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morrisond
Posts: 1341
Joined: Thu Jan 07, 2010 12:22 am

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Wed May 01, 2019 8:26 pm

Jamie514 wrote:
morrisond wrote:
Jamie514 wrote:


If only you applied that type of critical thinking to the statements from Boeing that you treat as gospel.


I'm not treating them as Gospel - I said they might be lying.

However I'm pretty sure the Lawyers would never have allowed Mullenburg to say what he did the other day unless they were sure they designed to the existing standards and requirements. Were those existing standards and requirements sufficient - Obviously no as they also assumed a basic level of Pilot competency that does not exist.

The Shareholders lawsuits will be massive if he is intentionally found to be lying.


Right.

I'm pretty sure Ethiopians lawyers would never have allowed their official twitter to say what it did in March unless they were sure the training delivered was to the existing standard and requirement. Were those existing standards and requirements sufficient? Probably not. According to Reuters (which has a sterling reputation) the APA have the nerve to be calling for more training than what is being proposed now let alone what Boeing offered in MCAS for Dummies last fall.

Has AVHerald actually concluded that Pilot training provided by Ethiopian was the primary cause of the crash? Far as I could see, he only sees it as a POSSIBLE contributing factor, which I would agree with.


I would bet Ethiopian Airlines is not as worried about getting sued as Boeing.

From AVHerald

"On Apr 11th 2019 The Aviation Herald received a full copy of the Flight Operations Manual (FOM), Revision 18B released on Nov 30th 2018, which is currently being used by Ethiopian Airlines (verified in April 2019 to be current). Although Boeing had issued an operator's bulletin on Nov 6th 2018, which was put into Emergency Airworthiness Directive 2018-23-51 dated Nov 7th 2018 requiring the stab trim runaway procedure to be incorporated into the FOM ahead of the sign off of this version of the FOM (the entire document is on file but not available for publishing), there is no trace of such an addition in the entire 699 pages of the FOM.

Quite the opposite, in section 2.6 of the FOM "Operational Irregularities" the last revision is provided as Revision 18 dated "Nov 1st 2017".

According to information The Aviation Herald had received in March 2019, the Airline Management needed to be reminded to distribute the Boeing Operator's Bulletin as well as the EAD to their pilots, eventually the documents were distributed to the flight crew. However, it was never verified, whether those documents had arrived, were read or had been understood. No deeper explanation of the MCAS, mentioned but not explained in both documents, was offered.

It turned out, that only very cursory knowledge about the stab trim runaway procedure exists amongst the flight crew of Ethiopian Airlines even 5 months after the EAD was distributed. In particular, none of the conditions suggesting an MCAS related stab trim runaway was known with any degree of certainty. In that context the recommendation by the accident flight's first officer to use the TRIM CUTOUT switches suggests, that he was partially aware of the contents of the EAD and reproduced some but not all of the provisions and not all of the procedure, which may or may not explain some of the obvious omissions in following the procedure in full."
 
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Aesma
Posts: 11833
Joined: Sat Nov 14, 2009 6:14 am

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Wed May 01, 2019 8:43 pm

I don't know if someone has done the exercise before, but imagine that the A320 had a similar problem with the neo (new engine option) and that the FBW couldn't be changed, so Airbus added something a lot like MCAS. What are the chances a similar accident could happen ?

From what I know there are three AoA sensors, linked to three flight computers, and making sure they agree is one of their basic functions. If there is a double disagreement, then the aircraft will change flight laws, deactivate envelope protections, and give the pilots more direct control, by saying so. Plenty of info about what is going on will show up on the EICAS.

It's so fundamentally different, it highlights the generational differences between the two aircraft.
New Technology is the name we give to stuff that doesn't work yet. Douglas Adams
 
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PixelFlight
Posts: 623
Joined: Thu Nov 08, 2018 11:09 pm

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Wed May 01, 2019 8:45 pm

XRAYretired wrote:
Many of our experts have taken the trouble to advise the rest of us how they would have done it, saved the world and got the girl -easy. Few have got beyond into what the crews might have actually been doing and why, and fewer still have got beyond '3rd world Pilots', 'Not done 1500 hours in crop dusters', lack of training. Not retracting flaps is a common position in this regard.

I would find it of interest if our experts could actually speculate a little on what the crews might actually have been doing with the conditions they were faced with and resulting in the actions we can deduce from the information published so far.

If they would, they might start with looking at the first few minutes of the flights. We now have 4 to look at (thanks to seahawk posting report for SWG531 March 2011, 737-8Q8) with similar conditions Stick Shaker/IAS Disagree etc. during T/O and Initial Climb. So 4 crews on 3 continents, 10 years.

In all 4 cases it appears that the crews have reacted in a very similar manner, Climb is maintained, Thrust is maintained (speed increased) and Flaps Retracted. In 2 of 4, AP is at least commanded.

Looks remarkably like Training/Procedure? to me?

Ray

:checkmark: Kudo for this post :thumbsup:
Take all the raw facts and start thinking about "how" a pilot think. - makes decisions, evaluates, prioritizes plans... "what" is important to him and "why".

" If you tell me, I will listen. "
" If you show me, I will see. "
" If you let me experience, I will learn. "
To date the only publicly available simulated experience of something that try to show a MCAS malfunction at high speed is the Mentour Pilot video, and we learned a lot from it. But this was not a 737 MAX simulator and there did not simulate an erroneous high AoA fault at takeoff.
 
XRAYretired
Posts: 615
Joined: Fri Mar 15, 2019 11:21 am

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Wed May 01, 2019 8:49 pm

From the PreliminaryReport.

1.16.2 OPERATION MANUAL EXTRACTS
1.16.2.1 ETHIOPIAN AIRLINES AIRCRAFT FLIGHT MANUAL (AFM)
A check of the AFM provided by Ethiopian Airlines showed that the airline had incorporated the revisions A180625 on November, 11 2018 required by Airworthiness Directive 2018-23-51. The two pages from the AFM are in Appendix .
1.16.2.2 FCOM BULLETIN ISSUED BY BOEING TO ETHIOPIAN AIRLINES An FCOM bulletin issued by Boeing to Ethiopian Airlines (ETH-12) regarding uncommanded nosedown stabilizer trim required Ethiopian Airlines to insert the bulletin in their B737MAX FCOM. The US Ops/hp technical advisors were provided an electronic copy of the Airline’s B737MAX FCOM, and the bulletin was found to be incorporated per Boeing directions.
The bulletin is shown in Appendix 4


Appendix 4 marked D6-27370-MAX-ETH February 21st 2019.
 
morrisond
Posts: 1341
Joined: Thu Jan 07, 2010 12:22 am

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Wed May 01, 2019 8:58 pm

XRAYretired wrote:
From the PreliminaryReport.

1.16.2 OPERATION MANUAL EXTRACTS
1.16.2.1 ETHIOPIAN AIRLINES AIRCRAFT FLIGHT MANUAL (AFM)
A check of the AFM provided by Ethiopian Airlines showed that the airline had incorporated the revisions A180625 on November, 11 2018 required by Airworthiness Directive 2018-23-51. The two pages from the AFM are in Appendix .
1.16.2.2 FCOM BULLETIN ISSUED BY BOEING TO ETHIOPIAN AIRLINES An FCOM bulletin issued by Boeing to Ethiopian Airlines (ETH-12) regarding uncommanded nosedown stabilizer trim required Ethiopian Airlines to insert the bulletin in their B737MAX FCOM. The US Ops/hp technical advisors were provided an electronic copy of the Airline’s B737MAX FCOM, and the bulletin was found to be incorporated per Boeing directions.
The bulletin is shown in Appendix 4


Appendix 4 marked D6-27370-MAX-ETH February 21st 2019.


Sure - it's easy to change things after the fact. Where did the AVHerald copy come from? Maybe this is why the pre-liminary report was delayed as they had to paper it.
 
morrisond
Posts: 1341
Joined: Thu Jan 07, 2010 12:22 am

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Wed May 01, 2019 9:03 pm

PixelFlight wrote:
XRAYretired wrote:
Many of our experts have taken the trouble to advise the rest of us how they would have done it, saved the world and got the girl -easy. Few have got beyond into what the crews might have actually been doing and why, and fewer still have got beyond '3rd world Pilots', 'Not done 1500 hours in crop dusters', lack of training. Not retracting flaps is a common position in this regard.

