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PixelFlight
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sat Jan 19, 2019 11:47 am

PlanesNTrains wrote:
SimpleFlying wrote:


Time for me to make a new tinfoil hat. The news keeps destroying the ones I make.

Easy: there are now writing the recorder with voices mastered from flight simulator and cheap actors that believe making a new video game play action...:-D
 
salttee
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sat Jan 19, 2019 12:48 pm

sgrow787 wrote:
If the sensors that help detect a stall or impending stall - ie AOA sensors - aren't working, then how can you pay attention to them? If you've got a stall prevention system - ie MCAS - that uses data from those sensors, _and_ it can't - whether a sw bug or a bad design - effectively choose the good sensor out of two available, .... what are you as a pilot suppose to do?

Fly pitch and power, disable stab trim, land asap.

sgrow787 wrote:
I believe MCAS was designed to be using source selection on two redundant AOA sensors, and that somehow Boeing didn't do all the work - system design, software development, verification - to make it a realization.

That is an unhinged belief. You have no insight into what the MCAS designers wanted as far as AOA reliability; but we must assume that they knew how the rest of the 737 flight system was designed. The solution to a failing AOA sensor is to disable stab trim. It is not a problem without a solution.
 
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SomebodyInTLS
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sat Jan 19, 2019 1:28 pm

salttee wrote:
sgrow787 wrote:
is it possible the pilots of JT610 thought their plane was in a stall?

They knew they weren't in a stall. They were flying straight and level for 7? minutes and were flying pitch and power with a bit of excessive power; they were at around 300kts if I remember correctly. Also they had asked the tower for groundspeed.


AF447 also "knew" they were not in a stall...
"As with most things related to aircraft design, it's all about the trade-offs and much more nuanced than A.net likes to make out."
 
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FlyXLsa
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sat Jan 19, 2019 1:55 pm

PixelFlight wrote:
Time for me to make a new tinfoil hat. The news keeps destroying the ones I make.
Easy: there are now writing the recorder with voices mastered from flight simulator and cheap actors that believe making a new video game play action...:-D


Image

:lol:
Whiskey-Oscar-Oscar-Foxtrot
 
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FlyXLsa
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sat Jan 19, 2019 2:26 pm

salttee wrote:
sgrow787 wrote:
...is it possible the pilots of JT610 thought their plane was in a stall?

They knew they weren't in a stall. They were flying straight and level for 7? minutes and were flying pitch and power with a bit of excessive power; they were at around 300kts if I remember correctly. Also they had asked the tower for groundspeed.


Correct. And... MCAS is not Stall Prevention System as I've stated previously. It is a Flight Augmentation System. They were nowhere close to a stall. They had a nose down problem, not a nose up ( which can lead to a stall) problem.

Doesn't the Tower just read back the groundspeed and altitude from the ADS-B? So if you have Unreliable Airspeed and Altitude Disagree, I don't think that data can be trusted. I'd much rather look at the GPS, my Foreflight iPad App or even my phone to confirm Groundspeed and Altitude.

IIRC from the Metars, the weather was pretty decent up to and beyond 5,000 ft so they should have had good visual reference unless their heads were buried in the cockpit for some reason.
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salttee
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sat Jan 19, 2019 4:42 pm

FlyXLsa wrote:
Doesn't the Tower just read back the groundspeed and altitude from the ADS-B?

I thought they got it from their primary radar readout, but I don't know for sure; I got the idea from Brian Shul's ground speed check with Los Angeles Center.

https://theaviationgeekclub.com/sr-71-b ... eed-check/

I don't think an SR-71 uses ADS-B.
 
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PixelFlight
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sat Jan 19, 2019 4:48 pm

salttee wrote:
sgrow787 wrote:
I believe MCAS was designed to be using source selection on two redundant AOA sensors, and that somehow Boeing didn't do all the work - system design, software development, verification - to make it a realization.

That is an unhinged belief. You have no insight into what the MCAS designers wanted as far as AOA reliability; but we must assume that they knew how the rest of the 737 flight system was designed. The solution to a failing AOA sensor is to disable stab trim. It is not a problem without a solution.

I expect that the investigation on the MCAS safety assessment activity will be part of the report, to read if this problem analysis was done and if this "solution" was provided. It look like that neither the problem nor the solution was forwarded to the JT610 crew. Please note that never before the MAX, a 737 stab trim was depending on the AoA sensor (The STS do not depend on the AoA). On the fatal flight, the dependency of the stab trim on the AoA sensor was unknown to the crew, and there where no way for the crew to be alerted of AoA fault or to read the AoA incorrect value. Don't expect the crew to safely implement a not yet published solution about an unknown dependency and an undetectable problem.
 
salttee
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sat Jan 19, 2019 5:03 pm

PixelFlight wrote:
I expect that the investigation on the MCAS safety assessment activity will be part of the report, to read if this problem analysis was done and if this "solution" was provided. It look like that neither the problem nor the solution was forwarded to the JT610 crew. Please note that never before the MAX, a 737 stab trim was depending on the AoA sensor (The STS do not depend on the AoA). On the fatal flight, the dependency of the stab trim on the AoA sensor was unknown to the crew, and there where no way for the crew to be alerted of AoA fault or to read the AoA incorrect value. Don't expect the crew to safely implement a not yet published solution about an unknown dependency and an undetectable problem.

This just leads back to the hairsplitting debate of whether or not the event was runaway stab trim.

You as an engineer want to say that technically this was not a "runaway" stab trim because it was reset-able: (22 times). From a pilot's point of view, it was clearly runaway stab trim and a pilot is expected to know how to remove power to the stab trim motor. Removing power to an over eager stab trim system is essentially the same in all aircraft and not unique to the MAX.
 
