Olddog
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu Jun 13, 2019 6:36 pm

Problem is that AA CEO can't decide when EASA or CAAC will lift the grounding.
When UK was in it wanted a lot of opt-outs, now it is out it wants opt-ins
 
DenverTed
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu Jun 13, 2019 7:14 pm

Revelation wrote:
DenverTed wrote:
Mid March it was flying at the end of May. Mid June it is end of August. Kind of a rolling two month out. Not much new information right? How much more pilot training will be required. Seems like the answer to that question is part of the critical path. Until some answers come out on the fix, it is still a month or two until it's in service. It's been three months and there are no answers yet. The busy summer season is not going to happen. I would place my bets around November 1 at this point.

AA's CEO gave a crisp answer yesterday (flying mid August, first scheduled flight Sept 3rd) that some partisans are rejecting in favor of a click bait out of context article that was based on selectively quoting part of a statement made by a FAA official said to be trustworthy which in turn was based on a statement from the Boeing CEO who is now said to be untrustworthy, and every other Boeing employee is also now said to be untrustworthy as well.

Splitting the baby and going with Nov 1st certainly would pass muster here, I imagine.

I thought WN, UA, and AA have been throwing out dates since this began. What makes this announcement by AA any more definitive? I suppose it is indicative of good information AA has from the FAA. Fine with me, they fixed it which was the main point. But, I thought there was an open question about more training, or simulator training. Has this question been answered as to what will be required?
 
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Revelation
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu Jun 13, 2019 7:17 pm

Olddog wrote:
Problem is that AA CEO can't decide when EASA or CAAC will lift the grounding.

AA's MAXes don't fly to EU or China so it's no big deal to him.
Wake up to find out that you are the eyes of the world
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Wake now, discover that you are the song that the morning brings
The heart has its seasons, its evenings and songs of its own
 
Interested
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu Jun 13, 2019 8:01 pm

Revelation wrote:
DenverTed wrote:
Mid March it was flying at the end of May. Mid June it is end of August. Kind of a rolling two month out. Not much new information right? How much more pilot training will be required. Seems like the answer to that question is part of the critical path. Until some answers come out on the fix, it is still a month or two until it's in service. It's been three months and there are no answers yet. The busy summer season is not going to happen. I would place my bets around November 1 at this point.

AA's CEO gave a crisp answer yesterday (flying mid August, first scheduled flight Sept 3rd) that some partisans are rejecting in favor of a click bait out of context article that was based on selectively quoting part of a statement made by a FAA official said to be trustworthy which in turn was based on a statement from the Boeing CEO who is now said to be untrustworthy, and every other Boeing employee is also now said to be untrustworthy as well.

Splitting the baby and going with Nov 1st certainly would pass muster here, I imagine.


I'm saying the plane won't fly this year

Too many questions, too much scrutiny, too much risk to make hasty decisions

Jobs are on the line now and people can't afford to take any risks at all

As quick as they answer one question another will arise
 
morrisond
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu Jun 13, 2019 8:11 pm

Interested wrote:
Revelation wrote:
DenverTed wrote:
Mid March it was flying at the end of May. Mid June it is end of August. Kind of a rolling two month out. Not much new information right? How much more pilot training will be required. Seems like the answer to that question is part of the critical path. Until some answers come out on the fix, it is still a month or two until it's in service. It's been three months and there are no answers yet. The busy summer season is not going to happen. I would place my bets around November 1 at this point.

AA's CEO gave a crisp answer yesterday (flying mid August, first scheduled flight Sept 3rd) that some partisans are rejecting in favor of a click bait out of context article that was based on selectively quoting part of a statement made by a FAA official said to be trustworthy which in turn was based on a statement from the Boeing CEO who is now said to be untrustworthy, and every other Boeing employee is also now said to be untrustworthy as well.

Splitting the baby and going with Nov 1st certainly would pass muster here, I imagine.


I'm saying the plane won't fly this year

Too many questions, too much scrutiny, too much risk to make hasty decisions

Jobs are on the line now and people can't afford to take any risks at all

As quick as they answer one question another will arise


Is this a Haiku?
 
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Revelation
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu Jun 13, 2019 8:31 pm

DenverTed wrote:
I thought WN, UA, and AA have been throwing out dates since this began. What makes this announcement by AA any more definitive? I suppose it is indicative of good information AA has from the FAA. Fine with me, they fixed it which was the main point. But, I thought there was an open question about more training, or simulator training. Has this question been answered as to what will be required?

Yes, we are in agreement, which is why I used the word crisp as opposed to definitive. It's just a data point, but at least it's an unambiguous data point, made by someone who has a public stature and the need to retain credibility going forward.