I would find it of interest if our experts could actually speculate a little on what the crews might actually have been doing with the conditions they were faced with and resulting in the actions we can deduce from the information published so far.

If they would, they might start with looking at the first few minutes of the flights. We now have 4 to look at (thanks to seahawk posting report for SWG531 March 2011, 737-8Q8) with similar conditions Stick Shaker/IAS Disagree etc. during T/O and Initial Climb. So 4 crews on 3 continents, 10 years.

In all 4 cases it appears that the crews have reacted in a very similar manner, Climb is maintained, Thrust is maintained (speed increased) and Flaps Retracted. In 2 of 4, AP is at least commanded.

Looks remarkably like Training/Procedure? to me?

Ray


:checkmark: Kudo for this post :thumbsup:
Take all the raw facts and start thinking about "how" a pilot think. - makes decisions, evaluates, prioritizes plans... "what" is important to him and "why".

" If you tell me, I will listen. "
" If you show me, I will see. "
" If you let me experience, I will learn. "
To date the only publicly available simulated experience of something that try to show a MCAS malfunction at high speed is the Mentour Pilot video, and we learned a lot from it. But this was not a 737 MAX simulator and there did not simulate an erroneous high AoA fault at takeoff.


Both SWG531 and Lionair reduced thrust and it looks like Lionair tried flaps again as well which looks like it turned off MCAS, but when they put them back up it starting acting again.

The Lionair Report would be a lot more helpful if it actually had numbers on the scales of the FDR traces but it doesn't look like they were over or anywhere near Vmo.
 
kalvado
Posts: 1996
Joined: Wed Mar 01, 2006 4:29 am

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Wed May 01, 2019 9:09 pm

Aesma wrote:
I don't know if someone has done the exercise before, but imagine that the A320 had a similar problem with the neo (new engine option) and that the FBW couldn't be changed, so Airbus added something a lot like MCAS. What are the chances a similar accident could happen ?

From what I know there are three AoA sensors, linked to three flight computers, and making sure they agree is one of their basic functions. If there is a double disagreement, then the aircraft will change flight laws, deactivate envelope protections, and give the pilots more direct control, by saying so. Plenty of info about what is going on will show up on the EICAS.

It's so fundamentally different, it highlights the generational differences between the two aircraft.

Let me put it so:
There are so many ways to do things wrong, that you never know. If Airbus (or any other company) tasked an undergrad intern suffering from substance overuse to write MCAS-like code without review or supervision, a result will be equally, if not more catastrophic.
If any company tasked a reasonably professional group to do a proper development of a piece of code for a flight control system, with required checks, algorithms and test laid out before launching code editor, and with a trained tester doing some moderately paranoiac job, there will be very little chance of things going crazy.
Mistakes always happen, but in this case of sole input into a system even relatively benign testing would help. Of course, there could be "too easy to bother" approach - and a job of project leader should be to provide a stark reminder that because of the nail the kingdom falls.
 
XRAYretired
Posts: 615
Joined: Fri Mar 15, 2019 11:21 am

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Wed May 01, 2019 9:14 pm

morrisond wrote:
XRAYretired wrote:
From the PreliminaryReport.

1.16.2 OPERATION MANUAL EXTRACTS
1.16.2.1 ETHIOPIAN AIRLINES AIRCRAFT FLIGHT MANUAL (AFM)
A check of the AFM provided by Ethiopian Airlines showed that the airline had incorporated the revisions A180625 on November, 11 2018 required by Airworthiness Directive 2018-23-51. The two pages from the AFM are in Appendix .
1.16.2.2 FCOM BULLETIN ISSUED BY BOEING TO ETHIOPIAN AIRLINES An FCOM bulletin issued by Boeing to Ethiopian Airlines (ETH-12) regarding uncommanded nosedown stabilizer trim required Ethiopian Airlines to insert the bulletin in their B737MAX FCOM. The US Ops/hp technical advisors were provided an electronic copy of the Airline’s B737MAX FCOM, and the bulletin was found to be incorporated per Boeing directions.
The bulletin is shown in Appendix 4


Appendix 4 marked D6-27370-MAX-ETH February 21st 2019.


Sure - it's easy to change things after the fact. Where did the AVHerald copy come from? Maybe this is why the pre-liminary report was delayed as they had to paper it.


Ask AvH. I doubt they will reveal their source or how much. Would you like to tell NTSB and FAA that they have been hoodwinked for us.

Ray
 
XRAYretired
Posts: 615
Joined: Fri Mar 15, 2019 11:21 am

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Wed May 01, 2019 9:16 pm

morrisond wrote:
PixelFlight wrote:
XRAYretired wrote:
Many of our experts have taken the trouble to advise the rest of us how they would have done it, saved the world and got the girl -easy. Few have got beyond into what the crews might have actually been doing and why, and fewer still have got beyond '3rd world Pilots', 'Not done 1500 hours in crop dusters', lack of training. Not retracting flaps is a common position in this regard.

I would find it of interest if our experts could actually speculate a little on what the crews might actually have been doing with the conditions they were faced with and resulting in the actions we can deduce from the information published so far.

If they would, they might start with looking at the first few minutes of the flights. We now have 4 to look at (thanks to seahawk posting report for SWG531 March 2011, 737-8Q8) with similar conditions Stick Shaker/IAS Disagree etc. during T/O and Initial Climb. So 4 crews on 3 continents, 10 years.

In all 4 cases it appears that the crews have reacted in a very similar manner, Climb is maintained, Thrust is maintained (speed increased) and Flaps Retracted. In 2 of 4, AP is at least commanded.

Looks remarkably like Training/Procedure? to me?

Ray


:checkmark: Kudo for this post :thumbsup:
Take all the raw facts and start thinking about "how" a pilot think. - makes decisions, evaluates, prioritizes plans... "what" is important to him and "why".

" If you tell me, I will listen. "
" If you show me, I will see. "
" If you let me experience, I will learn. "
To date the only publicly available simulated experience of something that try to show a MCAS malfunction at high speed is the Mentour Pilot video, and we learned a lot from it. But this was not a 737 MAX simulator and there did not simulate an erroneous high AoA fault at takeoff.


Both SWG531 and Lionair reduced thrust and it looks like Lionair tried flaps again as well which looks like it turned off MCAS, but when they put them back up it starting acting again.

The Lionair Report would be a lot more helpful if it actually had numbers on the scales of the FDR traces but it doesn't look like they were over or anywhere near Vmo.


Expert analysis only please. First few minutes.
 
Jamie514
Posts: 148
Joined: Thu May 18, 2017 4:36 pm

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Wed May 01, 2019 10:30 pm

morrisond wrote:

I would bet Ethiopian Airlines is not as worried about getting sued as Boeing.


It seems they told the truth.

morrisond wrote:
From AVHerald

"On Apr 11th 2019 The Aviation Herald received a full copy of the Flight Operations Manual (FOM), Revision 18B released on Nov 30th 2018, which is currently being used by Ethiopian Airlines (verified in April 2019 to be current).


It may be a fantastic source of reporting, but any new information must be independently verified. It is impossible to do so with undisclosed sources. And it turns out it may not be accurate.

XRAYretired wrote:
From the PreliminaryReport.

1.16.2 OPERATION MANUAL EXTRACTS
1.16.2.1 ETHIOPIAN AIRLINES AIRCRAFT FLIGHT MANUAL (AFM)
A check of the AFM provided by Ethiopian Airlines showed that the airline had incorporated the revisions A180625 on November, 11 2018 required by Airworthiness Directive 2018-23-51. The two pages from the AFM are in Appendix .
1.16.2.2 FCOM BULLETIN ISSUED BY BOEING TO ETHIOPIAN AIRLINES An FCOM bulletin issued by Boeing to Ethiopian Airlines (ETH-12) regarding uncommanded nosedown stabilizer trim required Ethiopian Airlines to insert the bulletin in their B737MAX FCOM. The US Ops/hp technical advisors were provided an electronic copy of the Airline’s B737MAX FCOM, and the bulletin was found to be incorporated per Boeing directions.
The bulletin is shown in Appendix 4


Appendix 4 marked D6-27370-MAX-ETH February 21st 2019.


Thank you very much for this.
 
