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MaksFly
Posts: 367
Joined: Fri Jun 24, 2016 5:50 am

Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 2:09 am

SuseJ772 wrote:
F9Animal wrote:
I find it rather disturbing that technology to prevent an accident, hinders a crew ability to save a plane when that technology fails. Can you imagine what those pilots faced in the final moments? At such a low altitude, troubleshooting is not much of an option, especially when they couldn't maintain level flight.

As my uncle once said.... We have become too reliant on technology, and stick and rudder days are pretty much gone. A "WTF" situation on takeoff has to be pretty horrifying.
This is statistically wrong. We are at the safest time in aviation history by far. While at the same time the highest amount of automation. Yes automation can be over relied on. But is has also saved untold thousands of lives. Which we will never know that number so a comparison is useless with the data we have.


the question is however... how much of this is due to automation versus better engineering and manufacturing of aircraft.

Watching crash investigation videos it seems like older incidents were largely manufacturing defects and uncovered faults, often saved by superior piloting, versus the more recent accidents are pilot error induced by over reliance on automation and the disconnect from pilots effectively being pilots.

Yes, I am sure automation has in many cases saved lives... but when automation fails, are we supposed to hit "control + Alt + Delete" and say "shit happens?"

Take a look at all of the Tesla crashes on auto pilot... MOST if not ALL accidents which would not happen had the driver actually been a driver instead of a passenger.

I feel automation is supposed to help the pilots... but it should not cross the line and make things more difficult for them to figure out the basics.
 
Trin
Posts: 167
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 2:25 am

VS11 wrote:
"Southwest, American pilots unions question 737 Max documentation after Indonesia crash"

"Two U.S. pilots' unions say the potential risks of a safety feature on Boeing Co.'s 737 Max aircraft that has been linked to a deadly crash in Indonesia weren't sufficiently spelled out in their manuals or training.

Boeing and the Federal Aviation Administration issued directives last week telling flight crews about the system, which is designed to provide extra protection against pilots losing control. That prompted aviators, unions and training departments to realize that none of the documentation for the Max aircraft included an explanation of the system, the union leaders said."

https://www.dallasnews.com/business/air ... esia-crash


I find that very disconcerting. The merest hint that newer versions of aircraft can slip into general use without extensive descriptions of any differences to pilots is really mind boggling. Not only that, but the fact that nobody in the design and testing phase of the MAX ever once considered how the automatic trim system would perform in the event that the aircraft's systems are suffering from polluted air/speed/AoA data from faulty/blocked/frozen sensors is just really unbelievable to me. It's not as if sensor trouble/faulty air data is such an outlandish eventuality......EVERY vital flying component and automatic process that the aircraft implements in an attempt to maintain stable flight configurations should be put through its paces WHILE operating on toxic data. EVERY one of them.

Trin
 
LDRA
Posts: 328
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 3:39 am

VS11 wrote:
"Southwest, American pilots unions question 737 Max documentation after Indonesia crash"

"Two U.S. pilots' unions say the potential risks of a safety feature on Boeing Co.'s 737 Max aircraft that has been linked to a deadly crash in Indonesia weren't sufficiently spelled out in their manuals or training.

Boeing and the Federal Aviation Administration issued directives last week telling flight crews about the system, which is designed to provide extra protection against pilots losing control. That prompted aviators, unions and training departments to realize that none of the documentation for the Max aircraft included an explanation of the system, the union leaders said."

https://www.dallasnews.com/business/air ... esia-crash


Damning...

Is this MCAS added in order to maintain same flight characteristics as older 737NG?
 
F9Animal
Posts: 4435
Joined: Thu Dec 16, 2004 7:13 am

Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 3:45 am

MaksFly wrote:
SuseJ772 wrote:
F9Animal wrote:
I find it rather disturbing that technology to prevent an accident, hinders a crew ability to save a plane when that technology fails. Can you imagine what those pilots faced in the final moments? At such a low altitude, troubleshooting is not much of an option, especially when they couldn't maintain level flight.

As my uncle once said.... We have become too reliant on technology, and stick and rudder days are pretty much gone. A "WTF" situation on takeoff has to be pretty horrifying.
This is statistically wrong. We are at the safest time in aviation history by far. While at the same time the highest amount of automation. Yes automation can be over relied on. But is has also saved untold thousands of lives. Which we will never know that number so a comparison is useless with the data we have.


the question is however... how much of this is due to automation versus better engineering and manufacturing of aircraft.

Watching crash investigation videos it seems like older incidents were largely manufacturing defects and uncovered faults, often saved by superior piloting, versus the more recent accidents are pilot error induced by over reliance on automation and the disconnect from pilots effectively being pilots.

Yes, I am sure automation has in many cases saved lives... but when automation fails, are we supposed to hit "control + Alt + Delete" and say "shit happens?"

Take a look at all of the Tesla crashes on auto pilot... MOST if not ALL accidents which would not happen had the driver actually been a driver instead of a passenger.

I feel automation is supposed to help the pilots... but it should not cross the line and make things more difficult for them to figure out the basics.


I do agree. There has to be a way to quickly determine if the automation might be faulty, and at low altitude, troubleshooting isnt really something that can be done. I'm not so much speaking for this crash, I am speaking about how reliant we have all become on technology. I just couldn't imagine what that cockpit was like in the final seconds.

As someone mentioned, technology has saved lives. But, it drives me nuts when technology can give us endings like this. Flying will always become safer, but its just sad that it takes so much trial and error to perfect this.

So, if it is the AOA Sensor, will the crew also be blamed for this? Could have, should have, would have?
I Am A Different Animal!!
 
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7BOEING7
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 3:59 am

VS11 wrote:
"Southwest, American pilots unions question 737 Max documentation after Indonesia crash"

"Two U.S. pilots' unions say the potential risks of a safety feature on Boeing Co.'s 737 Max aircraft that has been linked to a deadly crash in Indonesia weren't sufficiently spelled out in their manuals or training.

Boeing and the Federal Aviation Administration issued directives last week telling flight crews about the system, which is designed to provide extra protection against pilots losing control. That prompted aviators, unions and training departments to realize that none of the documentation for the Max aircraft included an explanation of the system, the union leaders said."

https://www.dallasnews.com/business/air ... esia-crash


Non event — airline pilots have been complaining for years that there isn’t enough information/description in the FCOM — they want the “good old days”.
 
