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Ethiopian airliner down in Africa

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Ethiopian airliner down in Africa

Old 27th Apr 2019, 00:26
  #4381 (permalink)  
 
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Originally Posted by HundredPercentPlease View Post
Of course everyone here can do that. The ET crew could do that. Do you really think that an 8000 hour 737 captain didn't know how to do that?
There is no practical difference between a pilot who does not have certain skills and a pilot who cannot demonstrate those skills when needed.

You are missing the point - which is why they didn't do that. Or maybe why they couldn't do that. Or most importantly, why you may not do that as some point in the future.
Actually, this is exactly my point. I'm sure on nice sunny day with no distractions, or maybe with a jumpseater who could provide a third set of eyes, or perhaps during a pre-briefed sim session when they knew the malfunction was coming, either the Captain or First Officer could have parked the pitch at 10 degrees, set the power to 80% N1, trimmed the stab up to neutral no matter what spurious inputs the automation was making, and flown safely away from the ground. Unfortunately, in the real world we do not always have the luxury of being free from distractions, or having that jumpseater, or having our emergencies pre-briefed.

Why indeed could these crews not perform to the standards expected of a commercial pilot? Perhaps automation dependency and lack of hand-flying experience? Maybe an airline and training culture that emphasized rote procedures or systems management over basic airmanship skills? Sim training that was long on following scripts and checklists and short on big picture flying? First Officers that were light on experience and/or discouraged from speaking up when necessary? Perhaps some personal issues with the specific individuals? I could go on, but this would be a good start. I suspect the various accident boards will be looking at all these issues.

Yes, they could have and they should have but they didn't. That is why the human factor element of these accidents cannot and should not be ignored.

Last edited by 737 Driver; 27th Apr 2019 at 00:37.
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Old 27th Apr 2019, 00:44
  #4382 (permalink)  
 
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Originally Posted by Lost in Saigon View Post


The “problem” was explained in the Boeing Bulletin issued back in November 2018 after the Lion Air accident.

“Uncommanded nose down stabilizer trim due to erroneous Angle of Attack during Manual flight only”

Ethiopian airliner down in Africa
It is interesting that the revised runaway trim card in the official emergency AD is significantly different from the one in above, the note about using manual electrical trim was moved to the bottom and is not directly below the 'action' items. See page 7:

http://rgl.faa.gov/Regulatory_and_Gu...2018-23-51.pdf

Would a pilot converting to MAX in November have seen the Boing bulletin or just the revised per emergency AD manual?
Are the bulletins typically discarded when an official AD is issued?

Both of them talk of 'higher control forces may be needed' they do not specifically state that the manual trim might be unusable in a significantly mistrimed state.
Would be easy to read that as referring to column forces, especially by a someone not trained in the 'unloading'/ roller coaster maneuver

Last edited by MurphyWasRight; 27th Apr 2019 at 01:07. Reason: Added Comment on forces
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Old 27th Apr 2019, 01:03
  #4383 (permalink)  
 
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Originally Posted by MurphyWasRight View Post
It is interesting that the revised runaway trim card in the official emergency AD is significantly different from the one in above, the note about using manual electrical trim was moved to the bottom and is not directly below the 'action' items. See page 7:

http://rgl.faa.gov/Regulatory_and_Gu...2018-23-51.pdf

Would a pilot converting to MAX in November have seen the Boing bulletin or just the revised per emergency AD manual?
Are the bulletins typically discarded when an official AD is issued?
Also with the inclusion of "up to 10 seconds" clearly directed at MCAS - by MCAS not reference in either document.

Seems like a cover up - a non cover up would have given pilots more tools, like a L/H AoA failure can cause...............
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Old 27th Apr 2019, 01:21
  #4384 (permalink)  
 
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Originally Posted by MurphyWasRight View Post
Both of them talk of 'higher control forces may be needed' they do not specifically state that the manual trim might be unusable in a significantly mistrimed state.
I don't know for sure, but I think this statement might be a reference to activation of the Elevator Feel Shift Module (EFSM). This module is one of the 737 systems that may be activated by a stall signal from the Stall Management Yaw Damper (SMYD) computer. Activation is accompanied by annunciation of the FEEL DIFF PRESS light which is one of the symptoms mentioned in the AD.

Relevant quote from the 737 Aircraft Maintenance Manual (AMM)

EFSM Operation

At stall onset, either SMYD sends a signal to energize the dual coil solenoid valve on the EFSM. The EFSM operation occurs when all of these conditions occur:
• Stick shaker is active
• AOA is 8 to 11 degrees more than thermal anti-ice (TAI) biased stick shaker AOA
• EFSM is not inhibited due to low altitude or the airplane is on the ground.

