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frmrCapCadet
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 2:47 pm

PixelFlight wrote:
Revelation wrote:
The "whistleblower" story from a few weeks ago regarding adding synthetic airspeed for more safety provides documented evidence of that thought process.

I missed that part of the story: "Synthetic Air Data System" https://arc.aiaa.org/doi/abs/10.2514/1.C032177: :bouncy:
"A method for estimating the airspeed, angle of attack, and sideslip without using a conventional, pitot-static air data system is presented. The method relies on measurements from Global Positioning System, an inertial measurement unit, and a low-fidelity model of the aircraft’s dynamics, which are fused using two cascaded extended Kalman filters. In the cascaded architecture, the first filter uses information from the inertial measurement unit and Global Positioning System to estimate the aircraft’s absolute velocity and attitude. These estimates are used as the measurement updates for the second filter in which they are fused with the aircraft dynamics model to generate estimates of the airspeed, angle of attack and sideslip. Methods for dealing with the time and interstate correlation in the measurements coming from the first filter are discussed. Simulation and flight-test results of the method are presented. Simulation results show that the root mean square error of the airspeed estimate is less than 1  m/s1  m/s. The nominal errors from the flight test on airspeed, angle of attack, and sideslip are less than 2.5  m/s2.5  m/s, 2 deg, and 1 deg, respectively. Factors that affect the accuracy, including the implication and impact of using a low-fidelity aircraft model, are discussed."

Remember when I called (too often) for "flight dynamic predictive sensors filters" ? That so close ideas... :hyper:
I hope this will be mandatory in all new designs someday.


Any reason why low powered low range radar has not been added? GPS plus radar plus good digital charting would seem to provide almost absolute position and elevation, leaving only wind uncertainties affecting absolute speed. Recreational boats have much of that already and the cost is only a few thousand, reliability is just short of amazing.
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kalvado
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 3:01 pm

frmrCapCadet wrote:
PixelFlight wrote:
Revelation wrote:
The "whistleblower" story from a few weeks ago regarding adding synthetic airspeed for more safety provides documented evidence of that thought process.

I missed that part of the story: "Synthetic Air Data System" https://arc.aiaa.org/doi/abs/10.2514/1.C032177: :bouncy:
"A method for estimating the airspeed, angle of attack, and sideslip without using a conventional, pitot-static air data system is presented. The method relies on measurements from Global Positioning System, an inertial measurement unit, and a low-fidelity model of the aircraft’s dynamics, which are fused using two cascaded extended Kalman filters. In the cascaded architecture, the first filter uses information from the inertial measurement unit and Global Positioning System to estimate the aircraft’s absolute velocity and attitude. These estimates are used as the measurement updates for the second filter in which they are fused with the aircraft dynamics model to generate estimates of the airspeed, angle of attack and sideslip. Methods for dealing with the time and interstate correlation in the measurements coming from the first filter are discussed. Simulation and flight-test results of the method are presented. Simulation results show that the root mean square error of the airspeed estimate is less than 1  m/s1  m/s. The nominal errors from the flight test on airspeed, angle of attack, and sideslip are less than 2.5  m/s2.5  m/s, 2 deg, and 1 deg, respectively. Factors that affect the accuracy, including the implication and impact of using a low-fidelity aircraft model, are discussed."

Remember when I called (too often) for "flight dynamic predictive sensors filters" ? That so close ideas... :hyper:
I hope this will be mandatory in all new designs someday.


Any reason why low powered low range radar has not been added? GPS plus radar plus good digital charting would seem to provide almost absolute position and elevation, leaving only wind uncertainties affecting absolute speed. Recreational boats have much of that already and the cost is only a few thousand, reliability is just short of amazing.

Because wind uncertainty is a big enough factor to render GPS speed a moderately useless guesstimate for the airspeed.
There are some efforts to measure true air speed with other approaches; Doppler laser system was flight tested. As a best case scenario, such system would take a while before becoming mainstream...
Some predictive modeling using GPS and INS as an input is IMHO more feasible but would require a significant upgrade of plane electronics - so not going on 737.
 
morrisond
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 3:02 pm

Noshow wrote:
O'Leary said he is not sure to have any MAX back by summer 2020. That would put the return to service behind Q1 2020. This means behind the timeframe the Boeing CEO has said he would need to halt the MAX-production without renewed permit to fly. Is there something new brewing?


In the article Ryanair wasn't supposed to originally take the MAX until January. He now isn't expecting Delivery to March or April.

I know some MAX for Ryanair have been produced but they may not be the ones put back into service first just based on where they are in the Que to get modified. There first ones may be one's that roll off the assembly line.

This doesn't necessarily means he thinks there will be further delays in RTS overall. But it also may reflect EASA taking longer than the FAA.
 
mjoelnir
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 3:04 pm

Revelation wrote:
XRAYretired wrote:
An oft raised question - what about NG? on the way to being answered. Seems there are at least some regulator actions in that direction.

'.....It is understood that officials from the European Union Aviation Safety Agency (EASA) are conducting detailed checks on the NG with input from the Civil Aviation Authority (CAA)..........'

'........Officials are investigating the “angle-of-attack” sensor system on the NG after a thorough analysis of the same system on the Max, sources said. The system measures the angle of the oncoming air and is an important stall indicator. One source said that officials were investigating the design of the entire angle-of-attack sensor system, including software linked to it.
A source said: “The issues with the Max have caused them to look at the NG and there’s almost certain to be some action there. This is really positive. Rather than just saying, ‘All the NGs are flying safely, they have lots of flying hours,’ they are taking a proper look.”...…'

https://www.thetimes.co.uk/edition/news ... -qwzfjkpl5

Same logic should be applied to JT's operation rather than the silly logic of "they aren't crashing NGs so nothing to see there".

It'll be interesting to see if there will be a mandate to back-port the dual input checking of MAX back to NG, or implement a third (synthetic?) source for AoA data, and if so, what timeline will be mandated.

mjoelnir wrote:
The question is, is a look at the 737NG really needed. Sales of that frame have ended. It has a good safety record, though one could find quite a few things wrong with it.

