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kalvado
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 2:50 am

SEPilot wrote:
MrBretz wrote:
Not that we didn’t know this already, but here is a highly unfavorable article about Lion Air. I might be flying a MAX someday but never on Lion.

https://www.nytimes.com/2019/11/24/worl ... nesia.html

The fact that the first crash was Lion caused me and I suspect a lot of other people to doubt how much Boeing was really at fault. Had it been any other carrier I would have looked much harder at Boeing. It was only after the second crash that I was regally willing to look seriously at the possibility that Boeing had screwed up.

Apparently Boeing thought the same way, and they are paying the price for prejudice right now....
 
Fuling
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 3:17 am

Sorry if I've missed it, but what's the breakdown of stored MAX around the world by Boeing (pre-deliveries)? By carrier and location?
 
sgrow787
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 3:59 am

maint123 wrote:
Quite a long discussion on 2 planes which are essentially the same....as per Boeing and certified by FAA.
https://www.google.com/amp/s/qz.com/158 ... ining/amp/
A American pilot was uncomfortable flying the plane without extra training, so was deplaned and docked 3000 $ in pay.
Not lion air, a American airlines.


Well this certainly makes my point even more... mention of MCAS in the FCOM would have resulted in a lot more than 50 pilots wanting training, and some of those pilots would have raised a stink that MCAS could fire off a single AOA and fire repetitively. Does anyone know if any Brazilian pilots made a stink about anything - since their manuals did indeed have MCAS mentioned? Has that manual been released to the public?

On a sidenote, I'm hoping Ethiopian Airlines stores off one of their original 737 Maxes, with MCAS 1.0 installed, for reference purposes. Once MCAS 2.0 is loaded, the original evidence is gone.
Just one sensor,
Oh just one se-en-sor,
Just one sensor,
Ooh ooh oo-ooh
Oo-oo-ooh.
 
maint123
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 4:25 am

sgrow787 wrote:
maint123 wrote:
Quite a long discussion on 2 planes which are essentially the same....as per Boeing and certified by FAA.
https://www.google.com/amp/s/qz.com/158 ... ining/amp/
A American pilot was uncomfortable flying the plane without extra training, so was deplaned and docked 3000 $ in pay.
Not lion air, a American airlines.


Well this certainly makes my point even more... mention of MCAS in the FCOM would have resulted in a lot more than 50 pilots wanting training, and some of those pilots would have raised a stink that MCAS could fire off a single AOA and fire repetitively. Does anyone know if any Brazilian pilots made a stink about anything - since their manuals did indeed have MCAS mentioned? Has that manual been released to the public?

On a sidenote, I'm hoping Ethiopian Airlines stores off one of their original 737 Maxes, with MCAS 1.0 installed, for reference purposes. Once MCAS 2.0 is loaded, the original evidence is gone.

Not really. It would have been buried inside the manual and would have been ignored. And Boeing would have just said its all in the manual.
Companies all over the world bought Max because of Boeing's reputation. No one was ever going to guess how shoddily it has been engineered. See the confusion even on this site after a year of discussions. Some ppl still want to blame the pilots.
Even with hindsight and all the evidence, people are still circling the wagons.
Companies buy high technology products based on trust, since its cutting edge and very few actually understand it in depth.
Boeing has undone a lot of that trust with the MAX.
 
2175301
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 4:33 am

I would like to go back and discuss Jim Marko's concerns from Transport Canada. I was away from home for several days.

As I read it I believe I understand the dilemma: I believe what he is saying is essentially:
1) As presented- apparently MCAS V2 still leaves a logic hole.

2) Would it not be reasonable to grant other waivers in this case, and allow the 737Max without any MCAS?

3) He is afraid that political processes will lead to the approval of item 1 without other proper considerations.

None of us here are likely privy to some of the details behind what "12.1" actually is, or the other steps. But, I see the logic above in his email.

I do now know how the FAA or the other regulators will respond. I do know enough about the design and regulation of safety critical systems in nuclear power plants to know that none of the above 3 points are unique.

I would like to point out the following which I believe will become part of the discussion:

A) With the exception of the very simplest of systems all computer controlled systems have logic holes in them at some level. The question then becomes what is the probability and severity of that logic hole. A very much related example of this is that Airbus found a logic hole in their A320 family flight control software for the latest generation larger engines that there would be problems in certain "rare" areas of the designed flight envelope. Currently a number of Airbus aircraft are flying with reduced loading as a result.

My opinion is that given how badly Boeing messed up the FMEA on the orignal MCAS V1. I doubt very much that Boeing has missed this logic hole on MCAS V2; and I highly suspect that the Regulators have been involved in detailed reviews and questioning the safety assessment of this logic hole.

B) There are always other options; and in fact from an aircraft performance standpoint perhaps the simplist solution would be to waiver the issue and not have MCAS at all. But, commercial operations always are a factor. You have to look at the cost of such a waiver - and not just to the regulatory process the company must go through, but to Boeing and its customers (Federal Regulations do require cost considerations to be considered up front. MCAS may well have won out on this point alone - even if designed right up front). It is also my personal opinion that someone at Boeing would have considered the "Waiver" approach - and it was rejected then.

C: Unless there is a very large critical issue a lot of final decisions have some politics involved. I've even seen trading done: Company Says - we would like to do "this." Regulator says... hmmm... we could agree to that based on history and have some reluctance to consider it; at the same time we would like the plant to do "that" (and no technical relationship between the "this" and "that"). Then when the plant agrees that they could do "that" the regulator agrees in that case that they would approve "this."

It will be interesting to see what the final result will be. I don't actually personally see anything really unusual here.

A final item D): I have in fact seen many instances where someone was not satisfied with what the overwhelming majority of a review team has concluded - and then raises the issue for further review (why was this leaked). I have not often seen their concern supported in the end.

I also believe that Transport Canada, the FAA and EISA and Brazil are concerned with that the email got leaked. I suspect there are a lot of similar emails discussing various issues; and I doubt this is the only email between the agencies that have seriously questioned something. The process only really works when the emails stay "privileged" until the end (otherwise, people stop talking to each other). It appears that all the regulators have been working together... and resolving many such things which we never see discussed in public. It's my opinion as a Professional Engineer who has worked with regulatory compliance and approvals that this process does need to stay "privileged" until the end result is agreed upon. There are a lot of factors being considered. Leaking an email only makes things more messy.

Have a great day,
 
sgrow787
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 4:36 am

maint123 wrote:
sgrow787 wrote:
Well this certainly makes my point even more... mention of MCAS in the FCOM would have resulted in a lot more than 50 pilots wanting training, and some of those pilots would have raised a stink that MCAS could fire off a single AOA and fire repetitively.


Not really. It would have been buried inside the manual and would have been ignored. And Boeing would have just said its all in the manual.


All it takes is one pilot to raise a stink. And once that pilot figured out he wasn't going to be taken seriously, he might have gone public with his concerns. Perhaps the very pilot in the referenced QZ article.
Just one sensor,
Oh just one se-en-sor,
Just one sensor,
Ooh ooh oo-ooh
Oo-oo-ooh.
 
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aerolimani
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 5:39 am

maint123 wrote:
Quite a long discussion on 2 planes which are essentially the same....as per Boeing and certified by FAA.
https://www.google.com/amp/s/qz.com/158 ... ining/amp/
A American pilot was uncomfortable flying the plane without extra training, so was deplaned and docked 3000 $ in pay.
Not lion air, a American airlines.

That is, indeed, a disconcerting story. Not only docked pay, but a black mark, a "missed trip," on his company record.

The article is from April 2019. Yet, I don't recall it being mentioned before in these threads. There are some very interesting tidbits:

“After completing [the video training session], over the next couple of days I got to thinking that, you know, they said it wasn’t a different airplane, it was just the same airplane with some differences,” he said. “But I went back over my notes, and I went back in the iPad and reviewed some of the information and I realized it was actually, it was the same airframe, but it had different instrumentation, some of the things were in different places, it sat on the ground differently, and it was just a different airplane.”

It sat on the ground differently?

Separately, a NASA-run database of confidential safety reports from US pilots recorded complaints from at least two pilots who flew the Max who said that they experienced the plane’s nose pitching down when they were in autopilot, which they were able to stop by shutting off autopilot. However MCAS is not supposed to activate when pilots are in autopilot mode—only when they are in manual flight mode. Boeing said it could not comment on those reports.

It's not necessarily MCAS-related, but it is a strange thing to occur while AP is on.

And, from the comments, an interesting perspective:
As this story unfolds, it continues to be a textbook case of corporate deviance.

- Complacency with training/safety programs

- Following the rules instead of common sense

- Dismissing concerns of employees

- Compartmentalization of decisions with no transparency

- No one wanted planes to fall from the sky, but assured themselves “we’re following protocol”
 
oschkosch
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 6:39 am

Looks like 2019 is completely off the table!

http://www.kake.com/story/41363600/faa- ... or-737-max

According to the Wichita Business Journal, the head of the Federal Aviation Administration hinted at the Dubai Airshow this week that the Boeing Co.’s hope of clearing the 737 MAX by the end of the year might be overly optimistic. Reiterating that his agency is working around safety and not a timeline, FAA Administrator Steve Dickson, according to a report from Gulf News, told reporters at the show that it “remains to be seen” if the MAX flies again before January and that a “more conservative” timeline would be March 2020.

