Monday, April 23, 2018

Southwest Airlines Flight 1380: Cracks in Airline Safety?

Over the last twenty years or so, the news about airline safety in the U. S. has been mainly good.  Before last week, the last time a passenger died in a U. S. commercial airliner accident was 2009, and for some time before that it's been true that the most dangerous part of a plane trip is the drive to the airport.  But on Tuesday April 17, the explosive decompression that resulted from an engine fan blade on Southwest Airlines flight 1380 hitting a window sucked passenger Jennifer Riordan partway out of the plane, and she later died of her injuries.  Captain Tammi Jo Shults received praise for her calm and expert handling of the crisis, bringing the plane safely to ground in Philadelphia without any other fatalities.  

Good safety records don't just happen.  They are the product of unceasing vigilance on the part of thousands of pilots, mechanics, traffic controllers, inspectors, and other members of a complex system that has to be continually monitored and managed well to make flying safe.  One of the routine measures that helps maintain safety is regularly scheduled inspections of parts of the aircraft subject to fatigue.  Fatigue can happen to any part that comes under mechanical stress during takeoff, flight, or landing.  And some of the most highly stressed parts are in the engine, of course:  the turbine blades that endure extreme centrifugal forces and thermal stress, as well as the fan blades—the big visible ones in the front of the engine in modern turbofan units. 

A turbine blade that breaks off rockets through the housing like a bullet, usually destroying the engine and often damaging other parts of the aircraft.  This happened back in 1989 to a DC-10, and unfortunately the blade happened to hit the fuselage at a critical point that severed all the hydraulic control lines.  Forced to steer only by manipulating the throttles of the remaining engines, the pilots crash-landed at an airport in Sioux City, Iowa. One hundred and eleven passengers died in that crash and 185 survived.

More recently, in 2016 a fan blade on a Southwest 737 from the same type of engine that failed on flight 1380 came loose and knocked away the entire inlet part of the engine.  One of the flying parts ripped a hole in the fuselage and decompressed the cabin, but the pilots managed to make an emergency landing without serious injuries to anyone.  The missing blade was never recovered, but investigation of the root that remained on the hub showed that fatigue cracking had occurred. 

I wasn't able to determine if the NTSB or the FAA issued any directives for increased scrutiny of these blades after the 2016 incident.  But in light of the more serious consequences of last week's accident, government authorities have ordered inspections of more than 700 Boeing 737s that use the CFM56-7B engine.  That is only about 10% of all such engines in use, but there may be technical reasons why only some of the engines need to be inspected.

While Captain Shults deserves praise for her cool handling of the situation, it's typical of media attention to accidents like this that the pilots get their pictures splashed around for taking a bad situation and making it turn out better than it could have, while the people who spend their lives making sure pilots don't have to be heroes remain unheard-of and unsung.  The media thrive on drama and narrow escapes.  You will never see a news headline that reads, "Flight XYZ lands safely on time with no fatalities or injuries," because that is exactly what we expect to happen.  The people I mentioned above who spend their lives making sure that 99.999... % of the time, the normal thing happens never get any public attention, despite the fact that we owe the amazing reliability of air travel to their dedication and diligence.

In the January 2018 issue of the historical journal Technology and Culture, two historians point out that their own profession is guilty of a similar prejudice or blindness.  Historians of technology typically focus on inventions, discovery, innovation, and disruption, and the people responsible for these things.  But Andrew Russell and Lee Vinsel have issued a call for writing histories of the "maintainers":  the people who fix things when they're broken, do regular preventive maintenance so things don't break in the first place where lives can be endangered, and generally keep existing systems and institutions running smoothly. 

I don't know how far Russell and Vinsel will get in their attempt to encourage historians to look at maintenance, but they have perceived the academic version of a general trend that could lead us into a lot of trouble if we let it continue.  It's the neglect of the people who do routine, ordinary, and even dull activities that are nevertheless vital to the continuance of modern civilization.

This neglect shows up in all sorts of ways:  in the cultural attitudes that tell young people to become a doctor, lawyer, or other highly-paid professional, or else abandon all hope for a decent respectable career and marriage; in the absurdly skewed pay scales that are tending to turn the U. S. into a culture of a small elite reigning over poorly-paid "unwashed masses"; and in the fading of a small-d democratic attitude that recognizes the vital contributions of even the lowliest and lowest-paid workers in an organization or an economy as being just as important as the CEO, but in a different way. 

