Go Back  PPRuNe Forums > Flight Deck Forums > Rumours & News
Reload this Page >

Ethiopian airliner down in Africa

Rumours & News Reporting Points that may affect our jobs or lives as professional pilots. Also, items that may be of interest to professional pilots.

Ethiopian airliner down in Africa

Old 7th May 2019, 02:16
  #5061 (permalink)  
 
Join Date: May 2010
Location: Boston
Age: 68
Posts: 410
737 Driver
I see the wisdom in much of your post, one thing to keep in mind though is that we have glaringly incomplete CVR facts, not a transcript just some snips possibly selected to shore up a particular point of view.
This makes it impossible to know all of what was discussed etc during (and before) the flight or the full extent of interactions.

As I have said before something was going on while the trim was in cutout mode, we just have not been told what.
MurphyWasRight is offline  
Old 7th May 2019, 02:31
  #5062 (permalink)  
 
Join Date: Apr 2019
Location: USA
Posts: 217
Originally Posted by MurphyWasRight View Post
737 Driver
I see the wisdom in much of your post, one thing to keep in mind though is that we have glaringly incomplete CVR facts, not a transcript just some snips possibly selected to shore up a particular point of view.
This makes it impossible to know all of what was discussed etc during (and before) the flight or the full extent of interactions.

As I have said before something was going on while the trim was in cutout mode, we just have not been told what.
I agree it is an incomplete picture (which I did acknowledge), but there are some broad enough outlines from which we can draw some conclusions. If anything comes out that substantially alters our current understanding, then I'll be happy to make a correction.

As far as what was going on while the the trim switches were in the cutout position, are you referring to the gradual movement from 2.3 to 2.1 units? It apparently occurred over two and half minutes. I'm interested in seeing what the board's thoughts are on that as well, but I should point out that in the context of the overall trim movement, it is a very small and slow creep.
737 Driver is offline  
Old 7th May 2019, 03:25
  #5063 (permalink)  
 
Join Date: Apr 2010
Location: transient
Age: 71
Posts: 16
737 Driver
"the possible existence of a steep authority gradient on the flight deck as potential threats."

Cue to possible existence of a steep authority gradient on a flight deck by employing metrics used to evaluate and judge Korean Air and third world cockpits.

Cactus fifteen fifty minus one, UsAir flight 1539 revisited.

15:29:45.4 hot-1 ok lets go put the flaps out, put the flaps out. ( this is not a proper command)
15:29:48 hot-2 flaps out? (Skiles not sure about what his captain wants him to do, Sully silent.)
15:30:01 hot-2 got flaps out.

15:30:06 cam-2 hundred and seventy knots.
15:30:09 cam-2 got no power on either one? try the other one.
15:30:16 hot-2 hundred and fifty knots.
15:30:17 hot-2 got flaps two, you want more? (Skiles somehow sensed that Sully wants to stay airborne so he gave him best glide flaps.)

Mitigated Speech and Plane Crashes (Outliers, p 195)

1- Command: “Turn thirty degrees right.” That’s the most direct and explicit way of making a point imaginable. It’s zero mitigation.
2- Crew Obligation Statement: “I think we need to deviate right about now.”Notice the use of “we” and the fact that hte request is now much less specific. It’s a little softer.
3- Crew Suggestion: “Let’s go around the weather.” Implicit in that statement is “we’re in this together.”
4- Query: “Which direction would you like to deviate?” That’s even softer than a crew suggestion, because the speaker is conceding that he’s not in charge.
5- Preference: “I think it would be wise to turn left or right.”
6- Hint: “That return at twenty-five miles looks mean.” This is the most mitigated statement of all.

In that scale above ” you want more?” is a “querry” in line 4 and a “hint” ( you should have more ) in line 6. Both indicative of mitigating speech is employed. By mitigating speech being employed we deduce that there is a strong authority gradient in the cockpit.