That makes no sense. Why decide you need to replace exploding air bags only on new cars rather than mandate replacement on all models with the fault? NGs came off the production line this year and will be flying for decades to come.

mjoelnir wrote:
In regards to the MAX the situation is completely different. No reason to not replace systems that have been marginal already on the NG. The MAX is expected to be produced at least the next decade and perhaps the next two, so it should at least comply with today's rules.

More nonsense. Standards have been set (i.e. todays rules with documented exemptions) and they should be followed for both NG and MAX (and other aircraft too). In the case of MAX we now see the mistakes Boeing made in meeting the standards and they are being fixed. If NG made mistakes in its certification it too should be fixed, but as of yet we know of no such mistakes.


If you do not see the problem with, we got away with not complying to the rules for 40 years, so it will not matter that we do not comply with the rules the next 50 years, you do not see much.

The interface, not more compliant, is the man machine interface in regards to information and alarms regarding the airplane and engines. Boeing developed a new interface for the 757/767 and installed it in all following frames, it is called EICAS. The 737 classic, first flight 1981, got an exemption. The 737NG got an exemption.

As one of the serious issue identified in the KNKT final accident report regarding Lion Air Flight 610, in the JATR final findings and in the NSTC Safety Recommendation Report, is actually this christmas tree alarm system with a multitude of unsorted, unprioritized alarms.

Do you really recommend, to keep this exemption for the next frame, that will be in production the next 20 years and in flight at least the next fifty?

Is running on an exemption in a very serious safety relevant area for 40 years not enough? Does one has to keep it the next 50 years?
Last edited by mjoelnir on Mon Nov 04, 2019 3:17 pm, edited 1 time in total.
 
frmrCapCadet
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 3:11 pm

Wind uncertainty would be pretty low for the first 5-10 minutes of taking off and landing, at least at any major airport. Also see windy.com for what is now available world wide to everyone. Also nailing down position and altitude makes it easier to calculate/estimate speed. This leaves angle of attack also to estimate in event of instrument failures. But again, having a good handle on three makes the fourth easier.
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Revelation
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 3:23 pm

Edit: fix first quote...

majano wrote:
So are you now rendering events for Boeing? I have not seen any Boeing communication claiming this "on schedule but with a few weeks of slippage", unless I have missed it.

And you won't, but those of us who have worked for large corporations before have a better understanding of what the date actually means.

mjoelnir wrote:
If you do not see the problem with, we got away with not complying to the rules for 40 years, so it will not matter that we do not comply with the rules the next 50 years, you do not see much.

The interface, not more compliant, is the man machine interface in regards to information and alarms regarding the airplane and engines. Boeing developed a new interface for the 757/767 and installed it in all following frames, it is called EICAS. The 737 classic, first flight 1981, got an exemption. The 737NG got an exemption.

As one of the serious issue identified in the KNKT final accident report regarding Lion Air Flight 610, in the JATR final findings and in the NSTC Safety Recommendation Report, is actually this christmas tree alarm system with a multitude of unsorted, unprioritized alarms. Do you really recommend, to keep this exemption for the next frame, that will be in production the next 20 years and in flight at least the next fifty?

Is running on an exemption in a very serious safety relevant area for 40 years not enough? Does one has to keep it the next 50 years?

The NG is flying legally right now, otherwise it would be grounded.

If exemptions get pulled, lots of other airlines will also be grounded.

Pretty much every business jet there is would be grounded from what I am told, most of the RJs rely heavily on exemptions too.

If the outcome of the various reports is that EICAS is mandatory IMO there will be a timeline for compliance and will impact NG as well, but we have not crossed that bridge yet.
Last edited by Revelation on Mon Nov 04, 2019 3:30 pm, edited 1 time in total.
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PixelFlight
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 3:25 pm

kalvado wrote:
frmrCapCadet wrote:
PixelFlight wrote:
I missed that part of the story: "Synthetic Air Data System" https://arc.aiaa.org/doi/abs/10.2514/1.C032177: :bouncy:
"A method for estimating the airspeed, angle of attack, and sideslip without using a conventional, pitot-static air data system is presented. The method relies on measurements from Global Positioning System, an inertial measurement unit, and a low-fidelity model of the aircraft’s dynamics, which are fused using two cascaded extended Kalman filters. In the cascaded architecture, the first filter uses information from the inertial measurement unit and Global Positioning System to estimate the aircraft’s absolute velocity and attitude. These estimates are used as the measurement updates for the second filter in which they are fused with the aircraft dynamics model to generate estimates of the airspeed, angle of attack and sideslip. Methods for dealing with the time and interstate correlation in the measurements coming from the first filter are discussed. Simulation and flight-test results of the method are presented. Simulation results show that the root mean square error of the airspeed estimate is less than 1  m/s1  m/s. The nominal errors from the flight test on airspeed, angle of attack, and sideslip are less than 2.5  m/s2.5  m/s, 2 deg, and 1 deg, respectively. Factors that affect the accuracy, including the implication and impact of using a low-fidelity aircraft model, are discussed."

Remember when I called (too often) for "flight dynamic predictive sensors filters" ? That so close ideas... :hyper:
I hope this will be mandatory in all new designs someday.


Any reason why low powered low range radar has not been added? GPS plus radar plus good digital charting would seem to provide almost absolute position and elevation, leaving only wind uncertainties affecting absolute speed. Recreational boats have much of that already and the cost is only a few thousand, reliability is just short of amazing.

Because wind uncertainty is a big enough factor to render GPS speed a moderately useless guesstimate for the airspeed.
There are some efforts to measure true air speed with other approaches; Doppler laser system was flight tested. As a best case scenario, such system would take a while before becoming mainstream...
Some predictive modeling using GPS and INS as an input is IMHO more feasible but would require a significant upgrade of plane electronics - so not going on 737.

More inputs to the flight dynamic modem certainly give more accurate and reliable results, including to evaluate true air speed. From a very pragmatic point of view, aircraft have very big air "sensors" with there main wings if there will be equipped with appropriate measurement transducers to feed the data network. The same can be done, maybe more easily, with the control surfaces by measuring pressure on them. Like the advance in computing created an opportunity for full authority FBW system about 4 decades ago, I think that the actual advance in electronic create an opportunity for far more aircraft introspection and real time processing of an accurate and reliable flight dynamic model.
: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:
 
benbeny
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 3:32 pm

Noshow wrote:
O'Leary said he is not sure to have any MAX back by summer 2020. That would put the return to service behind Q1 2020. This means behind the timeframe the Boeing CEO has said he would need to halt the MAX-production without renewed permit to fly. Is there something new brewing?

