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Stupid Engineering Mistakes
lee1 writes "Wired has bestowed on us a list of the ten worst engineering mistakes of all time. We have the St. Francis Dam designed by 'self-taught' engineer William Mulholland, which burst and wiped out several towns near LA; the Kansas City Hyatt walkway collapse; the DC-10, and more, but my favorite is the one I'd never heard of: a giant tank of molasses that ruptured in 1919 and sent 'waves of molasses up to 15 feet high' through Boston, killing 21."
The Kansas City Hyatt was a disaster, but it wasn't because of bad design, but actually, "Construction issues led to a subtle but flawed design change that doubled the load on the connection between the fourth floor walkway support beams and the rods carrying the weight of the second floor walkway. This new design could barely handle the dead load weight of the structure itself, much less the weight of the spectators standing on it". The original design would have been safe but what seemed an innocuous change completely changed the dynamics of load bearing, a result easily derived by any first year physics student.
Also, while a "top ten" list is always subjective, I think it'd be instructive to at least include Galloping Gertie as honorable mention, another design which had been identified as flawed. This Tacoma Narrows suspension bridge began swaying wildly as it set up its own harmonic resonance in a typical Puget Sound winter wind storm and eventually ripped apart and collapsed into the Sound. Interestingly the original Galloping Gertie could and would have sustained the fatal winds by strategically placed holes in the beams.
I don't consider disasters as consequences of poor engineering to be especially funny.
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Built on national pride, it's become the world's largest albatross.
A feeling of having made the same mistake before: Deja Foobar
A common theme in half of these is that a small change was made at the last minute.
Lesson of Life: Trust the engineers, they do stuff for a reason
Of course the other half were just poor engineering
Lesson of Life: Never trust the engineers
If this signature is witty enough, maybe somebody will like me.
What on earth were they planning on doing with such a huge stockpile of molasses?!
21 people couldn't avoid the flow of molasses? This seems very strange seeing that molasses is the canonical viscous fluid - slow as molasses in January. 15 foot amplitude, gotta wonder at the wavelength crest to crest...
They forgot the most important one, the one that's screwed the most people by far.
Windows
Osaka built the world's first sports stadium with a movable roof, which malfunctioned shortly after inception, and the company that made it went bankrupt. The roof has been stuck for the past 5 years. Incidentally, the stadium was built on rubbery landfill, so whenever audiences jump up and down during rock concerts, it causes earthquakes in the neighborhood. Osaka also built a new airport on an artificial island that is sinking into the sea, so it may become the world's first underwater airport. Seoul has had various engineering disasters also, including a department store that collapsed and killed hundreds of wealthy housewives.
about engineering disasters, "To Engineer Is Humnan: The Role of Failure in Successful Design". It's worth picking up a copy from amazon/abebooks/etc...
Amazon.com
The moral of this book is that behind every great engineering success is a trail of often ignored (but frequently spectacular) engineering failures. Petroski covers many of the best known examples of well-intentioned but ultimately failed design in action -- the galloping Tacoma Narrows Bridge (which you've probably seen tossing cars willy-nilly in the famous black-and-white footage), the collapse of the Kansas City Hyatt Regency Hotel walkways -- and many lesser known but equally informative examples. The line of reasoning Petroski develops in this book were later formalized into his quasi-Darwinian model of technological evolution in The Evolution of Useful Things, but this book is arguably the more illuminating -- and defintely the more enjoyable -- of these two titles. Highly recommended.
"I'd rather be a lightning rod than a seismometer." -Ken Kesey
this disaster involved a couple morons on a drilling rig in a lake forgetting to carry the two, hitting a mineshaft, and draining the whole lake and part of the gulf of mexico into the mine, along with several ships, etc etc.
VLC FOR MAC IS DYING! IF YOU DEVELOP, PLEASE SAVE IT!!
I used to complain about this too. Then I remembered that Digg and Slashdot exist in the same reality, so there's likely to be some convergence in the content.
And even those accidents the safety defects were quite minor, nothing major that one could claim that it was poorly engineered. Outward opening doors have been used on all aircraft, Douglas was the first one to make one as a baggage door for a production airliner, improper servicing lead to issues with the locks and finally two accidents, the final resulting in a bulkhead failing that sliced the control cables.
