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Ten Technology Disasters
Ant writes "What do a 17th-century Swedish warship, an opulent Chicago theater and a Kansas City hotel "skyway" have in common? All met catastrophic ends and they have important lessons to teach today's innovators."
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I only hope Microsoft is so lucky.
"The United States has no right, no desire, and no intention to impose our form of government on anyone else." - Bush 05
... Submitting your page to Slashdot, technology disaster number 11 :)
"Dancing is the vertical expression of a horizontal desire" --Robert Frost
Slashcode is a technology disaster.
yatta! yatta! yatta! iz zo eeeazee. happy go la-cky.
Windows 3.1
Windows 3.11 for workgroup
Windows NT 3.51
Windows 95
Windows NT 4.0
Windows 98
Windows ME
Windows 2000
Windows XP
Windows XP professional
the mess of spaghetti code running slashdot...see today's downtime as exhibit z.
What about the turd known as Slashcode? While not rivalling Titanic, it is a disaster.
C - A language that combines the speed of assembly with the ease of use of assembly.
Linux programmers trying to build a usable operating system.
A ship blew up in the port. Oops.
If tits were wings it'd be flying around.
The engineering undergraduate program at Queens University actually has a disasters course as one of the non-technical electives. Basically, it involves dividing the class up into small teams, each of which then picks an engineering disaster to analyse in great detail. Presentations and written reports are submitted at the end of the semester.
:-)
Supposedly this engenders a greater sense of responsibility into the engineers to be. I think it worked it for me
Websurfing done Right! StumbleUpon
augment your senses: http://sensebridge.net/
Linux
OpenBSD
FreeBSD
NetBSD
*BSD
HURD
and anything else infected with the GPL!
C - A language that combines the speed of assembly with the ease of use of assembly.
Well, technology can conceivably be perceived as the root of all evil. I mean, this isn't necessarily how I feel... but technology inherently leads to disaster.
Nuclear power -> nuclear weapons -> nuclear war.
Airplanes -> bombing -> death.
Boats -> armada -> war. death. famine. pestilence.
See what I mean? What's next bioengineered virii?
Over 20,000 died, and up to 150,000 are still sick
If tits were wings it'd be flying around.
not the only swedish 17th century warship to have a catastrophic ending...
It took just one more little mishap to make a disaster: a titanium "wear strip" fell off a Continental DC-10 in the path of an Air France Concorde leaving Paris. When the Concorde's tire hit the strip, a chunk of rubber tore off and smashed into the wing, punching a 600-square-centimeter hole in its skin and causing fuel to leak and ignite.
Disclaimer: I know nothing about airplane safety or testing, but this one set off my common sense alarm.
So, the tires on Concordes require to be changed alot - a chunk of titanium breaks of of another plane, and hits a tire on a Concorde, causing the accident - anyone else think that "Well gee, I don't think any kind of tire is designed to withstand titanium chunks slamming into them." Considering the condition of some of the commercial jets I've flown in, I'll take my chances with the Concorde. I'm sure there is more to it than just this, I thought it odd though.
Though not a "disaster" per se - the Navy's dead Windows NT ship is tops for the funniest in my book.
There was supposed to be an Earth shattering kaboom!
If tits were wings it'd be flying around.
You can't breed out stupidity or rule out nasty ass-bad luck. This artical seems to infer you can do both.
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I live near KC and I remember when the skywalks collapsed. As the story unfolded after the tragedy, it became readily apparent that everyone just assumed everyone else was doing what they thought they should be doing or that their shortcuts were fine with everyone else. :-( Communication and checking up on how things are actually progressing versus the plans can be a real matter of life or death.
:sigh: Yeah, mistakes were made, so let's own up to them and learn something so we don't do it again.
Next time as a programmer you bitch about checking up on QA (assuming you are lucky to have a QA department) or on the users, just remember that your mistakes very rarely kill people. You've got it _easy_.
Also, on a side note, the local KC TV news organizations try hard to prevent people from getting to their archives of what happened. They don't want to present Kansas City in a "bad light". This is also very stupid. If we can't easily learn from our mistakes we are going to make more of them. 'Protecting' KC's reputation just makes Kansas Citians look more retarded than the screwup that was Hyatt Regency Skywalks.
"All the darkness in the world can not quench the light of one small candle."
10 Technology Disasters
By Eric Scigliano June 2002
What do a 17th-century Swedish warship, an opulent Chicago theater and a Kansas City hotel "skyway" have in common? All met catastrophic ends--and they have important lessons to teach today's innovators.
Let's face it: something draws us to a disaster, as long as it doesn't strike too close. And in all endeavors, but especially in technology, failures--even ghastly, gruesome, cataclysmic ones--can sometimes make better teachers than spectacular successes. The 10 examples offered below, drawn from a span of 373 years, show that though technologies change, many of the factors that make them go spectacularly wrong are surprisingly consistent: impatient clients who won't hear "no"; shady or lazy designers who cut corners; excess confidence in glamorous new technologies; and, of course, good old-fashioned hubris.
In assembling this list of exemplary technological disasters, we've omitted the most familiar--those whose names have entered into the language, like Bhopal, Chernobyl, Three Mile Island, Titanic and Challenger--in favor of some with fresher tales to tell and lessons to impart. These events vary widely as to when, where, how and why they happened. But they all show how trusted technologies can suddenly go wrong, and how flaws that seem trivial or, in retrospect, painfully obvious can have devastating consequences.
The Vasa sinking
The Swedish flagship Vasa's first and final sailing in August 1628 left fine fodder for future management consultants--an all-purpose cautionary tale of an overbearing but technically clueless boss pushing through his pet project. King Gustavus II Adolphus, striving to make Sweden a superpower, had wanted four new warships built fast. Workmen were already laying the Vasa's keel when the king ordered its length extended. His seasoned master shipwright, fearing to challenge the famously hot-tempered king, went ahead. The shipwright then took ill, directed the project as best he could from his sickbed and died before it was finished. His inexperienced assistant then took over, and the king ordered a second gun deck, possibly spurred by false reports that rival Denmark was building a ship with double gun decks. The result was the most lavishly appointed and heavily armed warship of its day, but one too long and too tall for its beam and ballast--a matchless array of features on an unstable platform. When the standard stability test of the day--30 sailors running from side to side trying to rock the boat--tilted the Vasa perilously, the test was canceled and the ship readied for launch. None of Gustavus's officials dared bear the bad news to the absent king, who was by then off warring in Poland and impatiently awaiting his new superweapon. Minutes after her grand launching, with all Stockholm watching, the Vasa heeled, listed and sank, killing about 50.
The Hyatt Regency walkway collapse
When three "floating walkways" crashed to the floor of Kansas City, MO's swank new Hyatt Regency on July 17, 1981, speculation first fixed on the patrons who'd been dancing on them: perhaps their high-stepping had set off a harmonic wave that made the sky bridges buckle and crumble.
