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These new planes Crashing
These new planes Crashing
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There's nothing wrong with what they're trying to achieve (computers WILL screw up less than humans), but the idea of doing it with only two sensors (and only one in use at any one time) is ludicrous. Airbus uses 3 because (assuming the pitot tubes are not frozen), it makes it easier to isolate which of the sensors is delivering the erroneous data that can thus be ignored.
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cost cutting from boeing put forward in these two articles, introducing a new feature but not telling their customers so as to avoid having to train their pilots.
https://www.nakedcapitalism.com/2018/11/boeing-crapification-lion-air-crash.html https://www.nakedcapitalism.com/2019/03/boeing-crapification-second-737-max-plane-within-five-months-crashes-just-after-takeoff.html |
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They also had a cargo plane go down last month killing 3 on board.
Looks like they'll be in deep shet for a couple of months. |
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Almost a copy paste statement from boeing after both crashes. I wonder if they used the same template after the indonesian crash too.
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I'm flying to Bristol 2mor for thurs/Fri you lot r scarin the b jesus out of me, might get the boat from Belfast instead.
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They have had many reports from aircrew about this problem apparently
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The reports that have emerged from the US are different, given that MCAS is only supposed to operate when the auto-pilot is not engaged. In those incidents, the uncommanded nose-over events were stopped by disconnecting the auto-pilot.
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Acting US Defence Secretary worked for Boing for 30 years. Hmmm?
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"MCAS is only supposed to operate when the auto-pilot is not engaged. In those incidents, the uncommanded nose-over events were stopped by disconnecting the auto-pilot."
This is mututally contradictory and isn't what I've read either way. MCAS is a souped up stall prevention system and operates under manual control as well as a workaround for the wierd thrust characteristics of their new engines being in an unusual position, which is why the Lion air crew were fighting it. |
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Cnn reporting that 5 american pilots have reported concerns over this aircraft before the recent crash
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Someone has criticised pilots have to pay their own training
And don't fully understand the procedures Crikey Stay well of these complicated planes Fly by NOTHING  |
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"MCAS is only supposed to operate when the auto-pilot is not engaged. In those incidents, the uncommanded nose-over events were stopped by disconnecting the auto-pilot." This is STILL mututally contradictory.
You've even quoted yourself, "the uncommanded nose-over events were stopped by disconnecting the auto-pilot" then went on to describe how MCAS can do uncommanded nose over events with the auto pilot disengaged.. Which is what I said.... |
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I'm struggling to grasp what you are getting at, TBH. I have said that the reports from American crews cannot be MCAS related because the nose-over events reported by THEM are occurring when the auto-pilot is engaged. We KNOW for a FACT that MCAS does not operate when the auto-pilot is engaged, thus the issues THEY have been experiencing CANNOT be due to MCAS and MUST be related to something else.
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The planes cannot crash but they did.
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I see there is confusion as to what reports you were taking about, but you can't conclude it's nothing to do with the MCAS unless you have the design in front of you. It's entire probable that it's a modular system and the decision making part of the MCAS system is also part of the model it has that describes how it should best achieve safe level flight. A system that is activated when autopilot is off as a pure safety measure but is also in effect enabled all the time when autopilot is on. In fact if you think about it, it might be surprising if it wasn't? Why would the engineers design, develop and test a system that is designed to model flight characteristics to specifically compensate for an undesirable flight due to a design that now has unbalanced engine thrust behaviour, as a safety measure, then design develop and test a SECOND system that compensates for the exact same thing as part of the more complete autopilot system? Why would they do it that way? It's not an unreasonable guess that the MCAS system is a subset of the full autopilot system, not something entirely different.
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Well, either way, what the American crews have experienced has been entirely different to what we know the JT610 crew experienced. IF you are right and it is MCAS related, we have a situation where MCAS has activated under two concurrent conditions where it should not have (auto-pilot engaged and no 'bad' AoA data received)....
The thing is a mess and needs sorting. |
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On red button today
Boeing have grounded all 737 max aircraft Might as well, I should not think they were selling many tickets for them Air passengers like to feel they have a chance of arriving at their destination alive  |
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Although punters who like to lay 1:01's on here, may have taken the chance
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Air France 447 was lost in 2008 in possibly similar circumstances (computor error)
AF447 crashed due to pilot error. The co-pilot pulled back on the stick sending the plane into a stall. The captain only realised what was happening when all too late. |
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They say the new training was a hour long Ipad video
Christ LIKE A VIDEO GAME  |
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Black Box data should be available this weekend.
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That's the boeing/FAAs fault. If the model changes enough you need more training so they wanted to treat the plane as "like for like". So they tried to hide the flight characteristic differences in software, then hid the software changes from the manual, and said "it's just another 737", when it's actually "a 737 that can start trying to pretend all by itself it's a depressed japanese Zero pilot that's just sighted a US aircraft carrier in 1944". Given how insanely litigious the US is, surely there must be a good chance of a lawsuit (e.g. Lion victim families) coming down the line?
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WALL STREET JOURNAL
A grand jury subpoena seeks broad documents related to the jet liner https://edition.cnn.com/2019/03/17/politics/transportation-department-faa-boeing-investigation/index.html |
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I'm tempted to bookmark this fred for when the first "software issue in driverless cars" leads to a chain of fatalities..
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the seattle times has a whole series of interesting but deeply concerning articles on this.
