65 Years Ago Today

When I was a kid in the 1960s, my brother was drafted to National Service, as were all young men in the UK those days. He spent some of his time in Germany with the British Army Of the Rhine (BAOR). This was orginally the occupation force after WWII. One of the things he brought back was a wooden wall plaque with pictures showing the immediate aftermath of Operation Chastise which took place 65 years ago today.

Operation Chastise is more famously known as the Dambusters Raid. Its success was both technological and human. Novel solutions had to be employed to destroy the dams which fed the industrial heartland of Nazi Germany. The bombs had to be delivered with the sort of accuracy now expected of GPS guided cruise missiles.

Three vital dams on the Eder River provided the Ruhr industrial area with hydroelectric power and water. Destroying or severely damaging these would decimate the German war production effort. The problem was how to achieve this.

The solution was provided by the designer of the Wellesley and Wellington bombers, Barnes Wallace. He initially proposed a massive conventional high explosive bomb to be dropped from 40,000 feet. Its effect would be much the same as the "bunker buster" bombs of today. The problem was that no existing bomber could carry the 10 ton bomb needed to achieve the "earthquake" effect needed to destroy the dams.

A much smaller charge would destroy the dams if it were place close to the dam wall below the water line. The Nazis realized this and had strung topedo netting to protect them. Barnes Wallace came up with a solution used by Admiral Lord Nelson to extend the range of his ships' cannonballs. He proposed a "bouncing bomb" that would skim over the water in much the same way you can flick a pebble in a pond. On its final bounce, the bomb would hit the dam wall and roll down it to explode. The surrounding water would focus the blast into the masonry.  

To achieve the bounce, Barnes Wallace designed a cylindrical bomb which would be spun before being dropped. The spin combined with the forward speed would provide the "bounce". That last bounce had to be precise. If inaccurate the bomb would either fall short and be caught in the nets or explode ineffectively. Too much energy would send the bomb bouncing over the wall and the blast would not be focussed by the water.

The net effect was that within very close tolerances the bombs had to be dropped from aircraft traveling at a precise speed and height and be released a precise distance from the dams, all of this under anti-aircraft  fire in the dark. Airspeed was comparatively easy to control. Two ingenious solutions solve the rest. To measure the precise height, two angled spotlights were fixed to the aircraft at the front and back. When the two lined up, the plane was at the right height. Distance from the dams were measured in a similar way. The bomb aimer had a simple V shaped wire frame set so that when two towers on the dams lined up with both the target sights at the end of the V arms, the bomb would be released. Once the technical problems were solved it was a case of practicing on runs over similar locations in England's Lake District.

20 modified bombers took off on the raid. The bomb bays had to be removed to accommodate the bomb and its housing/spin mechanism. Armor also had to be taken out to save weight. The raid would demand low flying in the dark to avoid detection as long as possible. This itself had inherent dangers. Two planes were lost after hitting power lines on the outbound leg and one clipped the sea, losing its bomb and returned to base. In all eight aircraft did not return:

"M Mother" - hit by anti-aircraft (AA) fire outbound, shot down while attacking (bomb bounced over dam)

"A Apple" - bomb hit Mohne dam causing small breach, shot down over Holland on return leg.

"Z Zebra" - mine overshot Eder dam and damaged aircraft, shot down over Germany returning.

"B Baker" - crashed after hitting power line on outward journey.

"E Easy" - crashed after hitting power line on outward journey.

"K King" - shot down over Dutch coast outbound.

"S Sugar" - shot down over Holland outbound.

"C Charlie" - shot down over Germany outbound.

Four aircraft's mines hit their targets but with no effect. The mission leader, Guy Gibson's bomb exploded short of the dam and he used his plane to draw AA fire. Those from aircraft callsigns J Johnny and N Nancy hit the Mohne and Eder dams and caused large breaches.

Gibson was to be awarded the highest medal, the Victoria Cross. Of the 133 aircrew on the raid, 53 were killed and 3 became PoWs. The "earthquake" bomb concept was used later in the war on installations like the U-boat pens in France.

In military terms, the raid had limited success. Production was restored fairly quickly thanks to alternatives put in place by the Nazis. Its real success was in terms of showing the Soviets and Americans, who had both relatively recently entered the war, that the RAF could mount significant raids in the heart of Germany.

Today a Lancaster bomber flew low over Derwent reservoir following the path used by those on the wartime training missions.A Spitfire, a Hurricane, two Tornadoes and a Dakota transport plane joined the fly-past. Present at a commemmoration service was the last surviving pilot, Les Munro. The New Zealander had piloted Lancaster callsign W Willie which was damaged by AA fire over the Dutch coast and had to return without attacking its target.

As well as honoring those who took part in the raid, the service also commemorated the at least 1650 killed by the raid and the subsequent flooding. Of these, more than 1000 were prisoners of war, mostly Russian, or forced laborers from work camps.

After the war, the creation of the Iron and Steel Community meant that neither France nor Germany could rebuild their munitions industries in isolation. This was a deliberate move for building peace devised by the Founding Fathers of the EU. In a strange way, the dependence of the US arms industries on materials made in China such as specialist magnets could well mean that war between the two becomes equally impossible, albeit accidentally.