WayexTDI
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Re: Did the 737 MAX go one step too far?

Fri Dec 14, 2018 8:27 pm

B737900ER wrote:
WayexTDI wrote:

FWIW, I trust the pilots in what they are saying: the MAX is not inherently unstable, but some groups of pilots were kept in the dark(ish?) about the MCAS.

If they were kept in the dark it wasn’t by Boeing. It’s not like Boeing omitted parts of its manual to hide a design. Individual airline training programs didn’t inform their pilots. Boeing produces the flight manual and airlines teach their pilots what they feel is relevant out of it. Same with maintenance training. Airlines don’t teach the manual line by line, just the parts they think need to be highlighted.

Bottom line is Boeing doesn’t teach pilots how to fly planes. Individual airlines teach their pilots how to fly. If UA taught their pilots and AA and WN didn’t, it doesn’t mean Boeing withheld information. It means UA has better training.

I'm sorry if I insulted your beloved Boeing. :?

If the MCAS was so darn critical, don't you think Boeing should have highlighted it as such?
Not everything is critical to fly an aircraft; some things are (different speeds, different critical systems). MCAS appears to be one of them.
 
dakota123
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Re: Did the 737 MAX go one step too far?

Fri Dec 14, 2018 9:03 pm

kalvado wrote:
dakota123 wrote:
WIederling wrote:
Even longer lament.
Pilot opinion is worthless as they see the basic airframe wrapped by various enhancing systems ( including MCAS ).
Additionally they did not even know about MCAS.

Then it is not about complex computations or deeply fractal analysis.
It is all in the open.
MCAS appears to be designed to keep the plane below a distinct positive pitch up angle.
( in a rather anal retentive way )
That indicates that the stable range of attitudes ends there.
A stall recovery is deemed very difficult or even impossible.
IMU certification requirements do not allow this situation.
you can have relaxed stability ( but only in cruise?) but not positive feed back.


If that were the case, there's no way it would trim at the rather leisurely rate of 0.27 deg/sec. It would damn well shove the nose down by some method other than trim. And it wouldn't pause for five seconds when countermanded. Fice seconds is an eternity in a stalled or nearly stalled condition.

Do you have something better to add to the discussion than arguing with well established facts? It was said more than once that MCAS role is exactly that - prevent approaching to stall and upset. Why Boeing chose to do it the way they did, rates, times... Those who know it are not allowed to talk about it.


"It was said" I love it. Who said? People on here? People talking to the media? I was responding to the specific assertions made in the thread I quoted, which are nothing more than opinions at this point. My opinion is that if the stability issue were as grave as the poster makes out, there is no way that there would be such a measured response.

Cool the snarkiness. Who made you keeper of the thread exactly? Holy shite some people on here...
“And If I claim to be a wise man, well surely it means that I don’t know”
 
kalvado
Posts: 1892
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Re: Did the 737 MAX go one step too far?

Fri Dec 14, 2018 9:26 pm

dakota123 wrote:
kalvado wrote:
dakota123 wrote:

If that were the case, there's no way it would trim at the rather leisurely rate of 0.27 deg/sec. It would damn well shove the nose down by some method other than trim. And it wouldn't pause for five seconds when countermanded. Fice seconds is an eternity in a stalled or nearly stalled condition.

Do you have something better to add to the discussion than arguing with well established facts? It was said more than once that MCAS role is exactly that - prevent approaching to stall and upset. Why Boeing chose to do it the way they did, rates, times... Those who know it are not allowed to talk about it.


"It was said" I love it. Who said? People on here? People talking to the media? I was responding to the specific assertions made in the thread I quoted, which are nothing more than opinions at this point. My opinion is that if the stability issue were as grave as the poster makes out, there is no way that there would be such a measured response.

Cool the snarkiness. Who made you keeper of the thread exactly? Holy shite some people on here...

Let me keep it technical. Did you read Leeham article on MCAS? From there, you can either argue that Leeham is incorrect in their comments (and that is quite a bold step); or accept their assertion of the issue. If you think Leeham is incorrect, you better have some better argument than "I think".
 
B737900ER
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Re: Did the 737 MAX go one step too far?

Fri Dec 14, 2018 10:10 pm

WayexTDI wrote:

If the MCAS was so darn critical, don't you think Boeing should have highlighted it as such?
Not everything is critical to fly an aircraft; some things are (different speeds, different critical systems). MCAS appears to be one of them.

Who’s to say they didn’t highlight it to the operators. Boeing, Airbus, or however builds the planes don’t train airline pilots. Apparently only one operator thought it was critical enough to alert their pilots.

Don’t take it so personal. That’s how the industry works. The emotion on here over multinational corporations and machinery is mind blowing.
 
WIederling
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Re: Did the 737 MAX go one step too far?

Fri Dec 14, 2018 10:11 pm

dakota123 wrote:
My opinion is that if the stability issue were as grave as the poster makes out, there is no way that there would be such a measured response.