Last edited by wetbehindear; 7th May 2019 at 03:42.
wetbehindear is offline  
Old 7th May 2019, 05:44
  #5064 (permalink)  
 
Join Date: Dec 2013
Location: Dallas
Posts: 94
Originally Posted by wonkazoo View Post
Imagine if your airplane had a third, previously unneeded engine that contributed nothing to the performance, stability, safety or functionality of the aircraft. I'm even going to give us the benefit of the doubt and say you know this third engine exists. If engines 1 or 2 fail you just do everything like you always have. Pull out the proper checklist, do your memory items and find someplace to land. But if engine #3 fails, well then you have 30 seconds to a minute to identify the correct engine, diagnose it and shut it down using an exact mechanism that has zero tolerance for deviation. If you fail to do this exactly right your third engine explodes and rips off the tail in the process and you and your airplane are toast on a stick.

That's what I mean when I say MCAS will try to kill you (it will...) and that's why I believe this is a unique circumstance and finally: That's why I place the responsibility for the entirety of the outcome for both flights at the feet of Boeing and the FAA.
The repetitive hyperbole in your posts masks any real content for discussion that may exist.

The above quoted strawman is not an accurate allegory for the actual events which occur when the MCAS system is activated. It does not demand "zero tolerance for deviation", nor does it require "using an exact mechanism" to diagnose what is essentially a runaway stabilizer trim event.

Mitigation does require correct diagnosis and reaction. The actions of the ET 302 crew were sadly deficient in both regards. Discussion of their response and examination of aircrew training and competency overall is of more interest to me than your insistent claims of nefarious negligence by Boeing and the FAA.


ThreeThreeMike is offline  
Old 7th May 2019, 06:19
  #5065 (permalink)  
Thread Starter
 
Join Date: Feb 2008
Location: DORSET
Age: 62
Posts: 42
Any MAX pilots here?

Are there any contributors here who are 737 pilots who transitioned to the MAX?

May I ask please,
If you did, did you have any SIM, classroom, or Line training on the MAX and it's differences, or was it purely on-line modules, thus was your first flight on a ''pax on board'' flight?

Were you made fully aware of the adverse pitch up changes, and CG issues of the new MAX due to the design enforced forward location of the new larger engines (which can now cause lift) at low weights/high power applications resulting in a (unrecoverable?) high AOA? (which we now are aware, necessitated the MCAS software patch)

Were you (before the 2 fatal and 1 nearly accidents) fully informed/trained on the new MCAS systems and it's functionality, implications, and what to do if it went rogue?

Thanks.
rog747 is offline  
Old 7th May 2019, 06:38
  #5066 (permalink)  
 
Join Date: Jun 2003
Location: UK
Posts: 2,181
Rog,

No one knew about MCAS until the AD a couple of weeks after the Lion Air accident. Have a look at the thread. The crew that saved the situation described the problem as the STS running the wrong way, possibly a huge clue as to how the human mind interpreted what was happening (rather than a trim runaway).

All operators used CBT rather than real training.
HundredPercentPlease is offline  
Old 7th May 2019, 06:48
  #5067 (permalink)  
Thread Starter
 
Join Date: Feb 2008
Location: DORSET
Age: 62
Posts: 42
Originally Posted by HundredPercentPlease View Post
Rog,

No one knew about MCAS until the AD a couple of weeks after the Lion Air accident. Have a look at the thread. The crew that saved the situation described the problem as the STS running the wrong way, possibly a huge clue as to how the human mind interpreted what was happening (rather than a trim runaway).

All operators used CBT rather than real training.
OK thanks -
so what you are saying would also confirm that no pilots (putting aside MCAS as you say) were ever made aware of the adverse pitch up effect of the new MAX due to the location of the larger engines (which can now cause lift) at low weights/high power applications resulting in a (unrecoverable?) high AOA?
rog747 is offline  
Old 7th May 2019, 06:51
  #5068 (permalink)  
 
Join Date: Dec 2015
Location: Cape Town, ZA
Age: 57
Posts: 378
Originally Posted by rog747 View Post
OK thanks -
so what you are saying would also confirm that no pilots (putting aside MCAS as you say) were ever made aware of the adverse pitch up effect of the new MAX due to the location of the larger engines (which can now cause lift) at low weights/high power applications resulting in a (unrecoverable?) high AOA?
Its buried in the thread, but if you want an up to date reference, the 60 Minutes documentary (video and text) provides some interviews. For example Dennis Tajer (APA union). See: https://www.9news.com.au/national/60...6-a0c47ddfe293
Days after the Lion Air disaster, Boeing finally revealed the existence of the MCAS system, shocking pilots around the world.