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PixelFlight
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sat Jan 19, 2019 6:36 pm

salttee wrote:
PixelFlight wrote:
I expect that the investigation on the MCAS safety assessment activity will be part of the report, to read if this problem analysis was done and if this "solution" was provided. It look like that neither the problem nor the solution was forwarded to the JT610 crew. Please note that never before the MAX, a 737 stab trim was depending on the AoA sensor (The STS do not depend on the AoA). On the fatal flight, the dependency of the stab trim on the AoA sensor was unknown to the crew, and there where no way for the crew to be alerted of AoA fault or to read the AoA incorrect value. Don't expect the crew to safely implement a not yet published solution about an unknown dependency and an undetectable problem.

This just leads back to the hairsplitting debate of whether or not the event was runaway stab trim.

You as an engineer want to say that technically this was not a "runaway" stab trim because it was reset-able: (22 times). From a pilot's point of view, it was clearly runaway stab trim and a pilot is expected to know how to remove power to the stab trim motor. Removing power to an over eager stab trim system is essentially the same in all aircraft and not unique to the MAX.

Boeing requested urgent update to describes the MCAS dependency to AoA unsafe condition into the runaway stabilizer operating procedures to improve safety, because the lost of many lives obviously showed that it was unsafe. There is no debate about those facts. If you disagree with Boeing, please contact them. And this was not an engineer that was flying.
 
salttee
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sat Jan 19, 2019 8:06 pm

Boeing said all that?
 
2175301
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sat Jan 19, 2019 9:37 pm

salttee wrote:
Boeing said all that?


Obviously, to anyone who cannot actually read what they said without inputing their own interpretations and biases into what they did say.

By my readings and understandings of English (and regulatory speak) - I do not see that they said that. Alas, I do not apparently have the correct expertise to some to understand things...

Hope that helps clarify (or muddy the waters).

Have a great day,
 
sgrow787
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sat Jan 19, 2019 9:42 pm

salttee wrote:
sgrow787 wrote:
I believe MCAS was designed to be using source selection on two redundant AOA sensors, and that somehow Boeing didn't do all the work - system design, software development, verification - to make it a realization.

That is an unhinged belief. You have no insight into what the MCAS designers wanted as far as AOA reliability;


While I haven't ever worked on stall prevention systems, I have 15 yrs of commercial aerospace software engineering experience. None of the systems I've worked on didn't have some sort of source selection from multiple sensors. I doubt it's unhinged to think one of the most important systems on a plane is not using all the available sensors available to it.

No insight??
 
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PixelFlight
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sat Jan 19, 2019 9:50 pm

salttee wrote:
Boeing said all that?

The first part is a quick resume of the Boeing/FAA EAD 2018-23-51. Read it.

* About urgent and safety:
"Due to the need to correct an urgent safety of flight situation, good cause exists to make this AD effective in less than 30 days."

* About unsafe condition:
"This AD was prompted by analysis performed by the manufacturer showing that if an
erroneously high single angle of attack (AOA) sensor input is received by the flight control system,
there is a potential for repeated nose-down trim commands of the horizontal stabilizer. We are issuing
this AD to address this potential resulting nose-down trim, which could cause the flight crew to have
difficulty controlling the airplane, and lead to excessive nose-down attitude, significant altitude loss,
and possible impact with terrain.

* About MCAS:
"The 737-8/-9 uses a Flight Control Computer command of pitch
trim to improve longitudinal handling characteristics. In the event of
erroneous Angle of Attack (AOA) input, the pitch trim system can trim
the stabilizer nose down in increments lasting up to 10 seconds."

* About AFM Revision of the Operating Procedures:
"Within 3 days after receipt of this AD, revise the Operating Procedures chapter of the
applicable AFM to include the information in figure 2 to paragraph (h) of this AD."

You can debate the details of my quick resume wording, but be assured that I have no intention to voluntary distort the EAD importance.
 
N212R
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sat Jan 19, 2019 9:50 pm

Have there been any verifiable photos of this CVR since or during "recovery"?

In what percentage of accidents is a photo of the CVR released to the press or public? I seem to recall this as more common than not? Even more so given the long recovery effort and obvious interest in its contents.
 
salttee
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sat Jan 19, 2019 9:53 pm

sgrow787 wrote:
No insight??

Yes as I said, "You have no insight into what (those particular) MCAS designers wanted as far as AOA reliability."

You weren't there, you don't know. All you can do is post suppositions of what you think you would have considered if you were on that design team. Had you been there, the engineering dialogue and management direction might have led you to the same conclusions they arrived at.
 
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PixelFlight
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sat Jan 19, 2019 10:09 pm

salttee wrote:
sgrow787 wrote:
No insight??

Yes as I said, "You have no insight into what (those particular) MCAS designers wanted as far as AOA reliability."

You weren't there, you don't know. All you can do is post suppositions of what you think you would have considered if you were on that design team. Had you been there, the engineering dialogue and management direction might have led you to the same conclusions they arrived at.

Please respect professionals sharing real experience, in particular if you admit yourself that you have no insight in the fields there take time to describes.
Please read available description of recent design in aircraft avionic redundancy.
We all try to share the same facts, and we are all forced to make some suppositions to figure out some plausible scenarios. This is a collective and constructive process of thinking, nothing personal.
 
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FlyXLsa
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sat Jan 19, 2019 10:18 pm

salttee wrote:
Boeing said all that?


PixelFlight is simply quoting from the FAA Emergency Airworthiness Directive which he has done on numerous occasions for dramatic effect. One should not read anything into the strong warning language. The EAD was compiled by the FAA with the cooperation of Boeing.
We're NOT all going to die flying the Max!

Aviators FLY the plane. Flaps, Trim Tabs, Cutouts or Grab the "spinning wheel of fortune" and this accident doesn't happen.
It's called Airmanship.

