On 16 May 1943, the Royal Air Force launched one of the most famous bombing missions of the Second Wolrd War. The idea was to launch an air attack on a key component of the German industrial complex in the Ruhr Valley. The target was three dams that controlled three-quarters of the Ruhr Valley’s water. By destroying the dams, the Allies hoped to paralyze the industries that relied on the hydro-electric power supplied by the dams. It was also hoped that such a daring raid might contribute to a collapse of the civilian population’s morale.
This this mission has been memorialized in film, literature, and nostalgia and is generally portrayed as a heroic feat. Peter Jackson bought the rights to the story and is reported to be in the process of retelling the event in a new film with a script written by none other than Stephen Fry. Significantly, the film is not intended to be a simple remake of the 1955 film, “The Dambusters.” Instead, the film will explore the event from an entirely modern perspective. Normally historians are leery of Hollywood productions (though, like all sensible people, we do have a huge crush on Stephen Fry, so maybe it wouldn’t be all that bad). In most films, the disclaimer “based on a true story” seems to refer a similarity that goes about as far as saying both the actual history and the film adaptation have people in them. But Dambusters could be a pretty excellent movie--a comedy, even--and Peter Jackson may be just the person to capture the dog’s breakfast that Operation Chastise was… so come close and let the Henchlings tell you the real story of the Dam Busters, starting with...
1. The Mission Almost Didn’t Get Approved
Operation Chastise is exactly the sort of mission that would never get approved today because of the potential for civilian casualties. It’s generally agreed now that we try to keep the guns pointed at the other people who also have guns. However, during the Second World War the debate over the morality of air bombardment was effectively shelved. Many people, including the Air Officer Commanding in Chief of Bomber Command, Arthur Harris, believed that attacking targets with civilian collateral damage was a necessary part of war--and that massive air raids on large German cities would win the war for the Allies. His argument, essentially, was that if you just kept sending enough planes at Germany, even if some got shot down, eventually, some would get through, and break some things, and make people upset. Harris, and a number of other military big-wigs, were convinced that if they broke enough things and made enough people upset, the civilians of war-torn Germany would force Hitler and his cronies to raise the white flag and end the war.
Not everyone was quite at ease as Harris was with this “all’s fair in love and war” thing. The Americans, for example, generally believed that they could use precision missions to take out key aspects of the German war economy, short-circuit Germany’s war production and win the war with fewer casualties all around. It would be a win-win! (Well, unless you’re Germans. Then it’s just... a less-bad tasting loss.)
This actually led to a remarkably effective compromise where the Americans would launch supposedly precision missions by day (you know, because you can see better during the day) and the British would flood the German skies by night when it was harder to defend, which initially made it pretty difficult for German soldiers to, you know, sleep.
Very occasionally some British higher-ups might tug on their moustache and muse that maybe these Americans had some good ideas from time to time and perhaps it would be worth trying this precision-attack thing. Operation Chastise was one of these ideas--but Harris and others who agreed with him fought hard against the plan, derisively referring to them as “panacea attacks,” that took good resources away from his foolproof “if we throw enough baseballs eventually one has to get through” plan.
The premise, then, was that if the British were able to destroy part of Germany’s war economy, say, a series of dams that provided electricity and water for steel manufacturing, the German’s ability to produce war goods would be so damaged that the Allies would win the war. Despite Harris’ and other opposition to the principle of the plan, it was finally approved in early March of 1943.
With the theory approved, that brings us to the next problem….
2. The Near-Impossible Nature of the Mission
The idea to destroy these targets was not new to the British. As early as 1937, two years before the war started, they had acknowledged that strategic advantage of these dams. However, when the opportunity--you know, the Second World War--to make use of this strategic vulnerability arose, it became clear that this would prove more difficult than originally anticipated.
