Boeing 737 Max Crashes 'Linked' By Satellite Track Data, FAA Says (arstechnica.com) 152
An anonymous reader quotes a report from Ars Technica: The Federal Aviation Administration issued an emergency order grounding all Boeing 737 MAX aircraft on March 13, citing new data that showed a possible link between the March 10 crash of an Ethiopian Airlines flight and the crash of a Lion Air flight off the coast of Indonesia last October. In an interview with NPR's David Greene this morning, acting FAA Director Dan Ewell said that "newly refined satellite data" from a flight telemetry system had led the agency to make the move. Both Ethiopian Airlines Flight 302 (ET302) and Lion Air Flight 610 (JT610) were recently acquired 737 MAX 8 aircraft, and both were lost with all aboard just minutes after take-off. According to the emergency order issued by the FAA, "new information from the wreckage concerning the aircraft's configuration just after takeoff that, taken together with newly refined data from satellite-based tracking of the aircraft's flight path, indicates some similarities between the ET302 JT610 accidents that warrant further investigation of the possibility of a shared cause for the two incidents that needs to be better understood and addressed."
The source of the data in question is a combination of telemetry feeds from the flights' Automatic Dependent Surveillance(ADS) system. Introduced in the US in 2001 and more widely worldwide in the wake of the crash of Malaysian Airlines flight 370 in 2014, Europe has required most aircraft to carry the UHF-band ADS-Broadcast (ADS-B) system since 2017, and the FAA has mandated ADS-B for most aircraft by 2020. While ADS-B data was initially meant to be picked up by other aircraft and ground stations, it is also tracked by satellites. Other, less-granular telemetry data sent in the subscription-based ADS-addressed/Contract (ADS-A/ADS-C) format, the Future Air Navigation System(FANS), and the Aircraft Communications Addressing and Reporting System (ACARS) are also picked up by satellite.
The source of the data in question is a combination of telemetry feeds from the flights' Automatic Dependent Surveillance(ADS) system. Introduced in the US in 2001 and more widely worldwide in the wake of the crash of Malaysian Airlines flight 370 in 2014, Europe has required most aircraft to carry the UHF-band ADS-Broadcast (ADS-B) system since 2017, and the FAA has mandated ADS-B for most aircraft by 2020. While ADS-B data was initially meant to be picked up by other aircraft and ground stations, it is also tracked by satellites. Other, less-granular telemetry data sent in the subscription-based ADS-addressed/Contract (ADS-A/ADS-C) format, the Future Air Navigation System(FANS), and the Aircraft Communications Addressing and Reporting System (ACARS) are also picked up by satellite.
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It was made in Israel so there's nothing bad you can say about it without being labelled an anti-Semite.
Indeed the flight software might not be the core cause of problem and there might be no single code update that will fix the problem. GIGO applies to software as much as it does to every system that requires data input to do work. Until the actual cause of the incident(s) are completely know we are just spouting bullshit. The rest of your comment needs to be taken for what it is, another asinine statement that deserves to be down modded.
My bet is that the software is fine and the component system design is
New data? (Score:5, Insightful)
grounding all Boeing 737 MAX aircraft on March 13, citing new data
New data my ass. The planes have been grounded because all the countries worldwide were banning them, including China and the whole EU. Grounding them from the very first moment would have been much more sensible from Boeing.
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you're saying two things.
No, the USA did NOT ground them "because everyone else was doing it."
They really did ground on the basis of telemetry
Re:New data? (Score:4, Insightful)
The US grounded them because their attempt at sweeping the issue under the rug had failed, as evidenced by many other countries grounding the planes against the FAA recommendation. So the prudent thing to do is to make up a reason why now the FAA should ground them too, as to not look completely unconcerned about the passengers' lives while being protective of Boeing's business interests.
Re:New data? (Score:4, Insightful)
Correct!
They should have all been grounded, worldwide, the instant the second plane crashed.
Re:New data? (Score:5, Interesting)
Actually it is very much sounding like they should have been grounded after incidents of the plane diving, when engaging auto pilot based upon false stall warnings. The data was all available from flight recorders, why the fuck would pilots not report it, oh that's right SHOW ME THE MONEY. Rampant corruption in the US means that two planes HAD TO CRASH prior to anything being done. They should have been grounded already, based upon several instance of this happening and pilots catching it before it was too late. A proper investigation now needs to happen to check for a greed based coverup, Boeing and the US government are in serious shit now, for the deaths of those people in those two instances where it could have been avoided.
