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Computers Key To Air France Crash
Michael_Curator writes "It's no secret that commercial airplanes are heavily computerized, but as the mystery of Air France Flight 447 unfolds, we need to come to grips with the fact that in many cases, airline pilots' hands are tied when it comes to responding effectively to an emergency situation. Boeing planes allow pilots to take over from computers during emergency situations, Airbus planes do not. It's not a design flaw — it's a philosophical divide. It's essentially a question of what do you trust most: a human being's ingenuity or a computer's infinitely faster access and reaction to information. It's not surprising that an American company errs on the side of individual freedom while a European company is more inclined to favor an approach that relies on systems. As passengers, we should have the right to ask whether we're putting our lives in the hands of a computer rather than the battle-tested pilot sitting up front, and we should have right to deplane if we don't like the answer."
It's not surprising that an American company errs on the side of individual freedom while a European company is more inclined to favor an approach that relies on systems.
How fond Americans are of reductionist dualities that are unhelpful, misleading and frequently downright dangerous: American pilot with The Right Stuff in an American plane would have saved everyone; dangerous European plane and computer killed hundreds. Oversimplified sniping, or childish fantasy?
If I want real facts on flying, instead of wild-assed pseudo-political trollery, I'll go read Peter Ladkin or Patrick Smith: "The gist of the accident appears pretty clear: Air France Flight 447 was victimized by a terrible storm."
you had me at #!
What a dumb phrase. Do you only want former airforce pilots who've actually seen combat flying commercial planes? How exactly is that going to keep you up in the air in a civilian airliner experiencing an electronic or mechanical malfunction?
And if what you really mean is experienced pilots, what about some pilot who's been flying for years and has never had an emergency situation and then makes a mistake and then (s)he makes a judgement error in a critical situation? Are you then going to call for the iron calm of a computer rather than a fallible human pilot?
No, the answer is statistics. What's safer and more reliable in the long run? How many crashes have we had due to computer error rather than human error given x hours flown by each?
The very wording of this ridiculous post presupposes an answer. And in the future it is very likely the wrong answer. Sure computers will make errors. But in general people will make them more often, and computers are just going to get better.
And casting this as some kind of bizarre collectivist vs. individualist ideology debate is ridiculous as well. What does towing some ideological line have to do with safely getting to your destination in an airplane?
This Slashdot article is full of simplistic drivel designed to provoke ideologically based knee-jerk responses instead of any kind of reasoned debate.
The linked to text is much, much better, even though offering people a choice is problematic given how the whole non-refundable ticket system and airline logistics systems currently work, not to mention that making a choice at the gate when you get on the plane will throw off your schedule.
Need a Python, C++, Unix, Linux develop
"What are you doing Dave?"
Be you Admins? nay, we are but lusers!
Lemme' guess... you're an American.
"In prison you just have to shut your eyes and take it. Here you have to shut your eyes and give it."
when James T. Kirk has the conn. He doesn't believe in a no-win scenario!
The Continental flight that crashed in Buffalo on the 12th of February crashed because the inexperienced pilot pulled up when the plane stalled. A computer controlled system might have nosed down to get airspeed and saved 50 lives. Of course I doubt a computer controlled system would be able to make a flawless landing in the Hudson.
Well it's quite simple really. Boeing doesn't expect anybody to be flying one of their big jets without years of experience. If you have a mechanical failure do you really want to have a machine, that may be getting fed bad data, trying to figure out what to do next. (Also doesn't help airbus that they seem to be having many more crashes then Boeing over the last five years).
What a dumb phrase. Do you only want former airforce pilots who've actually seen combat flying commercial planes?.
Who wouldnt want to be on a commercial flight where random barrel rolls, climbs and dives occur?
Be you Admins? nay, we are but lusers!
I trust an engineer's years or study and careful planning over a pilot's hastily considered last-second decisions. It's not that I don't trust the pilots, it's just that an engineer has had more time to put together a solution and implement it in the computer. They know the limits of their craft intimately and I trust them to know how to keep them in the air.
Scientists point out problems, engineers fix them
altslashdot.org: The future of slashdot.
No, the answer is statistics. What's safer and more reliable in the long run? How many crashes have we had due to computer error rather than human error given x hours flown by each?