American Airlines veteran pilot Dennis Tajer told Hayes, “I called our safety experts and said, ‘Where is this in a book?" And they said, ‘It's not’.”

Tajer said the admission from Boeing felt like “betrayal”.“This is an unforgiving profession that counts very heavily on the pilot's knowledge, background, and training, and there are lives depending on that."

Last edited by GordonR_Cape; 7th May 2019 at 06:52. Reason: Change quoted text.
GordonR_Cape is online now  
Old 7th May 2019, 08:46
  #5069 (permalink)  
 
Join Date: Jun 2003
Location: UK
Posts: 2,181
Originally Posted by rog747 View Post
OK thanks -
so what you are saying would also confirm that no pilots (putting aside MCAS as you say) were ever made aware of the adverse pitch up effect of the new MAX due to the location of the larger engines (which can now cause lift) at low weights/high power applications resulting in a (unrecoverable?) high AOA?
Rog - you don't have that quite right. It's high AoA that results in different stick forces. In normal operations the pilot would not ever create an AoA that would allow him to explore the new stick forces. Boeing logic was that if the pilot inadvertently found himself in such a high AoA condition, then all would feel normal because MCAS would trigger. Boeing just failed to explore what would happen if the single input to MCAS failed causing it to repeatedly trigger when not wanted.
HundredPercentPlease is offline  
Old 7th May 2019, 09:01
  #5070 (permalink)  
 
Join Date: Nov 2010
Location: Atlanta
Age: 51
Posts: 408
Originally Posted by rog747 View Post
Are there any contributors here who are 737 pilots who transitioned to the MAX?

May I ask please,
If you did, did you have any SIM, classroom, or Line training on the MAX and it's differences, or was it purely on-line modules, thus was your first flight on a ''pax on board'' flight?

Were you made fully aware of the adverse pitch up changes, and CG issues of the new MAX due to the design enforced forward location of the new larger engines (which can now cause lift) at low weights/high power applications resulting in a (unrecoverable?) high AOA? (which we now are aware, necessitated the MCAS software patch)

Were you (before the 2 fatal and 1 nearly accidents) fully informed/trained on the new MCAS systems and it's functionality, implications, and what to do if it went rogue?

Thanks.
Not to derail the tread, but this is the standard today. I am only trained in the A 320 CEO, but fly A319/320/321/320NEO (which has different engine instrument). We just received a company memo (after over a year of flying the NEO) that is has a “Rotation Mode” to prevent tail strike. Nothing was mentioned in the manual.........
hans brinker is offline  
Old 7th May 2019, 09:21
  #5071 (permalink)  
 
Join Date: Jun 2002
Location: Scotland
Posts: 32
Originally Posted by HundredPercentPlease View Post
Rog - you don't have that quite right. It's high AoA that results in different stick forces. In normal operations the pilot would not ever create an AoA that would allow him to explore the new stick forces. Boeing logic was that if the pilot inadvertently found himself in such a high AoA condition, then all would feel normal because MCAS would trigger. Boeing just failed to explore what would happen if the single input to MCAS failed causing it to repeatedly trigger when not wanted.
Apart from this lack of 'fail safe', add the failure to inform pilots of MCAS having been fitted, to install an 'MCAS on' warning and to signal the need for appropriate training including how to disable MCAS if required. Did Boeing also not fail to advise the FAA of a change in the scale or parameters of MCAS*?

*Ref Schmerik above : "There's the change of the rate of trim applied made late in the testing stages (from 0.6 units to 2.5 units per time period?)"