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QuarkFly
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 4:35 am

mandala499 wrote:
Something we need to have a look at here:
https://leehamnews.com/2018/11/07/boein ... -accident/

Any such Automatic trim action which doesn’t makes sense has the feel of a runaway pitch trim which is a very common emergency simulator training scenario. In isolation, this should be easy to spot and the correct action (Cut out the trim as described below) could be taken in relative calmness. I’m inclined to think the JT610 crew had to handle a more difficult and stressing false Stall warning and recovery situation, which is the same between the 737NG and the 737 MAX.

The Stall warning and recovery functions are:

Above a preset AOA, a stall warning audio voice says: “Stall, Stall, Stall” and the Pilots control yoke on the side with the high AOA start shaking as an additional physical warning
If the AOA does not decrease after the triggered Stick Shaker but stays at a high angle, the system then creates a stronger control Yoke force through the Elevator Feel & Centering unit by applying a nose down stick force for the present Yoke position.
As an additional measure, the Flight Control Computer starts a stabilizer trim nose down movement using the Autopilot trim channel. The trim action lasts 10 seconds. The Pilot’s can counteract the trim by using their trim buttons, it overrides the Stall system trim.
If the AOA persists, the Pitch trim nose down will trigger again after a certain time lapse. If the PIlots have counter trimmed, the system waits 5 seconds until it repeats the trim nose down for 10 seconds


I tend to agree that they've got their hands full... If false AOA reading can trigger the STS nose down trim, wouldn't it also trigger the stick shaker, and the stick pusher function too? And to do that in unreliable airspeed (pitch n power)?

That said - was the AOA replaced correctly?

I wonder if the replaced AOA vane was broken at all... if it turns out that it was not broken, this accident investigation will become very very interesting...


I totally agree about the so-called pesky broken AOA sensor...everybody is just assuming that a bad AOA vane is at least part of the issue...it may never have been broken -- thus replacing it had no effect. Waiting for evidence -- is the best policy!

However, I always wondered what B was going to do about those big heavy LEAP engines cantilevered farther out in front of the MAX wing, pushing the CG even farther forward...without AFAIK, a bigger horizontal stabilizer to balance things out. Probably even a worse issue on the 737-7Max. Now we know what B did -- they sneak in band-aids like MCAS while zipping their lips about it.

I will say that B has really been successful keeping the 737 a big seller through new engine offerings and upgrades. But STS and MCAS just shows that the old non-FBW flight control system probably can't keep up with the engine and airframe mods anymore. If I were a carrier buying narrow-bodies, unless I had a big fleet of existing 737's and associated trained pilots -- I would hesitate, maybe unfairly, to add the MAX to my fleet knowing it may be flying past the 2040 time frame -- with its over matched non-FBW flight controls.

Too bad NSA never came before NMA.
Always take the Red Eye if possible
 
Myriad
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 5:03 am

7BOEING7 wrote:

Non event — airline pilots have been complaining for years that there isn’t enough information/description in the FCOM — they want the “good old days”.


From the WSJ
https://www.wsj.com/articles/boeing-wit ... _lead_pos2
"Boeing Co. BA -3.33% withheld information about potential hazards associated with a new flight-control feature suspected of playing a role in last month’s fatal Lion Air jet crash, according to safety experts involved in the investigation, as well as midlevel FAA officials and airline pilots."
"Boeing is working on a software fix, according to industry and government officials, that would likely mitigate risks. On Saturday, the company went further than before in spelling out dangers pilots can face if they misinterpret or respond too slowly to counter automated commands. In a message sent to all 737 operators, and reviewed by The Wall Street Journal, the Chicago plane maker explained in painstaking detail the engineering principles and operational parameters behind the latest automation.
Boeing’s latest communications with airlines prompted American’s union to alert its members. “This is the first description you, as 737 pilots, have seen,” the union pointedly told pilots in a memo, referring to the 737 MAX stall-prevention system. Noting the system wasn’t mentioned in American Airlines’ or Boeing manuals, the union memo added: “It will be soon.”
 
LupineChemist
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 5:17 am

Trin wrote:
VS11 wrote:
"Southwest, American pilots unions question 737 Max documentation after Indonesia crash"

"Two U.S. pilots' unions say the potential risks of a safety feature on Boeing Co.'s 737 Max aircraft that has been linked to a deadly crash in Indonesia weren't sufficiently spelled out in their manuals or training.

Boeing and the Federal Aviation Administration issued directives last week telling flight crews about the system, which is designed to provide extra protection against pilots losing control. That prompted aviators, unions and training departments to realize that none of the documentation for the Max aircraft included an explanation of the system, the union leaders said."

https://www.dallasnews.com/business/air ... esia-crash


I find that very disconcerting. The merest hint that newer versions of aircraft can slip into general use without extensive descriptions of any differences to pilots is really mind boggling. Not only that, but the fact that nobody in the design and testing phase of the MAX ever once considered how the automatic trim system would perform in the event that the aircraft's systems are suffering from polluted air/speed/AoA data from faulty/blocked/frozen sensors is just really unbelievable to me. It's not as if sensor trouble/faulty air data is such an outlandish eventuality......EVERY vital flying component and automatic process that the aircraft implements in an attempt to maintain stable flight configurations should be put through its paces WHILE operating on toxic data. EVERY one of them.

Trin


Honestly, it seems even worse than that. That they added a system but took the commercial decision to not train pilots on it in order to better sell the commonality. In short, Boeing marketing overruling technical expertise directly led to these poor people's death. If this is true, this should be a major scandal.
 
benjjk
Posts: 388
Joined: Fri Aug 08, 2014 4:29 am

Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 5:32 am

LDRA wrote:
VS11 wrote:
"Southwest, American pilots unions question 737 Max documentation after Indonesia crash"

"Two U.S. pilots' unions say the potential risks of a safety feature on Boeing Co.'s 737 Max aircraft that has been linked to a deadly crash in Indonesia weren't sufficiently spelled out in their manuals or training.

Boeing and the Federal Aviation Administration issued directives last week telling flight crews about the system, which is designed to provide extra protection against pilots losing control. That prompted aviators, unions and training departments to realize that none of the documentation for the Max aircraft included an explanation of the system, the union leaders said."

https://www.dallasnews.com/business/air ... esia-crash


Damning...

Is this MCAS added in order to maintain same flight characteristics as older 737NG?


As I understand it, the MCAS was added to assist with stall prevention/recovery, because the Max is harder to recover due to the forward CG. It only operates in manual, flaps-up flight at high angle of attack. A certification requirement would have been for the Max to have virtually identical flight characteristics to the NGs which in normal flight it does (I assume), but not at high AoA. Happy to be corrected on any of this by someone with some actual 737 experience.