When all of these conditions occur, the SMYDs energize the dual coil solenoid valve. The solenoid valve sends 3000 psi system A pressure to the pressure-operated mode valve. The mode valve opens and sends pressure between 820 psi to 880 psi from the pressure reducer to the system A side of the dual feel actuator. This increases the control column feel forces up to four times nominal feel. The increased feel force makes sure the pilots cannot easily override automatic stabilizer movement to nose down pitch of the airplane.
The FCOM has similar (though less detailed) information, though oddly it states the control forces only double.

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Old 27th Apr 2019, 02:37
  #4385 (permalink)  
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I've tried to look into the minds of the pilots in the latter part of this thread. I've even suggested that the ET PF's prior knowledge may have been counterproductive. The realisation that he is experiencing the same set of issues that were disastrous only months ago may have been truly alarming, countering any advantage he could have gained by having prior knowledge.

Suppose he was fixating on the attitude - he knows it's what he's supposed to do in this scenario. But he's also learned the autopilot could take the technical problem away and so frantically stabs at that a few times. Remember, things are very, very unreal to him at this time. Someone retorted that he didn't remember the flaps shouldn't be raised. Fair comment, but only recalling part of a briefing is not surprising at this moment.

So what's happening if he was focussing on the attitude? One thing's reasonably certain - he will* experience some tunnel vision. Not optical, but a kind of narrowed visual processing. Could it conceivably be enough to stop him seeing the wheel's white flashes? It seems impossible but how else is that protracted period of automatic spining explained? Is it the STS working harder, since the power is still high? I doubt he was that analytical with his hands full and being deluged with bad news.

*Being human is having more sub-processing going on that in the Boeing. We've all seen the spinning radar head change direction, despite knowing it hasn't. Or the Necker wire frame cube. We know that a sudden change happens, but what is incredible is that in most humans, it happens after a given number of seconds. That is very serious interference with our concious processing. Just an amusing bit of psychology, until you realise just how susceptible we are to our minds doing their own thing. A lot goes on that we can not escape from. Training around illusionary effects of acceleration and the products of fear is all we can do, and that's easier said than done.
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Last edited by Loose rivets; 27th Apr 2019 at 13:50. Reason: Cranking changed to Spining as former implies hand cranking
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Old 27th Apr 2019, 02:55
  #4386 (permalink)  
 
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via Flight Global

https://www.flightglobal.com/news/ar...-train-457736/

US pilots test Boeing’s new computer-based Max training


26 APRIL, 2019 SOURCE: FLIGHT DASHBOARD BY: JON HEMMERDINGER BOSTON

Boeing is sharing a proposed computer-based pilot training session with US pilot unions as part of its work to return the 737 Max to service, several sources familiar with Max’s re-certification efforts say.

The computer-based training session reviews the 737 Max’s speed trim system and the manoeuvring characteristics augmentation system (MCAS), which has been identified as among factors contributing to two 737 Max crashes.

Boeing has said it is developing new training, as well as updating the MCAS software, but the Chicago-based company has released few details.

Sources, who decline to be identified, now say Boeing has been sharing the computer training with pilots from unions representing cockpit crew at major US airlines.

The sources indicate that the airframer seeks to solicit feedback and objective input from pilots, and to ensure the aviation community’s involvement in efforts to return the Max to service.

Boeing’s proposed computer-based training can be completed on laptop or tablet computer, and takes as little as 15min, sources say.

The new speed trim training course comes in addition to existing computer training for pilots transitioning from the 737NG to the 737 Max. That existing course can be completed in less than 1h, according to one pilot.

Boeing did not immediately respond to a request for comment.

Some US pilots say 15min is enough to understand the speed trim system, noting their familiarity with the 737 Max. Other pilots have, more broadly, expressed frustration for receiving what they describe as minimal training when transitioning from the 737NG to 737 Max.

Three US airlines operated the 737 Max prior to the Federal Aviation Administration’s 13 March grounding: American Airlines, Southwest Airlines and United Airlines.

The three unions representing those company’s pilots decline to comment. The unions include the Southwest Airlines Pilots Association, the Allied Pilots Association, which represents American’s pilots, and the Air Line Pilots Association, which represents United’s cockpit crew.

The FAA will need to sign off on Boeing’s training and its software update, prior to lifting the 737 Max grounding, sources note.