So while I congratulate Captain Shults for her heroic actions to land Flight 1380, I hope that the nameless technicians, inspectors, bureaucrats, and others whose achievement it has been to make air transport as safe as it is will redouble their efforts to keep anything like the fan-blade accident from happening again.  And if they do their jobs well, maybe I won't have a chance to write about another commercial U. S. airline fatality until I'm too old to care.

Sources:  I referred to a BBC report on the Flight 1380 accident carried on the news organization's website on Apr. 21, 2018 at  I also referred to a report of the 2016 fan-blade accident at the NTSB website, a New Scientist article that appeared on Nov. 5, 2010 at, and the Wikipedia article "United Airlines Flight 232" about the 1989 turbine-blade accident.  The article "After Innovation, Turn to Maintenance" by Andrew L. Russell and Lee Vinsel appeared in the January 2018 issue of Technology and Culture, pp. 1-25.

Monday, April 16, 2018

Engineers and Corporate Leaks

A recent Bloomberg News item describes how Apple is going to great lengths to keep its engineers from leaking secrets to the media.  Historically, Apple has kept the public in the dark about its plans unless and until the company wants to reveal them, usually at a trade show where CEO Tim Cook or another leader gets to present the new product or feature amid ballyhoo and drama.  Leaks spoil the surprise, and so it's understandable that the corporation wants to suppress them.  But it hasn't been able to do that completely, and a recently published memo (also leaked, presumably) gives us some insight into the thinking that goes on at one of the world's largest tech companies about secrecy and leaks.

The memo, which was posted on the company's internal blog, says that in March a leaker who told outsiders about plans for Apple's software roadmap was caught and fired.  He didn't think he'd be caught, but the memo claims that in 2017, Apple caught 29 leakers who were either Apple employees, contractors, or suppliers, and 12 were arrested.  The memo points out that while a person may not start out intending to be a leaker, media people befriending you on Facebook probably have only one thing in mind—to find out what secrets you know.  If you're caught, you will not only lose your job at Apple and possibly face arrest, but you'll find it hard to get work in the industry anywhere else. 

The overall tone of the memo reminds me of those World War II propaganda posters that showed Hitler and Mussolini with huge ears leaning next to a sauced-looking GI at a bar who is obviously spilling military secrets to a good-looking gal who's writing them down under the table on a notebook strapped to her leg.  Maybe I'm combining a couple of posters there, but the point is that large organizations with secrets to keep have to convince their workers that it's a serious moral failing to tell confidential information to outsiders. 

The negative consequence of talking to spies in wartime is pretty obvious:  the enemy is out there to kill you and your fellow soldiers, and so why would you do anything that would make the enemy's job easier?  In the case of corporate secrets, the worst negative consequences of blabbing are not so clear.  I'm not aware that anyone outside of Apple has succeeded in marketing a look-alike knockoff iPad or iPhone, because such an achievement would require more than just a few random leaks to do. 

But the real issue is control:  control of information that Apple wants to release only when it suits its plans to do so.  As the article points out, the huge public investment in Apple stock creates a powerful incentive for reporters to find out what the company is up to in advance of Apple's planned announcements, because anything that affects the firm's stock price is of interest to its investors.  Hence the steady flow of leaks about product releases, features, and the timing of new products, despite Apple's stern memos about the despicability of leaking on the part of its engineers.

If Apple is like most tech corporations, every engineer (and maybe every employee down to the janitors who clean the floors at 1 Infinite Loop, for all I know) is made to sign a hiring agreement which, among other things, binds them to keep secret information secret.  So at a minimum, if an engineer leaks information to a reporter, the engineer is violating that agreement. 

There are situations in which such an action can be justified, but they are rare.  It's called whistleblowing.  If an engineer knows of a really bad situation that threatens public safety, for example, and supervisors refuse to do anything about it, sometimes the engineer is justified in going outside the company altogether to a reporter or government official in order to remedy the situation.  But none of the leaks that Apple is ticked off about seem to fit in that category. 

Software-intensive businesses like Apple can't rely only on patents to keep themselves ahead of the competition.  That is why trade secrecy plays such an important role in highly competitive businesses like consumer technology, and why Apple gets so upset when one of its engineers leaks confidential information.  Especially in the phone market, Apple is not the only player in town, and its concerns that important innovations it has expended a lot of effort on will be stolen by Samsung or another firm are real ones.