United 232 was a result of a failure of imagination, no one imagined that there would be a failure that massive that would severe all there hydraulic lines, even though they weren't placed next to each other (just near each other as they would have be as they have to run to similar areas of the aircraft). The engineer that designed it probably reasoned, that any failure that would result in all three being severed would be large enough that the aircraft would be lost.
http://en.wikipedia.org/wiki/Lake_Peigneur/
c o.html/
Basically, an oil rig, drilling in the middle of the lake, punctured a mineshaft below the lake (mining for salt). The end result was the entire lake draining into the mine below it. Fortunately, nobody was hurt.
From: http://members.tripod.com/~earthdude1/texaco/texa
The water of Lake Peigneur slowly started to turn, eventually forming a giant whirlpool. A large crater developed in the bottom of the lake. It was like someone pulled the stopper out of the bottom of a giant bathtub.
The crater grew larger and larger (it would eventually reach sixty yards in diameter). The water went down the hole faster and faster. The lake had been connected by the Delcambre Canal to the Gulf of Mexico, some twelve miles away. The ever-emptying lake caused the canal to lower by 3.5 feet and to start flowing in reverse. A fifty foot waterfall (the highest ever to exist in the state) formed where the canal water emptied into the crater.
The whirlpool easily sucked up the $5 million Texaco drilling platform, a second drilling rig that was nearby, a tugboat, eleven barges from the canal, a barge loading dock, seventy acres of Jefferson Island and its botanical gardens, parts of greenhouses, a house trailer, trucks, tractors, a parking lot, tons of mud, trees, and who knows what else. A natural gas fire broke out where the Texaco well was being drilled. Let's not forget the estimated 1.5 billion gallons of water that seemed to magically drain down the hole (does the Coriolis effect come into play here?). Of course, there was the great threat of environmental and economical catastrophe.
In 1814 in in London town,
g ht=&
a flood of beer came to drown.
http://www.qi.com/talk/viewtopic.php?t=121&highli
Time flies like an arrow. Fruit flies like a banana.
I can't quite remember, but I seem to recall that the records are scanty on this point -- it may be that the designers of the ship just didn't have the expertise and understanding of buoyancy of later shipwrights, or it may be that there was some kind of kickbacks or other shenanigans that interfered with the building and compromised the design.
When I say "if you look at the ship," though, I am being literal -- because you can. The really interesting thing about the Vasa is that it sank not far from Stockholm harbor, in waters that had a unique mineral consistency. Unlike other parts of the world, for whatever reason the waters in this area were particularly unfavorable to the shipworm. Normally a wooden ship like the Vasa would be eaten up. The Vasa, however, was merely covered with silt at the bottom of the bay, where it lay for hundreds of years.
Eventually -- and again, memory fails me but I believe it was sometime around the 1970s -- the location of the Vasa was discovered and work began to bring it to the surface. Today the entire ship is on display in a museum in Stockholm. The museum building was actually built up around the ship itself. A lot of repair and preservation work had to be done, including plastination of the wood, but it is mostly intact except for the original painting. You can't go onboard, but you can walk around it and view the hull from all sides. It is literally the closest you'll ever get to a 17th century wood-hull sailing vessel -- about five meters away. They've also built a facsimile of the interior decks that you can walk through -- if walking is the word. (Let's just say they made people smaller in those days.)
The museum has salvaged all kinds of other goodies from the ship as well, from cannon to tools to even the bodies of some of the original sailors, all of which are on display. If you get the chance you should check it out -- if you're at all into things nautical, it's a one-of-a-kind experience.
Breakfast served all day!
This one isn't quite on topic, but it keeps with the mood... Lake Peigneur: The Swirling Vortex of Doom
When I think of engineering mistakes, the Cypress Freeway comes to mind. A double-decker freeway built on soil that isn't solid in an earthquake-prone area is a disaster waiting to happen.
