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SwissCanuck
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Joined: Tue Jan 14, 2014 8:06 am

Re: Updated: Final report of Lion Air JT610 has been released

Fri Oct 25, 2019 6:45 pm

Last time I got a proper flu I spiked a fever and started feeling... weird. Definitely not confident enough to pour my own glass of water let alone fly a plane.

Plenty to learn from all of this, although I'm sure we all agree the cost was far too high. The only way forward is to make changes and learn from it. Let's hope that happens.
 
BEG2IAH
Posts: 952
Joined: Thu Apr 22, 2004 3:42 pm

Re: Updated: Final report of Lion Air JT610 has been released

Fri Oct 25, 2019 7:01 pm

SwissCanuck wrote:
Last time I got a proper flu I spiked a fever and started feeling... weird. Definitely not confident enough to pour my own glass of water let alone fly a plane.

Plenty to learn from all of this, although I'm sure we all agree the cost was far too high. The only way forward is to make changes and learn from it. Let's hope that happens.


I still can't wrap my mind around how many things went wrong and then some. We can definitely say that the root cause was Boeing's bad design, but why stop there? The actual root cause is greed and an utmost devaluation of the human life. And this applies to all the parties involved, not only Boeing. May all the victims rest in peace, I really hope lessons are learned.
Flying at the cruising altitude is (mostly) boring. I wish all flights were nothing but endless take offs and landings every 10 minutes or so.
 
spacecadet
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Re: Updated: Final report of Lion Air JT610 has been released

Fri Oct 25, 2019 7:52 pm

morrisond wrote:
It's revealing after the report has been released how quiet it's gotten in here.


It's possible - though maybe a bit optimistic - that most people are taking the time to actually read it before commenting.

It's an incredibly detailed report - but after reading it you still think the pilots actions were not egregiously bad - symptomatic of a very broken training system I don't know what to say.


I'd say the pilot's actions were pretty egregiously bad. They were utterly incapable of handling any type of emergency - which is the reason they are pilots, after all. The FO, for example, did not remember his required memory items on the airspeed disagree checklist, and could not find the checklist itself - he didn't know where to look for it. The report itself notes that it's likely that he didn't know it existed. The report also notes his failure to counter the MCAS inputs with manual trim, which the captain had done, and that he did not seem to intuitively know that the increasing back pressure required on the control column meant he needed to re-trim.

These pilots would have crashed the plane whatever problem it had. The captain was marginally better in that he at least knew to counter the MCAS trim inputs, which he was doing just fine before handing the controls over. But they never worked together as a team, and the FO's individual performance was horrendous. The MCAS system shares the blame, but this plane would not have crashed in the hands of a more capable crew. It is worth noting again that the pilots of the previous flight had the same problems and landed safely - though they made some pretty egregious errors themselves, the biggest being electing to continue the flight with the stick shaker going off continuously just because the checklist didn't say to land ASAP. But they landed, because they used basic airmanship (ie. *trim*!) and followed the procedures they were trained on. It just goes to show that even *with* making some rather large mistakes, just basic piloting skills were enough to keep this plane in the air. The accident crew did not demonstrate those skills.

There is no argument about MCAS needing a redesign, and the process by which it was certified. But this crew, and especially the first officer, put in a very poor performance that ultimately doomed this flight.
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Finn350
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Re: Updated: Final report of Lion Air JT610 has been released

Fri Oct 25, 2019 8:18 pm

Another link to the report:
https://www.flightradar24.com/blog/wp-c ... Report.pdf

By quick reading, at fault where Boeing, FAA, AoA sensor repair shop in Florida, Lion Air mechanics & Lion Air pilots among others. Lion Air is the only party who has submitted a rebuttal in the final report. Quite amazing Lion Air doesn’t take their share of the responsibility for the accident.
 
kennyomg
Posts: 19
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Re: Updated: Final report of Lion Air JT610 has been released

Fri Oct 25, 2019 8:40 pm

Wait... what??

At 23:22:33 UTC, the flaps reached the fully retracted position and the automatic
AND trim was active for about 10 seconds
, during which the horizontal stabilizer
pitch trim decreased from 6.1 to 3.8 units.
At 23:22:41 UTC, the Captain instructed the FO to select flaps 1 and the DFDR
recorded the flaps started to move
. Three seconds later, the DFDR recorded the
main electric trim moved the stabilizer in the aircraft nose up (ANU) direction for 5
seconds and the pitch trim gradually increased to 4.7 units. ...
At 23:22:48 UTC, the flaps reached position 1 and the left control column stick
shaker stopped briefly. The left AOA recorded 18° (nose up) and the right AOA
22 recorded -3° (nose down). The rate of descent increased up to 3,200 fpm. On the
Captain’s PFD, the low speed barber pole appeared with the top of the pole was
about 285 knots.
At 23:22:54 UTC, the automatic AND trim activated for 8 seconds at a low speed.
.


So MCAS was active at flaps 1, not only flaps UP?
 
Chemist
Posts: 734
Joined: Tue Oct 20, 2015 4:46 am

Re: Updated: Final report of Lion Air JT610 has been released

Fri Oct 25, 2019 8:56 pm

kennyomg wrote:
Wait... what??

At 23:22:33 UTC, the flaps reached the fully retracted position and the automatic
AND trim was active for about 10 seconds
, during which the horizontal stabilizer
pitch trim decreased from 6.1 to 3.8 units.
At 23:22:41 UTC, the Captain instructed the FO to select flaps 1 and the DFDR
recorded the flaps started to move
. Three seconds later, the DFDR recorded the
main electric trim moved the stabilizer in the aircraft nose up (ANU) direction for 5
seconds and the pitch trim gradually increased to 4.7 units. ...
At 23:22:48 UTC, the flaps reached position 1 and the left control column stick
shaker stopped briefly. The left AOA recorded 18° (nose up) and the right AOA
22 recorded -3° (nose down). The rate of descent increased up to 3,200 fpm. On the
Captain’s PFD, the low speed barber pole appeared with the top of the pole was
about 285 knots.
At 23:22:54 UTC, the automatic AND trim activated for 8 seconds at a low speed.
.


So MCAS was active at flaps 1, not only flaps UP?


Main electric trim could have been manually input by the pilot. It doesn't say it was automatic.
 
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flyingturtle
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Re: Updated: Final report of Lion Air JT610 has been released

Fri Oct 25, 2019 9:01 pm

The final report doesn't contain the CVR transcript, no?

Anyway, it's a scathing indictment of Boeing's "safety" "engineering".
Reading accident reports is what calms me down
 
Planetalk
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Re: Updated: Final report of Lion Air JT610 has been released

Fri Oct 25, 2019 9:10 pm

Somewhere outside the rather dull posts by people telling us they were right there's an interesting discussion to be had.