Statistics is only the answer if it measures the right thing. At a minimum your suggestion doesn't qualify because computers fly planes on autopilot almost all of the time anyway. Sure there are better statistics to be looking at, I can think of a few myself off the cuff, but better than junk doesn't mean good or useful.
So beware the fallacy that we do know the answer, it may ultimately be that we are simply incapable of measuring the correct variables to make a mathematically sound evaluation.
When information is power, privacy is freedom.
It's not surprising that an American company errs on the side of individual freedom...
Eh? You mean the freedom to work under-paid pilots 14-16 hours a day like Colgan Air? And the FAA let them slide because Colgan had friends in that office? Some of their pilots could make more flipping burgers. Like the pair that were tired, under-paid and not paying attention who turned Continential flight 3407 into a giant lawn dart.
This isn't political. I don't care if it's human, machine or a trained goat. Whatever gets the aircraft down in one piece is what I want managing the control surfaces.
That's our life, the big wheel of shit. - The Fat Man, Blue Tango Salvage
Boeing's manual mode causes 100% fatality when the pitot tubes are blocked, too.
What a shitty article considering that took me 30 seconds to research and wasn't mentioned.
"If the Gimli Glider or Flight 1549 had been on an Airbus, there would have been a lot of dead people"....
fyi- Flight 1549 was an Airbus A320. Perhaps you would like to rethink your conclusion?
I'm a pilot, and I fly both Boeing and Airbus planes, quite often at night, when its really windy. I've watched the news and seen the preliminary reports, and it is clear to me that the Air France crash was caused by icicles forming on the propellors, making them get stuck. With such a reduction in thrust, the plane would have been in danger of stalling. The common procedure in this situation, which I have followed on a number of occasions, is to put the plane into a steep nosedive to regain some speed, before using full thrust to get back up to the desired height.
There is no doubt that the Air France pilots put the plane into a near vertical dive, as required by procedure, but then hit some waves on the sea before they could pull out. Once they find the black box then we will know for sure, but for now this is the most likely answer.
ummmm Flight 1549 was an Airbus 320.
American Aircraft don't always have manual overrides, and EU (UK, German, French) aircraft often don't lack it. In fact Airbus is its own company and as such follows its own principles as far as design goes. Right now they're designing their aircraft to be as simple as possible and want to eliminate a lot of the human element.
I don't agree with a lot of the discussions Airbus has made over the years:
- Low strength materials in key areas
- No warning alarm when auto-pilot is disengaged
- Less manual control in case of system failure
But then again Boeing has made some HUGE errors and has updated their 747 thousands of times to fix design flaws. People forget that not only is Boeing an older company but a lot of their aircraft designs are up to 40 years old and have been evolving constantly.
American Vs. EU is complete bs but whatever helps Americans sleep at night.
First, I would say it naive to think that computers are somehow at fault, and that they do not have a net benefit. The main reason to use digital solid state computers is that they often reduce discrete component count, which usually increases reliability. In a system that is supposed to nearly 100% reliability, like an aircraft, component count must be kept to a minimum. That has traditionally mean fly by wire, and the more fly by wire, the better. My understanding is that Airbus reduces complexity significantly assuming a complete fly by wire profile. One could, for instance, install backup hydraulics, which I assume is not done, but this would reduce reliability.
There is not simple solution. Things do not increase security and reliability simply because we feel better. For instance, Many people feel safer in big trucks but many studies have shown that one is safer in a full size sedan. Likewise, one thing that makes a large truck, especially an SUV safe is the electronic stability control, which can countermand any driver instruction. Large planes are already computer controlled. Long haul flying of large planes is in no way a trivial task. I agree with the blog mentioned in the article that people who have no experience have no basis to make any useful comment.
"She's a scientist and a lesbian. She's not going to let it slide." Orphan Black
Summary states:
Boeing planes allow pilots to take over from computers during emergency situations, Airbus planes do not.
According to this link, the Airbus does, in fact, have a manual override mode.
Which would make the argument as presented a moot point.