The 787 battery issues culminated in a grounding only after a US plane was involved.
Afair the same applied to the MD10 and its design issues?
Murphy is an optimist
 
B737900ER
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Joined: Thu Aug 31, 2006 10:26 am

Re: Did the 737 MAX go one step too far?

Fri Dec 14, 2018 10:23 pm

glideslope wrote:
In my opinion I have no reason to not fly a Max with a carrier that follows procedures, and has the correct training/maintenance procedures implemented as required.

This x 1000
Speaking for major US based airlines, an aircraft that experiences a flight control problem, or instrument discrepancy, or any other major safety of flight problem, is taken out of service until the repair is confirmed. Not just oh I think I fixed it. Lion air failed at that four times. They flew an airplane with a broken flight control system for four flights. Airbus, Boeing, SQ, DL, whoever, bad things will happen if you do that.
 
1989worstyear
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Re: Did the 737 MAX go one step too far?

Sat Dec 15, 2018 1:15 am

WIederling wrote:
dakota123 wrote:
My opinion is that if the stability issue were as grave as the poster makes out, there is no way that there would be such a measured response.


The 787 battery issues culminated in a grounding only after a US plane was involved.
Afair the same applied to the MD10 and its design issues?


AA flight 96 actually happened a couple years before THY 981, if you're referring to the defective cargo door.
Stuck at age 15 thanks to the certification date of the A320-200 and my parents' decision to postpone having a kid by 3 years. At least there's Dignitas...
 
JoeCanuck
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Re: Did the 737 MAX go one step too far?

Sat Dec 15, 2018 1:47 am

WIederling wrote:
dakota123 wrote:
My opinion is that if the stability issue were as grave as the poster makes out, there is no way that there would be such a measured response.


The 787 battery issues culminated in a grounding only after a US plane was involved.
Afair the same applied to the MD10 and its design issues?


No air safety agency on the planet has grounded the MAX and they have access to a lot more information than we do.

EASA, for instance, doesn't need the FAA's permission to ground any aircraft in European airspace. So far, they haven't so they must consider the MAX safe enough to fly on.

Not even Airbus is calling for the MAX to be grounded. I have no doubt some things on the MAX do need fixing, but it seems everything is pretty much under control...except on A.net.
What the...?
 
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NeBaNi
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Re: Did the 737 MAX go one step too far?

Sat Dec 15, 2018 2:01 am

JoeCanuck wrote:
WIederling wrote:
dakota123 wrote:
My opinion is that if the stability issue were as grave as the poster makes out, there is no way that there would be such a measured response.


The 787 battery issues culminated in a grounding only after a US plane was involved.
Afair the same applied to the MD10 and its design issues?


No air safety agency on the planet has grounded the MAX and they have access to a lot more information than we do.

EASA, for instance, doesn't need the FAA's permission to ground any aircraft in European airspace. So far, they haven't so they must consider the MAX safe enough to fly on.

Not even Airbus is calling for the MAX to be grounded. I have no doubt some things on the MAX do need fixing, but it seems everything is pretty much under control...except on A.net.

I'm not sure Airbus would ever call for a MAX grounding, and I'd say the same for Boeing if an Airbus aircraft was involved in a crash like that. OEMs should not (and imo will not) ever call for their competitors' products to be grounded.
 
kalvado
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Re: Did the 737 MAX go one step too far?

Sat Dec 15, 2018 2:23 am

NeBaNi wrote:
JoeCanuck wrote:
WIederling wrote:

The 787 battery issues culminated in a grounding only after a US plane was involved.
Afair the same applied to the MD10 and its design issues?


No air safety agency on the planet has grounded the MAX and they have access to a lot more information than we do.

EASA, for instance, doesn't need the FAA's permission to ground any aircraft in European airspace. So far, they haven't so they must consider the MAX safe enough to fly on.

Not even Airbus is calling for the MAX to be grounded. I have no doubt some things on the MAX do need fixing, but it seems everything is pretty much under control...except on A.net.

I'm not sure Airbus would ever call for a MAX grounding, and I'd say the same for Boeing if an Airbus aircraft was involved in a crash like that. OEMs should not (and imo will not) ever call for their competitors' products to be grounded.

To make a substantiated call for grounding, one needs pretty full access to certification documentation. I doubt those are public domain and released to the competitor on demand.
 
JoeCanuck
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Re: Did the 737 MAX go one step too far?

Sat Dec 15, 2018 2:57 am

It's the twitter age. Nothing has to be substantiated...it just has to trend. :chat:
What the...?
 
AvObserver
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Re: Did the 737 MAX go one step too far?

Sat Dec 15, 2018 3:54 am

kalvado wrote:
AvObserver wrote:
Amiga500 wrote:

I see in this (and subsequent posts) that you believe the sky-gods in the front to be infallible sources of knowledge on aircraft design and flight performance.

Would you be so quick to take the word of a taxi driver on how the engine ECU works over the word of an engineer that has designed said ECUs?

I'll repeat what I said:

"If it does not return from a non-stalled and within envelope positive angle of attack then it is longitudinally statically unstable by standard definitions of flight dynamics."