The truth proved more prosaic. The hotel's engineers had originally designed two of the three walkways to hang on common, vertical metal rods. But the metal fabricator took a fatal shortcut, substituting shorter rods hanging from one level to the next. The second-floor walkway thus hung from the fourth-floor, doubling the weight on its connectors. The fabricator claimed to have requested approval for this change; the engineers insisted they weren't asked, though they had signed off on final drawings that included it. The designers had also asked to be on site during construction, when they might have spotted the change, but were rebuffed by an owner determined to avoid additional expense. When enough patrons filled the walkways, the connections gave way. Thanks to miscommunication and corner-cutting, 114 perished in the deadliest structural failure in U.S. history.
The Iroquois Theater blaze
What the Titanic's sinking represented at sea, the burning of Chicago's Iroquois Theater marked on land: a supposedly indestructible, up-to-the-minute design--in this case, a theater advertised as "absolutely fireproof"--destroyed with an enormous loss of life. The Iroquois's owners acted with as much haste and hubris as their Titanic counterparts, installing no firefighting equipment, forgoing fire drills and opening before the sprinkler system was ready. Instead, like so many others, they relied on a single technological magic bullet: an asbestos curtain that would drop down and shield the audience in the (rather common) event of a backstage fire. On Dec. 30, 1903, as vaudeville star Eddie Foy regaled the overcapacity crowd in Mr. Bluebeard, an oil-painted backdrop brushed against a hot calcium-arc spotlight and ignited. The asbestos curtain started dropping on cue but caught on a stage light. Crew and cast opened the stage door to flee, admitting a powerful gust that sent fireballs shooting out over the unshielded audience. Fleeing patrons either found the doors barred or could not turn the newfangled latches on them. Six hundred two died, more than twice the toll of "the Great Chicago Fire" 32 years earlier.
The Eschede train derailment
Sometimes even the safest technology is vulnerable to the not-so-perfect world around it. In the 34 years since the inauguration of high-speed rail, no line anywhere in the world had suffered a fatal accident. All that changed on June 3, 1998, on the Inter City Express line near Eschede in northern Germany, when a small improvement in comfort derailed this carefully managed system. High-speed trains generally run on solid "monobloc" metal wheels, but to dampen noise and vibration the Inter City Express (like many lower-speed light-rail systems) wrapped these in metal "tires" cushioned with rubber inserts. Inspectors examined the tires daily, but even ultrasound failed to detect a minute crack in one tire. It broke, causing a partial derailment. But the train continued upright and likely would have reached a safe stop if it hadn't chanced to pass under an old-style roadway bridge that, unlike newer bridges, rested on a central pillar, which stood between the line's two tracks. A swinging car clipped the pillar, and the bridge collapsed on the train, causing a massive pileup and 101 deaths. So it goes, all too often, when new, high-performance technology is inserted into older infrastructure built to operate with a greater margin of error. The high-speed train was a round peg in the square hole of an outdated rail corridor.
The Ashtabula Creek Bridge wreck
The United States' deadliest bridge collapse demonstrates the dangers in transposing what works in one material to a new, unproven one. In 1863, Cleveland railroad magnate Amasa B. Stone Jr. announced a bold advance in bridge technology--so bold it was never imitated. For two decades, the state of the art in American bridge design had been the reliable Howe wooden truss system, which added threaded iron upright supports to a classic structure of diagonal wooden trusses. The iron connectors provided more strength and eliminated the painstaking joinery of all-wood truss construction. So, Stone reasoned, why not go all the way and re-create the Howe design entirely in iron? Trusting too much in this newer, costlier material, Stone ignored both its potential for hidden weak spots and an essential flaw in his design: the bridge was assembled like an interlocking jigsaw, held together by pressure rather than the firm attachments of the wood originals; if one joint went, the whole structure would. Nevertheless, Stone proclaimed his 1865 creation "absolutely sound," and it stood for 11 years, even as its parts shifted. Then, on Dec. 29, 1876, as a passenger train crossed, an iron support with a hidden air bubble collapsed, the bridge tumbled down, fires spread from the train's tipped-over woodstoves, and more than 100 riders perished.
The St. Francis Dam burst
It's never wise to underestimate the forces of nature. William Mulholland, creator of the Los Angeles water system and a designer of the Hoover Dam and Panama Canal, met his Waterloo at the little-remembered St. Francis Dam in San Francisquito Canyon, 72 kilometers northwest of L.A. On March 12, 1928, one day after Mulholland examined it and declared it sound, the dam burst, sending a wall of water, reported as 24 meters high, hurtling toward the Pacific. More than 500 people in its path perished. An inquest blamed unstable rock formations for the collapse, but later investigation suggests that the dam's base was thinner than believed, and its engineers did not fully understand uplift forces or build in seepage relief. The underlying failure was more universal: the United States saw a boom in dam building in the first decades of the 20th century, as engineers threw up walls against the waters in unfamiliar terrain and on a scale never before attempted. They did so in large part by guesswork and extrapolation from much smaller projects. Ambition outpaced knowledge, and inevitably some of the new dams failed--most catastrophically the St. Francis. But its collapse left an important legacy: the world's first dam safety agency, uniform engineering testing criteria and a state-mandated process for arbitrating wrongful-death suits still used today. Too late for Mulholland: "I envy the dead," he intoned at the inquest, and faded into seclusion.
The Atlantic Empress/Aegean Captain collision
If ever there was an accident waiting to happen, it was your typical oil supertanker. These floating monsters can stretch over 400 meters, weigh more than 400,000 metric tons and require five kilometers to stop. And yet they are astonishingly undermanned, underpowered and ill prepared for unexpected problems. Where many smaller ships use multiple propellers to steer and brake, most tankers have just a single massive propeller. And the tools that help compensate for these limitations can contribute to a false sense of security; two ships relying on radar, which is great for navigating unchanging environments, may wind up traveling too fast to break from a collision course. Industry critics warned of an eventual collision between two supertankers, and on July 19, 1979, it happened: the Atlantic Empress and the Aegean Captain (which was apparently hauling bootleg oil to apartheid South Africa) collided near Tobago in an unexceptional rainstorm. Together they lost 26 crewmembers and spilled more than 185 million liters of oil--more than four and a half times as much as the Exxon Valdez spilled in 1989. But because it happened out of sight, this, the largest tanker spill ever, was soon out of mind and off the news.
