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World's Largest Passenger Plane May Be Unsafe, Some Say
CNET reports (citing this BBC video account) that some aircraft engineers in Australia are concerned about small cracks that have appeared on the wing ribs of some Airbus A380 airplanes, a report says. They're calling for the whole fleet to be grounded, but Airbus says the cracks are harmless.
Do we need to wait for a catastrophic accident where hundreds of people die?
have a tendency to become larger under stress. Airbus blowing this off is not a good sign.
Remember that story about predicted earthquake? Scientists were predicting earthquakes a lot of times, and it didn't happen. One time they were really serious about "this time" prediction. Authorities choose to ignore it. Lots of people died. Where it was? I forgot. How much "really serious" they were? Hard to say. Of course a lot more after it really happened.
So who & why would want to cover anotherwho's ass on future Airbus crashes? Well that news-story is just dumb. We all know what will happen:
- Airbus crashes, we hear "we warned you".
- Airbus don't crashes, everybody forgets.
Why are we so strange behaving species? How about being more rational?
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#\ @ ? Colonize Mars
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I'm no aircraft engineer, but I do not feel comfortable with all this "pose absolutely no danger"-talk. AFAIK, particularly modern aircraft are engineered to trim down on weight as much as possible, and I would be VERY surprised if there were parts in the plane that could just safely break down posing no risk whatsoever. Such parts wouldn't be there in the first place, now would they?
Has anybody said "scarebus" yet?
No sig today...
Airbus have issued an inspection notice saying it's a materials issue, and that airlines should inspect at an aircrafts 4 year inspection interval. They would not do so, and would be overruled by the European safety body EASA, if they thought otherwise.
This has been discussed to death on aviation industry forums, and the general consensus is it's a non-issue - the calls for grounding are being headed by an industry union, not a regulatory body.
Every aircraft has cracks in it, even brand new ones - in this case, it's in a non-critical location and is non-load bearing. A check at the 4 year point is adequate for this type of discovery.
Fun fact: that is actually legal in some cases...
10 PRINT CHR$(205.5+RND(1)); : GOTO 10
This is just the unions posturing as part of their ongoing winging about Qantas doing more and more servicing of aircraft in Singapore and Malaysia. When a problem occurs in an aircraft which was actually serviced in Australia they are are strangely silent. At any other time they will winge and make loud noises to try and make it appear they are still relevant and try and somehow force all aircraft servicing to be brought back to Australia. This has been going on for years and stories on the nightly current affairs shows about it is a regular thing.
Somehow the De Havilland Comet comes to mind.....
"a few years after introduction into commercial service, Comet airframes began suffering from catastrophic metal fatigue, which in combination with cabin pressurisation cycles, caused two well-publicised accidents where the aircraft tore apart in mid-flight"
very interesting...
I can say that composites are fucking weird... the cracks may have been accounted for in the design... kinda crappy but sometimes you are designed into a corner.
I don't have a picture of the cracks so i can't really make a good determination but if its composite and on the surface its pretty much harmless and if nessesary can be fixed with local resin cure.
The ones you got to worry about...
YOU CANNOT F***ING SEE BECAUSE THEY ARE BURIED IN THE STRUCTURE THATS WHY OLD SCHOOL ENGINEERS ARE SCARED TO HELL ABOUT COMPOSITES.
Recently downgraded to: "Mostly harmless."
..says the cracks are harmless...and don't call me Shirley. /Sick I know but this that statement is a joke/
Hate to break it to you, but Boeing's planes are fly by wire too. They're just designed to act like a plane with direct hydraulic control even though they aren't.
Composites are different than aluminium. What constitutes "normal" is different than the old stuff. Perhaps people need to do some learning? I'm not a materials engineer, so I don't know - but apparently neither do the people raising the red flag.
"Every aircraft has cracks in it, even brand new ones - in this case, it's in a non-critical location and is non-load bearing."
It seems to me there must be some load stressing the components that have cracked. Whether the load is generated by aerodynamics during flight, thermal cycling from ground to very cold at altitude, or something else, it troubles me that metal is cracking when it isn't supposed to. Cracks can propagate unless they're pinned or fixed with local doublers.
What causes the cracking noted on the A380, and why is it considered insignificant?
Dear Boeing fanboy, get off your high horse.
Boeing are every bit as much Fly-By-Wire as Airbus these days, and from what I understand, that phrase is heard on Boeing cockpits as well.
uses commercial aircraft anymore?
honestly, private jets are the way to go...
the problem isn't fly by wire, the problem is that airbus computers evaluate pilot actions for correctness and override if they decide the pilot is incorrect, in situations where the compuiter judges wrong, such as when a sensor is giving faulty readings, the plane may do pleasant things like land on the face of a mountain
Snowden and Manning are heroes.
They're just designed to act like a plane with direct hydraulic control even though they aren't.