Currently I can't read the CNBC transcript link I posted earlier, but IIRC the entire package (software fix, documentation, training material) was submitted and questions keep going back and forth between Boeing and FAA. It seems the next milestone we should see is a joint FAA-Boeing test flight.
Wake up to find out that you are the eyes of the world
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hivue
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu Jun 13, 2019 8:41 pm

There a lot of undelivered MAXs parked at Boeing Field and Everett. Obviously they were not trucked there from Renton. What are the precise circumstances under which the FAA allows MAXs to be flown (aside from test/certification flights)? Can Boeing move undelivered frames out of Washington state for storage (Victorville, Tucson,...)? Could they be delivered to airlines and the airlines would then store them (not that any airline would agree to do that).
"You're sitting. In a chair. In the SKY!!" ~ Louis C.K.
 
planecane
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu Jun 13, 2019 8:46 pm

Interested wrote:
Revelation wrote:
DenverTed wrote:
Mid March it was flying at the end of May. Mid June it is end of August. Kind of a rolling two month out. Not much new information right? How much more pilot training will be required. Seems like the answer to that question is part of the critical path. Until some answers come out on the fix, it is still a month or two until it's in service. It's been three months and there are no answers yet. The busy summer season is not going to happen. I would place my bets around November 1 at this point.

AA's CEO gave a crisp answer yesterday (flying mid August, first scheduled flight Sept 3rd) that some partisans are rejecting in favor of a click bait out of context article that was based on selectively quoting part of a statement made by a FAA official said to be trustworthy which in turn was based on a statement from the Boeing CEO who is now said to be untrustworthy, and every other Boeing employee is also now said to be untrustworthy as well.

Splitting the baby and going with Nov 1st certainly would pass muster here, I imagine.


I'm saying the plane won't fly this year

Too many questions, too much scrutiny, too much risk to make hasty decisions

Jobs are on the line now and people can't afford to take any risks at all

As quick as they answer one question another will arise


Hasty decisions? It's been grounded for 3 months already and all indications are it will remain so for at least another 1 or 2 months. The 787 was only grounded for 3 months to redesign the battery and container for it for a battery type that was never used on a commercial aircraft previously.

Experts are not like a.net forum members that keep coming up with new questions every day. They will have come up with a set of questions one time and the follow ups will only be when they don't uderstand or don't like the answer. They are not going back to Boeing every other day and saying, "we just thought of something else..."
 
planecane
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu Jun 13, 2019 8:49 pm

hivue wrote:
There a lot of undelivered MAXs parked at Boeing Field and Everett. Obviously they were not trucked there from Renton. What are the precise circumstances under which the FAA allows MAXs to be flown (aside from test/certification flights)? Can Boeing move undelivered frames out of Washington state for storage (Victorville, Tucson,...)? Could they be delivered to airlines and the airlines would then store them (not that any airline would agree to do that).


I'm pretty sure they just classify them all as test flights and get a waiver. Even if they don't have the new software on board, I'm very confident that a Boeing pilot ferrying a MAX will know exactly what to do if MCAS goes berserk so there isn't any risk to allowing these flights.
 
smartplane
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu Jun 13, 2019 8:50 pm

hivue wrote:
There a lot of undelivered MAXs parked at Boeing Field and Everett. Obviously they were not trucked there from Renton. What are the precise circumstances under which the FAA allows MAXs to be flown (aside from test/certification flights)? Can Boeing move undelivered frames out of Washington state for storage (Victorville, Tucson,...)? Could they be delivered to airlines and the airlines would then store them (not that any airline would agree to do that).

When an aircraft model is grounded, it loses it's hull & flying insurance - ground cover only.

Presumably, Boeing are delivering frames to storage facilities under experimental / test cover, with test crew (probably a record number of test crew at work). Interesting to know if FAA consent to permit this, has been influenced politically.

Strategically, if Boeing are required to update software, and other elements of the aircraft, keeping undelivered aircraft close, will speed the process.

There is also an issue with technical delivery. Would a customer want to take delivery, as this is a significant financial and insurance milestone? Let Boeing manage the storage, funding and insurance.
 
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Revelation
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu Jun 13, 2019 9:06 pm

smartplane wrote:
Presumably, Boeing are delivering frames to storage facilities under experimental / test cover, with test crew (probably a record number of test crew at work).

We were told Boeing preferred to move 787 flight test and delivery to KCHS to make more room at KPAE for 737s.

Maybe they also felt they needed to reduce the workload on their 737 pilots by doing so.
Wake up to find out that you are the eyes of the world
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aerolimani
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu Jun 13, 2019 9:13 pm

A.net needs a betting board. We can all place bets on what dates the FAA ungrounding and first commercial flight will happen. The only question is what the prizes should be.
 
BravoOne
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu Jun 13, 2019 9:27 pm

Maybe I missed it earlier in a previous post, but Boeing announced that they were going to start using Kelly AFB for future storage.
Last edited by BravoOne on Thu Jun 13, 2019 9:38 pm, edited 1 time in total.
 
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ACCS300
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu Jun 13, 2019 9:29 pm

Interested wrote:
Revelation wrote:
DenverTed wrote:
Mid March it was flying at the end of May. Mid June it is end of August. Kind of a rolling two month out. Not much new information right? How much more pilot training will be required. Seems like the answer to that question is part of the critical path. Until some answers come out on the fix, it is still a month or two until it's in service. It's been three months and there are no answers yet. The busy summer season is not going to happen. I would place my bets around November 1 at this point.

AA's CEO gave a crisp answer yesterday (flying mid August, first scheduled flight Sept 3rd) that some partisans are rejecting in favor of a click bait out of context article that was based on selectively quoting part of a statement made by a FAA official said to be trustworthy which in turn was based on a statement from the Boeing CEO who is now said to be untrustworthy, and every other Boeing employee is also now said to be untrustworthy as well.