As was to be expected by anyone who's ever read an accident report, blame is shared around amongst all parties, although it is perhaps most unusual to see the aircraft manufacturer receive so much of it, actual design and certification flaws are rarely one of the root causes. It's not surprising that Lionair's training was found wanting, and this FO probably would have been weeded out some time ago in many airlines. Some points I would note:

- The FO also had over 5000 hours total and 4000 ours on type which is food for thought for those who seem to think 1500 hours provides some magical shield against pilot error. I personally feel far more comfortable with a well trained cadet up front than a guy with 1500 hours dusting crops.
- Of course, training systems worldwide need to improve (no s**t Sherlock), I don't think many would have disagreed with that before either of these crashes, it's really not some great revelation. We come back again to the point that it was Boeing who withheld information from pilots and the FAA and ensured these guys knew nothing of MCAS. That wasn't some dodgy third world airline skimping on training, it was a very deliberate, considered, decision by Boeing.
- Boeing well knows the standard of pilots worldwide, and they remain happy to sell planes to these airlines, and were quite happy to reduce training requirements. Boeing are as guilty as anyone for any deficiencies in the standards of pilots.
- There is a question of the intent behind people's actions. It is unlikely the FO deliberately tried to be bad at handling a plane and wasn't fussed if that led to him dying. It is sadly more likely that he lacked some of the skillset to be a good pilot, coupled with a system letting him down. I cannot cut such slack to those in Boeing who made quite deliberate decisions. And if you think there aren't people in management in corporations who don't care if their decisions end up costing lives somewhere down the line, you're being very naive. This guy paid for his mistakes with his life, many of those at Boeing will walk away from all this rich enough never to need to work again. That's why I feel rage at Boeing, and only sympathy for the FO.

Some here seem to think the fact the pilot made some mistakes vindicates their opinion that really MCAS wasn't all that bad as long as you had a half decent pilot. Which is nonsense but you have to admire their persistence. I don't think anyone thought the pilots made no mistakes. What people find unedifying, and frankly ignorant, are statements like 'any half decent pilot could have saved this', 'MCAS should never have led to a crash' and so on ad infinitium the last few months, which are still not backed up by a shred of evidence, and don't seem to be the opinion of anyone whose opinion has any significance in the industry

That this FO made mistakes does not somehow mean only bad crews would have crashed the plane. Indeed, we have plenty of real pilots as opposed to armchair warriors on the internet who have quite unequivocally stated that the pilots should not be blamed. We have the evidence from simulator sessions after the Ethiopian crash when even pilots who knew what was coming struggled or even lost the plane. We have Sully himself who has flown the scenario and came out defending the pilots. We have the public anger of pilots at US airlines towards Boeing for this. I personally, will take those as my references, rather than an anonymous guy on the internet who's never flown a 737 and apparently has nothing to do with their life but smear dead pilots.

Its a very very sad situation and there is a lot to earn all round. One hopes everyone learns from it. And one certainly hopes that no-one in Boeing is today reacting in the same way as some posters here. There is no victory in any of this for anyone, except perhaps any future lives saved by lessons learned.
Last edited by Planetalk on Fri Oct 25, 2019 9:13 pm, edited 1 time in total.
 
musman9853
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Re: Updated: Final report of Lion Air JT610 has been released

Fri Oct 25, 2019 9:12 pm

Wow. So many preventable things, from boeing, lion air, and the pilots, that was responsible for the death of hundreds. stop any one thing in the chain and we wouldnt be in this mess.
Welcome to the City Beautiful.
 
ikramerica
Posts: 15088
Joined: Mon May 23, 2005 9:33 am

Re: Updated: Final report of Lion Air JT610 has been released

Fri Oct 25, 2019 9:23 pm

BEG2IAH wrote:
SwissCanuck wrote:
Last time I got a proper flu I spiked a fever and started feeling... weird. Definitely not confident enough to pour my own glass of water let alone fly a plane.

Plenty to learn from all of this, although I'm sure we all agree the cost was far too high. The only way forward is to make changes and learn from it. Let's hope that happens.


I still can't wrap my mind around how many things went wrong and then some. We can definitely say that the root cause was Boeing's bad design, but why stop there? The actual root cause is greed and an utmost devaluation of the human life. And this applies to all the parties involved, not only Boeing. May all the victims rest in peace, I really hope lessons are learned.

True, but not sure if the PIC flying was about greed or about fear of retribution for calling sick.

Was the unfit FO about greed? Maybe they didn’t want to pay for competency.

Was the escalation of MCAS function about greed or about project creep that didn’t pass through all channels.

Was the downplaying of MCAS about greed or about pleasing their best customers?

I think almost anything can be attributed to greed. But it might be a little cynical sometimes. Humans make bad mistakes.
Of all the things to worry about... the Wookie has no pants.
 
ikramerica
Posts: 15088
Joined: Mon May 23, 2005 9:33 am

Re: Updated: Final report of Lion Air JT610 has been released

Fri Oct 25, 2019 9:39 pm

Planetalk wrote:
Somewhere outside the rather dull posts by people telling us they were right there's an interesting discussion to be had.

As was to be expected by anyone who's ever read an accident report, blame is shared around amongst all parties, although it is perhaps most unusual to see the aircraft manufacturer receive so much of it, actual design and certification flaws are rarely one of the root causes. It's not surprising that Lionair's training was found wanting, and this FO probably would have been weeded out some time ago in many airlines. Some points I would note:

- The FO also had over 5000 hours total and 4000 ours on type which is food for thought for those who seem to think 1500 hours provides some magical shield against pilot error. I personally feel far more comfortable with a well trained cadet up front than a guy with 1500 hours dusting crops.
- Of course, training systems worldwide need to improve (no s**t Sherlock), I don't think many would have disagreed with that before either of these crashes, it's really not some great revelation. We come back again to the point that it was Boeing who withheld information from pilots and the FAA and ensured these guys knew nothing of MCAS. That wasn't some dodgy third world airline skimping on training, it was a very deliberate, considered, decision by Boeing.
- Boeing well knows the standard of pilots worldwide, and they remain happy to sell planes to these airlines, and were quite happy to reduce training requirements. Boeing are as guilty as anyone for any deficiencies in the standards of pilots.
- There is a question of the intent behind people's actions. It is unlikely the FO deliberately tried to be bad at handling a plane and wasn't fussed if that led to him dying. It is sadly more likely that he lacked some of the skillset to be a good pilot, coupled with a system letting him down. I cannot cut such slack to those in Boeing who made quite deliberate decisions. And if you think there aren't people in management in corporations who don't care if their decisions end up costing lives somewhere down the line, you're being very naive. This guy paid for his mistakes with his life, many of those at Boeing will walk away from all this rich enough never to need to work again. That's why I feel rage at Boeing, and only sympathy for the FO.