Now, a dam (or three) is a pretty big target. If you stood in front of one, it was about the height of five school buses stacked on top of one another. Unfortunately, from the perspective of an aircraft approaching from above, that 40m of high wall counts for precious little--you’re looking for a thin flat line along with a bunch of other thin flat lines while also flying a plane that predates duct tape. While navigation was fairly spotty in the bests of situations--you know, like in daylight, with no one shooting at you-- it would be extremely difficult to locate the dam when it was night and you were under fire from German fighters and anti-aircraft artillery.
Assuming that the crew found their sliver of a target, they would then have to actually bomb it. Bombing in the Second World War was not the most exact of sciences; with no Call of Duty to practice on, the accuracy rates were quite low. There was a wide margin of error when bombing, in this particular case the margin of error might be five times the size of the dam itself. So the chances of hitting a target that small, in the dark, while being shot at by Germans--maybe not so great.
As if this wasn’t challenging enough, further problem arose with the available technology: primarily the bombs and the aircrafts to transport the bombs. A pretty standard bomb for the era ran about 500lbs. Unfortunately, a 500lb bomb going off against a concrete dam wouldn’t so much as scratch the surface. In order to do any real damage, it was calculated that the bomb would have to be at least 7,500 lbs .
Additionally, when the war began there wasn’t a plane in existence big enough to carry a bomb that big. So we don’t have a bomb big enough, we don’t have a plane that can carry it, and the target’s about as hard to hit as we’re going to get while still getting the mission approved.
This brings us to….
3. The “Red Green” Technology
By 1942, the new Lancaster bomber was just coming onto the scene; it was larger than its predecessors, yet still had speed that could address the attacks by the German fighter aircrafts. With this development, the RAF could now carry and deliver heavier and more powerful bombs (yay, more destruction!) But how to hit the target?
The solution came in the form of a “bouncing” bomb, a.k.a. Upkeep, developed by an engineer at Vickers-Armstrong’s Aviation Section, Barnes Wallis. The bomb was specifically designed to skip along the water, like a stone, until it hit the dam, where it would sink and then detonate like a depth charge. This allowed the bomb to approach the largest surface area of the target, while avoiding defenses like torpedo nets. It also used the water as a natural packing to direct the force of the explosion directly into the wall.
Obviously the “bouncing” bomb would skip across the water in a particular way, but there were still a lot of variables. Wallis needed to ensure the bomb would hit the water and bounce rather than sink, yet still ricochet high enough to clear the German anti-torpedo netting. He also had to make sure the bounce of the arc wouldn’t fall short of the dam, or alternatively clear it entirely and promptly blow up the low-flying plane that had dropped it. After quite a bit of math, Barnes Wallis calculated that the bomb needed to be dropped exactly 425 yards away from the dam, exactly 60 feet from sea level, while the plane was travelling at 222 miles per hour.
This would be a hell of a feat even with modern technology. The Lancaster had a wingspan of 31 metres, which was actually greater than the distance from the underside of the plane to the water at the required altitude. This meant there was hardly any room to turn, even with the Lancaster’s impressive maneuverability. Ensuring this altitude was not a simple task in a Second World War-era plane. The standard altimeter on a Lancaster was useless below 150 feet, so the altitude was determined essentially by eye. Even Guy Gibson, the leader of the raid, almost flew into the lake during a practice run at dusk, when unable to see the difference between the horizon and the surface of the water.
To combat this, the Lancasters were outfitted with two lamps, one just below the nose and another behind the bomb’s casing. These lamps were affixed at an angle such that the beams of the light would line up into a dot when the airplane was at the correct altitude--too high, and the beams wouldn’t touch; too low, and the beams would cross one another and keep going.
This seems like a pretty genius idea until you remember that you have just put two enormous spotlights onto your aircraft while flying in a raid on enemy territory, which you’re doing at night on the premise that maybe they won’t see you coming. The craziness of this is magnified when you remember you are flying so close to the water that if you turned too quickly to avoid gunfire that you are helpfully providing a well-lit target for, you’ve just given the Möhne river one of your plane’s wings as a midnight snack.