What is still unclear is whether regulators might require training in addition to the computer-based sessions, such as time in a flight simulator.

However, on 25 April, Southwest Airlines chief executive Gary Kelly cast doubt on the possibility of additional simulator training. “We are not hearing that will be a requirement," he said. “Managing the aircraft in a runaway stabiliser scenario is something that we've already covered.”

The day before, Boeing chief executive Dennis Muilenburg said the company had completed 135 test flights with the MCAS update, equating to more than 230h of flight-test time. The airframer has said it completed flight tests of the software update on 17 April.

Last week, an FAA panel released updated pilot training standards that now call for pilots to receive ground training that addresses MCAS “system description, functionality, associated failure conditions and flight crew alerting”.

“These items must be included in initial, upgrade, transition, differences and recurrent training,” the updated report said.

Boeing introduced the speed trim system on the 737NG, then added MCAS to the Max. MCAS ensures the types operate similarly by pushing the Max’s nose down if the system senses it is too high.

MCAS activated prior to the October 2018 crash of a Lion Air 737 Max 8 and the March crash of an Ethiopian Airlines aircraft of the same type. It apparently activated following input of faulty angle-of-attack data, investigators have said.

Boeing’s Muilenburg has taken responsibility for updating MCAS, though the crashes have spurred discussion about pilot training and questions about what role pilots may have played in the crashes.

Both investigations are ongoing.
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Old 27th Apr 2019, 03:36
  #4387 (permalink)  
 
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Pretty interesting video about pilot decision making.

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Old 27th Apr 2019, 04:03
  #4388 (permalink)  
 
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Boeing’s proposed computer-based training can be completed on laptop or tablet computer, and takes as little as 15min, sources say
Well that sounds like thorough and comprehensive training to me! Seriously, four hundred people died, it was the pilot's fault entirely, and this is their solution?

Last edited by Water pilot; 27th Apr 2019 at 04:32.
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Old 27th Apr 2019, 04:21
  #4389 (permalink)  
 
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Originally Posted by Winemaker View Post
Pretty interesting video about pilot decision making.
Interesting indeed. Covered in a thread on this forum last year: Miss Velma's engine failure and crash landing at Duxford from the cockpit
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Old 27th Apr 2019, 04:27
  #4390 (permalink)  
 
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Originally Posted by Water pilot View Post
Well that sounds like thorough and comprehensive training to me! Seriously, four hundred people died, it was the pilot's fault entirely, and this is their solution?
Water pilot, you do understand it is in addition to the differences training that can be done in under an hour on the iPad!

I hope the rest of the world regulators fight for correct training levels - what ever that maybe, but I doubt 15 mins cuts it!
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Old 27th Apr 2019, 04:29
  #4391 (permalink)  
 
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Originally Posted by Water pilot View Post
Well that sounds like thorough and comprehensive training to me! Seriously, four hundred people died, it was the pilot's fault entirely, and this is their solution?
15 minutes training? No offense to all the professionals on this forum, but I will not get close to any MAX, an unstable airframe will be fixed by a software patch, and such will require 15 min training? When certifications were written there was bot software patch, airframes havd to complay by DESIGN
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Old 27th Apr 2019, 04:29
  #4392 (permalink)  
 
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Originally Posted by Water pilot View Post
Well that sounds like thorough and comprehensive training to me! Seriously, four hundred people died, it was the pilot's fault entirely, and this is their solution?
How many hours/days/weeks/years of training do you suggest is appropriate to reinforce/retrain that one needs to use normal trim to re-trim to an appropriate speed and then use the pitch trim disconnect switches in the event of an MCAS or runaway trim event?
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Old 27th Apr 2019, 04:37
  #4393 (permalink)  
 
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Objectively, seven pilots from various countries failed to recognize the "obvious" fact that they had runaway trim. A whole bunch of people died as a result. If this is a training issue, I want however much training is required to correct this deficiency.
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Old 27th Apr 2019, 04:40
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Originally Posted by formulaben View Post
How many hours/days/weeks/years of training do you suggest is appropriate to reinforce/retrain that one needs to use normal trim to re-trim to an appropriate speed and then use the pitch trim disconnect switches in the event of an MCAS or runaway trim event?
When you kill that MCAS or it has it's once limited "correction" - you are flying an aircraft that can no longer meet the certification requirements that it is approved for!

So say again - it no longer can meet certification requirements in certain flight modes/areas.

So how often do you fly outside certification limits? and how much training did you receive to do that? and was it on an Ipad?