Probably not a great move to not even mention the system once in the training packs, given how it is a shift away from the perceived Boeing philosophy of the pilot having the final say in what happens. Whether pilot awareness of it would have saved this flight we can't say though. I can't see how the MCAS by itself could bring down the aircraft if it can be so easily corrected by pulling back on the yoke and applying some trim, or the usual trim runaway procedure. Something else was going badly wrong in that cockpit.
 
maint123
Posts: 396
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 5:46 am

VS11 wrote:
"Southwest, American pilots unions question 737 Max documentation after Indonesia crash"

"Two U.S. pilots' unions say the potential risks of a safety feature on Boeing Co.'s 737 Max aircraft that has been linked to a deadly crash in Indonesia weren't sufficiently spelled out in their manuals or training.

Boeing and the Federal Aviation Administration issued directives last week telling flight crews about the system, which is designed to provide extra protection against pilots losing control. That prompted aviators, unions and training departments to realize that none of the documentation for the Max aircraft included an explanation of the system, the union leaders said."

https://www.dallasnews.com/business/air ... esia-crash


Exactly what I have been stressing but a lot of circling of the wagons on this site.
All Max planes should be grounded until thorough inspection of the Max series is completed.
Their should be a investigation of both Boeing as well as the US certifying body, they seem too closely entwined.
 
PlanesNTrains
Posts: 9524
Joined: Tue Feb 01, 2005 4:19 pm

Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 6:07 am

maint123 wrote:
VS11 wrote:
"Southwest, American pilots unions question 737 Max documentation after Indonesia crash"

"Two U.S. pilots' unions say the potential risks of a safety feature on Boeing Co.'s 737 Max aircraft that has been linked to a deadly crash in Indonesia weren't sufficiently spelled out in their manuals or training.

Boeing and the Federal Aviation Administration issued directives last week telling flight crews about the system, which is designed to provide extra protection against pilots losing control. That prompted aviators, unions and training departments to realize that none of the documentation for the Max aircraft included an explanation of the system, the union leaders said."

https://www.dallasnews.com/business/air ... esia-crash


Exactly what I have been stressing but a lot of circling of the wagons on this site.
All Max planes should be grounded until thorough inspection of the Max series is completed.
Their should be a investigation of both Boeing as well as the US certifying body, they seem too closely entwined.


Just curious what the grounding is for? What would they be looking for? Usually groundings seem to be done when there is an imminent threat or known defect that is of such a level of danger that continuing to fly the aircraft would be out of the question. In this case, regardless of whether Boeing handled it appropriately or not, there appears to be a fairly simple fix via better training materials and communication. Unless there is something that can be pointed to that would make flying the aircraft unacceptable, I don't see what a grounding would accomplish?
-Dave


MAX’d out on MAX threads. If you are starting a thread, and it’s about the MAX - stop. There’s already a thread that covers it.
 
maint123
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 6:26 am

PlanesNTrains wrote:
maint123 wrote:
VS11 wrote:
"Southwest, American pilots unions question 737 Max documentation after Indonesia crash"

"Two U.S. pilots' unions say the potential risks of a safety feature on Boeing Co.'s 737 Max aircraft that has been linked to a deadly crash in Indonesia weren't sufficiently spelled out in their manuals or training.

Boeing and the Federal Aviation Administration issued directives last week telling flight crews about the system, which is designed to provide extra protection against pilots losing control. That prompted aviators, unions and training departments to realize that none of the documentation for the Max aircraft included an explanation of the system, the union leaders said."

https://www.dallasnews.com/business/air ... esia-crash


Exactly what I have been stressing but a lot of circling of the wagons on this site.
All Max planes should be grounded until thorough inspection of the Max series is completed.
Their should be a investigation of both Boeing as well as the US certifying body, they seem too closely entwined.


Just curious what the grounding is for? What would they be looking for? Usually groundings seem to be done when there is an imminent threat or known defect that is of such a level of danger that continuing to fly the aircraft would be out of the question. In this case, regardless of whether Boeing handled it appropriately or not, there appears to be a fairly simple fix via better training materials and communication. Unless there is something that can be pointed to that would make flying the aircraft unacceptable, I don't see what a grounding would accomplish?

Read what the AMERICAN pilots are saying.
1. Inadequate and negligible training.
2. No new documentation.

Also 190 odd deaths in a new unproven Boeing plane due to above .
If it was some other country, maybe a car crash , even with a couple of deaths , by now a congressional committee would be on the job, with 1000s of cars recalled.
That's why I said Boeing did a lousy job but the certifying personnel also have to be questioned.
 
ferpe
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 6:59 am

7BOEING7 wrote:
maint123 wrote:
Or why have a manual mode only in MAX, where the pilots will still be overridden by automation ?


The only time the pilot can be overridden with this system is if he has his hands off the controls or is pushing the nose over (then he's getting help) -- if he has his hands on the controls and has some back force (which he would if the airplane was trying to nose over) the automatic nose down trim is overridden.


In none of the communication from Boeing, including in the description of MCAS to the airlines, is this feature of the normal trim behavior included. And for good reason. The intent of MCAS, to increase the stability of the MAX 8 and 9 in hard turns or other maneuvers which bring AOA over a threshold close to stall, would be nulled by such a logic. Per definition, PF is pulling back on the Yoke hard in the design case and MCAS shall then trim nose down. The function would be inhibited by leaving the Yoke switches in the loop, they cannot be. MCAS is rather an extension of the Stall recovery trim action down in AOA, to a region below stick shaker and EFS/Stall trim action. It's best viewed as a non-annunciated extension of the stall protection system.

When PF is pulling hard on the Yoke to stop a nose down pitch and the high AOA persists, the MCAS will continue to trim nose down. It will only be stopped intermittently by manual trim or permanently by CUTOUT switches.
Non French in France
 
rocketPower
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 8:21 am

This whole situation amplifies the too comfortable relationship between the FAA and Boeing.

This is not just my opinion but that of many on the inside of the industry.
rocketPower

Life is about enjoying being uncomfortable. If you're complacent, something is wrong!
 
WIederling
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 8:26 am

MaksFly wrote:
Watching crash investigation videos it seems like older incidents were largely manufacturing defects and uncovered faults, often saved by superior piloting,

Crash "Investigation" productions are fiction with a sprinkling of some unimportant elements taken from reality.
( think James Bond books vs the movies :-)

MaksFly wrote:
versus the more recent accidents are pilot error induced by over reliance on automation and the disconnect from pilots effectively being pilots.

