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2175301
Posts: 1877
Joined: Wed May 16, 2007 11:19 am

Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 11:11 am

mjoelnir wrote:
It is still a fact that Mark Forkner took the fifth in regards to documents regarding his time at Boeing in the criminal Investigation that is going on.


It is also a fact that Mr Forkner no longer had direct access to the Boeing Documents as he no longer works there. He would have had to request them from Boeing, and the DOJ (and anyone else) could have requested them directly from Boeing.

Invoking the 5th Amendment does not indicate guilt - and in many cases is nothing more than legal maneuvering - which is all I see this to be.

The only potential legal liability of Mr. Forkner that I see is if he did not put his observations at the time into the internal Boeing flight and test reports; and then followed up to see if there was a resolution to the issue.

Have a great day,
 
clancy688
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 11:30 am

edu2703 wrote:
lowbank wrote:
Do not underestimate the fear of flying in the general public.


Well, the general public can barely differentiate a B737 from an A320


We're in the 21st century where there's an app for anything. And the information about which plane you'll be using is freely available on the internet. I don't doubt that within days of the max flying again, there'll be a handy website / app where you can simply enter your flight number, and it will tell you if you're flying with a MAX or not.
 
planecane
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 11:40 am

Amiga500 wrote:
planecane wrote:
I really hope you aren't a pilot. Use some common sense. If the same thing keeps happening over and over again and the thing that keeps happening is an abnormal amount of nose down trim it should be clear that there is a problem with the trim system.


OK, so now you are saying it should be possible to diagnose after several repeated MCAS interventions?

Right.

So if, say, the pilots on ET302 were to engage the cut-off switches after several MCAS activations - but then found they couldn't reverse the stabliser with the manual trim wheel due to adverse loading - so had to reengage the electric trim in an effort to get some authority on stabilizer...


They were not supposed to just flip the cutout switches. They were supposed to run the runaway stabilizer NNC as written which would have them get back in trim before cutting out the switches. I am running under the assumption that the limits placed on the electric trim on the MAX did not prevent them from getting back in trim. If it was limited in authority and prevented them from getting back in trim then there was nothing they could do except the "roller coaster" procedure to get manual trim to work.
 
planecane
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 11:45 am

FluidFlow wrote:
planecane wrote:
FluidFlow wrote:

The logical follow up for this is though, that electrical trim is still functioning and not the cause of the run away. This only leaves the options that actually manual trim does run away when electrical trim is not on (so switching off electrical trim is really counter-intuitive in that situation) or the computer that controls electric trim (that is active parallel to the thumb switches) is malfunctioning and is trimming but at this point it was not 100% clear to the pilots that with AP off there is actually a computer aided system (besides STS) working in the background that could malfunction (or better function as intended, to press the nose down no matter if it kills everyone as long as AoA is too high). It was probably known that MCAS was a thing but not how it works, where it is implemented and how it is shown and felt if it goes rogue. That would have been an item for difference training in a sim but yeah Boeing thought better hide it.


The fact that electric trim is still functioning does not indicate that it is not the cause of the runaway. In fact, the way the NNC is written, it seems that it would be expected for electric trim to be able to counter a runaway in many situations. The manual wheel/manual trim system has priority so the fact that the electric trim worked would indicate that the manual (non-electric) part of the system wasn't the likely cause.



In the electric trim regime I see 5 possible failures that lead to run away trim:

1. The manual electric trim inputs have a short or are stuck or any other failure
2. The actuator fails and just trims till the max/min
3. The wiring fails/shortcuts
4. The computer fails
5. The manual non-electric trim fails

Now how does this impact the pilot, or how is it felt:

1. The trim is continuous and can not be stopped if smacking the control column does not release the switches. Nothing can be done except hit the cut out switches
2. Will be a continuous trim that will not stop if you flick the thumb switches
3. same as 2.
4. This is actually the tricky part because the manual electric trim does still work and if activated will kill the signal from the computer because it has priority over the computer
5. This would be a death sentence because no matter what both ways of trimming would be tarnished and there would be no real way to use electric trim if manual is prioritized over electrical

Now for Point 4:

If the computer fails, or in case of MCAS actually does what it supposed to do (trim with unlimited authority no matter what as long as AoA>X) then it does not present itself as a runaway because:

1. Electric trim does still work and
2. After you did trim with electric trim there is no immediate restart of trim caused by the computer, there is a 5 second break. This actually means that the trim action is deliberate by the computer and not a malfunction.

The problem is that it was never stated that a false input from the AoA probe will lead to step-wise nose down trim.
The problem could also be a broken feel computer. At the end it is, with no knowledge of the engineering and function of the software, almost impossible to conclude that a broken AoA sensor leads to the computer deliberately apply step-wise nose down input.
The real problem seems to be that a broken AoA probe leads to a cascade of problems in the 737 without ever telling the pilot that the probe is broken. The trim did not run away or had a failure, all the trim inputs from the computer were legit and working as intended. From the aircraft perspective only a full nose down input was the solution to a problem that actually was not there.


The reason that NNCs exist is so that the pilots do not need to be diagnosing the cause of issues. They shouldn't be going through the troubleshooting steps that you have listed. Upon recognizing a runaway stabilizer (regardless of cause) they are supposed to follow the runaway stabilizer NNC. If that doesn't work, then they can move on to try on the fly troubleshooting.

As I have previously stated, IF the limits placed on the electric trim on the MAX prevented the pilots from getting back into trim using the thumb switches then there was nothing they could do to recover short of the roller coaster procedure if the forces were too great to turn the manual wheel.
 
WingsOfLove
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 11:46 am

Patrick KY on the 'dealignment' of EASA from FAA certifications

http://jdasolutions.aero/blog/global-ai ... on-course/
 
Noshow
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 11:48 am

They were supposed to run the runaway stabilizer NNC as written which would have them get back in trim before cutting out the switches. I am running under the assumption that the limits placed on the electric trim on the MAX did not prevent them from getting back in trim. If it was limited in authority and prevented them from getting back in trim then there was nothing they could do except the "roller coaster" procedure to get manual trim to work.