Last edited by dufc; 7th May 2019 at 10:04.
dufc is offline  
Old 7th May 2019, 09:44
  #5072 (permalink)  
 
Join Date: Mar 2018
Location: Central UK
Posts: 283
The crew that saved the situation described the problem as the STS running the wrong way, possibly a huge clue as to how the human mind interpreted what was happening (rather than a trim runaway).
Which rather vindicates Boeing's position on this; they reacted exactly as Boeing intended by identifying it as an STS runaway (which most assuredly is a runaway trim event) and dealt with it by using the correct pre-existing technique.

And as such, why is it really so necessary to inform pilots of this system? There is no specific control over it, just the generic runaway trim procedure. Surely telling people about systems they have no specific influence over is merely muddying the waters? If it presents itself as failure event X which is dealt with by checklist Y does anyone need to know that it could be system A or A.1 at fault, when both are addressed by the same checklist, show effectively the same symptoms and actually are components of the same system?

That, I am sure, was Boeing's rationale and though I'm not 100% comfortable with it I'm certainly not condemning it in the absolute and fundamental way some others are.

Boeing just failed to explore what would happen if the single input to MCAS failed causing it to repeatedly trigger when not wanted.
I very much doubt that could be the case. Single input failures would be top of the list to explore if the system only had one input. I think suggesting otherwise is being far too simplistic in automatically assuming gross incompetence where there really is no evidence of it. I read somewhere they spent 205 hours test-flying MCAS. What do you suppose they were looking at in all that time? That single-input failures hadn't occurred to anyone? No one at all? That is simply preposterous.

Boeing's big 'mistake' was to underestimate the public and to some extent the industry's interpretation of two failures due almost exclusively to bad handling and incorrect procedures that they could hardly have anticipated. At least, Boeing thought they could hardly have been anticipated at the time, and I doubt (m)any of us would have thought otherwise either before these accidents had we known about the system. Their mistake was to underestimate the amount and volume of criticism that would unexpectedly come their way because crews, maintenance and at least one airline screwed up in spades and the world retrospectively devined faults therefrom in Boeing that no one had thought were faults before and in a vindictive and vitriolic way unprecedented in the history of aviation.
Caught out by the 'told you so' all-seeing retrospective 'wisdom' of the internet more than anyting else.

I'm not saying they're whiter than white, just some light-ish shade grey a very long way from the midnight black some others are portraying.

We just received a company memo (after over a year of flying the NEO) that is has a “Rotation Mode” to prevent tail strike. Nothing was mentioned in the manual.........
Where are the howls of outrage over this 'cynical corporate cover-up' then, if adding automatic systems and not telling is so iniquitous?
Or could it be this falls into the same category as MCAS before the accidents? It's not hurt anyone so no one is outraged? (not suggesting this is an exact parallel but appears a similar concept). I expect Airbus' view on this was very similar to Boeing's on MCAS though; it is a sub-system of something else and failures in it can be identified and grouped under a common, pre-existing drill and as you have no control over it's operation what is the point of confusing people with knowledge of something they can't affect independently.

Last edited by meleagertoo; 7th May 2019 at 12:02.
meleagertoo is offline  
Old 7th May 2019, 09:46
  #5073 (permalink)  
 
Join Date: Jun 2001
Location: The middle
Posts: 369
Originally Posted by rog747 View Post
Are there any contributors here who are 737 pilots who transitioned to the MAX?

May I ask please,
If you did, did you have any SIM, classroom, or Line training on the MAX and it's differences, or was it purely on-line modules, thus was your first flight on a ''pax on board'' flight?

Were you made fully aware of the adverse pitch up changes, and CG issues of the new MAX due to the design enforced forward location of the new larger engines (which can now cause lift) at low weights/high power applications resulting in a (unrecoverable?) high AOA? (which we now are aware, necessitated the MCAS software patch)

Were you (before the 2 fatal and 1 nearly accidents) fully informed/trained on the new MCAS systems and it's functionality, implications, and what to do if it went rogue?