Yes, I am sure automation has in many cases saved lives... but when automation fails, are we supposed to hit "control + Alt + Delete" and say "shit happens?"

Take a look at all of the Tesla crashes on auto pilot... MOST if not ALL accidents which would not happen had the driver actually been a driver instead of a passenger.

I feel automation is supposed to help the pilots... but it should not cross the line and make things more difficult for them to figure out the basics.


Obviously automation will make different errors ( by design, by chance ) than humans.

Overall incident/accident rate has continuously gone down over time.

All the regular issues that crop up have been strongly alleviated by way
of CRM, training and technology ( be that more reliable tech or automation )

What you see today are complete outliers that stand alone. Zero or just a few repeat cases far apart.
_And_ those are now the bottom scrapings of a box to the brim full of hurt in the past.

IMU your lament is plain wrong and does not scope in reality.
Murphy is an optimist
 
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Starlionblue
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 8:33 am

MaksFly wrote:
SuseJ772 wrote:
F9Animal wrote:
I find it rather disturbing that technology to prevent an accident, hinders a crew ability to save a plane when that technology fails. Can you imagine what those pilots faced in the final moments? At such a low altitude, troubleshooting is not much of an option, especially when they couldn't maintain level flight.

As my uncle once said.... We have become too reliant on technology, and stick and rudder days are pretty much gone. A "WTF" situation on takeoff has to be pretty horrifying.
This is statistically wrong. We are at the safest time in aviation history by far. While at the same time the highest amount of automation. Yes automation can be over relied on. But is has also saved untold thousands of lives. Which we will never know that number so a comparison is useless with the data we have.


the question is however... how much of this is due to automation versus better engineering and manufacturing of aircraft.

Watching crash investigation videos it seems like older incidents were largely manufacturing defects and uncovered faults, often saved by superior piloting, versus the more recent accidents are pilot error induced by over reliance on automation and the disconnect from pilots effectively being pilots.

Yes, I am sure automation has in many cases saved lives... but when automation fails, are we supposed to hit "control + Alt + Delete" and say "shit happens?"

Take a look at all of the Tesla crashes on auto pilot... MOST if not ALL accidents which would not happen had the driver actually been a driver instead of a passenger.

I feel automation is supposed to help the pilots... but it should not cross the line and make things more difficult for them to figure out the basics.


I don't think you can compare with Tesla "autopilot crashes". Airline pilots are almost universally well trained, and on the specific type. Additionally, we go through regular checks and recurrent training. Anyone with a driver's license, not a very hard thing to get, can buy a Tesla and drive it without any training on the features of the car. That driver's license might have been issued decades previously, with no additional training since then.

Pilots in general know very well how to act when automation "lets them down". In fact, much of our training is about understanding the automation. It includes plenty of "failed automation" and "degraded automation" knowledge and scenarios.

A very basic Airbus rule on use automation goes more or less as follows:
- If a managed mode (fully automated) does not give you the expected result, use a selected mode (autoflight but manually selected parameters).
- If a selected mode does not give you the expected result either, disengage the automation and fly manually.
In other words, don't try to fiddle with the programming "on the fly". Use a lesser degree of automation, or none at all, to get the result you want. Then once the aircraft is doing what you want, re-program and re-engage as appropriate.

The automation is designed to help us, not make us helpless.
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
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Finn350
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 8:52 am

Myriad wrote:
7BOEING7 wrote:

Non event — airline pilots have been complaining for years that there isn’t enough information/description in the FCOM — they want the “good old days”.


From the WSJ
https://www.wsj.com/articles/boeing-wit ... _lead_pos2
"Boeing Co. BA -3.33% withheld information about potential hazards associated with a new flight-control feature suspected of playing a role in last month’s fatal Lion Air jet crash, according to safety experts involved in the investigation, as well as midlevel FAA officials and airline pilots."
"Boeing is working on a software fix, according to industry and government officials, that would likely mitigate risks. On Saturday, the company went further than before in spelling out dangers pilots can face if they misinterpret or respond too slowly to counter automated commands. In a message sent to all 737 operators, and reviewed by The Wall Street Journal, the Chicago plane maker explained in painstaking detail the engineering principles and operational parameters behind the latest automation.
Boeing’s latest communications with airlines prompted American’s union to alert its members. “This is the first description you, as 737 pilots, have seen,” the union pointedly told pilots in a memo, referring to the 737 MAX stall-prevention system. Noting the system wasn’t mentioned in American Airlines’ or Boeing manuals, the union memo added: “It will be soon.”


I am sure that Boeing can correct the design flaw in 737MAX but I am surprised that Boeing was not forthcoming in the initial communication regarding the accident. They tried to emphasize that pilot training & manuals are adequate and not admit that there is a design issue.

As some have stated earlier, 737 as a whole is a legacy design and implementing FBW and envelope protection features in 737MAX is prone to flaws.
 
SteinarN
Posts: 178
Joined: Mon Dec 29, 2014 1:26 pm

Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 9:02 am

Some very interesting quotes from a WSJ article;

"The focus of the probe is shifting away from its early emphasis on individual system malfunctions and suspected pilot mistakes, according to people tracking developments.

Instead, these people said, U.S. and Indonesian crash investigators increasingly are delving into the way the MAX 8’s automated flight-control systems interact with each other, and how rigorously the FAA and Boeing analyzed potential hazards in the event some of them malfunction and feed incorrect or unreliable data to the plane’s computers. Swiftly turning off the automated feature is the solution in such cases.

Earlier 737 versions have different stall-protection systems, that don’t automatically drive down the nose even when other functions of the plane’s autopilot are turned off. Yet operation of those older systems was highlighted in training over the years, and pilots had to memorize steps to counteract potentially dangerous unintended consequences. MAX 8 training materials don’t include a requirement to memorize the steps to turn off the stall-protection system."

Link for the full article;
https://www.wsj.com/articles/boeing-wit ... 1542082575
 
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scbriml
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 9:03 am

N212R wrote:
One of the most important aviation threads of the year has fallen off the front page here at Airliners.

The powers that be are circling the wagons. The proverbial shite must be ready to hit the fan.


What on Earth are you on about? :confused:

MaksFly wrote:
SuseJ772 wrote:
F9Animal wrote:
I find it rather disturbing that technology to prevent an accident, hinders a crew ability to save a plane when that technology fails. Can you imagine what those pilots faced in the final moments? At such a low altitude, troubleshooting is not much of an option, especially when they couldn't maintain level flight.