"But it's time the airline industry stopped treating passengers like children and began informing us of what airplanes we're flying on and how they're flown--and allowing us to decide how we're taking our lives in our hands." Really? These are complex systems with multiple levels of functionality and are difficult to understand. From the article, the author clearly lacks knowledge on the subject. Furthermore, I don't think the average person really wants to know how the plane works anymore than they want to know how CAN communication makes the EFI system in their car work by integrating ECU communication. As a consumer, I just want the car to start when I turn the key without it blowing up in my face.
While it's true that starting pay is low, it's not in the $15K range; more like $20-$25K. But it's also true that that you don't stay in that pay range for long. See here.Your post is very misleading. Average pay and starting pay are very different things!
I come from a family of pilots (IANAP), and they all live quite well. The low pay is a known problem, because many pilots do extra duty to make ends meet, but it also has the effect of encouraging only the truly motivated ones to stick around.
<loaded question>How much do military pilots make? Do you feel unsafe with them?</loaded question>
A gazillion years ago, I rode on some airline (Muse? Love? Some weird four letter name) about two days before they were scheduled to shut down, and I guess the pilot just felt like flying figure-8s over the Grand Canyon ("bad weather in Las Vegas", yeah, right).
It was really something, a view like you would not believe, and if we had not been doing our figure-8s over something that impressive, I would have been really pissed, because my tummy was also doing figure-8s.
If the Gimli Glider or Flight 1549 had been on an Airbus, there would have been a lot of dead people. When something goes wrong, Rule 1 is FLY THE FUCKING PLANE. Well, if the computers fail on an Airbus, good luck flying it!
Flight 1549 was an Airbus A320. Don't fall for the FUD, any large passenger airliner is going to be designed to be as survivable as possible in the event of power loss. This whole article is just another example of irrational hysteria.
"We have to go forth and crush every world view that doesn't believe in tolerance and free speech." - David Brin
...of crashes due to computer error and pilot errors in crashes covered in episodes of Air Crash Investigations (Mayday).
http://en.wikipedia.org/wiki/List_of_Mayday_episodes
Hint: There were no crashes due to computer error.
Mit der Dummheit kämpfen Götter selbst vergebens
You're joking, right?
A very similar incident to the Gimli Glider did happen. I'd refer you to Air Transat flight 236, an Airbus A330 that ran out of fuel over the Atlantic Ocean and glided to a successful landing at Lajes Air Force Base in the Azores.
And Flight 1549? That was an Airbus A320.
As to your last statement, if you understand the Airbus flight control laws you'll know that with the landing gear down in that type of situation, you'll be in direct law, which does not modify any pilot control inputs before being sent to the flight controls. Even if it had degraded all the way to mechanical backup (none of the 5 computers operational), you'd still have the use of pitch trim and rudder.
Boeing and Airbus have had roughly identical numbers of crashes in recent years. Boeing has had just a fraction more. If one method of flying was better than the other, there would be a difference, right? Since there is no measurable difference, it follows that the differences in a crisis balance out. What is good for one sort of crisis is a disaster in another.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
Its early days yet. The pitot tube theory is being driven by the ACARS data. As more data is collected different theories may develop.
http://michaelsmith.id.au
it is clear to me that the Air France crash was caused by icicles forming on the propellors, making them get stuck.
You forgot one thing. The pilot's bible states that before the pilot puts the plane into a steep nosedive they should send a co-pilot or flight attendant out on the wing to try to spin the propellers themselves to break the ice.
Nosediving should only be done as a last resort.
"Battle tested" may have been used in this context to refer to the long history of human pilots compared to the shorter history of using computers to control aircraft. If it refers to actual combat flight, flying military aircraft teaches one to expect something to break and know how to determine what is broke and what needs to be done to land safely. Military aircraft experience a lot more stresses than civilian aircraft, and thus tend to break more.
In a perfect world, the pilot would recognize a computer mis-evaluation if one occurs due to his simulator training, and over-ride the computer to land safely. In practice, this does not always occur - crashes have resulted from both non-overrides and incorrect overrides.
Although the computer may be statistically safer, if the pilot is able to over-ride obvious computer errors and is trained to recognize those errors, isn't that the best of both worlds?
I always check which type of aircraft will be used on my flight prior to committing to purchase the ticket, and do not fly Airbus. I live near an airline hub, though, so it is easy for me to decide which aircraft to avoid. If a person's local airport has limited service, that choice may not be available to them.
