BoeingGuy
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 4:46 pm

ArgentoSystems wrote:
BoeingGuy wrote:

It was a supplier error. I’m familiar with the issue. The Display supplier incorrectly tied activation of the AOA Disagree to the AOA Display.


Wow. See, I don't care. If I buy stuff form Boeing, it is responsible for every component they get from others. If what you are saying is correct, they f*up incoming component testing.


Considering that what I’m saying is also being reported in the media, it’s correct.
 
OldAeroGuy
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 5:06 pm

PixelFlight wrote:
OldAeroGuy wrote:
At 5:39:22, autopilot was selected. The left stick shaker was active and Boeing procedure says do not select autopilot with an active stick shaker
[...]
At 5:39:45, the Captain asked the FO to retract Flaps. Boeing procedure says do not retract Flaps with an active stick shaker. The left stick shaker was active.

As an engineer, I would like to analyze with you why the 737-8 MAX allow to make actions that diverge from the Boeing procedures. The two stick shakers are trivial discrete signals that can easily be used to prevent selecting autopilot and to prevent retracting the flaps. This is really basic wiring and logic. Why the pilots are still allowed to do so ?


I suspect the reasons are something along these lines:

Implementation for inhibiting the autopilot would be fairly easy. The stick shaker signal is electrical (from the AoA's) and so is the autopilot switch. I suspect the reason for not inhibiting the autopilot during stick shaker is to make a point about the situation. Preventing a stall requires pilot awareness and action. The pilot must take action to prevent a stall. Don't think that engaging the autopilot will solve the situation. Plus, an autopilot malfunction may be the reason you're in the low energy situation to begin with.

Flap retraction inhibition would be more difficult. While the stick shaker signal is electrical, flap actuation is mechanical (the flap handle and cables) and hydraulic (valves and motors/linear actuators). Integrating the stick shaker signal into normal flap operation could create a new failure mode that could cause more nuisance Flap operation failures.

Happy to discuss though.
Airplane design is easy, the difficulty is getting them to fly - Barnes Wallis
 
OldAeroGuy
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 5:27 pm

Jamie514 wrote:
OldAeroGuy wrote:
All three MAX crews elected to retract Flaps with an active stick shaker. This is contrary to the published Boeing procedure.

If the three crews were not focused on completing their planned missions, why would they have retracted the Flaps?


Why before knowing the outcome of the investigation are you in such a rush to presume things that have not been offered as fact. What in the dynamic cockpit environment the pilots were facing makes you think abandoning the checklist was a mistake of rote procedure?


I'm only commenting on the published incident/accident reports.

At the time of Flap retraction, the only unusual cockpit environment element was the stick shaker, "Airspeed Disagree" and "Altitude Disagree". Boeing says don't retract Flaps with an active stick shaker. All three MAX crews did so.

Are these disputable facts?
Airplane design is easy, the difficulty is getting them to fly - Barnes Wallis
 
Jamie514
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 5:53 pm

OldAeroGuy wrote:
Jamie514 wrote:
OldAeroGuy wrote:
All three MAX crews elected to retract Flaps with an active stick shaker. This is contrary to the published Boeing procedure.

If the three crews were not focused on completing their planned missions, why would they have retracted the Flaps?


Why before knowing the outcome of the investigation are you in such a rush to presume things that have not been offered as fact. What in the dynamic cockpit environment the pilots were facing makes you think abandoning the checklist was a mistake of rote procedure?


I'm only commenting on the published incident/accident reports.

At the time of Flap retraction, the only unusual cockpit environment element was the stick shaker, "Airspeed Disagree" and "Altitude Disagree". Boeing says don't retract Flaps with an active stick shaker. All three MAX crews did so.

Are these disputable facts?


Are the facts available complete enough to reach conclusions about crew intention like you did?
 
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PixelFlight
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 6:12 pm

OldAeroGuy wrote:
Implementation for inhibiting the autopilot would be fairly easy. The stick shaker signal is electrical (from the AoA's) and so is the autopilot switch. I suspect the reason for not inhibiting the autopilot during stick shaker is to make a point about the situation. Preventing a stall requires pilot awareness and action. The pilot must take action to prevent a stall. Don't think that engaging the autopilot will solve the situation. Plus, an autopilot malfunction may be the reason you're in the low energy situation to begin with.

I don't understand how not preventing to select the autopilot when the stick shaker is active allow to make a point about the situation. Can you explain in more details please ?
I agree that a stall require pilot awareness and action. Now imagine that the pilots makes the observation that the aircraft is obviously not in a stall. Should there follow the stall procedure ?

OldAeroGuy wrote:
Flap retraction inhibition would be more difficult. While the stick shaker signal is electrical, flap actuation is mechanical (the flap handle and cables) and hydraulic (valves and motors/linear actuators). Integrating the stick shaker signal into normal flap operation could create a new failure mode that could cause more nuisance Flap operation failures.

Wow! I didn't realize before how incredibly old are the mechanical flaps command design on the 737-8 MAX. Electric flaps command was developed almost 4 decades ago on the A310. For the 737-8 MAX, it look a bit like the pilots have to learn more than the engineers to compensate the very old design. But regardless of the design, the same question as before raise to me: if the pilots observe that this is not a stall, should there blindly apply the procedure ?
 
c933103
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 6:31 pm

http://news.carnoc.com/list/492/492389.html

Shanghai Airlines said they are going to move their 737 Max to inland China starting from today as the hot, humid and typhoon season is coming to Shanghai soon.
When no other countries around the world is going to militarily stop China and its subordinate fom abusing its citizens within its national boundary, it is unreasonable to expect those abuse can be countered with purely peaceful means.
 
MrBretz
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 6:33 pm

For those of you who think AI is just around the corner, I recall a statement made by an MIT professor who taught AI. He said something like “they say AI is just around the corner. I think it will always be just around the corner.”
 