Boeing has also repeatedly said that its outlook has only been its best assumption and that the MAX’s return will ultimately be up to global regulators. Dickson’s projection that late in the first quarter would be a more conservative outlook is more in line with U.S. airlines that have already removed the MAX from their schedules until March.


https://www.barrons.com/articles/boeing ... 1574428511

Gulf News reported Wednesday the Federal Aviation Administration believes Boeing’s January timeline for MAX reintroduction to service might be aggressive. FAA Administrator Steve Dickson told reporters March is more conservative, according to the report.
:stirthepot: :airplane: "This airplane is designed by clowns, who in turn are supervised by monkeys" :airplane: :stirthepot:
 
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keesje
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 7:28 am

oschkosch wrote:
Looks like 2019 is completely off the table!

http://www.kake.com/story/41363600/faa- ... or-737-max

According to the Wichita Business Journal, the head of the Federal Aviation Administration hinted at the Dubai Airshow this week that the Boeing Co.’s hope of clearing the 737 MAX by the end of the year might be overly optimistic. Reiterating that his agency is working around safety and not a timeline, FAA Administrator Steve Dickson, according to a report from Gulf News, told reporters at the show that it “remains to be seen” if the MAX flies again before January and that a “more conservative” timeline would be March 2020.

Boeing has also repeatedly said that its outlook has only been its best assumption and that the MAX’s return will ultimately be up to global regulators. Dickson’s projection that late in the first quarter would be a more conservative outlook is more in line with U.S. airlines that have already removed the MAX from their schedules until March.


https://www.barrons.com/articles/boeing ... 1574428511

Gulf News reported Wednesday the Federal Aviation Administration believes Boeing’s January timeline for MAX reintroduction to service might be aggressive. FAA Administrator Steve Dickson told reporters March is more conservative, according to the report.


Investors will forget, it's already 2 weeks ago.

https://www.fool.com/investing/2019/11/ ... onday.aspx
"Never mistake motion for action." Ernest Hemingway
 
checklist350
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 7:35 am

aerolimani wrote:
maint123 wrote:
“After completing [the video training session], over the next couple of days I got to thinking that, you know, they said it wasn’t a different airplane, it was just the same airplane with some differences,” he said. “But I went back over my notes, and I went back in the iPad and reviewed some of the information and I realized it was actually, it was the same airframe, but it had different instrumentation, some of the things were in different places, it sat on the ground differently, and it was just a different airplane.”

It sat on the ground differently?



IIRC the front landing gear was lengthened to win some extra ground clearance for the engines, tilting the airplane. Alongside flattening of the engines and the raised mounting position Boeing definately went the extra mile to make the LEAP fit.
 
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PixelFlight
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 7:47 am

oschkosch wrote:
Looks like 2019 is completely off the table!

http://www.kake.com/story/41363600/faa- ... or-737-max

According to the Wichita Business Journal, the head of the Federal Aviation Administration hinted at the Dubai Airshow this week that the Boeing Co.’s hope of clearing the 737 MAX by the end of the year might be overly optimistic. Reiterating that his agency is working around safety and not a timeline, FAA Administrator Steve Dickson, according to a report from Gulf News, told reporters at the show that it “remains to be seen” if the MAX flies again before January and that a “more conservative” timeline would be March 2020.

Boeing has also repeatedly said that its outlook has only been its best assumption and that the MAX’s return will ultimately be up to global regulators. Dickson’s projection that late in the first quarter would be a more conservative outlook is more in line with U.S. airlines that have already removed the MAX from their schedules until March.


https://www.barrons.com/articles/boeing ... 1574428511

Gulf News reported Wednesday the Federal Aviation Administration believes Boeing’s January timeline for MAX reintroduction to service might be aggressive. FAA Administrator Steve Dickson told reporters March is more conservative, according to the report.

March 2020 should be when the ET302 final report will be released to the public. Not a favorable period for a return to service from the communication point of view.
: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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BoeingVista
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 8:10 am

oschkosch wrote:
Looks like 2019 is completely off the table!

http://www.kake.com/story/41363600/faa- ... or-737-max



At what point do Boeing give up and dig a large hole to bury the MAX project, 18 months? 2 years? Because the timeline is heading towards that. I maintain that even if MAX does get back into service it only stays that way until the next crash and then it will be grounded for good.

2175301 wrote:
B) There are always other options; and in fact from an aircraft performance standpoint perhaps the simplist solution would be to waiver the issue and not have MCAS at all. But, commercial operations always are a factor. You have to look at the cost of such a waiver - and not just to the regulatory process the company must go through, but to Boeing and its customers (Federal Regulations do require cost considerations to be considered up front. MCAS may well have won out on this point alone - even if designed right up front). It is also my personal opinion that someone at Boeing would have considered the "Waiver" approach - and it was rejected then.


Well

A) Any waiver really depends on what the unaugmented stall characteristics are and Boeing are still not keen to demonstrate this.

B) A waiver at this point, simply because it cannot meet accepted, legal certification & safety standards would creates a huge liability issue for all organizations in the chain, I very much doubt that EASA which is under far less political pressure will sign off on this.

Also any idea what CAT means in the context of the email?
BV
 
XRAYretired
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 8:22 am

BoeingVista wrote:
oschkosch wrote:
Looks like 2019 is completely off the table!

http://www.kake.com/story/41363600/faa- ... or-737-max



At what point do Boeing give up and dig a large hole to bury the MAX project, 18 months? 2 years? Because the timeline is heading towards that. I maintain that even if MAX does get back into service it only stays that way until the next crash and then it will be grounded for good.

2175301 wrote:
B) There are always other options; and in fact from an aircraft performance standpoint perhaps the simplist solution would be to waiver the issue and not have MCAS at all. But, commercial operations always are a factor. You have to look at the cost of such a waiver - and not just to the regulatory process the company must go through, but to Boeing and its customers (Federal Regulations do require cost considerations to be considered up front. MCAS may well have won out on this point alone - even if designed right up front). It is also my personal opinion that someone at Boeing would have considered the "Waiver" approach - and it was rejected then.


Well

A) Any waiver really depends on what the unaugmented stall characteristics are and Boeing are still not keen to demonstrate this.

B) A waiver at this point, simply because it cannot meet accepted, legal certification & safety standards would creates a huge liability issue for all organizations in the chain, I very much doubt that EASA which is under far less political pressure will sign off on this.

Also any idea what CAT means in the context of the email?

'CAT is shorthand for 'CATASTROPHIC'.

Ray
 
rheinwaldner
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 9:34 am

CriticalPoint wrote:
Noshow wrote:
How about auto deploying some flaps in case of a stall approaching? We're talking about slow flight aren't we?


This already exists on the 777 it’s called auto slats and on the 787 it’s called auto gap. It moves the slats to the full position but ONLY when the slats are in the mid position. So not when Flaps and Slats are up.

It’s been to long since Iv flown a 737 I can’t remember if they have this, but the technology is there.

Based on which sensors would the flaps be deployed? How many redundant sensors? Calculated by which computers? What if they disagree? The erroneous activation of that trigger would need to be avoided at all cost too.

beechnut wrote:
The Transport Canada memo seems to be saying that either way it goes (MCAS or no MCAS), the MAX won't meet certification standards, but by removing MCAS, it will not be meeting standards in a somewhat less dangerous manner.

The design of the MAX seems really to be broken. Think about it: abandoning regulatory requirements alltogether shall be safer than providing a solution to comply with them? Whats wrong with Boeing? Why are they not capable to provide a functioning solution to address the regulatory requirement?

aerolimani wrote:
As we all know, there exists no “MCAS OFF” switch on the MAX. So, in order to fly the plane normally, in all configurations, but without MCAS, the plane would require custom modification to its software to disable MCAS functions. I’d also be curious what method they would use to simulate a MCAS-caused runaway trim, on a real plane. It’s this kind of flying where the test pilots really earn their salt.

Take off today afternoon with any of the stored MAX and use the cut-off switch to demonstrate the "benign" MCAS-off behaviour. Boeing should have done that the first day, MCAS was ever mentioned. The lack of such evidence probably means, that there is no "benign" MCAS-off behaviour.

morrisond wrote:
Or is the NY Times now not a credible source?

How can people continue to ignore articles like these?

Because they are off topic in the MAX grounding thread. They describe a general problem. In general Lionair might have room for improvement. But in regards of the MAX crash, they crossed way with an airplane, which happened to become a death trap so much more frequent than all other aircraft, that all these weaknesses are only ground noise compared to the glaring deficiencies of the MAX.

At best such articles serve as parable about what happened at Boeing during the MAX development. Only the impact on statistics due to Boeings manglings are much more evident...

Look, it is no secret, that safety standards differ world wide. Focus is laid differently. There are some countrys, in which people could not afford aviation services at all, if the trade off between safety and cost would not tend to focus on cost a bit more than in other places. That's just how it is.