As my uncle once said.... We have become too reliant on technology, and stick and rudder days are pretty much gone. A "WTF" situation on takeoff has to be pretty horrifying.
This is statistically wrong. We are at the safest time in aviation history by far. While at the same time the highest amount of automation. Yes automation can be over relied on. But is has also saved untold thousands of lives. Which we will never know that number so a comparison is useless with the data we have.


the question is however... how much of this is due to automation versus better engineering and manufacturing of aircraft.


It's not one versus the others, it's combinations of all of those pluse better knowledge of materials, massively powerful computerised designing and lots of other factors. They all contribute to making aviation safer now than it's ever been before.
Time flies like an arrow. Fruit flies like a banana!
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SteinarN
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 9:09 am

Two other quote from the same article;

"Boeing is working on a software fix, according to industry and government officials, that would likely mitigate risks. On Saturday, the company went further than before in spelling out dangers pilots can face if they misinterpret or respond too slowly to counter automated commands."

"The ultimate way to counteract dangerous automated nose-down commands is basically the same for old and new systems, though checklists and procedures for the 737 MAX 8 entail more steps and take more time. Investigators and safety experts are convinced that as the emergency worsened, the Lion Air crew had barely seconds in which they could have diagnosed the problem and taken action to save the aircraft."
 
WIederling
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 9:37 am

7BOEING7 wrote:
maint123 wrote:
Or why have a manual mode only in MAX, where the pilots will still be overridden by automation ?


The only time the pilot can be overridden with this system is if he has his hands off the controls or is pushing the nose over (then he's getting help) -- if he has his hands on the controls and has some back force (which he would if the airplane was trying to nose over) the automatic nose down trim is overridden.


IMU you are describing the NG logic and not the MAX.
MAX seems to have AoA tied into the Trim action.

And it looks like this change was done rushed.
Murphy is an optimist
 
kalvado
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 10:25 am

Starlionblue wrote:

A very basic Airbus rule on use automation goes more or less as follows:
- If a managed mode (fully automated) does not give you the expected result, use a selected mode (autoflight but manually selected parameters).
- If a selected mode does not give you the expected result either, disengage the automation and fly manually.
In other words, don't try to fiddle with the programming "on the fly". Use a lesser degree of automation, or none at all, to get the result you want. Then once the aircraft is doing what you want, re-program and re-engage as appropriate.

The automation is designed to help us, not make us helpless.

The assumption behind this approach is that the plane can fly with all automation off (and as far as I remember, 320 series can somewhat fly with just some manual controls and no power at all as the last fallback mode. Static stability of the airframe is one of the requirements for such all-manual operation. And, as I learned from this thread, static stability is required by FAR for civilian aircraft.
Modern warplanes, as far as I know, are inheritingly unstable to achieve better maneuverability. So total power loss to control system means plane becomes uncontrollable as a straight flight cannot be maintained manually- and ejection seat becomes the fallback operation mode.
Now, what I hear here, is Boeing traded in most of the static stability for extra fuel savings. To achieve dynamic stability, they had to make stabilizer bigger - but instead of making it physically bigger, they made it bigger in aerodynamic sense by adding automated movements. And inhibiting those movements, in principle, may end up with envelope shrinkage - possibly down to no flyable window (we don't have details, though, likely things are not that bad). So turning off ALL automation may no longer be an option - as it is not an option on fighter planes.
Now since system kicks in manual flight (I assume same logic is integrated into autopilot anyway) when things are possibly not that good anymore - then the logic of the system has to be bulletproof, not an afterthought as it feels from whatever information is available.

This is not first time automation is the only way to go. Apollo landing on Moon was done automatically until the last seconds of the flight, since manual handling is almost impossible. As far as I know there was only one successfull manual sim landing. Now 737 is not exactly Apollo spacecraft.
 
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Starlionblue
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 10:26 am

kalvado wrote:
Starlionblue wrote:

A very basic Airbus rule on use automation goes more or less as follows:
- If a managed mode (fully automated) does not give you the expected result, use a selected mode (autoflight but manually selected parameters).
- If a selected mode does not give you the expected result either, disengage the automation and fly manually.
In other words, don't try to fiddle with the programming "on the fly". Use a lesser degree of automation, or none at all, to get the result you want. Then once the aircraft is doing what you want, re-program and re-engage as appropriate.

The automation is designed to help us, not make us helpless.

The assumption behind this approach is that the plane can fly with all automation off (and as far as I remember, 320 series can somewhat fly with just some manual controls and no power at all as the last fallback mode. Static stability of the airframe is one of the requirements for such all-manual operation. And, as I learned from this thread, static stability is required by FAR for civilian aircraft.
Modern warplanes, as far as I know, are inheritingly unstable to achieve better maneuverability. So total power loss to control system means plane becomes uncontrollable as a straight flight cannot be maintained manually- and ejection seat becomes the fallback operation mode.
Now, what I hear here, is Boeing traded in most of the static stability for extra fuel savings. To achieve dynamic stability, they had to make stabilizer bigger - but instead of making it physically bigger, they made it bigger in aerodynamic sense by adding automated movements. And inhibiting those movements, in principle, may end up with envelope shrinkage - possibly down to no flyable window (we don't have details, though, likely things are not that bad). So turning off ALL automation may no longer be an option - as it is not an option on fighter planes.
Now since system kicks in manual flight (I assume same logic is integrated into autopilot anyway) when things are possibly not that good anymore - then the logic of the system has to be bulletproof, not an afterthought as it feels from whatever information is available.

This is not first time automation is the only way to go. Apollo landing on Moon was done automatically until the last seconds of the flight, since manual handling is almost impossible. As far as I know there was only one successfull manual sim landing. Now 737 is not exactly Apollo spacecraft.


Nice analysis. And quite some food for thought.
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
mjoelnir
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 10:47 am

https://www.seattletimes.com/business/b ... e_left_1.1

Has this article from the Seattle Times been posted yet?

I think the situation is growing sticky for Boeing.
 
mjoelnir
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 10:54 am

PlanesNTrains wrote:
maint123 wrote:
VS11 wrote:
"Southwest, American pilots unions question 737 Max documentation after Indonesia crash"

"Two U.S. pilots' unions say the potential risks of a safety feature on Boeing Co.'s 737 Max aircraft that has been linked to a deadly crash in Indonesia weren't sufficiently spelled out in their manuals or training.

