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889091
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 2:52 pm

I have a question about the OEM warranty for devices/appliances fitted on board the grounded MAXs.

With a RTS date still up in the air and the grounding approaching 1 year this March, what happens to the warranty 'clock' on the devices/appliances on board? Let's take the galley oven as an example. Let's assume the grounding has been lifted and Boeing implements the fix(es) and Airline XYZ receives the MAX exactly 1 year after the grounding was announced. 3 months later, the galley oven packs it in and XYZ contacts galley oven manufacturer ABC. Can ABC say, "sorry mate, our standard warranty is 12 months and you're 3 months out."

Also, how will Boeing get those stored birds back in the air once the grounding has been lifted? FIFO? LIFO?
Last edited by 889091 on Mon Dec 30, 2019 3:07 pm, edited 2 times in total.
 
XRAYretired
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 2:56 pm

TaromA380 wrote:
Even without the longitudinal instability problem that was underestimated during planning stage (and later led to Mcas), the whole Boeing engineering team economically optimized the Max program according to the requirements of their time (2011-2016). These requirements were made lot easier to achieve by that self-assessment in vigor back then.

Any engineering team would have done the same – assess at the mandatory requirements then build the product as cheap as possible to barely pass the requirements and get to the market.

The problem is that the Max was not build with today’s certification requirements in mind.

All that happened led to the vanishment of the self-certification miracle together with the obligation to recertify the plane in the old way. The Max is now kind of a stranger in a universe where it doesn’t fit and was never supposed to cope.

The regulators are asking today for a different plane than Boeing has built.

As far as I am aware, no requirements have changed from 2011 MAX baseline. If you know differently, please list them.

Ray
 
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par13del
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 3:01 pm

XRAYretired wrote:
As far as I am aware, no requirements have changed from 2011 MAX baseline. If you know differently, please list them.

Ray

So the reports about larger trim wheel, cables re-route, 16g seat installation are just folks blowing smoke? If these items were waived for the 2011 MAX baseline and are now required, is that a change or are we just being technical / pedantic?
 
morrisond
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 3:08 pm

asdf wrote:
JayinKitsap wrote:
It may be a big change in how to show compliance, not a change in rules. ....


this seems to be the point

boeing seems to be used to NOT show compliance to the regulator but only declare something as "compliant" by themselves
and as documentation only assessment, assumptions, comparative disclosures, comparability estimates ....
but no proofs of compliance

that brought boeing and its stakeholders in the last decades significant competitive advantages and massive savings
and it brought a higher risk of an accident and after a few decades now the trap has snapped shut with the 737MAx accidents

and the only thing what both, FAA and boeing does not seem to know is what of all those NOT proofed modifications of the 737 in the last decades need to be proofen now for the first time

from my point of view there are a view modifications and grandfatherings of the 737 series which are simply not proof able
the low-G hull for example can never be a grandfathering issue, can it?
you can grandfather a previous technical solution to make sure that the change to a new technical solution is not maybe unsafer as to keep the previous one
but how can it be more safe to keep a 5G hull if a 16G hull is the technical standard ....?
thats simply physics
it can never be more safe

so I can see very clearly where they have a problem in communication about what to proof ...


So please explain why the 737NG has a lower fatality rate than the A320 then?

As has been argued many times on this forum by others the 737NG has a perfectly acceptable safety record with most of the same grandfathering that the MAX has.
 
morrisond
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 3:21 pm

TaromA380 wrote:
Even without the longitudinal instability problem that was underestimated during planning stage (and later led to Mcas), the whole Boeing engineering team economically optimized the Max program according to the requirements of their time (2011-2016). These requirements were made lot easier to achieve by that self-assessment in vigor back then.

Any engineering team would have done the same – assess at the mandatory requirements then build the product as cheap as possible to barely pass the requirements and get to the market.

The problem is that the Max was not build with today’s certification requirements in mind.

All that happened led to the vanishment of the self-certification miracle together with the obligation to recertify the plane in the old way. The Max is now kind of a stranger in a universe where it doesn’t fit and was never supposed to cope.

The regulators are asking today for a different plane than Boeing has built.


Without evidence or reports on your last statement you are just speculating.

As far as anyone knows it does not have a longitudinal instability issue - the controls just get a little light when they shouldn't.

The plane will not leave its intended path without input - if it did then it would be unstable and totally not acceptable even with MCAS or full FBW in a commercial aircraft.

This is as far as anyone knows or has been reported. No MCAS testing - if it hasn't already been done by Boeing, the FAA or EASA - could have shown something different - but so far we have heard nothing.

Officially nothing has changed from the expectation that it could RTS in the next few months.

People are throwing a lot of speculation around as fact when we all know that Regulators will most likely be taking a lot of time off right now due to the Holidays and not making this priority #1.

Boeing did the firings at exactly the time you would do it to get as little as media attention as possible when many people are off or away for the Holidays.
 
lowbank
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 3:28 pm

par13del wrote:
XRAYretired wrote:
As far as I am aware, no requirements have changed from 2011 MAX baseline. If you know differently, please list them.

Ray

So the reports about larger trim wheel, cables re-route, 16g seat installation are just folks blowing smoke? If these items were waived for the 2011 MAX baseline and are now required, is that a change or are we just being technical / pedantic?


It could be the renewed vigour.

It could be a new set of eyes going over the information.

It can also be an 9ld set of eyes going over the information, no substitute for experience.
Every days a school day.
 
asdf
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 3:35 pm

Boeingphan wrote:
... If I'm the FAA hell yes I'm now going to make this as difficult as possible. ...


well
i don't buy it

this is such a big case
so many jobs are affected
i do not think there is anyone involved trying to block a procedure

but the FAA is covering their a** now
they look at the rules
and they enforce rules
they ask for documentation according to the rules
and if they dont get it they reject it

if this really happens now then its a hard way fuer boeing
they are not used to it
 
XRAYretired
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 3:37 pm

par13del wrote:
XRAYretired wrote:
As far as I am aware, no requirements have changed from 2011 MAX baseline. If you know differently, please list them.

Ray

So the reports about larger trim wheel, cables re-route, 16g seat installation are just folks blowing smoke? If these items were waived for the 2011 MAX baseline and are now required, is that a change or are we just being technical / pedantic?

16g requirement is relatively new and is not part of the requirement set for MAX and hence why it not being applied (though some think it should be). Rudder cable routing in relation to uncontained disk failure was waived acceptable for MAX. This stands unless and until FAA decide the original waiver was not based on sound reasoning - the question being re-asked now by some - (not least because Boeing based their submission partially on the performance of the CFM and the MAX engine is completely different with limited service data) no requirement change here, merely a suggestion of re-evaluation. Manual Trim has been re-assessed due to the preliminary findings of ET302 and other analysis that imply trim is not achievable in all areas of the operational envelope the results of which we have yet to gain any knowledge of, again, this is a re-evaluation of compliance with the MAX baseline requirement due to findings, not a change of requirement (actually nothing to do with size of the trim wheel per-se).

Would expect, nay demand, review of compliance based on the findings of crash investigations.

Ray
 
hivue
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 4:21 pm

XRAYretired wrote:
Would expect, nay demand, review of compliance based on the findings of crash investigations.


So no RTS until the final ET report is out and has been thoroughly evaluated by regulators?
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PW100
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 4:23 pm

morrisond wrote:
asdf wrote:
JayinKitsap wrote:
It may be a big change in how to show compliance, not a change in rules. ....