Generally airlines stopped hiring ex-military pilots as they tend to crash too often killing hundreds of people at a time.
Military pilots find it hard to change from "Achieve objective; fly hard and kill bad guys" to "Land passengers safely at all costs" mentality.
A huge oversimplification to say that US maker Boeing provides the freedom for pilots to fly. By the same token, you might well say that The US is the most over-regulated country on the planet, so why are pilots allowed to fly it with such freedom?
I think that in general, you are arguably better off when the pilots are connected to the flight surfaces via manual controls. Even if the power and hydraulics go out with enough strength you may move some control surfaces a little - perhaps enough to control a plane in level flight - maybe even land it.
But if FBW shits itself - you are TOAST.
And for every crash caused by pilots not being able to take the control of a plane, there's probably another crash averted by the computer.
The biggest problem of course is that flying a wide-bodied jet is 99.9999999% pure boredom followed by 0.0000000001% when you live or die because of a series of bad circumstances piling on top of each other.
If the hardware fails for any reason (pilots get wrong information) then they can't expect to live for long - especially if the computers are flying it. At least if sensors start failing, humans are flexible enough to know something is wrong, and work around it.
In general, I would prefer to be flying on a wide bodied jet that has the computer fly the entire flight, but with a pilot on board who is exceptionally good at looking at the computer non-stop to decide if it is working right. I expect that pilot to be so good, that he understands the point at which he needs to kick the auto-pilot into touch, and take control of the plane.
See my signature. It's standard, not put here for this post.
How many escape pods are there? "NONE,SIR!" You counted them? "TWICE, SIR!"
You are clueless and do not belong in a cockpit (not that I believe for a second that you actually are a pilot)
That 'whoosh' you hear is the failure of the parent poster's troll detection system. The troll detection system maintains level posting attitude for turbulent articles. CmdrTaco speculates that a similar troll sensor failure resulted in catastrophic Karma loss that may have contributed to the crash of Flight 447. Slashdot recommends that future posters be immediately retrofitted with properly functioning troll sensors.
China Airlines Flight 140 was a route from Taipei, Taiwan to Nagoya, Japan. On April 26, 1994, the Airbus A300 on the route was due to land at Nagoya Airport. The Airbus A300 was completing a routine flight and approach, however just before landing, the First Officer pressed the Take Off/Go-Around button (also known as a TOGA) which raises the throttle position to the same as take offs and go-arounds.
Pilot Wang Lo-chi and copilot Chuang Meng-jung[1] attempted to correct the situation by manually reducing the throttles and pushing the yoke downwards. The autopilot then acted against these inputs (as it is programmed to do when the TOGA button is activated), causing the plane to have a very nose-high attitude. This nose-high attitude, combined with decreasing airspeed due to insufficient thrust, resulted in an aerodynamic stall of the aircraft
-- http://en.wikipedia.org/wiki/China_Airlines_Flight_140
As an ex airline pilot and current software developer I would say that an override must be available in any system. Of course computers are much better in quick decision making and collecting all the facts than humans are. In fact with a glass cockpit, the computer knows the data before the pilot does anyway. But there is the occasion that software fucks up. Plain and simple.
From my own personal experience:
1 - Autopilot with suicide attempt
Boeing 737-400 cruising at FL310 everything happy, clear skies. I'm Pilot flying and the captain suggest I have lunch. With the tray on my lap I eat while glancing at the instruments every once in a while. The captain was supposed to have control. So after a particular tasty piece of chicken I look up only to see the horizon at an angle and way too high. I glance across and see the captain reading the news paper. Look at the instruments which indicate a gentle diving turn. The VNav path on the displays indicate nothing out of the ordinary but this Autopilot decided to go for a turn and decent anyway. The whole thing would have only lasted a few seconds but there was absolutely no reason for the computer to do this manouvre. AP disconnect and reconnect sorted it all out.
2 - Lazy plane
Yeah, uh again during my mean and again I had handed control over to the captain while eating. This time at night. Cruising FL330 when auto throttle decides to close the throttles to idle. Auto pilot maintains altitude. WTF to I push the throttles back up. They stay up for a few seconds and yet again move to idle. Got rid of my food and disconnected the auto throttle. Set cruising power manually and checked everything. Nothing wrong. Re-engaged the auto throttle and things were fine.