The former double-decker section of 880 has since been replaced with a new, single decker structure a bit to the west of the original alignment. The cost of that new, short freeway section was $1.13 billion dollars, more expensive than the costs of LA's Century Freeway (105), IIRC.
From the way things play out, I presume it really means the ten worst reported in the US in the last two centuries. It doesn't even mention the disaster in Japan a few years ago where an entire mega-mall collapsed because they forgot to increase the gague of the beams for the parking level after tweaking the design for the upper levels. I'm pretty sure there were probably some major engineering disasters in building early pyramids and ziggarauts too, not to mention the Roman buildings that didn't survive through the ages.
I agree with a poster above that this shouldn't be listed under "funny" as all of those mistakes cost well over 1,000 people their lives, if I remember the article correctly. But it seemed to focus on the fact that people's lives were lost in just about all of those. I would have placed a number of other engineering mistakes in that list just because of the nature of the mistake.
For example, the bridge (the name of which I can't remember) from the early part of the 20th century that bent and twisted under high wind until it finally just fell apart. Loss of life? I don't believe so, but it was a spectacular destruction.
The Johnstown Flood, perhaps? A lot of people were killed in that flood, and it was caused by engineering of a sort. The dam itself seemed to be stable until a lot of critical components, such as iron rods, were replaced with such highly stable components as dirt and manure, at least according to various web sites and documentaries. Sure, that wasn't a fault of the original design, but the "remodeling" is most likely a very important factor that resulted in the deaths of over 2,200 people.
I found it particularly interesting that the article mentioned how something happened 200 years before Titanic then failed to mention the Titanic itself. Based on the documentaries I've seen, the bolts that were used to hold the steel plates together were cheaply made and severely weakened under the frigid water of the north Atlantic. That was an engineering/design flaw from the beginning.
New Orleans. Oh, yeah! Let's design and build a city with an ocean on one side and a lake on the other and - here's the clincher - we'll make it below sea level! Yeah, baby! Party on! Enough said.
Seriously. I don't know what criteria this person used for the "worst" engineering mistakes, but it's clear to me at least that he really doesn't know what the hell he's talking about.
The Overrated mod is for reversing inappropriate, positive mods, not for voicing disagreement with a post.
Not only did Mullholland build that dam that collapsed, he also built the Los Angeles Aquaduct, that's still bringing water down from the North to supply the city's needs. He's also remembered by Mullholland Drive, along the Santa Monica Mountains. I don't know if he built it, but I do know it was named after him.
Good, inexpensive web hosting
Yeesh... Someone all ready posted a better and more detailed description of the lake. Anyway here is another engineering disaster. The Disney Opera House in California. http://en.wikipedia.org/wiki/Disney_Concert_Hall It was a really nice building. Very ornate and very shiny and cool looking. The problem is that they designed and built Archimedes Death Ray. Certain parts of the building were curved that they were cooking the inside of people's apartments, melting trafic cones, blinding drivers, and setting stuff on fire. The solution was just to sandblast the offending objects but yeesh.
Ooo man the floppy drive is broken. No wait. The computer is just upside down.
>astounding feats of engineering accomplished before computers came along. Now errors seem rampant
Errors were always rampant. Railway bridges used to collapse routinely. Frank Lloyd Wright built buildings that couldn't even keep the rain off, a feat pre-industrial peasants had been managing for thousands of years.
Only the best work has survived until now.
News: Holy Shit! The town molasses has escaped! You have three hours to save yourselves!
Dude: Whoa, sounds pretty bad! I'd better...
News: Next on Six, that Paris Hilton sex tape in full! One hour later... Dude: Whoa, that ruled. I need a beer!
Dude wastes another hour or so drinking and watching pr0n.
Dude forgets about the molasses and goes to bed.
Molasses: I am nearing Dude's house.
Dude: I am now in bed sleeping, unaware of the impending danger.
The molasses eats Dude alive
Dude: What the fuck? Oh shit, the molasses! I totally forgot!
Molasses: And now there is no escape for you!
LOL TRUE!!
Dodge caravan - Engineers were on serious drugs designing that transmission and engine bay.
Pontiac Grand AM 1997-2006 - I want to personally kill the engineer that designed that engine cooling system.