Chemist
Posts: 575
Joined: Tue Oct 20, 2015 4:46 am

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Wed May 01, 2019 10:38 pm

kalvado wrote:
morrisond wrote:
I suspect Crew training standards were improving for quite some time on that graph along with more reliable safe designs. Crew training standards just seem to have taken a nosedive in the last 20 years.

You are still not answering the Question - Do you believe existing crew training standards are sufficient? What type of emergencies do you think they should they be able to handle if any at all?

Crew training standard, design parameters and risks converge to statistical number - probability for passenger to arrive in one piece. So far, typical crew training seems adequate for modern jets (A320 and later, 777, 737NG); ....


Asiana crashed a perfectly healthy 777 on a clear calm day due to training deficiencies and piloting errors.
 
morrisond
Posts: 1341
Joined: Thu Jan 07, 2010 12:22 am

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Wed May 01, 2019 10:47 pm

Jamie514 wrote:
morrisond wrote:

I would bet Ethiopian Airlines is not as worried about getting sued as Boeing.


It seems they told the truth.

morrisond wrote:
From AVHerald

"On Apr 11th 2019 The Aviation Herald received a full copy of the Flight Operations Manual (FOM), Revision 18B released on Nov 30th 2018, which is currently being used by Ethiopian Airlines (verified in April 2019 to be current).


It may be a fantastic source of reporting, but any new information must be independently verified. It is impossible to do so with undisclosed sources. And it turns out it may not be accurate.

XRAYretired wrote:
From the PreliminaryReport.

1.16.2 OPERATION MANUAL EXTRACTS
1.16.2.1 ETHIOPIAN AIRLINES AIRCRAFT FLIGHT MANUAL (AFM)
A check of the AFM provided by Ethiopian Airlines showed that the airline had incorporated the revisions A180625 on November, 11 2018 required by Airworthiness Directive 2018-23-51. The two pages from the AFM are in Appendix .
1.16.2.2 FCOM BULLETIN ISSUED BY BOEING TO ETHIOPIAN AIRLINES An FCOM bulletin issued by Boeing to Ethiopian Airlines (ETH-12) regarding uncommanded nosedown stabilizer trim required Ethiopian Airlines to insert the bulletin in their B737MAX FCOM. The US Ops/hp technical advisors were provided an electronic copy of the Airline’s B737MAX FCOM, and the bulletin was found to be incorporated per Boeing directions.
The bulletin is shown in Appendix 4


Appendix 4 marked D6-27370-MAX-ETH February 21st 2019.


Thank you very much for this.


You've got it backwards - the AVHerald report came after the official Pre-lim report - they are basically saying the pre-lim report is full of s**t.

Nice partial quoting btw.
 
morrisond
Posts: 1341
Joined: Thu Jan 07, 2010 12:22 am

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Wed May 01, 2019 10:52 pm

Aesma wrote:
I don't know if someone has done the exercise before, but imagine that the A320 had a similar problem with the neo (new engine option) and that the FBW couldn't be changed, so Airbus added something a lot like MCAS. What are the chances a similar accident could happen ?

From what I know there are three AoA sensors, linked to three flight computers, and making sure they agree is one of their basic functions. If there is a double disagreement, then the aircraft will change flight laws, deactivate envelope protections, and give the pilots more direct control, by saying so. Plenty of info about what is going on will show up on the EICAS.

It's so fundamentally different, it highlights the generational differences between the two aircraft.


I take it You have never heard of the QF71/72 incidents then.
 
morrisond
Posts: 1341
Joined: Thu Jan 07, 2010 12:22 am

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Wed May 01, 2019 11:00 pm

XRAYretired wrote:
morrisond wrote:
XRAYretired wrote:
From the PreliminaryReport.

1.16.2 OPERATION MANUAL EXTRACTS
1.16.2.1 ETHIOPIAN AIRLINES AIRCRAFT FLIGHT MANUAL (AFM)
A check of the AFM provided by Ethiopian Airlines showed that the airline had incorporated the revisions A180625 on November, 11 2018 required by Airworthiness Directive 2018-23-51. The two pages from the AFM are in Appendix .
1.16.2.2 FCOM BULLETIN ISSUED BY BOEING TO ETHIOPIAN AIRLINES An FCOM bulletin issued by Boeing to Ethiopian Airlines (ETH-12) regarding uncommanded nosedown stabilizer trim required Ethiopian Airlines to insert the bulletin in their B737MAX FCOM. The US Ops/hp technical advisors were provided an electronic copy of the Airline’s B737MAX FCOM, and the bulletin was found to be incorporated per Boeing directions.
The bulletin is shown in Appendix 4


Appendix 4 marked D6-27370-MAX-ETH February 21st 2019.


Sure - it's easy to change things after the fact. Where did the AVHerald copy come from? Maybe this is why the pre-liminary report was delayed as they had to paper it.


Ask AvH. I doubt they will reveal their source or how much. Would you like to tell NTSB and FAA that they have been hoodwinked for us.

Ray


Look at the Feb 21 st date - that may bewhen they finally revised it - after they were reminded and no proof they distributed it.

The Ethiopian report is very suspect just on the one statement "They followed all procedures"
 
kayik
Posts: 52
Joined: Thu Mar 14, 2019 10:58 pm

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Wed May 01, 2019 11:01 pm

morrisond wrote:
Aesma wrote:
I don't know if someone has done the exercise before, but imagine that the A320 had a similar problem with the neo (new engine option) and that the FBW couldn't be changed, so Airbus added something a lot like MCAS. What are the chances a similar accident could happen ?

From what I know there are three AoA sensors, linked to three flight computers, and making sure they agree is one of their basic functions. If there is a double disagreement, then the aircraft will change flight laws, deactivate envelope protections, and give the pilots more direct control, by saying so. Plenty of info about what is going on will show up on the EICAS.

It's so fundamentally different, it highlights the generational differences between the two aircraft.


I take it You have never heard of the QF71/72 incidents then.


The writer here implies that chances of a similar accident is zilch since there was no accident and the aircraft was not an A320.
 
RickNRoll
Posts: 1783
Joined: Fri Jan 06, 2012 9:30 am

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 12:26 am

morrisond wrote:
Jamie514 wrote:
morrisond wrote:

I would bet Ethiopian Airlines is not as worried about getting sued as Boeing.


It seems they told the truth.

morrisond wrote:
From AVHerald

"On Apr 11th 2019 The Aviation Herald received a full copy of the Flight Operations Manual (FOM), Revision 18B released on Nov 30th 2018, which is currently being used by Ethiopian Airlines (verified in April 2019 to be current).


It may be a fantastic source of reporting, but any new information must be independently verified. It is impossible to do so with undisclosed sources. And it turns out it may not be accurate.

XRAYretired wrote:
From the PreliminaryReport.

1.16.2 OPERATION MANUAL EXTRACTS
1.16.2.1 ETHIOPIAN AIRLINES AIRCRAFT FLIGHT MANUAL (AFM)
A check of the AFM provided by Ethiopian Airlines showed that the airline had incorporated the revisions A180625 on November, 11 2018 required by Airworthiness Directive 2018-23-51. The two pages from the AFM are in Appendix .
1.16.2.2 FCOM BULLETIN ISSUED BY BOEING TO ETHIOPIAN AIRLINES An FCOM bulletin issued by Boeing to Ethiopian Airlines (ETH-12) regarding uncommanded nosedown stabilizer trim required Ethiopian Airlines to insert the bulletin in their B737MAX FCOM. The US Ops/hp technical advisors were provided an electronic copy of the Airline’s B737MAX FCOM, and the bulletin was found to be incorporated per Boeing directions.
The bulletin is shown in Appendix 4


Appendix 4 marked D6-27370-MAX-ETH February 21st 2019.


Thank you very much for this.


You've got it backwards - the AVHerald report came after the official Pre-lim report - they are basically saying the pre-lim report is full of s**t.

Nice partial quoting btw.


If it is, then it is just s**t all the way down from Boeings initial design to the crash.
 
morrisond
Posts: 1341
Joined: Thu Jan 07, 2010 12:22 am

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 12:28 am

kayik wrote:
morrisond wrote:
Aesma wrote:
I don't know if someone has done the exercise before, but imagine that the A320 had a similar problem with the neo (new engine option) and that the FBW couldn't be changed, so Airbus added something a lot like MCAS. What are the chances a similar accident could happen ?