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seems they were approving their own safety approvals
https://www.seattletimes.com/business/probe-of-faas-oversight-of-boeing-737-began-before-second-crash/ |
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It's hard to certify software in any meaningful way anyway? It's not like an I beam in the wing or something. If it's 1000000s of lines of code they aren't going to read it all and it only needs one line to be wrong to cause a bug. This line here in that article is scary if I'm understanding it correctly: "The newspaper said the analysis also failed to account for how the system could reset itself each time a pilot responded — in essence, gradually ratcheting the horizontal stabilizer into a dive position." I thought when I heard reset mentioned (perhaps above) it was a reset to either a disabled state or an initial no trim state, not to the current state which then might be modified again in a bad way. IF that's the case to how I now understand it, that's horrific.
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Swagman the other page on that site is even better. Boeing come out of this smelling like sh1t, they deserve to be sued. I can't even believe this for example. How could they possibly design such a system that will make a plane want to nose down, and not even bother wiring it in to make it a redundant system, so it only relies on ONE sensor?
To me that's quite literally criminal. https://www.seattletimes.com/business/boeing-aerospace/failed-certification-faa-missed-safety-issues-in-the-737-max-system-implicated-in-the-lion-air-crash/ "Like all 737s, the MAX actually has two of the sensors, one on each side of the fuselage near the cockpit. But the MCAS was designed to take a reading from only one of them. Lemme said Boeing could have designed the system to compare the readings from the two vanes, which would have indicated if one of them was way off. Alternatively, the system could have been designed to check that the angle-of-attack reading was accurate while the plane was taxiing on the ground before takeoff, when the angle of attack should read zero. “They could have designed a two-channel system. Or they could have tested the value of angle of attack on the ground,” said Lemme. “I don’t know why they didn’t.”" |
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the point about there actually being two sensors really got me too. it looks like a litany of terrible decisions, i have no technical knowledge but even i could understand how poor it all was. the seattle times were asking relevant questions of boeing a couple of weeks ago, so before the latest crash and they didnt get any answers.
i have also heard an alternate view from another site, apparently there was a related problem on the lion air plane the day before the fatal crash, it was put forward that the plane should not have been flying on the day of the crash. sadly i imagine boeing will be doing all they can to blame the two airlines, lion air have a poor record so it may work a bit. however, i read that ethiopian are well regarded. boeing have already said we had all the relevant certifications ..... plenty of ex pilots, ex boeing staff and ex faa staff making their views known in those articles, some wanting not to be nameless says a lot. one article i read alleges a bit of a cover up over the kegworth crash, that was an updated 737 i think. again the complaint was that boeing said it was just an upgrade so no need for much extra training but the reality was somewhat different. |
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Redundancy is common in even SIMPLE things, a modest computer server may have redundant hard drives, power supply, other components. They even have two of these sensors on the plane and only wire this system to 1 and if it fails it can start trying to override the pilot and push the nose down? IT sounds like a wreckless attempt at cost saving.
It doesn't matter if the lion air sensor was already perhaps crap if the sensor isn't redundant and may fail at ANY time. Is it exposed to the air (I seem to remember they are). Could even a bird strike break it? One loose wire? If you've TWO you huge opportunity to see if one is wrong as it's unlikely two will fail the same way, so you can then decide which is best or just disable the system and tell the pilot. With one, you've no such option. |
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Not related to this but quite an interesting watch
. https://www.youtube.com/watch?v=IaWdEtANi-0 |
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to have two sensors sitting there already and decide to only use one to save money is scarcely believable but then i had quite a lot of head scratching moments reading those articles.
to me it sounds criminal but my cynicism tells me no criminal charges will ultimately be proven or probably even brought. |
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While there may have been a cost-saving driver at work also, the greatest motivation just seems to have been to get the MAX out there ASAP. They knew they were losing ground on the A320NEO hand over fist and did all they could (literally) to speed up the certification process, with (now) obvious corners being cut.
Interestingly, in light of the Lion Air crash, Southwest Airlines elected to upgrade to display information from BOTH AoA sensors in their new build MAXs as well as retro-fit it to their already delivered ones, and to have a 'disagree warning' displayed when bad data was being provided by one of the sensors, thus at least giving crews the chance to do something about it before MCAS has put them into a fatal dive. American Airlines had already done the same. |
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If there is the ability to override the mcas system , and I assume there must be ,
Why did the pilots not do so , that surely part of the problem And then it is a mistake to design an aircraft that is more difficult to fly than its predecessor and which needs input from computer systems to avoid disaster because of this inherent poor design which will go wrong inevitably |
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Look if you are designing something such as a passenger aircraft the fundamental flying characteristics must never have inherent faults which rely on computers to put right ,that’s bad design and very dangerous
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You can disable MCAS but in order to do so you have to correctly identify what is occurring to begin with. The correct checklist to run would be the 'trim runaway' one, but lots of 737 pilots are of the opinion that it probably would not be your first thought when presented with all manner of warnings and stick shaker messages (implying that you are too slow/at a bad attitude). There is nothing that obviously tells the crew that MCAS is operating. In fact, Boeing didn't even see fit to tell pilots that MCAS had been installed on the MAX. Even when functioning correctly, it would be normal for the 737 to be 'self-trimming'. In the true sense, what MCAS does should not be considered a 'trim runaway' as that would not stop after 10 seconds of operation.
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either the aircraft is stalling or it is not , if it is not and mcas is saying it is and pushing the nose down
switch it off |
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How do you know for sure it is not stalling if your instruments are being fed with incorrect airspeed data from a faulty sensor? You are making it far simpler a problem than it actually is when you have the thick end of naff all height to play with.
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