3 - Dutch roll gone bad
Climbing through 10.000 feet on auto pilot, the plane begins a slight rocking left and right. No more than a few degrees. As we continue to climb the rocking gets worse. 5 deg bank either way. Auto pilot is working hard to compensate or so it seems because the control column moves noticeably. Again my luck to be pf. We thought the Autopilot had gone mad so after strapping ourselves in tightly we disconnected the ap. I tried to hand fly and stabilise but things got out of control rapidly as the plane started to buck left and right well past 10 degrees bank. I was obviously losing control. Nah, let's face it, I had no control and told the captain. He took over and at least was able to not allow it to get worse. Glad I was with this guy because he flicked off the yaw damper that is an automatic control system to stop an aerodynamic effect called Dutch roll. The plane steadied immediately although we were left with the Dutch roll effect but that was not too bad.
So there you go. In all three cases it was not a matter of pilots being better than computers. Overrides are required when the computer goes mad. I always valued having the mechanical controls as a backup in the 737. I travelled in Airbus aircraft and I no longer fly but I would still hesitate to be a servant to a fly by wire system.
what people are forgetting is that the airbus plane DID return nearly full control to the pilot (nearly because there are still limits to things like how much roll one can request, but these COULD be built in mechanically in the absence of fly-by-wire).
The real issue here is that the computer system detected invalid input and handed the control back to the pilots (under "alternate law" which means most safety rules are disabled), but the pilots may not have had enough information to know whether the control was handed back to them in a safe state, and if not, how to correct.
On top of that, the airplane was flying fairly close to the coffin corner (where the airplane is capable of going too fast and too slow simultaneously, and at this point, in this situation, computers are really helpful). One possible issue is that a gust of wind could have caused "mach tucks" if they were going a little too fast (thus causing downward pressure on the nose during gusts). These could have placed significant stress on the airframe until things started to fail. I have some other theories and observations about debris and ACARS messages, but this isn't the time for that now. All I will say is that all indications are the airplane was flying too fast, and there is NO indication that the instructions Airbus has sent to pilots will remedy that problem because it is unlikely that the pilots would have had sufficient information to act on them.
There are two issues involved here that need additional discussion though:
1) Are airplanes built to withstand forces as well as they used to be? Would, say, a DC8 be able to withstand more turbulance than an A330?
2) Do FBW systems provide sufficient feedback for a pilot to feel the plane? Could accidents be avoided in cases like this by adding additional feedback?
LedgerSMB: Open source Accounting/ERP
It was a "battle hardened" human who flew the 'plane into the middle of a massive thundercloud in the first place.
No sig today...
As long as L. Ron Hubbard wrote the avionics software, I'm *so* boarding that plane!
you had me at #!
Speaking as a European it is not an irresponsible headline because, if you read the whole summary it does present a balanced case: human ingenuity vs. computer speed and multi-tasking. For example there was a mid-air collision (over Brazil?) several years ago caused by a human air traffic controller overriding the automatic collision avoidance instructions so human ingenuity is not always helpful! The fact that you got upset by this suggests that you think human ingenuity is always the best choice and you are unhappy that Airbus chose not to rely on it - which is your prejudice not the author's.
However the snippet is wrong in that it is extremely surprising given the comparison between US and European cars where the situation is completely reversed. Drive a US car and the damn thing won't let you start the engine without a manual having to have BOTH the clutch depressed AND be in neutral which is plain stupid since either is sufficient and I usually just depressed the clutch to start the engine. Not to mention the number of times the stupid thing pings at you: put your keys in the ignition without turning on the engine *PING, PING, PING*, turn off the engine but down't take your keys out fast enough *PING, PING, PING*, put some luggage on the passenger seat *PING, PING, PING* (no seatbelt!), driver not yet irritated enough *PING, PING, PING*. Of course it also pings at you if you leave your lights on, which is useful, but by this time most people have reached under the dashboard and forcibly removed the device which goes *PING* in order to retain their sanity. This makes it about as useful as those stupid dialogue boxes that ask you "Are you sure you want to do that?".
So given this experience I am extremely surprised that it is the opposite way around with aeroplanes.