It is not my definition of flight dynamics that I am using - its industry standard. Furthermore, if the MAX was a completely stable aircraft throughout the flight envelope - then it wouldn't need the MCAS - unless you think Boeing doesn't know that the MAX is actually stable either?

prebennorholm makes a good point about relaxed stability - but if the MAX were relaxed stability to the point active control input is required to prevent departure from controlled flight - then while the static margin may be (just) negative aka stable and all is hunky dory on paper - its not really a stable aircraft.

At such edge of envelope conditions - performance can be so sensitive to outside perturbations at that condition that an adverse gust (for example) can lead to unstable conditions and departure from controlled flight. Hence why Boeing added the MCAS as a fudge around it - and cut more than a few corners putting it together.

As said above by prebennorholm as well - how a primary flight control system is allowed to be driven off one sensor is shocking in this day and age. How that isn't in large capital bolded red writing all over the FCOM is also unbelievable. Boeing have really had a dereliction of duty here.

I may be barking up the wrong tree - but it sounds like the powerpoint mafia and wordsmiths have "mitigated" their way out of paying for a solution (in terms of money, time and resource) by dancing around with words - and now nearly 200 people are dead because of it. Undue pressure from people that aren't knowledgeable enough to know better dictating over those that are is likely the root cause. Its a curse on engineering and not limited to any particular company, country or continent.

Again, all of the facts are not in so it's still way to early to make such conclusions. You assume MCAS is needed to mitigate stability issues. How do you know why MCAS was added? Do you have a mole working at Boeing? And as for your definition: "If it does not return from a non-stalled and within envelope positive angle of attack then it is longitudinally statically unstable by standard definitions of flight dynamics." Do you know for certain this is what happened? Quite frankly, when you say don't take the pilots' word over an engineer's word, what do you know about the engineering of this airplane? Have the engineers come and indicted this design for instability? One thing at least I'd agree on, the MCAS itself may need to be fixed and that is a design issue, albeit probably one that won't take a great deal of time to remedy once they determine how the AOA sensors may have tripped it up. And it's still entirely possible that Lion Air's maintenance may have been complicit in the crash although, heaven forbid, I'm not ready to pronounce them guilty either. Boeing may have a faulty FCS though that too has yet to be proven and there's no denying they erred mightily in not properly announcing and documenting it for the pilots. That error is likely worth a big upcoming fine and possible loss of near-term sales campaigns but the pilots, assuming they're not imposters, are saying the MAX is stable in flight. So as I see it, you too are making a broad assumption which is a bridge too far. Perhaps you too could post some intricate data on just why the 737 MAX is "longitudinally statically unstable" and prove just why all of those assumed MAX pilots are so wrong when they insist it is stable. Enlighten us all!

This all started from the Leeham article on MCAS, and I was the one to bring up the instability issue here.
Leeham gives a (IMHO very plausible) explanation of instability mechanisms and reasons MCAS was implemented.
If you want argue - go find the article, read it, and then we may talk.


https://leehamnews.com/2018/12/14/bjorn ... ty-part-4/ If this is the article you are referring to, it's not giving a conclusion. I checked the earlier installment and found nothing about fundamental instability of 737 MAX. In fact, I see "The MAX will have acceptable pitch stability margins when loaded at the aft limit of 35% MAC when taking off with 150,000lb or 68t. And it can still control the aircraft in pitch fast enough for takeoff when it’s loaded nose heavy at 12% of MAC for the same weight. At landing at a lower weight, the allowed forward CG is even wider. The aft limit is then a bit less. This is normal, there is less weight working on the pitch stability moment arm between center of lift and CG. The diagram is not unique to the MAX, other airliner diagrams are similar." If this is not the article you are referring to then please post the one you are referring to because I see nothing here that flat out says the 737 MAX has a flight stability problem.
 
AvObserver
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Re: Did the 737 MAX go one step too far?

Sat Dec 15, 2018 4:06 am

kalvado wrote:
dakota123 wrote:
kalvado wrote:
Do you have something better to add to the discussion than arguing with well established facts? It was said more than once that MCAS role is exactly that - prevent approaching to stall and upset. Why Boeing chose to do it the way they did, rates, times... Those who know it are not allowed to talk about it.


"It was said" I love it. Who said? People on here? People talking to the media? I was responding to the specific assertions made in the thread I quoted, which are nothing more than opinions at this point. My opinion is that if the stability issue were as grave as the poster makes out, there is no way that there would be such a measured response.

Cool the snarkiness. Who made you keeper of the thread exactly? Holy shite some people on here...

Let me keep it technical. Did you read Leeham article on MCAS? From there, you can either argue that Leeham is incorrect in their comments (and that is quite a bold step); or accept their assertion of the issue. If you think Leeham is incorrect, you better have some better argument than "I think".

Here's the one that references MCAS: https://leehamnews.com/2018/11/30/bjorn ... ty-part-2/ Again, where is the specific complaint that the 737 MAX is fundamentally unstable? According to the analysis presented here, that could be said of other modern airliners as well.
 