Splitting the baby and going with Nov 1st certainly would pass muster here, I imagine.


I'm saying the plane won't fly this year

Too many questions, too much scrutiny, too much risk to make hasty decisions

Jobs are on the line now and people can't afford to take any risks at all

As quick as they answer one question another will arise


I'm beginning to get that feeling too, especially with Ralph Nader's statements last week. I have a funny feeling it will never fly again, we've never been through anything similar in recent years so nothing to compare it to. My guess is a major re-design, re-certification and a new-name at minimum. I'm sure many close to Boeing fear that with 1000s of these MAXs in the air a few years from time, the likelihood of another catastrophe, perhaps, increases.
 
ArgentoSystems
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu Jun 13, 2019 9:38 pm

aerolimani wrote:
A.net needs a betting board. We can all place bets on what dates the FAA ungrounding and first commercial flight will happen. The only question is what the prizes should be.

You can bet now on stock market. I forecast BA to decline $10/month and trade accordingly.
 
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7BOEING7
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu Jun 13, 2019 9:49 pm

hivue wrote:
There a lot of undelivered MAXs parked at Boeing Field and Everett. Obviously they were not trucked there from Renton. What are the precise circumstances under which the FAA allows MAXs to be flown (aside from test/certification flights)? Can Boeing move undelivered frames out of Washington state for storage (Victorville, Tucson,...)? Could they be delivered to airlines and the airlines would then store them (not that any airline would agree to do that).


Boeing is probably flying the MAX's under the production ticket as far as flights between Renton, Boeing Field, Paine Field and any other "local " airports (MWH, GEG, YKM, etc) doing production acceptance flights. Ferry permits may be required for flights to places like San Antonio however.

Since the MAX's are not in "delivery" configuration (MCAS is not recertified yet) they cannot be "bought" FAA, so they cannot be delivered to the customer.

smartplane wrote:
Presumably, Boeing are delivering frames to storage facilities under experimental / test cover, with test crew (probably a record number of test crew at work). Interesting to know if FAA consent to permit this, has been influenced politically.


Since Boeing is building fewer 737's per month than a year ago they haven't had to add any addition pilots and the ones they have are all qualified to do the job -- no special requirements. There are already procedures in place to move airplanes that don't have a standard airworthiness certificate so no political influence is required.
 
smartplane
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu Jun 13, 2019 9:57 pm

7BOEING7 wrote:
There are already procedures in place to move airplanes that don't have a standard airworthiness certificate so no political influence is required.

But this isn't a non-standard airworthiness certificate. This is a suspended / rescinded airworthiness certificate. And it's the OEM's decision to continue manufacturing.
 
PlanesNTrains
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu Jun 13, 2019 10:02 pm

ACCS300 wrote:
Interested wrote:
Revelation wrote:
AA's CEO gave a crisp answer yesterday (flying mid August, first scheduled flight Sept 3rd) that some partisans are rejecting in favor of a click bait out of context article that was based on selectively quoting part of a statement made by a FAA official said to be trustworthy which in turn was based on a statement from the Boeing CEO who is now said to be untrustworthy, and every other Boeing employee is also now said to be untrustworthy as well.

Splitting the baby and going with Nov 1st certainly would pass muster here, I imagine.


I'm saying the plane won't fly this year

Too many questions, too much scrutiny, too much risk to make hasty decisions

Jobs are on the line now and people can't afford to take any risks at all

As quick as they answer one question another will arise


I'm beginning to get that feeling too, especially with Ralph Nader's statements last week. I have a funny feeling it will never fly again, we've never been through anything similar in recent years so nothing to compare it to. My guess is a major re-design, re-certification and a new-name at minimum. I'm sure many close to Boeing fear that with 1000s of these MAXs in the air a few years from time, the likelihood of another catastrophe, perhaps, increases.


I haven't followed developments much over the past month or so, but can you clarify what is so egregiously defective with the MAX that it would never fly again? Honestly curious.
-Dave


MAX’d out on MAX threads. If you are starting a thread, and it’s about the MAX - stop. There’s already a thread that covers it.
 
planecane
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu Jun 13, 2019 10:36 pm

smartplane wrote:
7BOEING7 wrote:
There are already procedures in place to move airplanes that don't have a standard airworthiness certificate so no political influence is required.

But this isn't a non-standard airworthiness certificate. This is a suspended / rescinded airworthiness certificate.


I don't think that is technically correct. I think the model still has an airworthiness certificate. The FAA has just prohibited the operation of the aircraft.
 
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PixelFlight
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu Jun 13, 2019 11:13 pm

planecane wrote:
smartplane wrote:
7BOEING7 wrote:
There are already procedures in place to move airplanes that don't have a standard airworthiness certificate so no political influence is required.

But this isn't a non-standard airworthiness certificate. This is a suspended / rescinded airworthiness certificate.


I don't think that is technically correct. I think the model still has an airworthiness certificate. The FAA has just prohibited the operation of the aircraft.