Ford Pinto, redux (Score:1)
Rampant corruption in the US means that two planes HAD TO CRASH prior to anything being done.
Remember Ford Pinto?
Well, the Boeing 737 Max saga is a rehash of what happened back in the late 1970's.
https://users.wfu.edu/palmitar... [wfu.edu]
In both case NTSB didn't do nothing UNTIL massive backlash from the userland !!
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Chhina did that and people here said they where overreacting.
Because at the time China was the first ones and Slashdot outrage was in full swing. Reports came in from the EU grounding them only hours later. Never underestimate our capacity for pure uninformed outrage.
For example have you ever made a grammatical error in a Slashdot post?
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China was the first ones
LOL U cant even get ur singulas and plural rite!!!!!!!!! ROFL!!!!
I can't tell you how hard that was to type with autocorrect on.
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Totally agree, we were forced to do it because we'd look even dumber if we did not. I saw an interview with an ex-FAA official prior to the US grounding and they were baffled as to why we did not. Their view was if an engine fell off twice (or any hardware issue) then the plane would have been grounded after the 1st crash when they could not spot the problem. But because it was software, they gave it a pass. And they knew after the first crash that it was wonky software because the FAA gave boeing until apr
Re:New data? (Score:4, Interesting)
Pity they decided not to train the pilots on when they should do this.
They put the MCAS system in to reduce the need to retrain existing 737 pilots. They should have:
a) wrote better software, that uses both angle of attack sensors and only intervenes when both provide good data. The current software reacts to either sensor
b) Trained the pilots on how the MCAS system works, when it operates, what its full capabilities are and how it could malfunction, so they know when it needs to be disabled.
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a) wrote better software, that uses both angle of attack sensors
Please determine which sensor is right in software, remembering that the software in this case took the "safe" action of preventing what it saw was a stall.
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So basically, they installed a feature to make a new plane fly like an old one so they wouldn't have to retrain pilots. Now you're saying that pilots need training to use a feature that's supposed to obviate the need for training.
I can't help thinking it would be better to get rid of the feature and stop pretending it isn't a new plane with different flight characteristics.
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"The problem with your A is that if one of the sensors failed in a way that prevented it from detecting a stall situation, MCAS would not intervene, and the plane could crash."
That's not really the way it works. When a sensor mismatch is detected, an alarm should sound (it does for lots of OTHER multi-sensor or redundant systems) alerting the pilots that there's a problem and a safety device has been disabled. The pilots then need to make sure they fly the plane safely.
Airliners aren't supposed to stall, e
Re: New data? (Score:3)
No, the MCAS is there to prevent a stall, not to help recover from one.
The primary issue which necessitates it is that the aircraft will stall in some situations in which the original 737s would not. This isn't a bad thing inherently; every aircraft is different, which is why pilots require type-specific training. However Boeing wanted to be able to sell the MAX as the same aircraft, meaning no extra training would be required for pilots who had 737 experience. In order to do that, they had to make it pe
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Sorry, I should know by now to write *very precisely* on Slashdot. The purpose of the MCAS is to assist pilots to recover from high angle of attack situations that could lead to stalls. Actually, the purpose is to compensate for thrust characteristics that produce a net positive pitch moment, but the former sounds better.
Re: New data? (Score:2)
Yes, that's better :) I wasn't trying to be pedantic, just honestly wasn't sure if you understood the difference.
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I guess I'm not following then. The poster you replied to stated that aircraft safety systems like MCAS should disable themselves if redundant sensor data doesn't match. You noted that the absence of the safety system could cause a crash and that it's difficult to detect a fault angle of attack sensor.
It's not difficult to detect a faulty sensor when you have redundant ones and their readings don't match. In fact, Boeing has implemented precisely what the OP suggested, plus adding cross checks from other
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> fairly easy to detect AoA sensor failures....it is not.
GTFO out.. one is clearly fucked here:
https://static.seattletimes.co... [seattletimes.com]
Re: New data? (Score:2)
I am not a crook.
Comment removed (Score:5, Insightful)
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"Pile in" is not a phrase ever used regarding stock purchases. You must be new to lying about investing.