AvObserver
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Re: Did the 737 MAX go one step too far?

Sat Dec 15, 2018 4:24 am

WIederling wrote:
AvObserver wrote:
And you have the nerve to say that the opinions of MAX pilots who've chimed in here have no relevance. .................

Even longer lament.
Pilot opinion is worthless as they see the basic airframe wrapped by various enhancing systems ( including MCAS ).
Additionally they did not even know about MCAS.

Then it is not about complex computations or deeply fractal analysis.
It is all in the open.
MCAS appears to be designed to keep the plane below a distinct positive pitch up angle.
( in a rather anal retentive way )
That indicates that the stable range of attitudes ends there.
A stall recovery is deemed very difficult or even impossible.
IMU certification requirements do not allow this situation.
you can have relaxed stability ( but only in cruise?) but not positive feed back.

Still mostly supposition and innuendo on your part. So far the evidence points to issues with the AOA sensors linking to the MCAS and maybe a software problem with the MCAS itself. It does not point to a a basic flight stability issue with the MAX when pilots say if they had such an issue would turn off the MCAS and fly the airplane manually. If they'd do that, it can't be all that unstable. It may well have relaxed stability compared to the NG but it's still just conjecture that the MCAS was added specifically to deal with that. And the pilots' opinions may not be the final word but they are far from worthless. Of more value than the armchair "experts" like you who weren't in on the design and engineering, let alone flight training. Amazing how sure of yourself you are with so few facts backing you up.
 
kalvado
Posts: 1892
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Re: Did the 737 MAX go one step too far?

Sat Dec 15, 2018 11:19 am

AvObserver wrote:
kalvado wrote:
dakota123 wrote:

"It was said" I love it. Who said? People on here? People talking to the media? I was responding to the specific assertions made in the thread I quoted, which are nothing more than opinions at this point. My opinion is that if the stability issue were as grave as the poster makes out, there is no way that there would be such a measured response.

Cool the snarkiness. Who made you keeper of the thread exactly? Holy shite some people on here...

Let me keep it technical. Did you read Leeham article on MCAS? From there, you can either argue that Leeham is incorrect in their comments (and that is quite a bold step); or accept their assertion of the issue. If you think Leeham is incorrect, you better have some better argument than "I think".

Here's the one that references MCAS: https://leehamnews.com/2018/11/30/bjorn ... ty-part-2/ Again, where is the specific complaint that the 737 MAX is fundamentally unstable? According to the analysis presented here, that could be said of other modern airliners as well.

In either case, I am taking the credit for making sure you at least read some professional opinions about the situation.
ANd I am talking about a different piece: https://leehamnews.com/2018/11/14/boein ... he-pilots/
Yes, that describes an instability in a certain corner of the flight envelope. Fundamental instability? I don't know if that is the appropriate term.
Yes, it takes some pilot's determination to even get to that corner, as pilots are explicitly trained NOT to get there, recognize the condition and back out into the greener pastures.. Any talk about "disabling MCAS and hand flying" is meaningless, MCAS is a last ditch effort to save the plane and make a difference between a reportable accident and an actual crash.
Boeing is correct in saying regular pilot would never know about MCAS (properly functional MCAS at least) and lack of MCAS training IMHO is not totally unreasonable (although likely illegal - but that is a different story). Properly is the keyword, though.
Now an issue of what happens in that corner of the flight envelope got a life of its own. It is not directly related to Lion crash - but it was brought into a spotlight by the crash; and it is an interesting part of this "too far" discussion. Of course, it is interesting as long as we keep it technical, and maybe legal - not fanboy or emotions.
 
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notaxonrotax
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Re: Did the 737 MAX go one step too far?

Sat Dec 15, 2018 11:26 am

Apparently pilots were never too excited about the cramped cockpit and excessive windnoise.

Has Boeing been able to tackle these issues for the MAX, perhaps by modifying the seating arrangement or the instruments a touch?

No Tax On Rotax
For anybody that happens to be wondering:"yes, owning your own aircraft is a 100% worth it!"
 
WayexTDI
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Re: Did the 737 MAX go one step too far?

Sat Dec 15, 2018 4:08 pm

B737900ER wrote:
WayexTDI wrote:

If the MCAS was so darn critical, don't you think Boeing should have highlighted it as such?
Not everything is critical to fly an aircraft; some things are (different speeds, different critical systems). MCAS appears to be one of them.

Who’s to say they didn’t highlight it to the operators. Boeing, Airbus, or however builds the planes don’t train airline pilots. Apparently only one operator thought it was critical enough to alert their pilots.

Don’t take it so personal. That’s how the industry works. The emotion on here over multinational corporations and machinery is mind blowing.

Absolutely. Your need to make sure to mention UA was trained is absolutely mind blowing.
 
AvObserver
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Joined: Sat Apr 06, 2002 7:40 am

Re: Did the 737 MAX go one step too far?