. . . . so I can see very clearly where they have a problem in communication about what to proof ...

So please explain why the 737NG has a lower fatality rate than the A320 then.


Perhaps, because in your numbers the oldest A320 is era 1988, and the oldest 737 is era 1998.

Newer generation planes usually are significantly more safe than older generation planes (the Max being the only odd one out).

If you would add the 737-300/400/500/600 series to your numbers, you'll find that the A320 series now all of a sudden has a lower fatality rate than the 737. So please explain that . . .

I have noticed you playing these numbers before, and I mentioned this to you before. But for some reason you continue to spread the misguided information.
Immigration officer: "What's the purpose of your visit to the USA?" Spotter: "Shooting airliners with my Canon!"
 
olle
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 4:26 pm

Revelation wrote:
MSPNWA wrote:
TTailedTiger wrote:
I give up. No one seems to want to answer my question of why the US would allow other nations to determine whether a US product can fly in US airspace.

Because they know they don't have a logical answer that doesn't mean the FAA effectively cedes its U.S. authority and gives up any chance of regaining the subjective "credibility".

It's funny you address this point by issuing loaded questions when the flip side of it is that EASA and other world regulators by your verbiage have been ceding their authority to FAA for decades and got badly burned by that via Boeing's unacceptably poor design and implementation of MCAS that FAA delegated authority over to Boeing.

MSPNWA wrote:
They apparently like the idea though, and it's no secret why that is. They hate the party that on the surface is hurt most by it.

I am anything but a Boeing hater. It's clear that Boeing's strategy of "might makes right" has failed. The CEO who implemented it is gone and the lawyer who advised it is also gone. If you don't believe me, maybe you will believe Boeing's BoD:

The Board of Directors decided that a change in leadership was necessary to restore confidence in the Company moving forward as it works to repair relationships with regulators, customers, and all other stakeholders.

Ref: https://investors.boeing.com/investors/ ... fault.aspx

Boeing went with the risky power politics approach and kept pushing it till the relationship with FAA and other regulators went beyond the breaking point. Now we are in the "repair" phase of the tragedy.

MSPNWA wrote:
In reality we are all already losing and will lose more the further down this path aviation takes.

Consensus winning out over power politics is hardly a loss. Power politics is a large part of what brought us two crashes. The sovereign FAA was bullied by Boeing into delegating authority for MCAS to it. Boeing then proceeded to give itself every benefit of the doubt to get the financial performance they were after. The result was tragedy, twice.

XRAYretired wrote:
'BitFlip' is a standing requirement for several decades. Compliance was always required, nothing changed except MCAS catastrophic failure modes were added to the design solution (and then 'hidden'). No regulations have been changed, the base requirements established at the time MAX design was proposed have not changed, the goal posts have been in place and unmoved since ~2011 for MAX.

There is one other change. FAA is doing its job this time.

In particular, some of the bits FAA chose to flip were related to enabling/disabling various aspects of MCAS. One would imagine Boeing would have done this test themselves long before FAA was involved. This leaves us that Boeing didn't test well enough, or maybe they did and misinterpreted or misunderstood the results, or maybe they did understand the results and chose to ignore their implications. Either way it's a bad look.



This was working for Boeing for too many years. Tanker deal, c-series and delta and FAA. The parameter they did not think of was Easa and china. Out of their control.
 
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scbriml
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 4:28 pm

par13del wrote:
So the reports about larger trim wheel, cables re-route, 16g seat installation are just folks blowing smoke?


Which reports are you referring to? Do you have links?
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JayinKitsap
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 4:29 pm

pune wrote:
JayinKitsap wrote:
It may be a big change in how to show compliance, not a change in rules. It would be pretty easy to agree on a rule set for the 737, as that has been established with the certifications previously completed. But keeping in control all of the Supplemental Type Certificates, with each identifying what alt was done and what parts were affected. Roughly there have been 5 major, and countless minor sets of changes to the model. Doing the Max certification it was identifying the changed items and doing the change analysis. In particular around systems, controls, and automation exactly how it was programmed, then altered many times, there is lots of bloat. Why Microsoft Word takes more computing power than my Finite Element Program does (it sucks in everything when the CALC button is pressed) but Google Docs barely takes any - a million changes, placeholder subroutines etc.

I work in facilities engineering, some in regulated facilities, where the work must be done right. When we renovate and add to an existing building we rarely trigger a seismic upgrade of the existing building, only need to meet in the new work as long as the existing is not overloaded or the load is reduced. The US Federal Government now with any purchase, long term lease, or major renovation / addition / change of use to go back and calculate the seismic performance of the whole building - original included. Yes the forces are dialed back to about 3/4 of a new building but everything needs to be checked and calculated. It is many times harder than doing a new building to the current code.

Suppose an element within MAX is evaluated for the change from the NG, well is the actual produced NG part the same as the original calculations and analysis checked it for back in 1967, with the calculations in serial lab books brought out from the vault, and the blueprints being truly blue for some of the parts that first were on the 707.

This explains how the issue of the odd data saves could have occurred, the save method changed slightly in some of the later programming from the earlier. It also puts some credence to the FAA wanting more data. It could be that the FAA just wants the system to be analyzed as a system, not a file box of paperwork showing how change Q modified change P which modified .... change A. The accidents brought home it is time to verify compliance by analysis anything altered in the MAX like a clean sheet, but only requiring it to show compliance with the 737 rule book. It probably hit Boeing back last summer, but the extent of the effort to do the direct analysis has slowed things down. In the case of the MAX, it is the right thing to do.


There have been lot of posts in this thread which are gems, this one is one of them. I wish the fora software we use was not so antiquated so could favorite it. Thank you for describing the complexity of certifying something which was outdated via modifications as current and the tests to see whether they make the system safer or not, although one could argue that even the best standards of safety are somewhat arbitrary in the sense that they were also bought as compromise .


Thank you.

All rules are compromises between safety and cost. We could require a Safety Factor of 2 instead of 1.5, but it would basically eliminate the available payload. Quite safe as no planes would be flying. Conversely, for temporary things we can use Safety Factor's as low as 1.2, and are willing to accept more failures. In the US we design for the 50 year snow event, 100 year wind, and live load, but 500 year seismic events a 100 year event has a 1% probability in any year.
 
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767333ER
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 4:33 pm

morrisond wrote:
asdf wrote:
JayinKitsap wrote:
It may be a big change in how to show compliance, not a change in rules. ....


this seems to be the point

boeing seems to be used to NOT show compliance to the regulator but only declare something as "compliant" by themselves
and as documentation only assessment, assumptions, comparative disclosures, comparability estimates ....
but no proofs of compliance

that brought boeing and its stakeholders in the last decades significant competitive advantages and massive savings
and it brought a higher risk of an accident and after a few decades now the trap has snapped shut with the 737MAx accidents

and the only thing what both, FAA and boeing does not seem to know is what of all those NOT proofed modifications of the 737 in the last decades need to be proofen now for the first time

from my point of view there are a view modifications and grandfatherings of the 737 series which are simply not proof able
the low-G hull for example can never be a grandfathering issue, can it?
you can grandfather a previous technical solution to make sure that the change to a new technical solution is not maybe unsafer as to keep the previous one
but how can it be more safe to keep a 5G hull if a 16G hull is the technical standard ....?
thats simply physics
it can never be more safe

so I can see very clearly where they have a problem in communication about what to proof ...


