician could pass on to Wallis the engineer and Wallis the designer. Over forty years, great advances had been made in the theory and practice of the stability and control of aeroplanes, but already the hand of convention was upon aeroplane design. The pioneers had flown on a chair set within the open framework of their craft, their flying-machines made stable by an auxiliary aerofoil