But in the end aviation safety is measured in crashes and deaths. And looking very soberly at Lionair and similar airlines, you have to admit that people don't die frequently onboard their aircraft. The safety stats of Lionair are e.g. quite close to the global average and certainly not a magnitude of order worse as you make it sound like. They are e.g. an NG power user and not a single person died on one of their NGs so far.

morrisond wrote:
Yes MCAS is a terrible design and the MAX should probably not fly it is unsafe unaugmented. But then neither should any other design that can't pass the same test. It leads me to question what other flaws in basic aerodynamic stability are being hidden by the regs on modern augmented designs.

That many aircraft have augmented control systems is not the issue. Prior the MAX the other aircraft proved that augmented aircraft work well and safe. The MAX simply had a broken augmentation system. Therefore the MAX does not throw a shadow on the other augmented aircraft, it only throws a shadow on Boeings capability to ever upgrade their old models again.
Many things are difficult, all things are possible!
 
morrisond
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 11:33 am

P1aneMad wrote:
What we should keep in our minds while Boeing's PR machine has fluff pieces who are trying to deflect blame from Boeing published on a range of "reputable" newspapers and magazines is captain Sully's open letter to the editor of one such publication who published one such fluff piece:



Letter to the Editor
Capt. “Sully” Sullenberger
New York Times Magazine
Published in print on October 13, 2019

In “What Really Brought Down the Boeing 737 MAX?” William Langewiesche draws the conclusion that the pilots are primarily to blame for the fatal crashes of Lion Air 610 and Ethiopian 302. In resurrecting this age-old aviation canard, Langewiesche minimizes the fatal design flaws and certification failures that precipitated those tragedies, and still pose a threat to the flying public. I have long stated, as he does note, that pilots must be capable of absolute mastery of the aircraft and the situation at all times, a concept pilots call airmanship. Inadequate pilot training and insufficient pilot experience are problems worldwide, but they do not excuse the fatally flawed design of the Maneuvering Characteristics Augmentation System (MCAS) that was a death trap.

As one of the few pilots who have lived to tell about being in the left seat of an airliner when things went horribly wrong, with seconds to react, I know a thing or two about overcoming an unimagined crisis. I am also one of the few who have flown a Boeing 737 MAX Level D full motion simulator, replicating both accident flights multiple times. I know firsthand the challenges the pilots on the doomed accident flights faced, and how wrong it is to blame them for not being able to compensate for such a pernicious and deadly design. These emergencies did not present as a classic runaway stabilizer problem, but initially as ambiguous unreliable airspeed and altitude situations, masking MCAS. The MCAS design should never have been approved, not by Boeing, and not by the Federal Aviation Administration (FAA).

The National Transportation Safety Board has found that Boeing made faulty assumptions both about the capability of the aircraft design to withstand damage or failure, and the level of human performance possible once the failures began to cascade. Where Boeing failed, the Federal Aviation Administration (FAA) should have stepped in to regulate but it failed to do so. Lessons from accidents are bought in blood and we must seek all the answers to prevent the next one. We need to fix all the flaws in the current system — corporate governance, regulatory oversight, aircraft maintenance, and yes, pilot training and experience. Only then can we ensure the safety of everyone who flies.

Capt. “Sully” Sullenberger
http://www.sullysullenberger.com/my-letter-to-the-editor-of-new-york-times-magazine/


People keep posting this however they are always ignoring the last two sentences.

"We need to fix all the flaws in the current system — corporate governance, regulatory oversight, aircraft maintenance, and yes, pilot training and experience. Only then can we ensure the safety of everyone who flies."

I would say Sully agrees with the more balanced posters in this discussion. Those who would like to see everything addressed and fixed. Versus just closing there eyes sticking their fingers in there ears and screaming "No-No-No - Boeing must burn - everything else in aviation is perfect and if only we could shut Boeing down we will never have a crash again"
 
phollingsworth
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 11:48 am

PixelFlight wrote:
checklist350 wrote:
PixelFlight wrote:
:checkmark:
Maybe there realize that the manual trim wheels are not safe enough for them... :crazy:


I still don't understand why there is no possibility to switch off just MCAS. The fact they need a modified plane seems to suggest this is still not possible with MCAS v2? Maybe this is because you aren't supposed to be able to turn off a safety feature?

Anyhow, I also don't understand why the manual trim can't be powered by a separate electric motor. And a fallback diesel generator for additional redundancy.

I agree that this is strange that the regulators don't require that the FCCs trim command can be disabled independently from the manual electrical trim. Should not be a so big modification, and look more in line with the MAX=NG Boeing goal.

The A350 use a stab trim system like you describes with 2 electrical motors, but the power source is either the electrical normal power (2 generators on each 2 engines + APU generator) or the emergency RAM air turbine generator, so 6 redundant power sources. There no manual trim wheels on the A350, just a stab trim backup switches. The irony is that the 737 classic did have two electrical motors, but not for redundancy, one was for the manual electric trim and the other for the FCCs AP.


Why Boeing went away for the two stage trim cutoff that the NGs had I am not clear on, it existed from the days of the two separate motors, but was carried through to the NGs. It allows a mush more graceful failover situation.

On redundancy, the A350s system is at most dual redundant, as that is the shallowest part of the chain. The power systems have a deeper depth, which may be sensible, but that doesn’t change the overall trim systems redundancy. On the 737 the trim redundancy is provided by dissimilar systems, the primary electric motor and the mk1 human. In principle having dissimilar systems is actually better as their failure modes are less likely to overlap. Note: the details of this are critical as an overstimulated crew member is probably the last thing you want as a the redundant system.
 
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scbriml
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 11:53 am

morrisond wrote:
Versus just closing there eyes sticking their fingers in there ears and screaming "No-No-No - Boeing must burn - everything else in aviation is perfect and if only we could shut Boeing down we will never have a crash again"


AFAICS, that's been said by precisely nobody. :shakehead:
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.
 
LondonAero
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 11:59 am

from the Transport Canada letter..."Not knowing the exact reasons for telling us that 12.1 as a fix is not effective (ref. F2.3 recent change to CAT), the fast is that it is another point that was just discovered."

Does anyone have any further color on this? Can the plane RTS without 12.1 as a fix? It looks like 12.1 was "the MCAS Authority Limit to ensure Pilot Control"....which I would take to mean reducing the amount the MCAS can move the nose down? I tend to think this goes back to the original issue of why BA increased the severity of the MCAS to begin with (and without telling anyone) - because it was necessary to offset the inherent instability? Thanks - any/all color appreciated.
 
morrisond
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 12:03 pm

scbriml wrote:
morrisond wrote:
Versus just closing there eyes sticking their fingers in there ears and screaming "No-No-No - Boeing must burn - everything else in aviation is perfect and if only we could shut Boeing down we will never have a crash again"


AFAICS, that's been said by precisely nobody. :shakehead:


Then you haven't been reading some of the posts by Rheinwaldner and others.
 
morrisond
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 12:05 pm

LondonAero wrote:
from the Transport Canada letter..."Not knowing the exact reasons for telling us that 12.1 as a fix is not effective (ref. F2.3 recent change to CAT), the fast is that it is another point that was just discovered."

Does anyone have any further color on this? Can the plane RTS without 12.1 as a fix? It looks like 12.1 was "the MCAS Authority Limit to ensure Pilot Control"....which I would take to mean reducing the amount the MCAS can move the nose down? I tend to think this goes back to the original issue of why BA increased the severity of the MCAS to begin with (and without telling anyone) - because it was necessary to offset the inherent instability? Thanks - any/all color appreciated.


It just didn't move fast enough to affect the control feel quick enough - MCAS trim rates are very similar to manual trim rates as initiated by the Pilots.
 
phollingsworth
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 12:15 pm

flipdewaf wrote:
morrisond wrote:
flipdewaf wrote:
That is pretty weird, it’s either needed or not right? I had heard that there was the potential to allow one MCAS application per high AoA event.


That’s totally illogical from a safety perspective though. If the solution to the handling issue is more dangerous than the handling characteristic that doesn’t mean we should accept the handling characteristic, it means you need a different solution.

If my solution so stop someone burning themselves on a hot pipe at work is to have a pit bull that rips your arm off of you get too close does not mean that we should remove the pit bull and just accept that people can burn themselves.



There are no magic bullets, there are reasonable improvements hat add to the safety of the system, FBW being one of them.


I wasn’t aware of the controls going light in turbulence. The reason why the control ‘feel’ is so important is because the human body is much better at force based proprioception than displacement proprioception.

Sorry Morrisond I feel I’m picking on you, I’m not, you just being up interesting points that I can look up and answer to on my phone.

Fred


Sent from my iPhone using Tapatalk


No worries at all.

The big question is does the MAX have handling issues that aren't that benign.
we know that the handling is not benign enough to pass the regulatory hurdles, if we can ignore this regulation because it’s difficult to pass then that’s a whole different can of worms being opened!

morrisond”]

If it does then the best solution is probably to put a bullet into it. [/quote]

I disagree, implementation of MCAS in a more robust way is ok.

[quote="morrisond wrote:
If not and the controls just get lighter than allowed (and reportedly it was only when the MAX was really light and loaded close to the AFT COG limit) it should not be materially less safe without MCAS.