Sun Dec 16, 2018 2:48 am

[quote="kalvado
In either case, I am taking the credit for making sure you at least read some professional opinions about the situation.
ANd I am talking about a different piece: https://leehamnews.com/2018/11/14/boein ... he-pilots/
Yes, that describes an instability in a certain corner of the flight envelope. Fundamental instability? I don't know if that is the appropriate term.
Yes, it takes some pilot's determination to even get to that corner, as pilots are explicitly trained NOT to get there, recognize the condition and back out into the greener pastures.. Any talk about "disabling MCAS and hand flying" is meaningless, MCAS is a last ditch effort to save the plane and make a difference between a reportable accident and an actual crash.
Boeing is correct in saying regular pilot would never know about MCAS (properly functional MCAS at least) and lack of MCAS training IMHO is not totally unreasonable (although likely illegal - but that is a different story). Properly is the keyword, though.
Now an issue of what happens in that corner of the flight envelope got a life of its own. It is not directly related to Lion crash - but it was brought into a spotlight by the crash; and it is an interesting part of this "too far" discussion. Of course, it is interesting as long as we keep it technical, and maybe legal - not fanboy or emotions.[/quote]
Bjorn needs to cite his sources for the so-called facts he cites here. Most of this info. would surely have to have come from Boeing itself yet I don't see them or anyone else listed as a source. When he cites that the engines have been placed ahead of the CG line (comparing the MAX to the NG) how does he know that Boeing didn't relocate some systems aft to compensate for this and rebalance the aircraft to a point at least? And while the larger engines could surely alter the flight and pitch characteristics in rough maneuvers, affecting pitch stability, it doesn't sound as if it makes the MAX "fundamentally unstable", as was claimed by certain posters. Still, Bjorn and Leeham need to cite whatever sources were used to substantiate this article, otherwise it appears as if Bjorn is also making assumptions about the MAX that seemingly only Boeing insiders would know with certainty. I would still like to hear Boeing's exact statement for the rationale behind the MCAS. One indisputable fact as I see it though is that the pilots should have known all there is to know about the MCAS and that Boeing and the FAA are seemingly complicit in ensuring its existence wasn't properly disclosed to them.
 
kalvado
Posts: 1892
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Re: Did the 737 MAX go one step too far?

Sun Dec 16, 2018 3:44 pm

AvObserver wrote:
[quote="kalvado]
In either case, I am taking the credit for making sure you at least read some professional opinions about the situation.
ANd I am talking about a different piece: https://leehamnews.com/2018/11/14/boein ... he-pilots/
Yes, that describes an instability in a certain corner of the flight envelope. Fundamental instability? I don't know if that is the appropriate term.
Yes, it takes some pilot's determination to even get to that corner, as pilots are explicitly trained NOT to get there, recognize the condition and back out into the greener pastures.. Any talk about "disabling MCAS and hand flying" is meaningless, MCAS is a last ditch effort to save the plane and make a difference between a reportable accident and an actual crash.
Boeing is correct in saying regular pilot would never know about MCAS (properly functional MCAS at least) and lack of MCAS training IMHO is not totally unreasonable (although likely illegal - but that is a different story). Properly is the keyword, though.
Now an issue of what happens in that corner of the flight envelope got a life of its own. It is not directly related to Lion crash - but it was brought into a spotlight by the crash; and it is an interesting part of this "too far" discussion. Of course, it is interesting as long as we keep it technical, and maybe legal - not fanboy or emotions.[/quote]
Bjorn needs to cite his sources for the so-called facts he cites here. Most of this info. would surely have to have come from Boeing itself yet I don't see them or anyone else listed as a source. When he cites that the engines have been placed ahead of the CG line (comparing the MAX to the NG) how does he know that Boeing didn't relocate some systems aft to compensate for this and rebalance the aircraft to a point at least? And while the larger engines could surely alter the flight and pitch characteristics in rough maneuvers, affecting pitch stability, it doesn't sound as if it makes the MAX "fundamentally unstable", as was claimed by certain posters. Still, Bjorn and Leeham need to cite whatever sources were used to substantiate this article, otherwise it appears as if Bjorn is also making assumptions about the MAX that seemingly only Boeing insiders would know with certainty. I would still like to hear Boeing's exact statement for the rationale behind the MCAS. One indisputable fact as I see it though is that the pilots should have known all there is to know about the MCAS and that Boeing and the FAA are seemingly complicit in ensuring its existence wasn't properly disclosed to them.[/quote]

So called facts?
Someone seems to grasp all the straws...
Yes, this is not an official statement from Boeing - but it is a very plausible explanation IMHO, and it matches with all available information.
 
Ufsatp
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Re: Did the 737 MAX go one step too far?

Sun Dec 16, 2018 5:13 pm

WayexTDI wrote:
B737900ER wrote:
WayexTDI wrote:

If the MCAS was so darn critical, don't you think Boeing should have highlighted it as such?
Not everything is critical to fly an aircraft; some things are (different speeds, different critical systems). MCAS appears to be one of them.