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He just used it, therefore you are wrong and a liar to boot.
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Stock will drop to a more realistic P/E, then I will pile in and pick up some bargains. BA is not going anywhere. Long BA.
Not sure what British Airways has to do with this... but if they aren't going anywhere they wont be in business long.
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grounding all Boeing 737 MAX aircraft on March 13, citing new data
New data my ass. The planes have been grounded because all the countries worldwide were banning them, including China and the whole EU. Grounding them from the very first moment would have been much more sensible from Boeing.
Countries around the globe have been banning them because there has been 2 fatal accidents within six months within the first 2 years of the aircraft's operation.
The A380 has been operating for over 11 years and not a single fatal accident. Commercial aviation is that insanely safe because most aviation safety authorities around the world take any issue incredibly seriously.
In fact only one major authority was reluctant in grounding the 737 MAX fleet and that nation just happened to be the one that bu
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Other countries: Ban the U.S. manufactured plane based on nothing but a feeling.
U.S.: Bans plane based on actual compelling link between two crashes.
I wonder who behaved more rationally and correctly here...
If the plane had been an Airbus, you would have seen equal caution from other countries in an outright ban on the model.
Of course given the FAA is pushing towards more industry self-regulation, I'm sure Boeing would be jumping at the opportunity to ground their airplanes and bring into question the safety of their products, and the inevitable drop in stock value...
Two seconds of looking at data from Flightradar 24 shows very similar profiles from both flights.
Re: Wrong Again (Score:2)
Of course given the FAA is pushing towards more industry self-regulation, I'm sure Boeing would be jumping at the opportunity to ground their airplanes and bring into question the safety of their products, and the inevitable drop in stock value...
Funny you should say that ....
"Boeing continues to have full confidence in the safety of the 737 MAX. However, after consultation with the U.S. Federal Aviation Administration (FAA), the U.S. National Transportation Safety Board (NTSB), and aviation authorities and its customers around the world, Boeing has determined -- out of an abundance of caution and in order to reassure the flying public of the aircraftâ(TM)s safety -- to recommend to the FAA the temporary suspension of operations of the entire
Re: Wrong Again (Score:2)
I'm not a stock holder yet; I'm actually waiting for it to drop some more before I buy. Want to maximize my profits. All the gloom-and-doom idiots are doing me a favour in that respect, but they're still fucking annoying.
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So there's been a crash in which the erroneous intervention of an automated system was a factor, a number of incidents in which pilot intervention saved the airframe (including one with the aircraft that crashed) and a second crash which looked like it might be related (and the evidence in that direction has only got stronger since the first grounding notifications).
I think I would ground the aircraft.
Will Boeing survive this? (Score:2, Interesting)
They have shed $30+ billions from their market cap and it's continuing to plummet. But the worst is to come: the lawsuits could do to them what it did to Pan-Am back in the day. This is shaping up to look like gross negligence on the part of Boeing.
They will be facing an unprecedented liability over this due to the choices they made for the purpose of putting profits over human lives. This thing should never have been force-fit into the 737 type rating to "save money" and doing that led directly to a mes
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Either Boeing will survive this and go to 500 dollar or it will go bankrupt. The smart money is to buy a 1 year 450 dollar call and a 1 year 300 dollar put and then watch. Either one will be profitable while the other is lost cost. NO way is it going to stay within the 300-450 range.
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There is nothing unprecedented here, unless you're a newb to aviation. Shit like this happens once in a while, and life goes on. Air France pitot tube disaster didn't bankrupt Airbus or Air France.
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Airbuses last two new aircraft programs didn't suffer worldwide fleet groundings, and they certainly didn't suffer multiple crashes...
AF447s root cause (pitot icing issues) was caused by a known issue that had already been notified to airlines with a recommendation.
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Re: Will Boeing survive this? (Score:2)
While US operators like Southwest might not (since they use Boeing exclusively) a lot of the international operators will be looking towards Boeing to recoup the costs of either sitting the planes or leasing (wet or dry) replacement aircraft. Word is right now it wont be until at least late April for the FAA to approve the MAX for flight. And that's just for the software fix and related training. If they find additional issues from the data analysis, it could be longer.
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There is no way in hell the governments of this world would allow Boeing to go bust. Far too many Boeing products out there that need ongoing support (spare parts, software fixes and all the other stuff) not to mention all the jobs that would be lost.