This is another example of a general rule about professional ethics:  with specialized knowledge comes specialized responsibilities.  Engineers whose work involves secret information that would harm the company's interests if conveyed to outsiders have an obligation to keep that information confidential.  Leakers have all sorts of motivations, ranging from the temptation to yield to the flattery of a reporter, to a desire for revenge for alleged mistreatment at work.  But working for a company, as the memo points out, is a relationship of trust.  And trust violated is no longer trust.

I'm not saying that Apple's secrecy policies are always justified.  In previous blogs, I have discussed some things that Apple does that do not appear to be in the best interest of its consumers.  And depending on the circumstances, it might be serving a higher morality for an engineer to let the public know that Apple is dealing unfairly with them. 

But whatever the reason for a leak, any engineer who deliberately leaks information should be prepared for the consequences.  Even whistleblowers whose actions appear to be completely justified in retrospect usually end up getting fired and becoming a pariah, not only in the company they blow the whistle on, but often in their entire industry.  It's not fair when that happens, but it happens. 

Secrecy is a strain on those who keep secrets, and now and then secrecy is used to cover up wrongdoing.  But most of the time, tech companies have good reasons for their secrets, and any engineer who presumes to ignore those reasons and talk to outsiders is taking a career-threatening risk.

Sources:  The article "Apple warns employees to stop leaking information, talks of arrests" by Mark Gurman of the Bloomberg News service appeared on Apr. 13, 2018 on the San Jose Mercury-News website at 

Monday, April 09, 2018

Facebook's Role in a Democracy

Over the last several weeks, the social media giant Facebook has been on the hotseat for its dealings with a consulting firm called Cambridge Analytics.  Evidently, Facebook shared the data of more than 80 million of its users with the firm, which was working for the Trump election campaign at the time.  The details are rather murky and one's view of this particular breach depends on one's political affiliation.  So rather than get down into the mudpit to sling more mud about this specific incident, I would rather take this opportunity to examine a more basic and far-reaching question.  What is the proper role of a huge social media company such as Facebook in a democracy?

To answer that question, we need to have some notion of how a well-functioning democracy works.  Political scientists generally regard a democracy as consisting of a government run by elected representatives.  The people (or some chosen subset thereof) get to vote for these representatives, and in turn the representatives construct and operate a government which observes certain rights of the people and subjects them to the rule of law. 

Speaking from an engineering point of view, a democracy can be considered to be a kind of control system.   Things needing the government's attention affect the votes and opinions of the masses, who elect representatives to do something about these things.  The representatives enact laws that ideally decrease the gap between the way things are and the way things ought to be.  That gap is never wholly closed this side of Paradise, but the narrower it gets, the better the democracy works.

Notice that in the description I just gave, the phrase "the way things ought to be" is really a statement of morality or justice.  In a country of over 300 million people, you are never going to get perfect agreement on anything, let alone matters of morality and justice.  But the beauty of democracy is that if most of the people broadly agree on something that the government can or should do, the democratic system has a way to deliver it.  And sometimes it even does.

Control systems have feedback loops, and in the most general view of such things, what is fed back is information.  And the same is true, broadly speaking, of democracies.  The people inform their representatives of their opinions about various matters by voting, as well as contacting them directly.  The representatives vote and pass bills using this information, and the information solidifies into laws, which are sort of like operating instructions for both the government and the people.  Anything that short-circuits or distorts this process is a potential threat to the proper functioning of a democracy.  In particular, any influence that can sway voters unduly or by fraudulent means must be carefully observed, and if necessary, dealt with somehow to restrain it from distorting the flow of information.

Newspapers have been around longer than the U. S. Constitution, and in the very early days of the country, some steps were taken to repress the freedom of the press.  But wiser heads quickly realized that to let the government say what could and could not be published was a gross distortion of the democratic process.  And so the First Amendment was passed to guarantee freedom of speech.  In doing so, the founders regarded the people as being wise enough to judge what opinions and alleged facts they should pay attention to in casting their ballots.  But the proper functioning of the system relies on that judgment, and ever since then there has been a tension between two extreme positions that the media can take in political activities.

One extreme is to attempt complete objectivity:  to report everything of significance in as unbiased a way as possible, and to let the voters make up their own minds.  This extreme was never approached very well, but in the glory days of the major city newspapers of the early and mid-twentieth century, the Associated Press came close, motivated as it was by its desire to sell its stories to newspapers of as wide a range of political persuasions as possible.  And when mass media required huge investments and consequently had only a few outlets (such as the three major TV networks that prevailed for the first thirty years or so of network TV), viewers usually got basically the same news from everywhere.  Maybe it was slanted somewhat, but at least everyone was working from the same page. 