My brain doesn’t appear to functioning today but as far as I can make out the phenomenon that MCAS is trying to rectify is that’s the engines produce a nonlinear shift of the centre of lift forward that the the normal shift of the centre lift rearwards due to the effect of the elevators. I can’t grok how the CoG alters this purely aerodynamic phenomenon.


....


Just about right. The engine-wing interaction shifts the aircraft neutral point forward at high AOA. The location of the centre of (pressure) will also shift. This is because the outboard wing unloads well before the inboard wing. The engines will contribute some to this. However, this effect is universal to all swept-wing aircraft with engines underneath and forward of the wing. The biggest change for the MAX is that the interference between the nacelle and the wing is greater than before. This exacerbates the issue.

By moving the neutral point closer to the cg this increases the effectiveness of the elevators. This means that any given increment input to the elevator produces are larger pitch input. This is “lightening”. The lightening will occur to some extend regardless of the cg location. It is possible that this shift could render the aircraft statically unstable, eg a small perturbation from trim would require nose down input. This will very much depend on cg location. You can do a first-order analysis to determine if this is true. Estimate the neutral point for the 737 at low AOA. Use the 1/4 MAC for the whole wing, fuselage, and tail. Then estimate the nacelles based on the aerodynamic centre being located at 1/4 of their “cord”. At high AoAs leave the tail, fuselage, and nacelles as is; however, assume the entire outboard wing is “lost”. This means you have two MACs, the inboard one still has a positive lift curve slope and the outboard one doesn’t. Estimate the new neutral point and see if the aft most cg position is near or behind this. Does the MAX have a significantly different cg envelope from the NG?
 
saab2000
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 12:24 pm

I fly 737s for a living and have about 100 hours in the MAX8. With the return to service being pushed back and back and back and so little firm information forthcoming, I’m actually beginning to ask if this airplane will ever see commercial service again.
smrtrthnu
 
AirBoat
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 12:31 pm

I notice on flightaware that on Saturday, Boeing was still doing what looks like stall testing on a 737max.
What could they be testing if everything was handed over?
As for testing with MCAS switched off. Just the switches wont do it, because mcas is still running in the background. It would take a menu in the flight computer software with an option of 'MCAS off'. This would probably take another 2 months to code up.
Does MCAS have any effect on the elevator?
 
flipdewaf
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 12:32 pm

phollingsworth wrote:
flipdewaf wrote:
morrisond wrote:

No worries at all.

The big question is does the MAX have handling issues that aren't that benign.
we know that the handling is not benign enough to pass the regulatory hurdles, if we can ignore this regulation because it’s difficult to pass then that’s a whole different can of worms being opened!

morrisond”]

If it does then the best solution is probably to put a bullet into it. [/quote]

I disagree, implementation of MCAS in a more robust way is ok.

[quote="morrisond wrote:
If not and the controls just get lighter than allowed (and reportedly it was only when the MAX was really light and loaded close to the AFT COG limit) it should not be materially less safe without MCAS.

My brain doesn’t appear to functioning today but as far as I can make out the phenomenon that MCAS is trying to rectify is that’s the engines produce a nonlinear shift of the centre of lift forward that the the normal shift of the centre lift rearwards due to the effect of the elevators. I can’t grok how the CoG alters this purely aerodynamic phenomenon.


....


Just about right. The engine-wing interaction shifts the aircraft neutral point forward at high AOA. The location of the centre of (pressure) will also shift. This is because the outboard wing unloads well before the inboard wing. The engines will contribute some to this. However, this effect is universal to all swept-wing aircraft with engines underneath and forward of the wing. The biggest change for the MAX is that the interference between the nacelle and the wing is greater than before. This exacerbates the issue.

By moving the neutral point closer to the cg this increases the effectiveness of the elevators. This means that any given increment input to the elevator produces are larger pitch input. This is “lightening”. The lightening will occur to some extend regardless of the cg location. It is possible that this shift could render the aircraft statically unstable, eg a small perturbation from trim would require nose down input. This will very much depend on cg location. You can do a first-order analysis to determine if this is true. Estimate the neutral point for the 737 at low AOA. Use the 1/4 MAC for the whole wing, fuselage, and tail. Then estimate the nacelles based on the aerodynamic centre being located at 1/4 of their “cord”. At high AoAs leave the tail, fuselage, and nacelles as is; however, assume the entire outboard wing is “lost”. This means you have two MACs, the inboard one still has a positive lift curve slope and the outboard one doesn’t. Estimate the new neutral point and see if the aft most cg position is near or behind this. Does the MAX have a significantly different cg envelope from the NG?


That makes sense, Does the engine and its position itself create the additional lift forward of the previous center of pressure at high AoA or is it that the New position of the engine unloads the outer portions of the wing in a different way due to modified flows?

Fred
Image
 
Noshow
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 12:35 pm

For testing purposes: Couldn't you just fool the MCAS computer by sending him some (faked) signal "autopilot is on" or "flaps are down" to let it stay inactive?
 
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PixelFlight
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 12:37 pm

morrisond wrote:
LondonAero wrote:
from the Transport Canada letter..."Not knowing the exact reasons for telling us that 12.1 as a fix is not effective (ref. F2.3 recent change to CAT), the fast is that it is another point that was just discovered."

Does anyone have any further color on this? Can the plane RTS without 12.1 as a fix? It looks like 12.1 was "the MCAS Authority Limit to ensure Pilot Control"....which I would take to mean reducing the amount the MCAS can move the nose down? I tend to think this goes back to the original issue of why BA increased the severity of the MCAS to begin with (and without telling anyone) - because it was necessary to offset the inherent instability? Thanks - any/all color appreciated.


It just didn't move fast enough to affect the control feel quick enough - MCAS trim rates are very similar to manual trim rates as initiated by the Pilots.

What prove did you have to support that the 12.1 CAT is caused by the MCAS trim rate ? Others speculative reasons can exists. The first is that this limitation could simply contradict the amount of trim required by MCAS to not be in catastrophic longitudinal characteristics at low speed. An other reason is that this limitation must involve speed measurement and will not work properly in case of speed disagree or any issue related to speed measurement. Yet another issue can be the reliability of the actual stab trim angle measurement, because the limitation could be a closed loop. Etc...
:stirthepot: 737-8 MAX: "For all speeds higher than 220 Kts and trim set at a value of 2.5 units, the difficulity level of turning the manual trim wheel was level A (trim wheel not movable)." :stirthepot:
 
morrisond
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 12:41 pm

PixelFlight wrote:
morrisond wrote:
LondonAero wrote:
from the Transport Canada letter..."Not knowing the exact reasons for telling us that 12.1 as a fix is not effective (ref. F2.3 recent change to CAT), the fast is that it is another point that was just discovered."

Does anyone have any further color on this? Can the plane RTS without 12.1 as a fix? It looks like 12.1 was "the MCAS Authority Limit to ensure Pilot Control"....which I would take to mean reducing the amount the MCAS can move the nose down? I tend to think this goes back to the original issue of why BA increased the severity of the MCAS to begin with (and without telling anyone) - because it was necessary to offset the inherent instability? Thanks - any/all color appreciated.


It just didn't move fast enough to affect the control feel quick enough - MCAS trim rates are very similar to manual trim rates as initiated by the Pilots.

What prove did you have to support that the 12.1 CAT is caused by the MCAS trim rate ? Others speculative reasons can exists. The first is that this limitation could simply contradict the amount of trim required by MCAS to not be in catastrophic longitudinal characteristics at low speed. An other reason is that this limitation must involve speed measurement and will not work properly in case of speed disagree or any issue related to speed measurement. Yet another issue can be the reliability of the actual stab trim angle measurement, because the limitation could be a closed loop. Etc...


The change was in Trim rate - in degrees per second - the poster called it severity - I just pointed out that it is not materially faster than existing Electric Trim rates.

Yes it could have been for other reasons - but the rate wasn't 2-3x normal.
 
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PixelFlight
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 12:43 pm

AirBoat wrote:
Does MCAS have any effect on the elevator?

No directly: MCAS only trim the horizontal stabilizer according to a lot of documents from many sources.
But as the elevator is part of the horizontal stabilizer, MCAS have obviously a big indirect effect on it.
:stirthepot: 737-8 MAX: "For all speeds higher than 220 Kts and trim set at a value of 2.5 units, the difficulity level of turning the manual trim wheel was level A (trim wheel not movable)." :stirthepot:
 
morrisond
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 12:44 pm

rheinwaldner wrote:
[ In general Lionair might have room for improvement.


Lionair "might" have room for improvement? That is like saying Boeing might have some issues in its certification process.
 
maint123
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 12:58 pm

morrisond wrote:
P1aneMad wrote:
What we should keep in our minds while Boeing's PR machine has fluff pieces who are trying to deflect blame from Boeing published on a range of "reputable" newspapers and magazines is captain Sully's open letter to the editor of one such publication who published one such fluff piece:



Letter to the Editor
Capt. “Sully” Sullenberger
New York Times Magazine
Published in print on October 13, 2019

In “What Really Brought Down the Boeing 737 MAX?” William Langewiesche draws the conclusion that the pilots are primarily to blame for the fatal crashes of Lion Air 610 and Ethiopian 302. In resurrecting this age-old aviation canard, Langewiesche minimizes the fatal design flaws and certification failures that precipitated those tragedies, and still pose a threat to the flying public. I have long stated, as he does note, that pilots must be capable of absolute mastery of the aircraft and the situation at all times, a concept pilots call airmanship. Inadequate pilot training and insufficient pilot experience are problems worldwide, but they do not excuse the fatally flawed design of the Maneuvering Characteristics Augmentation System (MCAS) that was a death trap.