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True. They might have trouble selling new planes though. The 737 is their bread and butter... would you order a fleet of them for your airline when Airbus has a direct replacement that hasn't been the subject of a shitstorm?
The new 777 might get off to a slow start too, especially since it's got even more new features. The 737's problems seem to stem from sticking giant engines on a 1960s design that's major feature is how low to to the ground it is. The new 777 has folding wings.
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They will be facing an unprecedented liability over this due to the choices they made for the purpose of putting profits over human lives.
One thing you are neglecting is pressure airlines put on Boeing to make the MAX in such a way as they wouldn't have to certify pilots on a different type. There are substantial costs to airlines for such training.
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But the worst is to come: the lawsuits could do to them what it did to Pan-Am back in the day. This is shaping up to look like gross negligence on the part of Boeing.
The FAA issued an emergency AD back in November on this specific issue. Boeing contacted all customers back in November on this specific issue.
Airlines that do not comply with AD are at fault. Airlines that ignore notices from aircraft manufacturers are at fault. Airlines that defer maintenance of safety-critical systems, as happened with the Lion Air crash, are at fault.
Yes, people are going to sue the deepest pockets they can find. That doesn't mean they will win, or that they are right.
Someone posted
FAA is implicated too (Score:5, Informative)
This was published in november: https://christinenegroni.com/7... [christinenegroni.com]
By then it was already clear that Boeing had quietly added a new MCAS antistall mechanism to make the new plane somewhat act like the old plane and in this way allow pilots to switch from the old plane to the new plane without costs of retraining, and the FAA had let it pass.
Since then the MCAS documentation has been made available to the pilots but that is not enough. MCAS has been badly implemented.
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I would love to see the damn raw AoA data.
http://nefariousmotorsports.co... [nefariousmotorsports.com]
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It's the first time i see such data. Interesting. You can see how one sensor early on diverges and it keeps doing its job , only 'tilted' with 20 degrees difference. MCAS intervention is not simply based on the sensors because they don't have any exceptional values when it starts pushing down the nose.
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This was published in november: https://christinenegroni.com/7... [christinenegroni.com]
By then it was already clear that Boeing had quietly added a new MCAS antistall mechanism to make the new plane somewhat act like the old plane and in this way allow pilots to switch from the old plane to the new plane without costs of retraining, and the FAA had let it pass.
Since then the MCAS documentation has been made available to the pilots but that is not enough. MCAS has been badly implemented.
The reason Boeing had added the MCAS system is because the new CFM International LEAP 1B engines were too big to fit with the 737's frames current ground clearance. If you look at the 737 NG engines you'll notice they are oval-shaped with flat bottoms because some of the parts had to be relocated to the side in order to fit them under the wings. As the LEAP engines are even bigger, Boeing had to move them forward of the wing and raise them. This had the nasty effect of putting the thrust line directly under
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I think a real discussion could be had here is to what extent the purpose of the antistall mechanism is marketing driven (avoid retraining) and to what extent it is a fix for a serious engineering problem.
Two versions:
The relocation of the engines changed the flight behaviour. This means the pilots had to adjust to that.I assume that the pilots could do so very well, but the rules are that they have to retrain which is expensive. The purpose of the antistall mechanism is to avoid the retraining.
Or: the flig
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This had the nasty effect of putting the thrust line directly under the wing, changing the handling characteristics of the aircraft, particularly making it possible for the engines to increase the angle of attack.
Oh my, this is unconscionable.
Oh wait. Every aircraft I have ever flown has an engine in a place where changing thrust will either cause a pitch up or down. It depends on where the center of thrust is compared to the center of mass. And learning how and why it happens is part of learning how to fly.
The engines need to be moved back under the wing so that the thrust line is not going under the wing any more.
Ummm, moving the engines "back under the wing" certainly is going to have the "thrust line" going under the wing. Please explain why you think an engine under a wing isn't producing thrust centered under the wi
737 Max is a frankenstein's monster (Score:4, Informative)
It has fuselage from the 737, Engines from the 787, flight controls from the A320 (the famous plane where the automation led to crashes. Now 737 Max has taken that mantle)
Boeing should have done a clean sheet design as a replacement of 737 instead of putting engines so big on an airframe meant for much smaller engine.
They created and unstable plane and tried to fix it in software.