They were not "supposed" to do anything. Boeing had hoped without telling them they would run some entirely different checklist for runaway trim that would have been one single runaway and not interrupted repeated trim movements for no reason known to the pilots.
 
Amiga500
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 12:02 pm

planecane wrote:
They were not supposed to just flip the cutout switches. They were supposed to run the runaway stabilizer NNC as written which would have them get back in trim before cutting out the switches. I am running under the assumption that the limits placed on the electric trim on the MAX did not prevent them from getting back in trim. If it was limited in authority and prevented them from getting back in trim then there was nothing they could do except the "roller coaster" procedure to get manual trim to work.


I would agree with that assumption. Unlikely the electric motor could not torque the jackscrew enough (but not impossible I suppose).

I believe they did several manual (switch based) corrections to trim before they hit the cutouts.

Unfortunately MCAS over-rode their inputs prior to them hitting the cutouts. I anticipate the delay between their retrim and the cutout was likely due to information overload and the pilots trying to diagnose multiple alerts at once.


I would expect (and hope) that one of the major findings the out of date warning systems within the 737 which do not sufficiently isolate the problem but instead presented a cacophony of alerts each vying for "I'm most critical" status. While this may not change the MAX - I hope it does change any grandfathering certifications in future.
 
FluidFlow
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 12:04 pm

planecane wrote:
FluidFlow wrote:
planecane wrote:

The fact that electric trim is still functioning does not indicate that it is not the cause of the runaway. In fact, the way the NNC is written, it seems that it would be expected for electric trim to be able to counter a runaway in many situations. The manual wheel/manual trim system has priority so the fact that the electric trim worked would indicate that the manual (non-electric) part of the system wasn't the likely cause.



In the electric trim regime I see 5 possible failures that lead to run away trim:

1. The manual electric trim inputs have a short or are stuck or any other failure
2. The actuator fails and just trims till the max/min
3. The wiring fails/shortcuts
4. The computer fails
5. The manual non-electric trim fails

Now how does this impact the pilot, or how is it felt:

1. The trim is continuous and can not be stopped if smacking the control column does not release the switches. Nothing can be done except hit the cut out switches
2. Will be a continuous trim that will not stop if you flick the thumb switches
3. same as 2.
4. This is actually the tricky part because the manual electric trim does still work and if activated will kill the signal from the computer because it has priority over the computer
5. This would be a death sentence because no matter what both ways of trimming would be tarnished and there would be no real way to use electric trim if manual is prioritized over electrical

Now for Point 4:

If the computer fails, or in case of MCAS actually does what it supposed to do (trim with unlimited authority no matter what as long as AoA>X) then it does not present itself as a runaway because:

1. Electric trim does still work and
2. After you did trim with electric trim there is no immediate restart of trim caused by the computer, there is a 5 second break. This actually means that the trim action is deliberate by the computer and not a malfunction.

The problem is that it was never stated that a false input from the AoA probe will lead to step-wise nose down trim.
The problem could also be a broken feel computer. At the end it is, with no knowledge of the engineering and function of the software, almost impossible to conclude that a broken AoA sensor leads to the computer deliberately apply step-wise nose down input.
The real problem seems to be that a broken AoA probe leads to a cascade of problems in the 737 without ever telling the pilot that the probe is broken. The trim did not run away or had a failure, all the trim inputs from the computer were legit and working as intended. From the aircraft perspective only a full nose down input was the solution to a problem that actually was not there.


The reason that NNCs exist is so that the pilots do not need to be diagnosing the cause of issues. They shouldn't be going through the troubleshooting steps that you have listed. Upon recognizing a runaway stabilizer (regardless of cause) they are supposed to follow the runaway stabilizer NNC. If that doesn't work, then they can move on to try on the fly troubleshooting.

As I have previously stated, IF the limits placed on the electric trim on the MAX prevented the pilots from getting back into trim using the thumb switches then there was nothing they could do to recover short of the roller coaster procedure if the forces were too great to turn the manual wheel.


The problem is, it is not a run away stabilizer trim, because there is no malfunction in the trim system or the computer. The trim inputs from the computer were deliberate, had a fixed duration, a fixed deflection, a given activation interval and a single purpose: to reduce AoA. It was also possible to stop the trim inputs by the computer, by overriding them with manual electric trim and I guess also by manually turning the trim wheels. Nothing here points to a run away stabilizer. Nothing in the whole system happened unintended except it was the classical crap input = crap output. This should have been addressed by Boeing as catastrophic because the system was and maybe still is not able to vet the input parameters. So crap input will still lead to crap output.
 
mjoelnir
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 12:04 pm

2175301 wrote:
mjoelnir wrote:
It is still a fact that Mark Forkner took the fifth in regards to documents regarding his time at Boeing in the criminal Investigation that is going on.


It is also a fact that Mr Forkner no longer had direct access to the Boeing Documents as he no longer works there. He would have had to request them from Boeing, and the DOJ (and anyone else) could have requested them directly from Boeing.

Invoking the 5th Amendment does not indicate guilt - and in many cases is nothing more than legal maneuvering - which is all I see this to be.

The only potential legal liability of Mr. Forkner that I see is if he did not put his observations at the time into the internal Boeing flight and test reports; and then followed up to see if there was a resolution to the issue.

Have a great day,


If you do not have the information, you do not need to plead the fifth, you can simply state, that you do not have the requested information. Mark Forkner was one of the persons responsible for the drive to convince the FAA to accept leaving MCAS out of the manuals.
 
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klm617
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 12:24 pm

morrisond wrote:
PixelFlight wrote:
morrisond wrote:

Even I wouldn't go that far other than to rewrite your sentence as "But given the massive number of established facts actually available that point to the management, design, certification and airmanship issues the MAX deserved to be grounded and the whole system looked at to ensure we can make air travel as safe as possible"

Notice that you have to semantically move the "airmanship" word from the original quote to make your argument not impossible. :stirthepot:

Did you get the fact that only the 737-8/9 MAX is actually grounded, and that without it, the 737-600/700/800/900 NG pilots worldwide managed to provides one of the lowest fatal crash rates per million flights in the commercial aircraft industry ?