Some here seem to think the fact the pilot made some mistakes vindicates their opinion that really MCAS wasn't all that bad as long as you had a half decent pilot. Which is nonsense but you have to admire their persistence. I don't think anyone thought the pilots made no mistakes. What people find unedifying, and frankly ignorant, are statements like 'any half decent pilot could have saved this', 'MCAS should never have led to a crash' and so on ad infinitium the last few months, which are still not backed up by a shred of evidence, and don't seem to be the opinion of anyone whose opinion has any significance in the industry

That this FO made mistakes does not somehow mean only bad crews would have crashed the plane. Indeed, we have plenty of real pilots as opposed to armchair warriors on the internet who have quite unequivocally stated that the pilots should not be blamed. We have the evidence from simulator sessions after the Ethiopian crash when even pilots who knew what was coming struggled or even lost the plane. We have Sully himself who has flown the scenario and came out defending the pilots. We have the public anger of pilots at US airlines towards Boeing for this. I personally, will take those as my references, rather than an anonymous guy on the internet who's never flown a 737 and apparently has nothing to do with their life but smear dead pilots.

Its a very very sad situation and there is a lot to earn all round. One hopes everyone learns from it. And one certainly hopes that no-one in Boeing is today reacting in the same way as some posters here. There is no victory in any of this for anyone, except perhaps any future lives saved by lessons learned.

Absolve the airline all you want.

The design was problematic. There was a major problem that could have crashed the plane that was not understood by Lion and not taken seriously.

It should not have been dispatched without a proper repair and documentation and without the crew also knowing what to expect in a failure.

But through a series of errors by the airline and their crew, the squirrelly, improperly repaired plane crashed. A plane that was not properly dispatched.

ET is a different accident. Had JT not crashed, ET definitely would have. But ET wasn’t in a vacuum. We shall see what the investigation reveals. Then you can absolve them.
Of all the things to worry about... the Wookie has no pants.
 
User avatar
PW100
Posts: 4112
Joined: Mon Jan 28, 2002 9:17 pm

Re: Indonesia report on 737 MAX crash faults Boeing design, says Lion Air made mistakes

Fri Oct 25, 2019 9:44 pm

Revelation wrote:
Bloomberg ( https://www.bloomberg.com/news/articles ... rash-probe ) goes more directly at it:

Weeks after a Lion Air jet crashed in the Java Sea, killing all 189 aboard, an airline employee gave investigators photographs meant to show that a crucial repair had been properly performed the day before the disaster.

Yet the pictures may not show what was claimed.

The time displayed in photos of a computer screen in the cockpit of the Boeing Co. 737 Max indicated they had actually been taken before the repair was performed, according to a draft of the final crash report being prepared by Indonesia’s National Transportation Safety Committee, portions of which were reviewed by Bloomberg News.

Investigators were similarly unable to confirm the authenticity of other pictures in the packet, which were supposed to show how a piece of equipment near the jet’s nose had been calibrated, according to the report. There were indications that the pictures depicted a different plane, according to two people familiar with the investigation.

The last thing you want to do is mislead accident investigators, IMO.



Haven't seen the report yet.
Does it mention why the AoA sesnor had to be replaced in the first place?
What was wrong with the inital AoA sensor? As it was removed immediately before the crash, it should have been readily available for the investigation team.

Thanks.
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User avatar
PW100
Posts: 4112
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Re: Reuters: Lion Air JT610 families told 737 MAX design flaws and flight crew deficiencies linked to deadly crash

Fri Oct 25, 2019 9:50 pm

ikramerica wrote:
Well yes. It’s what many have been pointing out since day 2. And we routinely get slammed for even suggesting that despite the situation that MCAS was creating, the handoff to the incompetent FO crashed the plane. Due to both failure of the FO to know how to fly a plane without automation, and failure of the captain to tell him what he was doing to keep the plane aloft.

And worse, the captain seems relatively competent, and had Lion notified him that the previous pilot had to turn off the switches to recover from the same situation, there is no doubt in my mind that he would have done that.

Then again, had that happened, the ET flight would have crashed no matter what since they still would have been unaware of what to do, with the same 2nd seat pilot unfit to be there situation.


From the ET prelim report, it seems the other way around: that he FO was (relatively) more competent than the captain during the short flight.
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morrisond
Posts: 2664
Joined: Thu Jan 07, 2010 12:22 am

Re: Indonesia report on 737 MAX crash faults Boeing design, says Lion Air made mistakes

Fri Oct 25, 2019 9:51 pm

PW100 wrote:
Revelation wrote:
Bloomberg ( https://www.bloomberg.com/news/articles ... rash-probe ) goes more directly at it:

Weeks after a Lion Air jet crashed in the Java Sea, killing all 189 aboard, an airline employee gave investigators photographs meant to show that a crucial repair had been properly performed the day before the disaster.

Yet the pictures may not show what was claimed.

The time displayed in photos of a computer screen in the cockpit of the Boeing Co. 737 Max indicated they had actually been taken before the repair was performed, according to a draft of the final crash report being prepared by Indonesia’s National Transportation Safety Committee, portions of which were reviewed by Bloomberg News.

Investigators were similarly unable to confirm the authenticity of other pictures in the packet, which were supposed to show how a piece of equipment near the jet’s nose had been calibrated, according to the report. There were indications that the pictures depicted a different plane, according to two people familiar with the investigation.

The last thing you want to do is mislead accident investigators, IMO.



Haven't seen the report yet.
Does it mention why the AoA sesnor had to be replaced in the first place?
What was wrong with the inital AoA sensor? As it was removed immediately before the crash, it should have been readily available for the investigation team.

Thanks.


There are links on the previous page - it's 300 pages long. With a full CVR transcript where the pilot mentions he has the flu.
 
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PixelFlight
Posts: 1018
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Re: Indonesia report on 737 MAX crash faults Boeing design, says Lion Air made mistakes

Fri Oct 25, 2019 10:13 pm

PW100 wrote:
Revelation wrote:
Bloomberg ( https://www.bloomberg.com/news/articles ... rash-probe ) goes more directly at it:

Weeks after a Lion Air jet crashed in the Java Sea, killing all 189 aboard, an airline employee gave investigators photographs meant to show that a crucial repair had been properly performed the day before the disaster.

Yet the pictures may not show what was claimed.

The time displayed in photos of a computer screen in the cockpit of the Boeing Co. 737 Max indicated they had actually been taken before the repair was performed, according to a draft of the final crash report being prepared by Indonesia’s National Transportation Safety Committee, portions of which were reviewed by Bloomberg News.

Investigators were similarly unable to confirm the authenticity of other pictures in the packet, which were supposed to show how a piece of equipment near the jet’s nose had been calibrated, according to the report. There were indications that the pictures depicted a different plane, according to two people familiar with the investigation.

The last thing you want to do is mislead accident investigators, IMO.



Haven't seen the report yet.
Does it mention why the AoA sesnor had to be replaced in the first place?
What was wrong with the inital AoA sensor? As it was removed immediately before the crash, it should have been readily available for the investigation team.

Thanks.

The first sensor was analysed and was found with an open circuit in one the resolver's coil that depend on the temperature of operation. That fault was consistent with the observed malfunction while on the aircraft.