While this is an approach often used in fighter jets which are deliberately made unstable so that they can change directions easily its not something you do on a civilian airplane. A civilian pilot does not have the reflexes of a fighter pilot to fix things if the computer is misbehaving
To recap the plane was too small for the engines they wanted to put on it. So they put the engines in a cantilevered position so now the center of thrust was significantly away from the centre of gravity and the plane had a tendency to pitch up and stall. To avoid this they added MCAS which would pitch the nose down in case of a stall detection. To detect the stall they used the AoA sensor and in a freshman Fault Tolerant Computing bug depended on only one sensor when they had 2. They made the warning light showing the AoA sensor is broken an option (only American signed up for this option which is probably why American hasnt had a crash). Then to make things worse they didnt tell the pilots. Also in the NG if the auto trim was runaway pulling back on the yoke would disengage the auto trim. With MCAS they changed this. The auto trim would only disengage for 10 seconds and then MCAS would add more trim and it would keep adding more and more trim till the pilots could not counter even if they pulled the yoke all the way back. Again a software bug. Further to make things worse THEY DID NOT TELL THE PILOTS ABOUT THIS CHANGE. So the yoke maneouver does not work so the only maneovour that works is disengaing the trim using the 2 cutoff switches but this only disengages the Auto trim. If the plane is already nose down it doesnt go back to normal trim. Now you have to pull back on the yoke which was not working till a moment ago or spin two manual trim wheels to get the trim back. All this is happening close to ground as MCAS only engages at low speeds found at takeoff.
Boeing could have avoided this in many ways
1) Build a clean sheet design which is stable with the larger engines
2) Failing that build a MCAS which is fault tolerant with multiple sensors or can be countermanded by the pilot by pulling back on the yoke (This is what they are doing now with the software fix). Not ideal for if the pilot is really flying badly now he can stall the plane
3) Failing that tell the pilots about the MCAS system, the change in the yoke behaviour and have them go through difference training.
They did not do 1 as it would cost too much money
They did not do 3 as they wanted to avoid airlines having to train pilots making the plane easier to sell. One of the reasons there are 5000 737 Max orders is that it needs no crosstraining to fly (officially)
They did not do 2 because of sheer laziness or stupidity in the engineering team
So the Engineering team is now fixing their error No 2. But the Exec team's error No 1 and the Marketing team's error no 3 are still not fixed.
Re:737 Max is a frankenstein's monster (Score:4, Insightful)
Unfortunately they were a victim of market forces in deciding to re-engine. They had to make a response to Airbus, and a clean sheet airplane would have pushed their biggest client to Airbus due to fuel costs, as it would take about 3 year longer.
That said, the solution is miserable and should not have been certifiable based on what we are hearing now. For Boeing’s sake, I hope they didn’t realize just how bad it was before the first unit was handed over.
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American did force their hand but Boeing is not a small company. They have a pretty much unlimited amount of cash from Defense contracts. If any company is in a position to do the right thing its Boeing.
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American didn't actually force Boeings hand, because when they split their order between Airbus and Boeing, they ordered the A320NEO and "whatever aircraft Boeing come up with as a 737NG replacement". It was pretty unprecedented.
At that time, Boeing still had the narrow body replacement under study - they could easily have continued with a clean sheet.
So no, it wasn't American that forced Boeings hand.
It was, however, the thousands of other orders Airbus were picking up from 737 customers...
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It does not use engines from the 787. It uses these: https://en.wikipedia.org/wiki/CFM_International_LEAP
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If you read the article you linked to you would see that the CFM Leap is a scaled down version of the GenX used on the 787.
Re:737 Max is a frankenstein's monster (Score:5, Informative)
flight controls from the A320 (the famous plane where the automation led to crashes.
Which famous crashes? I only quickly browsed through the List on Wikipedia [wikipedia.org] and the only one that stood out was Lufthansa Flight 1829, that due to TWO faults AoA sensors (unlike 737-MAX's 1 faulty AoA sensor), commanded a nose down stall recovery. Pilots disconnected the system and recovered.