MAX != NG, not because of the pilots.


Pilots seem to have a hard time manually flying the NG when the Automation breaks as well - see ET409 - and it's not the pilots - it's the training system/airlines penny pinching just as much as Boeing is at fault for penny pinching/in pursuit of profit.


Exactly it's the culture at these airlines where the issue lies. I'd much rather fly on a MAX8 than I would Ethiopian or Lionair.
the truth does matter, guys. too bad it's often quite subjective. the truth is beyond the mere facts and figures. it's beyond good and bad, right and wrong...
 
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par13del
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 12:25 pm

asdf wrote:
Amiga500 wrote:
More to the point -
1. if the trim wheel spins for 3 seconds.
2. then the crew intervene and correct with trim switches.
3. MCAS cuts out for ~5 seconds (IIRC), so stabilizer stops trimming
4. which is then not in any way similar to how runaway stabilizer presents itself.


from my knowledge .... you can not expect an airline crew to react within 4 seconds with the appropiate action
not even to a memory item

If we are talking about response time, how much time is required when the AP disconnects? To my knowledge, none of the frames currently flying has a AP warning when data get's corrupted like a countdown clock etc., it just disconnects immediately.
 
planecane
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 12:34 pm

par13del wrote:
asdf wrote:
Amiga500 wrote:
More to the point -
1. if the trim wheel spins for 3 seconds.
2. then the crew intervene and correct with trim switches.
3. MCAS cuts out for ~5 seconds (IIRC), so stabilizer stops trimming
4. which is then not in any way similar to how runaway stabilizer presents itself.


from my knowledge .... you can not expect an airline crew to react within 4 seconds with the appropiate action
not even to a memory item

If we are talking about response time, how much time is required when the AP disconnects? To my knowledge, none of the frames currently flying has a AP warning when data get's corrupted like a countdown clock etc., it just disconnects immediately.

Or an engine failure on takeoff. They'd better be responding very quickly.
 
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EA CO AS
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 12:35 pm

mjoelnir wrote:
2175301 wrote:
mjoelnir wrote:
It is still a fact that Mark Forkner took the fifth in regards to documents regarding his time at Boeing in the criminal Investigation that is going on.


It is also a fact that Mr Forkner no longer had direct access to the Boeing Documents as he no longer works there. He would have had to request them from Boeing, and the DOJ (and anyone else) could have requested them directly from Boeing.

Invoking the 5th Amendment does not indicate guilt - and in many cases is nothing more than legal maneuvering - which is all I see this to be.

The only potential legal liability of Mr. Forkner that I see is if he did not put his observations at the time into the internal Boeing flight and test reports; and then followed up to see if there was a resolution to the issue.

Have a great day,


If you do not have the information, you do not need to plead the fifth, you can simply state, that you do not have the requested information. Mark Forkner was one of the persons responsible for the drive to convince the FAA to accept leaving MCAS out of the manuals.



New reporting from the Seattle Times:

https://www.seattletimes.com/business/b ... -messages/
"In this present crisis, government is not the solution to our problem - government IS the problem." - Ronald Reagan

Comments made here are my own and are not intended to represent the official position of Alaska Air Group
 
estorilm
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 12:40 pm

This got buried in one of the original crash threads - but what was the verdict on some of the classic pilots chiming in about elevator forces being overcome by h-stab forces beyond a certain deflection? Where essentially the elevator became a servo tab and would actually inhibit movement of the h-stab, and vise-versa? Additionally the forces basically made manual movement of the trim wheels almost impossible (and that was with the larger trim wheels).

A MX friend of mine is in denial about this entire thing, thinks the plane is fine and that both of the "3rd world crews" crashed the planes into the ground. I tried explaining the sequence of events, lack of FCOM mention in first crash and correct training/action in 2nd crash, but no dice. He said part of MX is to attach force devices to the control surfaces to emulate max aerodynamic pressures and test trim, deflection, etc operation. Basically regardless of what the plane did, they could have saved it. I know this is BS based on the crash transcripts, but is anyone familiar with this procedure? I'm sure it works for normal testing, but I highly doubt it's able to emulate a max-trimmed h-stab fighting an opposite-deflected elevator. That could only be done with airflow correct?
 
estorilm
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 12:42 pm

EA CO AS wrote:
mjoelnir wrote:
2175301 wrote:

It is also a fact that Mr Forkner no longer had direct access to the Boeing Documents as he no longer works there. He would have had to request them from Boeing, and the DOJ (and anyone else) could have requested them directly from Boeing.

Invoking the 5th Amendment does not indicate guilt - and in many cases is nothing more than legal maneuvering - which is all I see this to be.

The only potential legal liability of Mr. Forkner that I see is if he did not put his observations at the time into the internal Boeing flight and test reports; and then followed up to see if there was a resolution to the issue.

Have a great day,


If you do not have the information, you do not need to plead the fifth, you can simply state, that you do not have the requested information. Mark Forkner was one of the persons responsible for the drive to convince the FAA to accept leaving MCAS out of the manuals.



New reporting from the Seattle Times:

https://www.seattletimes.com/business/b ... -messages/

"..even though the simulator faults made it seem so..."

Wow, stated as fact already. They really got out in front of this one early didn't they?

Considering these are professionals who are used to this - sim fault or not, they were clearly surprised/shocked at some of the behavior here. If it was a typical sim fault or whatever I'd expect a different reaction.
 
kalvado
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 12:45 pm

mjoelnir wrote:
It is still a fact that Mark Forkner took the fifth in regards to documents regarding his time at Boeing in the criminal Investigation that is going on.

Which I see pretty strange. Employee is not supposed to be in possession of any such documents after separation, not at commercial company.
The only plausible scenario I see is that feds were looking for communications via personal e-mail or something along those lines. Is it possible that some Boeing - FAA communications occurred off-record?
 
planecane
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 12:52 pm

mjoelnir wrote:
2175301 wrote:
mjoelnir wrote:
It is still a fact that Mark Forkner took the fifth in regards to documents regarding his time at Boeing in the criminal Investigation that is going on.