As one of the few pilots who have lived to tell about being in the left seat of an airliner when things went horribly wrong, with seconds to react, I know a thing or two about overcoming an unimagined crisis. I am also one of the few who have flown a Boeing 737 MAX Level D full motion simulator, replicating both accident flights multiple times. I know firsthand the challenges the pilots on the doomed accident flights faced, and how wrong it is to blame them for not being able to compensate for such a pernicious and deadly design. These emergencies did not present as a classic runaway stabilizer problem, but initially as ambiguous unreliable airspeed and altitude situations, masking MCAS. The MCAS design should never have been approved, not by Boeing, and not by the Federal Aviation Administration (FAA).

The National Transportation Safety Board has found that Boeing made faulty assumptions both about the capability of the aircraft design to withstand damage or failure, and the level of human performance possible once the failures began to cascade. Where Boeing failed, the Federal Aviation Administration (FAA) should have stepped in to regulate but it failed to do so. Lessons from accidents are bought in blood and we must seek all the answers to prevent the next one. We need to fix all the flaws in the current system — corporate governance, regulatory oversight, aircraft maintenance, and yes, pilot training and experience. Only then can we ensure the safety of everyone who flies.

Capt. “Sully” Sullenberger
http://www.sullysullenberger.com/my-letter-to-the-editor-of-new-york-times-magazine/


People keep posting this however they are always ignoring the last two sentences.

"We need to fix all the flaws in the current system — corporate governance, regulatory oversight, aircraft maintenance, and yes, pilot training and experience. Only then can we ensure the safety of everyone who flies."

I would say Sully agrees with the more balanced posters in this discussion. Those who would like to see everything addressed and fixed. Versus just closing there eyes sticking their fingers in there ears and screaming "No-No-No - Boeing must burn - everything else in aviation is perfect and if only we could shut Boeing down we will never have a crash again"

Morrisond if you don't mind my asking are you a engineer with hands on experience in any industry?
I am from a non aviation industry but in my experience you can't play with the laws of physics for long. They always win.
When hundreds of Max re enter service, if the plane still has serious issues, large probability of another accident.
People are going to again wonder why pilots with 6000 hours of flying and maintenance teams don't have a issue with NG or neo, but can't control a Max.
The Neo has had more than 100 PW engine failures in less than a year and half but the plane still managed to land safely with a single engine in all these cases. Dont remember even one emergency declared. Because the inbuilt safety is in a broad band and not in a narrow band.
Boeing is not going to close but no one wants to see another crash.
 
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PixelFlight
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 1:07 pm

morrisond wrote:
It just didn't move fast enough to affect the control feel quick enough - MCAS trim rates are very similar to manual trim rates as initiated by the Pilots.
[...]
The change was in Trim rate - in degrees per second - the poster called it severity - I just pointed out that it is not materially faster than existing Electric Trim rates.

The change was not only the trim rate, the G force sensors was removed from the algorithm (at least a low speed) and the MCAS schedule table in function of AoA and speed was changed.
And keep in mind that the two crashes did not occurred at low speed (far from that) for which the trim rate was increased. This strongly indicate that the MCAS table was modified to use increased trim rate for higher speeds as well. This all look like there is something fishy about the 737-8/9 MAX longitudinal characteristics. The MCAS schedule table could be too scary to read outside Boeing...
: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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par13del
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 1:27 pm

rheinwaldner wrote:
Take off today afternoon with any of the stored MAX and use the cut-off switch to demonstrate the "benign" MCAS-off behaviour. Boeing should have done that the first day, MCAS was ever mentioned. The lack of such evidence probably means, that there is no "benign" MCAS-off behaviour.

You do know that when you do that you also disable the electric trim right?
Methinks that the regulators already know how the a/c flies like that, what they are looking for is the removal of MCAS while the electric trim remains active, as far as we know, there is no such option in a basic MAX, hence the need for a modification.

The conspiracy theorist could say that the regulators are setting a trap for Boeing, if they modify a MAX to remove MCAS, the regulators could then say that Boeing has demonstrated the a/c can be flown without MCAS then demand the certification of the a/c without MCAS which would take 1 to 2 years, thus rendering the a/c dead.
 
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par13del
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 1:32 pm

flipdewaf wrote:
That makes sense, Does the engine and its position itself create the additional lift forward of the previous center of pressure at high AoA or is it that the New position of the engine unloads the outer portions of the wing in a different way due to modified flows?

Fred

Ok, getting confused here, I thought that was understood and identified during MAX initial testing, they tried various hardware adjustments (I think the articles said vanes ) which were not effective enough to comply with the regulations so they ended up with MCAS.
 
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par13del
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 1:36 pm

maint123 wrote:
The Neo has had more than 100 PW engine failures in less than a year and half but the plane still managed to land safely with a single engine in all these cases. Dont remember even one emergency declared. Because the inbuilt safety is in a broad band and not in a narrow band.
Boeing is not going to close but no one wants to see another crash.

So the takeaway here is that the NEO is a safe a/c or the regulators are continuing to allow a faulty engine to continue flying because of the safety features of the a/c?
Did the regulators get gun shy after the 787 RR engine issue, or a widebody a/c easier to ground?
 
XRAYretired
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 1:45 pm

Review of Marko TCCA leaked email and presentation material.

Having had a little time to mull over what we have seen, there are a number of interesting takeaways and questions arising.

Firstly, I suggest that any notion of 'disgruntled employee' should be rejected. Mr Marko has communicated with his peers in comparative organisations in a clear way and has expressed his fears and proposed alternatives constructively.

It would seem to be clear that Mr Marko is somewhat isolated from the 'coalface', in that he has been advised of re-categorisation of a 12.1 related condition as CATASTROPHIC without the detail of why so. (Note: I would assume therefore, this is a finding of Boeing/FAA advised during routine update). It is also likely that Mr Marko has little, if any, more knowledge or understanding of the actual flight characteristics, and particularly those in relation to the regulation non-compliances, than the posters to this site have, or indeed that JATR had such that they could make no determination of the actual intention of MCAS.

Your analysts expressing despair may normally be a sign that you need to do a re-think (or they need a vacation!). The best hope is that Mr Marko's evident despair is at least partially related to isolation and not knowing what is actually going on.

Takeaways and questions arising.

It would seem, that the requirements/design may have become a 'rats nest'. I would draw this from continuing problems with architecture, ISSA issues and Mr Marko's thoughts to get rid of MCAS, and I would assume, FCC X Channel? It may be that the architecture/ISSA issues are directly or indirectly related to the software audit findings and suspension?

MCAS is directly connected to STALL ID on the charts. Ignoring misinterpretation or error, this implies that Mr Marko thinks MCAS is part of the Stall identification/prevention/protection scheme.

MCAS categorisation has recently been raised back to CATASTROPHIC and this is relation to MCAS authority limitation or, in other words, elevator authority maintenance being - ineffective-. My guess is that this must be related to either a flight corner condition where 2.5deg nose down can not be reliably recovered in a timely fashion or some other condition whereby elevator authority is further eroded or not sufficient before MCAS activation?

Software 12.1.1 includes and item' SW Column Cut-out'. This is new to me. Is it some sort of mitigation for inhibiting the hardware aft column cut-out? If so what does it actually do?

As some have questioned in these threads, Speed Trim induced STAB TRIM RUNAWAY (in fault condition) has been categorised as CATASTROPHIC. We can probably assume it was MINOR/MAJOR originally when subject to the dodgy PHA mitigation/discounts. This appears to have been addressed by procedural changes (and training likely, and we know that RUNAWAY STAB NNC was added to the training syllabus ~Feb 2019) but is not clear what 'Electric Trim', 'Control Speed' and 'Inhibit Stick Shaker' (note: Software 11.1 included a limitation of 5 minutes on single sided stick shaker) actually mean. There is also a box 'Boeing Post RTS Proposal'. Perhaps this indicates that there are further changes to Speed Trim in the pipeline?

I still don't expect that waiver of the non-compliances would be acceptable and I'm sure Boeing/FAA have considered it. Similarly, I would have thought that reliable compliance with Longitudinal Stability without augmentation has been ruled out. Even so, that leaves Mr Marko with 'NG FCC Adjustment'? This must be revision to STS/STALL ID that is not the addition of MCAS but something else? maybe the extension of STALL ID from Autopilot only to Manual as well. Potentially that puts us back to square one? (Note: I suspect that STALL ID activation may be responsible for reported cases of nose down trim during Autopilot Climb).

It would be interesting to know what the 'Common Mode' problem actually is and is it related to any of the other problems. Either way it will need to be addressed.

Whatever way this pans out, it would seem unlikely that the last notional schedule to RTS is out of the window since more change is required pushing back the serial items. Indeed, we would have expected Software audit, Pilot group simulator activity and FAA Cert. flight test to be completed by now-ish and there is no sign of that at the moment.