There is Air France 447, on an Airbus A330. There was a sensor malfunction which led to a sensor discrepancy. The plane detected this, deactivated Auto pilot, and switched to Alternate law. Allowing the pilot to operate outside the protected operating envelope that people blame fly by wire on. They pulled the nose up, the plane responded to the command, told them they were going to enter a stall, then let them enter a stall, and the plane continued to respond to their command for nose up elevator, with 100% thrust, in a stall, all the way from 38,000 ft to the ground. You also had poor crew management where they were both trying to fly the plane with opposing commands on the controls. How should the plane know how to react to such poor crew resource management?
You do also have the A320 that successfully ditched on the Hudson. One of the only cases of a commercial jet successfully ditching.
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I think he was probably referring to the Air France A330. Unfortunately for his point, the problem there was genuine pilot error after the software did the right thing.
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Air France 296 [wikipedia.org]? A320s may be good at topiary, but you can only use them once.
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You mean when they were foolishly doing stunts in an A320 at low altitude?
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There is Air France 447, on an Airbus A330. There was a sensor malfunction which led to a sensor discrepancy. The plane detected this, deactivated Auto pilot, and switched to Alternate law. Allowing the pilot to operate outside the protected operating envelope that people blame fly by wire on. They pulled the nose up, the plane responded to the command, told them they were going to enter a stall, then let them enter a stall, and the plane continued to respond to their command for nose up elevator, with 100% thrust, in a stall, all the way from 38,000 ft to the ground. You also had poor crew management where they were both trying to fly the plane with opposing commands on the controls. How should the plane know how to react to such poor crew resource management?
Some of your details are right in that the plane detecting all 3 speed sensors failing switched off Autopilot; however, the design of the Airbus 330 did contribute to the crash. For example the throttle position was at 100% but it was at 80-85% thrust. This is one of problems of some of the Airbus controls in that they are electronic and don't reflect actual physical position. When the pilots put the plane into autopilot they set the thrust and pitch electronically but the throttle stick itself doesn't move
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The smoking gun for this incident isn't going to be what the final report says. It'll be on some notes by some engineer when this project started saying everything above. There isn't a way that this project made it this far without some intelligent engineers speaking up and getting over ruled by management.
I lasted exactly 45 days in Aerospace. It was terrifying, they picked a "COTS" architecture that hasn't been "COTS" since the Macintosh moved away from 68k. I was told to 'deal with it'. Other people quip
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A civilian pilot does not have the reflexes of a fighter pilot to fix things if the computer is misbehaving ...
Actually they have.
However the plane is super heavy and has lots of inertia, the engines are relatively weak. And a plane that size reacts slowly to the stick
Re: 737 Max is a frankenstein's monster (Score:4, Insightful)
I'm amazed that someone so full of shit can write such a long comment. Others have already addressed some of your nonsense, so I'll focus on this bit:
Failing that build a MCAS which is fault tolerant with multiple sensors or can be countermanded by the pilot by pulling back on the yoke (This is what they are doing now with the software fix).
That's just a lie which demonstrates that you don't even understand the systems being discussed. If pulling back on the yoke resulted in disengaging MCAS, then they system would literally never operate. That wouldn't be a software update so much as a permanent off switch.
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So they had 3 seperate chances to take the right path.
1. Design the airplane right
2. Design the workaround right
3. Train the pilots right
They chose the wrong path 3 times, taking shortcuts instead. Why?
The only common reason I can think of: Greed.
Saving dollars on manpower, sensors.. making the model appeal more to customers, shortening time-to-market, taking business away from competitors.
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and in a freshman Fault Tolerant Computing bug depended on only one sensor when they had 2.
Thought experiment for you:
How do you determine which sensor is correct?
What is the safe reaction to the sensor value?
Let's see how "freshmen" you can get.
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You have 3 sensors and vote. If all 3 are showing different values you take the middle value or if you rally want to be safe dont fly.
If you are too cheap to have 3 than you at least check both are agreeing, if they ar not agreeing you dont trigger MCAS instead show a warning that the AoA is not working as at least one is incorrect if not both and again if this is before takeoff you dont takeoff.
The American Airlines planes actually have this indicator but Boeing made this an optional feature and both plane
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You have 3 sensors and vote.
You don't have 3 sensors available, you've changed the design of the plane. But since you're advanced enough to acknowledge that 2 sensors aren't suitable you're a damn sight better than most of the Slashdot armchair wannabie engineers, so I tip my hat to you already since this would be the only solution that really makes sense.