It is also a fact that Mr Forkner no longer had direct access to the Boeing Documents as he no longer works there. He would have had to request them from Boeing, and the DOJ (and anyone else) could have requested them directly from Boeing.

Invoking the 5th Amendment does not indicate guilt - and in many cases is nothing more than legal maneuvering - which is all I see this to be.

The only potential legal liability of Mr. Forkner that I see is if he did not put his observations at the time into the internal Boeing flight and test reports; and then followed up to see if there was a resolution to the issue.

Have a great day,


If you do not have the information, you do not need to plead the fifth, you can simply state, that you do not have the requested information. Mark Forkner was one of the persons responsible for the drive to convince the FAA to accept leaving MCAS out of the manuals.

I don't believe you are from the USA. This is not the case at all. You need to plead the fifth so that you don't say anything that can be used by the State to convict you of a crime. If you just say you don't have the information and later they find some document you forgot about they can prosecute for perjury.
 
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gatibosgru
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 12:57 pm

Going back and reading the Q1 thread is quite enlightening. Some people were so sure the grounding was unfounded and wouldn't last, and here we are in mid Oct 2019.
@DadCelo
 
morrisond
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 12:57 pm

sgrow787 wrote:
Despite Dominic's previous credible reporting, has he now been bought off?

You don't use words like "egregious" unless you're sure what you're looking at. Particularly if what you're looking at points to the safety of the aircraft.


So now Boeing has bought off the New York Times, The Washington Post and the Seattle times?

Yeah - right....
 
morrisond
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 1:00 pm

PixelFlight wrote:
morrisond wrote:
PixelFlight wrote:
Notice that you have to semantically move the "airmanship" word from the original quote to make your argument not impossible. :stirthepot:

Did you get the fact that only the 737-8/9 MAX is actually grounded, and that without it, the 737-600/700/800/900 NG pilots worldwide managed to provides one of the lowest fatal crash rates per million flights in the commercial aircraft industry ?

MAX != NG, not because of the pilots.


Pilots seem to have a hard time manually flying the NG when the Automation breaks as well - see ET409 - and it's not the pilots - it's the training system/airlines penny pinching just as much as Boeing is at fault for penny pinching/in pursuit of profit.

Simply false: ET409 did not have "Automation breaks".


Sorry - you are right - I should have just said - inability to fly manually without the Automation.
 
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PixelFlight
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 1:01 pm

klm617 wrote:
morrisond wrote:
PixelFlight wrote:
Notice that you have to semantically move the "airmanship" word from the original quote to make your argument not impossible. :stirthepot:

Did you get the fact that only the 737-8/9 MAX is actually grounded, and that without it, the 737-600/700/800/900 NG pilots worldwide managed to provides one of the lowest fatal crash rates per million flights in the commercial aircraft industry ?

MAX != NG, not because of the pilots.


Pilots seem to have a hard time manually flying the NG when the Automation breaks as well - see ET409 - and it's not the pilots - it's the training system/airlines penny pinching just as much as Boeing is at fault for penny pinching/in pursuit of profit.


Exactly it's the culture at these airlines where the issue lies. I'd much rather fly on a MAX8 than I would Ethiopian or Lionair.
:crazy: :banghead:
Not like if there are the only airlines with 737 issues https://en.wikipedia.org/wiki/List_of_a ... Boeing_737
:stirthepot: 737-8 MAX: "For all speeds higher than 220 Kts and trim set at a value of 2.5 units, the difficulity level of turning the manual trim wheel was level A (trim wheel not movable)." :stirthepot:
 
morrisond
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 1:03 pm

FluidFlow wrote:
planecane wrote:
asdf wrote:

what would be a long, but "normal" automatic trim wheel operation?
five seconds?
six seconds?

Going off of my own simulator session and videos on YouTube, it is normally short bursts of one or two seconds on autopilot.

In manual flight it would have only been expected if it was STS. I don't know the answer for that system but it certainly doesn't keep trimming to the point where the stick force becomes very high. I can only assume it would be similar. Based on the report plots with flaps still deployed any automatic trim was short bursts which would be consistent with that.

Also, we've seen reference to the FAA expecting pilot response to a runaway to be 3 seconds. Therefore, it is a logical conclusion that over 3 seconds of continuous trim is not normal.

The combination of long bursts of trim combined with the great increase in stick force should have indicated that something was wrong with the trim system. Since it obviously wasn't a jammed stabilizer the only other logical conclusion is a runaway.


The logical follow up for this is though, that electrical trim is still functioning and not the cause of the run away. This only leaves the options that actually manual trim does run away when electrical trim is not on (so switching off electrical trim is really counter-intuitive in that situation) or the computer that controls electric trim (that is active parallel to the thumb switches) is malfunctioning and is trimming but at this point it was not 100% clear to the pilots that with AP off there is actually a computer aided system (besides STS) working in the background that could malfunction (or better function as intended, to press the nose down no matter if it kills everyone as long as AoA is too high). It was probably known that MCAS was a thing but not how it works, where it is implemented and how it is shown and felt if it goes rogue. That would have been an item for difference training in a sim but yeah Boeing thought better hide it.


Why would not assume it was an STS problem?

Easy solution - turn it off and fly manually.
 
morrisond
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 1:06 pm

asdf wrote:
Amiga500 wrote:
More to the point -
1. if the trim wheel spins for 3 seconds.
2. then the crew intervene and correct with trim switches.
3. MCAS cuts out for ~5 seconds (IIRC), so stabilizer stops trimming
4. which is then not in any way similar to how runaway stabilizer presents itself.


from my knowledge .... you can not expect an airline crew to react within 4 seconds with the appropiate action
not even to a memory item

if trim spin is normal
trim spin up to 3 seconds

at the 4th second the crew has to
- rethink if its really been three seconds or more
- give it another second (maybe we didnt realized..)
- determine if something else is not OK with the plane
- check back with the other pilot that something is going on with the trim
- deside if there is a somewhat normal explanation to it or if it is a situation to intervene
- grab the collumne and pull back to stop trim
- remember the ipad course a year ago that pulling back the colume does not stop trimming
- try the cut-out switches and find out that they are renamed and regrouped now on another position

...