The 737-8 is included in the Type Certificate Data Sheet A16WE Revision Number 64.
http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgMakeModel.nsf/0/A2C69E2A4D5ED6788625832A006B30E1?OpenDocument
http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgMakeModel.nsf/0/179CDACD213801658625832A006B2E37?OpenDocument

This EOP document prohibit the 737-8/9:
https://www.faa.gov/news/updates/media/can-2019-05.pdf
the FAA issued an Emergency Order of Prohibition that prohibits the operation of Boeing Model 737-8 and 737-9 airplanes by U.S.-certificated operators or in U.S. territory.
 
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7BOEING7
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Thu Jun 13, 2019 11:19 pm

planecane wrote:
smartplane wrote:
7BOEING7 wrote:
There are already procedures in place to move airplanes that don't have a standard airworthiness certificate so no political influence is required.

But this isn't a non-standard airworthiness certificate. This is a suspended / rescinded airworthiness certificate.


I don't think that is technically correct. I think the model still has an airworthiness certificate. The FAA has just prohibited the operation of the aircraft.


:checkmark: :checkmark:

Do you want to add "for commercial use"?

See attached discussion of Special Flight Permits

https://www.faa.gov/about/office_org/fi ... permit.pdf
 
Chemist
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri Jun 14, 2019 12:24 am

morrisond wrote:
Interested wrote:
Revelation wrote:
AA's CEO gave a crisp answer yesterday (flying mid August, first scheduled flight Sept 3rd) that some partisans are rejecting in favor of a click bait out of context article that was based on selectively quoting part of a statement made by a FAA official said to be trustworthy which in turn was based on a statement from the Boeing CEO who is now said to be untrustworthy, and every other Boeing employee is also now said to be untrustworthy as well.

Splitting the baby and going with Nov 1st certainly would pass muster here, I imagine.


I'm saying the plane won't fly this year

Too many questions, too much scrutiny, too much risk to make hasty decisions

Jobs are on the line now and people can't afford to take any risks at all

As quick as they answer one question another will arise


Is this a Haiku?


When I learned to write in school, I was told paragraphs can contain more than one sentence.
 
ArgentoSystems
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri Jun 14, 2019 1:41 am

PlanesNTrains wrote:
I haven't followed developments much over the past month or so, but can you clarify what is so egregiously defective with the MAX that it would never fly again? Honestly curious.

When people say 'never' it rather means few years. MAXes will eventually fly, possibly after extensive, expensive, and time consuming rework.
I find the MCAS thing conceptually flawed. It is needed for stall protection in normal mode, but at the same time it relies on sensors prone to failure and so it does not have very high up-time.

If you want a car analogy, would you like to drive a car where airbag has 95% uptime? Sure you almost never need it, but when you do, it better be 100% ready. MCAS is supposedly designed for similarly rare events but just does not have reliability.
Last edited by ArgentoSystems on Fri Jun 14, 2019 1:45 am, edited 1 time in total.
 
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aerolimani
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri Jun 14, 2019 1:42 am

Chemist wrote:
morrisond wrote:
Interested wrote:

I'm saying the plane won't fly this year

Too many questions, too much scrutiny, too much risk to make hasty decisions

Jobs are on the line now and people can't afford to take any risks at all

As quick as they answer one question another will arise


Is this a Haiku?

When I learned to write in school, I was told paragraphs can contain more than one sentence.

Come on, people. Let’s try and stay above making personal attacks.

Stay on topic.
 
planecane
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri Jun 14, 2019 2:17 am

ArgentoSystems wrote:
PlanesNTrains wrote:
I haven't followed developments much over the past month or so, but can you clarify what is so egregiously defective with the MAX that it would never fly again? Honestly curious.

When people say 'never' it rather means few years. MAXes will eventually fly, possibly after extensive, expensive, and time consuming rework.
I find the MCAS thing conceptually flawed. It is needed for stall protection in normal mode, but at the same time it relies on sensors prone to failure and so it does not have very high up-time.

If you want a car analogy, would you like to drive a car where airbag has 95% uptime? Sure you almost never need it, but when you do, it better be 100% ready. MCAS is supposedly designed for similarly rare events but just does not have reliability.


Please stop with this nonsense. There is no indication that any civil aviation authority is planning to require an extensive redesign. The two issues causing the delay seem to be figuring out what additional pilot training is needed after the software update and looking at the certification process of the MAX to make sure no other things slipped through the process like MCAS did.

Your analogy to airbags is ok for the original iteration of MCAS although MCAS didn't fail close to 5% of the time (more along the lines of 0.005%). However, the update will prevent a repeat of a runaway stabilizer that can't be counteracted with the control column.
 
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7BOEING7
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri Jun 14, 2019 2:32 am

Revelation wrote:

Currently I can't read the CNBC transcript link I posted earlier, but IIRC the entire package (software fix, documentation, training material) was submitted and questions keep going back and forth between Boeing and FAA. It seems the next milestone we should see is a joint FAA-Boeing test flight.


Boeing has been working with the FAA for months so when they say that he entire package was presented to the FAA, IMHO the back & forth is for the most part not going back & forth anymore and the FAA flight test has been completed. The FAA flight test would normally be part of the "package". Just because Boeing and/or the FAA hasn't announced it to the world doesn't mean it hasn't already occurred.
 
ArgentoSystems
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri Jun 14, 2019 2:37 am

planecane wrote:
There is no indication that any civil aviation authority is planning to require an extensive redesign.