The second sensor was not identified in the wreckage, but the procedure for the calibration at the repair facility was identified as defective by not telling that the sensor REL/ABS switch must be set to the absolute position to make the calibration. The two tests that was done by the investigators was able to reproduce the erratic offset while doing the calibration by setting the the REL/ABS switch in relative position. The erratic offset was not detectable with the tools and procedure used at the repair facility. The erratic offset was identifiable with the two possible methods to test the sensors after installation on the aircraft. No record of such test was identified for the installation. The erratic offset was consistent with the FDR records.

So, as improbable as it seem, the first bad AoA sensor was replaced by a second bad AoA sensor that passed undetected trough the repair quality control, and that after mounted on the aircraft it was most probably either not tested or either tested but the erratic result ignored.
Last edited by PixelFlight on Fri Oct 25, 2019 10:21 pm, edited 1 time in total.
:stirthepot: 737-8 MAX: "For all speeds higher than 220 Kts and trim set at a value of 2.5 units, the difficulity level of turning the manual trim wheel was level A (trim wheel not movable)." :stirthepot:
 
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PW100
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Re: Updated: Final report of Lion Air JT610 has been released

Fri Oct 25, 2019 10:15 pm

morrisond wrote:
It's revealing after the report has been released how quiet it's gotten in here.
These are my main three takeaways in regards to the pilots actions:
#1 The Pilot did not review the issues from the Previous Flight - that is a huge No-no. If he had he probably would have had the knowledge that would have saved everyone on board.
#2 The Co-Pilot was cited as basically being incompetent and did not even have a mastery over the basics of Manual flight (did not know how to even use Manual Electric Trim properly) therefore should not have even be licensed as a pilot but kept getting passes through the Lion Air system.
#3 While the Pilot missed the review of the previous flight and showed relatively okay skills in the cockpit - it's one thing to look at the traces and see him counteracting MCAS activation 22 times - it's another thing to read about it in the timeline and say - why the hell didn't he throw the switches?

Then you read in the detailed CVR transcript that he admitted having the flu - which makes the fact he missed it 22 times and didn't brief his co-pilot properly on handover more understandable - but there is no way in hell he should have been in a cockpit. The Flu would have made him functionally impaired and possibly no better than drunk off his ass.
It's an incredibly detailed report - but after reading it you still think the pilots actions were not egregiously bad - symptomatic of a very broken training system I don't know what to say.

Boeing is still the root cause - but neither of those pilots should have been in that cockpit that day.


#1 Agree on the first part. Not sure though if that would have changed much considering his lack of CRM and in the hand over to the FO . . .

#2 Not sure if there is any mentioning in the report, but in his defence, a) the captain did not inform him on his work around, and b) he might have formed the opinion that control column force would stop STS trimming. With MCAS undisclosed, it could be seen as STS function. Since the captain had not thrown the switches, there was no reason for him to suspect that whatever was going on could not be handled by control column. On the other hand, with the control column getting heavier and heavier, at some point that should have been a strong indicator of runaway-trim, so he should have thrown the switches as part of the runaway trim NNC. But if he did not recall the unreliable airspeed checklist, it can be no surprise that he did not remember the runaway trim checklist.

#3. Haven't read the report yet, but I find this a rather soft reasoning. Because it can be turned around to ask why throw the switchers when your manual electric trimming is still working to your advantage. Perhaps throwing the switches could take away the one thing that is still working for him. Remember, they did not have the Boeing Bulletin nor the AD, which made missing link between the warnings, trim behaviour and the run-away trim/MCAS and the cut-out switches.

Boeing is still the root cause - but neither of those pilots should have been in that cockpit that day.

I haven't read the report yet, but I can perfectly accept that line of verbiage with the key words: Root Cause.

And it very seems crew performance was (much) worse than many (including myself) intially thought. I guess the prelim report masked some of that, though I don't understand why the CVR transcript wasn't reported to a somewhat deeper level. But kudos to the Indonesian team in not leaving that under the carpet (as some feared) in the final report.
Immigration officer: "What's the purpose of your visit to the USA?" Spotter: "Shooting airliners with my Canon!"
 
DualQual
Posts: 714
Joined: Sun Mar 05, 2006 6:10 pm

Re: Updated: Final report of Lion Air JT610 has been released

Fri Oct 25, 2019 10:39 pm

Planetalk wrote:
Somewhere outside the rather dull posts by people telling us they were right there's an interesting discussion to be had.

As was to be expected by anyone who's ever read an accident report, blame is shared around amongst all parties, although it is perhaps most unusual to see the aircraft manufacturer receive so much of it, actual design and certification flaws are rarely one of the root causes. It's not surprising that Lionair's training was found wanting, and this FO probably would have been weeded out some time ago in many airlines. Some points I would note:

- The FO also had over 5000 hours total and 4000 ours on type which is food for thought for those who seem to think 1500 hours provides some magical shield against pilot error. I personally feel far more comfortable with a well trained cadet up front than a guy with 1500 hours dusting crops.


I’d like to point out that this is an idiotic statement. The guy with 1500 hours dusting crops has spent 1500 hours doing difficult, hands on flying. Ironically that type of pilot may have been the type to save this airplane. Because he could, you know, actually fly.
There's no known cure for stupid
 
BEG2IAH
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Re: Updated: Final report of Lion Air JT610 has been released

Fri Oct 25, 2019 10:42 pm

ikramerica wrote:
Was the unfit FO about greed? Maybe they didn’t want to pay for competency.
Was the escalation of MCAS function about greed or about project creep that didn’t pass through all channels.
Was the downplaying of MCAS about greed or about pleasing their best customers?
I think almost anything can be attributed to greed. But it might be a little cynical sometimes. Humans make bad mistakes.


Let's not take that literally, use your imagination. Those dead pilots would not have behaved like you describe them here without their airline's leadership being greedy and not really caring about their employees or customers.

In addition to the greed, I mentioned devaluation of the human life. Boeing has proven that they didn't care - whoever: management, engineers, leadership, all of them. Their actions spoke very clearly and loudly that they cared very little about safety. That's what we economists call a 'revealed preference'. Had they cared the 737 Max MCAS would not have been certified. They had many chances to stop it but "their management pushed them." What a lousy excuse. Even Boeing's actions and statements following the two crashes were made with a goal of saving their asses.

I agree, it's only human to make mistakes, but shoving things under the rug to not harm cash flow is sick. Well, they saved a lot. What is it now - 9 billion and counting?
Flying at the cruising altitude is (mostly) boring. I wish all flights were nothing but endless take offs and landings every 10 minutes or so.
 
frmrCapCadet
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Re: Updated: Final report of Lion Air JT610 has been released

Fri Oct 25, 2019 11:01 pm

I have mentioned several times, mainline passenger aviation seems to depend upon $15 million simulators or iPads. Numerous $25-100K simulators, and lots of time initially and a fair amount per year would do a lot better. Or an open book classroom, calling for memory items, many of them, and fast, one after another. Take the class until you get 100% right.
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kennyomg
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Re: Updated: Final report of Lion Air JT610 has been released

Fri Oct 25, 2019 11:08 pm

Chemist wrote:
kennyomg wrote:
Wait... what??