The day AT&T's lines went dead
The Y2K bug was the long-awaited disaster that didn't happen; the AT&T crash 10 years earlier was the software disaster everyone thought couldn't happen. Ma Bell had one of the world's largest and most famously reliable networks: hurricanes and earthquakes couldn't shake it, a 1989 U.S. Congressional report on the general unreliability of government software lauded the dependability of AT&T's, and the company's ads impugned the glitches that pestered upstart competitors Sprint and MCI. Then, on Jan. 15, 1990, a single switch at one of AT&T's 114 switching centers suffered a minor mechanical malfunction, momentarily shutting down that center. When it came back up, it sent out a signal that made other centers trip and reset--and send out similar signals. The centers crashed, writes Leonard Lee in The Day the Phones Stopped, "like a hundred mud wrestlers crowded into a too-small arena," each pulling himself up by pulling down the others. American Airlines estimated it lost 200,000 reservation calls, and CBS couldn't even reach its local bureaus to check on the story. The culprit proved to be a single line of faulty code in a complex software upgrade recently implemented to speed up calling. AT&T's much touted backup switching system carried the same fault and suffered the same crash. "The condition spread," AT&T chairman Robert Allen confessed afterward, "because of our own redundancy." The company did not keep that redundancy sufficiently insulated from the main system; it could have retained the old software in its backup system until it had thoroughly road-tested the new. But just maybe, the company's programmers had come to believe their own good press.
The 1965 Northeast blackout
California's rolling blackouts in 2001 sent pundits harking back to the great 1965 Northeast blackout. But reckless deregulation, market manipulation and artificial shortages did not figure there as in California. Instead, the causes were technical--and stemmed from efforts to prevent shortages and blackouts. When electricity usage soared in the 1950s, power companies sought to ensure supplies by joining New York, New England and Ontario in a vast grid. When demand spiked in one locale, others would fill it. But in a twist that illustrates just how difficult it can be to predict how vast, complex networks will actually work, the engineers didn't anticipate the effects surging supply in one area might have on others--effects that brought the whole grid down. The trigger was a single relay switch on a line bearing power from Niagara to Ontario, which had been set to trip off if power surged past a certain level. On Nov. 9, 1965, the power load exceeded that level, the switch tripped off--and the power that would have flowed to Toronto surged back into western New York, swamping the lines and causing generators to shut off to avoid getting fried. The cycle spread, south to New York City and east to the Maine border. Thirty million people across 207,200 square kilometers were cast into darkness. New Yorkers, who afterward claimed the regionwide blackout as their own, muddled through peaceably--dining out by candlelight, sleeping by the thousands in hotel lobbies, helping strangers. But one famed outcome--a baby boom nine months later--proved to be just legend.
The Concorde crash
Until July 25, 2000, the supersonic Concorde was aviation's star in safety as well as speed. Before its first flight, its engineers tested it longer--for 5,000 hours--than any other plane in history; in 26 years and tens of millions of kilometers of transatlantic flights, the Concorde fleet had suffered not a single fatality. But for all its superb structural, aerodynamic and propulsion design, the Concorde bore a fatal combination of lower-tech flaws--proving the adage that it's the little things that'll get you. Its high takeoff speeds wore hard on its tires, which would often blow out despite being changed five times as often as those on an ordinary jet. And the fuel tanks in its wings were not strongly reinforced against impact, a precaution standard in newer planes.
It took just one more little mishap to make a disaster: a titanium "wear strip" fell off a Continental DC-10 in the path of an Air France Concorde leaving Paris. When the Concorde's tire hit the strip, a chunk of rubber tore off and smashed into the wing, punching a 600-square-centimeter hole in its skin and causing fuel to leak and ignite. The resulting crash killed all 109 people aboard the flight, as well as four on the ground. Air France and British Airways subsequently installed new tires tested to repel titanium strips at speeds up to 403 kilometers an hour, as well as undercarriage reinforcements and bulletproof tank liners to prevent similar fuel leaks. One arguably foreseeable accident source had, belatedly, been eliminated.
Seriously: ten catastrophic goofs, but I don't see anything which really ties them together!
Am I missing something?
Yeah, sure "Don't cut corners" and "Don't trust management who would like to cut corners", but that's pretty obvious and we all still do it, right?
There's also some stuff like "Watch when retrofitting parts of an old system with new technology" and "pay attention to boundry conditions", but really I think this is just a laundry list.
So does anybody know of a good reference work out there which actually has some worthwhile analysis on stuff like this? Didn't Feynmann write something up after Challenger?
Hexayurt - open source refugee shelter,
A story that claims to be reporting on the greatest tech disasters, in particular the lesser known ones, and it fails to mention Banqiao and Shimantan in 1975?
I mean, not only was this the greatest technological disaster in human history with 80,000 to 230,000 dead depending on whose numbers you believe, but it also is sufficiently unknown that the author of an article on disasters doesn't appear to know of it!
Has it been over a year since you last donated to the Electronic Frontier Foundation
No, let's get this right. Humans inherently lead to disaster, just like Communism would actually work if people weren't ivolved. Technology, like so many other things, is simply a tool.
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From the note
Things to come. The chemicals that poured from Carbide's plant killed thousands of citizens of Bhopal, wrecked the health of a generation unborn and poisoned the land around the plant, which to this day remains steeped in dangerous poisons. Union Carbide has declared that its connection with Bhopal is finished. If only it were true. Meanwhile the company is presenting itself as a born-again environmental leader.
This sorry is gay, and so are you.
It deserves +10 at least!
Another disaster can be viewed here [disasterrecovery.org]
-
Comment removed based on user account deletion
Microsoft Windows :-)
No discussion of the topic could be complete without mentioning RISKS. The RISKS Digest has been discussing risk factors associated with technology and engineering (and to some extent generally) on the internet since 1986.
Every engineer should spend time reading there. Any _good_ engineer should subscribe.
-David
We're on the road to Tycho.
but does it have that bridge on the list. its not a technology disaster list unless its got that bridge that harmonically shook itself to death. footage of the old guy walking across the bucking bridge is just cool as hell.
-
Same principle (harmonics), somewhat larger scale.
A nice movie can be found here.
See http://www.brisray.co.uk/misc/mind.htm (scroll down) for more info.
This is what happens when you have a system that allows the corporation to run amuck.
The lowest bidder cannot be trusted to create products that are safe.
In these cases, it is good to still have some government oversight.
"Can of worms? The can is open... the worms are everywhere."
Yes, it appeared as an appendix to the Roger's Report. He also discussed it in his autobigraphy either "Surely your joking..." or "What do you care...", I can't remember which. The appendix is a good read, and can be found here:
http://www.ralentz.com/old/space/feynman-r
or any of a number of other googleable links.
I'm a consultant - I convert gibberish into cash-flow.
Sadly, the most obvious and recent one was not on the list: my basement.
I'm the Devil the Windows users warned you about.
Dos
Windows 1.x
Windows 2.x
Windows 3.x
Windows 9.x
Windows Me
Windows nt
Windows 2000
Windows XP
And the worst technology desaster...
Microsoft Bob
The difference between Canada and the USA is that in Canada healthcare is a right and gun ownership is a privilege.
Even if you never get near embedded systems of this type, you can't call yourself a responsible software engineer until you read and learn from An Investigation of the Therac-25 Accidents.