So please explain why the 737NG has a lower fatality rate than the A320 then?

As has been argued many times on this forum by others the 737NG has a perfectly acceptable safety record with most of the same grandfathering that the MAX has.

Maybe because it has served less years and in years of higher worldwide (for the most part) safety standards at airlines. How many times has an A320 crashed because of a design flaw or how many has it killed due to a design flaw. Almost all of these events in an A320 have been pilot error or intent.

Remember these are pernicious things you won’t see staring at numbers all day because the stats and numbers won’t show you this. A sheet of stats likely won’t be able to properly express the fact that the doors on the 737 are considered non-complaint by today’s standards because they require far too much force to open and are probably too small too. This is something you won’t see in crash rates, but it does make a difference when the thing does crash but not fatally.

And if the design was grandfathered from the 737-100 or even just the classic, should we not also grandfather those safety records as well since it is much the same design?

As for hull strength I agree with the previous reply. The 737 fuselage almost always crumbles in the same two places when it strikes the ground with some force, whether that be going off the end of a runway and down a slope or just slamming into the ground. Air Canada slams an A320 into the ground and power lines in Halifax and the wings get mutilated but the body actually stays in one piece.

It sounds like the FAA is having a good look at it for the first time and realizing that not looking at it before was a bad idea.
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asdf
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 4:34 pm

par13del wrote:
XRAYretired wrote:
As far as I am aware, no requirements have changed from 2011 MAX baseline. If you know differently, please list them.

Ray

So the reports about larger trim wheel, cables re-route, 16g seat installation are just folks blowing smoke? If these items were waived for the 2011 MAX baseline and are now required, is that a change or are we just being technical / pedantic?


this is not a change
it has turned out that boeing abused waiving in the past

because of the US congress decision they didn't need proof compliance with documents, they only need to promise the FAA that they have checked it and that they have the documentation and everything is done properly, and FAA had to accept that

the both 737MAX crashed

now they are asked to present those documents
but they can't
it was not true what they promised to the FAA
the documents never have been created

now they have to deliver documentation about their statements
and it seems like some of the promises are hard to follow now
 
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PW100
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 4:35 pm

morrisond wrote:
TaromA380 wrote:
. . .The regulators are asking today for a different plane than Boeing has built.

Without evidence or reports on your last statement you are just speculating.

As far as anyone knows it does not have a longitudinal instability issue - the controls just get a little light when they shouldn't.

. . . . it does not have a longitudinal instability issue is perhaps true. But then again, this then may also be true:
. . . . it does have a longitudinal stability issue in certain parts of the operational flight envelope.


Controls getting light is because of insufficient stability margin.
The more stable a platform (aerodynamically, mechanically, electrically, or whatever), the more effort is needed to take it out of the stable condition.

The less stable a platform (aerodynamically, mechanically, electrically, or whatever), the less effort is needed to take it out of the stable condition.
That effort could be control force (control column), but also atmospheric disturbance (turbulence).

The plane obviously has issues with its (approaching to) stall characteristics, which need to be addressed. Controls getting light is just a euphemism for insufficient (aerodynamic longitudial) stability.
Immigration officer: "What's the purpose of your visit to the USA?" Spotter: "Shooting airliners with my Canon!"
 
morrisond
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 4:37 pm

PW100 wrote:
morrisond wrote:
asdf wrote:

. . . . so I can see very clearly where they have a problem in communication about what to proof ...

So please explain why the 737NG has a lower fatality rate than the A320 then.


Perhaps, because in your numbers the oldest A320 is era 1988, and the oldest 737 is era 1998.

Newer generation planes usually are significantly more safe than older generation planes (the Max being the only odd one out).

If you would add the 737-300/400/500/600 series to your numbers, you'll find that the A320 series now all of a sudden has a lower fatality rate than the 737. So please explain that . . .

I have noticed you playing these numbers before, and I mentioned this to you before. But for some reason you continue to spread the misguided information.


Did I say 300/400/400/600? I said 737NG. I am not making the numbers up - People use those numbers all the time to support why the 737NG is absolutely safe with the current state of Pilot training.

In any case they are not materially different than the A320 - all the grandfathering has not been shown to make the NG any less safe.
 
asdf
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 4:42 pm

morrisond wrote:
asdf wrote:
JayinKitsap wrote:
It may be a big change in how to show compliance, not a change in rules. ....


this seems to be the point

boeing seems to be used to NOT show compliance to the regulator but only declare something as "compliant" by themselves
and as documentation only assessment, assumptions, comparative disclosures, comparability estimates ....
but no proofs of compliance

that brought boeing and its stakeholders in the last decades significant competitive advantages and massive savings
and it brought a higher risk of an accident and after a few decades now the trap has snapped shut with the 737MAx accidents

and the only thing what both, FAA and boeing does not seem to know is what of all those NOT proofed modifications of the 737 in the last decades need to be proofen now for the first time

from my point of view there are a view modifications and grandfatherings of the 737 series which are simply not proof able
the low-G hull for example can never be a grandfathering issue, can it?
you can grandfather a previous technical solution to make sure that the change to a new technical solution is not maybe unsafer as to keep the previous one
but how can it be more safe to keep a 5G hull if a 16G hull is the technical standard ....?
thats simply physics
it can never be more safe

so I can see very clearly where they have a problem in communication about what to proof ...


So please explain why the 737NG has a lower fatality rate than the A320 then?

As has been argued many times on this forum by others the 737NG has a perfectly acceptable safety record with most of the same grandfathering that the MAX has.


the 737NG has a solide safety record

but what is wrong with a 16G hull?
why did FAA demand a 16G hull long ago in the regulations and enforced it on every (foreign) certification all over the world if it is useless ?

the better is the enemy of the good
a 16G hull secures the PAX and crews a lot more then a 5G hull

(note: if a 737 breaks during a crash landing, it always collapses at a certain area of the hull. PAX pros avoid those seatrows as far as possible, for a good reason. that is the difference between a 5G hull and a 16G hull)

edit: sorry, i read backwards usually, I didn't get that 767333ER has brought exactly that point a few postings before ....
Last edited by asdf on Mon Dec 30, 2019 4:47 pm, edited 1 time in total.
 
morrisond
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 4:46 pm

PW100 wrote:
The less stable a platform (aerodynamically, mechanically, electrically, or whatever), the less effort is needed to take it out of the stable condition.
That effort could be control force (control column), but also atmospheric disturbance (turbulence).



So would you agree that sometimes Turbulence causes the controls to get a little lighter than allowed even with an aircraft that has stick force that increases as per regulation?

How many planes have crashed because of that?

This is something that Pilots have to be able to cope with and is ably demonstrated and experienced when you are piddling around in an 172 as it gets moved around a lot more than a 737.
 
planecane
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 4:50 pm

PW100 wrote:
morrisond wrote:
asdf wrote:

. . . . so I can see very clearly where they have a problem in communication about what to proof ...

So please explain why the 737NG has a lower fatality rate than the A320 then.


Perhaps, because in your numbers the oldest A320 is era 1988, and the oldest 737 is era 1998.

Newer generation planes usually are significantly more safe than older generation planes (the Max being the only odd one out).

If you would add the 737-300/400/500/600 series to your numbers, you'll find that the A320 series now all of a sudden has a lower fatality rate than the 737. So please explain that . . .