At 23:22:33 UTC, the flaps reached the fully retracted position and the automatic
AND trim was active for about 10 seconds
, during which the horizontal stabilizer
pitch trim decreased from 6.1 to 3.8 units.
At 23:22:41 UTC, the Captain instructed the FO to select flaps 1 and the DFDR
recorded the flaps started to move
. Three seconds later, the DFDR recorded the
main electric trim moved the stabilizer in the aircraft nose up (ANU) direction for 5
seconds and the pitch trim gradually increased to 4.7 units. ...
At 23:22:48 UTC, the flaps reached position 1 and the left control column stick
shaker stopped briefly. The left AOA recorded 18° (nose up) and the right AOA
22 recorded -3° (nose down). The rate of descent increased up to 3,200 fpm. On the
Captain’s PFD, the low speed barber pole appeared with the top of the pole was
about 285 knots.
At 23:22:54 UTC, the automatic AND trim activated for 8 seconds at a low speed.
.


So MCAS was active at flaps 1, not only flaps UP?


Main electric trim could have been manually input by the pilot. It doesn't say it was automatic.

How do you infer manual trim from "automatic AND trim" in the quote?
 
MSPNWA
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Re: Updated: Final report of Lion Air JT610 has been released

Sat Oct 26, 2019 12:26 am

BEG2IAH wrote:
In addition to the greed, I mentioned devaluation of the human life. Boeing has proven that they didn't care - whoever: management, engineers, leadership, all of them. Their actions spoke very clearly and loudly that they cared very little about safety. That's what we economists call a 'revealed preference'. Had they cared the 737 Max MCAS would not have been certified. They had many chances to stop it but "their management pushed them." What a lousy excuse. Even Boeing's actions and statements following the two crashes were made with a goal of saving their asses.

I agree, it's only human to make mistakes, but shoving things under the rug to not harm cash flow is sick. Well, they saved a lot. What is it now - 9 billion and counting?


You're certainly entitled to your opinion, but I think an economist should know more than most that everything has a price--safety/life included. It isn't automatically greed. It's not downplaying the value of life. It's the reality of the life we face. Saying Boeing doesn't care is a slanderous exaggeration. Getting it wrong =/= not caring. I expect better from a fellow economist.
 
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aemoreira1981
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Re: Updated: Final report of Lion Air JT610 has been released

Sat Oct 26, 2019 1:44 am

While there is blame to go all around...how is it that the first officer was allowed to fly?
 
morrisond
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Re: Updated: Final report of Lion Air JT610 has been released

Sat Oct 26, 2019 2:37 am

aemoreira1981 wrote:
While there is blame to go all around...how is it that the first officer was allowed to fly?


I don't think you could actually call what he did flying. I have no clue how he got through basic training.

The pilot should not have been anywhere near that cockpit either with the Flu. That would have seriously affected his ability to handle the situation.
 
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zeke
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Re: Indonesia report on 737 MAX crash faults Boeing design, says Lion Air made mistakes

Sat Oct 26, 2019 4:30 am

PixelFlight wrote:
The second sensor was not identified in the wreckage, but the procedure for the calibration at the repair facility was identified as defective by not telling that the sensor REL/ABS switch must be set to the absolute position to make the calibration. The two tests that was done by the investigators was able to reproduce the erratic offset while doing the calibration by setting the the REL/ABS switch in relative position. The erratic offset was not detectable with the tools and procedure used at the repair facility. The erratic offset was identifiable with the two possible methods to test the sensors after installation on the aircraft. No record of such test was identified for the installation. The erratic offset was consistent with the FDR records.


To be fair to the airline, the procedure they followed with the sensor is used by every airline. Parts like this are sent to shops that specialise with these repairs and overhauls and the release certification stating it is serviceable means exactly that.

That information in the report is really the foundation of the crash.

The FAA should come under fire for the oversight of the repair facility as well as the system certification.
Human rights lawyers are "ambulance chasers of the very worst kind.'" - Sky News
 
MSPNWA
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Re: Updated: Final report of Lion Air JT610 has been released

Sat Oct 26, 2019 4:49 am

I haven't been able to dig deep into the report, but what I've seen so far paints the picture of a systematic failure. I think it's a textbook example of one. There's so many links in the chain that it's hard to grasp. This isn't one thing. This is dozens of things put together, all playing their part. To me it feels even more tragic because there were so many opportunities to avoid disaster.
 
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Finn350
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Re: Indonesia report on 737 MAX crash faults Boeing design, says Lion Air made mistakes

Sat Oct 26, 2019 6:15 am

zeke wrote:
PixelFlight wrote:
The second sensor was not identified in the wreckage, but the procedure for the calibration at the repair facility was identified as defective by not telling that the sensor REL/ABS switch must be set to the absolute position to make the calibration. The two tests that was done by the investigators was able to reproduce the erratic offset while doing the calibration by setting the the REL/ABS switch in relative position. The erratic offset was not detectable with the tools and procedure used at the repair facility. The erratic offset was identifiable with the two possible methods to test the sensors after installation on the aircraft. No record of such test was identified for the installation. The erratic offset was consistent with the FDR records.


To be fair to the airline, the procedure they followed with the sensor is used by every airline. Parts like this are sent to shops that specialise with these repairs and overhauls and the release certification stating it is serviceable means exactly that.

That information in the report is really the foundation of the crash.

The FAA should come under fire for the oversight of the repair facility as well as the system certification.


The REL/ABS switch is not in the sensor. It is in the Peak Electronics SRI-201B (Model 7724-00-2) (Peak API) test equipment used to calibrate the sensor.

It is apparent that the Lion Air engineer didn't test the sensor after installing (see for example report p. 36)

The test equipment (AOA test fixture SPL-1917) was not available in Denpasar therefore, the engineer in Denpasar used the alternative method. The alternative method is performed by deflecting the AOA vane to the fully up, center, and fully down positions while verifying the indication on the SMYD computer for each position. The engineer did not record the indication on the SMYD computer during the installation test.
The engineer in Denpasar conducted the heater test by dropping water onto the AOA vane with result that it passed. The engineer performed the BITE test on the FMC CDU which showed “No Current Faults”.
The engineer in Denpasar provided the investigation several photos including of the Captain’s PFD that was claimed to be taken after the AOA sensor replacement and of the SMYD during the installation test. However, the time shown on the Captain’s PFD was the time before arrival of AOA sensor spare part and the investigation confirmed that the SMYD photos were not of the accident aircraft.
 
