© 2006 All Rights Reserved. Do not distribute or repurpose this work without written permission from the copyright holder(s).
Printed from https://www.damninteresting.com/curio/skipping-bombs-like-stones/
During World War II, German hydroelectric dams were lucrative targets for the Allies. Not only would busting one cut off a major source of power for Germany, but it would also cause destruction through flooding. Plus, it would bring the fight to Germany, rather than defending the Allies’ territory.
Finding a method for destroying the dams, however, proved difficult. Anything but a direct hit with a normal bomb would not do enough damage to break the dam, and bombs were not accurate enough at the time. A bomb powerful enough to destroy a dam via a direct hit would be too heavy for any conventional airplane to carry. On top of that, the dams were protected underwater by torpedo nets, so the only possible way to hit the dam would be against its wall, near the surface of the water. There were no bombs that could get around these problems. The British military found this dilemma unsolvable.
Then along came Barnes Wallis, who invented a bomb that capitalized on the same physics as skipping a stone over water.
Barnes Wallis was working with a team at Vickers in 1941 when he first started to work on a dam busting bomb. In the beginning he ran into the same problems as mentioned above. Eventually he got the idea of skipping a bomb over water from when the Royal Navy used to skip cannonballs across the water to increase their range. A bouncing bomb could glide over the torpedo nets and get close to the bridge – and then once it hits the wall, it could have a delayed explosion so as to allow it to slide a bit underwater to hit the dam at a more damaging location.
Wallis’ original “Highball” design was spherical, but Wallis could not get it to work in time. Instead, the bomb used on the mission was an “Upkeep,” which was cylindrical. During its deployment the bomb would be spun backwards at a high rate (500 rpm), then skipped across the water.
Unfortunately, to achieve the desired skipping stone effect and destroy a dam, the bomb would have to be dropped at a very low altitude (exactly 60 ft), at a precise speed (about 235 mph), and a specific distance from the target (400-450 ft). As such, only the best pilots flew for this strike, and trained to use its special equipment – not only was there such a unique bomb, but they had to be aimed using specialized aiming equipment to calculate the altitude and distance.
The mission, code named Operation Chastise, was executed on May 17, 1943. There were 19 aircraft that flew in three formations to hit six dams; the first two formations attempted to break the key dams, with the third on reserve to take a second shot at any dams that might not have been destroyed the first time around. The results were a success, despite heavy allied casualties (of the 19 planes, only 11 returned). Two of the key targets, the Moehne and Eder dams, were busted. Not only did this cause a loss of power and flooding, but pictures of the busted dams served to heighten the morale of the allied world.
Unfortunately, the destruction of the dams was not as devastating to the Germans as was hoped. Within two months water output was restored and electricity levels returned to full power. Many of the lives lost due to flooding were actually prisoners of war rather than enemies.
After Operation Chastise, the bombing squadron was kept together as a special bombing unit that specialized on precision targets with unique bombs. They would later use other unique Wallis bombs, such as the Tallboy (which was designed to break large concrete structures) and the Grand Slam (a ten ton earthquake bomb which holds the record of the heaviest bomb ever used in conflict). The squadron is still active to this day.
© 2006 All Rights Reserved. Do not distribute or repurpose this work without written permission from the copyright holder(s).
Printed from https://www.damninteresting.com/curio/skipping-bombs-like-stones/
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Now that’s dam interesting.
hee hee
Alan Bellows gets ten points for guessing the first response to this article.
I once considered doing an article on this raid, but from a different angle: the trench battle in Star Wars was an almost exact duplicate of one of these attacks. It was dark, the gun towers on the dam was firing tracers, and they lined up for thier run. Even the auido sounds remarkably the same … Lucas’ only good ideas were mere history in a fancy wrapper.
Jason Bellows said: “I once considered doing an article on this raid, but from a different angle: the trench battle in Star Wars was an almost exact duplicate of one of these attacks. It was dark, the gun towers on the dam was firing tracers, and they lined up for thier run. Even the auido sounds remarkably the same … Lucas’ only good ideas were mere history in a fancy wrapper.”
A lot of the dog fights in Star Wars were cribbed frame-by-frame from WWII combat footage.
I think the coolest part, the aiming system, wasn’t even mentioned. They had two spotlights at different points on the plane. These were placed at very specific angles, and when they lined up the pilot was at the correct height and angle.
Also, the underwater explosive is more powerful than one in air. Similar to clenching a firework in your hand when it blows up instead of letting it rest.
There is a really good movie about this operation. It’s called, surprisingly enough, The Dam Busters.
Hmm… So the bombed bounced. How on earth did they figure out the exact height and speed and stuff for it to bounce? Trial and error?
How about a Damn Interesting article on another strange weapon of war? This one not so successful. . . Check out the double-barreled cannon at http://www.batteryb.com/double-barreled_cannon.html or http://ngeorgia.com/feature/adbc.html. The second barrel wasn’t merely to fire a second shot; a chain was attached between the balls so it would (theoretically) mow down a whole line of men. It wasn’t, to put it lightly, very well executed. Keep up the good work!
Sorry, I couldn’t resist responding to such tiny minded comments, as follows:
poo said: “Hey Chris Lewis, who the fuck holds fireworks in their hand when they are about to go off. “
HEY…Richard Cranium (aka “poo”)…to answer your question…turn your TV on July 5th and find out…that’s who! LOL
I’d like to hear more about that ‘earthquake bomb.’ Oh, and I love french toast. :-)
And here I thought Damn Interesting was a good clean sight to read and learn interesting happenings. Instead, I stumble on the potty mouth article that should have half the comments erased or censored. If you don’t already, maybe you (Damn Interesting) should have a little control over your “subjects.”
BTW it is a damn interesting article. Skipping bombs. Ingenius.
trolls everywhere
Wow, I’ve read a lot of articles on this site and NONE of them have comments like this one. O.o Why are they still there?
Love another viewpoint’s response. I was wondering how they knew “poo’s” real name. Then I realized Richard Cranium is um….hehe, Yeah. Very witty!
Skipping bombs sounds awesome. I played water-polo a few years in high school and skipping balls across the pool was a very common and effective tactic.
Americans were skip bombing targets before Wallis created his dam busting bombs. The AAF was skip bombing shipping in the Pacific and Med. using bombs with depth detonators. The bombs would bounced off the sides of ships then blow up after sinking 20 -30 feet to create a water hammer that caved in the hulls. During the Italy campaign the AAF would skip bombs down railroad tracks in attempts to blow up hidden trains and the massive cannons mounted on rail flat cars (ie: Anzio Annie). It was reported that Erwin Rommel and Alfred Kesselring (Smiling Albert) were traveling in a staff car when the AAF began skip bombing a rail road tunnel up ahead. They stopped and got out to watch the planes make their runs since they never seen anything like that before.
Note to self: Finished.