I have noticed you playing these numbers before, and I mentioned this to you before. But for some reason you continue to spread the misguided information.


The 10 year difference in service doesn't matter to the hull loss statistics since both have had well over a million departures. The 737NG is statistically as safe as the A320 series. There were pretty significant changes between the 737 classic series and the NG. The classic series was not as safe as the NG or A320. Part of that was due to the rudder reversal flaw that was mitigated pretty early in the NG service life but caused two hull losses in the classic. The glass cockpit might also be a factor that improves safety.
 
morrisond
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 5:00 pm

asdf wrote:
morrisond wrote:
asdf wrote:

this seems to be the point

boeing seems to be used to NOT show compliance to the regulator but only declare something as "compliant" by themselves
and as documentation only assessment, assumptions, comparative disclosures, comparability estimates ....
but no proofs of compliance

that brought boeing and its stakeholders in the last decades significant competitive advantages and massive savings
and it brought a higher risk of an accident and after a few decades now the trap has snapped shut with the 737MAx accidents

and the only thing what both, FAA and boeing does not seem to know is what of all those NOT proofed modifications of the 737 in the last decades need to be proofen now for the first time

from my point of view there are a view modifications and grandfatherings of the 737 series which are simply not proof able
the low-G hull for example can never be a grandfathering issue, can it?
you can grandfather a previous technical solution to make sure that the change to a new technical solution is not maybe unsafer as to keep the previous one
but how can it be more safe to keep a 5G hull if a 16G hull is the technical standard ....?
thats simply physics
it can never be more safe

so I can see very clearly where they have a problem in communication about what to proof ...


So please explain why the 737NG has a lower fatality rate than the A320 then?

As has been argued many times on this forum by others the 737NG has a perfectly acceptable safety record with most of the same grandfathering that the MAX has.


the 737NG has a solide safety record

but what is wrong with a 16G hull?
why did FAA demand a 16G hull long ago in the regulations and enforced it on every (foreign) certification all over the world if it is useless ?

the better is the enemy of the good
a 16G hull secures the PAX and crews a lot more then a 5G hull

(note: if a 737 breaks during a crash landing, it always collapses at a certain area of the hull. PAX pros avoid those seatrows as far as possible, for a good reason. that is the difference between a 5G hull and a 16G hull)

edit: sorry, i read backwards usually, I didn't get that 767333ER has brought exactly that point a few postings before ....


Nothing is wrong with the 16G rule - but as far as I'm aware (I just searched) - the 16G rule applies to the seats and their ability to remain intact and attached to the floor in the event of a crash. It has nothing to do with the strength of the hull.

I can find images of the nose snapping off an A320 as well as 737's crashing intact. The common denominator seems to be whether or not the aircraft hits something solid like an embankment.

The AC crash came to rest on a nice flat runway.
 
mjoelnir
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 5:00 pm

XRAYretired wrote:
par13del wrote:
XRAYretired wrote:
As far as I am aware, no requirements have changed from 2011 MAX baseline. If you know differently, please list them.

Ray

So the reports about larger trim wheel, cables re-route, 16g seat installation are just folks blowing smoke? If these items were waived for the 2011 MAX baseline and are now required, is that a change or are we just being technical / pedantic?

16g requirement is relatively new and is not part of the requirement set for MAX and hence why it not being applied (though some think it should be). Rudder cable routing in relation to uncontained disk failure was waived acceptable for MAX. This stands unless and until FAA decide the original waiver was not based on sound reasoning - the question being re-asked now by some - (not least because Boeing based their submission partially on the performance of the CFM and the MAX engine is completely different with limited service data) no requirement change here, merely a suggestion of re-evaluation. Manual Trim has been re-assessed due to the preliminary findings of ET302 and other analysis that imply trim is not achievable in all areas of the operational envelope the results of which we have yet to gain any knowledge of, again, this is a re-evaluation of compliance with the MAX baseline requirement due to findings, not a change of requirement (actually nothing to do with size of the trim wheel per-se).

Would expect, nay demand, review of compliance based on the findings of crash investigations.

Ray


The 16 g requirement is new? And perhaps the EICAS requirement is new too? Both requirements are from the 1980s. For all frames but the 737. Boeing of course got an exemption from the rules for the NG and than the MAX.
In regards to EICAS at least Boeing was crying about how expensive it would be to comply, I assume that Boeing cried when the NG was designed and again with the MAX.
I assume the 16 g requirement would have made the NG and than the MAX heavier, so an exemption was made.
How many years do you call a requirement or rule new? Both requirements are now more than 30 years old.

That the trim wheel was not working in all areas of operation was known since the Jurassic. And for the NG (and the MAX) it was allowed to reduce the authority of the wheel.

The exemption for the rudder cable protection was waived through by the FAA management, against the advise of the FAA technical staff.

A murkier way of certification is hardly imaginable.
 
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 5:02 pm

morrisond wrote:
PW100 wrote:
morrisond wrote:
So please explain why the 737NG has a lower fatality rate than the A320 then.


Perhaps, because in your numbers the oldest A320 is era 1988, and the oldest 737 is era 1998.
Newer generation planes usually are significantly more safe than older generation planes (the Max being the only odd one out).
If you would add the 737-300/400/500/600 series to your numbers, you'll find that the A320 series now all of a sudden has a lower fatality rate than the 737. So please explain that . . .
I have noticed you playing these numbers before, and I mentioned this to you before. But for some reason you continue to spread the misguided information.

Did I say 300/400/400/600? I said 737NG. I am not making the numbers up - People use those numbers all the time to support why the 737NG is absolutely safe with the current state of Pilot training.

In any case they are not materially different than the A320 - all the grandfathering has not been shown to make the NG any less safe.


No, you did not say 300/400/500/600. And that, exactly is my point. You are not comparing apples to apples.
You asked why the 737NG has a lower fatality rate than the A320. I provided you a very good explanation.

For the record, I'm in full agreement that grandfathering does not necessarily make planes less safe. In fact in many cases grandfathering is perfectly OK, sometimes perhaps even preferable over theoretical practice of new certification (there is no substitution for the real thing – flight hours in the bag). Grandfathering looks at millions of flight hours and demonstrates that reality has shown satisfactory level of safety. It becomes a bit more difficult when the safety requirements get tighter. The crucial thing is analysing and understanding differences to the new product.

Ironically, the thing that caused Max accidents and subsequent grounding (MCAS) has little to with grandfathering.
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 5:14 pm

https://lessonslearned.faa.gov/ll_main. ... ID=10#null

Quite interesting. I would be extremely surprised if the 16g seat didn't for instance require a stronger floor and floor track.
 
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 5:17 pm

mjoelnir wrote:
A murkier way of certification is hardly imaginable.


This happens with all Aircraft - lots of exceptions and equivalents are granted.

Here is the 337 Page Document from the A380 certification listing all it's deviations from the Standards.

https://www.easa.europa.eu/sites/defaul ... e%2003.pdf
 
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 5:21 pm

I just read several pages of this thread, with a new focus on FAA and how some believe they are not certifying fast enough the plane which has now fixed the issues that lead to the crashes.

Can we stop this, and more generally, stop the "someone else is guilty" talk (maintenance, pilots, geopolitics, ...)? Building airplanes is complex enough, and so is proving that they meet the certifications, or verifying those proofs. There's plenty of reasons why the process takes necessarily some amount of time. Remember that no one involved in this wants to make a mistake, because the consequences of a mistake would be fatal not just to passengers but also the airlines and the manufacturer.