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zeke
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Re: Indonesia report on 737 MAX crash faults Boeing design, says Lion Air made mistakes

Sat Oct 26, 2019 6:35 am

Finn350 wrote:
The REL/ABS switch is not in the sensor. It is in the Peak Electronics SRI-201B (Model 7724-00-2) (Peak API) test equipment used to calibrate the sensor.

It is apparent that the Lion Air engineer didn't test the sensor after installing (see for example report p. 36)


I never said the switch was on the sensor. I simply stated that the airline received a repaired component from a specialist facility. That facility is under FAA oversight, using FAA repair procedures and FAA approved quality assurance procedures.

For the sensor to leave the repair facility it not only need to be repaired, it needs precise calibration, and it requires quality assurance testing. Those procedures would have different technicians repairing and testing it.

The on aircraft testing is just a gross error test to make sure it is electrically connected correctly, it has nothing to do with precise calibration of the probe. You cannot control the attitude of the aircraft unless you jack the aircraft up in a hanger. You simply don’t do that to replace a sensor.

These probes are designed to be replaced without the need of extensive ground equipment or facilities in the field for example after a bird strike.
Human rights lawyers are "ambulance chasers of the very worst kind.'" - Sky News
 
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Finn350
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Re: Indonesia report on 737 MAX crash faults Boeing design, says Lion Air made mistakes

Sat Oct 26, 2019 6:51 am

zeke wrote:
Finn350 wrote:
The REL/ABS switch is not in the sensor. It is in the Peak Electronics SRI-201B (Model 7724-00-2) (Peak API) test equipment used to calibrate the sensor.

It is apparent that the Lion Air engineer didn't test the sensor after installing (see for example report p. 36)


I never said the switch was on the sensor. I simply stated that the airline received a repaired component from a specialist facility. That facility is under FAA oversight, using FAA repair procedures and FAA approved quality assurance procedures.


No, but PixelFlight said that in the other post I quoted.


zeke wrote:
The on aircraft testing is just a gross error test to make sure it is electrically connected correctly, it has nothing to do with precise calibration of the probe. You cannot control the attitude of the aircraft unless you jack the aircraft up in a hanger. You simply don’t do that to replace a sensor.

These probes are designed to be replaced without the need of extensive ground equipment or facilities in the field for example after a bird strike.


In the text I quoted there are two procedure for on-aircraft testing. If either of them were performed, it would have shown that the sensor was broken.
 
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zeke
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Re: Indonesia report on 737 MAX crash faults Boeing design, says Lion Air made mistakes

Sat Oct 26, 2019 8:05 am

Finn350 wrote:
In the text I quoted there are two procedure for on-aircraft testing. If either of them were performed, it would have shown that the sensor was broken.


Please don’t treat me like a 5 year old. I have read the report, the replacement sensor was not broken.

What the report says is the replacement sensor was not broken, it was serviceable, however with a large bias because of the way it was calibrated.

When on the ground at zero speed it is normal for AOA sensors to register high angles, in the absence of airflow they will rest at any angle, often near 90 degrees.

The field test s not a calibration exercise, it is to ensure the cables have been correctly connected. Calibration and functional testing of that calibration is performed at the avionics shop, not on the aircraft. There is no way for someone to calibrate these sensors in the field.
Human rights lawyers are "ambulance chasers of the very worst kind.'" - Sky News
 
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Finn350
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Re: Indonesia report on 737 MAX crash faults Boeing design, says Lion Air made mistakes

Sat Oct 26, 2019 8:08 am

zeke wrote:
Finn350 wrote:
In the text I quoted there are two procedure for on-aircraft testing. If either of them were performed, it would have shown that the sensor was broken.


Please don’t treat me like a 5 year old. I have read the report, the replacement sensor was not broken.

What the report says is the replacement sensor was not broken, it was serviceable, however with a large bias because of the way it was calibrated.

When on the ground at zero speed it is normal for AOA sensors to register high angles, in the absence of airflow they will rest at any angle, often near 90 degrees.

The field test s not a calibration exercise, it is to ensure the cables have been correctly connected. Calibration and functional testing of that calibration is performed at the avionics shop.



So you are saying that even if the test was performed (deflecting the AOA vane to the fully up, center, and fully down positions while verifying the indication on the SMYD computer for each position) the sensor bias would not have been noticed?
 
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zeke
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Re: Indonesia report on 737 MAX crash faults Boeing design, says Lion Air made mistakes

Sat Oct 26, 2019 9:35 am

Finn350 wrote:
So you are saying that even if the test was performed (deflecting the AOA vane to the fully up, center, and fully down positions while verifying the indication on the SMYD computer for each position) the sensor bias would not have been noticed?


Of course, it is a gross error check to see it’s installed correctly, not a verification of the exact readouts.

By way of background the hole pattern of the screws and the unique pin pattern on the plug make it “impossible” to install incorrectly.

The sensor was working correctly in terms of physical range and direction of movement, it was just over reading.

Typically such a test would be done by an avionics licenced person in the cockpit and a unqualified or limited qualification mechanic moving the sensor.

No different to say a flight control check, after they are worked on we do an operational test to see they are moving full and free in the correct directions, we don’t get out there and measure the actual angles of deflection, that is done during rigging. Have one person in the cockpit moving the controls and another outside observing.
Human rights lawyers are "ambulance chasers of the very worst kind.'" - Sky News
 
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Finn350
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Re: Indonesia report on 737 MAX crash faults Boeing design, says Lion Air made mistakes

Sat Oct 26, 2019 9:53 am

zeke wrote:
Finn350 wrote:
So you are saying that even if the test was performed (deflecting the AOA vane to the fully up, center, and fully down positions while verifying the indication on the SMYD computer for each position) the sensor bias would not have been noticed?


Of course, it is a gross error check to see it’s installed correctly, not a verification of the exact readouts.

By way of background the hole pattern of the screws and the unique pin pattern on the plug make it “impossible” to install incorrectly.

The sensor was working correctly in terms of physical range and direction of movement, it was just over reading.

Typically such a test would be done by an avionics licenced person in the cockpit and a unqualified or limited qualification mechanic moving the sensor.

No different to say a flight control check, after they are worked on we do an operational test to see they are moving full and free in the correct directions, we don’t get out there and measure the actual angles of deflection, that is done during rigging. Have one person in the cockpit moving the controls and another outside observing.


I beg to disagree. What is the point to check SMYD readouts if not to check whether there is a gross disagreement.
 
asdf
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Re: Indonesia report on 737 MAX crash faults Boeing design, says Lion Air made mistakes

Sat Oct 26, 2019 9:59 am

Finn350 wrote:
I beg to disagree. What is the point to check SMYD readouts if not to check whether there is a gross disagreement.


to see if the movement itself is working
the point to check SMDY readouts is to make shure that there has not happened a basical error during installing and movement is impossible or cables maybe have not been connected

calibration of the readout can only be done in the workshop
unit is sealed
 
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zeke
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Re: Indonesia report on 737 MAX crash faults Boeing design, says Lion Air made mistakes

Sat Oct 26, 2019 10:21 am

Finn350 wrote:
What is the point to check SMYD readouts if not to check whether there is a gross disagreement.