But Facebook is as different from that as you can get, and comes closer in some individual instances to the other media extreme of total partisanship at the expense of reason and even truth.  Add to that the fact that huge parts of Facebook are a mystery to everyone outside it.  The old brick wall between the editorial and the advertisement sides of print journalism has vaporized, and the opinion writers are the readers are the advertisers.  Instead of a clean, easy-to-analyze feedback loop from the media to the voters to the government, we now have a messy tangle of voters who are the media, and who are also maybe Russians with secret axes to grind, and political operatives using data from millions to target certain groups without letting them know what is going on.  And it is all being done for profit, which isn't necessarily a bad thing.  But unlike the old simple lines of profit from print advertisers, whose ads could usually be clearly distinguished from editorial matter, the motives of Facebook and its paying customers are confused, obscure, and sometimes even contradictory.

Can a democracy function when such a confusing mess plays a significant role in elections?  Our democracy is still functioning, in the sense that we still have a Senate and House of Representatives, a President, and a government.  But whether the flow of information back and forth has been hijacked by an influential few, or whether the voters' collective wisdom will rise above even this level of confusion to lead us to a better place, are open questions that only time will answer.  I just hope the answer is something we can live with.

Sources:  An article by Stephanie Bodoni carried in the Apr. 7, 2018 edition of the Austin American-Statesman entitled "Facebook to engage Europe on data scandal" was the motivation for this piece.  I also referred to Wikipedia articles on the U. S. Constitution and the First Amendment. 

Monday, April 02, 2018

The Legend of King Minsky: An AI Parable

Once upon a time, long ago but not that far away, there lived a king named Minsky.  His kingdom was prosperous and his citizens were contented, for the most part, but that was more than you could say for the king.  He had servants galore—chancellors of this and that, ladies and gentlemen in waiting, butlers, maids, footmen, all the way down to the scullery boy who carried out the trash.  But his servants never quite measured up to the king's expectations somehow.  The whole point of having servants, the king liked to say, was so you didn't have to worry about things.  He had enough to worry about already, because his wife the queen had died some time ago, leaving him with a young daughter to raise.  But the more servants he hired, the more problems he had with them.  His grand banquet was spoiled when the kitchen ran out of roast pig.  And the annual ball was a flop because the steward forgot to hire an orchestra.  So one day, when an itinerant magician came to the castle and offered to solve all the king's servant problems, the king was ready to listen.

"For one low price," the magician said, "I can give you the power to change your servants into perfectly obedient machines.  They'll look just like they do now, but you won't have to feed them or let them sleep or rest.  And they will do your every bidding exactly the way you want."

"Hmm," said the king.  "Sounds too good to be true."

"I have references!" said the magician.  And he pulled out a sheaf of letters written by kings of nearby kingdoms, some of whom King Minsky even knew.  They all swore by the magician's abilities and said they were delighted with what he was offering.

"Well, all right, how would it work?"

"We have several options."  After looking at the magician's brochure, the king chose the magic-touch option. 

"Excellent choice!  You won't be disappointed!"  And the king called for his treasurer, paid the high price asked by the magician, and duly received the power named in the contract.

Once the magician got his money, he seemed in a hurry to leave.  Before he went out the door, he called over his shoulder, "Don't forget to read the instructions!  Bye now!"  But the king never was much for reading instructions, and he couldn't wait to try out his new power.

The first place he went was the scullery, where he found the surly, dirty-faced scullery boy.  The king had never spoken to the boy and knew him only by sight.  But this time he walked right up to him and said, "Let me shake your hand!"  The boy held out a soiled hand for a handshake.

As soon as the king's hand touched the boy, something about the boy's face changed.  The surliness left it, but so did anything human.  "Boy," said the king, "I want you to wash your face and hands and do everything the cook tells you, without dawdling around."

In a toneless voice the boy replied, "Yes, Sire."  And the king was pleased to see that the change in the boy's behavior from that moment on was nothing short of miraculous.  Soon the whole kitchen was spotless because the formerly lazy scullery boy not only carried out the trash, but spent all his time cleaning up after everyone.