There is no indication otherwise, either.
The two issues causing the delay seem to be figuring out what additional pilot training is needed after the software update and looking at the certification process of the MAX to make sure no other things slipped through the process like MCAS did.

Conjecture.
Your analogy to airbags is ok for the original iteration of MCAS although MCAS didn't fail close to 5% of the time (more along the lines of 0.005%).

You fail to even understand that my analogy can only refer to MCAS 2.0 because failed airbag can never put car in danger. Which by the way, MCAS 2.0 can still do, should two AOA freeze in the same position. However unlikely, that has happened in the past.
 
planecane
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri Jun 14, 2019 2:48 am

ArgentoSystems wrote:
planecane wrote:
There is no indication that any civil aviation authority is planning to require an extensive redesign.

There is no indication otherwise, either.
The two issues causing the delay seem to be figuring out what additional pilot training is needed after the software update and looking at the certification process of the MAX to make sure no other things slipped through the process like MCAS did.

Conjecture.
Your analogy to airbags is ok for the original iteration of MCAS although MCAS didn't fail close to 5% of the time (more along the lines of 0.005%).

You fail to even understand that my analogy can only refer to MCAS 2.0 because failed airbag can never put car in danger. Which by the way, MCAS 2.0 can still do, should two AOA freeze in the same position. However unlikely, that has happened in the past.


You don't understand the changes in MCAS 2.0. Even if both AoA sensors fail in the same position, they'd both have to be past the trigger point. Even if it happens, any counter trim input by the pilot will stop MCAS, MCAS will be limited to one cycle AND it will be limited so that the max trim it commands will still allow pulling back on the control column to keep the aircraft level. So, no, your analogy doesn't work for MCAS 2.0.

As to your other speculation, there are indications in reporting that the MAX will be ungrounded sometime within at most 6 months. If Boeing was getting feedback from regulators that they will require a major redesign and Boeing is hiding that info from shareholders they would be violating all kinds of SEC regulations.
 
ArgentoSystems
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri Jun 14, 2019 2:58 am

planecane wrote:
You don't understand the changes in MCAS 2.0. Even if both AoA sensors fail in the same position, they'd both have to be past the trigger point. Even if it happens, any counter trim input by the pilot will stop MCAS, MCAS will be limited to one cycle AND it will be limited so that the max trim it commands will still allow pulling back on the control column to keep the aircraft level. So, no, your analogy doesn't work for MCAS 2.0.
Thank you. I understand it now completly. Which is exactly how I understood it a month ago.

As to your other speculation, there are indications in reporting that the MAX will be ungrounded sometime within at most 6 months. If Boeing was getting feedback from regulators that they will require a major redesign and Boeing is hiding that info from shareholders they would be violating all kinds of SEC regulations.

And maybe they did violate all kinds of SEC regulations. I mean, they are being investigated. By SEC.
https://www.bloomberg.com/news/articles ... x-troubles
 
aa87
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri Jun 14, 2019 3:18 am

As soon as FAA grounded I predicted that getting fully past this for Boeing (meaning full return of MAX to service and no pax perception issues) will be 2-3 years and $5 billion. Not that MAX will be grounded for 2 years, but that is my prediction on timeframe before BA fully returns to some state of normalcy.
 
h1fl1er
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri Jun 14, 2019 3:55 am

the airlines need this ungrounded. this isn't about just boineg. they have 5000 orders. European airlines too. expecting to make money.

it will be ungrounded in a few months. there wasn't anything that wrong with it.

I mean, boeing haters, as there is a love for wild speculation and what ifs, what if someone wrote in code to the flight control system if random(10000)=1 then crash plane. I mean it's a software flaw. that's what happened here. mcas isn't needed for all but an edge case for this plane, a manual flight at high aoa. it's really something that was never intended to be active. bad software and dependence on a faulty sensor caused it to be. but it is still a software flaw expected to be active in a tiny corner of the flight envelope

extra scrutiny is just to make sure there aren't any other crash plane routines in the software

for the life of me I don't understand why people keep thinking there is something lurking out there wrong with this plane other than they *hope* there is. ffs, they just put some bigger engines on the thing...
 
IADFCO
Posts: 117
Joined: Sun May 22, 2016 4:20 pm

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri Jun 14, 2019 4:36 am

h1fl1er wrote:
the airlines need this ungrounded. this isn't about just boineg. they have 5000 orders. European airlines too. expecting to make money.

it will be ungrounded in a few months. there wasn't anything that wrong with it.

I mean, boeing haters, as there is a love for wild speculation and what ifs, what if someone wrote in code to the flight control system if random(10000)=1 then crash plane. I mean it's a software flaw. that's what happened here. mcas isn't needed for all but an edge case for this plane, a manual flight at high aoa. it's really something that was never intended to be active. bad software and dependence on a faulty sensor caused it to be. but it is still a software flaw expected to be active in a tiny corner of the flight envelope

extra scrutiny is just to make sure there aren't any other crash plane routines in the software

for the life of me I don't understand why people keep thinking there is something lurking out there wrong with this plane other than they *hope* there is. ffs, they just put some bigger engines on the thing...


One reason is that there are very few facts about the key issues concerning the MAX (outside Boeing, that is), so it may be just an easily fixable software flaw and it may be something much more serious that the software tried to hide.