Executive Summary: Company introduces next-generation radiation therapy machine, replacing hardware-based overdosage safety interlocks with software-based mechanisms. Software fails. People are killed.
Schwab
Editor, A1-AAA AmeriCaptions
Read the article... or watch Discovery. It was a poorly designed set of walk ways unable to take the load, not harmonics.
"There's also some stuff like "Watch when retrofitting parts of an old system with new technology"
Tennessee is just about to do something similar with a
nuclear power plant. This plant has been mothballed since 1985 but they want to bring it back online. Oh yeah, they also want to overclock it by 30%; it was originally designed for 1000 megawatts production but they are going to crank it up to 1300 megawatts.
The plant had caught fire in 1975, causing a series of problems leading to the shutdown in 1985. Now they want to extend it's orginal 40 year design for another 20 years. A nuclear-safety engineer for the Union of Concerned Scientists figures that a new plant would be safer and cheaper. From an engineering point of view, "It's like trying to dust off an eight-track tape player rather than buying a DVD system..."
First Three Mile Island. Then Chernobyl. Is Tennessee next?
Flamebait, Redundant, Troll. And DOS wasn't half bad.
From the article And a little bit later in the article
GO ARMY!!!!!!!
We had to destroy the sig to save the sig.
In 1917 collision between two ships in Halifax harbor -- one carrying close to 3000 tons of high explosive -- resulted in an explosion which levelled much of the city and killed 2000 people, in what was one of the largest non-nuclear manmade explosions in history.
Toronto-area transit rider? Rate your ride.
A disaster of epic proportions!!
I've been told AT&T's crash was due to a missing "break" in a "case" statement.
To this day, I don't know why C made passing the default and having to enter "break", rather than adding a "pass" keyword and making break be the default. And of course Java had to follow suit, resulting in a lineage of similar bugs....
Also: I have no idea why this works.
Design Paradigms Case histories of error in judgment in engineering Henry Pertoski, Cambridge press 94.
Wait... People can bash MS all day long without a Troll or an Off-topic mod, but this guy gets a -1? Yeah, I can see the light, and it's leaking out the ass of some reverse biased mofo.
That's why I took whatshisnames rule of thumb for my own- All off-topic and trolls will be meta-moderated unfair. Suck it up.
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This is why ‭
for Mr. Bill Gates
every engineer has their own stories of how they SNAFU-ed. I have mine (one of the reasons why I wuss-ed out and now do theoretical physics instead :)).
:
Usually, the problem is
(a) Pushing Envelope without prior analysis (Vasa)
(b) Not exercising Due Diligence in design (Tacoma Narrows)
(c) Failure of communication between departments (Mars Climate Orbiter : remember the units SNAFU?)
(d) Insufficent redundancy design (Iroquis Fire)
(e) Failure to recognize likely failure modes (Concorde, Titanic)
and others of course.
I've once fucked up an expensive spacecraft component because of (c). I worked on the mechanical design of the component housing, some electronics guy worked on the electronics detector sitting inside my housing. We have an innovative design whereby some of my mechanical supports were designed to keep some of his electronics ICs in place without the PCB board. The SNAFU : both of us thought the other is suppose to apply anti-vibration gell (layman's term here, we call it RTD...).
So the part was fab-ed, electronics put in, and the whole thing was sent to a vibration table for testing..
Result : a loose IC, clanking around the housing for 2 minutes at about 600Hz. The whole thing was toast.
Mode (3) smart-aleck mode. Press * to return to main menu.
I can't believe they didn't put the Tacoma Narrows Bridge on there!
General Relativity: Space-time tells matter where to go; Matter tells space-time what shape to be.
In August 1996, the Western Intertie - a particular grid of tied wires that supplies the western states with power - apparently overheated, promptly shutting down large parts of eight states.
More information - although with an environmental bias - can be found at this site here.
This sig no verb.
Imagine if DigiScents hadn't ran out of money.
At least the air freshener industry would benefit for the next 20 years as we attempt to de-stink the world
-- If you try to fail and succeed, which have you done? - Uli's moose
How is this for a real disaster?
d is aster.html
... I don't smoke, but I do ride a motorcycle,climb, dive, etc. So, yeah I am a bit of a hypocrite.)
http://www.tobaccofreedom.org/issues/disasters/
(watch for the space
(Before y'all jump on me
"Consistency is contrary to nature, contrary to life. The only completely consistent people are the dead." A. Huxley
In case anyone is interested this story is in the current issue of the dead-tree edition of the magazine. Really interesting stuff!
1300 megawatts? That's more than enough to send it back in time. If only we could get it up to 88mph...
OK, maybe the number of deaths wasn't a record, but the Space Shuttle Challanger disaster should rank up there as a technological disaster (anyone remember Feynman's presentation about the O-rings?)
Um, Ahoy there, but it's not his job to write good code just like it's not your job to build a car. Call it a hunch, but I'm betting you have an opinion about cars anyway, even though you probably have no inkling how to build one that works.
(in case you actually can build a car that works, insert an area of expertise you know jack about and the same will still apply)
Fancy pants.
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Lol see topic please!
Heck, the ancient Chinese used to strap people into giant kites as airborne scouts. Of course, landing was a bit of a pickle.
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Notes that moderations are being changed across the board to flamebait/troll no matter who they support. That's a start, I guess.
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I was at work, and when I walked by a radio I caught something about Concorde. I yelled to my boss "The Concorde crashed I think!". He said. "No way, it can't crash, it's the Concorde."
For me, an aerospace buff, that crash was as big as the Challenger.
I remeber when the transcripts from the Concorde crash were released, it was really chilling, thinking about those pilots, knowing something bad is happening, and trying with all thier might to abort to Le Bourget, and that big Delta is stalling and Christian Marty can only say "Too late".
Heat Troller Trouble Shooting Guide
.8
Most problems are the cause of two things.
1. Reverse Polarity. This can happen to the smartest guys and the biggest shops. I even did it. It is a very easy problem to diagnose since the LED will not go on and the heat will stay full on even with the switch turned off.
You can do a visual check. simply go to the plus post of the battery and take the wire from the battery harness in your hand. Run your hand up the wire and see that the fuse holder is attached to that wire. If not then you have the harness on backwards. If you have the fuse holder there, then continue up to the plug on the end of the harness and make sure that the side of the plug that is covered is attached to the wire you have been following. Some times these connectors can be put on wrong.
If you are using a BMW plug and you did not get it from us then you should test it to see if that has been wired correctly. The ones we make are filled with hot glue so there is no way to look inside to see how it is wired. You need a meter that will tell you continuity. the easiest ones to use will make a noise when there is continuity. Simply put one probe on the center tipof the BMW plug and one probe on the covered side of the SAE connector at the end of the cable. It should be where you plug the Heat-troller into the adapter. It should show continuity, these two points are attached. You should also test to make sure that if you have an after market BMW socket installed that it also has the polarity correct. Set your meter on Volts DC and using the red probe in the center of the socket, touch the ground probe to the interior side of the socket. it should show a 12 to 14 volts. if it shows a minus number then the socket is not wired up correctly.