My views. Hope it helps to rationalise things. I Don't claim to be infallible or all-knowing.

Ray
 
LondonAero
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 2:00 pm

"Whatever way this pans out, it would seem unlikely that the last notional schedule to RTS is out of the window since more change is required pushing back the serial items. Indeed, we would have expected Software audit, Pilot group simulator activity and FAA Cert. flight test to be completed by now-ish and there is no sign of that at the moment".

Ray - do you think it is the software audit where these items have come up??
 
morrisond
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 2:03 pm

maint123 wrote:
morrisond wrote:
P1aneMad wrote:
What we should keep in our minds while Boeing's PR machine has fluff pieces who are trying to deflect blame from Boeing published on a range of "reputable" newspapers and magazines is captain Sully's open letter to the editor of one such publication who published one such fluff piece:



Letter to the Editor
Capt. “Sully” Sullenberger
New York Times Magazine
Published in print on October 13, 2019

In “What Really Brought Down the Boeing 737 MAX?” William Langewiesche draws the conclusion that the pilots are primarily to blame for the fatal crashes of Lion Air 610 and Ethiopian 302. In resurrecting this age-old aviation canard, Langewiesche minimizes the fatal design flaws and certification failures that precipitated those tragedies, and still pose a threat to the flying public. I have long stated, as he does note, that pilots must be capable of absolute mastery of the aircraft and the situation at all times, a concept pilots call airmanship. Inadequate pilot training and insufficient pilot experience are problems worldwide, but they do not excuse the fatally flawed design of the Maneuvering Characteristics Augmentation System (MCAS) that was a death trap.

As one of the few pilots who have lived to tell about being in the left seat of an airliner when things went horribly wrong, with seconds to react, I know a thing or two about overcoming an unimagined crisis. I am also one of the few who have flown a Boeing 737 MAX Level D full motion simulator, replicating both accident flights multiple times. I know firsthand the challenges the pilots on the doomed accident flights faced, and how wrong it is to blame them for not being able to compensate for such a pernicious and deadly design. These emergencies did not present as a classic runaway stabilizer problem, but initially as ambiguous unreliable airspeed and altitude situations, masking MCAS. The MCAS design should never have been approved, not by Boeing, and not by the Federal Aviation Administration (FAA).

The National Transportation Safety Board has found that Boeing made faulty assumptions both about the capability of the aircraft design to withstand damage or failure, and the level of human performance possible once the failures began to cascade. Where Boeing failed, the Federal Aviation Administration (FAA) should have stepped in to regulate but it failed to do so. Lessons from accidents are bought in blood and we must seek all the answers to prevent the next one. We need to fix all the flaws in the current system — corporate governance, regulatory oversight, aircraft maintenance, and yes, pilot training and experience. Only then can we ensure the safety of everyone who flies.

Capt. “Sully” Sullenberger
http://www.sullysullenberger.com/my-letter-to-the-editor-of-new-york-times-magazine/


People keep posting this however they are always ignoring the last two sentences.

"We need to fix all the flaws in the current system — corporate governance, regulatory oversight, aircraft maintenance, and yes, pilot training and experience. Only then can we ensure the safety of everyone who flies."

I would say Sully agrees with the more balanced posters in this discussion. Those who would like to see everything addressed and fixed. Versus just closing there eyes sticking their fingers in there ears and screaming "No-No-No - Boeing must burn - everything else in aviation is perfect and if only we could shut Boeing down we will never have a crash again"

Morrisond if you don't mind my asking are you a engineer with hands on experience in any industry?
I am from a non aviation industry but in my experience you can't play with the laws of physics for long. They always win.
When hundreds of Max re enter service, if the plane still has serious issues, large probability of another accident.
People are going to again wonder why pilots with 6000 hours of flying and maintenance teams don't have a issue with NG or neo, but can't control a Max.
The Neo has had more than 100 PW engine failures in less than a year and half but the plane still managed to land safely with a single engine in all these cases. Dont remember even one emergency declared. Because the inbuilt safety is in a broad band and not in a narrow band.
Boeing is not going to close but no one wants to see another crash.


No - I am not an engineer - just a Private citizen with Minimal (115 hours) of flying experience - not much less than those put into a cockpit of a 737/A320 these days.

So in whatever Industry you are - say Nuclear - and there was a design issue with the plant causing an accident but during the investigation it was determined that faulty parts were installed and the Operators had made errors.

Option A - Fix the design issue and ignore everything else.

Option B - Fix the design issue, the maintenance issues and the training issues

Are you suggesting Option A is the right answer? What happens if another design issue pops up or a critical safety part fails due to manufacturing or installation issues? Cross your fingers and hope for the best?
 
Nils75cz
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 2:05 pm

I keep on reading this thread but I'm about to give up. It is supposed to be about the 737 MAX grounding but it mostly revolves around the pilot skill theme, about the training theme... There will be a First Time for every single pilot out there. I would like to draw your attention to the fact that the thread is about the grounding of this specific aircraft model.

Lion Air didn't get grounded. Nor did Ethiopian. No Third World pilots got grounded.

The particular aircraft did, and I suppose there is a reason for that.

I respectfully appeal to all mods to keep this thread spam free.
 
rheinwaldner
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 2:18 pm

morrisond wrote:
Are you suggesting Option A is the right answer? What happens if another design issue pops up or a critical safety part fails due to manufacturing or installation issues? Cross your fingers and hope for the best?

Simple, design issues on this scales have not popped up for half a century and they should and will never pop up again.

The vendors have to ensure that. As I said earlier: pilots are not there to handle unfinished, dangerous and broken aircraft designs. They are there to handle their own failures as good as possible, supported by machines, which fail as rare and graceful as possible. A fault tolerance aircraft is the goal. Like any other plane out there. The MAX on the other hand was fault provoking. The exact opposite.
Many things are difficult, all things are possible!
 
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seahawk
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 2:20 pm

par13del wrote:
rheinwaldner wrote:
Take off today afternoon with any of the stored MAX and use the cut-off switch to demonstrate the "benign" MCAS-off behaviour. Boeing should have done that the first day, MCAS was ever mentioned. The lack of such evidence probably means, that there is no "benign" MCAS-off behaviour.

You do know that when you do that you also disable the electric trim right?
Methinks that the regulators already know how the a/c flies like that, what they are looking for is the removal of MCAS while the electric trim remains active, as far as we know, there is no such option in a basic MAX, hence the need for a modification.

The conspiracy theorist could say that the regulators are setting a trap for Boeing, if they modify a MAX to remove MCAS, the regulators could then say that Boeing has demonstrated the a/c can be flown without MCAS then demand the certification of the a/c without MCAS which would take 1 to 2 years, thus rendering the a/c dead.


I expected changes to the switchology in a previous debate and imho it makes a lot of sense, if you consider the limited effects of the trim wheel and the need to disable MCAS only.
 
phollingsworth
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 2:22 pm

flipdewaf wrote:
phollingsworth wrote:
flipdewaf wrote:
we know that the handling is not benign enough to pass the regulatory hurdles, if we can ignore this regulation because it’s difficult to pass then that’s a whole different can of worms being opened!

morrisond”]

If it does then the best solution is probably to put a bullet into it. [/quote]

I disagree, implementation of MCAS in a more robust way is ok.

[quote="morrisond wrote:
If not and the controls just get lighter than allowed (and reportedly it was only when the MAX was really light and loaded close to the AFT COG limit) it should not be materially less safe without MCAS.

My brain doesn’t appear to functioning today but as far as I can make out the phenomenon that MCAS is trying to rectify is that’s the engines produce a nonlinear shift of the centre of lift forward that the the normal shift of the centre lift rearwards due to the effect of the elevators. I can’t grok how the CoG alters this purely aerodynamic phenomenon.


....


Just about right. The engine-wing interaction shifts the aircraft neutral point forward at high AOA. The location of the centre of (pressure) will also shift. This is because the outboard wing unloads well before the inboard wing. The engines will contribute some to this. However, this effect is universal to all swept-wing aircraft with engines underneath and forward of the wing. The biggest change for the MAX is that the interference between the nacelle and the wing is greater than before. This exacerbates the issue.

By moving the neutral point closer to the cg this increases the effectiveness of the elevators. This means that any given increment input to the elevator produces are larger pitch input. This is “lightening”. The lightening will occur to some extend regardless of the cg location. It is possible that this shift could render the aircraft statically unstable, eg a small perturbation from trim would require nose down input. This will very much depend on cg location. You can do a first-order analysis to determine if this is true. Estimate the neutral point for the 737 at low AOA. Use the 1/4 MAC for the whole wing, fuselage, and tail. Then estimate the nacelles based on the aerodynamic centre being located at 1/4 of their “cord”. At high AoAs leave the tail, fuselage, and nacelles as is; however, assume the entire outboard wing is “lost”. This means you have two MACs, the inboard one still has a positive lift curve slope and the outboard one doesn’t. Estimate the new neutral point and see if the aft most cg position is near or behind this. Does the MAX have a significantly different cg envelope from the NG?


That makes sense, Does the engine and its position itself create the additional lift forward of the previous center of pressure at high AoA or is it that the New position of the engine unloads the outer portions of the wing in a different way due to modified flows?