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7BOEING7
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 6:37 pm

PixelFlight wrote:
Wow! I didn't realize before how incredibly old are the mechanical flaps command design on the 737-8 MAX. Electric flaps command was developed almost 4 decades ago on the A310. For the 737-8 MAX, it look a bit like the pilots have to learn more than the engineers to compensate the very old design.


The point is it's a proven design, lots of spares and there is nothing to learn if you've been flying older model 737's, for both the pilots and the mechanics. And realistically from a pilot's standpoint how much do you need to learn about how to move a flap handle?
 
morrisond
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 6:38 pm

MrBretz wrote:
For those of you who think AI is just around the corner, I recall a statement made by an MIT professor who taught AI. He said something like “they say AI is just around the corner. I think it will always be just around the corner.”



I think real AI is still a good 10 years away - and then another 10 before it finds it's way into a cockpit to replace a human pilot.

Until then we need well trained pilots to cover for the engineers when they screw up or parts fail.
 
c933103
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 6:52 pm

MrBretz wrote:
For those of you who think AI is just around the corner, I recall a statement made by an MIT professor who taught AI. He said something like “they say AI is just around the corner. I think it will always be just around the corner.”

I agree that statement because many people have very high expectation on what an "AI" should be able to do and also overestimated a lot that what sort of ability an "AI" need to reach to do various different tasks. In reality that dream-like AI would never come in next few centuries, yet we will see more and more roles being done but machines and automation instead, and we won't say they are done by AI.
When no other countries around the world is going to militarily stop China and its subordinate fom abusing its citizens within its national boundary, it is unreasonable to expect those abuse can be countered with purely peaceful means.
 
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PW100
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 7:04 pm

Absynth wrote:
https://www.nytimes.com/2019/05/05/business/boeing-737-max-warning-light.html

After discovering the lapse in 2017, Boeing performed an internal review and determined that the lack of a working warning light “did not adversely impact airplane safety or operation,” it said in its statement.


Only after the crash of Lion Air Flight 610 last October did Boeing discuss the matter with the F.A.A. The company then conducted another review and again found the missing alert did not pose a safety threat, and told the F.A.A. as much.


let me get this straight...the Lion Air plane crashes because of a malfunctioning AoA sensor, and they still do not deem it necessary to correct their mistake of having the disagree light disabled? An alert for a sensor failure that caused the crash that should be working? Not only that, but they don't inform the airliners about a critical feature missing, that just caused a crash killing 189 people?

I found the Seattle Times article today already shocking to read. But this is just surreal.


It seems quite unlikley that this "warning light" would have prevented these accidents, as there was no training or anything else linking such light to MCAS. Heck, before the Lionair accident, MCAS was unknown to the complete 737 pilot community. After that, the significance of AoA disagree (or failure) to MCAS was still pretty much unknown, and also it was not universally known to MAX pilots that MCAS was fed of one single AoA sensor.

Boeing may have made a lot of mistakes on the MCAS, but the AoA disagree ommittance is fairly low on the list of significance with respect to both accidents.
Immigration officer: "What's the purpose of your visit to the USA?" Spotter: "Shooting airliners with my Canon!"
 
morrisond
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 7:08 pm

I found this quote on another forum and it made my draw drop. Maybe the ET crew never did extend the handle..

" I recently had an opportunity to fly with FO who was relatively new to the 737. During our trip, we discussed a number of issues that had come out of the recent MAX crashes. During this conversation, he confessed that before these accidents, he did not even know the stab trim wheel had a stowable handle and had never been trained in its use. Think about that for a moment. Also consider that a freshly-minted 737 Captain would have received the exact same training."
 
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PW100
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 7:09 pm

rheinwaldner wrote:
OldAeroGuy wrote:
With continuous stick shaker, all the MAX crews elected to continue their missions with continuous stick shaker.

This is wrong. The crews of both crashed MAXes wanted to return.
E.g. here is just one source.
Why do you push wrong information?


The crew that decided to continue to destination - desptite the continuous stick shaker - landed successfully. Both crews that decided to return did not live to tell . . .
Immigration officer: "What's the purpose of your visit to the USA?" Spotter: "Shooting airliners with my Canon!"
 
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PW100
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 7:16 pm

OldAeroGuy wrote:
rheinwaldner wrote:
OldAeroGuy wrote:
With continuous stick shaker, all the MAX crews elected to continue their missions with continuous stick shaker.

This is wrong. The crews of both crashed MAXes wanted to return.
E.g. here is just one source.
Why do you push wrong information?


All three MAX crews elected to retract Flaps with an active stick shaker. This is contrary to the published Boeing procedure.
If the three crews were not focused on completing their planned missions, why would they have retracted the Flaps?
For JT043, after STAB TRIM was deactivated, the planned flight was completed with the left stick shaker active.
For ET302, at 5:39:06, the FO reported to ATC that they were climbing to FL320. The stick shaker was active.
At 5:39:22, autopilot was selected. The left stick shaker was active and Boeing procedure says do not select autopilot with an active stick shaker
At 5:39:42, Level Change was selected to FL320. The left stick shaker was active.
At 5:39:45, the Captain asked the FO to retract Flaps. Boeing procedure says do not retract Flaps with an active stick shaker. The left stick shaker was active.
At 5:39:55, the autopilot disengaged. The left stick shaker was active.
At 5:39:57, the Captain asked the FO to maintain runway heading as they were having control issues as the autopilot was disconnected. The left stick shaker was active.
The above actions indicate that the ET302 was focused on continuing their mission with an active stick shaker.
At 5:40:00, MCAS began to pitch the airplane nose down. The left stick shaker was active.
At 5:42:10, after struggling with trim due to MCAS activity, the crew contacted ATC with a request for a return to land. This is the request your source cited.

https://www.flightradar24.com/blog/wp-c ... -ET302.pdf

While you are correct in saying that ET302 did request a return to land, they only did so after taking actions contrary to Boeing procedure and attempting to climb to a cruise altitude.
With stick shaker after liftoff, the correct actions would have been to leave the Flaps at the Takeoff setting and request a return to land without trying to climb to FL320.


Could the ET crew be forgiven for not following said procedure, when only one stick shaker was going off, when they determined that the stick shaker going off must have been false?