FYI the EAD is here: https://theaircurrent.com/wp-content/up ... D-1107.pdf

If you want to read what BOEING sent out to operators it is as follows:

CATEGORY: Maintenance, Engineering, Flight Operations, Management, Safety

SERVICE REQUEST ID: 4-4298138108
ACCOUNT: Boeing Correspondence (MOM)
DUE DATE: No Action Required
PRODUCT NAME: Airplane
PRODUCT LINE: 737
PRODUCT: Several
ATA: 0000-57

SUBJECT: Information - Multi-Model Stall Warning and Pitch Augmentation Operation

REFERENCES: /A/ MOM-MOM-18-0655-018

A pitch augmentation system function called “Maneuvering Characteristics Augmentation System” (MCAS) is implemented on the 737-8, -9 (MAX) to enhance pitch characteristics with flaps UP and at elevated angles of attack. The MCAS function commands nose down stabilizer to enhance pitch characteristics during steep turns with elevated load factors in manual, flaps up flight. The system is designed to allow the flight crew to use the column trim switch or stabilizer aisle stand cutout switches to override MCAS input. The function is commanded by the the Flight Control Computer using input data from sensors and other airplane systems.

The MCAS function becomes active when the airplane AoA exceeds a threshold based on airspeed and attitude. Stabilizer incremental commands are limited to 2.5 degrees and are provided at a rate of 0.27 degrees per second. The magnitude of the stabilizer input is lower at high Mach numbers and greater at low Mach numbers. The function is reset once AoA falls below the AOA threshold or if manual stabilizer commands are provided by the flight crew. If the original elevated AoA condition persists, the MCAS function commands another incremental stabilizer nose down command according to the current aircraft Mach number at actuation.

The MCAS function is not incorporated on 737NG airplanes.
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salttee
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sat Jan 19, 2019 10:19 pm

PixelFlight wrote:
we are all forced to make some suppositions to figure out some plausible scenarios.

No, you are not forced to make suppositions about a process you didn't attend.
You can do that if you want to build a case to support your preconceived bias though.
 
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PixelFlight
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sat Jan 19, 2019 10:29 pm

salttee wrote:
PixelFlight wrote:
we are all forced to make some suppositions to figure out some plausible scenarios.

No, you are not forced to make suppositions about a process you didn't attend.
You can do that if you want to build a case to support your preconceived bias though.

You are right: you are also free to deny any information that you find yourself irrelevant and I respect your point of view. But you can't force anyone to deny anything.
 
Flaps
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sat Jan 19, 2019 10:53 pm

Having read all of the engineering theories above ad nauseum I have two things to say:

First - Thanks for all of the engineering insight on things that I do not need to know in order to fly an aircraft under normal or emergency conditions. It is useful to have this knowledge from a general systems standpoint. I'm never one to turn a away from an education on anything. Its all good stuff and I am better off for having read it all.

Second and most importantly - Not a damn bit of all that engineering insight and theory has any thing to do with my responsibilities as PIC or SIC when it comes to flying the plane. With the aircraft straight and level at cruise these insights and theories are valuable for trouble shooting a problem. They also have value when it comes to finding ways to make systems better and safer in the long term. Every accident has something to contribute in that area.
As pilots however, our first responsibility is to fly the plane. Let me repeat, our first responsibility is to fly the plane. It is beyond my comprehension as to why this crew failed to disable the electric trim. It is beyond my comprehension as to why when they were able to twice stabilize the aircraft by extending flaps why they did not leave it in that configuration and land the damn thing. Troubleshooting an unstable aircraft and repeating the same errors over and over at 5000 feet is a recipe for disaster. Flying the airplane and getting it back on the ground simply does not require all of the technical knowledge and analysis continuously repeated above. That stuff comes into play after the aircraft is safely on the ground.
There are reasons why this crew failed in the execution of their primary duties to fly the plane first. None of us know what those reasons were. It could be poor training, poor safety culture or many other things including issues that may have been beyond the crew's control. We just don't know yet. Fortunately the CVR has been found and fortunately it contains information from both the accident flight and the previous flight. In time we will have those answers. I'm not hanging this crew out to dry. That they failed to aviate is clear. What isn't clear is why, so it is premature to speculate or pass judgement at this point.

Lionair however continues to look worse and worse as more information becomes available. Max's aren't falling out of the sky and other operators don't seem to be having issues. The failure to properly assess the AoA issue, the dispatching of an aircraft that was clearly potentially unairworthy and the failure to communicate those issues to the accident crew are currently front and center as the probable causes. MCAS may have been a contributing factor as may be the AoA interface. In any case this accident has pointed out that there is potential to improve these systems. That's it. The root causes are Lionair's inability to correctly assess the trim issue, Lionair's decision to dispatch an aircraft in a potentially unairworthy state and the Lionair crews failure to aviate and failure to disable the electric trim. The issues are clear but are less important than the WHY behind them and the HOW to correct them going forward.

Flame Away
 
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FlyXLsa
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sat Jan 19, 2019 11:28 pm

Crashed Lion Air Jet’s recorder has two hours of cockpit voices
The National Transportation Safety Committee expects to finish transcribing 124 minutes of recording by Tuesday, Nurcahyo Utomo, the lead investigator at the agency, said by phone on Friday. The quality of the data from the final flight that lasted less than 15 minutes is good , he said.

Tuesday sounds pretty fast. Hopefully someone will leak some details!

https://www.hindustantimes.com/world-ne ... gcofP.html
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iamlucky13
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sun Jan 20, 2019 12:57 am

FlyXLsa wrote:
Tuesday sounds pretty fast. Hopefully someone will leak some details!


Hopefully not. Leaks are highly unlikely to aid the investigation and could be a distraction that hinders it, or inappropriately influences the expectations of policy makers who should be relying on information from the investigators themselves. This would be especially true if leaks whose authenticity can not be verified are given undue credibility.

So I rather say: hopefully investigators are ready to release information about the CVR contents quickly.
 
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scbriml
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sun Jan 20, 2019 4:44 am

N212R wrote:
Have there been any verifiable photos of this CVR since or during "recovery"?