Crossing the street and driving a car are both 'decided risks" too. It's just that infrequent but large scale fatalities generate more paranoia and subsequently bigger headlines than daily individual fatalities.
it's all electronic control, rather than hydraulic/ pneumatic controls. meaning its more simple, but it's also more rigid: if your computer goes, so goes your aircraft. yeah, they use triple redundant systems, but how many electric surges do you need to take out 3 computer systems in an aluminum tube?
learned from this interesting comment:
http://community.nytimes.com/article/comments/2009/06/02/world/europe/02plane.html?s=3
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
Too bad the trolling/ignorant summary runined this discussion. However it's based partly on fact. It's common knowledge among pilots that Boeing planes generally cater to pilot's wishes for control more than Airbus, but that has more to do with company attitudes rather than country. From this article on the crash of US Airways 1549 (an Airbus 320) and the history behind Airbus: a charismatic French test and fighter pilot named Bernard Ziegler, now retired, who must stand as one of the great engineers of our time. He was (and is) despised within the French airline-pilots' union, because he openly discussed designing an airplane so easy to fly and crash-resistant that it would be nearly pilot-proof. He did not say "idiot-proof," but his attitude was undiplomatic in a country where pilots still wear their uniforms proudly, and it was also unwise, because, as the record has repeatedly shown, if you emphasize to pilots that they are flying a safe design, they will go to great lengths to prove you wrong. In any case, Ziegler had to live under police protection because emotions grew so strong. So clearly, the French take the idea of pilot control just as seriously as Americans do, but Airbus opted to go a different route. I have no idea what the other American and French companies (some now defunct) like Lockheed, Aerospatiale, etc are like.
i read somewhere about a pilot flying an empty cargo plane (large-size jet, iirc) back who put it through a vertical loop (vomit-comet style) just for fun. seriously annoyed the company, as it knocked a few thousand hours off the lifespan of the plane.
Pilots in the airforce do this kind of stuff all the time. My colonel once had a fighter try to steal his landing approach when he was flying an empty cargo plane. Empty those things have tons of lift, so he threw the plane on its side and outturned the fighter to make the landing.
And like those scenes in Top Gun:
When my dad was in Thailand during the Vietnam War, they got a new general in at Kurat AFB, and marshalled the whole base for this formal ceremony. Right in the middle of it, an F-4 pilot buzzed the crowd at a very low altitude (the general on the stage hit the deck). Nobody could figure out who did it ("oh, sorry sir, all the planes were in the hangar that day"), so the guy was never caught. But then again, they didn't try very hard either, since that's the culture in the Air Force.
Especially which limitation you would like to override? It's unclear that if the accident was due to the inability that pilot's unable to override tho computers' limit.
How about this? http://en.wikipedia.org/wiki/China_Airlines_Flight_006. A Boeing flight, which pilot's manoeuver resulted in a 5G load and barely destroy the horizontal stabilizers. With less luck, it the CA006 might lost the whole stabilizers and could result in JA123 - http://en.wikipedia.org/wiki/Japan_Airlines_Flight_123.
May be without the 5G manoeuver the plane will be lost, but I doubt if it was an Airbus, could the plane becomes >66 deg bank in the first place (due to the protection of another computer limitation), and hence such 5G manoeuver would not needed.
From the article,
But I prefer pilots to sharpen and practice the emergency handling skills with simulator...not the real thing.
Flying manually without autopilot in the turbulence is like driving at 100mph on icy road without electronic traction control. I still think computer is in a better role in handling that.
And the article author and the summary are both full of it.
Perhaps not the most diplomatic response, but it is true enough.
First, there is absolutely nothing conclusive to say about Air France 447 at this point other than it did indeed crash (thus ruling out alien abduction and time travel). There are no conclusions, or even anything that could really be called a theory, just guesses and hunches ranging from informed to wild-arsed. At this point, nobody can even be certain as to whether the mismatches in indicated airspeed happened before or after the aircraft started to break up. As WAG level example, if lightning had damaged the radome at the nose of the aircraft (has been known to happen), then the three pitot probes could report different velocities not because the probes failed, but rather because to aircraft no longer conforms to the aerodynamic profile the pitot probes are calibrated for.
