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Software Bug Caused Qantas Airbus A330 To Nose-Dive
pdcull writes "According to Stuff.co.nz, the Australian Transport Safety Board found that a software bug was responsible for a Qantas Airbus A330 nose-diving twice while at cruising altitude, injuring 12 people seriously and causing 39 to be taken to the hospital. The event, which happened three years ago, was found to be caused by an airspeed sensor malfunction, linked to a bug in an algorithm which 'translated the sensors' data into actions, where the flight control computer could put the plane into a nosedive using bad data from just one sensor.' A software update was installed in November 2009, and the ATSB concluded that 'as a result of this redesign, passengers, crew and operators can be confident that the same type of accident will not reoccur.' I can't help wondering just how a piece of code, which presumably didn't test its input data for validity before acting on it, could become part of a modern jet's onboard software suite?"
sure, but the number of accidents will likely still be fewer than those caused by human drivers.
Cant be worse then the drivers out there.
"Have you ever thought about just turning off the TV, sitting down with your kids, and hitting them?"
This, from the same company, while building the A380 megajet decided to upgrade half of their facilities to plant software version 5, while the other half decided to stick with version 3/4. And did not make the file formats compatible between the two versions, resulting in multi-month delays of production as a result.
Point being, in huge projects, simple things get overlooked (with catastrophic results). My favorite is when we slammed a $20 million NASA/ESA probe in to the surface of mars at high speed because some engineer forgot to convert mph in to kph (or vice-versa).
moox. for a new generation.
There were people against airbags, too, because they killed some people who otherwise wouldn't have died. You work on fixing those things. But whether the system as a whole is worthwhile is judged on whether it saves more than it kills.
Are you seriously accusing Google of being malicious in developing a driver-less car? Do they have a stake in keeping the population numbers down or something?
While I agree that software will never be bug free, it will quite possibly save many more lives as human drivers are terrible. They are prone to panicking under pressure, misjudging distances, unable to handle a car as efficiently as possible, take too many risks (swerving in and out of traffic, following too close), drive under the influence of drugs and alcohol, get distracted by phones, screaming kids among many other things that well written and tested software could do better.
Do you also want pilots to fly planes manually at all times and remove auto-pilot since software can never be perfect?
I know, those evil monsters and their want to improve the lives of people by inventing things. Since there might possibly be a bug that may cause issues they should just stop and throw in the towel right? I mean humans are perfect drivers as is so why fix something that's not broken.
"I can't help wondering just how could a piece of code, which presumable didn't test its' input data for validity before acting on it, become part of a modern jet's onboard software suit?""
How about reading the darned final report, conveniently linked in your own blurb? There was lots of validity checking. In fact, some of it was relatively recently changed, and that accidentally introduced this failure mode (the 1.2-second data spike holdover). (Also, how about someone spell-checking submissions?)
Even on the road today this is an issue. Doesn't matter how good of a driver you are. If one other idiot on the road is driving crazy, you could get killed no matter how you drive. Weakest link and all that...
"Freedom in the USA is not the ability to do what you want. It is the ability to stop others from doing what THEY want"
Which is actually Airbus relies on sensor input over the "pilot". Boeing believes in the opposite. I'm inclined to believe Airbus in that the majority of accidents are human error over computer error.
The problem with aviation accidents is the relatively small sample size. With cars there will be much better data (i.e. more data points).
If anything computer driven cars will be better - since due to the safety "fears" like the OP, they will be programmed to be cautious. They have to be better at handling conditions than human operators, otherwise it's instant blame. They have to be better to the degree that you can blow the stats out of the water. e.g. When the first computer driven car hits a person, they need to say "well based on hours on the road, if it was human driving this it would have hit 30 kids by now".
It's so interesting to see people's reaction to the whole driver-less car thing. It's incredible to see the kind of ethical thought-experiment that must necessarily go through everyone's mind when they come to this conclusion: How many lives must be saved before I will tolerate someone being brutally slain by a malfunctioning computer?