Now that apparently MCAS will activate only once when some AoA threshold is crossed, and will stay inactive until the AoA goes back to below that threshold, means that there are circumstances where one would need MCAS and it is not available. Manual flight at high AoA may be "an edge case", but I (stability & control engineer, not pilot) can think of at least one plausible situation where that can happen. Think a sudden avoidance maneuver that looks like a tight windup turn. What happens then? Maybe a stall that is hard to recover from, maybe not much. We don't know.

[I hate to beat a dead horse, as I have brought up this issue a couple of times before, but I think it's important enough that once every 10**3 postings is an acceptable rate for this thread.]
 
FluidFlow
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri Jun 14, 2019 5:34 am

h1fl1er wrote:
ffs, they just put some bigger engines on the thing...


If it would be that easy to just but some bigger engines on an aircraft, i wonder why it took A&B years and a lot of money to develop the MAX and the NEO. I am sorry but it is a rather complex thing to change something so significant as the engines.

In the case of the MAX it also seems that it was not done properly, otherwise there would be no grounding. Of course it can also be fixed and in a few years we will be here discussing what the actual costs were of the whole project of "just putting some bigger engines on the thing".
 
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PixelFlight
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri Jun 14, 2019 9:32 am

h1fl1er wrote:
I mean, boeing haters, as there is a love for wild speculation and what ifs, what if someone wrote in code to the flight control system if random(10000)=1 then crash plane. I mean it's a software flaw. that's what happened here. mcas isn't needed for all but an edge case for this plane, a manual flight at high aoa. it's really something that was never intended to be active. bad software and dependence on a faulty sensor caused it to be. but it is still a software flaw expected to be active in a tiny corner of the flight envelope

extra scrutiny is just to make sure there aren't any other crash plane routines in the software

With far less speculation, it's more likely that the MCAS v1 software was very well written to comply to his specifications and requirements. To date, I haven't read anything about the MCAS v1 implementation not in compliance with his design. The software flaw in this case is more likely a design flaw due to a missing safety assessment.
 
XRAYretired
Posts: 483
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri Jun 14, 2019 9:43 am

PixelFlight wrote:
h1fl1er wrote:
I mean, boeing haters, as there is a love for wild speculation and what ifs, what if someone wrote in code to the flight control system if random(10000)=1 then crash plane. I mean it's a software flaw. that's what happened here. mcas isn't needed for all but an edge case for this plane, a manual flight at high aoa. it's really something that was never intended to be active. bad software and dependence on a faulty sensor caused it to be. but it is still a software flaw expected to be active in a tiny corner of the flight envelope

extra scrutiny is just to make sure there aren't any other crash plane routines in the software

With far less speculation, it's more likely that the MCAS v1 software was very well written to comply to his specifications and requirements. To date, I haven't read anything about the MCAS v1 implementation not in compliance with his design. The software flaw in this case is more likely a design flaw due to a missing safety assessment.

:checkmark:
Incompetent System Design and validation.

Ray
 
planecane
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri Jun 14, 2019 10:08 am

PixelFlight wrote:
h1fl1er wrote:
I mean, boeing haters, as there is a love for wild speculation and what ifs, what if someone wrote in code to the flight control system if random(10000)=1 then crash plane. I mean it's a software flaw. that's what happened here. mcas isn't needed for all but an edge case for this plane, a manual flight at high aoa. it's really something that was never intended to be active. bad software and dependence on a faulty sensor caused it to be. but it is still a software flaw expected to be active in a tiny corner of the flight envelope

extra scrutiny is just to make sure there aren't any other crash plane routines in the software

With far less speculation, it's more likely that the MCAS v1 software was very well written to comply to his specifications and requirements. To date, I haven't read anything about the MCAS v1 implementation not in compliance with his design. The software flaw in this case is more likely a design flaw due to a missing safety assessment.


I certainly agree with you there. The issue wasn't a "software bug" related to poor coding, it was a logic flaw in the system specifications. A "bug" would have been if it was supposed to use both AoA sensors and a mistake in coding only had it use one.
 
planecane
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri Jun 14, 2019 10:31 am

IADFCO wrote:
h1fl1er wrote:
the airlines need this ungrounded. this isn't about just boineg. they have 5000 orders. European airlines too. expecting to make money.

it will be ungrounded in a few months. there wasn't anything that wrong with it.

I mean, boeing haters, as there is a love for wild speculation and what ifs, what if someone wrote in code to the flight control system if random(10000)=1 then crash plane. I mean it's a software flaw. that's what happened here. mcas isn't needed for all but an edge case for this plane, a manual flight at high aoa. it's really something that was never intended to be active. bad software and dependence on a faulty sensor caused it to be. but it is still a software flaw expected to be active in a tiny corner of the flight envelope

extra scrutiny is just to make sure there aren't any other crash plane routines in the software

for the life of me I don't understand why people keep thinking there is something lurking out there wrong with this plane other than they *hope* there is. ffs, they just put some bigger engines on the thing...


One reason is that there are very few facts about the key issues concerning the MAX (outside Boeing, that is), so it may be just an easily fixable software flaw and it may be something much more serious that the software tried to hide.