In what percentage of accidents is a photo of the CVR released to the press or public? I seem to recall this as more common than not? Even more so given the long recovery effort and obvious interest in its contents.


You won’t see pictures of it as I t would be obvious it isn’t the real one. Make sure your theory is adjusted accordingly.
Time flies like an arrow. Fruit flies like a banana!
There are 10 types of people in the World - those that understand binary and those that don't.
 
sgrow787
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sun Jan 20, 2019 5:17 am

salttee wrote:
sgrow787 wrote:
No insight??

Yes as I said, "You have no insight into what (those particular) MCAS designers wanted as far as AOA reliability."

You weren't there, you don't know. All you can do is post suppositions of what you think you would have considered if you were on that design team. Had you been there, the engineering dialogue and management direction might have led you to the same conclusions they arrived at.


But I prefaced my statement by "I believe". I didn't put it forth as a statement of fact.

(Geez)
 
salttee
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sun Jan 20, 2019 6:20 am

sgrow787 wrote:
But I prefaced my statement by "I believe". I didn't put it forth as a statement of fact.
And I responded
saltee wrote:
That is an unhinged belief. You have no insight into what the MCAS designers wanted as far as AOA reliability
So you said:
sgrow787 wrote:
No insight??
With two question marks.

So I answered you with an explanation for why I claim you are unable to have insight into that Boeing design process:
saltee wrote:
Yes as I said, "You have no insight into what (those particular) MCAS designers wanted as far as AOA reliability."
You weren't there, you don't know. All you can do is post suppositions of what you think you would have considered if you were on that design team. Had you been there, the engineering dialogue and management direction might have led you to the same conclusions they arrived at.

Then PixelFlight jumped in and drug out this already much ado about nothing exchange further.

So now we are here. If you want to continue this discussion further we should probably do it by PM, as the conversation has nothing to do with finding the cause for the loss of JT610 and I'm sure that none of the other posters are interested in reading more of this conversation.
 
ryanov
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sun Jan 20, 2019 7:30 am

Flaps wrote:
Lionair however continues to look worse and worse as more information becomes available. Max's aren't falling out of the sky and other operators don't seem to be having issues.

To be fair, at present, neither is LionAir. This hasn't happened frequently at any airline.

Kudos on the rest of your post, BTW. Could use some more sense on here.
 
rheinwaldner
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sun Jan 20, 2019 9:27 am

fadecfault wrote:
Nice graph leaving out the runway trim on takeoff causing a nose dive. Of course that would not fit your narrative.

I did not leave out the MCAS action after take off. It is there in the diagram. Like the many MCAS actions in the second half of the flight, it was interupted two times using manual trim -> checklist completed, no runaway trim

fadecfault wrote:
fadecfault wrote:
3 If the runaway stops:
□□□□


I stand corrected the □□□□ means checklist completed. However from the QRH :
"The flight crew must be aware that checklists cannot be created for all conceivable
situations and are not intended to replace good judgment. In some situations, at the
captain’s discretion, deviation from a checklist may be needed."

Until page 40 or so of this thread Boeing's defence was: "the existing procedures cover MCAS failures". Now we found out, the existing procedure simply says "checklist completed" before ever reaching the stab trim cutout line item (because MCAS can be interrupted). So Boeing's defence is now "yes, the existing procedures dont cover MCAS failures, but we expect pilots to deviate from checklist to survive".

trpmb6 wrote:
As an engineer, I see the repetitive automatic Trim inputs and say that that is a runaway trim situation. Maybe after two times happening I wouldn't have thought so. But on the third time, I would have said to my self: What I'm doing is not correcting the overall situation.

You forget how manual trim is done. You do it not conscious. Imagine driving on a straight street. From time to time you make small corrections to keep track. Typically you would not be able to tell, in which direction you made the last few corrections. Likewise the pilots easily might miss the repetitive and systematic nature of the manual trim corrections, especially as they could not have assumed that the trim would be the source of their trouble.

ikramerica wrote:
As for this inane concepts of 20 repeated malfunctions in a short time is not “continuous”, that’s ludicrous.

It was not a so short time. It could have been enough, to miss that the events were in fact "linked" to the same problem. The pilots are trained according to the NNC. And this goes: if the trim stops -> checklist completed, there is no trim runaway. A trim runaway is not stoppable using the most common manual input device.

FlyXLsa wrote:
Read the NTSB documents on SW1380. The Captain there only loosely followed the 737 Checklist(s), and skipped a few, deviating several times from the prescribed procedures and settings for items such as "nearest airport", flaps and airspeed. I'll fly with HER any day, every day.

Same with US1549 on the way to the Hudson. They missed a few Checklist items including the "Ditch" setting for a water landing. Again... MY kind of AVIATORS. Fly first and follow the checklist later.

These examples are not the same. In these cases skipping a checklist item or even missing one was not so relevant and did no harm. But in case of a MCAS failure, deviating from the checklist was required to survive (otherwise the trim cutout step would never have been reached):
Non compliance with procedures having a minor, not dangerous impact - is not the same as - Compliance with procedures causing a full loss!!
Many things are difficult, all things are possible!
 
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FlyXLsa
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sun Jan 20, 2019 2:33 pm

rheinwaldner wrote:
These examples are not the same. In these cases skipping a checklist item or even missing one was not so relevant and did no harm. But in case of a MCAS failure, deviating from the checklist was required to survive (otherwise the trim cutout step would never have been reached):
Non compliance with procedures having a minor, not dangerous impact - is not the same as - Compliance with procedures causing a full loss!!