Every day, children are run down by drivers who are not paying attention, tired, drunk, or just plain don't have time to react. Since a driver-less car is incapable of being drunk, tired, or distracted, then it's a safe bet that they'll be much better at avoiding those accidents that can be avoided. But the reality is that the latter scenario (no time to react) would still lead to the deaths of many children (and others!).
At what point does it become "worth it"? When the driver-less car causes 1/10th as many fatalities? 1/100th? 1/1,000th? How many human deaths must be prevented by letting computers drive cars before we're willing to accept 1 single death by those same computers?
It's a real-life example of the "Trolley Problem"
http://en.wikipedia.org/wiki/Trolley_problem
nothing in software is ever free of bugs. just because it's a bug-fix doesn't preclude the possibility of the bug-fix itself (or its side effects) from introducing new bugs, or being an incomplete fix which just happens to pass whatever inadequate test was thrown at it.
have you SEEN the way meatware AI operates a car? At least a google driverless car would use its turn signal before suddenly jerking into a turn and trying to kill me on a bike with a right hook.
Speaking of faulty sensors, that's pretty much what goes down when meatware AI has a certain alcohol content. Or uses a cellphone. Or eats fast food. Or puts on makeup. Or deals with newer meatware instances in the back seat. Or looks down to adjust the radio. Or falls alseep. Or is distracted in thought. Or....
Your post is full of FUD. A million people die annually because of human drivers. A driverless car killing half that many would still be an improvement.
www.un.org/ar/roadsafety/pdf/roadsafetyreport.pdf
What are you? some kind of person that doesn't read the actual articles or documents? Oh wait.. this is slashdot. Here let me copy paste some text for you
So there you go, there actually really was validity checking performed. Multiple times per second in fact, by three separate, redundant systems. Unfortunately all 3 systems had the bug. Here is the concise summary for you:
I don't need to test my programs.. I have an error correcting modem.
yup. all the while forgetting that the while altimeter shows altitude, it rarely actually measures distance to the ground, it measures air pressure, and then assumes an aweful lot.
done much driving lately?
even if MS wrote the software, it'd definitely be well in the top 2 percentile as far as driving skills go.
see how input data validation works in your brain when you're tired, drunk or just distracted?
This is such a common fallacy -- we would expect an AI driver to be fucking perfect before we would ever call it "safe". Sure, they will have bugs, and people will die. But they will have nowhere near as many bugs as the meat computer that we have in our heads. Amazing as it is, the human brain is simply not meant for the types of tasks that we often apply it to, and as such, tens of thousands of people die on the road each year. Even if the adoption of driverless cars cut that down to 1% of the current death rate, people would still be screaming about the cars killing us. George Carlin was right; some people are really fuckin' stupid.
To the haters: You can't win. If you mod me down, I shall become more powerful than you could possibly imagine
the idea that a bunch of automatically piloted vehicles is somehow a better solution to city transport than mass-transit, it boggles my mind.
real people do not have money to maintain their cars properly. things are going to break. there are not going to be 'system administrators' to fix all the glitches that come up when cars start breaking down after a few years.
there will be problems. do i know which problems? no, but i know the main problem.
arrogance amongst revolutionaries. it is historically a pattern of the human species. declaring that nothing could go wrong is usually a precursor to a lot of things going wrong. not because the situation was unpredictable, but because human beings in an arrogant mindset tend to make a lot of mistakes, be reckless, and try to cover their asses when things go wrong.
but successful engineering is the anti-thesis of arrogance. nobody worth his salt is going to say 'what could go wrong'? they are going to have a list of 500 things that could go wrong, and all the ways they have tried to counter-act those wrong things happening.
It's bad idea for a specific reason.
There are two "brains" that can operate the car. Google can make a pretty decent brain, but it is not going to come remotely close (in any way) to the human brain in terms of its ability to perceive the environment (sensors), make sense of it (pattern recognition), and put it all into context (experience, extrapolation).