Also, the difference between Boeing and Airbus is not as stark as the author would like to think. On both manufacturers' most recent aircraft, in normal flight the computers will automatically do a variety of nifty things (like auto-mixing the use aileron/rudder inputs, vertical gust load alleviation, etc, to increase efficiency and comfort) in ways entirely transparent to the crew. The differences are at the extreme limits of the flight control laws. There, if the pilots pull on the controls hard enough, a Boeing plane should accept the input even when the computer thinks the input will cause permanent, or even fatal, damage to the aircraft (it will warn the crew, loudly). An Airbus plane will limit the input so as to avoid such damage (and notify the crew it is doing so). There are legitimate arguments for both configurations, and America vs Europe has nothing to do with it (old dog vs new pup might, if you could go so far as to call Airbus a new pup). At the extreme limits it is not a matter of ingenuity versus information, but more of protecting what you have left right now (an unbroken airplane in danger of crashing), or allowing risks that might let you get to a better place (a damaged, but perhaps un-crashed (for now) airplane).
In either case, by the time a flight crew encounters the philosophical differences between Boeing's and Airbus' respective control laws, they are already frakked, and in a damned if you do, damned if you don't scenario.
In both cases, part of the flight computers programming is there to monitor itself, and its sensors, for failures that would compromise its function. In a situation where the airspeed indicators no longer agree with each other, the computer should automatically reduce any limiting role it has because the computers' input data is no longer reliable. And as current commercial airliners are reasonably stable in the aerodynamic sense, they can continue to fly even in the event of a total computer failure. Look carefully at cockpit pictures of the shiny new Airbus A380 and you will see a small cluster of old fashioned instruments amongst all the flat panel displays. The computer can fail, and of all the things on an airliner, the computer is the item most aware of this.
> It's essentially a question of what do you trust most: a human being's ingenuity or a computer's infinitely faster access and reaction to information.
No, it's who do you trust most: a human pilot's ingenuity in reacting to a novel situation or a human programmer's foresight in accounting for every possible situation.
- For the complete works of Shakespeare: cat
the simple fact is we think this particular French Airbus crashed do to design failure, specificity computer related and not human failure and this only strengthens the case for humans to still be able to fully operate complex machines.
The autopilot disengaged at 23:10, 4 minutes before the last automated messages indicating failing cabin pressure were sent by the plane.
provide us with 2 examples where the pilot decided to manually override the flight computer and crashed.
Here is 1: http://en.wikipedia.org/wiki/Bashkirian_Airlines_Flight_2937.
Basically, the on-board computers gave the correct advice, but one of the pilots "disregarded the TCAS instruction to climb and instead began to descend, as instructed by the [air traffic] controller, thus both planes were now descending."
The controller was later assassinated by someone who had lost wife and children in the accident.
So.... are we saying that a human pilot should be allowed to fly a plane in a 25 knot window?
I hope not.
No sig today...
You're remembering the popular media speculation of the time, now turned into myth, which, as is often the case, was completely misinformed. See links posted by myself and others above in this sub-thread.
I use Friend/Foe + mod-point modifiers as a karma/reputation system.
From where I'm sitting, it seems boeings fall out the sky with more often and with more devastating results than Airbuses - http://news.bbc.co.uk/2/hi/in_depth/2008892.stm
I particularly liked when the A320 came down in the Hudson how, it was "all thanks to the pilot"...and yes, in part it was, but the minute another airbus falls out the sky and it's fatal this time (as crashes often are) it's clearly because of poor design philosophy?
Meh, this whole thing stinks of US vs EU chest-bashing.
throw new NoSignatureException();
This is not correct. The engines naturally take a finite time to spool up from low power to climb - about nine seconds. What the computer refused to do was allow the pilot to pull the nose up into what would, at the low speed the plane was at, have been a stalling attitude. It is arguable that, had it allowed it, the plane just might have been able to "bunny hop" the trees and recover as the engines spooled up. More likely, it would have lurched up, stalled, and crashed more violently than it actually did.
This was a classic case of computer-induced overconfidence. The pilot assumed that the computer would not let him make a mistake, and set the controls for to fly as slowly as the computers would let it. Which gave it no spare energy to climb out of trouble. But the computer could not "see" the trees at the end of the runway. As one commentator put it, the pilot flew the plane into a hole in the ground, trusting vainly in the computer to get him out of the impossible state he put the plane into.