When he saw this change, the king couldn't wait to shake hands with the cooks and the butlers and the maids, one after the other.  The same thing happened to them.  Each one became the ideal servant.  The butler never dropped a plate again.  The cook never ran out of food, and the steward always remembered everything he needed to.  The treasurer quit making math errors in the accounts.  The king was very pleased with the results overall, although he wondered if he would miss the jokes that the treasurer was in the habit of telling.

Well, you can see where this is going.  Earlier that day, the governess had taken the king's daughter outside the castle for a picnic lunch.  The daughter's name was Persephone, and she was five years old.  Whenever Persephone saw her father, she'd raise her arms up and ask to be picked up, and he'd lift her up and put her on his shoulder for a while.  So that afternoon, the king was standing at his desk talking with the treasurer when the governess brought in Persephone.  King Minsky didn't have time to turn around before his daughter ran up behind him, saying, "Pick me up!" and grabbed him by the hand.

. . . I leave it to the reader's imagination to finish the story.  Needless to say, it doesn't end well, for either the king or his daughter.

At the present time, artificial intelligence (AI) is enjoying an unprecedented boom.  Corporations and governments worldwide are pouring billions of dollars into AI R&D, and products are hitting the market that promise to revolutionize life as we know it, from Siri-like robots to self-driving cars and more.  What the parable is intended to address is not so much any particular AI application, as it is meant to question the philosophy, mostly unspoken, on which much of AI work is based.

This philosophy treats human beings as simply "meat computers" that are no different in principle from a silicon-based computer.  The problem with this philosophy is that it is false. 

Beliefs issue in actions.  If I believe that you differ only in degree, and not in kind, from my cellphone, I am bound to treat you differently than if I believe (as I do) that there is a radical and provable fundamental difference between human beings and every other physically manifested being—animal, vegetable, or mineral.  This difference has many aspects, but in the space remaining I will concentrate on only one:  the ability of our intellects to form universal concepts. 

No computer will ever understand freedom, for example.  AI systems may some day imitate the conversation of an erudite scholar discussing freedom, but that does not mean, and cannot mean, that the computer understands the universal concept of freedom.  The proof of this point is too lengthy to give here, but is contained in Michael Augros' book The Immortal In You.  And I assure you, it is a proof that approaches the mathematical in its rigor.

Remembering this essential difference will be vital to all those who deal with AI innovations, products, and proposals in the future.  And forgetting this difference may land us in the same unenviable position King Minsky was in after his daughter grabbed his hand.

Sources:  If by some mischance you have never heard of the legend of King Midas, whose touch turned everything to gold, the Wikipedia entry about King Midas will remedy that defect in your education.  Michael Augros' The Immortal In You was published in 2017 by Ignatius Press.  For a brief summary of the argument for the immateriality of the intellect (which is why computers can't understand freedom), see the online resource by the late philosopher Mortimer Adler at  And in case you are not familiar with famous names in AI, King Minsky is named for the early AI proponent and general gadfly Marvin Minsky (1927-2016).

Monday, March 26, 2018

Self-Driving Car Kills Pedestrian

Mill Avenue near Curry Road in Tempe, Arizona is a wide four-lane surface road with few streetlights. Around 10:30 PM on the night of Sunday, March 18, it was quite dark where Elaine Hertzberg, 49, chose to walk her bicycle across the road in the middle of a block, instead of crossing at a designated crosswalk.  From a dashcam video of the accident that happened a few seconds later, it does not appear that her bicycle had any lights or reflectors on it, and she wasn't looking in the direction of oncoming traffic as she slowly rolled her bike across.

Meanwhile, in a self-driving car operated by the ride service Uber, Rafael (or Rafaela—sources differ) Vasquez, 44, was behind the wheel.  But as well-functioning self-driving vehicles tend to do, the car had driven itself so well without difficulties in the past that Vasquez had gotten used to doing things other than keeping her eyes on the road all the time.  A video of the car interior taken simultaneously with the dashcam video shows Vasquez glancing up occasionally, but most of the time she has her eyes on something in her lap—possibly a cellphone. 

Hertzberg and her bicycle were well into the car's lane before they showed up in the headlights.  But the bicyclist was moving too slowly—or the car was going too fast—for her to get out of the way before it hit her.  She died at a local hospital a short time later, becoming the first pedestrian to die in an accident involving an autonomous vehicle.