Who’s to say they didn’t highlight it to the operators. Boeing, Airbus, or however builds the planes don’t train airline pilots. Apparently only one operator thought it was critical enough to alert their pilots.

Don’t take it so personal. That’s how the industry works. The emotion on here over multinational corporations and machinery is mind blowing.

Absolutely. Your need to make sure to mention UA was trained is absolutely mind blowing.


It kind of proves that Boeing did tell the airlines about it. If the other airlines didn’t feel the need to pass it along to their pilots...
 
WIederling
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Re: Did the 737 MAX go one step too far?

Sun Dec 16, 2018 5:30 pm

Ufsatp wrote:
It kind of proves that Boeing did tell the airlines about it. If the other airlines didn’t feel the need to pass it along to their pilots...

Nothing says Boeing was the active part.

It could as well have been a surprise find by that airlines tech savy contact.
From there Boeing was then asked about the "finer details".
Murphy is an optimist
 
smartplane
Posts: 1024
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Re: Did the 737 MAX go one step too far?

Sun Dec 16, 2018 6:10 pm

AvObserver wrote:
[quote="kalvado]
In either case, I am taking the credit for making sure you at least read some professional opinions about the situation.
ANd I am talking about a different piece: https://leehamnews.com/2018/11/14/boein ... he-pilots/
Yes, that describes an instability in a certain corner of the flight envelope. Fundamental instability? I don't know if that is the appropriate term.
Yes, it takes some pilot's determination to even get to that corner, as pilots are explicitly trained NOT to get there, recognize the condition and back out into the greener pastures.. Any talk about "disabling MCAS and hand flying" is meaningless, MCAS is a last ditch effort to save the plane and make a difference between a reportable accident and an actual crash.
Boeing is correct in saying regular pilot would never know about MCAS (properly functional MCAS at least) and lack of MCAS training IMHO is not totally unreasonable (although likely illegal - but that is a different story). Properly is the keyword, though.
Now an issue of what happens in that corner of the flight envelope got a life of its own. It is not directly related to Lion crash - but it was brought into a spotlight by the crash; and it is an interesting part of this "too far" discussion. Of course, it is interesting as long as we keep it technical, and maybe legal - not fanboy or emotions.[/quote]
I would still like to hear Boeing's exact statement for the rationale behind the MCAS. One indisputable fact as I see it though is that the pilots should have known all there is to know about the MCAS and that Boeing and the FAA are seemingly complicit in ensuring its existence wasn't properly disclosed to them.[/quote][/quote]

If there was instability in a certain part of the flight envelope for the NG, one would have to conclude it was greater in the MAX. One would also have to conclude the instability in the MAX would differ between the smallest and largest model variants.

For the STC, what questions did the FAA ask in respect to MCAS, and what information was volunteered? A new name for a pre-existing system in the NG?

Grandfathering has a lot to answer for, because it encourages a culture of less than full and frank discussion. Document too many differences in respect to flight and maintenance, and place the STC at risk. The regulatory industry needs to create a new paradigm, where the cost of an STC is based on the age of the original Type Certificate, rising to the point where it's the same cost (or lower) to apply for a new Type Certificate.
 
WIederling
Posts: 8741
Joined: Sun Sep 13, 2015 2:15 pm

Re: Did the 737 MAX go one step too far?

Sun Dec 16, 2018 6:23 pm

When he cites that the engines have been placed ahead of the CG line (comparing the MAX to the NG) how does he know that Boeing didn't relocate some systems aft to compensate for this and rebalance the aircraft to a point at least?

Björn writes about CoD(drag) i.e. drag sources ( engine nacelles ) being further out and higher up relative the CoG.
Observations you can count off your fingers. no need to be handfed by Boeing.

Few seem to have read the article with cognition.
Murphy is an optimist
 
Ufsatp
Posts: 40
Joined: Wed May 24, 2017 6:21 pm

Re: Did the 737 MAX go one step too far?

Mon Dec 17, 2018 12:28 am

WIederling wrote:
Ufsatp wrote:
It kind of proves that Boeing did tell the airlines about it. If the other airlines didn’t feel the need to pass it along to their pilots...

Nothing says Boeing was the active part.

It could as well have been a surprise find by that airlines tech savy contact.
From there Boeing was then asked about the "finer details".



Nothing but your anti Boeing bias says they weren't the active one, either. We know it was in the United MAX differences bulletin. And since according to you upthread..... :rotfl:
WIederling wrote:
Ufsatp wrote:

Does Boeing train airline pilots or do the individual airlines train their own pilots?


Whatever. As the Manufacturer Boeing has to provide the basic curriculum.
 
crazyplane1234
Posts: 84
Joined: Wed Jan 13, 2016 6:58 am

Re: Did the 737 MAX go one step too far?

Mon Dec 17, 2018 6:36 am

Jouhou wrote:
Tiny lavatories aren't something people can escape by upgrading their seat. If an airline decides to inflict this upon their premium pax as well, that means people who won't take in consideration anything other than price are in fact inflicting their damage on everyone else.