Consciousness is an illusion caused by an excess of self consciousness.
CFM International is working on a software modification for its CFM56-5B engines after a series of engine stalls on Airbus aircraft in 2008.
Evendale-based CFM is a joint venture of GE Aviation and France's Snecma. The high-pressure compressors and combustors for CFM56 engines are produced by GE, and the engines are assembled in Evendale and France.
The Airbus A320 can be powered by either two CFM56-5 engines or two IAE V2500 engines. Regardless of the engines, the plane has the same operating specifications, and the casual passenger notices no difference.
Fiat ???
In 1982, attention was focused on developing an engine in the 25,000 lbf (111 kN) thrust class for the 150 seater market. The engine was initially called the RJ500-35, but when Pratt & Whitney, MTU and FIAT joined the consortium some time afterwards the engine was renamed the V2500. V denotes the five original partners, whilst 2500 symbolizes the original thrust level of 25,000 lbf (111 kN). FIAT later withdrew from the consortium.
Troll.
More accurately, there are very few people on Slashdot who have any fracking clue how a fly-by-wire system works. It's evident from the comments; just like everything else, people go spouting off and making claims about what they think things are like based on just a tiny bit of knowledge and their own prejudices, rather than looking at the facts and finding out what things actually are.
(Full disclosure: My day job is developing and testing a new FBW system, and I took an entire course dedicated to this in college.)
FBW systems are not the autopilot. They are not autonomous AIs, they do not make their own decisions, they do not just arbitrarily "decide" to go do something against the pilots' wishes. FBW systems are, in essence, little more than simple feedback control loops, similar to the familiar PDI controllers we all remember from control theory classes. All they do is compare the current state (pitch/yaw/roll angle and rate) with the one commanded through the stick, and try to make the two match by moving the control surfaces. The biggest difference is the presence of limiters which will prevent the aircraft from exceeding certain parameters (usually G load and angle of attack). That's it. That's all there is to a fly-by-wire system. It's just a controller.
In fact, let's compare a "traditional" manual system with a (simplified) FBW one from the pilot's perspective. In a traditional system, the stick/yoke in the cockpit is directly mechanically connected to the control surfaces through pushrods, bellcranks, cables, pulleys, etc. A given deflection of the stick will always result in the same deflection of the surface. For our purposes, we'll assume it's roughly linear, so Dsurface = K * Dstick. Now, let's look at the airplane as a whole. A given deflection of a control surface will not always achieve the same result--at low speeds, you need more deflection for a given response than you do at high speed. The net effect is that, at low speeds, the pilot needs to make large deflections of the stick make a given maneuver. At high speeds, he only needs to move the stick a little bit. It's kind of like your car--the steering gets more sensitive the faster you go; you wouldn't use the same inputs on the freeway as you do in a parking lot. Matching the desired response with the control input is the pilot's job--he's the feedback loop connecting control surfaces with the desired flight path.
A FBW system, on the other hand, doesn't have mechanical connections between stick and surface. Instead, the stick uses force or deflection sensors to read the pilot's input. That input is fed to the FCC, which then sends signals to the actuators on the control surfaces. Instead of commanding a given control surface deflection, the pilot's input will usually command something else, eg. roll rate or G load. Rather than varying according to speed and aircraft position, this will be constant--in other words, the command for 20 deg/sec will be the same at really low speeds as it will at high speeds. Basically, the pilot is telling the aircraft "do this", and the FCC figures out how to achieve that by moving the surfaces.
A FBW system will also often have limiters, which prevent the aircraft from exceeding certain parameters. Most common are angle-of-attack and G limiters. Angle of attack (AOA) is the relative angle of the aircraft to the oncoming air. Imagine sticking your hand out the window of your car, palm downwards. As you slowly rotate your hand so your palm faces forwards, notice that your hand wants to go up--you're making lift, and the angle of your palm to the airflow is your hand's AOA. Notice, though, that once you rotate too far, you stop generating lift--that's a stall. On a wing, the amount of lift generated is roughly linearly proportional to AOA, at least up to a point. Past that critical AOA, the air stops flowing smoothly over the top of the wing and gets all jumbled, causing a loss of lift. That's what a stall is.
The meek may inherit the earth, but the strong shall take the stars.