In the week just ended, several experts have criticized Uber for fielding a self-driving system that could have failed so easily.  Uber's autonomous vehicles are equipped with radars and lidars (essentially, radars using light), and should have detected Hertzberg or her bicycle before she came into view in the car's headlights.  But the video reveals no sign such as swerving or braking that the system had any sign that she was there.  And Vasquez happened to glance up only a second or two before the collision, so she was unable to do anything until it was too late.

This death both draws attention to possible defects in Uber's self-driving cars, and also calls into question the usefulness of backup drivers in such vehicles.

Most self-driving cars today are in a kind of gray area, neither completely independent of human assistance but not needing it most of the time.  In the National Highway Traffic Safety Administration's five-level classification of self-driving cars, the highest level out there according to one expert is Level 3, which says that the automated driving system (ADS) performs all driving tasks under "some circumstances," but the human driver must be prepared to take over at the request of the ADS.  I don't know about you, but I would have a lot of trouble sitting in the driver's seat and waiting for a call that might not come for hours or days.  Boredom sets in, and it's no wonder Vasquez was looking at her cellphone when she should have been watching the road.  So as long as humans are designed to be in the loop of controlling the car, the humans will have an opportunity to drop the ball, and last Sunday, that's what happened.

On the other hand, it would be hard for designers to make the leap straight from Level 0 (totally human-driven cars) to Level 5 (humans are passengers only, and the car does all the driving all the time) without months and years of real-life testing, as well as computer simulations.  And so you get into a chicken-and-egg situation:  how do you design a Level-5-competence car without testing it in real traffic, but if it's not Level 5 yet, how do you test it without a human driver to help out?  The answer is, you don't, so we have Level 2 and Level 3 cars out there with people behind the wheel, but inevitably, some of the drivers start treating the car like it was a Level 5, and you get accidents. 

This mishap will be thoroughly investigated, so it is too soon to draw any definite conclusions about the cause.  It may turn out that some of the vital systems in the Uber car were temporarily out of commission, or that the pedestrian's bicycle confused the sensors somehow, or that some other explanation is the case that we can't even imagine now.  Uber has commendably suspended all operations of their self-driving cars.  But once the cause or causes are found, the state of self-driving-car engineering can move forward with added understanding, which is how engineering usually works—learning from failures sometimes more than from successes.

It's usually dangerous to commit a known wrong in the present on the chance that it will lead to something better that might result from it in the future.  That's how we got Communism's mass slaughters in the name of the glorious egalitarian future that never came.  But there is no indication that Uber has been so negligent as to allow this accident to happen on purpose.  The first fatality involving steam locomotives didn't stop the progress of railroads, and this first fatality involving a pedestrian and a self-driving car will not stop the development of Level 5 cars, which promise eventually to reduce the already declining number of automotive deaths in both the U. S. and abroad.   It's likely that if we could give every person convicted of DWI a self-driving car right now, the net auto fatality rate might plunge significantly.  I'm not recommending that, but if we don't have the gumption to stop drunks from driving, we should take the keys out of their hands and give them to robots as soon as the market and the technology are ready. 

I'm sure that Elaine Hertzberg had no desire to become posthumously famous by being the first pedestrian to die from being hit by a self-driving car.  But now that it's happened, it's the job of engineers to make sure that more lives are saved than lost by the advancement of self-driving car technology.

Sources:  A story on this accident by Associated Press writers Tom Krisher and Jacques Billeaud was picked up by numerous outlets such as the Phoenix ABC-TV station at  I also referred to articles in the Washington Post at and Forbes at  The dashcam and interior camera videos leading up to the moment before the crash can be viewed at

Monday, March 19, 2018

The FIU Bridge Collapse: More Questions Than Answers

On Thursday, March 16, workers on a newly installed span of a pedestrian bridge across the busy seven-lane Southwest Eighth Street that divides Florida International University (FIU) from the adjacent town of Sweetwater were adjusting some tensioning cables in the span.  The Saturday before, Barnhart Crane Rigging Company had lifted the span from the side of the road where it had been built over the preceding months, carried it a short distance along the closed street, and lowered it into place successfully.  FIU officials were proud that a novel technique called accelerated bridge construction (ABC) was being used for the bridge, because the school itself has a center that promotes and studies that technique.  Instead of blocking traffic for weeks or months while hazardous lifting operations put a bridge into place piece by piece, workers using accelerated bridge construction build the bridge offline, so to speak, and then shut down traffic only briefly as entire spans are lifted into place. 