This is not retaining - you have never flown in un-certifiable condition before on a 737 where MACS is required but not available.

Note this has nothing to do with a MCAS run away or trim run away - this is in normal flight when MCAS has been shut down (a number of events can now do this) or had one input and can not now, put in a second input to keep in certification limits..
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Old 27th Apr 2019, 04:48
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Originally Posted by Bend alot View Post
When you kill that MCAS or it has it's once limited "correction" - you are flying an aircraft that can no longer meet the certification requirements that it is approved for!

So say again - it no longer can meet certification requirements in certain flight modes/areas.

So how often do you fly outside certification limits? and how much training did you receive to do that? and was it on an Ipad?

This is not retaining - you have never flown in un-certifiable condition before on a 737 where MACS is required but not available.

Note this has nothing to do with a MCAS run away or trim run away - this is in normal flight when MCAS has been shut down (a number of events can now do this) or had one input and can not now, put in a second input to keep in certification limits..
Sorry, I can't interpret your answer. Perhaps you must have misinterpreted my question, so I'll ask it again and this time I'll go slowly and use different words: you seem upset with the re-training procedure; so I will ask again what quantity of training do you suggest is appropriate to reinforce/retrain that one needs to use normal trim to re-trim to an appropriate speed and then use the pitch trim disconnect switches in the event of an MCAS or runaway trim event? What amount of training is appropriate for any other event?
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Old 27th Apr 2019, 05:01
  #4396 (permalink)  
 
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Originally Posted by formulaben View Post
Sorry, I can't interpret your answer. Perhaps you must have misinterpreted my question, so I'll ask it again and this time I'll go slowly and use different words: you seem upset with the re-training procedure; so I will ask again what quantity of training do you suggest is appropriate to reinforce/retrain that one needs to use normal trim to re-trim to an appropriate speed and then use the pitch trim disconnect switches in the event of an MCAS or runaway trim event? What amount of training is appropriate for any other event?
You do understand MCAS is a requirement for flight within certification requirements?

With MCAS disabled (due now to any of a number of reasons) - how is flight within certification requirement limits meet?

Nothing at all to do with any trim event (Important you understand that) but what is flight like outside the certifiable limits?

I will agree there is NO REQUIREMENT for a trim run away - extra training, it is pointless



I do believe that training is required if the aircraft has probable possibility to be flown outside certification limits, but within the approved flight envelope of the aircraft.

Training required is not known by most of us, but only those that have flow MCAS during it's testing. It is reasonable to believe that the difference with MCAS and without MCAS is pretty large, as design used 0.6 degrees as the input but in flight tests 2.5 was required to get the correct feel.
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Old 27th Apr 2019, 05:02
  #4397 (permalink)  
 
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Just getting caught up after a long day of family stuff.

First I want to thank the individuals who had kind words, or otherwise expressed positive thoughts about my post from last night. After putting it out there I was torn, worried that I had made a mistake- I now see I did not.

Second- 737 Driver and others bring up really valid points and if/where we see things differently it isn't in the idea that the system failed completely. I would argue that putting a kid with less than 300 hours in the right seat of any transport category aircraft is near malpractice, and should said aircraft hit the ground in an uncontrolled dive blaming that kid is not only unfair, it is downright obscene. When I shared what I did last night it wasn't to expiate the guilt of the crews, but instead to try and get people to realize that "blaming" people who are no longer here to defend themselves is a bit disingenuous, and equally it distracts us from the very real root causes of the two incidents.

There is one huge difference between my position and that expressed most recently by 737 Driver, and that is to the responsibility for the outcome of what happened. Note that I say responsibility and not blame. After reviewing the technical and other data in great detail I am confident that responsibility lies solely with one party, as aided and abetted by another. Once the dominoes had been lined up the outcome was basically assured as it was only a matter of time.

Specifically: Boeing designed and placed into service an airplane with an active control system that had unilateral control over the horizontal stabilizer, with enough authority to place the airplane in an unrecoverable state if just a single component failed. Further this system gave no indication to the pilots that it was operating, or when malfunctioning that it was operating in error. Additionally this system, which was created solely to increase the amount of force required to pitch up the aircraft at high AOA used the most critical part of the airframe to do this minimal task, instead of using a passive system that had no control authority.

The result of this sad effort was a system that, if it failed, would basically try to kill the pilot and everyone on board. I say again: MCAS will try to kill everyone on board if it fails.