You completely missed the point of my statement and interjected your own thoughts.
I was responding to the following statement about FOLLOWING PROCEDURES/CHECKLISTS:

"2) a crew is trained to use procedures to solve problems and not randomly throw switches on a hunch"

PILOTS should NOT be automated robots simply ticking off items on a checklist.
They should use their BRAINS where applicable and first and foremost FLY THE PLANE.
Airmanship
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kalvado
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sun Jan 20, 2019 2:43 pm

FlyXLsa wrote:
rheinwaldner wrote:
These examples are not the same. In these cases skipping a checklist item or even missing one was not so relevant and did no harm. But in case of a MCAS failure, deviating from the checklist was required to survive (otherwise the trim cutout step would never have been reached):
Non compliance with procedures having a minor, not dangerous impact - is not the same as - Compliance with procedures causing a full loss!!


You completely missed the point of my statement and interjected your own thoughts.
I was responding to the following statement about FOLLOWING PROCEDURES/CHECKLISTS:

"2) a crew is trained to use procedures to solve problems and not randomly throw switches on a hunch"

PILOTS should NOT be automated robots simply ticking off items on a checklist.
They should use their BRAINS where applicable and first and foremost FLY THE PLANE.
Airmanship

It is hard to win this game. You can say they have to be creative - but experience says that the golden ages of heroic airmanship had crash rates tens of times higher than today. You can say pilots must get more stick time and less reliance on automation - but then mistakes become more common, and some of them end up bad..
I would say it is a conscious choice of the industry: more procedures, less improvisation, more workers, fewer heroes. Whether you like it or not.
 
fsabo
Posts: 197
Joined: Fri Dec 04, 2015 8:41 pm

Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sun Jan 20, 2019 2:56 pm

kalvado wrote:
FlyXLsa wrote:
rheinwaldner wrote:
These examples are not the same. In these cases skipping a checklist item or even missing one was not so relevant and did no harm. But in case of a MCAS failure, deviating from the checklist was required to survive (otherwise the trim cutout step would never have been reached):
Non compliance with procedures having a minor, not dangerous impact - is not the same as - Compliance with procedures causing a full loss!!


You completely missed the point of my statement and interjected your own thoughts.
I was responding to the following statement about FOLLOWING PROCEDURES/CHECKLISTS:

"2) a crew is trained to use procedures to solve problems and not randomly throw switches on a hunch"

PILOTS should NOT be automated robots simply ticking off items on a checklist.
They should use their BRAINS where applicable and first and foremost FLY THE PLANE.
Airmanship

It is hard to win this game. You can say they have to be creative - but experience says that the golden ages of heroic airmanship had crash rates tens of times higher than today. You can say pilots must get more stick time and less reliance on automation - but then mistakes become more common, and some of them end up bad..
I would say it is a conscious choice of the industry: more procedures, less improvisation, more workers, fewer heroes. Whether you like it or not.


I don't think that is correct. A computer is ideal for following a set of rules and proceedures blindly. Pilots are in the aircraft because the human brain can diverge from the rules and proceedures when necessary.

That said, if the situation were reversed and the aircraft crashed because the pilots diverged from proceedure (where following proceedure would not have resulted in a crash) then the pilots would again be at fault in the eyes of the boeing defenders. The pilots must take all the blame because boeing must take no blame.
 
oOfredOo
Posts: 32
Joined: Mon Oct 03, 2016 9:07 pm

Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sun Jan 20, 2019 3:00 pm

Five minutes of googling should put the no photo conspiracies to rest. From a newspaper:

https://www.jawapos.com/humaniora/15/01 ... -ditemukan

and from Av Herald:

http://avherald.com/h?article=4bf90724/0009&opt=0

Looks like the CVR to me.
 
User avatar
par13del
Posts: 8431
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sun Jan 20, 2019 3:14 pm

fsabo wrote:
The pilots must take all the blame because boeing must take no blame.

I would change that to say the OEM...millions of people fly on a regular basis, they must believe that the a/c they get on are safe, if anything happens it MUST be human and not machine.
 
StTim
Posts: 3293
Joined: Thu Aug 08, 2013 7:39 am

Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sun Jan 20, 2019 3:20 pm

par13del wrote:
fsabo wrote:
The pilots must take all the blame because boeing must take no blame.

I would change that to say the OEM...millions of people fly on a regular basis, they must believe that the a/c they get on are safe, if anything happens it MUST be human and not machine.


They must be sure the plane they are about to get on does not have a systematic fault which could kill them. I do not think anyone here is saying that it is just Boeings fault - but many seem to want to just point the finger at LionAir or the Pilots.

AAIB and NTSB accident reports, and I have read quite a few, rarely point a finger at a sole source.

I would have no issues getting on a MAX or any plane from Boeing\Airbus\Embraer etc. There was a point where I would have had concerns getting on a DC10.
Last edited by StTim on Sun Jan 20, 2019 3:32 pm, edited 1 time in total.
 
fsabo
Posts: 197
Joined: Fri Dec 04, 2015 8:41 pm

Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sun Jan 20, 2019 3:21 pm

par13del wrote:
fsabo wrote:
The pilots must take all the blame because boeing must take no blame.

I would change that to say the OEM...millions of people fly on a regular basis, they must believe that the a/c they get on are safe, if anything happens it MUST be human and not machine.


I said Boeing because it is in context of this particular thread. But you are correct; there are people who will defend their favored OEM regardless of the severity of the flaw in the machine.
 