Also airlines need to not do this. No. Unless you are some ultra bargain-bin airline, just please don't.

Point taken on the lavs, but you've yet to convince me on the seats.
 
User avatar
seahawk
Posts: 8622
Joined: Fri May 27, 2005 1:29 am

Re: Did the 737 MAX go one step too far?

Mon Dec 17, 2018 7:36 am

I think the debate needs to differentiate 4 different topics

1. basic plane design
2. basic flight characteristics
3. implementation of the MCAS
4. crew training on faults of the MCAS

A flight envelope protection system is a normal solution and used by many aircraft, the implementation, sensor usage and man to machine interface of the system, deserves a review though.
 
WIederling
Posts: 8741
Joined: Sun Sep 13, 2015 2:15 pm

Re: Did the 737 MAX go one step too far?

Mon Dec 17, 2018 8:20 am

Ufsatp wrote:
Nothing but your anti Boeing bias says they weren't the active one, either. We know it was in the United MAX differences bulletin. And since according to you upthread..... :rotfl:


I don't have a direct anti B bias. But I do have an anti deception and lying bias.

Afaics you mix the post crash B bulletin and the pre crash instructions for United pilots things.
( we actually don't know what those pilots got told.)

Then pilot curriculum is Boeing's job as I wrote before.
But afaics Boeing did not sufficiently fill this requirement.

So while :rotfl:ing on the floor be careful not to get your head stuck in the sand.
Murphy is an optimist
 
dakota123
Posts: 233
Joined: Wed Aug 30, 2006 11:03 pm

Re: Did the 737 MAX go one step too far?

Tue Dec 18, 2018 3:12 pm

WIederling wrote:
dakota123 wrote:
My opinion is that if the stability issue were as grave as the poster makes out, there is no way that there would be such a measured response.


The 787 battery issues culminated in a grounding only after a US plane was involved.
Afair the same applied to the MD10 and its design issues?


Apologies, by 'measured response', I meant controls response, per my original post on the topic. I don't disagree at all that Boeing has the appearance of being slow on the uptake.
“And If I claim to be a wise man, well surely it means that I don’t know”
 
catiii
Posts: 3122
Joined: Mon Mar 31, 2008 1:18 am

Re: Did the 737 MAX go one step too far?

Wed Dec 19, 2018 3:16 am

WayexTDI wrote:
Ufsatp wrote:
WIederling wrote:

Whatever. As the Manufacturer Boeing has to provide the basic curriculum.


It’s not whatever. Boeing has said they told the airlines about it. Look past your jealousy fueled hate of Boeing to see that.

“You may have seen media reports that we intentionally withheld information about airplane functionality from our customers. That’s simply untrue,” Muilenburg wrote. “The relevant function is described in the Flight Crew Operations Manual, and we routinely engage customers about how to operate our airplanes safely.”

It's funny how some on here say we have to trust the MAX pilots when they say the MAX is not an unstable aircraft; yet, the same MAX pilots cannot be trusted when they say they were not made aware of the functioning of the MCAS system...
Kinda double standard, ain't it?

FWIW, I trust the pilots in what they are saying: the MAX is not inherently unstable, but some groups of pilots were kept in the dark(ish?) about the MCAS.


Then those pilots need to engage their union and their flight ops leadership in a WTF moment, and ask why their curriculum did not include anything about the MCAS. It is in the FCOM, and one has to wonder about the AA and WN training departments, and why they aren't training on it then. UA knew enough to train on it.

Any other facts you want to change in this conversation?
 
catiii
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Re: Did the 737 MAX go one step too far?

Wed Dec 19, 2018 3:21 am

WayexTDI wrote:
B737900ER wrote:
WayexTDI wrote:

If the MCAS was so darn critical, don't you think Boeing should have highlighted it as such?
Not everything is critical to fly an aircraft; some things are (different speeds, different critical systems). MCAS appears to be one of them.

Who’s to say they didn’t highlight it to the operators. Boeing, Airbus, or however builds the planes don’t train airline pilots. Apparently only one operator thought it was critical enough to alert their pilots.

Don’t take it so personal. That’s how the industry works. The emotion on here over multinational corporations and machinery is mind blowing.

Absolutely. Your need to make sure to mention UA was trained is absolutely mind blowing.


At least he's repeating facts. You're not familiar with those. Remember when you were asserting that UA ALPA was saying they weren't trained, when in fact they were saying they were?

WayexTDI wrote:
catiii wrote:
fsabo wrote:

It is not the accident itself. It is the silent addition of MCAS because the MAX is _less_ stable than the NG.

From a commercial perspective boeing had to do the MAX. They had no other conceivable response to the NEO. They later found out that this adversely effected stability, so they threw in a kludge in the flight control and kept quiet about it. Is that a step too far? IMO, yes.


Silent addition? Couldn’t have been too silent. UA trained on the system...