Sounds like an improvement over the feel of two non-coupled joysticks, where assuming one pilot has a clue he can not even tell what the clueless pilot is doing wrong. I'm not a big metal pilot, but I understand that in a Boeing the yokes are connected so that both pilots have coordinated movement between them; in the Airbus with a side joystick I don't even know if the pilots can see what each other are doing, and further I understand that the pilot to most recently move the stick in the Airbus takes command of the plane. If my understanding is correct, I'll take a Boeing any day.
Is it even possible to fly a large jet without fly-by-wire? Are pilots really strong enough to move the control surfaces on the wings and tail by muscle power alone? And even if they are, do they have the endurance to do it off-and-on for hours at a time?
Hi, folks - welcome aboard Manual Airlines flight 123. I'm Chuck Norris, and I'll be your pilot today; Arnold Schwarzenegger will be the co-pilot, and Sylvester Stallone will be our navigator.
...and Airbuses have a little overhead switch which puts them into direct control mode.
No sig today...
That still nonetheless uses pitot data to set the control rates - a likely cause of the Brazil kingfisher dive.
Well, it's not either/or. "Ordinary" (ok, anymore fly-by-wire is ordinary, but you know what I mean) aircraft of any size (all commercial aviation, lots of general aviation) use hydraulic actuators, not the pilot's muscle power.
Would you go in one of these.
No sig today...
Yes you can see the other pilots control stick from your position, and no, you need to do more than make an input to gain control - there is a priority switch you have to push.
The article claims "small cracks that have appeared on the wing ribs". Airbus calls it "some noncritical wing rib-skin attachments".
This sounds like the difference between a cracked bone and a sore ligament. One really is less worrisome than the other.
They are outcompeting them. And, boeing australia is boeing's largest outfit outside continental usa.
.........
https://www.google.com/search?q=boeing+australia&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a
and now, not any country in eu or eu commissions (that are MUCH more stringent than any kind of regulatory body in usa or any place else) have not found any problems with boeings, but, very Inconspicuously, australians did. the fact that boeing's largest outfit outside u.s. is residing in australia, is just a coincidence, i assure you
Read radical news here
Fly by wire is different to hydraulically actuated surfaces - hydraulically actuated surfaces are not by themselves considered fly by wire, but do add more power to the pilots inputs.
I'd wager this has a whole lot more to do with last year's grounding of the entire fleet (due to negotiations failing with unions) and the ongoing labour dispute than anything technical. As others have already mentioned, the A380 has been widely discussed in aviation-specific forums, it's likely this is a move to highlight the ongoing issues within Qantas
Is it even possible to fly a large jet without fly-by-wire? Are pilots really strong enough to move the control surfaces on the wings and tail by muscle power alone? And even if they are, do they have the endurance to do it off-and-on for hours at a time?
Pilots don't need to be strong enough to move control systems by muscles alone. Hydraulics take care of that - whether fly-by-wire or not.
pilot error as in hiding a bug in airbus autopilot or it reading faulty gauges.
http://www.thedailybeast.com/articles/2011/05/27/air-france-flight-447-crash-report-airbus-autopilot-to-blame.html
should be fine :p... nothing to worry about :p
Never antropomorphize computers, they do not like that
Of course he would. It's a Boeing, which is Made In America and therefore is PERFECT and ANOINTED BY THE BABY JESUS as the only aircraft that God himself approves of. Any defects anyone has ever reported in a Boeing are the work of the Devil and/or Mexicans.
There's a context here - the A380 heavy maintenance is not done in Australia (and so not done by their members) and Qantas and the union are currently in a massive industrial bunfight.
So any negative comments about A380 safety have to be taken in that context.
Any sufficiently advanced technology is indistinguishable from a rigged demo
--Andy Finkel (J. Klass?)
but Airbus says the cracks are harmless
Yeah sure.....
Don't be apathetic. Procrastinate!
NASA said it was perfectly safe for space shuttle to take off in freezing cold weather. Sometimes the managers don't want to look like idiots so they make up shit without knowing what an o-ring is.
That's always a tough call. Statistically flight crew error is the most likely reason for a plane crashing, but by the same token there are rare occasions where there's a sensor malfunction or obscure bug that was never uncovered by QA that causes the autopilot to be worse than useless.
Personally, I'm marginally more comfortable with Boeing's approach to it than Airbus's, but in practice it's rarely if ever been an issue.
I've seen some suggestion that if neither pilot presses the priority switch the inputs are algebraically summed. Do you know? I can not say that in all cases it would be better to have slaved yokes. I am aware of one fatal incident in a sailplane where the best guess is the passanger panicked and overpowered the pilot fighting for the stick. But I have to think it would be better to have some shared feedback between the sticks.
Actually, this is an interesting question - the answer is a resounding "yes".