Boeing and the Federal Aviation Administration issued directives last week telling flight crews about the system, which is designed to provide extra protection against pilots losing control. That prompted aviators, unions and training departments to realize that none of the documentation for the Max aircraft included an explanation of the system, the union leaders said."

https://www.dallasnews.com/business/air ... esia-crash


Exactly what I have been stressing but a lot of circling of the wagons on this site.
All Max planes should be grounded until thorough inspection of the Max series is completed.
Their should be a investigation of both Boeing as well as the US certifying body, they seem too closely entwined.


Just curious what the grounding is for? What would they be looking for? Usually groundings seem to be done when there is an imminent threat or known defect that is of such a level of danger that continuing to fly the aircraft would be out of the question. In this case, regardless of whether Boeing handled it appropriately or not, there appears to be a fairly simple fix via better training materials and communication. Unless there is something that can be pointed to that would make flying the aircraft unacceptable, I don't see what a grounding would accomplish?


Grounding is done when effects are unknown. Boeing did not even think that training on a new system was necessary. Does the system behave to Boeings expectations, or are failure modes at work that Boeing did not test for?
Last edited by mjoelnir on Tue Nov 13, 2018 11:07 am, edited 1 time in total.
 
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PixelFlight
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 11:04 am

kalvado wrote:
Now, what I hear here, is Boeing traded in most of the static stability for extra fuel savings. To achieve dynamic stability, they had to make stabilizer bigger - but instead of making it physically bigger, they made it bigger in aerodynamic sense by adding automated movements. And inhibiting those movements, in principle, may end up with envelope shrinkage - possibly down to no flyable window (we don't have details, though, likely things are not that bad). So turning off ALL automation may no longer be an option - as it is not an option on fighter planes.
Now since system kicks in manual flight (I assume same logic is integrated into autopilot anyway) when things are possibly not that good anymore - then the logic of the system has to be bulletproof, not an afterthought as it feels from whatever information is available.

This is not first time automation is the only way to go. Apollo landing on Moon was done automatically until the last seconds of the flight, since manual handling is almost impossible. As far as I know there was only one successfull manual sim landing. Now 737 is not exactly Apollo spacecraft.


Using fighter and space dynamic stability technology require not only automation but very reliable airspeed and AoA data. This level of reliability is not possible with the old obsolete arbitration design that select between a set of sensors. The civil aircraft industry must replace it with multiple sources merger/filter with predictor and probability estimator (sensor fusion techniques). The increase of automation make the air data path more critical than before for the safety.
: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:
 
o0OOO0oChris
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 11:59 am

I think kalvado`s analysis and this quote of the Seattle Times article ist especially interesting:
A former Boeing executive, speaking on condition of anonymity because discussion of accident investigations is supposed to be closely held, said that Boeing engineers didn’t introduce the change to the flight-control system arbitrarily.

He said it was done primarily because the much bigger engines on the MAX changed the aerodynamics of the jet and shifted the conditions under which a stall could happen. That required further stall protection be implemented to certify the jet as safe.

If I understand this correctly, due to the bigger engines and their placement more infront of the wing for ground clearance issues lead to a different, worsened stall behaviour compared to the NG. To counter that effect, the MCAS system is supposed to aid the pilots, only trained in the NG behaviour, in a stall situation.

So turning it off, a pilot is confronted with a plane behaving worse than trained in the simulator in a stall condition, unprepared.

I think airbus pilots are trained a lot for the different flying characteristics in alternate mode, for good reasons. They have to be prepared in case the automation aids are not working.

For boeing introducing such an automated flight characteristics manipulation system to the new iteration of a proven plane without training the pilots on how to fly without it- jet not even telling pilots it`s there it is unbelievable.
 
runway23
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 12:04 pm

rocketPower wrote:
This whole situation amplifies the too comfortable relationship between the FAA and Boeing.

This is not just my opinion but that of many on the inside of the industry.


You can bet that had this been an A321neo or CSeries they would have been grounded by the FAA faster than it took me to write this.
 
WIederling
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 12:18 pm

runway23 wrote:
rocketPower wrote:
This whole situation amplifies the too comfortable relationship between the FAA and Boeing.

This is not just my opinion but that of many on the inside of the industry.


You can bet that had this been an A321neo or CSeries they would have been grounded by the FAA faster than it took me to write this.


And the crew would have been deemed valiant heroes, 100% blame on the manufacturer.
Here it is illiterate monkey crew and Boeing Uber Alles.
Murphy is an optimist
 
juliuswong
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 12:23 pm

Oh no, does this actually mean Boeing pushed a product into the market without proper training procedures being put in place (operating manual)?? Too early to conclude?
- Life is a journey, travel it well -
 
StTim
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 12:36 pm

juliuswong wrote:
Oh no, does this actually mean Boeing pushed a product into the market without proper training procedures being put in place (operating manual)?? Too early to conclude?


Way too early to conclude - but the information seeping out is looking worse and worse for Boeing and the FAA.
 
rocketPower
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 12:54 pm

Finn350 wrote:
As some have stated earlier, 737 as a whole is a legacy design and implementing FBW and envelope protection features in 737MAX is prone to flaws.


This.

In no way a modern commercial airliner would be allowed to be certified with a single sensor manipulating the control path in a manner that is hazardous or catastrophic. You would need multiple sensors such that you meet the integrity and availability required by the user functions. Not only that you'd be slammed with an issue paper forcing you to minimize common cause effects causing the majority of your sensors to propagate similar, erroneous data... especially after AF447.

Even if all that could theoretically be met with one sensor, you would need to test its failure modes and resulting effects on controllability.

How did all this pass through undetected?
rocketPower

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scbriml
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 1:14 pm

runway23 wrote:
You can bet that had this been an A321neo or CSeries they would have been grounded by the FAA faster than it took me to write this.


This is patently nonsense.

Were A330s grounded after AF447?

Were A320s grounded after QS8501?
Time flies like an arrow. Fruit flies like a banana!
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mjoelnir
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 1:14 pm

[twoid][/twoid]
StTim wrote:
juliuswong wrote:
Oh no, does this actually mean Boeing pushed a product into the market without proper training procedures being put in place (operating manual)?? Too early to conclude?


Way too early to conclude - but the information seeping out is looking worse and worse for Boeing and the FAA.


It is way to early to conclude what exactly happend at the crash. It is not to early to conclude, that there are serious issues with flight training and documentation for the MAX and that is the responsibility of Boeing and the FAA.
 
runway23
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 1:20 pm

scbriml wrote:
runway23 wrote:
You can bet that had this been an A321neo or CSeries they would have been grounded by the FAA faster than it took me to write this.