Because that is the computer the sensor is connected to.
Human rights lawyers are "ambulance chasers of the very worst kind.'" - Sky News
 
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Re: Updated: Final report of Lion Air JT610 has been released

Sat Oct 26, 2019 10:46 am

Essentially, the "root cause" of the crash is a failed AoA sensor. The reason that the AoA sensor was able to cause the crash is due to a poor design by Boeing and poor oversight by the FAA. Given the root cause and the poor MCAS design/oversight, the reason that the crash occurred is that the Captain had the flu and was likely impaired due to the sickness and the FO was incompetent and shouldn't have been certified to fly a commercial aircraft.

If Boeing had properly designed MCAS and the FAA had done their job of oversight, the conditions wouldn't have been possible for the crash to occur. If the repair facility had done a proper repair there wouldn't have been a failure of the AoA sensor. If the Lion Air mechanic had done the proper checks he would have discovered the bad AoA sensor. I would assign "fault" basically in that order. However, what can not be overlooked is that crew on that day would have likely crashed due to any serious failure that required good CRM, an alert and unimpaired captain and a competent FO to recover from.
 
planecane
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Re: Updated: Final report of Lion Air JT610 has been released

Sat Oct 26, 2019 10:49 am

kennyomg wrote:
Wait... what??

At 23:22:33 UTC, the flaps reached the fully retracted position and the automatic
AND trim was active for about 10 seconds
, during which the horizontal stabilizer
pitch trim decreased from 6.1 to 3.8 units.
At 23:22:41 UTC, the Captain instructed the FO to select flaps 1 and the DFDR
recorded the flaps started to move
. Three seconds later, the DFDR recorded the
main electric trim moved the stabilizer in the aircraft nose up (ANU) direction for 5
seconds and the pitch trim gradually increased to 4.7 units. ...
At 23:22:48 UTC, the flaps reached position 1 and the left control column stick
shaker stopped briefly. The left AOA recorded 18° (nose up) and the right AOA
22 recorded -3° (nose down). The rate of descent increased up to 3,200 fpm. On the
Captain’s PFD, the low speed barber pole appeared with the top of the pole was
about 285 knots.
At 23:22:54 UTC, the automatic AND trim activated for 8 seconds at a low speed.
.


So MCAS was active at flaps 1, not only flaps UP?


My assumption would be that the logic checks flaps position before the MCAS cycle starts and that it will complete the cycle even if flaps are deployed in the meantime. Either that or it is active during the transition to flaps 1 and stops when the flaps have reached the flaps 1 position.
 
morrisond
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Re: Indonesia report on 737 MAX crash faults Boeing design, says Lion Air made mistakes

Sat Oct 26, 2019 10:58 am

zeke wrote:
Finn350 wrote:
What is the point to check SMYD readouts if not to check whether there is a gross disagreement.


Because that is the computer the sensor is connected to.


So you are saying it's okay to ignore the approved installation procedure?

What if the Vane had been damaged since being repaired?

Zeke - as an airline Pilot I can't believe you would be okay with this.

Are you saying you would be fine dispatching with a part that was not installed using the approved procedure?

How the hell is Boeing supposed to design around that?
 
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Re: Indonesia report on 737 MAX crash faults Boeing design, says Lion Air made mistakes

Sat Oct 26, 2019 11:12 am

Finn350 wrote:
zeke wrote:
Finn350 wrote:
The REL/ABS switch is not in the sensor. It is in the Peak Electronics SRI-201B (Model 7724-00-2) (Peak API) test equipment used to calibrate the sensor.

You are right, I have wrote my summary I bit to fast, sorry for the confusion.
:stirthepot: 737-8 MAX: "For all speeds higher than 220 Kts and trim set at a value of 2.5 units, the difficulity level of turning the manual trim wheel was level A (trim wheel not movable)." :stirthepot:
 
SwissCanuck
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Re: Updated: Final report of Lion Air JT610 has been released

Sat Oct 26, 2019 11:26 am

planecane wrote:
Essentially, the "root cause" of the crash is a failed AoA sensor. The reason that the AoA sensor was able to cause the crash is due to a poor design by Boeing and poor oversight by the FAA. Given the root cause and the poor MCAS design/oversight, the reason that the crash occurred is that the Captain had the flu and was likely impaired due to the sickness and the FO was incompetent and shouldn't have been certified to fly a commercial aircraft.

If Boeing had properly designed MCAS and the FAA had done their job of oversight, the conditions wouldn't have been possible for the crash to occur. If the repair facility had done a proper repair there wouldn't have been a failure of the AoA sensor. If the Lion Air mechanic had done the proper checks he would have discovered the bad AoA sensor. I would assign "fault" basically in that order. However, what can not be overlooked is that crew on that day would have likely crashed due to any serious failure that required good CRM, an alert and unimpaired captain and a competent FO to recover from.


Well said. I would have added at least a line about training and communication issues however.
 
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Re: Indonesia report on 737 MAX crash faults Boeing design, says Lion Air made mistakes

Sat Oct 26, 2019 11:27 am

Finn350 wrote:
In the text I quoted there are two procedure for on-aircraft testing. If either of them were performed, it would have shown that the sensor was broken.

One of the procedure was relatively simple. I would not be surprised that it was in fact performed but that the result was so unbelievable that the guy did ignore it. It could have think that escalating the issue will be a mess for everyone, and this was just yet an another issue with all those AoA sensor that there replace routinely. Waring: this is pure speculation from me.

More pragmatically, those sensors must be designed to not have to be calibrated and to have no way to mount any part not exactly at the designed position.
:stirthepot: 737-8 MAX: "For all speeds higher than 220 Kts and trim set at a value of 2.5 units, the difficulity level of turning the manual trim wheel was level A (trim wheel not movable)." :stirthepot:
 
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Re: Indonesia report on 737 MAX crash faults Boeing design, says Lion Air made mistakes

Sat Oct 26, 2019 11:43 am

PixelFlight wrote:
More pragmatically, those sensors must be designed to not have to be calibrated and to have no way to mount any part not exactly at the designed position.

It’s very hard, if not impossible, to design sensors (doesn’t really matter the type) that don’t require calibration. Calibration is necessary to translate a sensor’s measurement into something a human (and other computer systems) can actually understand and know what to do with.
 
planecane
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Re: Indonesia report on 737 MAX crash faults Boeing design, says Lion Air made mistakes

Sat Oct 26, 2019 11:58 am

Polot wrote:
PixelFlight wrote:
More pragmatically, those sensors must be designed to not have to be calibrated and to have no way to mount any part not exactly at the designed position.

It’s very hard, if not impossible, to design sensors (doesn’t really matter the type) that don’t require calibration. Calibration is necessary to translate a sensor’s measurement into something a human (and other computer systems) can actually understand and know what to do with.