IF at this stage at least 4 seconds have passed by, then the MCAS trim has stopped in the meantime ...

maybe a lot to think about what has happend
but nothing to do if you follow the procedures and you are not a clairvoyant


Please show in the Lionair or ET flights they only had 4 seconds to save the plane. They had minutes to figure it out.
 
Amiga500
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 1:07 pm

estorilm wrote:
He said part of MX is to attach force devices to the control surfaces to emulate max aerodynamic pressures and test trim, deflection, etc operation.


Load testing the servos/hyraulics/hinges to a load specified within the AMM is not the ultimate load that the unit may experience in flight.

That is quite obvious - as after an ultimate limit load event - the aircraft will have to undergo at least a partial inspection for damage.


So its impossible for any post-maintenance test to simulate the ultimate flight loads.
 
Amiga500
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 1:08 pm

morrisond wrote:
Why would not assume it was an STS problem?

Easy solution - turn it off and fly manually.



The first problem they had to worry about was the stall warning.

Funnily enough, it would take precedence over any movement of the trim wheel.
 
morrisond
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 1:09 pm

Amiga500 wrote:
planecane wrote:
I really hope you aren't a pilot. Use some common sense. If the same thing keeps happening over and over again and the thing that keeps happening is an abnormal amount of nose down trim it should be clear that there is a problem with the trim system.


OK, so now you are saying it should be possible to diagnose after several repeated MCAS interventions?

Right.

So if, say, the pilots on ET302 were to engage the cut-off switches after several MCAS activations - but then found they couldn't reverse the stabliser with the manual trim wheel due to adverse loading - so had to reengage the electric trim in an effort to get some authority on stabilizer...


As they were flying at full thrust at over Vmo - well above normal operating speed and the speed limit below 10,000' - it's as bad as no thrust and below stall speed - the trim wheel isn't going to help much there either.
 
Amiga500
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 1:16 pm

morrisond wrote:
As they were flying at full thrust at over Vmo - well above normal operating speed and the speed limit below 10,000' - it's as bad as no thrust and below stall speed - the trim wheel isn't going to help much there either.


You keep on ignoring the stall warning they were receiving.

It is likely they had doubts over their airspeed indicators, so probably were attempting thrust and AoA flight... and failing miserably due to the unwanted intervention of MCAS.
 
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 1:17 pm

Amiga500 wrote:
estorilm wrote:
He said part of MX is to attach force devices to the control surfaces to emulate max aerodynamic pressures and test trim, deflection, etc operation.


Load testing the servos/hyraulics/hinges to a load specified within the AMM is not the ultimate load that the unit may experience in flight.

That is quite obvious - as after an ultimate limit load event - the aircraft will have to undergo at least a partial inspection for damage.


So its impossible for any post-maintenance test to simulate the ultimate flight loads.

I meant specifically his implication that such tests would prove that the pilots would always be able to overcome any possible loads they'd see in the cockpit (either elevator or trim) regardless of h-stab or trim position and aircraft AoA / speed. From those old classic pilot stories, that was certainly not the case, and some had said it's almost a guarantee that the same problem could be a contributing factor in these incidents (maybe more since the trim wheels are significantly smaller vs. classics).
 
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 1:30 pm

morrisond wrote:
FluidFlow wrote:
planecane wrote:
Going off of my own simulator session and videos on YouTube, it is normally short bursts of one or two seconds on autopilot.

In manual flight it would have only been expected if it was STS. I don't know the answer for that system but it certainly doesn't keep trimming to the point where the stick force becomes very high. I can only assume it would be similar. Based on the report plots with flaps still deployed any automatic trim was short bursts which would be consistent with that.

Also, we've seen reference to the FAA expecting pilot response to a runaway to be 3 seconds. Therefore, it is a logical conclusion that over 3 seconds of continuous trim is not normal.

The combination of long bursts of trim combined with the great increase in stick force should have indicated that something was wrong with the trim system. Since it obviously wasn't a jammed stabilizer the only other logical conclusion is a runaway.


The logical follow up for this is though, that electrical trim is still functioning and not the cause of the run away. This only leaves the options that actually manual trim does run away when electrical trim is not on (so switching off electrical trim is really counter-intuitive in that situation) or the computer that controls electric trim (that is active parallel to the thumb switches) is malfunctioning and is trimming but at this point it was not 100% clear to the pilots that with AP off there is actually a computer aided system (besides STS) working in the background that could malfunction (or better function as intended, to press the nose down no matter if it kills everyone as long as AoA is too high). It was probably known that MCAS was a thing but not how it works, where it is implemented and how it is shown and felt if it goes rogue. That would have been an item for difference training in a sim but yeah Boeing thought better hide it.


Why would not assume it was an STS problem?

Easy solution - turn it off and fly manually.


How do you turn STS off?

How does an STS problem unfold?

Oh and there is a speed trim light as well as a warning, so STS failure could be excluded.
 
LondonAero
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 1:37 pm

What do we think they mean by "steady progress on the second software update" from the statement today-> Doesn't sound like it is solver (or close to solved)? "Software Updates & Flight Testing: We updated the Maneuvering Characteristics Augmentation Software (MCAS) on the MAX by adding three additional layers of protection that will prevent accidents like these from ever happening again. To date, we have conducted more than 800 test and production flights with the updated software, totaling more than 1,500 hours. The company is making steady progress on the second software update announced in June for additional flight control computer redundancy. Some 445 participants from more than 140 customers and regulators around the globe, including the FAA, have participated in simulator sessions to experience the proposed MCAS software update. Just last week the company successfully conducted a dry-run of a certification flight test"
 
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 1:55 pm

The 'expose' of the two pilots and their messages was an inadvertent but classic 'red herring'. That is, it was a side issue on building the software for the simulator, not the actual MAX. The original exposes did not make this clear, and in factual error said it was a MAX issue. And the inadvertent 'lie' seems to be a timeline issue. Forkner had told the FAA that MCAS had certain characteristic at one point, and some time later learned it had been changed. It is not known whether he corrected himself and so advised the FAA or even if he was required to.