I simply cannot recall (but am inviting others here to fill in the blanks if you can) another system on a transport category aircraft with a failure mode that defaulted to "I'm going to try to fly the airplane into the ground. If you line up all the dots and pull two switches at the right moment I will let you live. Otherwise you die... Oh, and BTW I'm also going to fail concurrently with three or four other systems, which actually will alert you to their issues, unlike me, who will sit here quietly winding your trim forward until you get to the point where you cannot wind it back. Sorry about that!!" (It's also worth noting here that the Emergency AD that was put out only gave instruction on what was essentially an enhanced trim runaway. There is no actual way (that I have seen) for a pilot to actually determine if MCAS is malfunctioning. At best you are to stop the resultant (trim runaway) and remain in ignorance over the state of MCAS. WTF?? A system with complete authority over the horizontal stab and you have no way of knowing anything about it. Failure modes, operational status, errors, nothing. Just "If the airplane is trimming down (for whatever reason) and you don't want it to pull the console switches." Really??)

These incidents, indeed the entirety of MCAS' existence are a failure of corporate responsibility aided and abetted by a complete abrogation of regulatory responsibility. All in the pursuit of profits for shareholders.

We can blame the previous Lion Air Crew and maintenance for a lot. We can find fault with the performance of the crews, and we will. But in the end, the only entity who both could have designed a safe airplane, and who not only failed but by all appearances worked to conceal their failure through omission, was Boeing. And the agency that looked the other way was the FAA.

Those are the responsible parties, and that is what I hope people will look carefully at. It starts with the airplane. Build a safe one and operators will still find a way to muck things up, and crews will still make mistakes. But step one, the most important step, is build an effing safe airplane.

Warm regards,
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Old 27th Apr 2019, 05:14
  #4398 (permalink)  
 
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Originally Posted by Bend alot View Post
When you kill that MCAS or it has it's once limited "correction" - you are flying an aircraft that can no longer meet the certification requirements that it is approved for!

So say again - it no longer can meet certification requirements in certain flight modes/areas.

So how often do you fly outside certification limits? and how much training did you receive to do that? and was it on an Ipad?

This is not retaining - you have never flown in un-certifiable condition before on a 737 where MACS is required but not available.

Note this has nothing to do with a MCAS run away or trim run away - this is in normal flight when MCAS has been shut down (a number of events can now do this) or had one input and can not now, put in a second input to keep in certification limits..
I agree with most of your concerns, and have made similar comments myself. The revised MCAS details are still not clear, but there are two "escape" causes that could bypass your argument:
- The first is that MCAS may not be imited to one activation per flight, but can do so again, if a specific set of conditions permit. For example, nose-down trim unwinding, or AOA remaining below the threshold, together with no pilot control inputs for 15 continuous seconds.
- The second is that AOA disagree could be treated as a MEL equipment failure, and mandate landing at the nearest avaliable airport. I have not seen any reference to this, so the implication may be that MCAS is not flight critical, but rather a paper certification issue for a rarely encountered flight condition.

Whether the Joint Authorities Technical Review buy either of these arguments remains to be seen.

Edit: My comment was drafted while other replies to the same point were posted.
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Old 27th Apr 2019, 05:38
  #4399 (permalink)  
 
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Originally Posted by GordonR_Cape View Post
I agree with most of your concerns, and have made similar comments myself. The revised MCAS details are still not clear, but there are two "escape" causes that could bypass your argument:
- The first is that MCAS may not be imited to one activation per flight, but can do so again, if a specific set of conditions permit. For example, nose-down trim unwinding, or AOA remaining below the threshold, together with no pilot control inputs for 15 continuous seconds.
- The second is that AOA disagree could be treated as a MEL equipment failure, and mandate landing at the nearest avaliable airport. I have not seen any reference to this, so the implication may be that MCAS is not flight critical, but rather a paper certification issue for a rarely encountered flight condition.

Whether the Joint Authorities Technical Review buy either of these arguments remains to be seen.

Edit: My comment was drafted while other replies to the same point were posted.
Yes details are low!

The fact you actually understand MCAS conditions are not limited to a "run away trim" and actually MCAS is required to meet certification requirements during manual flight and this may require training (hands on), is good to know - seems many do not understand.
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Old 27th Apr 2019, 06:11
  #4400 (permalink)  
 
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Rumors concerning whistleblower reports about the AoA sensor are emerging.

"One whistleblower reported to the FAA that they had seen damage to the electrical wiring connected to the plane’s angle of attack sensor from a foreign object, which feeds data to the MCAS system so it can determine whether it needs to engage to prevent the plane from stalling. "

https://interestingengineering.com/b...roblems-to-faa
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