Google will excel in reaction times and advanced planning. Through Google it will be possible to mitigate traffic by solving a very human problem, which is cooperation towards a common goal. Google could react faster, and with less overcompensation, to a car drifting into its lane.
Where Google will fall far short is recognizing the road rage in the driver next to it (beating his hands on the steering wheel and screaming), the lack of concentration (woman putting her lipstick on), etc. Putting those things in context and assigning risk to drivers next to you is not something Google will be able to do from its sensors. However, even the average driver is getting cues in so many ways about what is really going on around them.
The reason why it is a bad idea, is that while Google is operating, the human brain is off. It's not instant-on either. Driving is a constant level of concentration, even when it seems like you are doing it "subconsciously". From start to finish, the average driver is pretty aware of their surroundings and processing an impressive amount of data. A human brain will beat Google every time on those terms.
When Google fails, or "judges" the environment poorly, how quickly can the human brain come back online, evaluate the current environment, take control, and make the required adjustments?
Until the Google brain is able to fully replace a human brain, it is not a good idea to involve the two in a hybrid system. The lag between the two systems taking control from one another is just too great.
Self-parking is fine, and limited operations involving high efficiency traffic lanes where human control is not permitted will be fine. As long as the transition into those operations is in a time frame a human can deal with.
Example being, the human brain pulls the car along the high efficiency traffic lane, "tags" the Google brain in to insert itself into the traffic. The Google brain then notifies the driver and validates proper control and awareness before exiting the traffic and turning control over to the human driver. Failure means Google pulls the car to the left in the emergency lane and brings the car to a full stop.
Any other kind of operations just seems fundamentally unwise to me because of the hybrid nature and inherent limitations of Google's AI, advanced as it may be for now.
My threshold for letting a computer operate a car no differently than a human, is the computer can meet or exceed the human's ability in every respect. That is not true right now, and will not be true for decades.
You may trust a Google car more than the average driver, but that is only really true if the Google car also has no driver.
Which is actually Airbus relies on sensor input over the "pilot". Boeing believes in the opposite. I'm inclined to believe Airbus in that the majority of accidents are human error over computer error.
Sometime in a flight like AF447 the computer doesn't know jack either and gives up the ghost. In the AF477 flight(equipment airbus A330), apparently, the pitot sensors gave inconsistent readings and the autopilot disengaged. What insued was apparently what can happen when you have pilots that are error prone and a computer that doesn't know what the hell to do to help them. In these situations, I think it's prudent to still have a system that defaults to the pilot as if they knew what to do when they know the sensors have crapped out and apparently even Airbus agrees with this. Unfortunatly, it appears that the AF447 pilots were not up to the challenge in this circumstance.
Clearly the solution is that I, as the only decent driver around, will be the only person allowed to drive myself, while everybody else must be using these Google cars.
A good driver, by definition, mitigates the bad driver by taking appropriate actions to reduce the risk. It is not how you drive, its how you manager the drivers around you that makes you a good driver.
And that would make it different than today when i nearly got ran over by a moron playing with his cell....how exactly? when I was a kid we were taught "This is a 2000 pound weapon, you treat it like a weapon and respect it or someone could die, maybe you, maybe someone else" and even then we still liked to drive fast but today? Jesus tap dancing christ I've not seen a bigger bunch of dipshits in my entire life than what I see on the road every damned day! Dipshit men playing with their phones, dipshit women putting on makeup AND playing with their phones, its like moron bumper cars out there pal!
That is why the other day when I saw my oldest a couple of car lengths ahead of me (and I knew he couldn't see me from where i was at) and saw him pull over into a lot and get out i just had to pull in behind him. I just knew why he had pulled in but when I asked him and he said "Somebody called me so i was pulling over so I could return the call" i immediately pulled out a twenty and handed it to him, saying "Having a brain is a damned rare thing in this world, smarts should be rewarded".