Res pleading the 5th. If I have this correctly, you cannot partially answer a question by giving evidence that supports your position, and then plead the 5th on evidence against you. You need to be ready to 'tell the truth, the whole truth, and nothing but the truth', or just shut up about the whole thing.
Last edited by frmrCapCadet on Tue Oct 22, 2019 2:00 pm, edited 1 time in total.
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morrisond
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 1:59 pm

Amiga500 wrote:
morrisond wrote:
As they were flying at full thrust at over Vmo - well above normal operating speed and the speed limit below 10,000' - it's as bad as no thrust and below stall speed - the trim wheel isn't going to help much there either.


You keep on ignoring the stall warning they were receiving.

It is likely they had doubts over their airspeed indicators, so probably were attempting thrust and AoA flight... and failing miserably due to the unwanted intervention of MCAS.


They had two working airspeed indicators. A proper crosscheck would have told them the stall warning was false.
 
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 2:03 pm

FluidFlow wrote:
morrisond wrote:
FluidFlow wrote:

The logical follow up for this is though, that electrical trim is still functioning and not the cause of the run away. This only leaves the options that actually manual trim does run away when electrical trim is not on (so switching off electrical trim is really counter-intuitive in that situation) or the computer that controls electric trim (that is active parallel to the thumb switches) is malfunctioning and is trimming but at this point it was not 100% clear to the pilots that with AP off there is actually a computer aided system (besides STS) working in the background that could malfunction (or better function as intended, to press the nose down no matter if it kills everyone as long as AoA is too high). It was probably known that MCAS was a thing but not how it works, where it is implemented and how it is shown and felt if it goes rogue. That would have been an item for difference training in a sim but yeah Boeing thought better hide it.


Why would not assume it was an STS problem?

Easy solution - turn it off and fly manually.


How do you turn STS off?

How does an STS problem unfold?

Oh and there is a speed trim light as well as a warning, so STS failure could be excluded.


Turn off the trim switches.

It's an trim problem - it can fail many ways - you can't have a procedure explaining every possible failure mode as it will take too long to diagnose - if something isn't behaving as you expect (Trim System) turn it off.

It's a failure - maybe the the light isn't working or the sensor has failed - hit the switches and take control of the aircraft.
 
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 2:04 pm

keesje wrote:
.
:arrow: I'm shocked on how the 3 yr old, incoherent half drunk Forkner text messages let to a steep drop in Boeing stock price, but the expert JATR report two weeks ago did not.

Baseless emotions seem to drive stock price, while stock price steers salaries / company strategy. :worried:

Shocked, shocked you say?

Yes, emotion does drive markets.

Also, I think a lot of the JATR conclusions were already factored in to the stock price by the time the report was published.

Many people paying attention to this issue had already said "The only way the MAX tragedy could have happened is if Boeing did 'X'" and the JATR report served to confirm 'X' in many different cases.

The stuff said in the Forkner texts served as confirmation of a WaPo piece that came out this spring that presumably was based on the info that Boeing turned over to FBI / DOJ, but was so scandalous it was bound to get attention.

Yet today even ST is saying Forkner's texts were likely about a buggy version of the sim, go figure.
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 2:11 pm

LondonAero wrote:
What do we think they mean by "steady progress on the second software update" from the statement today-> Doesn't sound like it is solver (or close to solved)? "Software Updates & Flight Testing: We updated the Maneuvering Characteristics Augmentation Software (MCAS) on the MAX by adding three additional layers of protection that will prevent accidents like these from ever happening again. To date, we have conducted more than 800 test and production flights with the updated software, totaling more than 1,500 hours. The company is making steady progress on the second software update announced in June for additional flight control computer redundancy. Some 445 participants from more than 140 customers and regulators around the globe, including the FAA, have participated in simulator sessions to experience the proposed MCAS software update. Just last week the company successfully conducted a dry-run of a certification flight test"

I think you refer to Boeing's recap ahead of the earnings call posted by Leeham ( https://leehamnews.com/2019/10/22/boein ... ings-call/ ) and others.

"Steady Progress" to me means they aren't ready to declare victory yet, either for technical or political reasons, not sure which.

WSJ ( https://www.wsj.com/articles/friction-b ... 1570527001 ) reported there were some contention between Boeing and EASA on how to test the "additional flight control computer redundancy" so perhaps that's why they can't claim victory yet.

Note that this statement does not contain an announcement of the cancellation of the MAX program.
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FluidFlow
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 2:12 pm

morrisond wrote:
FluidFlow wrote:
morrisond wrote:

Why would not assume it was an STS problem?

Easy solution - turn it off and fly manually.


How do you turn STS off?

How does an STS problem unfold?

Oh and there is a speed trim light as well as a warning, so STS failure could be excluded.


Turn off the trim switches.

It's an trim problem - it can fail many ways - you can't have a procedure explaining every possible failure mode as it will take too long to diagnose - if something isn't behaving as you expect (Trim System) turn it off.

It's a failure - maybe the the light isn't working or the sensor has failed - hit the switches and take control of the aircraft.


First and foremost: Trim did not fail though, it did exactly what it was intended to do. It did what the engineers at Boeing made it to do.

And if you would switch off every automation at the moment it does something unexpected you would have to switch of STS all the time. Automation is there to assist you so you first check what causes the problem and you do not prematurely switch it off you run a diagnosis first, that's why the flip the cut out switches comes at the end of the check list not as item Nr. 1.

If it would have been safer on the 737 to train the pilots to hit the cut out switches first on the Max because the risk is different than on the NG, ok i accept that. Just stupid that Boeing saw it differently with the training requirement.

We can definitely agree on the fact more training is needed right? So we go ahead with the MAX as the first model to need a new training regime. What about 1500h minimum flying in a sim? And from now on every successive new aircraft will need that amount of training before you get the type rating.