Maybe he's talking about EASA and EASA probably won't give automatic green light after FAA
 
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Polot
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 3:35 pm

majano wrote:
Revelation wrote:
scbriml wrote:

On schedule but with a few weeks of slippage?

If you’re not in PR you may have missed your vocation in life! :wink2:

Sorry but of course almost every schedule I've seen is the most optimistic rendering of events, designed to keep the pressure on the people in the trenches.

I'd expect no different in this case.

As I wrote earlier, if he said Q1 2020 everyone involved would recaliabrate and it would be no earlier than Q1 2020.

So are you now rendering events for Boeing? I have not seen any Boeing communication claiming this "on schedule but with a few weeks of slippage", unless I have missed it.

He got that because Boeing said they would submit the final fix documentation to the FAA by the end of September. We know they submitted sometime in October, hence following the communicated timeline with a few weeks of slippage.
 
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smithbs
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 4:10 pm

keesje wrote:
Why is nobody asking for a formal Boeing responds to the JATR recommendations? The Senate could have asked.


The report had a section on actions that were or are currently being taken by each party, and Boeing had items listed in that section. So that could be construed as Boeing's response - they identified tasks and are working on it.

Revelation wrote:
Boeing is still maintaining a "plausible deniability" defense that seems to be still intact.


Yeah, and after reading the Indonesian report I think that defense is a bit stronger than I originally thought.

Revelation wrote:
As I wrote earlier, if he said Q1 2020 everyone involved would recaliabrate and it would be no earlier than Q1 2020.


Are you saying that if a boss gives a due date of Q1 then it's going to be delivered no earlier than March 31st at 11:59 pm? :lol:
 
mrbots
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 4:42 pm

Anyone know if the one's coming out of the factory are updated with 2.0 (and any other changes) on the hopes it gets approved as is?
 
mjoelnir
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 4:43 pm

Revelation wrote:
Edit: fix first quote...

majano wrote:
So are you now rendering events for Boeing? I have not seen any Boeing communication claiming this "on schedule but with a few weeks of slippage", unless I have missed it.

And you won't, but those of us who have worked for large corporations before have a better understanding of what the date actually means.

mjoelnir wrote:
If you do not see the problem with, we got away with not complying to the rules for 40 years, so it will not matter that we do not comply with the rules the next 50 years, you do not see much.

The interface, not more compliant, is the man machine interface in regards to information and alarms regarding the airplane and engines. Boeing developed a new interface for the 757/767 and installed it in all following frames, it is called EICAS. The 737 classic, first flight 1981, got an exemption. The 737NG got an exemption.

As one of the serious issue identified in the KNKT final accident report regarding Lion Air Flight 610, in the JATR final findings and in the NSTC Safety Recommendation Report, is actually this christmas tree alarm system with a multitude of unsorted, unprioritized alarms. Do you really recommend, to keep this exemption for the next frame, that will be in production the next 20 years and in flight at least the next fifty?

Is running on an exemption in a very serious safety relevant area for 40 years not enough? Does one has to keep it the next 50 years?

The NG is flying legally right now, otherwise it would be grounded.

If exemptions get pulled, lots of other airlines will also be grounded.

Pretty much every business jet there is would be grounded from what I am told, most of the RJs rely heavily on exemptions too.

If the outcome of the various reports is that EICAS is mandatory IMO there will be a timeline for compliance and will impact NG as well, but we have not crossed that bridge yet.


When did I ask or comment on the 737NG flying on? I am absolutely not interested what and if something is done with the 737NG. I am just against the silly argument that, because it was this way on the NG, it should be kept on the MAX.

You get exited about about the dangers of Lion Air pilots and maintenance, but when it gets to one of the main points that caused this accident, than you go full tilt for doing nothing. I assume because that could inconvenience the blessed mother Boeing.

It may well be that there other exemptions for other frames and on the business frames the people who buy them have to judge the risks. But I dare you to show me one frame build today, that gets exactly this exemption from the rules, like the 737 gets.
 
BEG2IAH
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 5:10 pm

HELSINKI (Reuters) - Boeing's <BA.N> grounded 737 MAX airliner is likely to return to service in Europe during the first quarter of 2020, the head of the European Union Aviation Safety Agency (EASA) said on Monday.

While the European regulator expects to give its approval in January, preparations by national authorities and airlines may delay the resumption of commercial flights by up to another two months, EASA executive director Patrick Ky indicated.

Source: https://finance.yahoo.com/news/boeings-grounded-max-seen-resuming-170540590.html
Flying at the cruising altitude is (mostly) boring. I wish all flights were nothing but endless take offs and landings every 10 minutes or so.
 
AABusDrvr
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 5:14 pm

keesje wrote:
asdf wrote:
mjoelnir wrote:
The question is, is a look at the 737NG really needed. Sales of that frame have ended. It has a good safety record, though one could find quite a few things wrong with it.


there have been a few 737NG disasters with a trim context
but as far as there are no more of them coming up, it would probably be unreasonable to take any action on the NGs

the 737MAX ... other story ... it think it is unsafe because of its aerodynamic attidudes
it should not fly


Read through e.g. Turkish 1951, what happened, lack of redundancy, confusing emergency systems and how it was handeld. (Wait/hide behind not yet available official investigation reports as long as possible, indirectly question pilots/ training, play the media, give discounts, make changes silently).

Or how Boeing was able to keep NG crahes involving redundancy and human interfaces out of statistic to enable grandfathering of requirements and design for the 737MAX. With a (now) unsurprizing cooperative FAA.

Instead of taking the claimed excellent 737NG safety record as starting point, reason to by-pass, experts look at those NG records again, including incidents, accidents, re-tagging them for relation with insights they got more recently. That's what we pay them for.

Independent reviews of previous projects are logical here, for independent authorities taking themselves seriously.

Why is nobody asking for a formal Boeing responds to the JATR recommendations? The Senate could have asked.