2. Short in the Clothing. A short in the clothing can be caused by a number of things and it is usually seen in the gloves or socks where the connector wire and the resistance wire get a lot of stress. The sign in the past was for the Heat-troller to get very hot and show signs of melting. The fuse on the battery harness would sometimes blow. We now install a thermal fuse in the Heat-troller that will kill the unit if it encounters this problem or anything similar. The sign of this problem is that right before the Heat-troller dies, the clothing will go to full heat. Often people assume that the problem is in the Heat-troller and will get a replacement and at some point, it will happen again. Because the short is floating and depends on just when the wires touch, it can be months between episodes. In one case a customer had a short in one of four socks. He would kill the Heat-troller when he just happened to pick that one sock to wear.
Testing for a shorted thermal fuse is easy if you have a meter. Set for continuity test, put one probe in the covered side of the white banded Power Out connector and one in the uncovered side of the red banded Power In connector. If the internal sue is good then you will have continuity. If you do not then the fuse has died and you should do a quick check of the clothing. Although, i have to warn you that unless you get the wires just right, they may not show the short. Set the meter to check for resistance. Put one probe in one side of the connector to the clothing and the other probe in the other side. Below is a list of what it should show, more or less. If you get a zero then you have a short.
Gloves: 9.8 each
Pants: 2.6
Jacket: 1.6
Socks: 9.7 each
Full suit (with socks):
Weird Problem 1. The Heat-troller is plugged into the battery harness correctly, the battery harness is connected to the battery correctly and the heated product gets warm but it cannot be controlled by the Heat-troller. Plus the heated clothing gets warm even with the controller turned off. The LED is lit all the time. The customer ran some tests himself and complained that the heat-troller unit was defective.
1. Some problems are easy to solve, others take time. Some we never solve. After going round and round with this one we were convinced that we had a problem that we had no solution for until the customer solved it himself. In all the times we talked to him he forgot to tell us one crucial piece of information. He wanted to test the drop of power between the battery and the heated liner he owns. He plugged a probe into the plus side of the glove connector at the end of the sleeve, and then plugged the other probe, the common side of the meter, to the battery. Exactly correct for making this type of test. However, he didn't tell us how he ran the test. If we had we would explain why the controller was coming on with this type of test. Remember, there is no way you can or would do this in real use of the products. He told me that the solution came to him as he lay in bed. Being that we are using DC power not AC, our Heat-troller, like all normal DC devices, switch power to the ground side. That means that if you stick a probe to the plus side of output and the other side to the battery, you have just completed the circuit. Or turned the Heat-troller on.
We had three customers with the same "problem" in one week. In each case none of them mentioned that they were using a test probe but because one customer was good enough to stay in touch and not feel embarrassed by his confusion, we were able to solve this problem for other customers. We had already built him a new unit to see if there was a problem in his but he declined and said there was nothing wrong with his. We still get people doing variations of this. The latest was due to grounding a BMW socket to the frame.
Weird Problem 2. When the Heat-troller is turned on, I find that my headlights strobe to the pulsing of the LED.
1. The cause and solution of the problem is simple. The cause is that you are trying to draw more power from your charging system than is available. There is two solutions. You can cut back demand to equal the ability for your charging system to keep up. Or you can request a new unit and trade in your old one plus $20. With the new unit the strobing will stop. You will get dimming of your headlights since you a still trying to draw more power than is being produced. Also the LED will not flash but will go from dim to bright.
Weird Problem 3. The Heat-troller stays on full even when turned off and the LED stays on dim or may flash when the Heat-troller is turned off.On the new Mounted Heat-troller, the board that holds the switch can get covered with road grime and soap to the point where, if it gets wet, there is enough resistance between the solder points of the wire going to the Heat-troller box that a connection is made. Solution is to take Radio Shack Color Tuner Cleaner or alcohol and a toothbrush and clean the solder side of the board really well. Then cover the solder points with either dielectric grease or nail polish.
Weird Problem 4. The knob turns too easily.
Is the rotation of the switch too light for your needs? Is it being bumped and turning too easily? We have a clean solution. Get an O-ring at your local hardware or plumbing store. Ask for a 2-201 size. Then remove the knob on your Heat-troller(TM). Push the O-ring on to the shaft. Replace the knob. The knob has a small indentation that the O-ring will sit in. As the shaft and knob turn, resistance comes from rubbing along the O-ring. How deep you place the knob on the shaft will can change the resistance, and change the ease in which the knob turns.
Weird Problem 5. The LED glows even though the switch is off and then clothes are unplugged.
This Problem showed up on the new Heat-troller 6. If the exposed pin of the white connector (the one that plugs into the jacket) makes even a poor connection to the bike frame, the LED will glow. The better the connection, the brighter the glow, but that doesn't indicate a problem with the controller. It will not cause much of a drain on the battery and will not damage the bike. Even water could act as a bridge between the connector and the frame.
Krama: Bigdickinyoura
Hey groovy... saving this one...
It was in "What do you care..."
General Relativity: Space-time tells matter where to go; Matter tells space-time what shape to be.
Rather, a break in the wrong place - trying to break out of the enclosing if(){}, but actually breaking out of the enclosing switch.
;-)
A clear case where a goto would have been more appropriate
himi
My very own DeCSS mirror.
Don't you mean THE largest non-nuclear manmade explosion? I didn't think there were any bigger booms.
the Navy's dead Windows NT ship is tops for the funniest in my book.
Many psychologists have suggested that the emotion of humor has evolved as expressing relief from danger.
I find it truly frightening.
- passion
As a Slashdot submission would be the .... "Thirteenth Ghost"
8')
Dw
How much is your data worth? Back it up now.
I live in KC, and remember thinking that the guys who designed the skywalks got a bum rap.
They were designed for people to walk from one side to the other, perhaps to pause and
check out the view for a few moments before continuing on their way, but not for a huge
crowd to fill them, swaying in unison in rhythm to the music. I have a great deal of sympathy
for the people on the lower skywalk and those underneath them both, but the ones on the
upper skywalk contributed to their own injuries. I never saw any acknowledgment of this
distinction.
[100% ISO 646 Compliant]
SVM, ERGO MONSTRO.
There are some pictures on this page. It seems that over 600 people died; or at least they recovered that many bodies. There may have been some who simply disappeared. There was a tidal wave which swept 150 feet inland (NOT 150 feet high, but that far away from the beach.). Since the ship was at the dock, it started fires in the town, and at a chemical plant near the docks. It set fire to another ship which was nearby. That ship blew up the next morning with even more force, and did even more damage. There are more pictures here and here, which give some idea of just how big ithe explosions were.