What you do is have a small "elevator" on the actual elevator. So, you deflect the small "elevator" up. That hitting the airflow causes the real elevator to move down. That causes the airplane to pitch.
It like getting hydraulic controls for free, using the airflow. Doesn't work too well at the edges of the performance envelope, but used in many older aircraft.
while (sig==sig) sig=!sig;
"If it ain't Boeing I ain't going" -> So, is Gulf-stream out? Cessna? I could go on.
Airbus is typically seen as the European competitor to Boeing. They both, as per my understanding, make good planes, and tend to be comparable feature-wise. When other countries submit requests for bids for aircraft, they tend to send requests to both companies.
However, as with Boeing in the United States, Airbus suffers from some heavy politics in the EU. Each economic block cares to protect its 'precious,' and isn't above sniping the other.
And fly by wire systems are the future. The military uses them in a number of aircraft, including the F-117 and B-2 (both aircraft that the military, IMHO, hates losing). In short, the theory is sound, has been tested, with any possible problems stemming from individual implementations of said theory.
I am John Hurt.
This proves that the Airbus A380 is 100% unsafe to fly and will result in death if you board one.
Please tell all your friends - I'm hoping that I get some cheaper A380 seats when I travel later this year if we can lower demand.
Pilots don't need to be strong enough to move control systems by muscles alone. Hydraulics take care of that - whether fly-by-wire or not.
Yes but hydraulics systems have some negative aspects :
- you can't use one, you need a second one for backup and that takes weight and space.
- you have to design the airframe around the hydraulic system, its a constraint that simply doesn't exist on fly by wire airplanes which can have a more optimised airframe.
- from a reliability standpoint electric wires are better than a hydraulic system
Hydraulic system in modern airplanes is simply anachronistic. It makes no sense whatsoever.
Sadly all very large planes are inherently unsafe. The simple reason why is that it is rare to have rescue and medical personnel in numbers large enough to deal with an incident. Imagine one of these huge planes sliding off a runway during a landing and the sheer numbers of injured people that need to be rescued is beyond local capacities. We had a commercial jet go down in the Everglades just west of Miami and getting wounded people out was at least a twelve hour affair. Many died due to our inability to get to them quickly enough. The worse scene would be more than one of the huge planes striking each other even on the runways. Anybody got 1,000 ambulances for a fast response?
... someone used planes as an example of exaggerated risks to justify the use of nuclear energy.
Why the general contempt for human life and Nature?
Is money that important?
Oh... erm... well, forget it!
.
At some point we have to realize that the Internet (rightly and wrongly) gives any voice a megaphone.
So you have to decide what you want to listen to and what you want to believe.
I understand that takes more than a few neurons to rub together, but you can do it. I know you can.
Think for yourself. It's fun.
They have pissed off all the people who made these things work (or knew how they were supposed to work), and they're now hiring graduates with no idea about the technicalities of maintenance schedules etc.
A tin can with wings weighing nearly a million pounds fully loaded, sent 45,000 feet into the air . Of course it "may be unsafe".
(Actually, I'm pretty sure the maximum loaded weight is about 900,000 pounds, not a million, but for dramatic effect, I rounded up.)
You are welcome on my lawn.
pilot error as in hiding a bug in airbus autopilot or it reading faulty gauges.
http://www.thedailybeast.com/articles/2011/05/27/air-france-flight-447-crash-report-airbus-autopilot-to-blame.html
The autopilot is not bugged. The autopilot wasn't even active for over four minutes before the crash. The headline is completely misleading, as the autopilot shut down as soon as conflicting airspeed readings came in. The system recognizes that it is unsafe to have a computer flying when the computer is getting faulty data. Thankfully Airbus flight computers are pretty good about error-checking, as they detected the airspeed discrepancy and acted on it - by turning control over to the crew and telling them why.
The accident appears to have been triggered by a number of events:
- Faulty pitot tubes providing faulty airspeed indications.
- Weather radar that saw a little storm ahead, but not the big, fuck-off storm behind it until the pilots decided to fly through the small storm.
- An avalanche of data coming into the cockpit during critical moments. During an emergency, it can be difficult to avoid focusing on a few bits of data, while others slip by.
The storm was recreated in an Airbus simulator for multiple flight crews. Using data the flight computer sent back to the maintenance crews during the flight, they were able to trigger the same errors (Pitot tube failure and airspeed mismatches).
Every crew survived.
Is it even possible to fly a large jet without fly-by-wire?
747. Entered operation in 1970. Hydraulics. Analog instruments.
Except that other aircraft makers HAVE shown to do exactly what you describe. It is pretty common in fact for say Boeing to have been caught out to have tried to hide known issues that have caused deadly accidents rather then deal with the issue and save peoples lives.