All Delco car radio products 1990-2006 - Those engineers need to be beaten hard with the product they made. Any car that can lose functionality or even not run when you remove the factory radio was designed by a retarted engineer.
I can go on for days just on recent automotive designs and building techniques. Automotive engineers are the most hated on the planet lately because of the incredibly stupid designs they continue to come up with.
And they have done it for decades, Oldmosbile Quad 4 engine, instead of making the engine balanced we put in a harmonic balancer that runs at 4X the engine RPM's.. but not use a system that can handle the incredible RPM's or make sure it stays oiled.
Do not look at laser with remaining good eye.
And really, the humor section? I know being killed by a flood of molasses is novel, how is having a walkway full of people falling on your head funny?
Comment forecast: Bits of genius surrounded by a sea of mediocrity.
"4. Northeastern US power grid, 1965
A single protective relay tripped in Ontario, overloading nearby circuits and causing a cascade of outages that left 30 million homes without power for up to 13 hours. A fragile, redundancy-free design ensured that it would happen eventually. After decades of repairs and upgrades, it happened again in 2003."
Although this point implies that the 2003 outage originated in Ontario as well, a joint U.S. and Canadian investigation found that it originated in Ohio due to several failures of FirstEnergy corporation, among them the failure to keep trees near high voltage power lines adequately trimmed! When the Eastlake generating plant in Ohio went offline during a period of high demand, other high voltage power lines in the area experienced increased demand to pick up the slack. The increased current across these HV lines caused them to sag and short-out when they came into contact with said trees. HV lines heat up and sag as current increases, and this is accounted for in both their design and in guidelines for keeping trees near HV power lines trimmed, which were apparently not adhered to by FirstEnergy.
This wasn't the only thing that FirstEnergy did wrong however. In total, they were found to be in violation of *seven* NERC standards. Although more reliability and redundancy could be built into the North American power grid, blaming the 2003 outage on poor engineering is not accurate. It was FirstEnergy's failure to adhere to standards that precipitated the cascade failure. As such, it would be more accurate to blame greedy corporate management that was too cheap to shell out adequate funds for operation.
For more on this, check out the report found here:
https://reports.energy.gov/BlackoutFinal-Web.pdf
...but I thought "Bridges Are Easy"....
Because the guy honestly didn't care.
s
He (him) fsck'd huge parts of the west out of their water rights to get an ROI out of his investments in L.A.
The damn breaking was terrible PR. I believe it only troubled him because of the fear he would be found liable for the damage.
http://en.wikipedia.org/wiki/California_Water_War
You can still find *giant* chunks of concrete in the flood basin in the east end of the san fernando valley. I was honestly surprised to find them there.
http://www.maxineudall.com/2010/02/should-economists-be-sued-for-malpractice.html
It's very unfair to group the DC-10 with these disasters. McDonnell Douglas was actually very little at fault for the 3-4 accidents that unfortunately occurred right near each other. The most spectacular crash of the American Airlines flight was actually caused by an AA maintenance crew being dumb and cracking the pylon holding the engine. But thanks to the American sensationalistically hostile TV media, the only thing that everyone saw was the engine falling off the wing, which led everyone to assume it was the DC-10's fault, and led to huge cancellations on flights on the actually safe DC-10. It was a good airplane destroyed by bad press and bad luck.
(If any of you have read Airframe by Michael Crichton, you'll know what I'm talking about...from the NYT review of that very good book:
"And, Casey explains, when something goes wrong, a media industry that has grown hostile and shallow with the ascendancy of television always jumps to the wrong conclusion. Why, just look at what happened to the DC-10, ''a good aircraft . . . destroyed by bad press,'' because the crash of an American Airlines flight from Chicago to Los Angeles in May 1979 was misreported and misunderstood. ")
The molasses flood was not an engineering mistake. The basic design of the structure was ok, the disaster is believed to be most likely to been have caused by shoddy contruction techniques and/or overfilling plus pressure buildup due to fermentation of the molasses in the tank.
"I believe in the genocide of front-load washing machine believers."
Dude, this is slashdot, why are you doing laundry?