So now everyone (Boeing included) are going through every possible situation and assessing them carefully. And it is not like you can just check a powerpoint presentation or a diagram and sign a checkmark for certification. It is actual work, actual engineering, science and human performance evaluation. It needs to be done.

One could potentially call for more openness in the process. I would personally enjoy it a lot, because it would give us aviation hobbyists interesting information. I applauded Ky's statements from EASE with regards to their requirements and their perceptions of the time plans. But obviously you could go *much* deeper as well. What's the performance of MAX when MCAS is offline? Can we see the stick force graphs? Can we see a diagram of the system architecture with the changes? And, in particular, I'd like to know more of the pilot performance tests and how pilots failed that recent tests where they were expected to perform a procedure but didn't. I have a feeling that would tell us a lot about what problems lie ahead. Perhaps MCAS 2.0 is still falling short of having a sufficiently understandable failure mode in a critical phase of flight, such that pilots know what to do with sufficient likelihood, while still allowing a normally-working MCAS to perform the function that it is required to do with given MAX's aerodynamics. Or maybe the sheer volume of scenarios and proofs is taking a lot of time. Anyway, we don't know.

But, I think different regulators may approach this differently, and also be forced to do so by outside forces such as legal reasons. I suspect FAA is in daily substantial interaction with a large number of people from both Boeing and FAA side, and they are making progress but also running into issues -- which could be about lack of documentation, but also about FAA disagreeing in some cases that Boeing's solution satisfies the regulations. But FAA has taken the approach that they are not the ones to inform outsiders about proprietary designs of manufacturers, so they are publicly silent. I think that's an OK approach as well, but leads to unnecessary speculation in this thread.
 
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 5:22 pm

PW100 wrote:
morrisond wrote:
PW100 wrote:

Perhaps, because in your numbers the oldest A320 is era 1988, and the oldest 737 is era 1998.
Newer generation planes usually are significantly more safe than older generation planes (the Max being the only odd one out).
If you would add the 737-300/400/500/600 series to your numbers, you'll find that the A320 series now all of a sudden has a lower fatality rate than the 737. So please explain that . . .
I have noticed you playing these numbers before, and I mentioned this to you before. But for some reason you continue to spread the misguided information.

Did I say 300/400/400/600? I said 737NG. I am not making the numbers up - People use those numbers all the time to support why the 737NG is absolutely safe with the current state of Pilot training.

In any case they are not materially different than the A320 - all the grandfathering has not been shown to make the NG any less safe.


No, you did not say 300/400/500/600. And that, exactly is my point. You are not comparing apples to apples.
You asked why the 737NG has a lower fatality rate than the A320. I provided you a very good explanation.

For the record, I'm in full agreement that grandfathering does not necessarily make planes less safe. In fact in many cases grandfathering is perfectly OK, sometimes perhaps even preferable over theoretical practice of new certification (there is no substitution for the real thing – flight hours in the bag). Grandfathering looks at millions of flight hours and demonstrates that reality has shown satisfactory level of safety. It becomes a bit more difficult when the safety requirements get tighter. The crucial thing is analysing and understanding differences to the new product.

Ironically, the thing that caused Max accidents and subsequent grounding (MCAS) has little to with grandfathering.


Others answered the NG safety record above.

Agreed on the rest.

If they had allowed one more exception as the Transport Canada employee speculated then we might never have been having this conversation.

Unless the MAX has some bizarre undisclosed handling issue other than what has so far been reported the MAX would probably have been a lot better off and have in reality about the same level of safety as the A320 and 737. No huge redesign needed.
 
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 5:25 pm

767333ER wrote:
It sounds like the FAA is having a good look at it for the first time and realizing that not looking at it before was a bad idea.

While we do have evidence of the ungrounding process taking longer than estimated, I don't know that we have evidence that this is due to FAA "having a good look at it for the first time".

We do have evidence that EASA is looking in to concerns about longitudinal stability in general and we know JOCB et al are looking into man-machine and related training issues but these all arise from the MCAS tragedy itself.

I haven't seen evidence that FAA or other regulators are considering "un-grandfathering" all these things people are writing about such as chair strength or cable routing, and if they are, why they would not dealt with on their own time line.

The delays could simply be what FAA's Dickson was complaining about, Boeing delivering incomplete submissions. I know that's not as cool or snarky a response as some here, but we do need to keep track what is known and what is speculation.
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 5:26 pm

AirlineCritic wrote:
I just read several pages of this thread, with a new focus on FAA and how some believe they are not certifying fast enough the plane which has now fixed the issues that lead to the crashes.

Can we stop this, and more generally, stop the "someone else is guilty" talk (maintenance, pilots, geopolitics, ...)? Building airplanes is complex enough, and so is proving that they meet the certifications, or verifying those proofs. There's plenty of reasons why the process takes necessarily some amount of time. Remember that no one involved in this wants to make a mistake, because the consequences of a mistake would be fatal not just to passengers but also the airlines and the manufacturer.

So now everyone (Boeing included) are going through every possible situation and assessing them carefully. And it is not like you can just check a powerpoint presentation or a diagram and sign a checkmark for certification. It is actual work, actual engineering, science and human performance evaluation. It needs to be done.

One could potentially call for more openness in the process. I would personally enjoy it a lot, because it would give us aviation hobbyists interesting information. I applauded Ky's statements from EASE with regards to their requirements and their perceptions of the time plans. But obviously you could go *much* deeper as well. What's the performance of MAX when MCAS is offline? Can we see the stick force graphs? Can we see a diagram of the system architecture with the changes? And, in particular, I'd like to know more of the pilot performance tests and how pilots failed that recent tests where they were expected to perform a procedure but didn't. I have a feeling that would tell us a lot about what problems lie ahead. Perhaps MCAS 2.0 is still falling short of having a sufficiently understandable failure mode in a critical phase of flight, such that pilots know what to do with sufficient likelihood, while still allowing a normally-working MCAS to perform the function that it is required to do with given MAX's aerodynamics. Or maybe the sheer volume of scenarios and proofs is taking a lot of time. Anyway, we don't know.

But, I think different regulators may approach this differently, and also be forced to do so by outside forces such as legal reasons. I suspect FAA is in daily substantial interaction with a large number of people from both Boeing and FAA side, and they are making progress but also running into issues -- which could be about lack of documentation, but also about FAA disagreeing in some cases that Boeing's solution satisfies the regulations. But FAA has taken the approach that they are not the ones to inform outsiders about proprietary designs of manufacturers, so they are publicly silent. I think that's an OK approach as well, but leads to unnecessary speculation in this thread.


Good post and I especially agree with the Openness part. That would be a good thing. Or at least at the end provide a blow by blow of why RTS took so long. I expect there may be a few books written about it.
 
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 5:31 pm

morrisond wrote:
PW100 wrote:
The less stable a platform (aerodynamically, mechanically, electrically, or whatever), the less effort is needed to take it out of the stable condition.
That effort could be control force (control column), but also atmospheric disturbance (turbulence).



So would you agree that sometimes Turbulence causes the controls to get a little lighter than allowed even with an aircraft that has stick force that increases as per regulation?

How many planes have crashed because of that?

This is something that Pilots have to be able to cope with and is ably demonstrated and experienced when you are piddling around in an 172 as it gets moved around a lot more than a 737.