When the economic incentive is big enough, human life looses all value. Look up on say Boeing doors being blown off due to known issues with the locking mechanism or indeed making the door open outward despite the obvious safety implecations vs the normal practice of opening inward.
Don't understand? Aircraft are pressured. if the door open inward the internal pressure presses it into the door frame making it near impossible to be blow out, try it yourself, kick in a door from the side it opens into, you are going to have to be pretty burly to get that done. But of course an inward opening door takes internal space you can't load cargo into that space so there is an economic incentive to have the door open outward so you can add a bit more cargo.
Boeing did it, the locking mechanism failed and people died. Multiple times and Boeing still hasn't fundementally fixed the problem by making the door open inward only. The economics of a few kilograms of extra cargo versus all the passengers on board.
MMO Quests are like orgasms:
You may solo them, I prefer them in a group.
I think you're trying to be sarcastic, but I think you're right.
Comment removed based on user account deletion
From the following very informative article, written by a very informed journalist:
http://blogs.crikey.com.au/planetalking/2012/01/06/cracks-appear-in-public-understanding-of-metal-fatigue/
"...In fact the whole regulatory process for dealing with structural cracks because of the early history of airliner design disasters, like that of the Comets, the Vickers Viscounts, the Vickers Vanguards, Lockheed turbo-prop Electras, and more recently, aged Boeing 737s and 747s, is as crushingly boring as watching grass growing. But it works."
Remember that airliner that lost its top? Couldn't happen but it did and it turned out that the reason the aircraft did not fail completly were some supports operating suddenly in a manner nobody ever expected them to but they did. In an accident there are always multiple factors working together. Maybe that support is non-critical in normal flight but what if something else breaks? Might it suddenly be the piece that determines between catastrophic failure and a harrowing incident?
A simple example exists in your car, the parking break. Pretty non-essential right? But if your main brakes fail for whatever reason, they might just be the difference between having to change your pants and donating your organs to some lucky fellow human being.
Say in your house, you have non-supporting walls. So you knock them all out. Now, is that house without the non-supporting walls as strong as the same house with those non-supporting walls? In theory it should be. So let disaster strike, both houses loose one supporting wall. Is it possible that the house with the internal walls remaining MIGHT just not collapse as readily or as fully and those unimportant non-supporting walls holding up long enough for people to have a change to get out?
A lot of people like to point out that if Airbus is caught out on this, it will be the end of them. If that was true no aircraft maker would be in business today. They all been caught lying and gambling human lives for not very large amounts of money. If you think a large company is going to fail just because they kill people you are very naive. Only in China are executives held to accounts for their actions. Read up on aircraft accidents, how they are often caused by manufacturer issues and how it never ever seems to result in any form of punishment, let alone the bankruptcy of heavily subsidezed pork industries.
MMO Quests are like orgasms:
You may solo them, I prefer them in a group.
Given the transcript, it seems to be a issue of the chair expecting one outcome and the computer doing something else:
http://www.popularmechanics.com/technology/aviation/crashes/what-really-happened-aboard-air-france-447-6611877
In particular the computer disabled all input limiters, allowing one of the pilots to hold one of the side sticks (basically a computer joystick, so no feedback to the other pilot as one find on mechanical systems) into climb.
comment first, facts later. http://chem.tufts.edu/AnswersInScience/RelativityofWrong.htm
Ok I was just on the flight that had "turbulence" in a A380 and honestly it was kind of amazing falling out of the sky...
see my commentary
https://twitter.com/johnjonesname
Comment removed based on user account deletion
If they are merely wire hangars, why are they taking stress? Surely those wires shouldn't be flopping around, or they wouldn't have bothered with wire hangars.
Whether they shouldn't be taking stress but are, or should be taking stress and aren't handling it, it needs looking into.
Infuriate left and right
A radiation therapy machine called Therac-25 had severe design flaws that caused it to kill several people. The AECL engineers and managers were overconfident and over-greedy, respectively, so even after a significant number of accidents they refused to admit that the machine was faulty.
Chances are the problem is quite serious, but Airbus' actuaries tell them that the short-run cost of performing immediate repairs is greater than the long-run cost of their insurance rates after a mechanical failure.
"If it ain't Boeing I ain't going" -> So, is Gulf-stream out? Cessna? I could go on
You could, but the small aircraft makers' numbers are much, much worse than Boeing, Lockheed, Airbus, etc.
Commercial Aviation beats General Aviation on safety by a significant margin. Even when you add in the tumor machines they make you go through on the way in....
Can you be Even More Awesome?!
A new car built by my company leaves somewhere traveling at 60 mph. The rear differential locks up. The car crashes and burns with everyone trapped inside. Now, should we initiate a recall? Take the number of vehicles in the field, A, multiply by the probable rate of failure, B, multiply by the average out-of-court settlement, C. A times B times C equals X. If X is less than the cost of a recall, we don't do one.