Frankly i'm all for Google car because at its worst it can't be as dangerous as the braintrusts on our roads. With my oldest taking 18 hours next semester its not HIS driving I worry about every day, its the dipshits with too many toys and not enough functional brain cells. If the Google car takes the keys away from even 20% of these numbnuts frankly the accidents will plummet, and that can only be of the good.
ACs don't waste your time replying, your posts are never seen by me.
DISCLAIMER: I hate air travel, but do it most weeks.
I have worked in and around the safety critical software industry for over 20 years. The level of testing and certification that the flight control software for a commercial aircraft is subjected to far exceeds any other industry I'm familiar with. (I'm willing to be educated on nuclear power control software however.)
The actual problem on the Qantas jet was a latent defect that was exposed by a software upgrade to another system. So the bug was there for a long time and I'm sure there are still others waiting to be found. But this doesn't stop me getting on a jet at least twice a week.
As a software professional and nervous flyer, do problems with the aircraft software scare me? No not really. What scares me is the airline outsourcing maintenance to the lowest bidder in China, the pilots not getting enough break time, the idiotic military pilot who ignores airspace protocol, and the lack of english language skills in air traffic controllers and cockpit crew across the region where I fly (English is the international standard for Air Traffic Control).
A good friend is a senior training captain on A330's, and in all the stories he tells software is barely mentioned. What get's priority in the war-stories is the human factors and general equipment issues - dead nav aids, dodgy radios, stupid military pilots. One software story was an Airbus A320 losing 2 1/2 out of 3 screens immediately after takeoff from the old Hong Kong airport. The instructions on how to clear the alarm condition and perform a reset were on the "dead" bottom half of one of the screens.
A great example of software doing it's job is the TCAS system - Traffic Collision Avoidance System (http://en.wikipedia.org/wiki/Traffic_collision_avoidance_system). To quote my friend "If it had lips, he'd kiss it". It's saved his life, and the lives of 100's of passengers, at least twice. Both times through basic human error on the part of the pilot of the other aircraft.
One final thought - on average about 1000 people die in commercial aviation incidents each year world wide (source: aviation-safety.net) . In the USA, over 30,000 people die in vehicle accidents every year.
I think you're looking at it all wrong. This has nothing to do with a comparative death ratios. This has everything to do with liability. At the end of the day, people want a legitimate target to point their finger at regardless of the fact injury or death could have been prevented. If people are allowed to take Google to court and render justice, then I'm sure this new automated driving technology would be ok in their minds. OTOH, if Google is given sanctuary from public lawsuits, hell no!
Life is not for the lazy.
Yep, my wife got hit by a semi while sitting stopped at a red light.
That same could be said for every other part of the plane. The story sounds made up. By you, your lecturer, or the engineers themselves, who knows.
Posting anon because I moderated.
I had a very similar problem once with firmware on a TI DSP. The symptom was that a peltier element for controling laser temperature would sometimes freak out and start burning so hot that the solder melted. After some debugging, it turned out that somewhere between the EEPROM holding the setpoint, and the AD converter, the setpoint value got corrupted.
The cause turned out to be a 32 variable that was un-initialized, but always set to 0 by the stack initialization code.
Only the first 16 bits were filled in because that was the value stored in the EEPROM. The programming bug was that the other 16 bits were left as is. In >99% of the time, this was not a problem. But if a specific interrupt happened at exactly the wrong moment during initialization of the stack variable, that variable was filled with garbage from an interrupt register value. Since the calculations for the setpoint used the entire 32 bits (it was integer math) it came out with a ridiculously high setpoint.
Having had to debug that, I know how hard it can be if your bug depends on what is going on inside the CPU or related to interrupts.
There may only be a window of less a micro second for this bug to happen, so reproduction could be nigh on impossible.
It's not about choosing one or the other, but hybrid systems operating at the same time.
