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Lancaster bombers flying overhead.

Just how successful was the Dambuster raid?


Of all the military endeavours against Hitler, the Dambusters raid – aka Operation Chastise – holds a privileged place in our collective imagination. Rather than being synonymous with fear and adversity (eg, the desperate escape from Dunkirk), or an existential struggle (eg, when the RAF took on Goering’s Luftwaffe in the Battle of Britain), or mass slaughter (eg, the bloodbath of D-Day), there’s something ‘clean’, even majestic, about the Dambusters.

After all, when we think of the mission, we don’t think of cities on fire, civilians cowering in terror, or soldiers being mown down by machine guns. Instead, we have the far more romantic mental images of plucky, daredevil pilots swooping majestically towards dams in the middle of the night, ready to release the brilliant bouncing bombs which will strike their inert targets with flamboyant panache.

The swashbuckling reputation of the raid was cemented by the 1955 movie The Dam Busters, with its rousing theme music. In the words of historian Max Hastings, author of Chastise: The Dambusters Story 1943, ‘The story seemed to reflect a heroism that was victimless… it carried none of the moral baggage that has become associated with the offensive against Germany’s cities.’

But the reality of Operation Chastise is far thornier than many may realise.

Taking place on the night of 16-17 May 1943, it was intended to wreak havoc on the power plants and factories of the Ruhr Valley – one of Nazi Germany’s industrial heartlands – by knocking out three dams. The famous bouncing bombs were designed to skip over the anti-torpedo nets protecting the dams, detonating at the precise point to cause maximum damage.

To correctly deploy the bombs, the pilots had to fly low over enemy territory. So low, in fact, that some bombers collided with power lines, killing their crewmen. Others were shot down. Of the 133 men involved in the mission, 53 died – a fatality rate of 40%. Of the designated targets, two dams were breached, while a third was only slightly damaged. It was enough to cause catastrophic flooding throughout the region.

An estimated 1,600 civilians and prisoners of war, including female slave labourers from Poland, Russia and Ukraine, drowned in the flooding.

An RAF reconnaissance mission pilot was dispatched to take photos of the devastation. He described ‘what appeared to be a cloud’ which, as he flew closer, was revealed to be the sun reflecting off the flooded landscape. ‘The whole valley of the river was inundated with only patches of high ground and the tops of trees and church steeples showing above the flood,’ he said. ‘I was overcome by the immensity of it.’

The mission was immediately hailed as a resounding, patriotic success. ‘Huns Get a Flood Blitz’ was a typical, triumphant headline back in Britain. But just how much of a strategic success was Operation Chastise?

The immediate damage was indeed significant. Numerous factories were destroyed, with steel, coal and armament production levels greatly diminished and massive loss of hydroelectric output. However, others have suggested this blow simply wasn’t enough to justify the deaths of airmen or, indeed, the mass deaths of civilians in the region.

It’s often forgotten that the Dambusters raid was not ‘victimless’. An estimated 1,600 civilians and prisoners of war, including female slave labourers from Poland, Russia and Ukraine, drowned in the flooding. Even Wing Commander Guy Gibson, the famed leader of the Dambusters immortalised in the movie by matinee idol Richard Todd, later mused how ‘the fact that people… might drown had not occurred to us’, and that ‘no one likes mass slaughter and we did not like being the authors of it’.

One German civilian, Elizabeth Muller, would later recount how she saw ‘trees, roads, gardens’ all swept away before her eyes, while a Russian PoW named Antonio Ivanovna reported how ‘for two to three months we kept finding bodies – they had become fat and swollen with the water. It was awful.’

Dambusters cynics have dubbed it little more than a PR exercise by the RAF to boost British morale during the dark days of the war. They also emphasise that the dams were successfully rebuilt by the Nazis in a matter of months. Even Arthur ‘Bomber’ Harris raised his eyebrows at Chastise, saying ‘I have seen nothing… to show that the effort was worthwhile except as a spectacular operation.’

However, historian James Holland, author of Dam Busters: The Race to Smash the Dams, takes a very different view. Regarding the speedy rebuilding of the dams, Holland asks, ‘If the dams weren’t important, why was the Nazi high command in such a hurry to rebuild them?’

Indeed, it’s been argued that the very act of the rebuilding, with the massive amounts of manpower, money and resources required, weakened the Third Reich’s capabilities elsewhere – especially when it came to strengthening the ‘Atlantic Wall’, their coastal defences against an Allied invasion of Europe.

Mary Stopes Roe, daughter of Barnes Wallis, who designed the bouncing bomb, has made the point that the forces which were ‘put into mending the dams… would have been better employed – from the German point of view – putting in defences on the northern coast of France.’

It’s a point echoed by historians such as James Holland, who puts it very bluntly: ‘Without the dams raid, D-Day would have been considerably harder.’

With its many pilot deaths and scores of drowned innocents, the Dambusters raid may have been a far cry from the romantic legend passed down over the years. But its lasting impact on Hitler’s war machine is ultimately undeniable.