There: Something at a specific location.
Their: Owned by someone.
Please make sure your english compiles.
How may gave their asses to fill that giant tank?
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No discussion of engineering disasters is complete without mention of PEPCON. First, build a factory 10 miles from Las Vegas. Use it to manufacture ammonium perchlorate -- a component of rocket fuel. Store the stuff in aluminum containers. BTW, aluminum is the other component for the rocket fuel. Then start welding nearby. Oh, and make sure you put the factory on top of a gas main.
http://en.wikipedia.org/wiki/PEPCON_disaster
There's some great footage of it here:
http://www.apechild.com/videos/pepcon.mov
You'll never see a better demonstration of speed-of-sound vs speed-of-light. You see massive explosions and shockwaves (taking out trees and cars) several seconds before you hear them.
dragonhawk@iname.microsoft.com
I do not like Microsoft. Remove them from my email address.
The truly sad aspect of the R-101 disaster is not that it crashed, but that the crash utterly killed any chance that the R-101's sister airship, the R-100, would gain public acceptance.
The two ships were built simultaneously, to the same set of government design specifications. The R-101 was designed by government engineers with an effectively unlimited budget, and no penalties for failing to meet specifications. Because a government agency was building it, the press were treated to frequent and highly colored bulletins about the R-101.
The R-100 was designed by a private firm, under a strict budget, with limited access to design information about the R-101. It was built with much less publicity and launched with no fanfare at all.
The R-100 made a successful trans-Atlantic test flight, was several knots faster than the specification called for, was highly maneuverable, and had a considerable payload capacity. It performed almost flawlessly, and was fairly economical to operate. (The Wikipedia article makes a bit much of the R-100's problems, such as the tail cone collapse; the engineers decided that the tail cone was unnecessary.)
The R-101 was grossly oversized and overweight, poorly stressed, and had been lengthened by some yards at the eleventh hour. Because of pressure to outperform the R-100, it was sent on an intercontinental flight before its local flight tests (which would probably have revealed its weaknesses) were completed. When it crashed, it took with it any chance that the R-100 would be followed up, even though the R-100 was a nearly unqualified success (for a prototype, anyway).
Dig up a copy of Nevil Shute's Slide Rule for an entertaining and sometimes harrowing account of the two rival airships.
I figure by 2030 or so my 6-digit UID will be something to brag about.
I could keep going, but I'm getting really tired of it.
Procrastination -- because good things come to those who wait.
Any list of engineering failures is incomplete without Windows ME.
Navicula hydraulica plena anguilarum est. Omnes castelli tuus nostri sunt. Ed elli avea del cul fatto trombetta.
The deHaviland Comet. Stress concentrations and metal fatigue resulted in the loss of several aircraft.
HMS Titanic. Inadequate watertight compartments (IMHO the bulkheads should've extended higher, and/or been closer together). Also too few lifeboats to accomodate everyone on board.
Hubble telescope. Nno loss of life, just extremely bad press on a very expensive engineering program. 100% avoidable too.
Denver airport luggage system. No loss of life, unless one of the engineers jumped. The automated system was very expensive, late, and never worked correctly. To the point that the airport is using a normal manual labor system and has given up on ever using the automated system. (but is still paying for it)
Chernobyl (sp?) and/or Three Mile Island. Safety equipment, procedures, and training obviously not up to the task.
Any one of several early Soviet nuclear submarine designs. That more of them didn't sink or irradate their crews (more) is a credit to the bravery and dedication of their crews.
The main thing to look for in a "worst engineering mistakes" list would be something that not only seems obviously a bad idea in retrospect... But that should've been recognized as a really bad idea, even with the technology and education levels available at the time.
--- Just another Code-Monkey
... the Windows Registry isn't on that list.
I guess that would be on the SOFTWARE engineering list.
Well, let's confront your misconceptions:
1. It's actually your great-grandmother's suffering you're reliving. You see, the way to wash the sweat and human oils out of clothes was to take the big pot (like a witch's cauldron) and make Clothes Soup over an open fire. So good job on advancing yourself to 1890.