From what I know there are three AoA sensors, linked to three flight computers, and making sure they agree is one of their basic functions. If there is a double disagreement, then the aircraft will change flight laws, deactivate envelope protections, and give the pilots more direct control, by saying so. Plenty of info about what is going on will show up on the EICAS.

It's so fundamentally different, it highlights the generational differences between the two aircraft.


I take it You have never heard of the QF71/72 incidents then.


The writer here implies that chances of a similar accident is zilch since there was no accident and the aircraft was not an A320.


Yes - but it was an Airbus 330 with a FBW system where it tried to put the plane in the ground.
 
morrisond
Posts: 1341
Joined: Thu Jan 07, 2010 12:22 am

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 2:12 am

RickNRoll wrote:
morrisond wrote:
Jamie514 wrote:

It seems they told the truth.



It may be a fantastic source of reporting, but any new information must be independently verified. It is impossible to do so with undisclosed sources. And it turns out it may not be accurate.



Thank you very much for this.


You've got it backwards - the AVHerald report came after the official Pre-lim report - they are basically saying the pre-lim report is full of s**t.

Nice partial quoting btw.


If it is, then it is just s**t all the way down from Boeings initial design to the crash.


Yes it is. Basically no one is taking safety seriously enough.
 
User avatar
PixelFlight
Posts: 623
Joined: Thu Nov 08, 2018 11:09 pm

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 5:00 am

morrisond wrote:
kayik wrote:
morrisond wrote:

I take it You have never heard of the QF71/72 incidents then.


The writer here implies that chances of a similar accident is zilch since there was no accident and the aircraft was not an A320.


Yes - but it was an Airbus 330 with a FBW system where it tried to put the plane in the ground.

ADIRU fault generating unbelievable, still unexplained, repetitive spike data without triggering any integrity test + FC algorithm design error that was never catch before because nobody was able to think that a such repetitive spike data could be possible in reality. The algorithm was corrected. This ADIRU was analyzed but never sent such repetitive spike data anymore, nobody known why. Safety assessment was evaluated and found ok.
 
oschkosch
Posts: 287
Joined: Mon Oct 29, 2018 3:41 pm

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 5:50 am

https://www.airlineratings.com/news/boe ... -problems/

Boeing has appointed its high-powered general counsel to a new role tasked with handling legal issues associated with the Boeing 737 MAX crisis. Michael Luttig will also act as a senior advisor to Boeing chief executive Dennis Muilenburg and the Boeing board as they pick their way through the legal and public relations minefield caused by the crashes. The appointment comes as Boeing faces multiple lawsuits over the crashes of Lion Air Flight 610 last October and Ethiopian Airlines Flight 302 in March. It also faces investigations into its relationship with the US Federal Aviation Administration and certification of 737 MAX aircraft.



https://www.euronews.com/2019/05/01/us- ... ax-sources

The U.S. House Transportation and Infrastructure Committee is tentatively planning a May 15 hearing on the now grounded Boeing 737 MAX and the Federal Aviation Administration's aircraft certification program, three people briefed on the matter said on Wednesday.

A spokeswoman for Representative Peter DeFazio, who chairs the panel, declined to comment on the date. DeFazio told reporters on Tuesday he planned to hold a hearing on the Boeing 737 MAX and the certification process in the near future.

The hearing is expected to include Acting FAA Administrator Dan Elwell, National Transportation Safety Board chairman Robert Sumwalt and Earl Lawrence, who was named executive director of the FAA's Aircraft Certification Service in 2018, the sources said.

Last month, U.S. Transportation Secretary Elaine Chao named a panel of experts to a blue-ribbon committee to review the aircraft certification process after two deadly Boeing 737 MAX crashes killed nearly 350 people.

In a March 28 memo to Elwell reviewed by Reuters, Chao said she wanted an "action plan" from the FAA "to reassure congressional oversight committees that the FAA's culture of safety remains not only robust but forward-looking" and to restore "public trust in aviation safety."

She also asked what "measures are needed to reinforce the culture of safety and constantly improve the FAA's oversight functions and offices, including the certification process."
 
OldAeroGuy
Posts: 3886
Joined: Sun Dec 05, 2004 6:50 am

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 5:56 am

kalvado wrote:
Well, we heard that. Can you calculate climb profile with gear and flaps out for that day's temperature ADD altitude and given terrain around? I still want to see how that would work.


I've worked this out for you previously. Why do you keep bringing it up?

1) Climb profiles to avoid obstacles and clear terrain are calculated with one engine inoperative. The Climb profiles would have been calculated before takeoff for the Weight, Altitude & Temperature (WAT) at ADD on the day in question.
2) The extra thrust from having two engines operating more than offsets the extra drag from leaving the Flaps at the takeoff setting and leaving the Gear down. Basically, It's excess engine thrust that allows the airplane to climb.
Airplane design is easy, the difficulty is getting them to fly - Barnes Wallis
 
PStechPaul
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 6:39 am

As I understand it, the ET304 aircraft had auto-throttle engaged during the emergency. But wouldn't auto-throttle reduce thrust when maximum airspeed was reached? That seems like a reasonable and logical safeguard, but then the MCAS implementation was also flawed and dangerous.
 
Jetty
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 6:52 am

morrisond wrote:
Yes it is. Basically no one is taking safety seriously enough.

You’ve made over 200 posts in this topic with exactly this assertion. Is it really necessary to repeat it whenever you have the chance? In the last few posts there’s even a streak with you writing 5 out of 7 posts in a row without adding something substantive to what anyone that follows this thread already knew about your stance. Your views are appreciated but please don’t see it as a requirement to respond to every post.
 
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zeke
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 7:20 am

morrisond wrote:
Yes - but it was an Airbus 330 with a FBW system where it tried to put the plane in the ground.


It didnt actually, it reduced the angle attack via an elevator input as it detected a stall, which the pilots were able to counter by putting in elevator input in the opposite direction. Any change in attitude at cruise speeds results in significant rates of climb or descent, hence the reason why TCAS events at high altitudes often result in passenger injuries, and the reason why Airbus developed the auto TCAS. Please remember the difference between elevator and stabilizer, MCAS dives the stabilizer.
Human rights lawyers are "ambulance chasers of the very worst kind.'" - Sky News
 
sgrow787
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 8:41 am

PW100 wrote:
And yet, aviation, transportation, infrastructure, construction, you name it, has never been more safe than today. We tend to lose sight on how safe these things are. Really.

Side-step: we want government to protect us against a handfull of aviations accidents (or terrorist related deaths), but without even blinking an eye readily accept thousands and thousands of road deaths as normal practice. Go figure.


I get so tired of hearing people compare commercial air miles to miles in cars on busy multi-lane mult-connected roadways. Why don't we compare using the time spent (ie hours)?

Car passengers
Car owners in 2018: 276,100,000
Avg miles per passenger per year: 10,000 miles
Avg speed: 30 mph
Hours driving per year per passenger: 333 hours
Total hours driving per year: 92,033,333,333 hours
Deaths per year (not including alcohol related): 40000 - 10000 = 30000
# driving hours per death: 3,067,778

Plane passengers
Airplane deaths per trillion revenue passenger kilometers in 2018: 60
(from https://en.wikipedia.org/wiki/Aviation_ ... t_(cropped).png)
Airplane deaths per trillion revenue passenger miles in 2018: 60 * 1.60934 = 97
Avg # passengers per flight: 100
Avg flight time: 2 hours
Avg flight cruise speed: 475 kts
Avg flight cruise time: 1.67 hours
Avg flight cruise distance: 793 miles
Avg descent and approach speed: 200 kts
Avg descent and approach time: 0.33 hours (20 minutes)
Avg descent and approach distance: 66 miles
Avg flight speed: 430 kts
Avg # flights per day: 43000 (from https://www.faa.gov/air_traffic/by_the_numbers)
Total # flights per year: 15,695,000
Total flight miles per year: 13,485,928,750
Total Revenue Passenger Miles: 1,348,592,875,000
Total Expected Passenger Deaths: 130
Total Revenue Passenger Hours: 3,139,000,000
# passenger flying hours per death: 24,105,237

Summary: Airplane travel is safer than automobile travel by a factor of 8 to 1.
Just one sensor,
Oh just one se-en-sor,
Just one sensor,
Ooh ooh oo-ooh
Oo-oo-ooh.
 
kalvado
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 10:29 am

OldAeroGuy wrote:
kalvado wrote:
Well, we heard that. Can you calculate climb profile with gear and flaps out for that day's temperature ADD altitude and given terrain around? I still want to see how that would work.