See what I've been reading.
It was "Waht do you care what other people think". Excellent book - i also have a copy that he voiced. Everyone should be exposed to Feynman - it's so rare to find people so capable who communicate so well. Feynman lives! (should see ghengis blues too ;p )
"Sanity is not statistical", George Orwell, "1984"
Even better is Roger Boisjoly's lectures on Challenger. He was the engineer who, the night before launch, told management that it was too cold and that the O-Ring would break.
You can read his lectures online
Become a FSF associate member before the low #s are used
http://www.sciam.com/1998/1198issue/1198techbus2.h tml
"Others insist that NT was not the culprit. According to Lieutenant Commander Roderick Fraser, who was the chief engineer on board the ship at the time of the incident, the fault was with certain applications that were developed by CAE Electronics in Leesburg, Va. As Harvey McKelvey, former director of navy programs for CAE, admits, "If you want to put a stick in anybody's eye, it should be in ours." But McKelvey adds that the crash would not have happened if the navy had been using a production version of the CAE software, which he asserts has safeguards to prevent the type of failure that occurred."
For a great analysis of why the Titanic sank, see Roy Brander's articles
-- "At Microsoft, quality is job 1.1" -- PC Magazine, Nov. 1994
Shhhh, the Illuminati doesn't want anyone to find out that all the disasters in history are linked by a common cause and were engineered by their Disaster Organization Committee.
This Space Intentionally Left Blank
Phrogger wrote:
m
... well there was no US version, except the real life one on September 11th, 2001. Tristar, why was "Rebirth of Mothra 3" never released so we could have been warned as Mothra clearly intended?
> First Three Mile Island. Then Chernobyl. Is Tennessee next?
Sorry, Tennessee would have to get in line. One of the most spectacular examples of stupidity causing a nuclear accident was at a plant in Tokai-mura on September 30th 1999, and it is the greatest nuclear plant accident in Japan's history. Basically, they dumped all the safety precautions and mixed themselves up a batch of acidic nuclear soup in a big steel bucket and stirred. Instant hot fission! You can read the World Nuclear Association's writeup here (it has a nifty table of different levels of nuclear catastrophe that is a must read):
http://www.world-nuclear.org/info/inf37print.ht
The interesting thing is, Toho was filming on location at the Tokai plants for a Godzilla attack in the then upcoming "Godzilla 2000 Millenium". They were probably done with filming by the time the accident actually occured. In December 1999, the movie opened, with Godzilla heading over to attack the plants.
This wasn't the first one of Toho's monster movies to "come true", only one in a long history. Here are two other famous ones:
"Gojira" 1984: the Russians have a nuclear accident in the movie (in the original Japanese version, US version makes it a deliberate act). In 1986, the Russians had a real accident: Chernobyl.
"Mosura 3: King Ghidora Raisu" 1998: the King of Terror (King Ghidora) begins his attack on Tokyo by flying through the twin towers of a skyscraper. Office workers flee while talking on cell phones. The US version
Sonora:"New Godzilla reading. He's moving inward toward Tokai."
Shinoda: "The nuclear plants, I knew it.
Sonora: "Afraid so."
Yuki: "Well, that's just lovely. Another Chernobyl."
"Godzilla 2000" (US version dialog)
DOS 6.2
Win 1.0
Win 3.1
Win 95
Win 98
Win CE
Win ME
Win NT
Win 2k
Win XP
[alk]
Maybe if they had added "until then".
In an ideal world they would build a new one.. but it would be impossible in todays climate. No new nuclear power plant has been built in the US since the 80's (I believe.. might be a little earlier/later). It causes too much of an uproar - NIMBY. Plus, you get wacky SUV driving soccer moms who complain about how much nuclear plants 'pollute.' Sigh.
Saw a rather interesting documentary on the Triangle Shirt Waist Factory fire in New York (I think) near the turn of the century.. Essentially, a sweat shop went up in flames, and the owners had padlocked all the emergency exits. Whoever didnt burn to death plunged to the ground below, diving out of windows.
A couple people have probably mentioned the Hindenburg. The Hindenburg didnt crash because of sabotage, because of any engineering errors, or even because it was filled with hydrogen. Neither one of those are valid reasons, especially the hydrogen thoery. The hydrogen gas inside the blimp was doped with a substance that smelled like garlic, so the engineers and crew could smell hydrogen leaks if they occured. None were reported. A blimp like the Hindenburg contained pure hydrogen. Pure hydrogen by itself is NOT flammable -- An adequate mix of hydrogen and oxygen inside the ship would have been needed in order for it to ignite, and that mixture wasnt present. Besides, the footage of the accident clearly shows that there was no explosion -- It was only the outer skin that caught fire. The outer skin of the Hindenburg was coated with a combination paint and sealant that was both highly flammable, AND electrically conductive -- The prevailing theory on why the Hindenburg crashed is that the blimp collected so much static electricity during its descent into New Jersey (in a brief window inbetween thunderstorms, even..) that the charge eventually arc'ed, and ignited the outer skin of the craft. The Hindenburg crashed to earth not because of fire, but because of hydrogen loss.....all because of a poorly chosen paintjob, oddly enough..
Cheers,
Bowie J. Poag
The night before swedes resurfaced the Vasa ship in 1961, some finnish technology university students dived secretly to the ship, inserting a foot-tall Paavo Nurmi statue on top of the pile. (Paavo Nurmi was a legendary finnish long-range runner in the early 20th century.) When the swedes found the statue, it caused sensation in swedish marine archeology, and later even bigger splash in swedish press when they found out to have been fooled by finnish student "hack." :)
I believe Halifax was the largest accidental non-nuclear explosion.
The largest non-nuclear explosion was near Macao on December 28, 1992. 12,460 tons of TNT were used to blow up a mountain. They were clearing land for an airport.
Check out To Engineer Is Human: The Role of Failure in Successful Design by Henry Petroski (Amazon). It's not a reference work per se; it's written for the layman, but it's very good.
- Andreas
Signatures are a waste of bandwith
The final accident report found the Dutch Pilot entirely to blame. Ten seconds with google will find plenty of links, but if you are too lazy (grin), here's a short summary.
... at least, that's what they ended up being for 114 merry partygoers!
The Illuminati don't CARE if people hear the truth, because they won't believe it. That's all part of those merry funsters' game. Like George Bush proclaiming a "New World Order". Like the eye-in-a-pyramid on the US $1 note. Like the occult layout of Washington DC. They act blatantly knowing that people don't want to hear the truth. That's why they're going to get what they want. They already have enough power to be unstoppable. They play both sides in every conflict. They want to enslave us all.
From the article:The result was the most lavishly appointed and heavily armed warship of its day, but one too long and too tall for its beam and ballast--a matchless array of features on an unstable platform.