Turkish 1951 didn't have anything to do with human interface or confusing emergency systems. Systems redundancy possibly, in a single radar altimeter feeding data to the auto throttles. But an automation dependent crew sat there for over a minute and a half, with the throttles at idle, while the airplane slowed down, and didn't do anything, until the stick shaker went off. Thats a pretty hard sell to blame Boeing, or the 737 for that one. Those guys were way behind the airplane, I don't care how automated it is, someone still has to be paying attention to what's going on.
 
kayik
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 5:27 pm

Noshow wrote:
O'Leary said he is not sure to have any MAX back by summer 2020. That would put the return to service behind Q1 2020. This means behind the timeframe the Boeing CEO has said he would need to halt the MAX-production without renewed permit to fly. Is there something new brewing?


Now, the head of IATA, Alexandre de Juniac, says he does not expect to see the 737 Max back in the skies until August.
 
Noshow
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 5:36 pm

I tell you there is something going on regarding the authorities MAX-reevaluation.
They seem to require something else that takes time? Hardware changes?
Will the production line need to be halted?
 
BEG2IAH
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 5:51 pm

In EASA head Ky's own words...

The European watchdog hopes to complete a detailed software review by the end of this month, followed by December flight tests "if everything goes well", he added.
Source, again: https://finance.yahoo.com/news/boeings-grounded-max-seen-resuming-170540590.html

What are you guys (kayik, KlimaBXsst, Noshow) talking about?
Last edited by BEG2IAH on Mon Nov 04, 2019 5:55 pm, edited 1 time in total.
Flying at the cruising altitude is (mostly) boring. I wish all flights were nothing but endless take offs and landings every 10 minutes or so.
 
Noshow
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 5:55 pm

Current statements by the Ryanair CEO and the IATA-Boss about possible delays with no MAX aircraft available by summer.
 
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keesje
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 5:57 pm

AABusDrvr wrote:
keesje wrote:
asdf wrote:

there have been a few 737NG disasters with a trim context
but as far as there are no more of them coming up, it would probably be unreasonable to take any action on the NGs

the 737MAX ... other story ... it think it is unsafe because of its aerodynamic attidudes
it should not fly


Read through e.g. Turkish 1951, what happened, lack of redundancy, confusing emergency systems and how it was handeld. (Wait/hide behind not yet available official investigation reports as long as possible, indirectly question pilots/ training, play the media, give discounts, make changes silently).

Or how Boeing was able to keep NG crahes involving redundancy and human interfaces out of statistic to enable grandfathering of requirements and design for the 737MAX. With a (now) unsurprizing cooperative FAA.

Instead of taking the claimed excellent 737NG safety record as starting point, reason to by-pass, experts look at those NG records again, including incidents, accidents, re-tagging them for relation with insights they got more recently. That's what we pay them for.

Independent reviews of previous projects are logical here, for independent authorities taking themselves seriously.

Why is nobody asking for a formal Boeing responds to the JATR recommendations? The Senate could have asked.



Turkish 1951 didn't have anything to do with human interface or confusing emergency systems. Systems redundancy possibly, in a single radar altimeter feeding data to the auto throttles. But an automation dependent crew sat there for over a minute and a half, with the throttles at idle, while the airplane slowed down, and didn't do anything, until the stick shaker went off. Thats a pretty hard sell to blame Boeing, or the 737 for that one. Those guys were way behind the airplane, I don't care how automated it is, someone still has to be paying attention to what's going on.


I think it had to do with redundancy, allerting systems, human interfaces. A decade ago Boeing got away with it. Different times.The Turkish aircraft had to decent/ slow to reach the flight path. The crew saw not nothing strange in the throttles pulling back automatically, they were still doing the checklists.

They didn't see the aircraft was in landing mode, flaring because it was -8ft sea level. The alert system was telling the crew to lower the landing gear. A situation like this, stalling the aircaft, diving into ground could not happen on a 787 or 777, because they are designed top down and meet the latest standards.

The 737 NG does not, using grandfathered requirements from the sixties and fragmented system qualification, missing out on (human) interfaces. At least that is what JATR thinks.

JATR Recommendations 1-4, 7 that go far further than the 737MCAS system.

https://www.skybrary.aero/index.php/The_Joint_Authorities_Technical_Review_(JATR)_-_Boeing_737_MAX_Flight_Control_System#Recommendations
Last edited by keesje on Mon Nov 04, 2019 6:02 pm, edited 1 time in total.
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asdf
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 5:57 pm

Noshow wrote:
I tell you there is something going on regarding the authorities MAX-reevaluation.
They seem to require something else that takes time? Hardware changes?


i think boeing simply needs time to find a way to get the 737MAX aerodynamical neutral
like any airliner in the 21st century should be

the "augmentation" story has burst
the regulators know that the MAX pitches up under thrust and you can not certify a plane with that erronous attitudes
at least not if there is not a full fly-by-wire system intergrated to compensate the aerodynamical defect

they cant integrate a full FBW system because of grandfathering
they cant dispense the grandfathering privileges because the 737 can not recertified to todays standard

game over
 
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par13del
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 6:19 pm

mrbots wrote:
Anyone know if the one's coming out of the factory are updated with 2.0 (and any other changes) on the hopes it gets approved as is?

Since 2.0 has not been approved, it cannot be put through the production line, contrary to a general belief, Boeing cannot do what they want to when they want to with an a/c that is in production without approval and certification from the FAA.
If they had that power, do you really believe the MAX would still be grounded costing them millions per day?
Last edited by par13del on Mon Nov 04, 2019 6:25 pm, edited 1 time in total.
 
morrisond
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 6:20 pm

The head of AA's flight attendants is on CNBC in a minute or so
 
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par13del
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 6:25 pm

asdf wrote:
i think boeing simply needs time to find a way to get the 737MAX aerodynamical neutral
like any airliner in the 21st century should be

So rather than halt production of an a/c that they will have to physically modify, they continue to spit them out at 40+ per month?
If hardware changes are required and Boeing knows it they will look even more foolish for continuing to produce the frames that will not be able to fly.

Now if you want to say that the regulator and authorities will mandate a hardware change be introduced into the production line effective XXXXX.......
 