I've worked this out for you previously. Why do you keep bringing it up?

1) Climb profiles to avoid obstacles and clear terrain are calculated with one engine inoperative. The Climb profiles would have been calculated before takeoff for the Weight, Altitude & Temperature (WAT) at ADD on the day in question.
2) The extra thrust from having two engines operating more than offsets the extra drag from leaving the Flaps at the takeoff setting and leaving the Gear down. Basically, It's excess engine thrust that allows the airplane to climb.

Yes, you explained things, but I am not really convinced.
Just let me try again:
SOP - keep configuration, set average power, keep fixed pitch - is apparently designed to prevent going into an undesired mode, not for obstacle clearance. It will give you level flight with slight climb.
At the moment of airspeed disagree indication, the flight just rotated - it was very low, just above Vr, with gear down, in hot and high location.
Assuming plane instantly went into that fail safe mode - reduced thrust, fixed pitch - they will be flying parallel to the ground at their altitude of hundreds feet, with minimal terrain features and even tall trees at their level. If they did that and flown into the hill, everyone here would be crying about "airmanship"
So here comes "airmanship", aka deviation from the standard procedure - they need to maintain climb of at least - whatever it is for 737 with engine out, 1 or 2 degrees? That is not what airspeed disagree SOP would provide. Which means some of the following must be done to avoid CFIT: reducing drag, maintaining higher thrust than prescribed, maintaining higher pitch (IMHO least favorable option), to achieve certain truly failsafe situation.
Am I wrong in any of the above?
 
marcelh
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 10:33 am

morrisond wrote:
PixelFlight wrote:
morrisond wrote:
In hindsight given the existing state of Pilot training Boeing should have known better and not assumed that Pilots could handle a relatively simple Emergency (it's not as though the Rudder or Horizontal Tailplane fell off). But I don't think it rises to the state of Criminality. They made an assumption that was incorrect.

"simple Emergency" is certainly not appropriate for a so deadly new failure mode that take months to agree on the procedure to use to survive. The published EAD claim that the trim wheels can be used after the cutout switches without even a single word about the allowed speed to do that. There no word either about how to avoid the MCAS action without using the cutoff switches.

The state of criminality will be evaluated by the multiple legal actions that will be opened. The problem for Boeing is that there don't simply make an incorrect assumption while having put everything in place to catch it. There strong suggestions that Boeing was under stress to deliver a very hard promise and take decisions more to reach that promise than catching safety issue. This is at least what the legal cases will try to prove.


I totally agree on the legal issues.

On the taking months to decide on the procedure needed to survive - I think that only took about 9-10 days from the Lionair Crash on Oct 29 - to when Boeing Released the EAD on Nov 8 with the proper procedures - the crew just needed to fully understand that memo. I'm of the opinion they never did (based on their actions) which I pin right on ET.

If the crew didn't know that excessive speed was a bad thing and could affect the ability to control the aircraft that is a problem with training - it does not need to be pointed out in the EAD. Should the EAD also have said "Make sure the Engines are on?" or "Make sure you maintain airspeed above stall?"

And al those “pilots” are perfectly able to fly the NG.... Why did they screwed up big time flying the MAX?
 
kalvado
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 10:41 am

Chemist wrote:
kalvado wrote:
morrisond wrote:
I suspect Crew training standards were improving for quite some time on that graph along with more reliable safe designs. Crew training standards just seem to have taken a nosedive in the last 20 years.

You are still not answering the Question - Do you believe existing crew training standards are sufficient? What type of emergencies do you think they should they be able to handle if any at all?

Crew training standard, design parameters and risks converge to statistical number - probability for passenger to arrive in one piece. So far, typical crew training seems adequate for modern jets (A320 and later, 777, 737NG); ....


Asiana crashed a perfectly healthy 777 on a clear calm day due to training deficiencies and piloting errors.

Absolutely true. And thats why I said there is only that far training can take the numbers. You can train for errors, you cannot train out acute idiocy.
Technology and procedure gave them a lot of chances to see the mistake and avoid it. They knew - and actually tried, albeit too late, - that a go-around will save the day.
Would you assume that they never heard "don't try to salvage approach, if in doubt go around" and just needed another repeat of the same? Or if presented in another shape or form this would make a difference?
So I don't believe pilot training per se was the problem. Not in a simple way of "better classes, more sim sessions".
 
FluidFlow
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 11:41 am

nikeherc wrote:
FluidFlow wrote:

I think the biggest mistake was the goal from boeing that MAX=NG.

I am no Pilot, i am no engineer but I know quiet alot about fluiddynamics and in that regard MAX=NG is by no means right. They are two different aircraft.

To try to make them equal lead to the death of 350 people.

Traing the pilots for the NEW aircraft would have helped alot as it seems their training was good enough for the OLD NG as there are statistically way less accidents witj that aircraft so the pilots are good enough but the training was not enough to change to the new one.


I don't think that the goal was to make the MAX=NG. Clearly the goal was to make the Max better than the NG. A subsidiary goal was to make the Max fly and handle like the NG. There is nothing wrong with this. The problem was in the execution.


They definitely wanted to make it more efficient, the complete product seems to be worse than the NG as it is less safe.

They unfortunately did not make it handle the same Boeing only augmented it, on an aircraft that is grandfathered from a sixty-year-old concept.

In my opinion, the aircraft was too old for that step.

Morrisond listed nicely that incidents on the FBW aircrafts from Airbus only happened with elevator inputs and it was no problem to recover from it. MCAS does change trim significantly and that can crash aircrafts rather fast. In my opinion, the mixture of FBW feature on an ancient non FBW aircraft does not work and the MAX seems to prove that.

The fault must have happened during the design. (I don’t know how the design with Boeing went but here would be the chain on the stuff I worked on)

The designers improved the aerodynamics of the NG at the drawing board. Then they put the new engines in the only position that allowed enough clearing. A model (1:3 or 1:4) was built and cramped with sensors and put into the wind tunnel.
The collected data was used in a computer simulation and that gave the result that the aircraft was not certifiable under current regulations.

There were now two options:
1) Back to the drawing board, redesign the H-stab, or the nacelles, or the main landing gear, etc.), build another model and test it again in the wind tunnel. Then another simulation and see if the result is certifiable. This would have cost a lot and would have probably taken 6 to 24 months depending on the changes necessary and if the step hat to be repeated.
2) Use a software solution to compensate for the change in aerodynamics. Cheap and fast. That is also were the first deflection in the MCAS came from. Simulations are not perfect and during flight tests it seems that more trim was needed. Instead of making a proper risk analysis at this point and return to step 1) as the input was extreme they went with it and just hoped it will all be fine. Now in the new version they want to go back to the pre-flight-testing settings but that was not enough in the first place. Will be fun to see how they justify that.

We know now which route was taken. Long story short, it would have been cheaper to delay the aircraft by the time it would have taken to redesign.
 
morrisond
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 12:08 pm

PixelFlight wrote:
morrisond wrote:
kayik wrote:

The writer here implies that chances of a similar accident is zilch since there was no accident and the aircraft was not an A320.


Yes - but it was an Airbus 330 with a FBW system where it tried to put the plane in the ground.

ADIRU fault generating unbelievable, still unexplained, repetitive spike data without triggering any integrity test + FC algorithm design error that was never catch before because nobody was able to think that a such repetitive spike data could be possible in reality. The algorithm was corrected. This ADIRU was analyzed but never sent such repetitive spike data anymore, nobody known why. Safety assessment was evaluated and found ok.


Yes a systems problem put the A330 into a dive and the crew was able to save it - Good crew.
 
morrisond
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 12:11 pm

Jetty wrote:
morrisond wrote:
Yes it is. Basically no one is taking safety seriously enough.

You’ve made over 200 posts in this topic with exactly this assertion. Is it really necessary to repeat it whenever you have the chance? In the last few posts there’s even a streak with you writing 5 out of 7 posts in a row without adding something substantive to what anyone that follows this thread already knew about your stance. Your views are appreciated but please don’t see it as a requirement to respond to every post.