As you wrote earlier, the published procedure does not include such provisions. Some woud argue that this exactly is the reason why we have pilots: to make these sort of decisions and determine that such procedure may not not applicable to the specific situation in hand? Don't you think it would be premature at this stage to hold that against the crew, when we don't understand for sure why they choose not to follow said procedure?
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PW100
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 7:21 pm

morrisond wrote:
I found this quote on another forum and it made my draw drop. Maybe the ET crew never did extend the handle..

" I recently had an opportunity to fly with FO who was relatively new to the 737. During our trip, we discussed a number of issues that had come out of the recent MAX crashes. During this conversation, he confessed that before these accidents, he did not even know the stab trim wheel had a stowable handle and had never been trained in its use. Think about that for a moment. Also consider that a freshly-minted 737 Captain would have received the exact same training."


It certainly would be so. If this has been established as a FACT, rather than hearsay.
I surely hope that the investigation team will dig deep into this (well, at least the NTSB side of the team . . . ).

OTOH, it would be equally disturbing if it was established that the manual trim wheel would be too hard to turn by hand after MCAS activation . . .
Immigration officer: "What's the purpose of your visit to the USA?" Spotter: "Shooting airliners with my Canon!"
 
Absynth
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 7:29 pm

morrisond wrote:
MrBretz wrote:
For those of you who think AI is just around the corner, I recall a statement made by an MIT professor who taught AI. He said something like “they say AI is just around the corner. I think it will always be just around the corner.”


I think real AI is still a good 10 years away - and then another 10 before it finds it's way into a cockpit to replace a human pilot.

Until then we need well trained pilots to cover for the engineers when they screw up or parts fail.


Seeing how Boeing effed up a relatively simple software control system I'd rather stay home then board a Boeing designed AI flight control.
 
kalvado
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 7:30 pm

PW100 wrote:
rheinwaldner wrote:
OldAeroGuy wrote:
With continuous stick shaker, all the MAX crews elected to continue their missions with continuous stick shaker.

This is wrong. The crews of both crashed MAXes wanted to return.
E.g. here is just one source.
Why do you push wrong information?


The crew that decided to continue to destination - desptite the continuous stick shaker - landed successfully. Both crews that decided to return did not live to tell . . .

As someone who argued on this topic a lot:
@OldAeroGuy has a reasonably solid argument that flaps shouldn't be raised in that situation, and doing so means crew was planning on further unreasonable things like completing the flight as scheduled..
I find this argument to be at least 50/50 convincing, though last statement is strongly spiced by "Boeing makes great planes, too bad monkeys cannot fly those planes!" agenda. But you will not be able to break (or fully confirm) that logic without more information than we have today (which is not a lot), and possibly only pilots could tell what was on their mind, which may or may not be in CVR logs.
But I have to admit there is a pretty reasonable logic flow there. I wouldn't take that argument as "beyond reasonable doubt", though.
 
rj777
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 7:34 pm

I wonder if any of this is going to affect the 777X Certification and/or pilot training
 
rheinwaldner
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 7:40 pm

OldAeroGuy wrote:
rheinwaldner wrote:
OldAeroGuy wrote:
With continuous stick shaker, all the MAX crews elected to continue their missions with continuous stick shaker.

This is wrong. The crews of both crashed MAXes wanted to return.
E.g. here is just one source.
Why do you push wrong information?


All three MAX crews elected to retract Flaps with an active stick shaker.

Stop right here, please. You talked about continuing the mission. And me too. Not about raising flaps. They did not elect to continue the mission. You go beyond published known facts if you claim otherwise.

We can discuss about flaps separately if you like.

I think, they raised the flaps because after about a minute the PFD looked similar like this or even worse (with speed even deeper in the red area):
Image

Would you keep flying with flaps if the PFD would look like this?

I do not say, that it was not wrong according to Boeings procedures to raise the flaps. It was wrong.

I do say, that the decision to raise the flaps is not wrong IMO if the PFD looks like shown above (or with speed even much deeper in the red area, as they actually had). Would they not have risked to tear the flaps apart if they would not have raised them at the speeds they had?
Many things are difficult, all things are possible!
 
morrisond
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 7:43 pm

rheinwaldner wrote:
OldAeroGuy wrote:
rheinwaldner wrote:
This is wrong. The crews of both crashed MAXes wanted to return.
E.g. here is just one source.
Why do you push wrong information?


All three MAX crews elected to retract Flaps with an active stick shaker.

Stop right here, please. You talked about continuing the mission. And me too. Not about raising flaps. They did not elect to continue the mission. You go beyond published known facts if you claim otherwise.

We can discuss about flaps separately if you like.

I think, they raised the flaps because after about a minute the PFD looked similar like this or even worse (with speed even deeper in the red area):
Image

Would you keep flying with flaps if the PFD would look like this?

I do not say, that it was not wrong according to Boeings procedures to raise the flaps. It was wrong.

I do say, that the decision to raise the flaps is not wrong IMO if the PFD looks like shown above (or with speed even much deeper in the red area, as they actually had). Would they not have risked to tear the flaps apart if they would not have raised them at the speeds they had?


The logical thing would have been to pull the thrust back if they were going too fast - it's as bad as going too slow.
 
OldAeroGuy
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 7:50 pm

PW100 wrote:
OldAeroGuy wrote:
rheinwaldner wrote:
This is wrong. The crews of both crashed MAXes wanted to return.
E.g. here is just one source.
Why do you push wrong information?