User avatar
neutrino
Posts: 1536
Joined: Thu May 10, 2012 5:33 pm

Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sun Jan 20, 2019 3:27 pm

And there are those who would jump and point all digits including their toes at an OEM if the plane happens to be from not their favored manufacturer, so.....
Potestatem obscuri lateris nescitis
 
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FlyXLsa
Posts: 59
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sun Jan 20, 2019 3:31 pm

If we reduce flying to a series of checklists and button pushing, why even have human pilots in the cockpit? We could just use robots or AI to fly the plane. The reason we don't is (1) I wouldn't fly in it nor would most of the general public and (2) there are still situations that may arise that require an AVIATOR with FLYING SKILLS as I demonstrated in my prior post. There's no doubt procedures and checklist have made flying safer, but they are still no substitute for BASIC AIRMANSHIP.
Whiskey-Oscar-Oscar-Foxtrot
 
kalvado
Posts: 1715
Joined: Wed Mar 01, 2006 4:29 am

Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sun Jan 20, 2019 3:38 pm

fsabo wrote:
kalvado wrote:
FlyXLsa wrote:

You completely missed the point of my statement and interjected your own thoughts.
I was responding to the following statement about FOLLOWING PROCEDURES/CHECKLISTS:

"2) a crew is trained to use procedures to solve problems and not randomly throw switches on a hunch"

PILOTS should NOT be automated robots simply ticking off items on a checklist.
They should use their BRAINS where applicable and first and foremost FLY THE PLANE.
Airmanship

It is hard to win this game. You can say they have to be creative - but experience says that the golden ages of heroic airmanship had crash rates tens of times higher than today. You can say pilots must get more stick time and less reliance on automation - but then mistakes become more common, and some of them end up bad..
I would say it is a conscious choice of the industry: more procedures, less improvisation, more workers, fewer heroes. Whether you like it or not.


I don't think that is correct. A computer is ideal for following a set of rules and proceedures blindly. Pilots are in the aircraft because the human brain can diverge from the rules and proceedures when necessary.

That said, if the situation were reversed and the aircraft crashed because the pilots diverged from proceedure (where following proceedure would not have resulted in a crash) then the pilots would again be at fault in the eyes of the boeing defenders. The pilots must take all the blame because boeing must take no blame.

There are many layers in all this. I wonder how our perception would change once ATC switches from mumbling over the radio to computer-generated texts, for example.
Or the classic trolley problem, which became important with self driving cars...
But what was telling for me is a discussion on this site regarding a pretty interesting event (actually there were a few similar ones). I may be wrong on details, but the overall situation was like that:
a turboprop, dash-8 or ATR, was taking off from normal takeoff runway, YYZ or YOW. Runway long enough to handle long haul 777.
After rotation, the pilot got unhappy with plane controls, pulled back throttles, landed back, stopped and taxied to the gate. Overwhelming professional opinion was that stopping after rotation was a no-no. Even in this case. So, my strong impression is that crashing by following procedures seems an acceptable outcome for the industry, while surviving against procedures is questionable.
 
kalvado
Posts: 1715
Joined: Wed Mar 01, 2006 4:29 am

Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sun Jan 20, 2019 3:40 pm

FlyXLsa wrote:
If we reduce flying to a series of checklists and button pushing, why even have human pilots in the cockpit? We could just use robots or AI to fly the plane. The reason we don't is (1) I wouldn't fly in it nor would most of the general public and (2) there are still situations that may arise that require an AVIATOR with FLYING SKILLS as I demonstrated in my prior post. There's no doubt procedures and checklist have made flying safer, but they are still no substitute for BASIC AIRMANSHIP.

Pilots? to decode mumbling over radio, of course. And to take the blame if something happens.
Ideal 2-person cockpit: a pilot and a dog.
 
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FlyXLsa
Posts: 59
Joined: Thu Dec 27, 2018 5:03 pm

Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sun Jan 20, 2019 5:43 pm

StTim wrote:
I do not think anyone here is saying that it is just Boeings fault - but many seem to want to just point the finger at LionAir or the Pilots.


Boeing designed MCAS and did so making it dependent on a single source sensor without "fail safe" protection. No MCAS = No crash. As a number of us discussed previously they are going to be held to account legally. This thread is full of Boeing Bashers, Lion Air Flamers and others who are taking a more reasoned approach. Product liability was discussed a few pages back to which I will add the following quote:

"Strict product liability is a legal rule that says a seller, distributor or manufacturer of a defective product is
liable to a person injured by that product regardless of whether the defendant did everything possible
to make sure the defect never happened."


That being said, I've been pretty tough on Lion Air, their Maintenance and the failure of the Pilots to AVIATE. As you have stated, it is rare to see an accident with a single cause/failure source and this case is no exception. Lion Air is vicariously liable for the actions of their employees (in a US Court anyway) and is not going to escape blame for their negligence.

What remains to be seen is the percentage of fault attributed to each party -- comparative negligence.

"Comparative negligence states that when an accident occurs, the fault and or negligence of each party
involved is based upon their respective contributions to the accident."


If I was Boeing's defense counsel, I'd be feeling pretty good about this case since the release of the FDR. I'd love to pontificate in front of a jury about exactly how this plane crashed and what WAS NOT done to save it. My opening and closing statements would focus on the two cutout switches. The JT43 crew would be my first witnesses along with many other professional pilots that would testify MCAS inputs can be stopped in FOUR WAYS:

Trim Tab, Flaps, Cutout Switches or by Grabbing the Spinning Wheel!

I'll let you know if I use the CVR Transcript or if I make a motion to have it blocked once we know what's on the recording. I'd use the following black and white image of the switches for dramatic effect:

Image


So in summary, AT LEAST trav777 and I (plus many others) have said that Boeing is at fault with the caveat that Lion Air contributed as well.

trav777 also made a good post on the legalities of this case at #2467
Whiskey-Oscar-Oscar-Foxtrot
 
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SheikhDjibouti
Posts: 1697
Joined: Sat Sep 30, 2017 4:59 pm

Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sun Jan 20, 2019 6:48 pm

FlyXLsa wrote:
If we reduce flying to a series of checklists and button pushing, why even have human pilots in the cockpit? We could just use robots or AI to fly the plane. The reason we don't is (1) I wouldn't fly in it nor would most of the general public and (2) there are still situations that may arise that require an AVIATOR with FLYING SKILLS as I demonstrated in my prior post. There's no doubt procedures and checklist have made flying safer, but they are still no substitute for BASIC AIRMANSHIP.

The first time people got into an elevator without an elevator attendant, they probably were convinced they were going to die.

Now we have driverless trains, and the military are as usual leading the way with autonomous UAVs such as the MQ-9 Reaper.