That is actually a point that is even worse for the MAX. If your controls already get lighter in normal flight ops if you have to high of an AoA and turbulences even enhance said problem you have a really shitty design at your hand. Better the controls get naturally heavier to help even out such situations. In worst case and really high AoA and severe turbulence you might get really bad loads on the control even inverting the force gradient and with the MAX that might be too much especially when the pilots do not get type specific training for an occurrance specific on the MAX due to shortcommings in the design
 
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 5:33 pm

XRAYretired wrote:
par13del wrote:
XRAYretired wrote:
As far as I am aware, no requirements have changed from 2011 MAX baseline. If you know differently, please list them.

Ray

So the reports about larger trim wheel, cables re-route, 16g seat installation are just folks blowing smoke? If these items were waived for the 2011 MAX baseline and are now required, is that a change or are we just being technical / pedantic?

16g requirement is relatively new and is not part of the requirement set for MAX and hence why it not being applied (though some think it should be). Rudder cable routing in relation to uncontained disk failure was waived acceptable for MAX. This stands unless and until FAA decide the original waiver was not based on sound reasoning - the question being re-asked now by some - (not least because Boeing based their submission partially on the performance of the CFM and the MAX engine is completely different with limited service data) no requirement change here, merely a suggestion of re-evaluation. Manual Trim has been re-assessed due to the preliminary findings of ET302 and other analysis that imply trim is not achievable in all areas of the operational envelope the results of which we have yet to gain any knowledge of, again, this is a re-evaluation of compliance with the MAX baseline requirement due to findings, not a change of requirement (actually nothing to do with size of the trim wheel per-se).

Would expect, nay demand, review of compliance based on the findings of crash investigations.

Ray


I think it has become clear 737MAX was created using grandfathered design and requirements.
https://www.faa.gov/news/media/attachme ... t_2019.pdf

The FAA is updating some the requirements now. https://www.bloomberg.com/news/articles ... -s-737-max, https://www.faa.gov/aircraft/draft_docs ... ound-2.pdf

During design FAA granted Boeing exemptions to the rules, so the 737-8 could be certified not having the meet the latests requirements.
https://www.federalregister.gov/documen ... quirements
https://www.federalregister.gov/documen ... ng-company
https://www.federalregister.gov/documen ... ng-company
https://www.federalregister.gov/documen ... n-received
https://www.federalregister.gov/documen ... n-received

While FAA deceided to kill this grandfathering of meeting old requirements only 20 years ago https://www.flightglobal.com/faa-rules- ... 15.article, when the 737 MAX had to be certified, grandfathered was adopted as quick, smart, cost saving certification strategy again from 2011.

FAA specialist saw this happening & submitted their safety concerns, but FAA management ultimately overruled after Boeing objected. Boeing was in control, not FAA. https://www.seattletimes.com/business/b ... reamliner/

So apart from ensuring 737MAX meets all the requirements, question is who set / altered requirements, and why? FAA regulators need to take a step back and review this. And if they are told by congress to skip, burry and move on, somebody else will, publicly. https://www.forbes.com/sites/marisagarc ... 5a1bb37f5a
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 5:35 pm

PW100 wrote:
Ironically, the thing that caused Max accidents and subsequent grounding (MCAS) has little to with grandfathering.

Indeed, that's why I find it interesting that "un-grandfathering" is taking on a life of its own.

morrisond wrote:
This happens with all Aircraft - lots of exceptions and equivalents are granted.

Here is the 337 Page Document from the A380 certification listing all it's deviations from the Standards.

https://www.easa.europa.eu/sites/defaul ... e%2003.pdf

That would represent a lot of things to re-examine for "un-grandfathering" and I bet many aircraft have similar lists.

It seems to me MCAS has made for enough work without a bunch of un-grandfathering witch hunts.
Last edited by Revelation on Mon Dec 30, 2019 5:37 pm, edited 1 time in total.
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 5:35 pm

StTim wrote:
https://lessonslearned.faa.gov/ll_main.cfm?TabID=2&LLID=70&LLTypeID=10#null

Quite interesting. I would be extremely surprised if the 16g seat didn't for instance require a stronger floor and floor track.


Q.I. But when MCAS kicks in you might as well be in a wicker armchair - at least your brief flight would have a novelty value.
 
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 5:49 pm

mjoelnir wrote:
XRAYretired wrote:
par13del wrote:
So the reports about larger trim wheel, cables re-route, 16g seat installation are just folks blowing smoke? If these items were waived for the 2011 MAX baseline and are now required, is that a change or are we just being technical / pedantic?

16g requirement is relatively new and is not part of the requirement set for MAX and hence why it not being applied (though some think it should be). Rudder cable routing in relation to uncontained disk failure was waived acceptable for MAX. This stands unless and until FAA decide the original waiver was not based on sound reasoning - the question being re-asked now by some - (not least because Boeing based their submission partially on the performance of the CFM and the MAX engine is completely different with limited service data) no requirement change here, merely a suggestion of re-evaluation. Manual Trim has been re-assessed due to the preliminary findings of ET302 and other analysis that imply trim is not achievable in all areas of the operational envelope the results of which we have yet to gain any knowledge of, again, this is a re-evaluation of compliance with the MAX baseline requirement due to findings, not a change of requirement (actually nothing to do with size of the trim wheel per-se).

Would expect, nay demand, review of compliance based on the findings of crash investigations.

Ray


The 16 g requirement is new? And perhaps the EICAS requirement is new too? Both requirements are from the 1980s. For all frames but the 737. Boeing of course got an exemption from the rules for the NG and than the MAX.
In regards to EICAS at least Boeing was crying about how expensive it would be to comply, I assume that Boeing cried when the NG was designed and again with the MAX.
I assume the 16 g requirement would have made the NG and than the MAX heavier, so an exemption was made.
How many years do you call a requirement or rule new? Both requirements are now more than 30 years old.

That the trim wheel was not working in all areas of operation was known since the Jurassic. And for the NG (and the MAX) it was allowed to reduce the authority of the wheel.

The exemption for the rudder cable protection was waived through by the FAA management, against the advise of the FAA technical staff.

A murkier way of certification is hardly imaginable.

The question was in regard to changes to requirement for MAX since 2011 baseline = None?

Weather we like it or not, MG and MAX were 'grandfathered', so significant requirements that were not in place for classic will not be applied and will not be in the 2011 baseline or will have been waived in that timeframe. As you say, there may be grounds for reviewing rudder cable waiver but that is for the FAA to decide, as I said, the requirement has not changed.

Murky is a good word for the manual trim situation and re-assessment has been required due to findings (not a change in requirements). It may be that we seeing some 'double dealing' going on limitation/loss of electric trim being mitigated on the basis of manual trim, and limitation of manual trim mitigated by electric trim non-existing training, or something the like.

Ray
 
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 5:50 pm

I'm wondering if we're nearing the point where Boeing will throw in the towel on the MAX and simply move on to a newer narrowbody family. If ungrandfathering goes into effect in any meaningful way regarding the MAX recertification, that would mean more time grounded, more money, more upset customers, let alone what foreign regulators might do. It would be interesting to learn of Boeing has seriously considered this in terms of what combination of time and money lost would be sufficient to cause them to move on, or to at least recert the MAX's that are in existence and then quickly pivot to an all new design as fast as possible.
 