All three MAX crews elected to retract Flaps with an active stick shaker. This is contrary to the published Boeing procedure.
If the three crews were not focused on completing their planned missions, why would they have retracted the Flaps?
For JT043, after STAB TRIM was deactivated, the planned flight was completed with the left stick shaker active.
For ET302, at 5:39:06, the FO reported to ATC that they were climbing to FL320. The stick shaker was active.
At 5:39:22, autopilot was selected. The left stick shaker was active and Boeing procedure says do not select autopilot with an active stick shaker
At 5:39:42, Level Change was selected to FL320. The left stick shaker was active.
At 5:39:45, the Captain asked the FO to retract Flaps. Boeing procedure says do not retract Flaps with an active stick shaker. The left stick shaker was active.
At 5:39:55, the autopilot disengaged. The left stick shaker was active.
At 5:39:57, the Captain asked the FO to maintain runway heading as they were having control issues as the autopilot was disconnected. The left stick shaker was active.
The above actions indicate that the ET302 was focused on continuing their mission with an active stick shaker.
At 5:40:00, MCAS began to pitch the airplane nose down. The left stick shaker was active.
At 5:42:10, after struggling with trim due to MCAS activity, the crew contacted ATC with a request for a return to land. This is the request your source cited.

https://www.flightradar24.com/blog/wp-c ... -ET302.pdf

While you are correct in saying that ET302 did request a return to land, they only did so after taking actions contrary to Boeing procedure and attempting to climb to a cruise altitude.
With stick shaker after liftoff, the correct actions would have been to leave the Flaps at the Takeoff setting and request a return to land without trying to climb to FL320.


Could the ET crew be forgiven for not following said procedure, when only one stick shaker was going off, when they determined that the stick shaker going off must have been false?

As you wrote earlier, the published procedure does not include such provisions. Some woud argue that this exactly is the reason why we have pilots: to make these sort of decisions and determine that such procedure may not not applicable to the specific situation in hand? Don't you think it would be premature at this stage to hold that against the crew, when we don't understand for sure why they choose not to follow said procedure?


There are good reasons the procedures are written the way they are. I've written about this previously. The point is, the crew do not know the state of their airplane. They only know a stick shaker is going off.

Starting with the 737 NG, 737's have a system for detecting leading edge devices being out of position or missing.

If a leading edge slat is missing or skewed, the stick shaker schedule will default to the Flaps up schedule. (Visit 7BOEING7's profile picture to see what a skewed slat looks like.) If the Flaps are retracted with this type of leading edge failure, the airplane could instantly stall. Remember the DC-10 accident where the slats had an uncommanded retraction just after liftoff?

The point remains, why is it a good idea to retract Flaps from a relatively safe configuration to one where the aerodynamic consequences are unknown? The airplane is telling you something is amiss and you need to address it. You're better off planning to get the airplane safely on the ground ASAP rather than climbing to FL320.

Please present a good argument where retracting Flaps at low altitude with an active stick shaker is a proper course of action.
Airplane design is easy, the difficulty is getting them to fly - Barnes Wallis
 
OldAeroGuy
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 7:55 pm

kalvado wrote:
@OldAeroGuy has a reasonably solid argument that flaps shouldn't be raised in that situation, and doing so means crew was planning on further unreasonable things like completing the flight as scheduled..
I find this argument to be at least 50/50 convincing, though last statement is strongly spiced by "Boeing makes great planes, too bad monkeys cannot fly those planes!" agenda.


Please don't these words in my mouth. I never said this or even implied what you are saying.

I resent this statement very much!!
Airplane design is easy, the difficulty is getting them to fly - Barnes Wallis
 
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PixelFlight
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 8:03 pm

rheinwaldner wrote:
Would you keep flying with flaps if the PFD would look like this?

I do not say, that it was not wrong according to Boeings procedures to raise the flaps. It was wrong.

I do say, that the decision to raise the flaps is not wrong IMO if the PFD looks like shown above (or with speed even much deeper in the red area, as they actually had). Would they not have risked to tear the flaps apart if they would not have raised them at the speeds they had?

:checkmark:
That's a good contribution to understand how the decision could have been made.
I hope that the debate will continue with this quality.
 
rheinwaldner
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 8:05 pm

OldAeroGuy wrote:
Please present a good argument where retracting Flaps at low altitude with an active stick shaker is a proper course of action.

This is an argument. Probably even a good one:
Image

Raising the flaps makes the red bars go away...
Many things are difficult, all things are possible!
 
Nils75cz
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 8:06 pm

How much of a bad handling aircraft can be blamed on the pilots? It is not about whether the flights were recoverable. It is about how hard they were to recover and how acceptable it was to let passengers fly in in them. https://m.youtube.com/watch?v=QytfYyHmxtc
With all due respect for the victims, I admit the episode is exaggerating emotions. I still find it shocking. And it contains quite condemning comments from respectable aviation experts. We all laugh at bad pruducts, cheap dowels, tools, bad Chinese tablets and other electronics, shitty garden hoses or toys. But they don't kill people. If you use them carefully, they work. Boeing shouldn't belong in this product category. But their CEO, Mr Muilenburg seems to think so. And that seems to be the problem with thread, with media and with AV-Geek experts. Where is the line to be drawn? I am not an aviation expert. But Boeing screwed up, and even if unintended, the denial is what beats me.
 
kalvado
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 8:10 pm

OldAeroGuy wrote:
kalvado wrote:
@OldAeroGuy has a reasonably solid argument that flaps shouldn't be raised in that situation, and doing so means crew was planning on further unreasonable things like completing the flight as scheduled..
I find this argument to be at least 50/50 convincing, though last statement is strongly spiced by "Boeing makes great planes, too bad monkeys cannot fly those planes!" agenda.


Please don't these words in my mouth. I never said this or even implied what you are saying.

I resent this statement very much!!

My apologies - to some extent. I did not imply that you said anything like that.
However, this is basically the message with "third world pilots" tune playing in all these threads. And this tune is what, from my perspective, strongly affect your opinion "they were crazy idiots, they were going to continue".
Whether you like it or not, though, "monkeys" is the message being widely broadcast - starting from the "read the f&cking manual" AD issued after first JT crash. I just removed politically correct wrappers from that message - and this is what I found behind.
 
OldAeroGuy
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 8:13 pm

rheinwaldner wrote:
OldAeroGuy wrote:
rheinwaldner wrote:
This is wrong. The crews of both crashed MAXes wanted to return.
E.g. here is just one source.
Why do you push wrong information?