If people keep trying to assert there was no issues in training and it's all Boeing's fault - I'll keep posting.
 
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SomebodyInTLS
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 12:29 pm

morrisond wrote:
Jetty wrote:
morrisond wrote:
Yes it is. Basically no one is taking safety seriously enough.

You’ve made over 200 posts in this topic with exactly this assertion. Is it really necessary to repeat it whenever you have the chance? In the last few posts there’s even a streak with you writing 5 out of 7 posts in a row without adding something substantive to what anyone that follows this thread already knew about your stance. Your views are appreciated but please don’t see it as a requirement to respond to every post.


If people keep trying to assert there was no issues in training and it's all Boeing's fault - I'll keep posting.


The agenda speaks at last!
"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."
 
kalvado
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 12:44 pm

morrisond wrote:
PixelFlight wrote:
morrisond wrote:

Yes - but it was an Airbus 330 with a FBW system where it tried to put the plane in the ground.

ADIRU fault generating unbelievable, still unexplained, repetitive spike data without triggering any integrity test + FC algorithm design error that was never catch before because nobody was able to think that a such repetitive spike data could be possible in reality. The algorithm was corrected. This ADIRU was analyzed but never sent such repetitive spike data anymore, nobody known why. Safety assessment was evaluated and found ok.


Yes a systems problem put the A330 into a dive and the crew was able to save it - Good crew.

It happened twice in decades of Airbus FBW use in decades, and not in critical stages of flight. Good system design. Unlike.
 
morrisond
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 12:44 pm

zeke wrote:
morrisond wrote:
Yes - but it was an Airbus 330 with a FBW system where it tried to put the plane in the ground.


It didnt actually, it reduced the angle attack via an elevator input as it detected a stall, which the pilots were able to counter by putting in elevator input in the opposite direction. Any change in attitude at cruise speeds results in significant rates of climb or descent, hence the reason why TCAS events at high altitudes often result in passenger injuries, and the reason why Airbus developed the auto TCAS. Please remember the difference between elevator and stabilizer, MCAS dives the stabilizer.


Hi Zeke - Sorry I was thinking of Lufthansa 1829 in 2014

From AVHerald

"The Aviation Herald learned that the loss of altitude had been caused by two angle of attack sensors having frozen in their positions during climb at an angle, that caused the fly by wire protection to assume, the aircraft entered a stall while it climbed through FL310. The Alpha Protection activated forcing the aircraft to pitch down, which could not be corrected even by full back stick input. The crew eventually disconnected the related Air Data Units and was able to recover the aircraft."
 
morrisond
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 12:48 pm

SomebodyInTLS wrote:
morrisond wrote:
Jetty wrote:
You’ve made over 200 posts in this topic with exactly this assertion. Is it really necessary to repeat it whenever you have the chance? In the last few posts there’s even a streak with you writing 5 out of 7 posts in a row without adding something substantive to what anyone that follows this thread already knew about your stance. Your views are appreciated but please don’t see it as a requirement to respond to every post.


If people keep trying to assert there was no issues in training and it's all Boeing's fault - I'll keep posting.


The agenda speaks at last!


Yes - It's pretty simple - Blame to go around on all sides and if we don't look at all aspects of the crashes and think of improvements we can make in design, regulation and training that's a real shame.

Many on here seem to think that if you just put Boeing out of business the rest will go away.

But it won't as you can't design the perfect aircraft and parts fail(or freeze) - so you need well trained crews.
 
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zeke
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 1:21 pm

morrisond wrote:

Hi Zeke - Sorry I was thinking of Lufthansa 1829 in 2014

From AVHerald

"The Aviation Herald learned that the loss of altitude had been caused by two angle of attack sensors having frozen in their positions during climb at an angle, that caused the fly by wire protection to assume, the aircraft entered a stall while it climbed through FL310. The Alpha Protection activated forcing the aircraft to pitch down, which could not be corrected even by full back stick input. The crew eventually disconnected the related Air Data Units and was able to recover the aircraft."


Like most of your posts you posts about Airbus FBW going into an unrecoverable dive is highly inaccurate and not worthy of this site. I wish we could vote people to be banned from topics. The LH crew were able to maintain level by applying approximately half elevator input. Can you please stop posting inaccurate low quality posts that has nothing to do with the topic being discussed.

“The aircraft however continued to pitch down, inputs to counter the pitch down remained without effect. About 45 seconds after the nose down began the first officer alerted the captain who took control of the aircraft, that at this time had reached a rate of descent of 4000 feet per minute and a pitch of -3.5 degrees. The captain provided a maximum nose up input which caused the aircraft to pitch up again and the rate of descent decreased and the aircraft entered level flight.

The captain was able to maintain altitude by providing a continuous nose up input deflecting the side stick about 50% of its travel. The autopilot could not be engaged again, and a manual nose up trim was not possible.”

The crew ineffectively applied the ADR disagree QRH checklist (they stumbled around turning different things off instead of following the published procedure), and eventually got the aircraft out of normal law and continuous control inputs to maintain level were no longer required.
Human rights lawyers are "ambulance chasers of the very worst kind.'" - Sky News
 
morrisond
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 1:58 pm

zeke wrote:
morrisond wrote:

Hi Zeke - Sorry I was thinking of Lufthansa 1829 in 2014

From AVHerald

"The Aviation Herald learned that the loss of altitude had been caused by two angle of attack sensors having frozen in their positions during climb at an angle, that caused the fly by wire protection to assume, the aircraft entered a stall while it climbed through FL310. The Alpha Protection activated forcing the aircraft to pitch down, which could not be corrected even by full back stick input. The crew eventually disconnected the related Air Data Units and was able to recover the aircraft."


Like most of your posts you posts about Airbus FBW going into an unrecoverable dive is highly inaccurate and not worthy of this site. I wish we could vote people to be banned from topics. The LH crew were able to maintain level by applying approximately half elevator input. Can you please stop posting inaccurate low quality posts that has nothing to do with the topic being discussed.

“The aircraft however continued to pitch down, inputs to counter the pitch down remained without effect. About 45 seconds after the nose down began the first officer alerted the captain who took control of the aircraft, that at this time had reached a rate of descent of 4000 feet per minute and a pitch of -3.5 degrees. The captain provided a maximum nose up input which caused the aircraft to pitch up again and the rate of descent decreased and the aircraft entered level flight.

The captain was able to maintain altitude by providing a continuous nose up input deflecting the side stick about 50% of its travel. The autopilot could not be engaged again, and a manual nose up trim was not possible.”

The crew ineffectively applied the ADR disagree QRH checklist (they stumbled around turning different things off instead of following the published procedure), and eventually got the aircraft out of normal law and continuous control inputs to maintain level were no longer required.


If I implied it was unrecoverable that was not my intention - I did say the crews recovered it and did a good job. Those were words from AVHerald - not me. On the flight traces it looks like they retarded throttle (as the Mach Number is coming down as they Descend) which maybe is why the Captain was able to recover and the elevator became effective. Hard to tell though as no N1 traces.

And what do you think would have happened if they were were a few thousand feet above ground and didn't retard the throttle and left it at TOGA like on the ET flight?

I was just responding to a poster above basically saying FBW is the be all and end all - yes assuming the programming/software is perfect. If Boeing had put more robust Software in the MAX then we wouldn't be having this discussion.
 
OldAeroGuy
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 2:21 pm

kalvado wrote:
So here comes "airmanship", aka deviation from the standard procedure - they need to maintain climb of at least - whatever it is for 737 with engine out, 1 or 2 degrees? That is not what airspeed disagree SOP would provide. Which means some of the following must be done to avoid CFIT: reducing drag, maintaining higher thrust than prescribed, maintaining higher pitch (IMHO least favorable option), to achieve certain truly failsafe situation.
Am I wrong in any of the above?


Yes, you are wrong.

The basic of airmanship in this case are:

- Pitch
- Power
- Monitor Performance

The crew are not blind automations. The ET302 flight was in daylight and clear air. The terrain around the airport was known to the crew as it was their home airport. They had accelerated to 250 KIAS and were at 1500 AGL. At that point trees were not a problem and terrain was not a problem. So far, so good.