This is patently nonsense.

Were A330s grounded after AF447?

Were A320s grounded after QS8501?


Were either aircraft types that crashed recently put (rushed) into service ? Answer is no. 737Max was rushed through certification on the premise that everything was similar to 737NGs, yet Boeing made significant changes and failed to advise its customers. Such changes should have been discovered by the FAA during certification.
 
YOWVIEWER
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 1:40 pm

Would love to hear from anyone at Air Canada or Westjet regarding this latest news and training for pilots on their fleet of Max aircraft.
 
maint123
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 1:43 pm

rocketPower wrote:
Finn350 wrote:
As some have stated earlier, 737 as a whole is a legacy design and implementing FBW and envelope protection features in 737MAX is prone to flaws.


This.

In no way a modern commercial airliner would be allowed to be certified with a single sensor manipulating the control path in a manner that is hazardous or catastrophic. You would need multiple sensors such that you meet the integrity and availability required by the user functions. Not only that you'd be slammed with an issue paper forcing you to minimize common cause effects causing the majority of your sensors to propagate similar, erroneous data... especially after AF447.

Even if all that could theoretically be met with one sensor, you would need to test its failure modes and resulting effects on controllability.

How did all this pass through undetected?

FAA issued its notification immediately after Boeing had given its recommendation. Isn't FAA supposed to independently verify the manufactures product/processes ?
Boeing can make mistakes like any other company but its the FAA's responsibility to verify the changes.
 
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Starlionblue
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 1:49 pm

maint123 wrote:
rocketPower wrote:
Finn350 wrote:
As some have stated earlier, 737 as a whole is a legacy design and implementing FBW and envelope protection features in 737MAX is prone to flaws.


This.

In no way a modern commercial airliner would be allowed to be certified with a single sensor manipulating the control path in a manner that is hazardous or catastrophic. You would need multiple sensors such that you meet the integrity and availability required by the user functions. Not only that you'd be slammed with an issue paper forcing you to minimize common cause effects causing the majority of your sensors to propagate similar, erroneous data... especially after AF447.

Even if all that could theoretically be met with one sensor, you would need to test its failure modes and resulting effects on controllability.

How did all this pass through undetected?

FAA issued its notification immediately after Boeing had given its recommendation. Isn't FAA supposed to independently verify the manufactures product/processes ?
Boeing can make mistakes like any other company but its the FAA's responsibility to verify the changes.


My uninformed guess is that the FAA was already on site at Boeing, and vetted the notification before it was even published.
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
Airbuser
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 2:08 pm

There is a huge push mandated by the FAA to get back to hand flying. I recently had the first scenario in my recurrent training. It was a complex RNAV departure with no auto thrust or auto pilot. Multiple speed changes and at or above in betweens and at or belows in the departure. To me it was way beneath my experience level and clearly designed for the next generation of pilots. I have done this particular departure many times. Every time I have done this departure it has been hand flown. It’s fun. I am often surprised how soon many pilots I fly with turn the automation on. They are usually surprised when I turn it all off on approach. The automation is great but it doesn’t always do what you think it’s going to do. Understand it, use it, never trust it. Some day it may not work.

If you have taken the tours at Airbus or Boeing they brag about how easy it is to fly their airplanes. True if it all works. Not true when it breaks. I used to sell Cessna aircraft. I would fly the airplane never touching the yoke. Rudders and trim. See how easy it is? It’s flying itself.
 
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PixelFlight
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 2:13 pm

rocketPower wrote:
In no way a modern commercial airliner would be allowed to be certified with a single sensor manipulating the control path in a manner that is hazardous or catastrophic. You would need multiple sensors such that you meet the integrity and availability required by the user functions. Not only that you'd be slammed with an issue paper forcing you to minimize common cause effects causing the majority of your sensors to propagate similar, erroneous data... especially after AF447.

Even if all that could theoretically be met with one sensor, you would need to test its failure modes and resulting effects on controllability.

How did all this pass through undetected?


That exactly where the next part of the debate must go: air (speed & AoA) data reliability and safety assessment activity. Sensors could give incorrect values or fail, this the real unavoidable fact. The old school arbitration design is not appropriate anymore for critical automation required by unstable dynamic. New design must use predictors that process data fusion from many different sensors types. This technology already exists and must be required by the safety authorities.
: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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trpmb6
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 2:17 pm

Am I wrong in saying that additional training was still not really required? No matter the cause of the situation, it's still a runaway trim issue correct? So the solution is still the same as existing training when runaway trim situations occur.
 
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PixelFlight
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 2:21 pm

o0OOO0oChris wrote:
If I understand this correctly, due to the bigger engines and their placement more infront of the wing for ground clearance issues lead to a different, worsened stall behaviour compared to the NG. To counter that effect, the MCAS system is supposed to aid the pilots, only trained in the NG behaviour, in a stall situation.

So turning it off, a pilot is confronted with a plane behaving worse than trained in the simulator in a stall condition, unprepared.

Can anyone share what it's like to aviate a 737MAX with MCAS tunrned off ?
: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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Erebus
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 2:41 pm

kalvado wrote:
Now, what I hear here, is Boeing traded in most of the static stability for extra fuel savings. To achieve dynamic stability, they had to make stabilizer bigger - but instead of making it physically bigger, they made it bigger in aerodynamic sense by adding automated movements. And inhibiting those movements, in principle, may end up with envelope shrinkage - possibly down to no flyable window (we don't have details, though, likely things are not that bad). So turning off ALL automation may no longer be an option - as it is not an option on fighter planes.


Would this decrease in stability be more pronounced in any of the other MAX variants?
 
Trin
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 2:52 pm

trpmb6 wrote:
Am I wrong in saying that additional training was still not really required? No matter the cause of the situation, it's still a runaway trim issue correct? So the solution is still the same as existing training when runaway trim situations occur.


I don't know. Runaway trim, sure - every PF should know how to deal with that with it being a standard memory item. Question would be did Boeing put the MAX through enough rigorous testing in relation to it's altered center of gravity with those massive engines, the new stab trim behavior and automation and how that would affect manual flying. Not to mention the fact that in manual mode, the aircraft will repeatedly attempt to push the nose over on you, at 10-15 second intervals, even after you wrest the controls away from it (yes I know that the crew should have cut power to this system after that but.....).