All three MAX crews elected to retract Flaps with an active stick shaker.

Stop right here, please. You talked about continuing the mission. And me too. Not about raising flaps. They did not elect to continue the mission. You go beyond published known facts if you claim otherwise.

We can discuss about flaps separately if you like.

I think, they raised the flaps because after about a minute the PFD looked similar like this or even worse (with speed even deeper in the red area):
Image

Would you keep flying with flaps if the PFD would look like this?

I do not say, that it was not wrong according to Boeings procedures to raise the flaps. It was wrong.

I do say, that the decision to raise the flaps is not wrong IMO if the PFD looks like shown above (or with speed even much deeper in the red area, as they actually had). Would they not have risked to tear the flaps apart if they would not have raised them at the speeds they had?


Your PFD display is not accurate. At the point where the crew elected to raise the Flaps, they were below the 250 KIAS Flaps 5 placard. They had three other options:

1) Pulling back the throttle would have been a great option. There was no need to be at takeoff thrust.

2) Increasing pitch angle to control speed would have also have been an option.

3) The "Unreliable Airspeed" NNC would have combined both. Set engine N1 at 80% and 10 deg pitch attitude.

Requesting FL320 and then retracting Flaps doesn't sound like a plan to return. It sounds more like a desire to fly to the destination.
Airplane design is easy, the difficulty is getting them to fly - Barnes Wallis
 
OldAeroGuy
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 8:20 pm

kalvado wrote:
OldAeroGuy wrote:
kalvado wrote:
@OldAeroGuy has a reasonably solid argument that flaps shouldn't be raised in that situation, and doing so means crew was planning on further unreasonable things like completing the flight as scheduled..
I find this argument to be at least 50/50 convincing, though last statement is strongly spiced by "Boeing makes great planes, too bad monkeys cannot fly those planes!" agenda.


Please don't these words in my mouth. I never said this or even implied what you are saying.

I resent this statement very much!!

My apologies - to some extent. I did not imply that you said anything like that.
However, this is basically the message with "third world pilots" tune playing in all these threads. And this tune is what, from my perspective, strongly affect your opinion "they were crazy idiots, they were going to continue".
Whether you like it or not, though, "monkeys" is the message being widely broadcast - starting from the "read the f&cking manual" AD issued after first JT crash. I just removed politically correct wrappers from that message - and this is what I found behind.


Your later statement is no better.

I would have an identical line of reasoning to matter where the crews were from. Now instead of putting words in my mouth, you're putting thoughts in my head.

Don't presume to know what I was thinking. Crew errors are crew errors no matter what airline they fly for.
Airplane design is easy, the difficulty is getting them to fly - Barnes Wallis
 
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PixelFlight
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 8:26 pm

7BOEING7 wrote:
PixelFlight wrote:
Wow! I didn't realize before how incredibly old are the mechanical flaps command design on the 737-8 MAX. Electric flaps command was developed almost 4 decades ago on the A310. For the 737-8 MAX, it look a bit like the pilots have to learn more than the engineers to compensate the very old design.


The point is it's a proven design, lots of spares and there is nothing to learn if you've been flying older model 737's, for both the pilots and the mechanics. And realistically from a pilot's standpoint how much do you need to learn about how to move a flap handle?

The rules to move the flaps look not so trivial in some situations, after having read so many posts about whenever the pilots was allowed to move the flaps or not.
As for the reliability of that very old mechanical design, I was not impressed by what I can see from a search with the word "flaps" on the Aviation Herald.
 
kalvado
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 8:28 pm

OldAeroGuy wrote:
kalvado wrote:
OldAeroGuy wrote:

Please don't these words in my mouth. I never said this or even implied what you are saying.

I resent this statement very much!!

My apologies - to some extent. I did not imply that you said anything like that.
However, this is basically the message with "third world pilots" tune playing in all these threads. And this tune is what, from my perspective, strongly affect your opinion "they were crazy idiots, they were going to continue".
Whether you like it or not, though, "monkeys" is the message being widely broadcast - starting from the "read the f&cking manual" AD issued after first JT crash. I just removed politically correct wrappers from that message - and this is what I found behind.


Your later statement is no better.

I would have an identical line of reasoning to matter where the crews were from. Now instead of putting words in my mouth, you're putting thoughts in my head.

Don't presume to know what I was thinking. Crew errors are crew errors no matter what airline they fly for.

I know you consider flaps up as a error. Which is a quite justifiable position, although there is IMHO still room for discussion and benefit of doubt. We talked about it, lets not start over, we know each other's arguments and there is not much to add without extra data.
But your next conclusion - "that means they wanted to continue" - is IMHO not as logical as you want to believe. And I don't think you would come to that conclusion if US or EU crew did that.
 
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 8:29 pm

rheinwaldner wrote:
OldAeroGuy wrote:
Please present a good argument where retracting Flaps at low altitude with an active stick shaker is a proper course of action.

This is an argument. Probably even a good one:
Image

Raising the flaps makes the red bars go away...


Unfortunately, it is a very bad argument.

If the stick shaker had been going off due to actual leading edge damage, the flight might have been terminated at that point due to a badly disabled wing leading edge.

Badly positioned slats could have caused an uncontrollable wing stall.

Once again, there is a reason procedures are written as they are.
Airplane design is easy, the difficulty is getting them to fly - Barnes Wallis
 
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 8:39 pm

kalvado wrote:
But your next conclusion - "that means they wanted to continue" - is IMHO not as logical as you want to believe. And I don't think you would come to that conclusion if US or EU crew did that.


If a US or EU crew had made the same decision, I would feel the same way.

Despite the stick shaker, the crew language and actions match those of a SID (Standard Instrument Departure).

Knowing that, what do you think their intentions were?
Airplane design is easy, the difficulty is getting them to fly - Barnes Wallis
 
rheinwaldner
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 8:45 pm

OldAeroGuy wrote:
Your PFD display is not accurate. At the point where the crew elected to raise the Flaps, they were below the 250 KIAS Flaps 5 placard.

