Destroying a dam can’t be achieved by conventional bombing (since the main strength of the dam is at the base), but Barnes Wallis, an English engineer, invented a different type of bomb – the ‘bouncing’ bomb.
This bomb, shaped like an oil drum, was released from the plane at low altitude, and bounced across the water, similar to a pebble skimming the surface. When it reached the wall of the dam, it sank and then exploded, causing the base of the dam wall to be breached.
617 Squadron was formed in early 1943 for the specific task of destroying the dams, and the crew practised low-level flying over water, particularly over the Derwent dam in Derbyshire. This shows a Lancaster bomber flying over the dam to commemorate the 50th anniversary of the Dambusters in 1993.
I first visited the Mohne Dam about 15 years ago, and then returned in 2003, on the 60th anniversary of the raid. It was a weird experience, standing on the dam at 12.28am, the exact time when the first Lancaster flew at very low level (only 60 feet) above the reservoir towards the dam. The aircraft took it in turns to drop their bomb (each plane could only carry one bomb) , and the 5th one finally breached the dam wall, causing a torrent of water to cascade down the valley, destroying everything in its path. The section of the dam that was later repaired is visible as the darker area in the middle of the dam in this photo.
|The Mohne Dam after the raid|
We also visited the Eder dam, which was breached by another section of the squadron. The area where the sluice gates are missing shows where the dam was destroyed and later rebuilt. The Eder is surrounded by hills, and the pilots had to climb very steeply after releasing the bomb so as to avoid crashing into the hillsides.
The third dam attacked that same night was the Sorpe Dam, which had a different construction, and was attacked by flying along its crest. It was damaged by not destroyed.
Nineteen bombers took part in the raid, eight did not return. Six were shot down either on the outward or return flights, or over the target; two crashed after hitting power cables while low-flying over Germany. In all, 53 of the 133 crew members were killed.
At Woodhall Spa, in Lincolnshire, not far from the Scampton RAF base where 617 Squadron was based, a memorial was erected in memory of the Dambusters.