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 6:03 pm

mjoelnir wrote:

The 16 g requirement is new? And perhaps the EICAS requirement is new too? Both requirements are from the 1980s. For all frames but the 737. Boeing of course got an exemption from the rules for the NG and than the MAX.
.

The FAA initially wanted 16g seat retrofitted onto all a/c within a certain number of year, when the airlines balked at the cost, the FAA put on its financial hat and started making exceptions. I don't think it will help the discourse if we start talking about changes that were made to seats and infrastructure to make a/c 16g light...
 
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 6:16 pm

AirlineCritic wrote:
And, in particular, I'd like to know more of the pilot performance tests and how pilots failed that recent tests where they were expected to perform a procedure but didn't.

What we read in Jon's articles was that all pilots in that test recovered the a/c, it appears as if they used different means to do so...which would not be surprising since when the memory items were debated on this site in relation to MCAS, a number of folks said there was overlap, confusion etc.
Also according to the article, no agreement was yet in place on the updated training manuals.
 
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 6:37 pm

Revelation wrote:
PW100 wrote:
Ironically, the thing that caused Max accidents and subsequent grounding (MCAS) has little to with grandfathering.

Indeed, that's why I find it interesting that "un-grandfathering" is taking on a life of its own.

morrisond wrote:
This happens with all Aircraft - lots of exceptions and equivalents are granted.

Here is the 337 Page Document from the A380 certification listing all it's deviations from the Standards.

https://www.easa.europa.eu/sites/defaul ... e%2003.pdf

That would represent a lot of things to re-examine for "un-grandfathering" and I bet many aircraft have similar lists.

It seems to me MCAS has made for enough work without a bunch of un-grandfathering witch hunts.


t's not a witch hunt. It took 350 lives already. I think Congress / FAA / Boeing should fully implement recommendation of the Joint Authorities Technical Review (JATR) regarding Grandfathering design & requirements. Generalizing, ignoring or sidelining what went wrong on the 737MAX certification can have servere consequences for Boeing Safety, Quality, Integrity and ultimately, Continuity.

It's not about MCAS, it's about the corrupted process and the drivers behind it's certification. His role & approach in this process costed Muilenburg his job, his succesors better pay attention.

“But it is already abundantly clear that we will need to reform certification rules to enhance federal oversight and ensure proper firewalls between manufacturers and regulators so that a plane with a risk of catastrophic failure never slips past regulators again,” DeFazio said.

https://finance.yahoo.com/news/max-disa ... uyX5ATrqkK
Last edited by keesje on Mon Dec 30, 2019 6:39 pm, edited 1 time in total.
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 6:38 pm

par13del wrote:
mjoelnir wrote:

The 16 g requirement is new? And perhaps the EICAS requirement is new too? Both requirements are from the 1980s. For all frames but the 737. Boeing of course got an exemption from the rules for the NG and than the MAX.
.

The FAA initially wanted 16g seat retrofitted onto all a/c within a certain number of year, when the airlines balked at the cost, the FAA put on its financial hat and started making exceptions. I don't think it will help the discourse if we start talking about changes that were made to seats and infrastructure to make a/c 16g light...

Which helps explain where we are right now.

Global standards, inconsistently applied, with the disparity magnified by OEM's nimble use of 'precedents'.

An aircraft design which traces to the 50's and early 60's, much of the engineering knowledge and assumptions in the heads of retired or dead engineers, with multiple generations each using the previous model as THE new base case.

Add in self-regulation, with inadequate oversight by the regulator responsible........

Commercial aviation equivalent of Jenga?
 
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 6:43 pm

keesje wrote:
t's not a witch hunt. It took 350 lives already. I think Congress / FAA / Boeing should fully implement recommendation of the Joint Authorities Technical Review (JATR) regarding Grandfathering design & requirements. Generalizing, ignoring or sidelining what went wrong on the 737MAX certification can have servere consequences for Boeing Safety, Quality, Integrity and ultimately, Continuity.

It's not about MCAS, it's about the corrupted process and the drivers behind it's certification. His role & approach in this process costed Muilenburg his job, his succesors better pay attention.

So which is it, grandfathering, MCAS or the corrupt certification process, if it is the process, that is mostly out of the hands of the FAA, after years of out-sourcing to Boeing as mandated by congress, they cannot wake up on Monday morning and say go.....despite some of them wanting to flex their new found strength.
 
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 6:48 pm

smartplane wrote:
par13del wrote:
mjoelnir wrote:

The 16 g requirement is new? And perhaps the EICAS requirement is new too? Both requirements are from the 1980s. For all frames but the 737. Boeing of course got an exemption from the rules for the NG and than the MAX.
.

The FAA initially wanted 16g seat retrofitted onto all a/c within a certain number of year, when the airlines balked at the cost, the FAA put on its financial hat and started making exceptions. I don't think it will help the discourse if we start talking about changes that were made to seats and infrastructure to make a/c 16g light...

Which helps explain where we are right now.

Global standards, inconsistently applied, with the disparity magnified by OEM's nimble use of 'precedents'.

An aircraft design which traces to the 50's and early 60's, much of the engineering knowledge and assumptions in the heads of retired or dead engineers, with multiple generations each using the previous model as THE new base case.

Add in self-regulation, with inadequate oversight by the regulator responsible........

Commercial aviation equivalent of Jenga?


A few months ago we had this worrying revelations about the 2014 grandfathered certification of the crew allerting system.

Boeing’s argument in the document, which has not been previously reported, rested most basically on the long service history of the 737. At the time the MAX’s exception was granted, that included more than 300 million hours in the air, almost all accumulated on routinely safe flights.

However, Boeing’s analysis also had to deal with the fact that the 737’s record in the previous 10 years included three fatal crashes where crew alerting was a contributing factor: the 2005 Helios Airways crash in Greece that killed 121 people; the 2009 Turkish Airlines crash in Holland with nine fatalities; and the 2008 Aeroflot-Nord crash in Russia, in which 88 died.

Boeing convinced the FAA that it had dealt with the three distinct issues in each of those crashes.

The submission from Boeing then cited an estimate of the cost of full compliance at more than $10 billion.
...
In April 2014, the FAA accepted Boeing’s argument that for the MAX, the safety benefit of full compliance with the crew-alerting regulations was “not commensurate with the costs necessary to comply.”
https://www.seattletimes.com/business/boeing-aerospace/boeing-pushed-faa-to-arelax-737-max-certification-requirements-for-crew-alerts/

A chilling report on how safetyrequirements the 737MAX could not meet were dealt with.

Boeing had FAA in the pocket and remarkable Boeing-FAA certification events in that period have to be reviewed asap.
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par13del
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 6:48 pm

smartplane wrote:
Which helps explain where we are right now.

Global standards, inconsistently applied, with the disparity magnified by OEM's nimble use of 'precedents'.

An aircraft design which traces to the 50's and early 60's, much of the engineering knowledge and assumptions in the heads of retired or dead engineers, with multiple generations each using the previous model as THE new base case.

Add in self-regulation, with inadequate oversight by the regulator responsible........

Commercial aviation equivalent of Jenga?

If you were talking about keeping DC-3's flying I may 100% agree, but these 737 a/c are being built from scratch, everything going into them is new built, the parts are new and the assembly is new, it is not as if they are taking parts out of a/c in the boneyard.
 