Ok, correct. They were below 250 but not that much and the speed trend vector showed that approached 250 quickly. Within 10s (and that is the deflection of the trend vector) the 250 would have been reached. So we can say, that they seemed to have raised the flaps in timely manner in order to avoid flaps overspeed.
Note: until now we only discussed why they could have raised the flaps, not anything else. There is a clear logic in raising the flaps, if you cross the flap placard speed otherwise.
Many things are difficult, all things are possible!
 
kalvado
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 8:47 pm

OldAeroGuy wrote:
kalvado wrote:
But your next conclusion - "that means they wanted to continue" - is IMHO not as logical as you want to believe. And I don't think you would come to that conclusion if US or EU crew did that.


If a US or EU crew had made the same decision, I would feel the same way.

Despite the stick shaker, the crew language and actions match those of a SID (Standard Instrument Departure).

Knowing that, what do you think their intentions were?

Well, we talked about it. I would assume they wanted to fly the takeoff profile as they always did and stabilize well above terrain for troubleshooting. Would not work if there is a mechanical problem with the wing. Would work OK if there would be gauge problem and no MCAS.
-Yes, but they also requested climb to FL320!
-As they were in deep shit at that point, climbing as their main defense against crazy trim and they wanted clear airspace above them, for example. Doesn't prove "to destination" intention.
 
slcdeltarumd11
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 8:53 pm

Boeing said that in 2017, several months after deliveries began, engineers became aware that the 737 MAX display system software didn’t meet the original requirements.

I am starting to think we might not see MAX planes in the sky in 2019. Things keep just getting worse for Boeing. Getting FAA approval is only half the challenge at this point. The public isn't going to want to be on them.
 
XRAYretired
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 9:16 pm

PW100 wrote:
Absynth wrote:
https://www.nytimes.com/2019/05/05/business/boeing-737-max-warning-light.html

After discovering the lapse in 2017, Boeing performed an internal review and determined that the lack of a working warning light “did not adversely impact airplane safety or operation,” it said in its statement.


Only after the crash of Lion Air Flight 610 last October did Boeing discuss the matter with the F.A.A. The company then conducted another review and again found the missing alert did not pose a safety threat, and told the F.A.A. as much.


let me get this straight...the Lion Air plane crashes because of a malfunctioning AoA sensor, and they still do not deem it necessary to correct their mistake of having the disagree light disabled? An alert for a sensor failure that caused the crash that should be working? Not only that, but they don't inform the airliners about a critical feature missing, that just caused a crash killing 189 people?

I found the Seattle Times article today already shocking to read. But this is just surreal.


It seems quite unlikley that this "warning light" would have prevented these accidents, as there was no training or anything else linking such light to MCAS. Heck, before the Lionair accident, MCAS was unknown to the complete 737 pilot community. After that, the significance of AoA disagree (or failure) to MCAS was still pretty much unknown, and also it was not universally known to MAX pilots that MCAS was fed of one single AoA sensor.

Boeing may have made a lot of mistakes on the MCAS, but the AoA disagree ommittance is fairly low on the list of significance with respect to both accidents.

I'll have to say it again. If JT043 had AOA Disagree warning (as they would have done if enabled), it is entirely possible it would have been recorded by the pilot (as was IAS and ALT) and addressed by MX prior to JT610. This would have required no knowledge of MCAS.

I may well be a contributing factor to be considered.

Ray
 
OldAeroGuy
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 9:23 pm

kalvado wrote:
-Yes, but they also requested climb to FL320!
-As they were in deep shit at that point, climbing as their main defense against crazy trim and they wanted clear airspace above them, for example. Doesn't prove "to destination" intention.


No, they were not in "deep shit" when they requested FL320. They were still at Flaps 5 with an active stick shaker. MCAS was not active and trim was not a problem.

At 5:39:06, the FO reported to ATC that they were climbing to FL320. The stick shaker was active.

At 5:39:22, autopilot was selected. The left stick shaker was active and Boeing procedure says do not select autopilot with an active stick shaker

At 5:39:42, Level Change was selected to FL320. The left stick shaker was active.

At 5:39:45, the Captain asked the FO to retract Flaps. Boeing procedure says do not retract Flaps with an active stick shaker. The left stick shaker was active.

Please stay with the facts if the discussion is going to be accurate.
Airplane design is easy, the difficulty is getting them to fly - Barnes Wallis
 
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PW100
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 9:27 pm

OldAeroGuy wrote:
There are good reasons the procedures are written the way they are. I've written about this previously. The point is, the crew do not know the state of their airplane. They only know a stick shaker is going off.

They also know the other stick shaker is not going off.

You keep pounding on the stick shaker going off, and tying conclusions to that.

I'm just wondering if a crew is at liberty to determine that when only one of the two stick shakers is going off, if they can/may make interpretations and (eventually) arrive at a conclusion that the single one going off is bogus. If so, then I'd be careful at pinning conclusions to their actions with respect to not following published procedures in that respect.
Immigration officer: "What's the purpose of your visit to the USA?" Spotter: "Shooting airliners with my Canon!"
 
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PW100
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 9:31 pm

XRAYretired wrote:
PW100 wrote:
Absynth wrote:
https://www.nytimes.com/2019/05/05/business/boeing-737-max-warning-light.html





let me get this straight...the Lion Air plane crashes because of a malfunctioning AoA sensor, and they still do not deem it necessary to correct their mistake of having the disagree light disabled? An alert for a sensor failure that caused the crash that should be working? Not only that, but they don't inform the airliners about a critical feature missing, that just caused a crash killing 189 people?

I found the Seattle Times article today already shocking to read. But this is just surreal.


It seems quite unlikley that this "warning light" would have prevented these accidents, as there was no training or anything else linking such light to MCAS. Heck, before the Lionair accident, MCAS was unknown to the complete 737 pilot community. After that, the significance of AoA disagree (or failure) to MCAS was still pretty much unknown, and also it was not universally known to MAX pilots that MCAS was fed of one single AoA sensor.