We can not apply it to already in service aircraft that would ground too much and ruin the economy but we could start from now on with every model that needs (re)certification.
 
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 2:23 pm

EA CO AS wrote:
New reporting from the Seattle Times:

https://www.seattletimes.com/business/b ... -messages/

Lots of meat for the techies to chew on in this report:

(Aerospace engineer and former fighter pilot Bjorn) Ferhm believes that what happened in Forkner’s simulator on Nov. 15 was just another simulator discrepancy, something wrong with the coding.

He notes that Forkner says he was flying level at a low 4,000 feet altitude and at 230 knots. This is an appropriate speed for that altitude and he calculates the angle of attack could have been no more than about 5 degrees.

The design of MCAS would have required at least twice as high an angle to be triggered. And to get to such an angle, Forkner would have had to pull back the controls creating a severe force of around 2 Gs, the sort of extreme maneuver an airline pilot would never execute unless in a sudden emergency like pulling up to avoid a mountain.

Fehrm said that it’s clear from the chat Forkner wasn’t trying any such extreme maneuver, and so when he complains about MCAS kicking in, he’s referring to a crazy activation in the simulator that isn’t behaving as it would in a real airplane.

And:

Fehrm has harshly criticized Boeing’s original design of MCAS and says that he has “a real problem with Boeing’s culture.”

“I’m all for criticizing when it’s due,” he said. “But you have to be fair.”

Seems Bjorn is targeting this thread, lol.
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TropicalSky
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 2:24 pm

Looks like the FAA has started its review
https://www.reuters.com/article/us-ethi ... X11MM?il=0
 
morrisond
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 2:27 pm

FluidFlow wrote:
morrisond wrote:
FluidFlow wrote:

How do you turn STS off?

How does an STS problem unfold?

Oh and there is a speed trim light as well as a warning, so STS failure could be excluded.


Turn off the trim switches.

It's an trim problem - it can fail many ways - you can't have a procedure explaining every possible failure mode as it will take too long to diagnose - if something isn't behaving as you expect (Trim System) turn it off.

It's a failure - maybe the the light isn't working or the sensor has failed - hit the switches and take control of the aircraft.


First and foremost: Trim did not fail though, it did exactly what it was intended to do. It did what the engineers at Boeing made it to do.

And if you would switch off every automation at the moment it does something unexpected you would have to switch of STS all the time. Automation is there to assist you so you first check what causes the problem and you do not prematurely switch it off you run a diagnosis first, that's why the flip the cut out switches comes at the end of the check list not as item Nr. 1.

If it would have been safer on the 737 to train the pilots to hit the cut out switches first on the Max because the risk is different than on the NG, ok i accept that. Just stupid that Boeing saw it differently with the training requirement.

We can definitely agree on the fact more training is needed right? So we go ahead with the MAX as the first model to need a new training regime. What about 1500h minimum flying in a sim? And from now on every successive new aircraft will need that amount of training before you get the type rating.

We can not apply it to already in service aircraft that would ground too much and ruin the economy but we could start from now on with every model that needs (re)certification.


I totally second the 1,500 Hour requirement - with at least a few hundred in an actual aircraft and recurring training as well.

Having 200 hours and being put into a 737 is insane.
 
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 2:30 pm

TropicalSky wrote:
Looks like the FAA has started its review
https://www.reuters.com/article/us-ethi ... X11MM?il=0


"WASHINGTON (Reuters) - Boeing Co (BA.N) is making progress toward getting its 737 MAX aircraft in the air again but the U.S. Federal Aviation Administration (FAA) will need at least several more weeks for review, FAA Administrator Steve Dickson said on Tuesday.

Dickson said at a conference of air traffic controllers in Washington that the agency had received the “final software load” and “complete system description” of revisions to the plane, which was grounded in March after two fatal crashes."
 
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 2:31 pm

TropicalSky wrote:
Looks like the FAA has started its review
https://www.reuters.com/article/us-ethi ... X11MM?il=0

Mark October 22nd on your calendars:

Dickson said at a conference of air traffic controllers in Washington that the agency had received the “final software load” and “complete system description” of revisions to the plane, which was grounded in March after two fatal crashes.

Yet:

“It is going to be several more weeks before we go through all of that part of the process,” Dickson said. “We’ve got considerable work to do.”

If all goes well "mid Q4" will be missed by a few weeks, but global ungrounding in early 2020 is a plausible outcome given various recent statements.
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LondonAero
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 2:44 pm

Revelation wrote:
LondonAero wrote:
What do we think they mean by "steady progress on the second software update" from the statement today-> Doesn't sound like it is solver (or close to solved)? "Software Updates & Flight Testing: We updated the Maneuvering Characteristics Augmentation Software (MCAS) on the MAX by adding three additional layers of protection that will prevent accidents like these from ever happening again. To date, we have conducted more than 800 test and production flights with the updated software, totaling more than 1,500 hours. The company is making steady progress on the second software update announced in June for additional flight control computer redundancy. Some 445 participants from more than 140 customers and regulators around the globe, including the FAA, have participated in simulator sessions to experience the proposed MCAS software update. Just last week the company successfully conducted a dry-run of a certification flight test"

I think you refer to Boeing's recap ahead of the earnings call posted by Leeham ( https://leehamnews.com/2019/10/22/boein ... ings-call/ ) and others.

"Steady Progress" to me means they aren't ready to declare victory yet, either for technical or political reasons, not sure which.

WSJ ( https://www.wsj.com/articles/friction-b ... 1570527001 ) reported there were some contention between Boeing and EASA on how to test the "additional flight control computer redundancy" so perhaps that's why they can't claim victory yet.

Note that this statement does not contain an announcement of the cancellation of the MAX program.


Funny how they are not willing to declare victory yet on the Second Software Update but they are willing to declare victory on the MCAS fix (they use past tense)?
 
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 2:48 pm

LondonAero wrote:
Funny how they are not willing to declare victory yet on the Second Software Update but they are willing to declare victory on the MCAS fix (they use past tense)?