Even assuming the pilots could correctly determine their altitude, and that the German gunners failed to shoot a well-lit target flying in a straight line, flying at this low height was incredibly dangerous. While on training for Operation Chastise, two pilots actually damaged their planes by dropping their test-bombs too low and being caught in a huge column of water thrown up after the bomb hit the lake. By the time the attack came five days later, one of these aircraft could not be repaired, and the attacking force was down to 19 aircraft from the originally planned 20. In addition, the Lancaster was never meant to be flown at such a low altitude during an attack, so the aircraft experienced significant turbulence. Nothing like having the individual pieces of your plane vibrate so hard its bolts shear.
Some of the crew needed to sit at an angle to the line of flight which, between that and turbulence from flying 9,940 ft lower than you’re accustomed to, made a number of the men airsick. The airsickness was so bad that some of the men were prescribed sedatives, as though the mission weren’t already complicated enough without the addition of drugs to the mixture.
Having dealt with the issue of altitude, the team now needed a way to quickly calculate distance. This had a surprisingly low-tech solution: using the dam’s twin towers as markers, a sight was constructed using two nails on a triangular frame at an angle that, when held to the eye, would obscure the dam’s towers when the plane reached the correct distance from the dam. Since the bomb had to be dropped 425 ft away from the dam, with the plane travelling at 222 miles per hour, that gave the pilot approximately twelve seconds to get an airplane that was longer than two and a half school buses clear of the dam they had just launched a 7,500lb bomb at.
So you’ve got one guy watching the distance, one guy checking the altitude, one guy guiding the plane, and one guy minding the speed. Guess you need some way to keep these people in contact--maybe like those Star Wars radio helmets, right?
Wrong! Because while the 1940s are famous for a lot of things--Casablanca, elastic-waisted pants, the Slinky--it turns out that sophisticated radio technology wasn’t one of them. Instead, the crews of each of the planes involved in Operation Chastise (or Dambusters, as it’s now called) were literally shouting at each other confirmation of their positions. If all three of these guys didn’t agree, the approach was a wash and the crew would have to circle back and try again.
So, to recap: the Chastise teams had to drop a bomb within a fifty yard radius while flying an airplane half that radius in length at 33 yards per second in speed, dangerously close to the water, lit up like a jack-o-lantern for the Germans to shoot at, in the dark.
And just who were these madmen flying running this show? It’s time to meet...
4. The Rag-Tag Team
Just like you’d want in a movie about a crazy air raid, the RAF required a real ‘crack team’ of pilots and crew to carry out this bombing mission. In the end, 133 men were selected to participate in the raid. Leading them was Wing Commander Guy Gibson, who at the ripe old age of 24, had exhibited “leadership skills and strict discipline.” Although he had participated in over 70 bomber sorties, Gibson accepted the position without knowing what he was getting into. This was the same for the other crew recruited for the mission.
Operation Chastise was top secret, and the men had no idea of their mission and target until hours before the mission itself. While some volunteered for the mission, many were hand-selected by Gibson, who had the authority to choose his crews. In reality, Gibson didn’t really know the men that he selected. Despite what every war move you’ve ever seen would have to believe, the air force is actually a pretty big group of people.
Now when you’re casting a movie--er, mission--like this, you want some people who are highly experienced, and ideally pretty charismatic. You want a bunch of Tom Cruises from Top Gun. As fate would have it, the team wasn’t exactly ‘elite’ from the get-go. The men selected varied greatly in experience. Some, like Gibson, were well seasoned (or as well-seasoned as a guy just old enough to have a Masters’ degree and work at Starbucks can be, zing). For others, however, this would be their first operational sortie. Well…. there’s always beginner’s luck, right?
Of the 133 men Gibson selected, thirty of them were plaid-wearing, axe wielding, maple-syrup blooded Canadians.