Thanks.
I did my MAX transition for an operator in the ME. No sim, classroom or line training, just CBT on company iPad that was mandated to be done in the pilots time off. Completed the CBT and then flew the NG for four months before first flight in the MAX, which was also the F/O’s first flight in the MAX.

until the Lion Air crash there was no mention of MCAS and as far as I remember no mention of the change in aerodynamics due to the new engines and their installation, at least not on the CBT or in any manuals from the company I was working for. Obviously other companies could have had different training material.
excrab is offline  
Old 7th May 2019, 09:52
  #5074 (permalink)  
Thread Starter
 
Join Date: Feb 2008
Location: DORSET
Age: 62
Posts: 42
Many thanks to you all for your honest and concise replies
rog747 is offline  
Old 7th May 2019, 10:52
  #5075 (permalink)  
 
Join Date: Dec 2014
Location: Hungary
Posts: 19
Originally Posted by 737 Driver View Post
Continuing the Threat and Error
What should one do when a barrier actually becomes a threat?
If you only have the runaway trim nnc , but now there is a crash few months earlier and some vague ad from the manufacturer.
Which might flag uas or it might flag as and it might leave you aircraft in a state you cant manually trim it back.
There is nowhere in the nnc saying if trim goes weird after raising flaps drop flaps back and reduce power.
maxxer is offline  
Old 7th May 2019, 11:30
  #5076 (permalink)  
Psychophysiological entity
 
Join Date: Jun 2001
Location: Tweet Rob_Benham Famous author. Well, slightly famous.
Age: 80
Posts: 4,693
Murphy's correction - Thanks.

Minor correction, after a couple of false starts the autopilot was engaged for more than 30 seconds, just long enough to provide a false sense of "not that bad"?
Then it all hit the fan on short order with AP disconnect followed by MCAS.

I had the AP time on as 3 seconds. Corrected. Indeed, the real 30 seconds it would give time for a feeling of having overcome the problem - until the 9 seconds of trim. But looking back again, it might be that feeling of success, coupled with the fact STS runs the wheels (albeit briefly) anyway, that made him miss the sheer length of the run time. Hard to imagine missing that clunking, but the Stick Shake is quite loud, and as we've discussed, very distracting.

Let's face it. Than run time of 9 seconds, the lack of sustained ANU via the electric trim and the power so high are the main indicators of his state of mind. It's a terrible shame that he'd not got more height as I've a feeling he was starting to go down the right logic route. But only just starting, and coping with too much of a handful to really focus.

Yes, AVIATE comes first, and it's really shouting loud that the stresses were drowning what skill he had.
Loose rivets is offline  
Old 7th May 2019, 12:05
  #5077 (permalink)  
 
Join Date: Jun 2010
Location: Netherlands
Age: 37
Posts: 4
Originally Posted by meleagertoo View Post
And as such, why is it really so necessary to inform pilots of this system? There is no specific control over it, just the generic runaway trim procedure.
Isn't that exactly the problem (next to MCAS operation relying on a single AoA vane naturally)?
Obviously, in case of the 737 MAX MCAS accidents there was a lack of a clean manual override path similar to that present in case of the 737 NG STS and/or allegedly the MCAS variant installed on the KC-46 tanker where, in both cases, the automatic trim procedure could be overridden by manual column input? Had that been in place in case of the 737 MAX MCAS along with appropriate pilot training and full disclosure of the new system(s) and changes, I dare say we would not be having this lengthy thread here.

Wasn't Boeing's design philosophy supposed to be "pilot can always override automation"? And why was it so poorly respected in this instance as opposed to the cases when similar systems were introduced by Boeing in the past ? These are the questions one truly needs to raise to assess the "what went wrong here?" conundrum.

Last edited by Portallo; 7th May 2019 at 12:07. Reason: fixed typos
Portallo is offline  
Old 7th May 2019, 13:11
  #5078 (permalink)  
 
Join Date: May 2010
Location: Boston
Age: 68
Posts: 410
Originally Posted by 737 Driver View Post
I agree it is an incomplete picture (which I did acknowledge), but there are some broad enough outlines from which we can draw some conclusions. If anything comes out that substantially alters our current understanding, then I'll be happy to make a correction.