2. If you went back to freshman chemistry, you'd learn that water and oil do not mix. Which means, if you want to get the human soils out of your underwear, and the human sweat/grease out of your clothes, you're going to have to use soap. Water won't do it. Or, if you don't believe me, just stop buying laundry detergent. You do use it, right, hypocrite? FYI: The water is the medium for the soap, and removed soils. It all has to go somewhere - the soap alone won't carry it.
3a. A liberal arts guy, huh? 'Nuff said.
3b. Just for general info, did you ever see what your top-loader does with your Clothes Soup? The paddle in the middle spins a turn clockwise, then a turn counter-clockwise....and so forth. It also has to spin the drum for the spin cycle (you know, the only major moving part on a front-loader). So you have 2 major moving parts, one of which has to support counter-movement. So you're actually on the WRONG END OF THE SIMPLICITY ARGUMENT. Duh.
You do have the efficienty argument down, though. Front-loaders use 40% less water and much less soap, along with being much easier on the actual clothes because there is no paddle-like implement used to pummel your clothes. Gravity and water do that for the front-loader, off that one mono-dirctional moving part.
4. So...you do change the water in your washing machine from time to time, right?
How do you get it out?
Could it be...........a cute little rubber seal? At the bottom of the drum? Under way more standing water pressure than a front-loader sees?
PS: Check into how long Mankind has been making watertight seals. I bet you'll be suprised. We've had time to actually get kinda good at it.
How the hell did your particular brand of idiocy get modded up?
P.S. I understand it's harder to have an orgasm using a horizontal-load washer than a top-loader. Not that this is relevant to the environment or anything. But I like noting it.
I have a MechEng/ Materials dual degree, and one of my later courses was actually a "Metal Failures" course, dedicated to this kind of stuff. Most of it was more complicated. My professor was actually a retired PhD who worked on investigative teams that evaluated accidents like these, and acted as the 'expert witness' for technical information in many cour cases.
We studied this case, as well as many on the list above, in detail. In particular, the box beams in question ran horizontally to support the walkway, while the vertical rod was the support for the end of the box beams. The beams could have been made better, but they were good enough for their design loads.
The problem was that the original design called for one continuous vertical rod, with several levels of walkway hanging from it at different heights. However, due to construction issues, the installation was changed (for the worse) so that separate vertical rods were used. This unfortunately got written approval, and shouldn't have. Instead of the successive loads being applied to the rod, the box beam was then holding the weight of all the floors below it, which it was not designed to do.
Imagine one rope hanging from a ceiling, with 3 people hanging at various heights on the rope. The rope can hold the total weight of the 3 people easily, but each climber needs only enough grip to hold up his own weight. Now imagine due to "construction issues" you can't get one long rope, so you get 2 shorter lengths. Ideally, you'd tie the ropes together to create a nearly identical scenario, but in this case, it's like they tied the bottom rope to the middle guy's ankle, and expected him to hold on with the added weight of the guy below him.
Unfortunately, it was just strong enough to hold a few people, but let go when it was fully loaded.
=
"No fair, you changed the outcome by measuring it!" - Professor Hubert J. Farnsworth
You read it correct. Basically, the wing engine tore away, taking out the hydralics. Sadly, the crew never knew the full state of what was happening. Walt lux (a family friend and my father's co-worker) was a senior captain. He did exactly as he was trained to do. Sadly, without the indicators, they never stood a chance.
I have thought about the fact that my father had one in 61 chance of being the co-pilot on that craft. In fact, airlines pilots (back then, anyways) tend to fly together and would pick the same schedule. Walt and my father flew together a great deal at that time, so it was probably like 1 in 5 chance. Weird to contemplate.
I prefer the "u" in honour as it seems to be missing these days.
Vasa had a complement of 445, of whom it is not clear how many were lost. The HMS Royal George, however, sank just off Spithead on August 29, 1782 in very similar circumstances to the Vasa with the loss of eight hundred, including an admiral of the fleet. An inquest concluded that her loss was due to structural failure. This was one of the worst marittime disasters of all time, and I'm surprised that the loss of the Vasa, and not of the Royal George, is on the list.