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par13del
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 6:55 pm

keesje wrote:
Boeing had FAA in the pocket and remarkable Boeing-FAA certification events in that period have to be reviewed asap.

The bigger concern is what is the FAA doing about it, they already know about this since they were a part of the process, and this news was revealed months ago.
As I said in another post, what is new versus different reporters rehashing the same story.

How much of this did we already get during the 787 groundings and troubled development?
 
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keesje
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 7:12 pm

par13del wrote:
keesje wrote:
Boeing had FAA in the pocket and remarkable Boeing-FAA certification events in that period have to be reviewed asap.

The bigger concern is what is the FAA doing about it, they already know about this since they were a part of the process, and this news was revealed months ago.
As I said in another post, what is new versus different reporters rehashing the same story.


The fact it was revealed doesn't justifying ignoring it in any way?

This isn't Keeping Up with the Kardashians, where old shows are replaced by new ones & forgotten.

It hasn't, the CEO was fired, production stopped.

Timelines are unclear while specialist try to find a way out while it looks worse the better they look.

When Boeing started pushing like they became used to, Muilenburg was shown the door. Probably not by Boeing themselves.
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TaromA380
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 7:15 pm

XRAYretired wrote:
TaromA380 wrote:
Even without the longitudinal instability problem that was underestimated during planning stage (and later led to Mcas), the whole Boeing engineering team economically optimized the Max program according to the requirements of their time (2011-2016). These requirements were made lot easier to achieve by that self-assessment in vigor back then.

Any engineering team would have done the same – assess at the mandatory requirements then build the product as cheap as possible to barely pass the requirements and get to the market.

The problem is that the Max was not build with today’s certification requirements in mind.

All that happened led to the vanishment of the self-certification miracle together with the obligation to recertify the plane in the old way. The Max is now kind of a stranger in a universe where it doesn’t fit and was never supposed to cope.

The regulators are asking today for a different plane than Boeing has built.

As far as I am aware, no requirements have changed from 2011 MAX baseline. If you know differently, please list them.

Ray

Requirements are the same however there are at least two big entities that changed since 2011.

1. Several acknowledged but ignored requirements (FAA was in Boeing’s pocket at that time) seems to be no longer ignored today – see previous Keesje’s posts.

2. The self-assessment. For the same requirements, if you can declare yourself up to standards whatever you wish, versus everything being scrutinized by outsiders, the resulting product will be different. The Mcas affair and the two crashes were the result of this.

My theory is that the Max version built for 2011 requirements cannot be transformed economically wise into a version build for 2020 requirements.

It seems to me that this realization stuck the former CEO into “This cannot be possible, this cannot be possible” catharsis, doing nothing but waiting for political miracles to save the day, until he was eventually fired.
 
milhaus
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 7:19 pm

Exemptions are never good and there are too many of them on this airframe. FAA did big mistake to allow them on MAX. Thats why MAX is most unsafe and archaic aircraft built now.
 
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par13del
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 7:43 pm

keesje wrote:
par13del wrote:
keesje wrote:
Boeing had FAA in the pocket and remarkable Boeing-FAA certification events in that period have to be reviewed asap.

The bigger concern is what is the FAA doing about it, they already know about this since they were a part of the process, and this news was revealed months ago.
As I said in another post, what is new versus different reporters rehashing the same story.


The fact it was revealed doesn't justifying ignoring it in any way?

This isn't Keeping Up with the Kardashians, where old shows are replaced by new ones & forgotten.

It hasn't, the CEO was fired, production stopped.

Timelines are unclear while specialist try to find a way out while it looks worse the better they look.

When Boeing started pushing like they became used to, Muilenburg was shown the door. Probably not by Boeing themselves.

I will wait until folks start asking the congress and the FAA why these revelations that have been out PRIOR to the CEO termination and PRIOR to the announcement of a production shut down have been ignored or not publicly commented on, forcing additional reporters to once again make the revelations public, that seems to be the only thing that is working.
Did anything actually come out of the hearings on Capital Hill, any commitments, any new representatives sending letters to the FAA on not allowing the MAX to fly, Boeing to be reigned in, etc etc etc. transparency is needed by all involved, or just Boeing who have been told to shut up?
 
mjoelnir
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 9:36 pm

par13del wrote:
mjoelnir wrote:

The 16 g requirement is new? And perhaps the EICAS requirement is new too? Both requirements are from the 1980s. For all frames but the 737. Boeing of course got an exemption from the rules for the NG and than the MAX.
.

The FAA initially wanted 16g seat retrofitted onto all a/c within a certain number of year, when the airlines balked at the cost, the FAA put on its financial hat and started making exceptions. I don't think it will help the discourse if we start talking about changes that were made to seats and infrastructure to make a/c 16g light...


Yes quite understandable they made an exemption for the classic. EIS 4 years before the 16 g standard was introduced. They made the standard just in time to catch the A320.

Do you have an explanation why the NG got an exemption in 1997, launched 5 and EIS 11 years after the standard was introduced? Or now the 737 MAX, EIS in 2017, 29 years after the standard was introduced?
If we look at the launch of the MAX, that is in 2011. 23 years after the standard was introduced. Did this requirement catch Boeing and the FAA unaware?

The point to the 737 not fulfilling the standard, is not that the seats do not comply, but the flooring were the seats are installed is not strong enough in the 737 to fulfill the standard.
 
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WildcatYXU
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 9:49 pm

morrisond wrote:

Nothing is wrong with the 16G rule - but as far as I'm aware (I just searched) - the 16G rule applies to the seats and their ability to remain intact and attached to the floor in the event of a crash. It has nothing to do with the strength of the hull.

I can find images of the nose snapping off an A320 as well as 737's crashing intact. The common denominator seems to be whether or not the aircraft hits something solid like an embankment.

The AC crash came to rest on a nice flat runway.


Yes. After crashing into this: https://www.google.com/maps/@44.8635828 ... 312!8i6656
310, 319, 320, 321, 321N, 332, 333, 343, 345, 346, 732, 735, 73G, 738, 744, 752, 762, 763, 77L, 77W, 788, AT4, AT7, BEH, C402, CR2, CRA, CR9, DH1, DH3, DH4, E45, E75, E90, E95, F28, F50, F100, MD82, Saab 340, YAK40
 
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PW100
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Re: Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

Mon Dec 30, 2019 10:24 pm

morrisond wrote:
PW100 wrote:
The less stable a platform (aerodynamically, mechanically, electrically, or whatever), the less effort is needed to take it out of the stable condition.
That effort could be control force (control column), but also atmospheric disturbance (turbulence).


So would you agree that sometimes Turbulence causes the controls to get a little lighter than allowed even with an aircraft that has stick force that increases as per regulation?

There are several ways that can disturb a stable condition. Turbulence is certainly one of them. And yes, that does happen on other aircraft as well.
The problem with the Max is if that happens in certain parts of the operational flight envelope, then that is in addition to the lack of natural stability margin. And it is not evident that normal airline pilots are expected to be able to handle such situation.

This is something that Pilots have to be able to cope with and is ably demonstrated and experienced when you are piddling around in an 172 as it gets moved around a lot more than a 737.

That is all fine and well. But that still assumes that the aircraft has a certain stability margin and associated flight characteristics. Which the Max apparently doesn't have at certain parts of its flight envelope. Or in other words, to continue with your example, it would be OK for the Max as long as it does not meet that level of turbulence. Which is not a realistic scenario of course.
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