If you are going to compare quality, the human will win every time. We can give anecdotal evidence about how bad drivers are, but statistics show that driving is not so dangerous that we need to consider stopping it altogether. Really think about it for a second. During your average day, how many really bad drivers did you personally interact with that created a dangerous situation resulting in an accident? Pretty low huh? I would expect so, otherwise insurance would cost thousands and thousands per month, instead of per year.
Humans are not the inferior solution overall right now. Not by far.
It is also not because Google is not perfect either. Specifically, it is because of the time required, and the complexity of shifting control from Google to the driver. Once such a system becomes normal to a driver, their attention is not going to be on the road, but on their interaction with other devices. You cannot reasonably expect a person to be in complete awareness, hands at 10-2, ready in a split second to take control. You would get too bored without immediate feedback, your mind would drift. This would be completely normal too.
This is not to say that the system itself might not be useful, but it would have to be under very controlled conditions excluding human drivers altogether. It could work, provided the shifting of control was at a controlled rate in relatively controlled conditions. Give the human being time to adapt and obtain situational awareness.
As cool as this sounds, it is just not ready to fully replace a human, unless it could perform at a human level or better. The dream of a car that can drive itself completely under all conditions is still some ways away.
The idea of changing carpool lanes over to high efficiency lanes where human control is not allowed seems like a more pragmatic approach that decreases the complexity and uncertainty that the Google system has to deal with. It has very high value as well since it can optimize traffic patterns far better than a human simply because it can cooperate with a much larger number of cars over greater distances. A human could never hope to do that with our inherent limitations.
That system could realize some serious fuel savings and increase productivity by essentially mimicking an airplane in auto pilot mode. The human is really just there to get the system to the point where it can safely transition in and out of a computer controlled lane. That will be extremely advantageous to overall traffic.
This type of story isn't new and i'd imagine its pretty common. When you know there are corner case bugs unpatched that were only 1 in 10,000,000 chance of being triggered in a given flight, do you still want to risk relying on your software for your life or death? Nah. What those engineers weren't doing was listening to the Boeing engineer's list of bugs and that they'd be doing the exact same thing whenever a new system's hot off the assembly line.
We have computer controlled trains in my city, and the rumor mill kept chupring away that the engineers would never touch them with a ten foot pole, but to my knowledge there's never been a serious derailment or automation related fatalities (lots of jumpers sadly, but I guess that comes with the territory).
Bye!
It looked like half of one 32-bit word was combined with half of another 32-bit word during queue assembly on at least some occasions. But there are errors not explained by that.
This is why I like fuzzing. Sending random and/or corrupted data to software to evaluate the software's robustness and sensitivity to corrupted inputs. For a project like this I would like to send simulated inputs from regression tests and recorded data from actual flights to the software while fuzzing each playback, repeat. Let a system sit in the corner running such tests 24/7.
In theory some permutation of the data should eventually resemble what you describe.
The Airbus will also change the throttle to the engines without moving the throttle levers whereas the Boeing will move the levers to where the computer set the throttle, When the autopilot takes a crap and you put your hands on the throttle, you must remember that the controls are lying to you and act accordingly.
Speaking as a pilot, I care a great deal where I am right now because it may affect whether I'm going to hit another plane. I've been close enough to see the crew of another plane and felt safe because I first spotted him nearly two miles out and knew where he was the whole time, and I've leveled off out of a take-off to see another plane inside of a quarter mile and was shaken by the experience. I know that a quarter mile seems like a long way, but when converging airspeeds are in the range of 150 knots, there's very little time between seeing him and a collision, and I want to know when someone is passing 500 feet above or below me or is on a potential collision course.
We maintain distance (something that falls into your definition of "everything else") for a reason. My plane's max cruising speed is only about 130 knots, but the Baron over there has a max speed in excess of 200 knots. If we're both tooling around max and closing on reciprocal courses, that's a potential closing speed of 235 knots--4.5 miles per minute. If we're two miles apart, we have less than 30 seconds to see each other and properly maneuver. I've also had a plane pass over me close enough that I could hear his engine over mine, and that's the last time I want to hear that sound.