UA ALPA seems to disagree: https://airlinerwatch.com/one-more-pilo ... -max-jets/ or https://www.chicagotribune.com/business ... story.html
 
Ufsatp
Posts: 40
Joined: Wed May 24, 2017 6:21 pm

Re: Did the 737 MAX go one step too far?

Wed Dec 19, 2018 12:29 pm

WIederling wrote:
Ufsatp wrote:
Nothing but your anti Boeing bias says they weren't the active one, either. We know it was in the United MAX differences bulletin. And since according to you upthread..... :rotfl:


I don't have a direct anti B bias. [/qoute]

Now that is funny...Talking about having your head in the sand.

WIederling wrote:

Afaics you mix the post crash B bulletin and the pre crash instructions for United pilots things.
( we actually don't know what those pilots got told.


I am not mixing anything. Read the article.

https://www.forbes.com/sites/tedreed/20 ... 8d8cbc7d5e
 
dtw2hyd
Posts: 7075
Joined: Wed Jan 09, 2013 12:11 pm

Re: Did the 737 MAX go one step too far?

Wed Dec 19, 2018 1:11 pm

Ufsatp wrote:
WayexTDI wrote:
B737900ER wrote:
Who’s to say they didn’t highlight it to the operators. Boeing, Airbus, or however builds the planes don’t train airline pilots. Apparently only one operator thought it was critical enough to alert their pilots.

Don’t take it so personal. That’s how the industry works. The emotion on here over multinational corporations and machinery is mind blowing.

Absolutely. Your need to make sure to mention UA was trained is absolutely mind blowing.


It kind of proves that Boeing did tell the airlines about it. If the other airlines didn’t feel the need to pass it along to their pilots...


All it implies is that Boeing may be treating and supporting customers differently based on contract clauses and liability exposure. No proof, just a wild guess, like yours.
 
WayexTDI
Posts: 1172
Joined: Fri Sep 21, 2018 4:38 pm

Re: Did the 737 MAX go one step too far?

Wed Dec 19, 2018 1:26 pm

catiii wrote:
WayexTDI wrote:
B737900ER wrote:
Who’s to say they didn’t highlight it to the operators. Boeing, Airbus, or however builds the planes don’t train airline pilots. Apparently only one operator thought it was critical enough to alert their pilots.

Don’t take it so personal. That’s how the industry works. The emotion on here over multinational corporations and machinery is mind blowing.

Absolutely. Your need to make sure to mention UA was trained is absolutely mind blowing.


At least he's repeating facts. You're not familiar with those. Remember when you were asserting that UA ALPA was saying they weren't trained, when in fact they were saying they were?

WayexTDI wrote:
catiii wrote:

Silent addition? Couldn’t have been too silent. UA trained on the system...

UA ALPA seems to disagree: https://airlinerwatch.com/one-more-pilo ... -max-jets/ or https://www.chicagotribune.com/business ... story.html

I wasn't asserting UA didn't know about the system, I was citing a communique from the same UA ALPA; basicall, the information wasn't POOMA, but backed up by actual documents.
They seem to have changed their mind, whereas AA & WN unions have not.

Again, it's been repeated here by me and others as well: Boeing appears to have not informed all airlines to the same extent and appears to have not made this (apparently) critical system a mandatory training point.
Care to keep running around the bush to absolve Boeing?
 
User avatar
767333ER
Posts: 967
Joined: Wed Jun 15, 2016 5:14 am

Re: Did the 737 MAX go one step too far?

Sun Dec 23, 2018 3:46 pm

FriscoHeavy wrote:
767333ER wrote:
The problem for me is how many times they have given the 737 a makeover, but how they had to cut so many corners (almost all not serious but frustrating) to keep the same type certificate. In that respect it has gone too far. I don’t care if it’s reliable, efficient, or a workhorse if the working conditions on that thing are worse to just about anything else built currently that even remotely competes with it or is agree than it. It obviously doesn’t work this way, but I were working on a 737 as a pilot,cabin crew, maintenance tech I’d feel like I should be getting paid more than doing an equal job on the A320 just because it’s so poorly set up in some respects that it makes the job a lot more complicated and/or fatiguing.


It's not at all unsafe, so it doesn't matter how many times they've refreshed it. It remains competitive and is safe. No serious corners have been cut.

Response not at all to the point. I’m not talking in a sense of safety where it potentially could be a less safe design, but besides the point. Those old 1960s doors are a DISASTER! I’ve noticed when the beginners doing the cabin trainers the tend to fail to open that stupid thing the first few times around. It’s basically 2019, stop being cheap and replace those manual girt bars and put doors that have slide rafts so that they don’t have to waste time setting up the life rafts in the cabin. The galley is a joke, just ask the AC FA’s that spent years working on the A320 and now work on the MAX sometimes. The cockpit is also a joke as the plane can’t really tell you what’s wrong with it and it can’t tell you when the MCAS is about to send you diving for the ocean and you can’t use the trick to stop it like you could stop STS on the older versions. Any pilot, or other airline employee I know personally says it does it’s job well, but it’s basically a piece of junk.
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