2175301
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 6:35 pm

Alfons wrote:
tedzbear wrote:
Why is it taking so long for Boeing to get the software fix ready for certification?


because they want to make it sure that it's also certifiable by regulators which are not bought by them.


There are two aspects to why the delays: MCAS version 2 was apparently fully tested in June; and had the regulators stopped there it is likely that the 737Max would have likely returned to flight status by the end of August.

However, the regulators were concerned with other things - and one of the things they did was to run a test on what would happen if by chance there were 5 specific radiation induced bit flips in the flight computer. Now the odds of that happening are extreemly remote (and well rarer than any certification standard): I've had it explained that 1 bit flip is clearly possible within the certification standard. 2 might occur. 5 no way.

Based on a statisticaly virtually improbably induced failure in the flight control computer... the regulators then told Boeing that they would have to fix that too....

My understanding is that the real reason for this was by having Boeing update the flight control computer software and operation to closer to modern standards that it would also reduce other issues - and all the direct treaty involved regulator agencies (Brazil, Canada, EASA) felt that was a desirable thing to do. China is not involved in this international agency treaty group; but I understand has been granted observer and comment rights so that they are at least knowledgeable on the intricacies and can provide input (but not demand changes as Brazil, Canada, and EASA can).

Boeing agreed - and it appears at this point that this "upgrade the flight control computer software" has delayed Max reentry by about 6 months (new test flights in November to validate the new flight control computer software). There has been some slippage due to ensuring that Boeing and the treaty country regulator agencies are all on board with the final software's purpose and expected test results.

Based on everything I am hearing - it is indeed likely that the FAA will in fact certify the 737Max with the upgrades developed yet in 2019 (4th quarter).

EASA and the other regulators have always had in their treaties the responsibility to validate any specific features significantly different than FAA standards and to set their own training requirements. EASE has just indicated that they believe it will take them no more than a month after FAA approval (January with a December FAA approval).

Since Brazil, Canada, and EASA regulator agencies have been heavily involved with the FAA and Boeing on the issue, the fix, the standards for return to service... I anticipate no surprises from anyone unless the FAA identifies a new issue that has to be resolved before re-certification. China is unlikely to have any serious issues - as I am sure that they are trying to build good relations with this existing treaty group as they would like to be a member in the future. Of course, each national agency (or EASA for much of Europe) has their own rights and responsibilities in relationship to certifying the 737Max for service in their countries and specifying training requirements. In reality, most of the rest of the world just accepts the certification and training requirements from Brazil, Canada, EASA, and the FAA in the United states.

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

Mon Nov 04, 2019 6:37 pm

"there has been a lot of work done on the design of the software," Ky said. But he added: "We think there is still some work to be done".

How has Boeing not finished this yet? Is this last bit of work on the software so difficult that maybe it is not solvable?
 
KlimaBXsst
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 6:44 pm

LondonAero wrote:
...How has Boeing not finished this yet? Is this last bit of work on the software so difficult that maybe it is not solvable?


Exactly
Aesthetically the A 340 got it right!
 
checklist350
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 6:47 pm

Revelation wrote:
XRAYretired wrote:
An oft raised question - what about NG? on the way to being answered. Seems there are at least some regulator actions in that direction.

'.....It is understood that officials from the European Union Aviation Safety Agency (EASA) are conducting detailed checks on the NG with input from the Civil Aviation Authority (CAA)..........'

'........Officials are investigating the “angle-of-attack” sensor system on the NG after a thorough analysis of the same system on the Max, sources said. The system measures the angle of the oncoming air and is an important stall indicator. One source said that officials were investigating the design of the entire angle-of-attack sensor system, including software linked to it.
A source said: “The issues with the Max have caused them to look at the NG and there’s almost certain to be some action there. This is really positive. Rather than just saying, ‘All the NGs are flying safely, they have lots of flying hours,’ they are taking a proper look.”...…'

https://www.thetimes.co.uk/edition/news ... -qwzfjkpl5

Same logic should be applied to JT's operation rather than the silly logic of "they aren't crashing NGs so nothing to see there".

It'll be interesting to see if there will be a mandate to back-port the dual input checking of MAX back to NG, or implement a third (synthetic?) source for AoA data, and if so, what timeline will be mandated.

mjoelnir wrote:
The question is, is a look at the 737NG really needed. Sales of that frame have ended. It has a good safety record, though one could find quite a few things wrong with it.

That makes no sense. Why decide you need to replace exploding air bags only on new cars rather than mandate replacement on all models with the fault? NGs came off the production line this year and will be flying for decades to come.

mjoelnir wrote:
In regards to the MAX the situation is completely different. No reason to not replace systems that have been marginal already on the NG. The MAX is expected to be produced at least the next decade and perhaps the next two, so it should at least comply with today's rules.

More nonsense. Standards have been set (i.e. todays rules with documented exemptions) and they should be followed for both NG and MAX (and other aircraft too). In the case of MAX we now see the mistakes Boeing made in meeting the standards and they are being fixed. If NG made mistakes in its certification it too should be fixed, but as of yet we know of no such mistakes.


NG is basically not in production anymore as an airliner (I believe KLM took delivery of the last NG model?)

What you and espeically MSPNWA fail to see or admit is that in any industry, be it automotive, housing or aerospace there are different set of rules for exisiting products in service and those being manufactured. Cars are the clearest example where basically every car driving around older than 10 yrs probably would be banned from selling today.

For housing the same; what is perfectly acceptable in a current house, and what even might be acceptable for reconstructed/repurposed housing (different set of rules again) would not be acceptable for new housing.

So possible changes to
1. the trim wheel
2. the number of AoA vanes
3. missing EICAS / acceptable alerting system
4. etc.

for the MAX to be certified, do not in itself mean the NG would need to adhere to them as well. Only if there was found a serious security flaw that would violate the rules on which it was certified does the NG need to be changed as well.

If it followed that all in service airliners would need to adhere to all the latest regulations, no airplane older than the 350XWB, 220 and 787 would be allowed to fly.
 