As far as what was going on while the the trim switches were in the cutout position, are you referring to the gradual movement from 2.3 to 2.1 units? It apparently occurred over two and half minutes. I'm interested in seeing what the board's thoughts are on that as well, but I should point out that in the context of the overall trim movement, it is a very small and slow creep.
I was actually wondering more about what was discussed and actioned during that time. Two and and half minutes is long enough for the initial startle factor to dissipate, hopefully some insight can be gained into pilots actions during the preceding critical time.
The prelim report mentions only one attempt at manual trim at 05:41:46, roughly half way through the cutout period, surely there was other activity during that 150 seconds.

One possibility is that the trim creep was due to attempts at manual trim causing a bounce in the cables that each time resulted in slight movement in the wrong direction. In the mentour pilot video you can see this bounce as attempts are made.

Another possibility is that one of the brakes is not holding against the load but that would be a seperate failure/design flaw that is probably not needed to explain the traces.
Access to the raw FDR data should resolve this since if it was a slipping brake it would likely be continuous whereas manual trim efforts would be seen as (slight) steps with pauses.
MurphyWasRight is offline  
Old 7th May 2019, 13:12
  #5079 (permalink)  
 
Join Date: Jan 2010
Location: UK
Posts: 114
Originally Posted by meleagertoo View Post
Which rather vindicates Boeing's position on this; they reacted exactly as Boeing intended by identifying it as an STS runaway (which most assuredly is a runaway trim event) and dealt with it by using the correct pre-existing technique.


And as such, why is it really so necessary to inform pilots of this system? There is no specific control over it, just the generic runaway trim procedure. Surely telling people about systems they have no specific influence over is merely muddying the waters? If it presents itself as failure event X which is dealt with by checklist Y does anyone need to know that it could be system A or A.1 at fault, when both are addressed by the same checklist, show effectively the same symptoms and actually are components of the same system?

That, I am sure, was Boeing's rationale and though I'm not 100% comfortable with it I'm certainly not condemning it in the absolute and fundamental way some others are.
Except it was the jumpseater that identified the issue NOT the crew and it seems that neither the crew or the jumpseater understood what the issue was. No mention of stab trim runaway was made in the writeup as I recall.

SamYeager is offline  
Old 7th May 2019, 13:14
  #5080 (permalink)  
 
Join Date: Apr 2019
Location: USA
Posts: 217
Originally Posted by rog747 View Post
Are there any contributors here who are 737 pilots who transitioned to the MAX?

May I ask please,
If you did, did you have any SIM, classroom, or Line training on the MAX and it's differences, or was it purely on-line modules, thus was your first flight on a ''pax on board'' flight?

Were you made fully aware of the adverse pitch up changes, and CG issues of the new MAX due to the design enforced forward location of the new larger engines (which can now cause lift) at low weights/high power applications resulting in a (unrecoverable?) high AOA? (which we now are aware, necessitated the MCAS software patch)

Were you (before the 2 fatal and 1 nearly accidents) fully informed/trained on the new MCAS systems and it's functionality, implications, and what to do if it went rogue?

Thanks.
MAX was added to our fleet of NG's about a year ago. All training was either online or bulletins pushed to our Ipads. There is a quick reference card in the cockpit with key reminders. I had a couple of opportunities to fly the MAX before it was grounded. It actually flies very nicely, and the only real issue for me was that some of the switches and indicators were in different places. It would be comparable to transitioning from a 2001 Ford F-150 to a 2019 model. Drives pretty much the same, some new bells and whistles, some new switchology for the radios and climate control, but still a Ford F-150.

Our company continually stressed that the transition would be relatively straightforward, and to a certain point that was true in the context of normal operations. However, my contention always was (and this is not 20/20 hindsight) that any issues with the MAX would be less a case of normals operations, but rather non-normal ops. As we have seen in aviation time and time again, it is very difficult to predict all the unique failure modes that may arise with a new aircraft. Given that, my concern with the MAX was not with adapting to any differences when things were going right, but rather how different it might be when things were going wrong. Sadly, those concerns were not misplaced.
737 Driver is offline  

Thread Tools
Search this Thread

Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service

Copyright © 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.