That's like Windows, right?
12: Hitting submit accidentally while trying to write a witty response to a /.article
13: Jar Jar Binks
(14: realising that your post isn't really that witty, but will be viewable on the web for ever more)
Speaking of technology disasters- What about Microsoft Outlook, whose many unfixed security flaws have brought about waves of email-borne virii, costing millions of dollars in lost data and productivity?
a matchless array of features on an unstable platform.
Someone else make the joke, I'm feeling lazy
There are some people that if they don't know, you can't tell 'em.
Here is a link to the vasa museum
http://www.vasamuseet.se/indexeng.html
The most interesting thing about vasa is biological.
Due to the lack of shipworm in the baltic sea and the anaerobic environment where the ship sunk, the Vasa was very well preserved after 350 years in the sea.
As the bronze cannons were very valuable, most of them where salvaged during the years after the ship sunk.
Warning: This sig contains a small bug. ==> *
many of the factors that make them go spectacularly wrong are surprisingly consistent: impatient clients who won't hear "no"; shady or lazy designers who cut corners; excess confidence in glamorous new technologies; and, of course, good old-fashioned hubris.
This sounds like every software project I've ever worked on
Why doesn't Slashdot ever get slashdotted?
if it had been a BA concorde it might have been quite a different incident. There had been previous tyre blowouts which gave concern about the routing of fuel lines and hydraulics around the wheel bay area. BA had the lines in their planes rerouted to lessen the chance of them being damaged, air france ignored the warnings and did nothing. It still wouldnt have stopped the fire but it could have prevented the loss of control authority and might have been enough to let them land at le Bourget. The fact that michelin modified the tyre without recertifying didnt help (the modifications they made didnt legaly require recertification i believe), the newer version stayed in much larger pieces after disintegrating than the original, and hence did substantially more damage to the wing. (BA used dunlop tyres i belive, so this is another point where it may have been different if it had been a BA aircraft)
It's now a massive visitor attraction. However, that's not without its own unfortunate side effects: I heard a report a few week back on the BBC that the wood is now rotting again in places due to the humidy in the air from the visitors' breath, perspiration, damp outer clothes on rainy days, etc.
More information at the Vasa Museum .
The article attributes the AT&T grid failure to AT&T's own software, but wasn't this software actually written by DSC (now Alcatel), and therefore wasn't DSC responsible to do code review and test?
The part saying that AT&T shouldn't have installed the new software in the backup network may be true - but only if it hadn't been too long before the bug occurred. Some software bugs do not show up for years. How long should AT&T have waited before decided that the software was safe?
Most of the blame should go to DSC for insufficient code review and test for such a critical piece of software.
...there would be no customers!
Infuriate left and right
Nobody could quite come up with an explanation of how exactly this happened. The cap'n was snoozing below decks, and the only conscious officer was some affirmative action promotion whose college degree was an MRS.
Analogies are dangerous, but consider a tail light assembly. Other than something like a bumber clamp-on type of thingee, you have almost no chance of being able to reuse it from one model of car to another. Your manager is right in no time being spent on making the code reuseable. It is worthwhile making the code a bit more general than necessary, but the crux is in making the code match the edge conditions that exist in the customer's requirements. That makes little subtle distinctions that do NOT transfer well.
Most of the problems mentioned here are related to mechanical engineering. Chemical engineering actually has a equally, or even more impressive, track record of screw ups. My persoal favorite were the guys at BASF who used explosives to break up 4500 tons of caked Mischsalz (ammonium nitrate+ammonium sulfate) with explosives, blowing up the plan and the surrounding suburb, and killing 500 people in the process.
They just built it too light and flimsy.
and now makes for a good museum in Stockholm, where you can learn the history and see the warship Vasa.
I could be wrong, but I seem to recall from my physics paper that this explosion provided the inspiration for the Manhatten Project's Hundred-Ton test (of conventional explosives), designed to help figure out what a multi-kiloton explosion would be like.
I'm the stranger...posting to
You just have to ignore all the opinion that goes along with it and form your own conclusion.
I mean, did you know about the Solaris problems? I didn't, and I find it interesting. I mean sure, every UNIX deviates a little, and causes some compatibility problems, but I have really been bothered by the attitude displayed in some of the GNU documentation. For example, I remember reading about the gcc extensions, and how you should go ahead and use them because everybody should be using gcc.
RISKS is a big pile of random technology problems, accompanied by off-the-cuff commentary usually by non-experts (who don't seem to shout "I am not an expert!" as typically as most discussion groups). It makes a great jumping-off point for case studies for the continuous education any good tech needs, but a lousy source of pre-packaged judgements.
I mean, they let practically anyone post, you expect a zillion monkeys at keyboards to come up with a professional journal of technology risks?
Fire up Windows Calculator and dividing by zero yields:
A) 0
B) E
C) BSOD
D) 42
E) Domain Error
F) Error Positive Infinity
G) Undefined
H) None of the above
The correct answer (according to my test on Win98) was F, though I think G would be more accurate.
If the fine engineers at MS could avoid a BSOD in the calc application, it's fair to assume that division by zero is not a characteristic problem of Windows.
A GPF (or whaterver it is called) means Windows is doing it job as an O/S.
A BSOD means one of 2 things:
1) Windows failed to do its job
2) Windows is doing its job, protecting you from further damage due to a buggy device driver.
In practice, you as the consumer are pretty much hosed in any of the above cases.
Windows also fails to do it job in other ways, even on Win2K (usually considered the most stable), I've seen lost network connections, lost removable drive connections, Messed up screen font's, blank Icons, resource leaks (in the O/S),
Windows (including Solitaire) is the probably the greatest technological disaster of all time when measured in terms of dollars wasted.
Does Slashdot fall into this so-called "technology failures/disasters" category?
Why bother.
I had one manager who was adamant that for any medium sized project there ought to be NO time spent on making the code re-usable. Every line of code should be directly related to specific aspects of the customer's requirements/specification document. At first I thought he was crazy.
I had a guy who thought dynamic memory allocation should be avoided at all costs, and you should never use a data structure more complex than an array.
I still think he's crazy, but now I see his point. I mean, he was terrible for global variables and giant functions, but his programs never leaked memory and very rarely wrote to bad pointers. If you don't need dynamic memory allocation, you shouldn't use it, and when you do need it, you should only have one malloc and one free (or equivalent) for every dynamic data structure. Often, you only need one or two, even in a relatively large and featureful program. That way, I can write a good page of error handling code and comments on memory consumption for each dynamic memory access, and it saves me a lot of grief.
I don't like reusing code, either, unless you can make a good case for it being a part of the underlying system. I like the analogy of an architect stapling someone else's blueprint of a fully-equipped foundry and machine shop to his design because the inhabitants will need a screwdriver. Reuse means bloat, and bloat is bad. Every extra line you add is another place for a bug to hide.