I concur. Due to manufacturing tolerances in the components used to make any electronic sensor, calibration after final assembly or repair is always going to be required. To avoid it you'd have to have such tight tolerances that the component yield would be so low that it would increase the cost of each component by a factor of at least 10 if not more. That would result in the sensor costing a lot more as the additional cost of each component is added up.

Properly performed calibration as specified by the manufacturer will lead to a consistent output for the given input range.
 
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Polot
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Re: Indonesia report on 737 MAX crash faults Boeing design, says Lion Air made mistakes

Sat Oct 26, 2019 12:04 pm

planecane wrote:
Polot wrote:
PixelFlight wrote:
More pragmatically, those sensors must be designed to not have to be calibrated and to have no way to mount any part not exactly at the designed position.

It’s very hard, if not impossible, to design sensors (doesn’t really matter the type) that don’t require calibration. Calibration is necessary to translate a sensor’s measurement into something a human (and other computer systems) can actually understand and know what to do with.


I concur. Due to manufacturing tolerances in the components used to make any electronic sensor, calibration after final assembly or repair is always going to be required. To avoid it you'd have to have such tight tolerances that the component yield would be so low that it would increase the cost of each component by a factor of at least 10 if not more. That would result in the sensor costing a lot more as the additional cost of each component is added up.

Properly performed calibration as specified by the manufacturer will lead to a consistent output for the given input range.

Yes, you with a calibration less sensor you are basically relying on blind faith that it works the way you expect it to.

All these discussion is about sensors making continuous measurements btw, not simple on/off sensors.
 
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PixelFlight
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Re: Indonesia report on 737 MAX crash faults Boeing design, says Lion Air made mistakes

Sat Oct 26, 2019 12:59 pm

Polot wrote:
planecane wrote:
Polot wrote:
It’s very hard, if not impossible, to design sensors (doesn’t really matter the type) that don’t require calibration. Calibration is necessary to translate a sensor’s measurement into something a human (and other computer systems) can actually understand and know what to do with.


I concur. Due to manufacturing tolerances in the components used to make any electronic sensor, calibration after final assembly or repair is always going to be required. To avoid it you'd have to have such tight tolerances that the component yield would be so low that it would increase the cost of each component by a factor of at least 10 if not more. That would result in the sensor costing a lot more as the additional cost of each component is added up.

Properly performed calibration as specified by the manufacturer will lead to a consistent output for the given input range.

Yes, you with a calibration less sensor you are basically relying on blind faith that it works the way you expect it to.

All these discussion is about sensors making continuous measurements btw, not simple on/off sensors.

I have worked with a lot of sensors in the industry that require no calibration at all, including high precision absolute angle sensors. Most of the time the issue is how the mechanic is designed to ensure that every parts can only be mounted in the expected position.
:stirthepot: 737-8 MAX: "For all speeds higher than 220 Kts and trim set at a value of 2.5 units, the difficulity level of turning the manual trim wheel was level A (trim wheel not movable)." :stirthepot:
 
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zeke
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Re: Indonesia report on 737 MAX crash faults Boeing design, says Lion Air made mistakes

Sat Oct 26, 2019 1:39 pm

morrisond wrote:

So you are saying it's okay to ignore the approved installation procedure?

What if the Vane had been damaged since being repaired?

Zeke - as an airline Pilot I can't believe you would be okay with this.

Are you saying you would be fine dispatching with a part that was not installed using the approved procedure?

How the hell is Boeing supposed to design around that?


The report states there are two approved procedures to install the replacement sensor, and they followed one of them.

If this was another sensor like a radar altimeter, the procedure would be very similar. They would remove the old one, install a replacement and do a gross error check. They would not get a measuring tape out and measure the height of the antenna from the ground. It’s just a functional test to see its working. The calibration is done in an approved repair facility.
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PW100
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Re: Indonesia report on 737 MAX crash faults Boeing design, says Lion Air made mistakes

Sat Oct 26, 2019 2:16 pm

zeke wrote:
morrisond wrote:
. . . .


The report states there are two approved procedures to install the replacement sensor, and they followed one of them.

If this was another sensor like a radar altimeter, the procedure would be very similar. They would remove the old one, install a replacement and do a gross error check. They would not get a measuring tape out and measure the height of the antenna from the ground. It’s just a functional test to see its working. The calibration is done in an approved repair facility.


Would it be expected that a "gross error check" would/should be able to catch a 22 degrees bias?
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zoom321
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Re: Updated: Final report of Lion Air JT610 has been released

Sat Oct 26, 2019 2:20 pm

Does the report indicate if the maintenace issues were due to Lion mechanics not following boeing manual or is it the boeing manual that is inadequate ?
 
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Finn350
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Re: Indonesia report on 737 MAX crash faults Boeing design, says Lion Air made mistakes

Sat Oct 26, 2019 2:24 pm

zeke wrote:
morrisond wrote:

So you are saying it's okay to ignore the approved installation procedure?

What if the Vane had been damaged since being repaired?

Zeke - as an airline Pilot I can't believe you would be okay with this.

Are you saying you would be fine dispatching with a part that was not installed using the approved procedure?

How the hell is Boeing supposed to design around that?


The report states there are two approved procedures to install the replacement sensor, and they followed one of them.


They didn't follow the approved installation procedure! The engineer should have checked and recorded the angle deflection test values of AOA sensor via the SMYD to ensure that test results were within tolerance. See p. 38 of the report.

During the replacement of the left AOA sensor, the installation test of the AOA sensor required the engineer to check the angle deflection of AOA sensor via the SMYD. The BAT LMPM required the engineer to record the test values to ensure that the test results were within tolerance. The engineer did not record the value of the AOA angle deflection during the AOA sensor installation test.
 
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Polot
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Re: Updated: Final report of Lion Air JT610 has been released

Sat Oct 26, 2019 2:27 pm

zoom321 wrote:
Does the report indicate if the maintenace issues were due to Lion mechanics not following boeing manual or is it the boeing manual that is inadequate ?

Both the vender in the US where the sources the replacement AOA vane and Lion air did not follow/performed approved and required procedures. From what I gather they are not 100% sure what Lionair actually did, as evidence suggests Lionair was trying to cover their tracks after the fact.
 
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PixelFlight
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Re: Updated: Final report of Lion Air JT610 has been released

Sat Oct 26, 2019 2:28 pm

zoom321 wrote:
Does the report indicate if the maintenace issues were due to Lion mechanics not following boeing manual or is it the boeing manual that is inadequate ?

The report has detailed explanations how the FAA certified (well, not anymore) Xtra Aerospace mis-calibrated the AoA sensor and certified it for operation.
:stirthepot: 737-8 MAX: "For all speeds higher than 220 Kts and trim set at a value of 2.5 units, the difficulity level of turning the manual trim wheel was level A (trim wheel not movable)." :stirthepot:

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