I measure where I am because that is by far the most important. Where I will be is secondary. The basic rules of piloting: Aviate, navigate, communicate. Fly the plane as it is, figure out where you're going, tell someone where you're going. Notice that the first is where I am right now. The second one deals with where I'm going to be, because I almost always have options, even if it means turning around and going back where I came from.
You're either not a pilot, or one who I don't want to be within 100NM of.
You can never go home again... but I guess you can shop there.
Back in my Finnish Air Force days I talked to a captain who had flown the F-18C in his last three active flight years. He told that when you're straight and level in the Hornet and peek over your shoulder you probably see the ailerons swaying back and forth as the computer tries to keep the plane stable.
Interesting here would be some statistics. How many Boeings have come into serious trouble, and how many Airbuses?
Besides the GP's point about Airbus pilots being unable to override the computer being complete and utter bollocks (Airbus' still have a analouge actuator control (Electronic) in them), there have been a few near misses which if it were not possible to take manual control would have resulted in a crash such as the JetBlue landing at LAX in 05.
On the other hand, there have been incidences with Boeing aircraft which are believed would have been solved by automated systems such as AA flight 965 (Colombia 1995) where if the airbrake was automatically retracted the pilot would have been able to climb a way safely.
Here is a good post on the subject. According to the ASTB who conducted the investigation there have only been 3 such incidents in 128 Million hours of A330 operation as of 2008. That is a damn good rate of failure wouldn't you say? Pilot error being the cause of approx 48% of all accidents, Airbus or Boeing. Modern aircraft are getting safer all the time, they see more mechanics and engineers in a week then your car will see in its entire lifetime. Everything is checked and double checked, anything suspicious gets replaced. I never think I'm in danger stepping onto an an Airbus or Boeing aircraft.
The whole Airbus Vs Boeing argument is a dick pulling contest between biased pilots. It's like a Xbox/PS3 fanboy war. Utterly senseless to third party observers (and bronzed fingered PC gamers) Now amongst the 25 worst airlines you have a 1 in 850,000 chance of dying and I dont fly any of those airlines (1 in 9.2 million for the 25 best), hence my practice of congratulating myself at the check in counter as I've survived the most dangerous part of air travel, the drive to the airport. Compared to our road toll, our air toll is minuscule.
Calling someone a "hater" only means you can not rationally rebut their argument.
What a load of uninformed bullshit - Airbus has several levels of computer control, called laws, one of which is Direct Law which passes all inputs directly to the control surfaces. And if that isn't enough, they have mechanical backup controls for all surfaces on the flight deck, so even with a completely dead computer the aircraft is still flyable.
You sir, are talking complete shit, but that seems to be normal when someone wants to put Boeing on a pedestal over Airbus.
Let's go over some of your "mistakes"...
The 787 isn't Boeings first FBW aircraft, they have had one flying since the mid 1990s with the 777. The 787s system is an evolution of the 777s.
AF447 didn't crash because of a computer problem, it crashed because of poor crew relationships in the cockpit - three pilots in that cockpit and not one was interested in what the others were doing. They didn't run basic check lists, they ignored other information, and the pilot flying did completely the wrong thing - the situation was completely survivable if they had carried out the correct procedures, except they didn't. The crash wasn't caused by the computer, it was caused by the pilot taking a stable aircraft and stalling it badly when nothing about the computer error forced him to do that.
Okay, a few facts, the A330 is fly by wire, this means between pilot and control surfaces everything must go through the avionics, if the avionics totally fails then that plane is by definition little more than a glorified missile.
That said, it seems the backups and pilot responded exactly as they should have in this case. The plane pitched, enough to throw the passengers around and cause injuries, pilot disengaged autopilot and corrected, declared an emergency and safely landed at the nearest big enough airport.
Please tell me how he did anything wrong? Please tell me how the rest of the computer systems failed to cause and actual crash Nope neither, the plane was left in one piece on the ground.