I have no idea *what* it does. I seems to do nothing in Moz or Netscape 4.x
Anyone want to explain?
I'd recommend this book on failure analysis, written in layman's terms using case studies:
Why Buildings Fall Down: How Structures Fail; Matthys Levy, et al.; W.W. Norton ISBN: 039331152X; Reprint edition (1994); $14.95
There is also a companion book which I have not read (because I just found out about it when searching amazon.com):
Why Buildings Stand Up: The Strength of Architecture; W.W. Norton ISBN: 0393306763; Reissue edition (February 18, 2002); $14.95 ($10.47 at amazon)
Give me my freedom, and I'll take care of my own security, thank you.
How about that for a major engineering disaster? A rocket that was destroyed (actually, blew itself up deliberatly when its computer realised it was breaking up) because of an overflow error.
The engineering reason though, were that a component had been reused from Ariane 4 incorrectly, and the testing was inadequate - both of which seem to be common themes here.
Why do people keep making the same mistakes?
In 1940, the Tacoma Narrows Bridge collapsed" because insufficient stiffening allowed the wind to create oscillations that destroyed it.
... well, you get the picture.
...
Fast forward 61 years to London and the Millennium Bridge near-disaster where insufficient stiffening
Point is, a list such as this one is valuable ONLY if we remember and learn from it. Those who forget history are doomed
Engineering without complete understanding...gee, that sounds familiar. Genetic engineers these days proceed by trial and error. They splice a gene from one organism into another, expecting a particular change, which sometimes occurs, sometimes not; sometimes with drastic side effects, sometimes without side effects which anybody notices. The reason for this is that genes are not independent from each other - gene expression depends in part on the environment in the cell (ie the rest of the genome), and we don't yet understand all those interactions. This has not prevented us from introducing engineered organisms into the environment and food supply, without long-term tests of their effects on human health.
I have no philosophical objection to genetic engineering, but implementing it before we fully understand it seems to me even more dangerous than building dams without understanding civil engineering.
What about the expoding whale?
http://www.perp.com/whale/
ac
Isn't that a tautology ? ;-)
Anyway, nicely put, if not intended. Got to remember this.
This article mentions the "great AT&T problem" of 1989. But it doesn't mention the corporate witch-hunt for "hackers" which was known as Operation Sundevil. Everyone at AT&T was so hopped up on their own hubris, they assumed that the telecom problem that shut down exchanges in NYC and elsewhere had to be cause be (malicious) human hands.
The complete details are set out in Bruce Sterling's book "The Hacker Crackdown." Operation Sundevil also lead to the creation of the Electronic Frontier Foundation.
--
Internet Explorer (n): Another bug -- that is, a feature that can't be turned off -- in Windows.
Sure, nobody ever thought jetliners filled with aviation fuel would hit the towers. However, if anyone saw the recent NOVA "Why The Towers Fell" you would see that various shortcomings in the design of the building aided in the collapse.
http://www.pbs.org/wgbh/nova/wtc/
Engineer's report here:
http://www.pbs.org/wgbh/nova/wtc/collapse2.html
1) The walls made of sheet rock in the building's core completely shattered and exposed the metal beams when the planes hit, and thus the fires melted the core. if they were made of concrete, chances are the buildings might have been still standing.
2) use of spray on fire insulation on the metal beams. When the planes hit it shook the insulation off and exposed the bare beams, losing their fire protection.
3) Angle clips used in the floor trusses werent strong enough to hold the trusses up when the floors started to buckle due to the tremendous heat, causing the pancaking effect which caused the floors to collapse.
2)
I was visiting Stockholm with my wife, as some of her relatives live around there. We went to see the Wasa ships wreck into Wasa museum, and when the visit was about to end, one swede said to me the line on subject: "You Finns have nothing like this."
;-)
I agreed, as our ships have always had a tendency of floating, instead of sinking immediately after sailing out from port.
It is a nice museum to visit, I can warmly recommend that if you ever visit Stockholm.
PS. If you have the opportunity, please ask how's the statue of Finnish runner, Paavo Nurmi, nowdays. It was found from the Wasa..
I've never really liked case statements in C or any other language. It doesn't make the code any shorter and introduces bugs like this one.
;
;
;
;
;
So instead of doing
switch {
case 1:
break;
case 2:
;
break;
case 3:
break;
}
do this:
if (case 1) {
} else if (case 2) {
} else if (case 3) {
}
Pretty simple, huh? It even takes up fewer lines!!
Make it Simple and Stupid.
:P.
Everything'll be fine
Mode (3) smart-aleck mode. Press * to return to main menu.
A couple of comments:
First of all, it is a mistake to assume that the only form of reuse is by class hierarchies. Lots of reuse is accomplished by actual non-inheritable classes which do specific things. ("Library routines", for instance, or classes like 'string' which are used to hold and manipulate data) Reuse doesn't need to create huge class hierarchies.
Second, if you have a real reuse program in place, then reusable components should come already with test code to exercise them. This has a major impact on the reliability of the code that uses them, not to mention time to market.
Third, Some kinds of projects benefit tremendously from reuse. The typical case is where a company has to do several not-quite-identical-but-highly-similar projects. Designing each one of these from scratch is tremendously wasteful. Furthermore, the result is likely to be unreliable due to the fact that each bug has to be tested for multiple times, whereas in a project with heavy reuse, fixing an error in one reusable component fixes that error in all projects that use it.
On the other hand, not all components should be expected to be reusable, since not every component in a project is a likely candidate for reuse. Designing something to be reusable when it is not likely to ever be reused is often a waste of time. Also, trying to reuse something that was not designed to be reused is likely to cause more problems than it solves. Still, in situations where reuse is beneficial, it can often be hugely beneficial, and can effectively reduce the effort required to build a project in half, a third, etc. so it should not be overlooked even despite these drawbacks.
I saw a documentary recently which suggested that even though the towers were designed to withstand the impact of an aircraft, no one gave much thought to what would happen AFTER the impact, and what effect the impact might have on specific components (like the building's core, and the fire-retardant coating on the steel beams that connected the outer walls to the inner core). It has been theorized that had these points of failure been considered, many more people may have survived, and the buildings might still be standing today.
It's in either "Great Construction Disasters" or "Why Buildings Fall Down." (I forget which.) What is generally not pointed out in the hotel case is that the walkway as originally designed was strong enough but physically impossible to build. It would have required threading a nut on a rod larger than the hole in the nut. Change approval came not from the original architect but from the on-site construction engineers.
The Tacoma Narrows bridge failure was due to the (at the time) poorly understood phenomenon of vortex shedding.
That's exactly what I meant! Thanks...
Infuriate left and right
There's a realable -- i.e., directed at laymen -- book about engineering failures called "To Engineer is Human." It's a little chatty, but interesting nonetheless; it highlights a bunch of disasters and _why_ they happened.