But let's continue. You've just designated the "safe" state to disable a fundamental stability system on the plane, one which makes the plane respond differently to the pilot. This
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Planes fly with broken instruments all the time. The manufacturer provides lists of what is critical and what can be worked around through override procedures. AoA sensors were not on the critical list earlier as MCAS did not exist. Evidently it was not moved to the critical list even though now with MCAS a AoA malfunction can cause a crash.
Also the AoA diagree warning light was made an option. It really should have been mandatory with MCAS being on the plane.
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"It has fuselage from the 737, Engines from the 787, flight controls from the A320"
The 787 can use two kinds engines, from two different manufacturers, which are 40% larger than the engines for the 737 MAX8 which are from a third manufacturer. The A320 is from a completely different manufacturer and most definitely doesn't not share avionics.
Out of three factual statements made here, only one is correct. I would suggest this does not bode well for the "informative" moderation of the rest of the post
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The 787 can use GenX from GE Aviation. The Leap engine is from a joint venture of GE Aviation and Safran which uses a scaled down core from the GenX engine.
The A320 was infamous for not trusting pilots and having the computer override them. At that time Boeing went on to advertize that in Boeing planes the pilots are always in control. Basically Airbus has had this kid of system for long time and initially they too had crashes as pilots got used to being not in final control.
This is the first time Boeing ha
There is a word for this. (Score:2)
Overcomplexifabulocation.
Aerospace "Mission critical" software is made very different than consumer software. It is done this way to avoid potential fails from the likes of function calls, goto's, procedures calls, etc. by not using such methods and by using development tools that automates a lot of code creation. There is well defined mathematics involved in the coding.
With this in mind it'll be interesting to see where the software fail happened. I wouldn't be surprised if competing software development t
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While your comments are sound, "where the software fail happened" may not be correct apropos of your premise about technically robust coding practices. The problem could just be bad design and logic. The software could be perfect in that there are no errant procedure calls, no faulty branch logic, no page faults, no divide by zeros, no stack overwrites, etc. But, imagine we lived in a community where, by law, vehicles are only permitted to make right turns (to make a left, make three rights). So, to se
MAX really needs more pilot training (Score:2)
The Pratt And Whitney engines used by AeroBus, PW1000, have very low fuel efficiency compared to other engines of the same size, they could be swapped in for older engines onto new AeroBus airplanes very easily. Boeing was trying to compete with these but had to use larger engines that did not benefit from the same technology (patents?). It used software, however, to make the MAX airplane fly like a 737, even though its not really a 737. Because airlines do not want to retrain pilots, it glossed over the di
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As I read American chose to have the warning light which tells them that the AoA sensors are disagreeing. Didnt know Southwest had chosen to have the same warning lights.
If thats the case and American and Southwest have procedures in place that the AoA sensor is on the critical list and planes dont take off if they are broken than FAA was probably justified in not grounding planes in the US.
United flies the Max 9 which has not had crashes and as its a stretch it probably has differnt aerodynamics and doesnt
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The PW1100G and CFM LEAP are pretty similar in size. The A320 can use either. The LEAP 1B from the 737 MAX is actually smaller than the LEAP 1A used on the A320 NEO.
The problem is that the 737 was designed to sit very low to the ground. It makes loading and unloading baggage a lot easier, and is a major selling point. On the original 737 it wasn't a big deal because the low bypass turbofans of the era were small diameter. Newer planes had to use high bypass turbofans, and actually needed specially designe
I'm amazed (Score:1)
Re:Sorry Kendall, C6gummer, you're grounded. (Score:5, Insightful)
You're a bit early to be running off at the mouth about that AC, until investigations start making reports
Re: (Score:2, Troll)
Re: (Score:2)
You missed "Eyewitness report notoriously unreliable"
Re: Sorry Kendall, C6gummer, you're grounded. (Score:1)
Learn how moderation works and ac posts won't be a problem.
Granted it'd be even better if Slashdot wasn't run out of the back of someone's cigarette-stained efficiency and had the money to update - god help me - the ol' hosts.deny file. It's 2019; the shitters here are hardly intelligent enough to route around simple IP blocks. Half the contributing users aren't, after all.
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Americans can be *very* loyal to Boeing. Kind of like the few people who still insist GM or Ford are the greatest, even though Japanese manufacturers make far better vehicles. ;)
Now if you want to get Canadians riled up, say something bad about Bombardier... no most of us hate them too.