Meanwhile, you are 100% correct of course. But I fear automatic pilots /unmanned aircraft are closer than any of us might imagine. And ironically, accidents such as Lion Air JT610 might provide the ammunition to bring it forward.
It will start with cargo flights, and move on through single-pilot operation, where the body in the cockpit is simply a machine minder, much like a certain well-known electric car/taxi operation. We won't have a clue because the pilot (or complete lack of one) will be conveniently hidden behind a locked cockpit door. Even the FAs will have to be kept in the dark.

Before too long we will be sold the idea of full automation, with carefully spun advertising.

"Global Airways is pleased to announce that from 1st April 2032, some of our flights (er, how many is that?) will feature Super-Safe© pilot technology.
This will ensure your flight will be safer and more comfortable than ever before (and we've got selected statistics to back that up).
As an added bonus, only available on Global Airways, if at any time during the flight you are concerned in any way, you may telephone our Help Desk (¹) and speak to a fully qualified pilot (50 hours on a Cessna 152) who will re-assure you that all is well.

Fly Global - the Automatic Choice

(¹) at busy times you can guarantee our Help Desk operators will be unavailable; normal network call charges apply
Nothing to see here; move along please.
 
sgrow787
Posts: 109
Joined: Fri May 16, 2014 8:12 pm

Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Sun Jan 20, 2019 11:21 pm

salttee wrote:
So now we are here. If you want to continue this discussion further we should probably do it by PM, as the conversation has nothing to do with finding the cause for the loss of JT610 and I'm sure that none of the other posters are interested in reading more of this conversation.


But you attacked my credibility. Maybe to hijack my thread. Granted I made a bold statement of view.

And, I think we all know what caused the JT610 crash, and that the current state of this discussion is about trying to prevent it and crashes like it from happening again.

To reiterate my view:

I believe MCAS was designed to use source selection on two redundant AOA sensors, based on my experience in aerospace software design - it doesn't make sense otherwise. I believe it is possible that something broke down in the development process that allowed a bug or design flaw to propagate to the delivered system. I'm mentioning this possibility because no one else is mentioning it since the discussion began.
 
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PixelFlight
Posts: 419
Joined: Thu Nov 08, 2018 11:09 pm

Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Mon Jan 21, 2019 7:18 am

sgrow787 wrote:
I believe MCAS was designed to use source selection on two redundant AOA sensors, based on my experience in aerospace software design - it doesn't make sense otherwise. I believe it is possible that something broke down in the development process that allowed a bug or design flaw to propagate to the delivered system. I'm mentioning this possibility because no one else is mentioning it since the discussion began.

I like the tread going more in that direction.

The technical information shared in this thread showed that the 737 design predate the deployment of aircraft ADIRU redundancy, as found in more recent design, and that the adaptation made in the various 737 iterations did keep the same *split sides" design. Implementing the MCAS function on the 737 FCC design require specific safety precautions because there is only a single AoA sensor / ADIRU available on the FCC data link. That's the technical facts.

I will not be surprised to learn that the redundancy of the AoA sensor / ADIRU was discussed inside Boeing when there designed the MCAS. We can speculate how this was eventually done and where the process eventually failed to ensure enough safety. From Boeing own communication, the process end up with a view that the MCAS is a small improvement, required by the new MAX flight characteristics, that did not deserve attention from the pilots. A journalist published the view of someone that declared that the MCAS was implemented lately because the problem was identified at the certification of the MAX. This could be the reason why the implementation was eventually done with a different process that it should be, with the result we know today.

Whenever that MCAS was done correctly or not, this aspect will certainly be analysed in the final report.
 
jsfr
Posts: 91
Joined: Tue Oct 20, 2009 2:36 am

Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Mon Jan 21, 2019 12:46 pm

I don't expect anything significant in the way of content, but after a week woudn't we normally know if the CVR is readable?

Not necessarily read - but I believe in past incidents (even 447) we had heard within a few days if the recorder was intact/damaged/unusable. etc.
 
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SheikhDjibouti
Posts: 1697
Joined: Sat Sep 30, 2017 4:59 pm

Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Mon Jan 21, 2019 1:22 pm

jsfr wrote:
I don't expect anything significant in the way of content, but after a week woudn't we normally know if the CVR is readable?

Not necessarily read - but I believe in past incidents (even 447) we had heard within a few days if the recorder was intact/damaged/unusable. etc.

Scroll back to yesterday; or click this link.
viewtopic.php?p=21027847#p21024091

FlyXLsa wrote:
Crashed Lion Air Jet’s recorder has two hours of cockpit voices
The National Transportation Safety Committee expects to finish transcribing 124 minutes of recording by Tuesday,

The quality of the data from the final flight that lasted less than 15 minutes is good , he said.

Tuesday sounds pretty fast.

Even faster than that for some; Jakarta is 15 hrs ahead of the US West Coast, so certain people in Seattle could be viewing these results on Monday night..... :D
Nothing to see here; move along please.
 
wingman
Posts: 3682
Joined: Thu May 27, 1999 4:25 am

Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Mon Jan 21, 2019 4:28 pm

FlyXLsa wrote:
I'll let you know if I use the CVR Transcript or if I make a motion to have it blocked once we know what's on the recording. I'd use the following black and white image of the switches for dramatic effect:


I think your post is exactly or very close to how this will play out in the US Court proceedings. But good luck getting the CVR dismissed. That'll never happen and will likely be the key piece of evidence that tilts the comparative negligence 60/40 or even 80/20 in either direction.
 
aljrooney
Posts: 21
Joined: Wed Jan 31, 2007 9:24 pm

Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Mon Jan 21, 2019 4:37 pm

My own humble thoughts on this and apologies if I have stated something erroneous or badly put.
For me, the issues really started while in the climb out.
MCAS is disabled with the flaps extended so the AoA issue would be masked until the crew went Flaps 0.
So is it possible that when the aircraft nose dropped after retraction that they assumed it was the IAS disagree from the previous flight? A bit of confirmation bias?
That they assumed the IAS was not showing the correct speed for flaps 0 retraction so put the flaps back to Flaps 1, (the last known good), trimmed up and increased thrust after the initial drop of a few hundred feet. Flying pitch and thrust
They then retracted flaps once more and this time with the increased thrust found just some nose trim was required to fly pitch and thrust and still thinking it was an IAS issue and with an eye on not overspeeding, never thinking another system (they allegedly knew nothing about) was misbehaving?
This would also explain the requests to the tower?
As the situation continued, there was a discussion that the Captain's IAS display was at fault (again maybe confirmation bias from what happened to the previous flight) and the CoPilot became PF. However he was less active on the trim, which let the MCAS increase the nose down trim to the point of no return?