The only thing I say is, why did it take Airbus 2 years to find and fix that major bug?
Except that the designers of the software didn't take all possible situations into account. For example, any Fly By Wire Airbus will automatically pitch up if speed increases too far above the maximum airspeed, even when flown manually. This may be a good idea when the airplane is diving (the most likely cause for overspeed), but not when it's straight and level with other traffic immediately above! This has already made several Airbus planes in heavy turbulence suddenly start to climb violently due to a sudden change in airspeed or temperature and overriding the pilot's MANUAL inputs while he's trying to avoid flying into other traffic! That's insane, and it's only one of many reasons why I can't wait to get off the Airbus fleet onto a more sensibly designed plane. (I'm currently an A320 pilot).
Except that the designers of the software didn't take all possible situations into account. For example, any Fly By Wire Airbus will automatically pitch up if speed increases too far above the maximum airspeed, even when flown manually. This may be a good idea when the airplane is diving (the most likely cause for overspeed), but not when it's straight and level with other traffic immediately above!
Except if that other traffic is also an Airbus.
Even on the road today this is an issue. Doesn't matter how good of a driver you are. If one other idiot on the road is driving crazy, you could get killed no matter how you drive. Weakest link and all that...
Everyone who drives faster than me is a maniac. Everyone who drives slower is an idiot.
It is dangerous to be right when the government is wrong.
So how will you reduce the risk of someone next to you suddenly deciding to switch the lanes without checking that you're there? How do you reduce the risk of someone deciding he just has to pass the car in front of him even when there's incoming traffick? How do reduce the risk of someone deciding to test his engine and losing control?
It doesn't matter how good a driver you are; if someone else screws up bad enough, you're dead.
Forget magic. Any technology distinguishable from divine power is insufficiently advanced.
So how will you reduce the risk of someone next to you suddenly deciding to switch the lanes without checking that you're there? ...
You reduce that risk by not staying next to another driver any longer than you have to.
You watch the drivers around you and anticipate what stupid things they might do that would endanger you. Then you decide what actions you need to take to minimize that risk. Then you take those actions. That's what defensive driving is all about.
It's not easy and can't really be done while jabbering on the phone. And it's not very satisfying to the ego to drop behind another driver who is a little more aggressive than you, but it can pay out in reduction of accidents caused bu others.
Yes, I'm sure one can point out situations where there is little to no opportunity to avoid the actions of others, but in far more situations there is plenty of opportunity to minimize the risks due to other driver's stupidity.
Sure - the flight in question was British Midland Flight 92.
The situation I mentioned came about because the pilots shut down the right engine due to vibration and presence of smoke in the cabin - up to the 737NG line cabin air was only taken from the right engine, so thus engine vibration and smoke in the cabin meant the right engine was at issue. However, in this case it was the left engine which had actually failed.
While the left engine was failing, the autothrottle automatically adjusted the fuel flow into it in order to maintain the thrust levels from it - this had the effect of causing an asymmetric thrust selection between the left and right engines - however, the throttle lever actuator only selected a physical position for the right hand engine at its lower thrust level, meaning the autothrottle was actually selecting a higher value which was not indicated in the positions of the throttles (the two throttle levers are linked by one actuator when under autothrottle control, thus they can actually only show the thrust level of one of the engines - in this case, the right engine).
When the pilots turned off the autothrottle to power down the right engine, the left engines selected thrust returned to that of the physical position of its thrust lever - which had the effect of reducing the vibration to the point where the flight crew thought they had indeed turned off the correct engine when they shut down the right engine.
When they were on approach to Midlands Airport, they increased thrust on the left engine, which caused it to fail completely and thus the aircraft crashed short on approach.
This system was highlighted in the crash report, along with a number of other issues with the 737NG design - Boeing did infact have to ground a large number of aircraft before the solution was deployed to the delivered fleet. It was not the sole cause of the crash, but it was something that was heavily highlighted in the chain of events.