Boeing may have made a lot of mistakes on the MCAS, but the AoA disagree ommittance is fairly low on the list of significance with respect to both accidents.

I'll have to say it again. If JT043 had AOA Disagree warning (as they would have done if enabled), it is entirely possible it would have been recorded by the pilot (as was IAS and ALT) and addressed by MX prior to JT610. This would have required no knowledge of MCAS.

I may well be a contributing factor to be considered.

Ray


Of course it's a factor to be considered. The ground maintenance and troubleshooting will definately benefit from more data.
But my point is, that it would probably not have provided much help to the JT and ET pilots. It is a factor pretty low on the scale of things.

And for the JT, if the accident crew would have flow the flight(s) before, the maintenance issue would not have seen the day of light to begin with . . .
Immigration officer: "What's the purpose of your visit to the USA?" Spotter: "Shooting airliners with my Canon!"
 
kalvado
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 9:33 pm

OldAeroGuy wrote:
kalvado wrote:
-Yes, but they also requested climb to FL320!
-As they were in deep shit at that point, climbing as their main defense against crazy trim and they wanted clear airspace above them, for example. Doesn't prove "to destination" intention.


No, they were not in "deep shit" when they requested FL320. They were still at Flaps 5 with an active stick shaker. MCAS was not active and trim was not a problem.

At 5:39:06, the FO reported to ATC that they were climbing to FL320. The stick shaker was active.

At 5:39:22, autopilot was selected. The left stick shaker was active and Boeing procedure says do not select autopilot with an active stick shaker

At 5:39:42, Level Change was selected to FL320. The left stick shaker was active.

At 5:39:45, the Captain asked the FO to retract Flaps. Boeing procedure says do not retract Flaps with an active stick shaker. The left stick shaker was active.

Please stay with the facts if the discussion is going to be accurate.

I can come up with some other explanation if you want. That the request was in the mental pipeline and came out automatically, before realizing there was a problem, for example.
Point here is not to argue about aerodynamics or possible fault trees. Point here is that the crew - who cannot stand for their decisions - at least deserves the benefit of doubt, rather than stating the worst possible conclusion as a medical fact. And I re-iterate: I don't believe that bias would occur without "third world pilots" "only 200 hours" background.
 
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7BOEING7
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 9:35 pm

rheinwaldner wrote:

I think, they raised the flaps because after about a minute the PFD looked similar like this or even worse (with speed even deeper in the red area):
Image


Good cut and paste (except for the digital airspeed) -- it would have been even better if you had shown the AOA DISAGREE hardly noticeable in the lower righthand corner (737NG).

But, if you actually had a bad AOA the "red squares" would have probably extended from the bottom to the top of the displayed airspeed tape so the very visible flaps up demarcation would not have been near as visible as it is in your example.
 
airnorth
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 9:36 pm

PW100 wrote:
OldAeroGuy wrote:
There are good reasons the procedures are written the way they are. I've written about this previously. The point is, the crew do not know the state of their airplane. They only know a stick shaker is going off.

They also know the other stick shaker is not going off.

You keep pounding on the stick shaker going off, and tying conclusions to that.

I'm just wondering if a crew is at liberty to determine that when only one of the two stick shakers is going off, if they can/may make interpretations and (eventually) arrive at a conclusion that the single one going off is bogus. If so, then I'd be careful at pinning conclusions to their actions with respect to not following published procedures in that respect.


I could see a choice for the crew if only one stick shaker is active as dangerous. I would think that if either, or both were active that the crew would run the same procedure, just seems to make sense, simple, and safe.
 
Amexair
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 9:46 pm

PW100 wrote:
OldAeroGuy wrote:
rheinwaldner wrote:
This is wrong. The crews of both crashed MAXes wanted to return.
E.g. here is just one source.
Why do you push wrong information?


All three MAX crews elected to retract Flaps with an active stick shaker. This is contrary to the published Boeing procedure.
If the three crews were not focused on completing their planned missions, why would they have retracted the Flaps?
For JT043, after STAB TRIM was deactivated, the planned flight was completed with the left stick shaker active.
For ET302, at 5:39:06, the FO reported to ATC that they were climbing to FL320. The stick shaker was active.
At 5:39:22, autopilot was selected. The left stick shaker was active and Boeing procedure says do not select autopilot with an active stick shaker
At 5:39:42, Level Change was selected to FL320. The left stick shaker was active.
At 5:39:45, the Captain asked the FO to retract Flaps. Boeing procedure says do not retract Flaps with an active stick shaker. The left stick shaker was active.
At 5:39:55, the autopilot disengaged. The left stick shaker was active.
At 5:39:57, the Captain asked the FO to maintain runway heading as they were having control issues as the autopilot was disconnected. The left stick shaker was active.
The above actions indicate that the ET302 was focused on continuing their mission with an active stick shaker.
At 5:40:00, MCAS began to pitch the airplane nose down. The left stick shaker was active.
At 5:42:10, after struggling with trim due to MCAS activity, the crew contacted ATC with a request for a return to land. This is the request your source cited.

https://www.flightradar24.com/blog/wp-c ... -ET302.pdf

While you are correct in saying that ET302 did request a return to land, they only did so after taking actions contrary to Boeing procedure and attempting to climb to a cruise altitude.
With stick shaker after liftoff, the correct actions would have been to leave the Flaps at the Takeoff setting and request a return to land without trying to climb to FL320.


Could the ET crew be forgiven for not following said procedure, when only one stick shaker was going off, when they determined that the stick shaker going off must have been false?

As you wrote earlier, the published procedure does not include such provisions. Some woud argue that this exactly is the reason why we have pilots: to make these sort of decisions and determine that such procedure may not not applicable to the specific situation in hand? Don't you think it would be premature at this stage to hold that against the crew, when we don't understand for sure why they choose not to follow said procedure?


Thanks. The guy is starting to sound like a broken record.
 
OldAeroGuy
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 9:52 pm

airnorth wrote:
PW100 wrote:
OldAeroGuy wrote:
There are good reasons the procedures are written the way they are. I've written about this previously. The point is, the crew do not know the state of their airplane. They only know a stick shaker is going off.