Fred


Outboard wing unloads at high AOA, no different now then before. This is a function of sweep. The 757, 767 solution on this was vortex generators. The A300, A310 used stab trim in some instances. The engine placement leads to higher energy flow over the inboard wing, delaying separation and the reduction in the lift curve slope. This shifts the effective aerodynamic centre (be carful with centre of pressure as this moves constantly, at zero lift the centre of pressure for the wing is infinitely far aft). If it was just engine lift then this wouldn’t be a high AOA only issue, it would be present all the time.
 
XRAYretired
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 2:46 pm

LondonAero wrote:
"Whatever way this pans out, it would seem unlikely that the last notional schedule to RTS is out of the window since more change is required pushing back the serial items. Indeed, we would have expected Software audit, Pilot group simulator activity and FAA Cert. flight test to be completed by now-ish and there is no sign of that at the moment".

Ray - do you think it is the software audit where these items have come up??

I guess its posible. There would be other reviews and testing taking place in the same timeframe I expect.

Ray
 
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PixelFlight
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 3:23 pm

morrisond wrote:
maint123 wrote:
morrisond wrote:

People keep posting this however they are always ignoring the last two sentences.

"We need to fix all the flaws in the current system — corporate governance, regulatory oversight, aircraft maintenance, and yes, pilot training and experience. Only then can we ensure the safety of everyone who flies."

I would say Sully agrees with the more balanced posters in this discussion. Those who would like to see everything addressed and fixed. Versus just closing there eyes sticking their fingers in there ears and screaming "No-No-No - Boeing must burn - everything else in aviation is perfect and if only we could shut Boeing down we will never have a crash again"

Morrisond if you don't mind my asking are you a engineer with hands on experience in any industry?
I am from a non aviation industry but in my experience you can't play with the laws of physics for long. They always win.
When hundreds of Max re enter service, if the plane still has serious issues, large probability of another accident.
People are going to again wonder why pilots with 6000 hours of flying and maintenance teams don't have a issue with NG or neo, but can't control a Max.
The Neo has had more than 100 PW engine failures in less than a year and half but the plane still managed to land safely with a single engine in all these cases. Dont remember even one emergency declared. Because the inbuilt safety is in a broad band and not in a narrow band.
Boeing is not going to close but no one wants to see another crash.


No - I am not an engineer - just a Private citizen with Minimal (115 hours) of flying experience - not much less than those put into a cockpit of a 737/A320 these days.

So in whatever Industry you are - say Nuclear - and there was a design issue with the plant causing an accident but during the investigation it was determined that faulty parts were installed and the Operators had made errors.

Option A - Fix the design issue and ignore everything else.

Option B - Fix the design issue, the maintenance issues and the training issues

Are you suggesting Option A is the right answer? What happens if another design issue pops up or a critical safety part fails due to manufacturing or installation issues? Cross your fingers and hope for the best?

You are probably alone at thinking that others than you want option A. Discussing of others unrelated subjects into others threads is not a disagreement as you seem to imply so often. The world is not bound to this single thread about the 737-8/9 MAX grounding... It's not the fault of the contributors here that the civil aircraft industry don't actually take spectacular action to address those unrelated issues.
: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:
 
DenverTed
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 3:25 pm

phollingsworth wrote:
flipdewaf wrote:
morrisond wrote:

No worries at all.

The big question is does the MAX have handling issues that aren't that benign.
we know that the handling is not benign enough to pass the regulatory hurdles, if we can ignore this regulation because it’s difficult to pass then that’s a whole different can of worms being opened!

morrisond”]

If it does then the best solution is probably to put a bullet into it. [/quote]

I disagree, implementation of MCAS in a more robust way is ok.

[quote="morrisond wrote:
If not and the controls just get lighter than allowed (and reportedly it was only when the MAX was really light and loaded close to the AFT COG limit) it should not be materially less safe without MCAS.

My brain doesn’t appear to functioning today but as far as I can make out the phenomenon that MCAS is trying to rectify is that’s the engines produce a nonlinear shift of the centre of lift forward that the the normal shift of the centre lift rearwards due to the effect of the elevators. I can’t grok how the CoG alters this purely aerodynamic phenomenon.


....


Just about right. The engine-wing interaction shifts the aircraft neutral point forward at high AOA. The location of the centre of (pressure) will also shift. This is because the outboard wing unloads well before the inboard wing. The engines will contribute some to this. However, this effect is universal to all swept-wing aircraft with engines underneath and forward of the wing. The biggest change for the MAX is that the interference between the nacelle and the wing is greater than before. This exacerbates the issue.

By moving the neutral point closer to the cg this increases the effectiveness of the elevators. This means that any given increment input to the elevator produces are larger pitch input. This is “lightening”. The lightening will occur to some extend regardless of the cg location. It is possible that this shift could render the aircraft statically unstable, eg a small perturbation from trim would require nose down input. This will very much depend on cg location. You can do a first-order analysis to determine if this is true. Estimate the neutral point for the 737 at low AOA. Use the 1/4 MAC for the whole wing, fuselage, and tail. Then estimate the nacelles based on the aerodynamic centre being located at 1/4 of their “cord”. At high AoAs leave the tail, fuselage, and nacelles as is; however, assume the entire outboard wing is “lost”. This means you have two MACs, the inboard one still has a positive lift curve slope and the outboard one doesn’t. Estimate the new neutral point and see if the aft most cg position is near or behind this. Does the MAX have a significantly different cg envelope from the NG?

How come the outer wing unloads at approach to stall? I had always heard that the inner wing stalls first, because there is a twist and the inner wing is set relatively at a higher AOA than the outer wing.
Last edited by DenverTed on Mon Nov 25, 2019 3:38 pm, edited 1 time in total.
 
flipdewaf
Posts: 3566
Joined: Thu Jul 20, 2006 6:28 am

Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 3:28 pm

phollingsworth wrote:
flipdewaf wrote:
phollingsworth wrote:
My brain doesn’t appear to functioning today but as far as I can make out the phenomenon that MCAS is trying to rectify is that’s the engines produce a nonlinear shift of the centre of lift forward that the the normal shift of the centre lift rearwards due to the effect of the elevators. I can’t grok how the CoG alters this purely aerodynamic phenomenon.


....


Just about right. The engine-wing interaction shifts the aircraft neutral point forward at high AOA. The location of the centre of (pressure) will also shift. This is because the outboard wing unloads well before the inboard wing. The engines will contribute some to this. However, this effect is universal to all swept-wing aircraft with engines underneath and forward of the wing. The biggest change for the MAX is that the interference between the nacelle and the wing is greater than before. This exacerbates the issue.

By moving the neutral point closer to the cg this increases the effectiveness of the elevators. This means that any given increment input to the elevator produces are larger pitch input. This is “lightening”. The lightening will occur to some extend regardless of the cg location. It is possible that this shift could render the aircraft statically unstable, eg a small perturbation from trim would require nose down input. This will very much depend on cg location. You can do a first-order analysis to determine if this is true. Estimate the neutral point for the 737 at low AOA. Use the 1/4 MAC for the whole wing, fuselage, and tail. Then estimate the nacelles based on the aerodynamic centre being located at 1/4 of their “cord”. At high AoAs leave the tail, fuselage, and nacelles as is; however, assume the entire outboard wing is “lost”. This means you have two MACs, the inboard one still has a positive lift curve slope and the outboard one doesn’t. Estimate the new neutral point and see if the aft most cg position is near or behind this. Does the MAX have a significantly different cg envelope from the NG?


That makes sense, Does the engine and its position itself create the additional lift forward of the previous center of pressure at high AoA or is it that the New position of the engine unloads the outer portions of the wing in a different way due to modified flows?

Fred


Outboard wing unloads at high AOA, no different now then before. This is a function of sweep. The 757, 767 solution on this was vortex generators. The A300, A310 used stab trim in some instances. The engine placement leads to higher energy flow over the inboard wing, delaying separation and the reduction in the lift curve slope. This shifts the effective aerodynamic centre (be carful with centre of pressure as this moves constantly, at zero lift the centre of pressure for the wing is infinitely far aft). If it was just engine lift then this wouldn’t be a high AOA only issue, it would be present all the time.[/quote]

That all rings true to me, I do have some numbers based off a variant of the 737 (although I think its the Classic) from my stability and control course at university. I know exactly the cupboard and box they are in but my wife would never forgive me if I got them out...

morrisond wrote:
I think you can reasonably assume that if a Western Airline was found to have the same issues as pointed out in the NY Times article and they were not corrected they would be grounded.

People are not saying that training isn't an issue that needs sorting but what has that got to do with the increased risk associated with the MAX and its grounding? That's what this thread is about

morrisond wrote:
Why is it relevant? It sounds like Transport Canada might have the most reasonable solution for lifting the grounding (assuming the MAX doesn't have unaugmented aerodynamic issues). Scrap MCAS.

If MACS was required to pass the certification requirements for control forces then without MACS it does not pass the regulatory requirements for control forces. The fact that that Boeing implemented it in a quite frankly piss-poor way does mean that it is suddenly is OK to just ignore the control force regulations?