The Tacoma Narrows bridge didn't fail due to resonance.
Read that first line again.
It was not resonance, your first year, second year, calculus, dynamics and control systems books all lied to you. Lied. Not truthful. Not correct.
Read: K. Billah and R. Scanlan, "Resonance, Tacoma Narrows Bridge Failure, and Undergraduate Physics, Textbooks;" American Journal of Physics, 1991.
It was not a time dependant thing, therefore, not resonance. The bridge was shaking NOWHERE near its resonant frequencies. The motion of the bridge actually induced "negative damping" . That would sort of be like pulling your parachute and having it drag you to the ground faster and faster as you gain speed. Sounds weird, but totally true. They show in that paper that the bridge under the wind loading becomes a self excited structure and, at a critical wind speed, the eigenvalues of the bridge stucture change sign, causing the bridge to enter an exponentially increasing vibrational state, eventually breaking the bridge down.
I built a cool model of the Tacoma narrows bridge, with controllable air flow, and reproduced this behavior for a college course in experimental design. It was neat to visually watch eigenvalues change in an experiment.
Oh the physics of pulling wool over eyes is so fun. BTW, that "doubling the loading that any physics student could understand" bit in the other posts. Right. Most physics students can't tell you if the box slips downhill or uphill using a free body diagram. Give me a break.
There was a time for a while in the US that everyone and their brother was afraid we'd run out of water, tomorrow (EVERYBODY PANIC). Manufacturers (temporarily) switched production, almost exclusively, to front-load machines to capitalize on that fear. It turns out that the only people afraid enough to actually use the damn things were the people who live in deserts (I'm looking at you southern California). They're the ones that keep foisting abominations like low-flow showerheads on those of us smart enough to live close enough to stable water supplies.
n.b., Just so you know I'm at least half-joking about SoCal, I live in New Orleans, where we occasionally have a little too much water.
Sweet!
http://en.wikipedia.org/wiki/Citigroup_Center
The citgroup building in manhattan. It was well desigend to the standard enginnering principles by its architecht/engineer William LeMessurier. Shortly after its construction, he got a call from a student who asked him about a different type of wind shear, and he assured the student the building was bult to withstand all winds up to like 130mph. After a little thought, he ran the numbers again as the student brought up, and realized that a hurricane might take out the building, and cause a domino effect that would take out most of manhatten. This man actually stepped up and told the buildings owners about the problem, and came up with a plan to fix it. This story seriously restored my faith in humanity, and he is one of the great unknown heroes of our age. All he had to do was keep his mouth shut, and no one could have faulted him, he did everything right. But he still stepped up and said "theres a problem with what i did...."
This is one of the best examples of ethics i have ever seen.
All Troll + "offtopic" mods are meta moderated as "Unfair", because you abused the system.
No, by far the worst engineering mistake was the f-er who designed my date Mary Swansons impossible-to-remove-in-a-car bra clasps in 1989. I was totally going to score that night but the stupid thing wouldn't come off and killed the moment.
The ship sank some 10 to 15 minutes into it's maiden voyage. The exact location was forgotten. It was found as the result of one old fellow who spent years and years looking for it by taking core samples of the bottom of the sound every meter or so. The ship was then dug out of the mud by (now archaic-looking) dive teams, raised and then brought to dry dock where it is today.
IIRC the shipmaster died partway into the construction without a trained or skilled replacement. Unmodified, it would have not been noteworthy and maybe a little under armed. Adding the extra gun deck made the ship too tall and unstable. So to compensate, extra ballast was added, bringing the lowest gun deck about inline with the water.
Before launching, it failed the stability test of the time in which 40 men where to run in unision from one side of the ship to the other 40 times (or something like that). It was launched anyway, sliding nicely into the water, some sails were set and when it rounded the end of the island and caught it first breeze, it tipped and sank.
The sinking roughly co-incided with the end of Sweden as a feared superpower, thought it was only one factor of many.
Beta is broken and the link to classic doesn't work. Stop wasting our time or there won't be anybody left here.