I think you mean duct tape: http://www.politics.php3.salon.com/2011/10/27/ryanair_duct_tape_controversy/singleton/ OK, not really.
I still cannot find the droids I am looking for...
I know its not necessary for me to remind you, since stealing and copying is as ingrained in Chinese culture as innovation is in American culture, but dont forget to steal the design updates.
the self-loathing children of 3rd gen middle class Americans guarantee this a healthy downmod. don't disappoint me, underachievers.
No, the Airbus FMSes go into alternate law when they lose speed data. In alternate law the FMS does not apply any envelope protections to control inputs - the pilots have unfettered control. This was the case in the AF447 crash. The reason for its crash appears to be that the 2nd co-pilot first stalled the aircraft at high altitude, and then continued to apply control-inputs that prevented the other pilot from recovering from the stall. AF447 was literally flown into the sea by the junior co-pilot. Sadly, because of the design of the controls, neither the more experienced co-pilot (acting as pilot-in-command in the left hand seat), and the captain (behind them, he came in once the plane was already stalled) had any idea that the junior co-pilot was applying inappropriate commands to the control stick.
Popular Mechanics had a good article recently on AF447, including detailed CVR extracts. One thing that needs to be changed though is that the Airbus average the control inputs from each stick, and does not give any feedback to either pilot that the other is applying a contradictory input. In older aircraft control yokes were mechanically linked, and it was entirely obvious to each pilot what the resulting command to the aircraft was, and what pressure was being applied. Airbus need to add this to theirs (and do Boeing do too perhaps?).
I use Friend/Foe + mod-point modifiers as a karma/reputation system.
This better not be a damned parts story!
FWIW, I read Airframe while traveling cross country and back. My co-workers at the time thought I was nuts. Hell, I'm an aerospace engineer; it would be like a surgeon reading Coma before getting some minor surgery done.
Is it just my observation, or are there way too many stupid people in the world?
FbW aircraft still use hydraulics to actuate the actual surfaces. E.g. the A380 has 2 separate, redundant hydraulic systems.
I use Friend/Foe + mod-point modifiers as a karma/reputation system.
I was going to comment about how "some people say" there's a problem isn't worthwhile listening to unless they are experts with evidence. But since it's Airbus and not Boeing (yes, I'm a Yank) I agree it's catastrophic and all flights should be grounded immediately. How dare they play with people's lives this way?
Yeah, that's what I was thinking too. Boeing just lost a huge contract in Hong Kong. Seems that landing their first "dreamliner" there wasn't enough to schmooze the Chinese, so now they're flinging crap at their aircraft of choice.
This is a great book, explains in plain English how certain things (like planes, bridges, etc..) are designed and built, and how they sometimes fail. BTW I am an engineer that teaches strengths of materials.
The factors of safety (or factors of ignorance) for aircraft are generally lower than for other structures as a concession to the weight requirements. However, they generally need to perform special destructive tests to demonstrate that the design indeed can meet the factor of safety required. Here is a good example from the Boeing 777 development:
http://www.youtube.com/watch?v=Ai2HmvAXcU0
Cracks in certain structures are expected and can be accounted for. Aircraft, being built for minimum weight, are prone to fatigue cracking in certain components. As long as you know this you can plan an inspection interval sufficient to catch cracks before they reach a critical size. Some cracks don't grow at all and are never a problem. It depends on the loading history on the part.
The gotchas are that you need to be able to inspect the part, be able to service the part, and be 100% aware of its loading environment. For 60+ years of jet travel, many of the gotchas have been caught and lessons learned.
Someone always has priority, it's not like you lose it after a period of time....
pilot error as in hiding a bug in airbus autopilot or it reading faulty gauges.
http://www.thedailybeast.com/articles/2011/05/27/air-france-flight-447-crash-report-airbus-autopilot-to-blame.html
What Really Happened Aboard Air France 447 tells the story as it stands after investigations. It's a rather chilling read. But it makes one thing clear: it was about human error. The plane was even fully operational when it crashed, as an anti-icing system had managed to bring air speed sensors back to operation before it.
Two years after the Airbus 330 plunged into the Atlantic Ocean, Air France 447's flight-data recorders finally turned up. The revelations from the pilot transcript paint a surprising picture of chaos in the cockpit, and confusion between the pilots that led to the crash.
I hate to break it to you but your wrong. -5 points you lose!
Most all of the Boeing fleet is mechanical linkage of the yoke to hydraulic proportioning vales. The 777 and on are fly by wire, but hydraulics still move the control surfaces and the proportioning vales are controlled by servo motors that are controlled by the electronic signals from the joy stick.
Hey KID! Yeah you, get the fuck off my lawn!