The technique has been used frequently in the last few years with no major problems, so no one expected any issues this time.  As it turns out, though, those expectations were disappointed.

At 1:47 PM Thursday, without apparent warning the entire bridge collapsed onto the busy highway, crushing cars and killing at least one construction worker who was on the bridge at the time.  Six people died in the accident. 

Some of the questions raised by this tragedy can't be answered yet.  For example:

Why wasn't the road closed during an operation such as cable tensioning that might have endangered the stability of the bridge?

The whole idea of ABC is to keep transportation going as much as possible.  Evidently the engineering firm which designed the bridge, FIGG Construction of Tallahassee, had reason to believe that the span was going to support itself safely during tensioning operations, so no one issued orders to close the road. 

What is the significance of some cracks that one engineer reported seeing on Tuesday, two days before the collapse?

Right now, we don't know.  Cracks in concrete mean that wherever the crack shows up, tensile (stretching) forces locally exceeded compressive (squeezing) forces.  Concrete is a material that can withstand a lot of compression, but hardly any tension on its own.  That's why large concrete structures contain carefully designed and placed steel reinforcement such as "rebar" and sometimes cables, which were evidently used in the ill-fated structure as well.  Some cracks are only skin-deep, so to speak, and do not indicate a structural problem, just a cosmetic one.  Others may go all the way through a structure and are signs of a major problem.  Until forensic experts piece together the remains of the 174-foot span and figure out where the trouble started, we won't know whether the cracks were superficial or significant.  At a meeting of construction personnel Thursday a couple of hours before the collapse, the cracks were discussed and the consensus was that they were not a safety issue.

If the final design of the bridge included a tower and suspension-bridge-like pipes connecting it to the span that collapsed, why weren't those parts of the structure in place before the road under the span was opened to traffic?

I am not a mechanical or civil engineer, and so I'm strictly an amateur compared to someone with professional training in those fields.  Reportedly, the university website about the bridge stated that the tower and suspension pipes were not needed for static support, and were there simply to cut down vibrations and add esthetics.  Allow this amateur to beg to differ. 

A sketch of the intended completed bridge can be viewed here, and shows that several concrete struts or trusses that connect the concrete roof of the bridge to the lower walkway part are straight in line with the planned suspension pipes.  It certainly looks like the trusses were intended to carry the weight of the walkway through tension (probably by inner tension cables) up through the roof to the suspension pipes.

It's possible (more than possible, if the FIGG engineers knew what they were doing) that even without the tower suspension structure, maintaining proper tension on cables inside the trusses would keep the whole concrete structure in compression sufficiently to counteract the tension that the walkway part would experience once it was put in place over the roadway.  What may have happened (and this is purely my speculation) is that when a construction worker began to adjust one of the tension cables, he might have done something as simple as turning a nut the wrong way.  Such an action might have sent an already marginally stable structure over the edge of failure, and once such a delicately balanced system has one part fail, the rest of it goes too.

I do not envy the work of forensic engineers who now have to transport the messy wreckage somewhere so they can pore over every identifiable piece, figuring out what was where and what the exact positions of tensioning adjustments were.  From such small details a picture should emerge that will let us figure out what went wrong last Thursday that led to such a dismal outcome of something that was supposed to be a point of pride.

In the meantime, this disaster should serve as a warning for every construction firm doing accelerated bridge construction.  Maybe we should ease off on the accelerator a little, at least until we find out what happened at FIU last week.

*NOTE added after posting:  A comment posted by the Happy Pontist, a professional bridge designer, contradicts my admittedly amateur opinion that the tower and suspension pipes might carry a load.  He confirms what the university website claims, which is that they were for vibration damping, and their alignment with the truss members was for esthetic reasons only.  Thanks to the Happy Pontist for this correction. 


Monday, March 12, 2018

Offshore Oil Regulation: Attitudes and Platitudes

The words "Be my guest," can mean different things, depending on the attitude and demeanor of the speaker.  If a host at a party says those words sincerely to invite an honored guest to open the first bottle of wine, they mean something encouraging and affirming.  But if two co-workers are discussing which one of them should go in and deliver bad news to a cranky boss, and one of them says to the other, "Be my guest" as a way of copping out, the words are meant ironically, to say the least.  So the meaning of a platitude or cliché like "Be my guest," can depend on a person's intent, and can't be discerned simply by a written record of the words spoken.  The same thing can be true of laws and regulations.