Now that apparently MCAS will activate only once when some AoA threshold is crossed, and will stay inactive until the AoA goes back to below that threshold, means that there are circumstances where one would need MCAS and it is not available. Manual flight at high AoA may be "an edge case", but I (stability & control engineer, not pilot) can think of at least one plausible situation where that can happen. Think a sudden avoidance maneuver that looks like a tight windup turn. What happens then? Maybe a stall that is hard to recover from, maybe not much. We don't know.

[I hate to beat a dead horse, as I have brought up this issue a couple of times before, but I think it's important enough that once every 10**3 postings is an acceptable rate for this thread.]


Your issue is not a "real" issue, assuming a proper design. The AoA threshold is based on entering the state during an approach to stall where the stick force gradient reduces. If the pilots are that incompetent that they don't take action to get out of that spot, no software or aircraft design is going to save them. A single "event" that turns into multiple needs for MCAS activation will only happen if the pilots don't take action to get away from stall attitude.

The only times one would possibly need MCAS and not have it available is either:

1) There is an AoA disagree that disables the system. This will now have a warning message and some NNC procedure to follow.

2) Both AoA sensors fail within 5 degrees of each other and both higher thant he MCAS trigger angle for that airspeed. This will cause the pilots to counteract the erroneous single cycle of MCAS with manual electric trim which will disable MCAS from that point forward. There should be a NNC for this situation and I'd imagine part of the required training will be to recognize that MCAS failed and you (the pilot) have now disabled it.

3) Both AoA sensors fail within 5 degrees of each other below the angle for MCAS activation. Therefore it won't activate even if needed. This will be the most difficult to recognize if the AoA display is not standard. With the display, the pilots would notice that the AoA reading never changes.

It's difficult to estimate the rate of dual AoA sensor failure on a 737. I don't know if the incidents would have been reported to the FAA on the NG or earlier or if it was just a maintenance issue. We know there were 3 failures for sure on the MAX. Southwest had performed 41,000 flights and had roughly 10% of the MAXs in service. Therefore there were probably at least 300,000 flights of the MAX. If we quadrouple the known failures to account for failures at a non-MCAS triggering angle as well as the non active side failing that would be 12 failures. That would translate to 1 failure in 25,000 flights. Therefore, a simultaneous failure from independent causes would be expected 1 in 625,000,000 flights. I don't think the entire MAX fleet for the entire service life would even come close to that many flights so, statistically, it should basically never happen. Then, on that 1 flight in 625 million you would also have to have the crew get into the situation where MCAS is needed to possibly have an issue.
 
RickNRoll
Posts: 1710
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri Jun 14, 2019 10:46 am

h1fl1er wrote:
the airlines need this ungrounded. this isn't about just boineg. they have 5000 orders. European airlines too. expecting to make money.

it will be ungrounded in a few months. there wasn't anything that wrong with it.

I mean, boeing haters, as there is a love for wild speculation and what ifs, what if someone wrote in code to the flight control system if random(10000)=1 then crash plane. I mean it's a software flaw. that's what happened here. mcas isn't needed for all but an edge case for this plane, a manual flight at high aoa. it's really something that was never intended to be active. bad software and dependence on a faulty sensor caused it to be. but it is still a software flaw expected to be active in a tiny corner of the flight envelope

extra scrutiny is just to make sure there aren't any other crash plane routines in the software

for the life of me I don't understand why people keep thinking there is something lurking out there wrong with this plane other than they *hope* there is. ffs, they just put some bigger engines on the thing...


Standard testing should have picked up the errors in MCAS. That it wasn't points to a bigger problem in Boeing. Their QA systems also failed. As reported in earlier links, the left hand didn't know what the right hand was doing. That comes down to the management and governance of Boeing. There is also much debate going on about if it was only going to be active in a tiny corner of the flight envelope. The original design had that idea. What was produced was very different and may well have been necessary as anti-stall protection.
 
kalvado
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri Jun 14, 2019 11:18 am

planecane wrote:
The only times one would possibly need MCAS and not have it available is either:

1) There is an AoA disagree that disables the system. This will now have a warning message and some NNC procedure to follow.

Not so fast. AoA failure and MCAS disabling are a relatively frequent scenario to require double failure analysis.
So, you need to consider, for example, what happens if AoA sensor is of -> MCAS off, airspeed unreliable, possibly altitude unreliable AND there is another moderate probability failure, e.g. engine out. How would lack of envelope protection play out in this example?
 
ArgentoSystems
Posts: 294
Joined: Sun Mar 24, 2019 12:05 am

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri Jun 14, 2019 11:26 am

don't forget that they are looking at emergency procedures inherited from NG. Yes, the R-word.
 
Asiaflyer
Posts: 847
Joined: Fri May 11, 2007 11:50 am

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri Jun 14, 2019 11:27 am

h1fl1er wrote:
the airlines need this ungrounded. this isn't about just boineg. they have 5000 orders. European airlines too. expecting to make money.

it will be ungrounded in a few months. there wasn't anything that wrong with it.