LondonAero
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 6:48 pm

Can someone send over a link to the comments from IATA / Alexandre de Juniac? Thanks
 
kayik
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 7:10 pm

LondonAero wrote:
Can someone send over a link to the comments from IATA / Alexandre de Juniac? Thanks

https://www.scmp.com/news/hong-kong/tra ... summer-air
 
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Polot
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 7:13 pm

kayik wrote:
LondonAero wrote:
Can someone send over a link to the comments from IATA / Alexandre de Juniac? Thanks

https://www.scmp.com/news/hong-kong/tra ... summer-air

That is from May 2019. He was talking about summer 2019, not summer 2020.
 
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par13del
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 7:17 pm

2175301 wrote:
However, the regulators were concerned with other things - and one of the things they did was to run a test on what would happen if by chance there were 5 specific radiation induced bit flips in the flight computer. Now the odds of that happening are extreemly remote (and well rarer than any certification standard): I've had it explained that 1 bit flip is clearly possible within the certification standard. 2 might occur. 5 no way.

Based on a statisticaly virtually improbably induced failure in the flight control computer... the regulators then told Boeing that they would have to fix that too....

My understanding is that the real reason for this was by having Boeing update the flight control computer software and operation to closer to modern standards that it would also reduce other issues -

I am not doubting anything that you have posted, but it raises more questions in my mind.
If there are other issues that would bring the a/c up to standards that the other regulators want, why hide them behind some failure mode that is virtually impossible as justification, simply state the items and make them a condition of ungrounding. I can see Boeing pushing to have the changes introduced in the production line, but as the a/c was already grounded due to fatal crashes, they would not have much if any leverage for such a demand.
The concern here is whether the regulators are now introducing some items which were / are not in the relevant manuals and these will become more things that are being hidden from the operators? It can't be ok for one side to hide versus the other.
Last edited by par13del on Mon Nov 04, 2019 7:19 pm, edited 1 time in total.
 
asdf
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 7:17 pm

par13del wrote:
asdf wrote:
i think boeing simply needs time to find a way to get the 737MAX aerodynamical neutral
like any airliner in the 21st century should be

So rather than halt production of an a/c that they will have to physically modify, they continue to spit them out at 40+ per month?
If hardware changes are required and Boeing knows it they will look even more foolish for continuing to produce the frames that will not be able to fly.


i have no insider informations

but i think
- in the beginning they had no clue but didnt want to shut down production because they wanted to show that this is only a minor problem
- then they recognised the problem, but wanted to avoid the breakdown of the delivery chain and put off the decision a little more in the hope they can outsmart the regulators with an MCAS 2.0
- as they saw that they could not cheat the regulators (exept the FAA) with the MCAS 2.0 and they insist on a test of the 737MAX in flight, to see the attitudes without the augmentation, to check if it really pitches up in normal operation, they didnt stop production and tried to make the "bill" as high as possible for the US politics to help them out with political power (each more parked 737MAX frame is a huge incentive to US politics to find a way to get the other countrys to accept the 737MAX/MCAS2.0 in service)

it seems like the politic power wasnt made available or it was not strong enough
i would suspect a significant reduce of production in the next weeks (or a significant reinforcement of applicated political power)
Last edited by asdf on Mon Nov 04, 2019 7:18 pm, edited 1 time in total.
 
kayik
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 7:17 pm

Polot wrote:
kayik wrote:
LondonAero wrote:
Can someone send over a link to the comments from IATA / Alexandre de Juniac? Thanks

https://www.scmp.com/news/hong-kong/tra ... summer-air

That is from May 2019. He was talking about summer 2019, not summer 2020.


You are right my apologies. I was reading another article and it was attached to it, I did not notice.
 
Amiga500
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 7:23 pm

LondonAero wrote:
"there has been a lot of work done on the design of the software," Ky said. But he added: "We think there is still some work to be done".

How has Boeing not finished this yet? Is this last bit of work on the software so difficult that maybe it is not solvable?


That is not good news for Boeing.

EASA would appear not to be convinced all is adequately solved. So getting to flight test alone is not Boeing home and dried.

It does as you say, raise the question, "why?", and it would on the surface, imply grim things.
 
asdf
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 7:24 pm

2175301 wrote:
Alfons wrote:
tedzbear wrote:
Why is it taking so long for Boeing to get the software fix ready for certification?


because they want to make it sure that it's also certifiable by regulators which are not bought by them.

.... and one of the things they did was to run a test on what would happen if by chance there were 5 specific radiation induced bit flips in the flight computer. .


no one is expecting 5 bits to flip

as i had understood this whole "bit flip" thing is a more or less abstract probability calculation and its required in the regulations
 
XRAYretired
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 7:27 pm

2175301 wrote:
Alfons wrote:
tedzbear wrote:
Why is it taking so long for Boeing to get the software fix ready for certification?


because they want to make it sure that it's also certifiable by regulators which are not bought by them.


There are two aspects to why the delays: MCAS version 2 was apparently fully tested in June; and had the regulators stopped there it is likely that the 737Max would have likely returned to flight status by the end of August.

However, the regulators were concerned with other things - and one of the things they did was to run a test on what would happen if by chance there were 5 specific radiation induced bit flips in the flight computer. Now the odds of that happening are extreemly remote (and well rarer than any certification standard): I've had it explained that 1 bit flip is clearly possible within the certification standard. 2 might occur. 5 no way.

Based on a statisticaly virtually improbably induced failure in the flight control computer... the regulators then told Boeing that they would have to fix that too....

My understanding is that the real reason for this was by having Boeing update the flight control computer software and operation to closer to modern standards that it would also reduce other issues - and all the direct treaty involved regulator agencies (Brazil, Canada, EASA) felt that was a desirable thing to do. China is not involved in this international agency treaty group; but I understand has been granted observer and comment rights so that they are at least knowledgeable on the intricacies and can provide input (but not demand changes as Brazil, Canada, and EASA can).

Boeing agreed - and it appears at this point that this "upgrade the flight control computer software" has delayed Max reentry by about 6 months (new test flights in November to validate the new flight control computer software). There has been some slippage due to ensuring that Boeing and the treaty country regulator agencies are all on board with the final software's purpose and expected test results.

Based on everything I am hearing - it is indeed likely that the FAA will in fact certify the 737Max with the upgrades developed yet in 2019 (4th quarter).

EASA and the other regulators have always had in their treaties the responsibility to validate any specific features significantly different than FAA standards and to set their own training requirements. EASE has just indicated that they believe it will take them no more than a month after FAA approval (January with a December FAA approval).