An important airmanship issue occurs at this point. There was a continuous stall warning and an "Airspeed Disagree".

The choices were:

- Land and find out why the stick shaker is going off
- Retract the flaps and continue the mission

Unfortunately, the ET302 crew chose the later.
Last edited by OldAeroGuy on Thu May 02, 2019 2:39 pm, edited 1 time in total.
Airplane design is easy, the difficulty is getting them to fly - Barnes Wallis
 
BigDaddy747
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 2:28 pm

What about the wings?
 
Exeiowa
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 2:36 pm

I work in chemical plant safety, as a point of reference.

Failures modes should be predictable (it was not predicted)

Failures should be notified (they turned them off)

Training should be provided to deal with the results (not deemed necessary)

Boeing should work on fixing the problem, check there is nothing else that was missed, and then work with customers about what the users of the equipment really need to know to operate it safely. This should not really be necessary to be spelled out.

In chemical safety everyone loves training as the solution to all, mainly because its cheap. However, the hierarchy shows that is your last point to address, you should work on the other ones even though they cost more. Mainly because you never quite know how people will react, will they catch it in time how will it manifest. I will put it this way, I dont want to have to be hands of hopping for a hero.
 
kalvado
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 2:41 pm

OldAeroGuy wrote:
kalvado wrote:
So here comes "airmanship", aka deviation from the standard procedure - they need to maintain climb of at least - whatever it is for 737 with engine out, 1 or 2 degrees? That is not what airspeed disagree SOP would provide. Which means some of the following must be done to avoid CFIT: reducing drag, maintaining higher thrust than prescribed, maintaining higher pitch (IMHO least favorable option), to achieve certain truly failsafe situation.
Am I wrong in any of the above?


Yes, you are wrong.

The basic of airmanship in this case are:

- Pitch
- Power
- Monitor Performance

The crew are not blind automations. The ET302 flight was in daylight and clear air. The terrain around the airport was known to the crew as it was their home airport. They elected to raise Flaps after accelerating to 250 KIAS and were at 1500 AGL. At that point trees were not a problem and terrain was not a problem.

The airmanship issue occurs at this point. The crew elected to raise the Flaps even though there was a continuous stall warning.

The choices were:

- Land and find out why the stick shaker is going off
- Retract the flaps and continue the mission

Unfortunately, the ET302 crew chose the later.


I am sorry, but you're cheating by making damning assumptions before analysis. Lets try talking without prejudice.
Regardless of further plans, ET302 crew would need to (1)climb out, (2)stabilize flight, (3)contact regional ATC. Whether vectors back to airport or to destination will be requested is another question, I don't believe they requested on or the other.
So lets consider first two steps - climb out, stabilize flight - as immediate tasks.
People blame the crew for not going to fail safe mode. Fail safe at altitude is not fail safe just above the ground. Am I right?
 
kalvado
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 2:53 pm

Exeiowa wrote:
I work in chemical plant safety, as a point of reference.

Failures modes should be predictable (it was not predicted)

Failures should be notified (they turned them off)

Training should be provided to deal with the results (not deemed necessary)

Boeing should work on fixing the problem, check there is nothing else that was missed, and then work with customers about what the users of the equipment really need to know to operate it safely. This should not really be necessary to be spelled out.

In chemical safety everyone loves training as the solution to all, mainly because its cheap. However, the hierarchy shows that is your last point to address, you should work on the other ones even though they cost more. Mainly because you never quite know how people will react, will they catch it in time how will it manifest. I will put it this way, I dont want to have to be hands of hopping for a hero.

One of the problems with such logic on this forum - there is enough people who have problems with finding pants accommodating their 12"... khm... airmanship, and who believe they can do everything in every possible situation...
 
Jamie514
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 3:01 pm

morrisond wrote:
Jamie514 wrote:
morrisond wrote:

I would bet Ethiopian Airlines is not as worried about getting sued as Boeing.


It seems they told the truth.

morrisond wrote:
From AVHerald

"On Apr 11th 2019 The Aviation Herald received a full copy of the Flight Operations Manual (FOM), Revision 18B released on Nov 30th 2018, which is currently being used by Ethiopian Airlines (verified in April 2019 to be current).


It may be a fantastic source of reporting, but any new information must be independently verified. It is impossible to do so with undisclosed sources. And it turns out it may not be accurate.

XRAYretired wrote:
From the PreliminaryReport.

1.16.2 OPERATION MANUAL EXTRACTS
1.16.2.1 ETHIOPIAN AIRLINES AIRCRAFT FLIGHT MANUAL (AFM)
A check of the AFM provided by Ethiopian Airlines showed that the airline had incorporated the revisions A180625 on November, 11 2018 required by Airworthiness Directive 2018-23-51. The two pages from the AFM are in Appendix .
1.16.2.2 FCOM BULLETIN ISSUED BY BOEING TO ETHIOPIAN AIRLINES An FCOM bulletin issued by Boeing to Ethiopian Airlines (ETH-12) regarding uncommanded nosedown stabilizer trim required Ethiopian Airlines to insert the bulletin in their B737MAX FCOM. The US Ops/hp technical advisors were provided an electronic copy of the Airline’s B737MAX FCOM, and the bulletin was found to be incorporated per Boeing directions.
The bulletin is shown in Appendix 4


Appendix 4 marked D6-27370-MAX-ETH February 21st 2019.


Thank you very much for this.


You've got it backwards - the AVHerald report came after the official Pre-lim report - they are basically saying the pre-lim report is full of s**t.

Nice partial quoting btw.


Please. You are now not only choosing to believe Boeing over Ethiopian. You are now choosing to believe unverifiable data from an unaccredited website over findings of the official investigation.

I will only grant that at some future time it may turn out that the training document AVHerald cites is real, but until that time, it is unproven conspiracy theory you are touting as a smoking gun here.

In post 97, I asked you:
Has AVHerald actually concluded that Pilot training provided by Ethiopian was the primary cause of the crash? Far as I could see, he only sees it as a POSSIBLE contributing factor, which I would agree with.


And instead of offering his conclusion, you offered unverifiable evidence.

Speaking of partial quoting, 5 paragraphs below what you think is the smoking gun training documents revelation, AVHerald did reach this conclusion,

Primary cause of the accident:
- MCAS activation based on a single faulty AoA sensor input without cross check or plausibility check of the incoming AoA value, which caused the stabilizer to reach a position that could no longer be compensated by elevator inputs

Primary contributing factors int the accident:

- A false AoA value, probably produced by the Air Data Reference unit rather than a mechanical fault, which activated the stick shaker and MCAS.
- aircraft systems not adhering to principles of Cockpit Resource Management CRM (MCAS, Stick Shaker, Air Data Reference Unit, AoA, Trim CUTOUT switches)

Possibly contributing factors into the accident:
- Corporate Culture within Boeing in designing aircraft
- Corporate Culture within FAA in certifying aircraft
- Corporate Culture in Ethiopian Airlines, which did not ensure their flight crew were fully aware of the implications of the LionAir Crash and the related EAD as well as Boeing and FAA approved emergency procedures
- Less than optimal crew performance, e.g. loss of situational awareness with respect to speed and thrust


You are using AVHerald to support your argument as if he was crusading it as the primary cause. It is in reality, the very bottom of his list. At the very top are MCAS, Boeing, FAA, Aircraft Systems.
 
XRAYretired
Posts: 615
Joined: Fri Mar 15, 2019 11:21 am

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 3:11 pm

OldAeroGuy wrote:
kalvado wrote:
So here comes "airmanship", aka deviation from the standard procedure - they need to maintain climb of at least - whatever it is for 737 with engine out, 1 or 2 degrees? That is not what airspeed disagree SOP would provide. Which means some of the following must be done to avoid CFIT: reducing drag, maintaining higher thrust than prescribed, maintaining higher pitch (IMHO least favorable option), to achieve certain truly failsafe situation.
Am I wrong in any of the above?


Yes, you are wrong.

The basic of airmanship in this case are:

- Pitch
- Power
- Monitor Performance

The crew are not blind automations. The ET302 flight was in daylight and clear air. The terrain around the airport was known to the crew as it was their home airport. They had accelerated to 250 KIAS and were at 1500 AGL. At that point trees were not a problem and terrain was not a problem. So far, so good.