I still remember when Ii travelled on this monster and got in to turbulence near Malaysian waters.... OMG! That was horrible... Everything in kitchen started falling and at one time I thought, maybe it's going to crash..... But I reckon, this monster should be re-evaluated.
Funny thing...the F-16 "fly by wire" killed a number of pilots due to some wiring chaffing under load, lighting the cockpit like a christmas tree and leaving the pilot as a hapless bystander during the plunge.....on the other hand, the A-10 has hydraulic AND mechanical linkages...and some of the have come back after receiving catastrophic punishment...I'll take the fly by direct cable please.
The same concept is being reused, with flexible wings, in newer aircraft; see the modified F-18 AAW.
About 20 years ago a 747 had a minor fatigue crack on an engine pylon pin. Boeing had already had engines fall off in flight, had redesigned the pins. The solid metal pins are 2-3 inches in diameter.
This time, an international airline that I had flown on previously, dropped a 747 engine near my house! 747 engines are big, it left a shallow, burnt crater. Somewhere around the house I've got a picture. I sure hope the managers for the 380 watch this carefully, not pulling the same management economizing stunts as BP or Tepco.
The crew is trained for IAS failure. They're supposed to use a chart to manually set throttle position and nose attitude. This crew, for some reason, failed to follow the procedures.
Cha-ching, you win the internets for today. Finally a voice of reason.
A successful API design takes a mixture of software design and pedagogy.
no, no, I meant over the shelf scotch tape... you know the clear one that is about 1cm wide :)... That speed tape is way too expensive, haha
Never antropomorphize computers, they do not like that
airbus is a corporation. they only thing that they care about is what wall street and the markets think. if you think they give a damn about your safety except where it makes the the investors happy, you are a fool.
Democrats and Republicans are like AIDS and Cancer, I want neither!
Its just a flesh wound!
"Right, I’ll do you for that"
"Are You Going to Bleed on me to Win?"
"I'm invincible!"
"You're a loony!"
"All right, we'll call it a draw."
"Running away, eh? You yellow bastards! Come back here and take what's coming to ya! I'll bite your legs off!"
1) minor and noncritical
2) on a limited number
3) traced the origin
4) have already found the solution
5) have already put it in the inspection list
OK, now you can ground the whole fleet...
"Sum Ergo Cogito"
Every crew survived.
Because the only crew with a dumb ass at the stick pulling up during a high-altitude stall was the one on 447. Once the captain found out, he is heard on the black box saying "no no no".
One thing that a flight simulator can't easily re-create is an in-experienced pilot who has been flying flat with the auto-pilot on for the last few hours.
In summary:
1) Autopilot = OFF
2) Pull back on stick
3) Ignore stall warning
4) GOTO 2
You don't quite understand the situation correctly. There is multiple redundancy in the flight computers and the sensors. A single computer mis-judgement does not cause the plane to act irrationally. Sensor input readings that aren't in agreement result in an alert and they must be cross checked and the correct reading or alternate sensing device must be used. Flight control surface output signals are also compared between multiple flight control computers and again if there is a mis-reading, the system doesn't keep flying flawed, it creates an alert and goes to manual until the issue can be remedies or the still-working flight control computer put in charge.
Essentially every crash due to the manipulation of the plane in flight (not structural failure) is due to pilot error, as having sufficient simultaneous and identical failures of redundant systems to allow the flight control computers to continue to operate flawed is nearly impossible.
It's a design trade-off. Having non-coupled sticks also offers advantages in other critical situations: see for instance the Air India IX-212 incident that happened on a Boeing 737 with coupled control yokes. The pilot flying was kind of inexperienced, and somehow managed to get stuck against the control yoke while the commander was out of the cockpit, making the plane enter a dive. When the commander rushed back to his flying seat, he had to struggle and fight with the other pilot for the control of the plane, who was in total panic and kept pushing as strongly as he could against his yoke. As the commander finally managed to pull stronger on his yoke than the other pilot pushed, the flight did not end in catastrophe. But it was still quite a scary incident.
In these situations, you can see the advantages of the Airbus design, with uncoupled sticks and a priority override button. In the AF447 crash, you can see its disadvantages.
They're too big to fail!
I didn't say envelope controls, I said control rates - the gain.
Brett
World's Largest Passenger Plane May Be Unsafe, American Boeing Shareholders Say
We can still use them for transporting proponents of the patent system.
If Pandora's box is destined to be opened, *I* want to be the one to open it.
Although this you could argue it was 50/50 between a design flaw and pilot error. One pilot was pulling up (in panic?), the other was pushing down (to gain airspeed). So the system took something like the average. As you say, once the other pilot knew what the one who was pulling up was doing, he realised that they were pretty stuffed. (IIRC, he says something along the line of 'you've killed us'.)
A physical link between the two joysticks, or possibly even only allowing input from one, would have saved the aircraft.