They also know the other stick shaker is not going off.

You keep pounding on the stick shaker going off, and tying conclusions to that.

I'm just wondering if a crew is at liberty to determine that when only one of the two stick shakers is going off, if they can/may make interpretations and (eventually) arrive at a conclusion that the single one going off is bogus. If so, then I'd be careful at pinning conclusions to their actions with respect to not following published procedures in that respect.


I could see a choice for the crew if only one stick shaker is active as dangerous. I would think that if either, or both were active that the crew would run the same procedure, just seems to make sense, simple, and safe.


You're exactly correct. If a stick shaker is active, you don't want the crew doing an analysis.

One or both, the procedure is the same.
Airplane design is easy, the difficulty is getting them to fly - Barnes Wallis
 
kalvado
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 9:58 pm

OldAeroGuy wrote:
airnorth wrote:
PW100 wrote:
They also know the other stick shaker is not going off.

You keep pounding on the stick shaker going off, and tying conclusions to that.

I'm just wondering if a crew is at liberty to determine that when only one of the two stick shakers is going off, if they can/may make interpretations and (eventually) arrive at a conclusion that the single one going off is bogus. If so, then I'd be careful at pinning conclusions to their actions with respect to not following published procedures in that respect.


I could see a choice for the crew if only one stick shaker is active as dangerous. I would think that if either, or both were active that the crew would run the same procedure, just seems to make sense, simple, and safe.


You're exactly correct. If a stick shaker is active, you don't want the crew doing an analysis.

One or both, the procedure is the same.

If you will, deviation from prescribed procedure can be an honest mistake, an evil wrongdoing, or a thoughtful analysis - or anything in between. For some reason, you're adamant on conviction. Which, actually, can have some interesting implications if your style of thinking is followed.
 
OldAeroGuy
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 10:02 pm

kalvado wrote:
OldAeroGuy wrote:

At 5:39:42, Level Change was selected to FL320. The left stick shaker was active.


I can come up with some other explanation if you want. That the request was in the mental pipeline and came out automatically, before realizing there was a problem, for example.
Point here is not to argue about aerodynamics or possible fault trees. Point here is that the crew - who cannot stand for their decisions - at least deserves the benefit of doubt, rather than stating the worst possible conclusion as a medical fact.


The verbal response is one thing, but there was a physical response as well. See the bolded words above. Some one had to select the Level Change to FL320.

kalvado wrote:
[And I re-iterate: I don't believe that bias would occur without "third world pilots" "only 200 hours" background.


I don't understand these constant "bias" comments. Please drop this recurrent innuendo. It's not in my line of argument.
Airplane design is easy, the difficulty is getting them to fly - Barnes Wallis
 
kalvado
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 10:09 pm

OldAeroGuy wrote:

kalvado wrote:
[And I re-iterate: I don't believe that bias would occur without "third world pilots" "only 200 hours" background.


I don't understand these constant "bias" comments. Please drop this recurrent innuendo. It's not in my line of argument.

No problem, once you drop prejudice against the crew - my impression disappears as well. Otherwise we can keep our opinions intact - both are justified to approximately same extent.
 
OldAeroGuy
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 10:16 pm

kalvado wrote:
OldAeroGuy wrote:
airnorth wrote:

I could see a choice for the crew if only one stick shaker is active as dangerous. I would think that if either, or both were active that the crew would run the same procedure, just seems to make sense, simple, and safe.


You're exactly correct. If a stick shaker is active, you don't want the crew doing an analysis.

One or both, the procedure is the same.

If you will, deviation from prescribed procedure can be an honest mistake, an evil wrongdoing, or a thoughtful analysis - or anything in between. For some reason, you're adamant on conviction. Which, actually, can have some interesting implications if your style of thinking is followed.


It comes down to a crew training issue. It is fairly easy to train for normal operation, particularly with today's automation levels. Hence the description "Children of the Magenta Line".

I hope that every crew is capable of "Good Airmanship" and is well schooled on how to apply the NNC's (Non-Normal Checklists) when faced with something other than Day-to-Day operation.

NNC's are created to simplify situations and devolve to safe outcomes. Crews can always deviate from them but then become responsible for the results of the deviation.
Airplane design is easy, the difficulty is getting them to fly - Barnes Wallis
 
OldAeroGuy
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 10:25 pm

kalvado wrote:
OldAeroGuy wrote:

kalvado wrote:
[And I re-iterate: I don't believe that bias would occur without "third world pilots" "only 200 hours" background.


I don't understand these constant "bias" comments. Please drop this recurrent innuendo. It's not in my line of argument.

No problem, once you drop prejudice against the crew - my impression disappears as well. Otherwise we can keep our opinions intact - both are justified to approximately same extent.


I've merely pointed out the facts of the crew actions that have been published to date versus the Boeing published procedures.

It's strange that you judge that as "prejudice". Since you have decided that I'm "prejudiced", please provide some examples.

Please note the definition: Prejudice - "preconceived opinion that is not based on reason or actual experience"
Airplane design is easy, the difficulty is getting them to fly - Barnes Wallis
 
OldAeroGuy
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Mon May 06, 2019 10:32 pm

PW100 wrote:
OldAeroGuy wrote:
There are good reasons the procedures are written the way they are. I've written about this previously. The point is, the crew do not know the state of their airplane. They only know a stick shaker is going off.

They also know the other stick shaker is not going off.

You keep pounding on the stick shaker going off, and tying conclusions to that.

I'm just wondering if a crew is at liberty to determine that when only one of the two stick shakers is going off, if they can/may make interpretations and (eventually) arrive at a conclusion that the single one going off is bogus. If so, then I'd be careful at pinning conclusions to their actions with respect to not following published procedures in that respect.


I do know that two pilots, Zeke and 7BOEING7, have been active on this thread.

Both have agreed with what I've "pounded on" about stick shaker after liftoff actions/procedures.
Airplane design is easy, the difficulty is getting them to fly - Barnes Wallis

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