I read the Wikipedia article and found it very interesting:
The vibration had nothing to do with the resonance frequency of the bridge as a structure, but with the fact that it was wind (as opposed to some other form of energy input, e.g. sound) that was exciting the bridge. At a certain wind speed, the bridge enters a positive feedback loop - when the small motion induced by the wind changes the angle of attack in a way that makes the bridge absorb more and more energy from the wind, eventually increasing the amplitude of the oscillation to a point where structural failure occurs.
To make it short: The bridge did not oscillate at one of its resonant frequencies - aerodynamics caused it to vibrate at an entirely different frequency but managed to pump enough mechanical energy into the bridge to break it anyway.
the Kansas City Hyatt walkways weren't a negligent desgin iirc, the problem was in the interpretation of the design. The walkways were suspended by steel rods, which had a nut which supported the Walkway
the design specified that a for each support, a single rod would run vertically down, and each walkway sat on a nut on the rod. The rod was strong enough, each Nut could support a single walkway.
The incorrect interpretation meant that the rod terminated at the first walkway, and a new rod went down to the next level which then terminated, and a third rod then ran to the next walkway down and so on. With 3 walkways suspensed from a nut that was designed to handle the load for 1 walkway it's no surprise it collapsed.
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When a passenger of the foot, hooves in sight, tootel the horn trumpet melodiously
Building it on a fault line.
Check out http://en.wikipedia.org/wiki/Tay_Rail_Bridge. Even in 1879, they couldn't build railway bridges. The Tay Rail Bridge disaster was the reason for compulsory registration of civil engineers, and brought on a large degree of over-engineering in all civil engineering projects. Over-engineering meant that it wouldn't fall down, but it also meant it'd be vastly more expensive to build.
Grab.
the Boston Molassacre?
Serving your airship needs since 1995.
Actually, if you look at those things, the real common theme was that they were designed or modified by people who _weren't_ real engineers. E.g.:
- a dam is built by a "self-taught engineer" who can't even get the foundations right
- a ship design is modified by a king who has no flippin' clue about ship design. He demanded changes like cutting extra portholes right above the water line, loading extra guns and other stuff, and so on. The final design was basically the king's, not the design of a real shipwright.
- a huge container for molasses is designed and its building supervised by a beancounter with _no_ engineering background whatsoever, and whose only concern was getting it built quickly and cheaply.
Etc. Sorry, you can't say "never trust the engineers" when, in fact, those mistakes were made by non-engineers.
Want another common theme? How about ignoring testing or warning signs that it's about to fall apart. E.g.:
- when the dam started to crack, the "self-taught engineer" just ignored it
- the molasses container was (A) never tested, e.g., by filling it with water, and (B) when a worker complained that it leaked heavily, the beancounter just covered the problem by having it painted brown.
- the Vasa, as other posters have noted, was in fact tested before being lanched, but noone had the courage to tell the king that his design doesn't work. In effect, again the warning signs existed, but were effectively ignored.
And the third thing is: don't think those are just historical trivia, because the exact same things happen nowadays with software. Everyone loves to spew the "colleges don't teach engineering" or "it's time programmers started acting like engineers", but some of the most catastrophic mistakes come from people who had _neither_ a CS or engineering college, _nor_ reasonable work experience or training to bring them up to par. I'm not even sneering (mainly) at the actual coders, because lot of those mistakes were from some manager or customer demanding/making some catastrophic change or imposing some impossible deadmark or policy. (Remember the Vasa and the king.)
E.g.,
- a financial institution restates its earnings by 1 _billion_ dollars, because some Excel spreadsheet programmed by a beancounter with _zero_ engineering or programming background... guess what? Mis-calculated by a whole billion dollars.
- a radiotherapy machine, using lead blocks to cover the parts of the patient that shouldn't be irradiated, had a problem using more than IIRC 4 lead blocks. So a doctor takes it upon himself to hack it to use non-rectangular blocks to the same end. The result: the program mis-calculates and some people are given a lethal dose of radiation.
And that's just the spectacular stuff. I'm sure almost everyone has their own stories where someone else's intervention had catastrophic results, even if in less spectacular ways.
A polar bear is a cartesian bear after a coordinate transform.