Since Brazil, Canada, and EASA regulator agencies have been heavily involved with the FAA and Boeing on the issue, the fix, the standards for return to service... I anticipate no surprises from anyone unless the FAA identifies a new issue that has to be resolved before re-certification. China is unlikely to have any serious issues - as I am sure that they are trying to build good relations with this existing treaty group as they would like to be a member in the future. Of course, each national agency (or EASA for much of Europe) has their own rights and responsibilities in relationship to certifying the 737Max for service in their countries and specifying training requirements. In reality, most of the rest of the world just accepts the certification and training requirements from Brazil, Canada, EASA, and the FAA in the United states.

Have a great day,

Sorry, but the 'bitflip' requirement of 5 bits will have been based upon the probability of the number of bitflips that are predictable in a flight leg profile with a probability equivalent to Hazardous/Catastrophic event. The requirement is to demonstrate that the worst case set of 5 bits will not result in Hazardous/Catastrophic effect. The test failed. The standard requirement in Aerospace IS 'extremely remote likelihood' for catastrophic failures. It is also likely that 5 bits is exactly the same number that was assessed for NG.

No anti-Boeing conspiracy here (nor captured regulator leniency).

Ray
 
oschkosch
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 7:27 pm

BEG2IAH wrote:
HELSINKI (Reuters) - Boeing's <BA.N> grounded 737 MAX airliner is likely to return to service in Europe during the first quarter of 2020, the head of the European Union Aviation Safety Agency (EASA) said on Monday.

While the European regulator expects to give its approval in January, preparations by national authorities and airlines may delay the resumption of commercial flights by up to another two months, EASA executive director Patrick Ky indicated.

Source: https://finance.yahoo.com/news/boeings-grounded-max-seen-resuming-170540590.html


Good to see EASA showing its independence here!
:stirthepot: :airplane: "This airplane is designed by clowns, who in turn are supervised by monkeys" :airplane: :stirthepot:
 
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par13del
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 7:30 pm

asdf wrote:
i have no insider informations

but i think
- in the beginning they had no clue but didnt want to shut down production because they wanted to show that this is only a minor problem
- then they recognised the problem, but wanted to avoid the breakdown of the delivery chain and put off the decision a little more in the hope they can outsmart the regulators with an MCAS 2.0
- as they saw that they could not cheat the regulators (exept the FAA) with the MCAS 2.0 and they insist on a test of the 737MAX in flight, to see the attitudes without the augmentation,

Except based on what has already been made public, it was the regulators who sprung something, namely the Bit Flip issue, so far we have not heard much of anything after the June submission and testing of MCAS 2.0. We also had the list of items that EASA threw up, so I think it is much more than wanting a test flight without MCAS.
My thought is that the only difficult item is the trim wheel, difficult to make it larger at this stage of the game, that would have to go into the production line and retrofitted to existing frames on a schedule.
 
Noshow
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 7:30 pm

kayik wrote:
Noshow wrote:
O'Leary said he is not sure to have any MAX back by summer 2020. That would put the return to service behind Q1 2020. This means behind the timeframe the Boeing CEO has said he would need to halt the MAX-production without renewed permit to fly. Is there something new brewing?


Now, the head of IATA, Alexandre de Juniac, says he does not expect to see the 737 Max back in the skies until August.



This was the claimed IATA statement from above.
 
BEG2IAH
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 7:44 pm

It looks like this is the first semi-positive statement coming from EASA regarding Max. Ky wouldn't mention January 2020 unless he's 99% certain they will approve the changes Boeing made and sent to the FAA. I see this as a very positive development.
Flying at the cruising altitude is (mostly) boring. I wish all flights were nothing but endless take offs and landings every 10 minutes or so.
 
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par13del
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 7:45 pm

XRAYretired wrote:
It is also likely that 5 bits is exactly the same number that was assessed for NG.

No anti-Boeing conspiracy here (nor captured regulator leniency).

Ray

Based on the article in the link below, it appears as if some bit flip tests are specific to the MAX, still searching for whether it was part of the NG certification.
https://www.seattletimes.com/business/b ... -controls/
 
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Revelation
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 7:46 pm

mjoelnir wrote:
When did I ask or comment on the 737NG flying on? I am absolutely not interested what and if something is done with the 737NG. I am just against the silly argument that, because it was this way on the NG, it should be kept on the MAX.

The inverse would be to re-qualify everything from scratch which is something no one suggests, unless they want airliners to cost huge amounts of money

mjoelnir wrote:
You get exited about about the dangers of Lion Air pilots and maintenance, but when it gets to one of the main points that caused this accident, than you go full tilt for doing nothing. I assume because that could inconvenience the blessed mother Boeing.

Actually what I wrote about back porting changes to the NG would be a big inconvenience for the blessed mother Boeing.

Since you mention it, IMO your lack of concern about JT passengers is pretty revealing.

It may well be that there other exemptions for other frames and on the business frames the people who buy them have to judge the risks. But I dare you to show me one frame build today, that gets exactly this exemption from the rules, like the 737 gets.

Of course not, exemptions are considered on a per-model basis.
Wake up to find out that you are the eyes of the world
The heart has its beaches, its homeland and thoughts of its own
Wake now, discover that you are the song that the morning brings
The heart has its seasons, its evenings and songs of its own
 
oschkosch
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 7:51 pm

BEG2IAH wrote:
It looks like this is the first semi-positive statement coming from EASA regarding Max. Ky wouldn't mention January 2020 unless he's 99% certain they will approve the changes Boeing made and sent to the FAA. I see this as a very positive development.
I think its just a statement based on the assumption that all goes well but without going into details. EASA still might not be satisfied and prolong the grounding further.

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XRAYretired
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 8:02 pm

par13del wrote:
XRAYretired wrote:
It is also likely that 5 bits is exactly the same number that was assessed for NG.

No anti-Boeing conspiracy here (nor captured regulator leniency).

Ray

Based on the article in the link below, it appears as if some bit flip tests are specific to the MAX, still searching for whether it was part of the NG certification.
https://www.seattletimes.com/business/b ... -controls/

Of course its is specific to MAX that is what is being assessed. The bits will be selected based upon worst case failure modes and MAX added Hazardous/Catastrophic failure modes that did not exist on NG.