There's so much talk yesterday and today about the new MCAS on the MAX and how this would have played a part - but very little (or no) discussion any longer about the malfunctioning AoA sensors and/or erroneous airspeed indications that this particular plane had been experiencing for DAYS in the run-up to this accident, and what THAT means. I've been saying it this whole time and continue to - there was something VERY wrong with this airplane. It's not like every single flight prior to this fateful one was quiescent and uneventful - Lion Air flight crews and ground crews were ACTIVELY involved in troubleshooting and writing up erratic (nose-downs during climb out) behavior from this aircraft for DAYS prior to this flight.

We need more information. We need the CVR.

Trin
 
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Finn350
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 3:05 pm

trpmb6 wrote:
Am I wrong in saying that additional training was still not really required? No matter the cause of the situation, it's still a runaway trim issue correct? So the solution is still the same as existing training when runaway trim situations occur.


It looks very much like that the cause of the accident is a design flaw in the trim stabilizer system when there is an AoA sensor malfunction, so the training or lack of it is not really the central question here (although the conversion training for the 737MAX should include the new system used to stabilize the plane).
 
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PixelFlight
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 3:16 pm

Trin wrote:
There's so much talk yesterday and today about the new MCAS on the MAX and how this would have played a part - but very little (or no) discussion any longer about the malfunctioning AoA sensors and/or erroneous airspeed indications that this particular plane had been experiencing for DAYS in the run-up to this accident, and what THAT means. I've been saying it this whole time and continue to - there was something VERY wrong with this airplane.

I continue to say that the malfunctioning AoA sensors must not make the IADRU produce erratic or no AoA/speed values. There is technology to evaluate merge and filtering air data from predictors and different sensors types. This increase the precision even in case of an erratic sensor, and still give values is all of them fail. In that later case predicted air data don't have the same precision as the sensor, but still enough to give an alternative protection mode.
: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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scbriml
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 3:16 pm

runway23 wrote:
scbriml wrote:
runway23 wrote:
You can bet that had this been an A321neo or CSeries they would have been grounded by the FAA faster than it took me to write this.


This is patently nonsense.

Were A330s grounded after AF447?

Were A320s grounded after QS8501?


Were either aircraft types that crashed recently put (rushed) into service ? Answer is no. 737Max was rushed through certification on the premise that everything was similar to 737NGs, yet Boeing made significant changes and failed to advise its customers. Such changes should have been discovered by the FAA during certification.


Well, if you want recently put into service, try AF296 just three months after A320 EIS. No grounding.

By what measure was the 737MAX "rushed" into service? It's not the certification authorities job to "discover" things about new planes - they set the criteria and standards which the OEMs must meet and can show have met. I honestly don't know how much 'hands on' work the FAA would have done for the MAX given it's 'just another 737' (with, presumably, lots of grandfathered certifications).
Time flies like an arrow. Fruit flies like a banana!
There are 10 types of people in the World - those that understand binary and those that don't.
 
sgbroimp
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 3:24 pm

Airbuser wrote:
There is a huge push mandated by the FAA to get back to hand flying. I recently had the first scenario in my recurrent training. It was a complex RNAV departure with no auto thrust or auto pilot. Multiple speed changes and at or above in betweens and at or belows in the departure. To me it was way beneath my experience level and clearly designed for the next generation of pilots. I have done this particular departure many times. Every time I have done this departure it has been hand flown. It’s fun. I am often surprised how soon many pilots I fly with turn the automation on. They are usually surprised when I turn it all off on approach. The automation is great but it doesn’t always do what you think it’s going to do. Understand it, use it, never trust it. Some day it may not work.

If you have taken the tours at Airbus or Boeing they brag about how easy it is to fly their airplanes. True if it all works. Not true when it breaks. I used to sell Cessna aircraft. I would fly the airplane never touching the yoke. Rudders and trim. See how easy it is? It’s flying itself.


Bravo to your opinion. You didn't even get to the point that when the tech fails it can be miserable to troubleshoot and fix in a minute or so. And the more bells and whistles built in, the more that can go wrong and the longer it can take to sort out. And sometimes you do not have that long with a misbehaving aircraft. A check pilot friend for a major told me he and some other pilots asked the airline to remove some of those bells and whistles or stop ordering them.
 
PlanesNTrains
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 3:31 pm

maint123 wrote:
PlanesNTrains wrote:
maint123 wrote:

Exactly what I have been stressing but a lot of circling of the wagons on this site.
All Max planes should be grounded until thorough inspection of the Max series is completed.
Their should be a investigation of both Boeing as well as the US certifying body, they seem too closely entwined.


Just curious what the grounding is for? What would they be looking for? Usually groundings seem to be done when there is an imminent threat or known defect that is of such a level of danger that continuing to fly the aircraft would be out of the question. In this case, regardless of whether Boeing handled it appropriately or not, there appears to be a fairly simple fix via better training materials and communication. Unless there is something that can be pointed to that would make flying the aircraft unacceptable, I don't see what a grounding would accomplish?

Read what the AMERICAN pilots are saying.
1. Inadequate and negligible training.
2. No new documentation.

Also 190 odd deaths in a new unproven Boeing plane due to above .
If it was some other country, maybe a car crash , even with a couple of deaths , by now a congressional committee would be on the job, with 1000s of cars recalled.
That's why I said Boeing did a lousy job but the certifying personnel also have to be questioned.


1. They are addressing the issue by communicating immediately on what pilots need to do if faced with this same circumstance.
2. New documentation will surely be forthcoming for all carriers.
3. It will be investigated - what do we need a congressional committee for?
4. I'm not sure why you emphasize AMERICAN pilots?

Anyhow, it's a tragedy to be sure, and an investigation will reveal what happened and why. Boeing will likely bear most if not all responsibility based on the information we have so far. Hopefully the heads of whomever are responsible will roll. I'm just not clear what a grounding would accomplish?
-Dave


MAX’d out on MAX threads. If you are starting a thread, and it’s about the MAX - stop. There’s already a thread that covers it.
 
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flyingturtle
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Re: Lion Air 737MAX8 Crashed Jakarta to Pangal Pinang

Tue Nov 13, 2018 3:33 pm

Wow, the revelation that MCAS and its workings were never divulged to pilots.

"Thanks to this thingamajic, your MAX will behave as a NG. No need to understand how this thingamajic could fail. Or that it even exists."

If a MAX is marketed as "it behaves like a NG", then it must do so under all possible circumstances. Will this be a watershed event in certifying airplanes?


David
Reading accident reports is what calms me down

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