Yet we now know they just gave the whole package (software and documentation) to FAA, which adds more weight to the idea that there may be some testing aspect that Boeing and EASA are still working on resolving.
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LondonAero
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 2:51 pm

Revelation wrote:
LondonAero wrote:
Funny how they are not willing to declare victory yet on the Second Software Update but they are willing to declare victory on the MCAS fix (they use past tense)?

Yet we now know they just gave the whole package (software and documentation) to FAA, which adds more weight to the idea that there may be some testing aspect that Boeing and EASA are still working on resolving.


Thanks. You mean to say that it appears that at least on the face of it the FAA is ok with the second software fix but that EASA is still having some problems (which is why they didnt say it was complete yet)? They wouldnt submit it all to the FAA unless they had initial sign off from the FAA that is was ok?
 
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 3:02 pm

morrisond wrote:
They had two working airspeed indicators. A proper crosscheck would have told them the stall warning was false.


Do we know that for sure?

If a bird wiped out the AoA vane, then its not beyond the realms another bird wiped out the pitot tube on that side.
 
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 3:12 pm

morrisond wrote:
They had two working airspeed indicators. A proper crosscheck would have told them the stall warning was false.


näh

they had two different airspeeds indicated
they did NOT knew which one was correct

i do not know if that NNC of the QRH is correct because someone here in the thread mentioned his QRH looks different (but he didnt tell what it looks like)

NNC of the QRH you reference

7 Refer to the Flight With Unreliable Airspeed table in the Performance Inflight chapter and set the pitch attitude and thrust setting for the current airplane configuration and phase of flight.
8 When in trim and stabilized, cross check the captain, first officer and standby airspeed indicators. An airspeed indication that differs by more than 20 knots or 0.03 Mach from the airspeed shown in the table should be considered unreliable.
9 Choose one:
Reliable airspeed indication can be determined:
Use the most reliable airspeed source for the remainder of the flight.
Go to step 10
Reliable airspeed indication can not be determined:
Go to step 12
10 Flight director switch (reliable side) . . . . . . . .ON
11 Autopilot (reliable side) . . . . . . . . . . . . . .Engage
12 Set pitch attitude and thrust from the Flight With Unreliable Airspeed table in the Performance Inflight chapter for the airplane configuration and phase of flight, as needed.

(Performance section)
General General - Flight With Unreliable Airspeed Flight With Unreliable Airspeed/ Turbulent Air Penetration Altitude and/or vertical speed indications may also be unreliable.
Climb (280/.76) Flaps Up, Set Max Climb Thrust


thats what the ET guys did
 
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 3:18 pm

morrisond wrote:
As they were flying at full thrust at over Vmo - well above normal operating speed and the speed limit below 10,000' - it's as bad as no thrust and below stall speed - the trim wheel isn't going to help much there either.

You still don't get the fact that Vmo is just an arbitrary safety margin below the much higher design speed. The trim wheels must be usable up to the design speed, not just up to Vmo. And the difficulty to move the wheels was also probably linked to the extreme miss-trim induced by the MCAS. There are still the question why the pilots can't easily fully neutralize the stab trim (i have proposed two responses).
:stirthepot: 737-8 MAX: "For all speeds higher than 220 Kts and trim set at a value of 2.5 units, the difficulity level of turning the manual trim wheel was level A (trim wheel not movable)." :stirthepot:
 
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 3:30 pm

LondonAero wrote:
Thanks. You mean to say that it appears that at least on the face of it the FAA is ok with the second software fix but that EASA is still having some problems (which is why they didnt say it was complete yet)? They wouldnt submit it all to the FAA unless they had initial sign off from the FAA that is was ok?

My read of the the article and the highlighted points. The FAA head is admitting on 22nd Oct 2019 that they the FAA has received the final software load from Boeing along with manuals with descriptions / revisions etc etc.
The head of the FAA is saying that it will take them a few weeks to review the submission, I suggest this is where we can pick apart the time line.
Based on rumours and leaks, the FAA has been involved in some of the test flights, the FAA has been involved in the resolution process, it was the FAA not Boeing who introduced new parameters in June (bit flip) when the initial fix to MCAS was submitted. So if those are accurate, why would it take the professionals at the FAA several weeks to review items that they provided to Boeing for resolution, are they attempting to identify whether Boeing fixed other items rather than just those required by the FAA and EASA?
Do they have additional items they want Boeing to correct but were waiting until they got the latest updates to provide them to Boeing?
The politicians are now involved, and the scrutiny is now on the FAA as well, to some degree, they have been getting a free ride on the Hill not by EASA and others.
 
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 3:33 pm

LondonAero wrote:
Revelation wrote:
LondonAero wrote:
Funny how they are not willing to declare victory yet on the Second Software Update but they are willing to declare victory on the MCAS fix (they use past tense)?

Yet we now know they just gave the whole package (software and documentation) to FAA, which adds more weight to the idea that there may be some testing aspect that Boeing and EASA are still working on resolving.


Thanks. You mean to say that it appears that at least on the face of it the FAA is ok with the second software fix but that EASA is still having some problems (which is why they didnt say it was complete yet)? They wouldnt submit it all to the FAA unless they had initial sign off from the FAA that is was ok?

The WSJ article I linked said there is some contention between Boeign and EASA with regard to testing the second fix.

So, yes, I think it could be the case that Boeing submitted the package to FAA expecting FAA to be happy with the testing and with EASA still in the unresolved state.

Why? FAA is the one that certified the plane, so making FAA happy is first and foremost, resolving EASA concerns is important but second.

Also, Boeing is releasing quarterly results on Wednesday and after the Friday/Monday plummet in stock value Boeing just has to show progress, even if this means upsetting EASA a bit.

EASA probably won't be happy, but probably will understand that Boeing needs to put FAA first and needs to show progress.

EASA also still holds veto power over EU flights so their concerns will need to be addressed one way or the other.
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Tue Oct 22, 2019 3:33 pm

Nice to see Boeing on track, hopefully the FAA is fast and the MAX returns to the skies in November.

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