An important airmanship issue occurs at this point. There was a continuous stall warning and an "Airspeed Disagree".

The choices were:

- Land and find out why the stick shaker is going off
- Retract the flaps and continue the mission

Unfortunately, the ET302 crew chose the later.


So, we have 4 crews on 3 continents over 8 years in similar circumstances who all react initially in pretty much the same way (including all retract flaps). Why do you think that would be?

Ray
 
FluidFlow
Posts: 287
Joined: Wed Apr 10, 2019 6:39 am

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 3:17 pm

morrisond wrote:
zeke wrote:
morrisond wrote:

Hi Zeke - Sorry I was thinking of Lufthansa 1829 in 2014

From AVHerald

"The Aviation Herald learned that the loss of altitude had been caused by two angle of attack sensors having frozen in their positions during climb at an angle, that caused the fly by wire protection to assume, the aircraft entered a stall while it climbed through FL310. The Alpha Protection activated forcing the aircraft to pitch down, which could not be corrected even by full back stick input. The crew eventually disconnected the related Air Data Units and was able to recover the aircraft."


Like most of your posts you posts about Airbus FBW going into an unrecoverable dive is highly inaccurate and not worthy of this site. I wish we could vote people to be banned from topics. The LH crew were able to maintain level by applying approximately half elevator input. Can you please stop posting inaccurate low quality posts that has nothing to do with the topic being discussed.

“The aircraft however continued to pitch down, inputs to counter the pitch down remained without effect. About 45 seconds after the nose down began the first officer alerted the captain who took control of the aircraft, that at this time had reached a rate of descent of 4000 feet per minute and a pitch of -3.5 degrees. The captain provided a maximum nose up input which caused the aircraft to pitch up again and the rate of descent decreased and the aircraft entered level flight.

The captain was able to maintain altitude by providing a continuous nose up input deflecting the side stick about 50% of its travel. The autopilot could not be engaged again, and a manual nose up trim was not possible.”

The crew ineffectively applied the ADR disagree QRH checklist (they stumbled around turning different things off instead of following the published procedure), and eventually got the aircraft out of normal law and continuous control inputs to maintain level were no longer required.


If I implied it was unrecoverable that was not my intention - I did say the crews recovered it and did a good job. Those were words from AVHerald - not me. On the flight traces it looks like they retarded throttle (as the Mach Number is coming down as they Descend) which maybe is why the Captain was able to recover and the elevator became effective. Hard to tell though as no N1 traces.

And what do you think would have happened if they were were a few thousand feet above ground and didn't retard the throttle and left it at TOGA like on the ET flight?

I was just responding to a poster above basically saying FBW is the be all and end all - yes assuming the programming/software is perfect. If Boeing had put more robust Software in the MAX then we wouldn't be having this discussion.


High velocity protection will pitch the aircraft up with up to 1.75g. Would be a funny thing when the computer fights itself. I guess it will end up in ditching normal law and either go into alternate law or direct law what actually would end up in solving the problem itself, if the pilots do not stall the aircraft afterwards.
 
User avatar
keesje
Posts: 13179
Joined: Thu Apr 12, 2001 2:08 am

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 3:29 pm

OldAeroGuy wrote:
kalvado wrote:
So here comes "airmanship", aka deviation from the standard procedure - they need to maintain climb of at least - whatever it is for 737 with engine out, 1 or 2 degrees? That is not what airspeed disagree SOP would provide. Which means some of the following must be done to avoid CFIT: reducing drag, maintaining higher thrust than prescribed, maintaining higher pitch (IMHO least favorable option), to achieve certain truly failsafe situation.
Am I wrong in any of the above?


Yes, you are wrong.

The basic of airmanship in this case are:

- Pitch
- Power
- Monitor Performance

The crew are not blind automations. The ET302 flight was in daylight and clear air. The terrain around the airport was known to the crew as it was their home airport. They had accelerated to 250 KIAS and were at 1500 AGL. At that point trees were not a problem and terrain was not a problem. So far, so good.

An important airmanship issue occurs at this point. There was a continuous stall warning and an "Airspeed Disagree".

The choices were:

- Land and find out why the stick shaker is going off
- Retract the flaps and continue the mission

Unfortunately, the ET302 crew chose the later.


First pilot priority is fly the aircraft. They were fighting to keep the nose up, going through emergency checks lists. Not sure what you are trying to suggest with "continue the mission". It's this kind of communication that makes people suspicious. Boeing suffers from it too. It's costing them billions.
"Never mistake motion for action." Ernest Hemingway
 
kalvado
Posts: 1996
Joined: Wed Mar 01, 2006 4:29 am

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 3:36 pm

keesje wrote:
OldAeroGuy wrote:
kalvado wrote:
So here comes "airmanship", aka deviation from the standard procedure - they need to maintain climb of at least - whatever it is for 737 with engine out, 1 or 2 degrees? That is not what airspeed disagree SOP would provide. Which means some of the following must be done to avoid CFIT: reducing drag, maintaining higher thrust than prescribed, maintaining higher pitch (IMHO least favorable option), to achieve certain truly failsafe situation.
Am I wrong in any of the above?


Yes, you are wrong.

The basic of airmanship in this case are:

- Pitch
- Power
- Monitor Performance

The crew are not blind automations. The ET302 flight was in daylight and clear air. The terrain around the airport was known to the crew as it was their home airport. They had accelerated to 250 KIAS and were at 1500 AGL. At that point trees were not a problem and terrain was not a problem. So far, so good.

An important airmanship issue occurs at this point. There was a continuous stall warning and an "Airspeed Disagree".

The choices were:

- Land and find out why the stick shaker is going off
- Retract the flaps and continue the mission

Unfortunately, the ET302 crew chose the later.


First pilot priority is fly the aircraft. They were fighting to keep the nose up, going through emergency checks lists. Not sure what you are trying to suggest with "continue the mission". It's this kind of communication that makes people suspicious. Boeing suffers from it too. It's costing them billions.

Slow down. We're talking about what happened before nose down.
Right after the rotation, crew got airspeed disagree message and stick shaker.
At that point opinions diverge. Some claim that pilots should have immediately applied standard procedure which would keep them safe. I am arguing that standard procedure was not applicable as it will not allow for safe flight that low off the ground, and pilots had to start deviating from that.
 
OldAeroGuy
Posts: 3886
Joined: Sun Dec 05, 2004 6:50 am

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 3:36 pm

kalvado wrote:
I am sorry, but you're cheating by making damning assumptions before analysis. Lets try talking without prejudice.
Regardless of further plans, ET302 crew would need to (1)climb out, (2)stabilize flight, (3)contact regional ATC. Whether vectors back to airport or to destination will be requested is another question, I don't believe they requested on or the other.
So lets consider first two steps - climb out, stabilize flight - as immediate tasks.
People blame the crew for not going to fail safe mode. Fail safe at altitude is not fail safe just above the ground. Am I right?


If we examine the ET302 behavior, we find they did not do what you are suggesting.

They did not stabilize the flight. Instead, they accelerated in level flight to Vmo before initiating a climb. Vmo is well beyond normal climb speed of around 280 KIAS. While this is may be understandable as they were dealing with inappropriate MCAS activity, allowing speed to increase to Vmo was a fundamental mistake. and 1500 AGL is not "just above the ground".

Once again, you are wrong.
Airplane design is easy, the difficulty is getting them to fly - Barnes Wallis
 
Chemist
Posts: 575
Joined: Tue Oct 20, 2015 4:46 am

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 3:43 pm

FluidFlow wrote:

They definitely wanted to make it more efficient, the complete product seems to be worse than the NG as it is less safe.

They unfortunately did not make it handle the same Boeing only augmented it, on an aircraft that is grandfathered from a sixty-year-old concept.

In my opinion, the aircraft was too old for that step.


Please explain how the age of the aircraft design had anything to do with whether you can augment handling on a new revision.
 
XRAYretired
Posts: 615
Joined: Fri Mar 15, 2019 11:21 am

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu May 02, 2019 3:47 pm

Stumbled across interesting article on embedded systems possibly of interest to others.

'5 Lessons to Learn from the Boeing 737 MAX Fiasco
Although it will be months before we have full reports about the 737 MAX crashes, we don’t have to wait to draw lessons from those incidents.'
https://www.designnews.com/electronics- ... 7532460732

Ray
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