Offshore oil drilling and production can be dangerous and even deadly, as the 2010 Deepwater Horizon accident and subsequent months-long oil spill proved.  Leases of permits to drill by the U. S. federal government are made with the understanding that companies drilling and producing oil offshore (primarily in the Gulf of Mexico these days) will follow government regulations about safety and environmental protection.  Following the Deepwater Horizon spill, the Obama administration temporarily froze all drilling activities and then tightened regulations on the industry.  Work continued under those conditions, but the knowledge that the folks in charge in Washington were basically opposed to the oil and gas businesses was discouraging to those involved in them, to say the least.

A number of things have changed since 2010.  New drilling methods have forced energy prices down to about half of their former level, leading to a big decline in the drilling of new wells.  But those same new methods of enhanced extraction can be applied to existing offshore rigs, though with added difficulty, and so much of the oil and gas action in the Gulf now pertains to the aging inventory of existing rigs, some of which have stood in the water for decades. 

New York Times reporter Eric Lipton recently wrote a long profile of the industry and its fight to have some of the newer regulations modified—a fight that is showing signs of success, from the producers' point of view.  The reason that the tide has turned in the regulatory environment is, of course, the advent of the Trump administration, and the new top safety official at the Interior Department, Scott Angelle, is a good part of the reason why.

Lipton describes Angelle's political background, the main features of which are a stint as lieutenant governor of Louisiana and as a booster of the oil and gas industry, sometimes on the payroll of such companies, although he has now reportedly divested himself of any oil- and gas-related holdings.  Angelle has spent much of his time since joining the Interior Department meeting with production company representatives to see what can be done to increase production while still meeting safety requirements.

In contrast to the optimism of Angelle and the workers Lipton interviewed who are looking forward to a relief from burdensome regulations and a listless business environment, is the dark view of environmental groups and defenders of workers rights such as Lillian Espinoza-Galla, who is described as a former oil worker and is now an industry safety consultant.  It is her words which provided Lipton with his headline:  "These regulations were written with human blood." 

A chronic problem faced by those who wish to regulate any technically advanced industry is the fact that the same people who typically know the most about the industry also benefit from it financially—either directly by working in it, or indirectly by studying it or consulting for it.  And here we come up against the attitude problem again.

There are some people who can both believe in the fundamentally benign nature of an enterprise and also see how it needs to be regulated and controlled by a third party—usually the government.  I suspect Mr. Angelle may be one of these people—I hope so, anyway.  The problem that can always arise is that in paying attention to the requests of companies that want to do a dangerous thing to make money, regulators will ignore or neglect the safety and environmental "externalities"—things that workers and the rest of the world will end up paying for if something goes wrong.  This happened in a big way with the Deepwater Horizon, and Lipton describes the indifferent to poor safety track records of several of the companies that are operating older offshore rigs today.

On the other hand, there are those who believe in their heart of hearts that an entire industry should simply be wiped off the face of the earth.  When people like this are put in charge of regulating that same industry, the industry sometimes has to fight for its life, as the offshore oil business did after all offshore drilling was shut down for a few months following Deepwater Horizon.  Given the complex and inertia-laden nature of regulations, the regulatory environment can't turn on a dime.  But just as important as what the regulations are at a given time is the intent and spirit behind them. 

I see this kind of thing even in my own profession of teaching.  If an indifferent student gets encouragement from a teacher who conveys that she believes he can do better than he's doing, he sometimes surprises even himself by doing just that.  On the other hand, a teacher who decides that some students simply won't achieve anything, and conveys that message to them, well, that discouraging teacher is going to get exactly what she expects:  namely little or nothing from those students, even if the same objective teaching material comes from both types of teachers.

I am no regulatory expert, and the question of whether the changes proposed by Angelle and his Trump-administration cohorts with regard to offshore fossil-fuel activities will lead to more accidents and spills is one that I am not qualified to judge.  Maybe they will, and that would be too bad.  But at this point, what is already clear is that the attitudes in Washington toward that business have changed for the better, and there is a feeling of optimism in the Louisiana oil patch that even New York Times reporters can't ignore.  And that much seems to be a good thing.

Sources:  Eric Lipton's article headlined "Trump Rollbacks Target
Offshore Rules ‘Written With Human Blood’" appeared on Mar. 11, 2018 online at  I also referred to the Wikipedia website on the Deepwater Horizon accident.