I am not a pilot but have been reading all the excellent posts on here and just trying to go through the steps in my head without bringing the runaway trim NNC into it.
It just struck me that the supposed IAS disagree (whether real or not) seems to me more important than thought.
 
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PixelFlight
Posts: 419
Joined: Thu Nov 08, 2018 11:09 pm

Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Mon Jan 21, 2019 5:10 pm

aljrooney wrote:
MCAS is disabled with the flaps extended so the AoA issue would be masked until the crew went Flaps 0.
So is it possible that when the aircraft nose dropped after retraction that they assumed it was the IAS disagree from the previous flight? A bit of confirmation bias?
That they assumed the IAS was not showing the correct speed for flaps 0 retraction so put the flaps back to Flaps 1, (the last known good), trimmed up and increased thrust after the initial drop of a few hundred feet. Flying pitch and thrust

While it's established that the MCAS is disabled for flags others than 0. The FDR data from the preliminary report show that the AoA, IAS and ALT graphs all disagree between left and right at least immediately after takeoff, activating the left stick shaker, about a full minute before the flaps was retracted. Those disagreement are not influenced by the MCAS (but the MCAS act erratically if the AoA left sensor send a erratic high value).
 
fsabo
Posts: 197
Joined: Fri Dec 04, 2015 8:41 pm

Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Mon Jan 21, 2019 6:26 pm

PixelFlight wrote:
aljrooney wrote:
MCAS is disabled with the flaps extended so the AoA issue would be masked until the crew went Flaps 0.
So is it possible that when the aircraft nose dropped after retraction that they assumed it was the IAS disagree from the previous flight? A bit of confirmation bias?
That they assumed the IAS was not showing the correct speed for flaps 0 retraction so put the flaps back to Flaps 1, (the last known good), trimmed up and increased thrust after the initial drop of a few hundred feet. Flying pitch and thrust

While it's established that the MCAS is disabled for flags others than 0. The FDR data from the preliminary report show that the AoA, IAS and ALT graphs all disagree between left and right at least immediately after takeoff, activating the left stick shaker, about a full minute before the flaps was retracted. Those disagreement are not influenced by the MCAS (but the MCAS act erratically if the AoA left sensor send a erratic high value).


I think the aircraft should not have been flying. But that too a large degree is irrelevant. A perfectly maintained aircraft can have a single sensor failure at any point in the flight. This failure needs to be handled reasonably well by the hardware and software and not be too confusing to the crew. Here boeing fails.
 
luv2cattlecall
Posts: 803
Joined: Fri Sep 28, 2007 6:25 am

Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Mon Jan 21, 2019 7:11 pm

salttee wrote:
sgrow787 wrote:
If the sensors that help detect a stall or impending stall - ie AOA sensors - aren't working, then how can you pay attention to them? If you've got a stall prevention system - ie MCAS - that uses data from those sensors, _and_ it can't - whether a sw bug or a bad design - effectively choose the good sensor out of two available, .... what are you as a pilot suppose to do?

Fly pitch and power, disable stab trim, land asap.

sgrow787 wrote:
I believe MCAS was designed to be using source selection on two redundant AOA sensors, and that somehow Boeing didn't do all the work - system design, software development, verification - to make it a realization.



That is an unhinged belief. You have no insight into what the MCAS designers wanted as far as AOA reliability; but we must assume that they knew how the rest of the 737 flight system was designed. The solution to a failing AOA sensor is to disable stab trim. It is not a problem without a solution.


Could it have been certified if there was any intentional disengage of MCAS?
 
marcelh
Posts: 561
Joined: Wed Jun 19, 2013 12:43 pm

Re: Lion Air 737MAX8 Crashed Jakarta to Pangkal Pinang

Mon Jan 21, 2019 7:16 pm

aljrooney wrote:
My own humble thoughts on this and apologies if I have stated something erroneous or badly put.
For me, the issues really started while in the climb out.
MCAS is disabled with the flaps extended so the AoA issue would be masked until the crew went Flaps 0.
So is it possible that when the aircraft nose dropped after retraction that they assumed it was the IAS disagree from the previous flight? A bit of confirmation bias?
That they assumed the IAS was not showing the correct speed for flaps 0 retraction so put the flaps back to Flaps 1, (the last known good), trimmed up and increased thrust after the initial drop of a few hundred feet. Flying pitch and thrust
They then retracted flaps once more and this time with the increased thrust found just some nose trim was required to fly pitch and thrust and still thinking it was an IAS issue and with an eye on not overspeeding, never thinking another system (they allegedly knew nothing about) was misbehaving?
This would also explain the requests to the tower?
As the situation continued, there was a discussion that the Captain's IAS display was at fault (again maybe confirmation bias from what happened to the previous flight) and the CoPilot became PF. However he was less active on the trim, which let the MCAS increase the nose down trim to the point of no return?

I am not a pilot but have been reading all the excellent posts on here and just trying to go through the steps in my head without bringing the runaway trim NNC into it.
It just struck me that the supposed IAS disagree (whether real or not) seems to me more important than thought.


As an armchair pilot I have to say that you made an excellent factual analysis (IMHO).

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