The new squadron, temporarily called Squadron X--see, this even sounds like a movie--took base at RAF Scampton and begin training for the incredible mission that awaited them. Well, as much as one can train for a mission when you don’t know what you’re going after, what you’re carrying, or when you’re carrying it.
Welcome to the military, folks.
5. The Tolls
With all of the near-impossible elements of the mission as well as the “Red Green” tech, you can imagine that the mission didn't exactly run smoothly. There were extensive casualties on both sides, and for the attackers the cost of the mission was sharp. Of the 133 men sent on this "suicide mission" (Sutherland, rcaf - ref national post article) 53 of them were killed. Of the 19 aircraft that left RAF Scampton, only 11 returned. Nearly everyone on the planes that crashed was killed. Three airmen were taken as prisoners of war and the Germans were able to capture one of the unexploded bombs. There was considerable fear that the captured bombs would lead to “copy-cat” attacks by the Germans, but Germany never bothered with Rube Goldberg-style attacks on the British.
Additionally, due to the nature of the mission there was extensive collateral damage. Dams require a lot of people to run them, and the Germans had built a PoW camp right underneath one of the three dams that the Allies attacked. When the Mohne dam was breached and flooded the valley, 1020 allied POWs and foreign workers were killed. This was more than the number of German civilians who were killed. But in the excitement of the achievement, there was little attention paid to the cost in civilian lives. Hey, we broke a dam. And it was really hard! Did we mention how hard it was? Did you read that earlier stuff about the tech? It was hard.
In terms of the mission’s tactical goals, the raid was quite successful, as the damage to the industry and infrastructure after the raid and flooding were substantial. By the numbers:
- 2 Dams were breached (so, you know, flooding)
- 1 Dam was damaged (but didn’t burst)
- 11 factories and 92 houses were destroyed
- 971 houses and 32 farms damaged
- 2 822 hectares of farm land were ruined
- 6 300 cows and pigs were killed
- 50 railway and road bridges destroyed
Needless to say, some serious rebuilding was needed. And Germany stepped up--within five months, all the damage the Dambusters had caused was repaired. Historians also like to talk about this thing called “opportunity cost,” which is the cost of stopping Germany from doing other things while it was rebuilding these dams--but that kind of thing is difficult to really quantify.
And though we joke about the movie-like quality of this story--that played a role too. The Allies used the Dambusters story as juicy propaganda for months. Gibson was told when he accepted the mission that he would need to write a book about the experience. The heart of Germany had been struck a decisive blow, wreaking havoc both for the high command's plans and priorities, but also on the civilians whose daily life and living was profoundly affected by the raid. Hitler himself was allegedly furious over the attack, with the Propaganda minister reporting, “The Fuhrer is extremely angry and impatient at the inadequacy of our defensive measures.”
Meanwhile, despite the fact that more than fifty airmen had been lost, many of whom were, remember, supposed to be the RAF’s best, the Allies turned the whole thing into a huge win. Medals and decorations were handed out like candy, 34 being awarded for the heroics exemplified that day. Squadron 617 became revered as the "Dam busters" and is continually commemorated for the gallantry of its crews. So much so that their story may one day stand along the Jackson portfolio with the great epics like Lord of the Rings, District 9, and….. King Kong?
1. Adam Hellicker, “Sir Peter Jacksons’ Dam Busters fails to take off,” Express. December 7, 2014 (http://www.express.co.uk/comment/columnists/adam-helliker/544625/Sir-Peter-Jackson-s-Dam-Busters-film-fails-to-take-off)
2. Sebastian Cox, “Sir Arthur Harris and Some Myths and Controversies of the Bomber Offensive,” Royal Air Force Historical Society Vol. 47 (2010). pp. 6-25.
3. Webster, T. M. “The dam busters raid: success or sideshow?” Air Power History 52/2. (2005) pp.13-25.
4. Webster, p. 12.
7. Webster, pp. 20-21.
8. Webster, p. 17.