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I'm on a A380 Flight right now - one of those with the experimental inflight WiFi (I'm sitting on the upper floor, in first class). The plane is awesome, and I feel as safe as can b ... [NO CARRIER]
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I literally have 30 minutes of booked flight time. And even I know that pilots are supposed to use positive communication about who has control of the plane. When a pilot wants to override the other pilot, he says "my aircraft" and the other pilot says "your aircraft" takes his fat fingers off the yoke/stick/trackball.
I also don't like the idea that the plane handles differently in an emergency situation.
Depends on the aircraft. A Boeing 737 for instance has hydraulically boosted controls. There are steel cables from the flight deck controls to the ailerons and elevators (the rudder is purely hydraulic), so the B737 system is sort of like "power steering". With a complete hydraulic failure, you can still muscle a Boeing 737 around (although I suspect it will take both crew members hauling back on the controls at the same time to flare for landing). Some airliners of similar size to a B737 do not have hydraulic controls at all, it's purely done with steel cables. Instead the crew are controlling servo tabs, and the servo tabs move the ailerons and elevators.
Larger aircraft like a DC-10, MD-11, Boeing 747 are pure hydraulic. If the hydraulic system fails, you have no control over the flight controls. The only control you do have is differential engine thrust. This has happened a small number of occasions (look up Sioux City DC10 crash).
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1) the less experienced pilot was left on the stick while 1 pilot stayed there and the most experienced left for a pause.
2) once the indicator showed the wrong speed, the less experienced pilot started to climb up and regain altitude
3) this triggered stall warning to which the less experienced pilote answered by pulling the stick instead of pushing. THAT alone was the first terrible error. Most category of stall except rare one impossible with big airliner have you PUSH the stick to gain speed.
5) the other pilot tried small course correction unaware the less experienced on was still pulling the stick.
6) the "middle experienced" pilot to the less experienced one to leave the stick to him, but he apparently did not
7) when the most experienced came back in the cabine a few dozens of second before the crash it was already too late.
The whole story scream of pilot error on the side of the less experienced one. Sure the pitot failed, but pulling a stick to a stall warning ? No way.
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And exactly the same situation in AF447, the 2nd office / right-seat co-pilot (and pilot-flying initially) kept pulling on the stick. At least with coupled yokes, such as in IX-212, that this is occurring is clear to the other pilot who can then take some physical action. On AF447, because on Airbus there is no cross-stick control-input feedback and because resultant command is averaged from both stick inputs, the 1st office / left-seat pilot and the captain were left completely unaware that the right-seat co-pilot - who had been ordered to relinquish control - was still pulling on the stick. They spent over two and a half minutes falling, stalled, out of the sky, with the 1st officer trying to recover the aircraft and the 2nd officer preventing this from having any chance at all by pulling on the stick. Even towards the end, ~40s before impact, when the 2nd officer let slip he'd been pulling back and was ordered repeatedly to let go of the control, he still kept pulling back (though at that point, it was almost certainly too late).
The lack of feedback is lethal.
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So you are saying these cracks are ... printed on the part? Gosh! Maybe you have a picture of a brain tattooed on your forehead.
Wire hangars or whatever, if their response to stress is cracking, they are not designed properly and they are not up to the job. I doubt a cracked part shapes the wing as well as an uncracked part. If it does, why not just manufacture them cracked and get it over with?
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The critical issue that arises from the BEA interim reports is that nobody in the cockpit was aware that they were in a stall, even if the stall alarm sounded many times and the airspeed measurements came back back rather quickly. While I totally agree that feedback from the sticks could have helped in identifying the stall condition, it remains questionable if this could have saved the aircraft.
There is a more fundamental question here: in an emergency situation such as this one, why did the crew chose to discard most of the information that was given to them by the plane ? As soon as the initial issue was identified (unreliable airspeed), it seems that almost every information provided by the plane was considered bogus and not trustworthy anymore.
The inspectors from BEA have a assembled a "human factors" panel to try to understand the reactions of the pilots. Of course, human-machine interface is probably at the centre of the problem, but the issue seems a lot deeper than just stick feedback.
http://www.supercub.org/forum/showthread.php?41793-Air-France-447
About a third of the way down the thread is a comment by Dick Rutan.
Having recently flown on 4 Singapore Airlines Airbus A380 flights (to and from Australia), I noticed a slight resonance mode which occurred twice, one each on two of the flights. I am talking only about 700 milliseconds of resonance, like a guitar body vibrating. When it occurred, it was just as the wheels left the ground, which made me think it may have been a very slight case of fuel starvation, probably within operational specifications, that meant that thrust would flutter for a short time. This seemed to introduce a resonance from left to right, a slight left-to-right vibration, quite forceful but only lasting about 700 milliseconds. I thought at the time that this resonance, if occurring regularly enough, could help cracks develop, but considered that modern airlines have regularly safety checks which would of course mitigate any such eventuality. But now that cracks have developed, and perhaps in areas of the wing vulnerable to left-to-right vibration, this makes me wonder if this resonance could have been a factor.