It is entirely possible you will find no NG test per-se, since if no hazardous/catastrophic failure modes existed in the FHA, it would have finished at that point.

PS. A similar situation may also exist for the original MAX.
Ray
 
mjoelnir
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 8:37 pm

Revelation wrote:
mjoelnir wrote:
When did I ask or comment on the 737NG flying on? I am absolutely not interested what and if something is done with the 737NG. I am just against the silly argument that, because it was this way on the NG, it should be kept on the MAX.

The inverse would be to re-qualify everything from scratch which is something no one suggests, unless they want airliners to cost huge amounts of money

We already know that Boeing and the FAA puts cost above safety.

Revelation wrote:
mjoelnir wrote:
You get exited about about the dangers of Lion Air pilots and maintenance, but when it gets to one of the main points that caused this accident, than you go full tilt for doing nothing. I assume because that could inconvenience the blessed mother Boeing.

Actually what I wrote about back porting changes to the NG would be a big inconvenience for the blessed mother Boeing.

Since you mention it, IMO your lack of concern about JT passengers is pretty revealing.


Boeing hardly needs the feeble help of JT to make the 737MAX a deathtrap.

You talk about concerns for JT passengers. I talk about concern for all 737MAX. passengers.

The thinks I talk about are identified as main contributor to the crash.

You want to talk about the peripheral contributor to the crash, to point away from the main points.

Revelation wrote:
It may well be that there other exemptions for other frames and on the business frames the people who buy them have to judge the risks. But I dare you to show me one frame build today, that gets exactly this exemption from the rules, like the 737 gets.

Of course not, exemptions are considered on a per-model basis.


Exactly the MAX is a new model, so it needs the consideration. You just want that people do not check up on exemptions with a new model.
 
MSPNWA
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 8:54 pm

mjoelnir wrote:
We already know that Boeing and the FAA puts cost above safety.


In the past so has JT, Indonesia, ET, Ethiopia, EASA, etc., etc. Your point? What does that have to do with re-qualification?
 
BEG2IAH
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 9:09 pm

MSPNWA wrote:
mjoelnir wrote:
We already know that Boeing and the FAA puts cost above safety.


In the past so has JT, Indonesia, ET, Ethiopia, EASA, etc., etc. Your point? What does that have to do with re-qualification?


When you read some of the posts here you would think this is a website with the biggest fan-base of aviation haters. These two crashes of B737 MAX are not the first ones in aviation history, not the last ones (not speaking of the type, i.e., MAX) and the industry should and will learn from everything that went wrong. I would love to see a discussion of MAX back-to-flight challenges instead of rehashing the same arguments over and over again. The horse has long been dead, stop kicking it. It looks like the FAA and EASA are closer to recertifying the plane than keeping it grounded and that's exciting news at least for me.

Can we talk about Boeing/FAA/EASA test flights that are upcoming?
Flying at the cruising altitude is (mostly) boring. I wish all flights were nothing but endless take offs and landings every 10 minutes or so.
 
morrisond
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 9:14 pm

mjoelnir wrote:
Revelation wrote:
mjoelnir wrote:
When did I ask or comment on the 737NG flying on? I am absolutely not interested what and if something is done with the 737NG. I am just against the silly argument that, because it was this way on the NG, it should be kept on the MAX.

The inverse would be to re-qualify everything from scratch which is something no one suggests, unless they want airliners to cost huge amounts of money

We already know that Boeing and the FAA puts cost above safety.

Revelation wrote:
mjoelnir wrote:
You get exited about about the dangers of Lion Air pilots and maintenance, but when it gets to one of the main points that caused this accident, than you go full tilt for doing nothing. I assume because that could inconvenience the blessed mother Boeing.

Actually what I wrote about back porting changes to the NG would be a big inconvenience for the blessed mother Boeing.

Since you mention it, IMO your lack of concern about JT passengers is pretty revealing.


Boeing hardly needs the feeble help of JT to make the 737MAX a deathtrap.

You talk about concerns for JT passengers. I talk about concern for all 737MAX. passengers.

The thinks I talk about are identified as main contributor to the crash.

You want to talk about the peripheral contributor to the crash, to point away from the main points.

Revelation wrote:
It may well be that there other exemptions for other frames and on the business frames the people who buy them have to judge the risks. But I dare you to show me one frame build today, that gets exactly this exemption from the rules, like the 737 gets.

Of course not, exemptions are considered on a per-model basis.


Exactly the MAX is a new model, so it needs the consideration. You just want that people do not check up on exemptions with a new model.


You could save yourself a lot of typing each time by just typing "Boeing is Evil and deserve to burn, everything else is irrelevant in the Aviation industry and we will never have another crash as long as Boeing is shutdown"
 
shmerik
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 9:24 pm

BEG2IAH wrote:
Can we talk about Boeing/FAA/EASA test flights that are upcoming?


Is there a timeline out for when the flights are to be carried out?

I'm really hoping part of this will include the recommended re-evaluation of the MAX's flight characteristics without MCAS on approach to stall. I'm not able to tell if it sounded like they will actually re-do this in a flight or if they were just suggesting to look at the old test data again but I'm really curious about the extent of the stick lightening that MCAS was meant to resolve.
 
mjoelnir
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Mon Nov 04, 2019 9:24 pm

MSPNWA wrote:
mjoelnir wrote:
We already know that Boeing and the FAA puts cost above safety.


In the past so has JT, Indonesia, ET, Ethiopia, EASA, etc., etc. Your point? What does that have to do with re-qualification?


It would make sense to install EICAS into the MAX. Already done in the P-8 so Boeing has experience with doing that.
It would make sense to fix the manual trim wheel, hardly something that is outside the competence of Boeing.
I can keep on with all the complaints of the various certification authorities that have been here discussed before.

The above will cost money, that is why Boeing is dragging its feet and plays chicken with the regulators, daring them to not certify the bare minimum Boeing is prepared to do.

Please point to where EASA has to your knowledge accepted safety related corner cutting, because it would cost the aircraft producer more money to do it the right way.
Your argument that it is allowed for Boeing to cut corners, because everybody does it, does not hold water.

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