Morrisond please answer this, after the Battery fire issue on the 787, would it have been acceptable for Boeing to remove the battery altogether and simply bypass the regulation on power backup?
morrisond wrote:
However with that solution you would have to assume that more training is required. Would you trust those organizations (Lionair and ET) to provide that training?

I think it would be much better if Boeing built an aircraft that conformed to the regulations that the type certificate states rather than offering an aircraft that is inherently more risky than its predecessor.
Back the hierarchy of controls removing MACS would smack of "it was too hard to do it right so I just left it to the next guys in the chain"

Fred
Image
 
XRAYretired
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 3:33 pm

phollingsworth wrote:
PixelFlight wrote:
checklist350 wrote:

I still don't understand why there is no possibility to switch off just MCAS. The fact they need a modified plane seems to suggest this is still not possible with MCAS v2? Maybe this is because you aren't supposed to be able to turn off a safety feature?

Anyhow, I also don't understand why the manual trim can't be powered by a separate electric motor. And a fallback diesel generator for additional redundancy.

I agree that this is strange that the regulators don't require that the FCCs trim command can be disabled independently from the manual electrical trim. Should not be a so big modification, and look more in line with the MAX=NG Boeing goal.

The A350 use a stab trim system like you describes with 2 electrical motors, but the power source is either the electrical normal power (2 generators on each 2 engines + APU generator) or the emergency RAM air turbine generator, so 6 redundant power sources. There no manual trim wheels on the A350, just a stab trim backup switches. The irony is that the 737 classic did have two electrical motors, but not for redundancy, one was for the manual electric trim and the other for the FCCs AP.


Why Boeing went away for the two stage trim cutoff that the NGs had I am not clear on, it existed from the days of the two separate motors, but was carried through to the NGs. It allows a mush more graceful failover situation.

On redundancy, the A350s system is at most dual redundant, as that is the shallowest part of the chain. The power systems have a deeper depth, which may be sensible, but that doesn’t change the overall trim systems redundancy. On the 737 the trim redundancy is provided by dissimilar systems, the primary electric motor and the mk1 human. In principle having dissimilar systems is actually better as their failure modes are less likely to overlap. Note: the details of this are critical as an overstimulated crew member is probably the last thing you want as a the redundant system.

The switches go back to when there were two motors. . NG has only one motor and was subject to 'grandfathering' regs. I would suspect that the switches and internal wiring were left 'as is' minimising the number of changes affecting the crew. As far as I can tell, there are no NG procedures that require anything other than operating both switches at the same time. With MAX, a wiring modification was required to allow for the aft column microswitch to be by-passed with MCAS active, so they took the opportunity to 'tidy up' the wiring left over from classic but opted to leave the switches again to minimise the change affecting the crew - great grandfathering in action.

Ray
 
DenverTed
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 3:48 pm

XRAYretired wrote:
phollingsworth wrote:
PixelFlight wrote:
I agree that this is strange that the regulators don't require that the FCCs trim command can be disabled independently from the manual electrical trim. Should not be a so big modification, and look more in line with the MAX=NG Boeing goal.

The A350 use a stab trim system like you describes with 2 electrical motors, but the power source is either the electrical normal power (2 generators on each 2 engines + APU generator) or the emergency RAM air turbine generator, so 6 redundant power sources. There no manual trim wheels on the A350, just a stab trim backup switches. The irony is that the 737 classic did have two electrical motors, but not for redundancy, one was for the manual electric trim and the other for the FCCs AP.


Why Boeing went away for the two stage trim cutoff that the NGs had I am not clear on, it existed from the days of the two separate motors, but was carried through to the NGs. It allows a mush more graceful failover situation.

On redundancy, the A350s system is at most dual redundant, as that is the shallowest part of the chain. The power systems have a deeper depth, which may be sensible, but that doesn’t change the overall trim systems redundancy. On the 737 the trim redundancy is provided by dissimilar systems, the primary electric motor and the mk1 human. In principle having dissimilar systems is actually better as their failure modes are less likely to overlap. Note: the details of this are critical as an overstimulated crew member is probably the last thing you want as a the redundant system.

The switches go back to when there were two motors. . NG has only one motor and was subject to 'grandfathering' regs. I would suspect that the switches and internal wiring were left 'as is' minimising the number of changes affecting the crew. As far as I can tell, there are no NG procedures that require anything other than operating both switches at the same time. With MAX, a wiring modification was required to allow for the aft column microswitch to be by-passed with MCAS active, so they took the opportunity to 'tidy up' the wiring left over from classic but opted to leave the switches again to minimise the change affecting the crew - great grandfathering in action.

Ray

I thought on the NG one switch turns off Autopilot electric trim (STS and mach) and one switch turns off thumb toggle manual electric trim.
On the MAX they were changed to PRImary and Back Up.
 
morrisond
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 3:56 pm

flipdewaf wrote:
morrisond wrote:
I think you can reasonably assume that if a Western Airline was found to have the same issues as pointed out in the NY Times article and they were not corrected they would be grounded.

People are not saying that training isn't an issue that needs sorting but what has that got to do with the increased risk associated with the MAX and its grounding? That's what this thread is about


Fred


There are some saying that training doesn't need to be addressed. You are not one of them.

All civil aircraft have been certified with an assumed level of competence in the cockpit. If that level does not exist you have to change the certification standards and then re-certify all aircraft - or change the Training standards and ensure that pilots are in compliance with them.

Basically the MAX should not be allowed to Return to service if Pilot training standards and there compliance or lack thereof are allowed to remain as is or not allowed to return to service with airlines that cannot demonstrate that proficiency. It was certified to a different level of assumed competence that is not in evidence worldwide.

At this point I would suggest it should not be allowed to Return to service with Lionair until they can demonstrate they have fixed there training system. The jury is out on ET but it's not looking good.

Before MAX RTS - All other Airlines should have to at least have there pilots complete a flight from takeoff to touchdown using the manual trim wheel, and to demonstrate how to properly defeat the electric trim system and use said Manual trim system after being put in a position that is out of trim while in flight in the SIM. This does not need to be a MAX simulator.

I suggest this training be applied to all other 737 models or any other Airplane that has manual trim as a back up system within a reasonable period of time.

That is why training is relevant to the 737 grounding and it's eventual RTS. Fixing MCAS or deleting it plus an iPad course is not enough.
 
pune
Posts: 392
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 4:12 pm

morrisond wrote:

Sure the Airplane Manufacturers should focus on better safer designs and the airlines and training organizations should do what?

They aren't going help design the internal structure of a wing.

They should put put more resources behind ensuring that their pilots have the skills necessary to ensure crashes that have as contributing factors pilot error become less frequent.

There is a reason Airbus is opening Pilot training centres Worldwide - they do not want to suffer through what Boeing is going through.

They realize that no matter how safe there designs are inadequately trained pilots will figure out how to crash their planes.

Look at AirAsia crash 8501 - an Airbus 320 in 2014. All the recommendations that came out of that were basically ignored by Lionair - that is a great way to improve safety....


Could you share where is Airbus opening Pilot training centres, would be helpful to know that. If there is already a thread somewhere would be helpful as well.
 
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PixelFlight
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 25, 2019 4:21 pm

morrisond wrote:
flipdewaf wrote:
morrisond wrote:
I think you can reasonably assume that if a Western Airline was found to have the same issues as pointed out in the NY Times article and they were not corrected they would be grounded.

People are not saying that training isn't an issue that needs sorting but what has that got to do with the increased risk associated with the MAX and its grounding? That's what this thread is about


Fred


There are some saying that training doesn't need to be addressed. You are not one of them.

All civil aircraft have been certified with an assumed level of competence in the cockpit. If that level does not exist you have to change the certification standards and then re-certify all aircraft - or change the Training standards and ensure that pilots are in compliance with them.

Basically the MAX should not be allowed to Return to service if Pilot training standards and there compliance or lack thereof are allowed to remain as is or not allowed to return to service with airlines that cannot demonstrate that proficiency. It was certified to a different level of assumed competence that is not in evidence worldwide.

At this point I would suggest it should not be allowed to Return to service with Lionair until they can demonstrate they have fixed there training system. The jury is out on ET but it's not looking good.

Before MAX RTS - All other Airlines should have to at least have there pilots complete a flight from takeoff to touchdown using the manual trim wheel, and to demonstrate how to properly defeat the electric trim system and use said Manual trim system after being put in a position that is out of trim while in flight in the SIM. This does not need to be a MAX simulator.

I suggest this training be applied to all other 737 models or any other Airplane that has manual trim as a back up system within a reasonable period of time.

That is why training is relevant to the 737 grounding and it's eventual RTS. Fixing MCAS or deleting it plus an iPad course is not enough.

What you are talking about is a specific training for the 737-8/9 MAX that nobody have defined yet. So this is total speculation at this point of time. But even if this will be the case, Boeing would be required by the airlines to provides all the support to make that happen at the Boeing expense. Boeing might agree of not, but either ways, I see little incentive to make it effective and right instead of quick and cheap. But this is the subject of a new thread, right ?

I suggest Boeing to demo a 737-8 MAX with stab trim full nose down runaway at high speed and low altitude, just to see how effective the manual trim wheels are...
: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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