But if fluttering thrust was the causative trigger, that should be very simple to work around. Apart from this slight niggle, at no time did it feel like the A380 was difficult to fly, and in particular, the first landing at Singapore was in a substantial crosswind and was handled with consumate ease, so I am very confident that it is one of the safest and easiest to fly planes in existence.
DeHavilland had similar problems - admittedly, that stemmed from the dumb decision to mount the engines in the wing roots, but still... have lessons really been learned here? Or do we have to wait until planes start dropping from the sky again!?
As I said, hydraulically actuated surfaces are not considered fly by wire, which is a whole another set of criteria and features.
I never said there were still direct connections...
The physical link would have communicated clearly to the other co-pilot what the one with the controls was doing. To me, the idea of averaging two controls is completely moronic. I really can't come up with a situation where you would want to do that. This essentially halves all inputs, drastically changing handling, and should, at a minimum, give an error when they two are at opposite ends of the extremes.
I think it is pretty easy to cluck-cluck about how the pilot responded in an emergency now, but when the plane issues a stall warning every time you push down on the stick, I think you might get the idea it is a bad idea. Pretty amazingly bad human interface if you ask me.
Sorry, one other thing, "But neither Bonin nor Roberts has ever received training in how to deal with an unreliable airspeed indicator at cruise altitude, or in flying the airplane by hand under such conditions." If you don't train a pilot, how surprising is it when they fail? Your comment is no different than if I put you in a race car on the track at speed and then said it was your fault when it hit the wall.
I literally have 30 minutes of booked flight time. And even I know that pilots are supposed to use positive communication about who has control of the plane. When a pilot wants to override the other pilot, he says "my aircraft" and the other pilot says "your aircraft" takes his fat fingers off the yoke/stick/trackball.
The popular mechanics article strangely omitted a crucial detail: The pilots did hand it over to each other a number of times since they pressed the priority buttons on their side-sticks - the computer can be heard saying "priority right" or "priority left" every time it happens. That button gives complete control to the piliot that has last pressed it.
I also don't like the idea that the plane handles differently in an emergency situation.
An Airbus doesn't handle differently in alternate law, it just no longer has the protections that it does in normal law since the computer lacks the information it needs to provide them. However, Airbus aircraft also have "direct law" and switch to it if systems degenerate even more but to date that has never happened outside simulators and test flights. In direct law there is some change in behaviour because then the controls are effectively "analog FBW" - the computer does nothing to the pilot commands but instead they move the flight surfaces directly. Not to be too picky about what you said but an aircraft is most likely to handle differently in an emergency anyway because of whatever caused the problem.
As far as AF447 is concerned, it was clear from the CVR that the first thing the pilots did was to correctly identify the situation, they can be heard saying "we've lost the speeds" and "alternate law" but that was pretty much the only thing they did right. From then on the co-pilot flying fucked it all up and the pilot not flying failed to notice it. Some people on aviation forums have suggested that when the inexperienced co-pilot panicked he forgot that the aircraft was in alternate law and therefore pulled back expecting the computer to sort everything out. It would be interesting to study in detail whether he had been in any incident in the past and then done that very thing to get out of it...
It's still pilot error if the pilots hadn't been adequately trained. The blame however, might rest elsewhere.
Totally agree that control inputs should be linked and obvious to the pilots. Is there a good reason why critical controls like yoke and throttle would be represented in a variable manner? It makes sense that something like trim control would affect the mechanical position of controls, but it is unclear what benefit there is to interpreting and possibly misrepresenting these inputs to the pilots.
It says something to me that when the captain arrived he couldn't figure out what was going on. He couldn't see the pitch, he couldn't see the rapid decent, it wasn't obvious to him that the plane was stalled, he didn't see the air speed was 60 kph. Instead the system fooled three pilots with over 20k hours into thinking that there was nothing that could be counted on.
"and do Boeing do too perhaps?"
On all commercial aircraft (and, I think, most of the military aircraft, not sure about the two-seat fighters) Boeing control yokes (not side sticks) are mechanically connected to one another, and move simultaneously for all three axes of control input. The newer jets then transcode those inputs through the flight control computer system. Fun fact: The autopilot control inputs are back-driven into the yokes. You can see the plane flying itself (although the inputs are usually subtle).
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That is a crucial detail. Thanks for adding this info about the priority button and the auditory feedback.
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the problem isn't fly by wire, the problem is that airbus computers evaluate pilot actions for correctness and override if they decide the pilot is incorrect, in situations where the compuiter judges wrong, such as when a sensor is giving faulty readings, the plane may do pleasant things like land on the face of a mountain
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