I mean, boeing haters, as there is a love for wild speculation and what ifs, what if someone wrote in code to the flight control system if random(10000)=1 then crash plane. I mean it's a software flaw. that's what happened here. mcas isn't needed for all but an edge case for this plane, a manual flight at high aoa. it's really something that was never intended to be active. bad software and dependence on a faulty sensor caused it to be. but it is still a software flaw expected to be active in a tiny corner of the flight envelope

extra scrutiny is just to make sure there aren't any other crash plane routines in the software

for the life of me I don't understand why people keep thinking there is something lurking out there wrong with this plane other than they *hope* there is. ffs, they just put some bigger engines on the thing...

OMG!! Are we back on this level again??
Please read the previous 50 pages of this thread and get an idea of whats actually happening...
SQ,MI,MH,CX,KA,CA,CZ,MU,KE,OZ,QF,NZ,FD,JQ,3K,5J,IT,AI,IC,QR,SK,LF,KL,AF,LH,LX,OS,SR,BA,SN,FR,WF,1I,5T,VZ,VX,AC,NW,UA,US,
 
ltbewr
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri Jun 14, 2019 11:31 am

When the 737MAX can be put back into commercial service and production is very much an wild guessestimate at this time. We do know AA, WN have set schedules without 737MAX's until early September. Perhaps the Paris Air Show will have Boeing make announcements of a tentative schedule for RTS for the 737MAX. That schedule can be possibly longer due to a variety of factors. Making sure the 'cure' isn't worse that the initial 'disease', that is not creating unintended other problems. The corrections on planes in service may be time consuming. Training will have to be more extensive and slow to roll out. There are competing pressures from and upon many parties including Boeing, insurers, airlines, politicians, trade balance, non-US regulators and consumers. The FAA may become a victim again of internal USA politics, like late 2018 and early 2019, with a possible Federal Government shutdown in October due to battles over the budget, the President and our political infighting.

My best guess is that most 737MAX's grounded and in production won't be back to full operation until late December 2019 or early January 2020 and that's if all goes good.
 
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PixelFlight
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri Jun 14, 2019 11:41 am

kalvado wrote:
planecane wrote:
The only times one would possibly need MCAS and not have it available is either:

1) There is an AoA disagree that disables the system. This will now have a warning message and some NNC procedure to follow.

Not so fast. AoA failure and MCAS disabling are a relatively frequent scenario to require double failure analysis.
So, you need to consider, for example, what happens if AoA sensor is of -> MCAS off, airspeed unreliable, possibly altitude unreliable AND there is another moderate probability failure, e.g. engine out. How would lack of envelope protection play out in this example?

Yes, this quickly become a very complex task to analyse any possibilities that brings multiples discrete commands. This situation illustrate how much the 737-8/9 is pushing the pre-FBW design to the limit of the established safety analysis. Not that it's impossible to do, but it's increasingly complex to analyse as discrete automation is added. FBW design are more easy to analyse and to understand as there only a few laws to learn. Still, FBW is not enough to magically overcome sensors failures as the history has show. I highly hope that the civil aircraft industry will work more on sensors prediction and validation algorithm.
 
planecane
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri Jun 14, 2019 12:14 pm

kalvado wrote:
planecane wrote:
The only times one would possibly need MCAS and not have it available is either:

1) There is an AoA disagree that disables the system. This will now have a warning message and some NNC procedure to follow.

Not so fast. AoA failure and MCAS disabling are a relatively frequent scenario to require double failure analysis.
So, you need to consider, for example, what happens if AoA sensor is of -> MCAS off, airspeed unreliable, possibly altitude unreliable AND there is another moderate probability failure, e.g. engine out. How would lack of envelope protection play out in this example?


I don't disagree and that is why procedures and training must be developed to deal with the situation. The MCAS off NNC could be something as simple as slow to flaps 1 speed and set flaps 1 and divert to nearest airport. MCAS seems to have been determined not to be needed with flaps deployed since it was designed not to activate.

It would seem that the most likely time for an AoA sensor failure would be soon after takeoff. Either it will have been damaged on the ground, from FOD or a bird strike. I don't foresee a very high failure rate where suddenly a sensor goes whacko during cruise.

If I was in charge of Boeing, I would do what it takes to get the MAX back in the air now with MCAS 2.0 and procedures that will minimize the likelihood of a dangerous situation. Then, I would design the addition of a 3rd (or 3rd and 4th) AoA sensor to make a truly robust system with voting and prediction capability for a truly robust system and roll it into production and begin a retrofit program.

They could add a standalone AoA processor that takes the 4 inputs, processes them and outputs the result to the FCC using the current inputs. The FCC wouldn't need to be modified. The "AoA processor" could intentionally feed divergent results if it is unable to determine the AoA with enough reliability. Then, based on MCAS 2.0, the FCC would just disable MCAS and display an AoA disagree warning.
 
kalvado
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri Jun 14, 2019 12:17 pm

planecane wrote:
kalvado wrote:
planecane wrote:
The only times one would possibly need MCAS and not have it available is either:

1) There is an AoA disagree that disables the system. This will now have a warning message and some NNC procedure to follow.

Not so fast. AoA failure and MCAS disabling are a relatively frequent scenario to require double failure analysis.
So, you need to consider, for example, what happens if AoA sensor is of -> MCAS off, airspeed unreliable, possibly altitude unreliable AND there is another moderate probability failure, e.g. engine out. How would lack of envelope protection play out in this example?


I don't disagree and that is why procedures and training must be developed to deal with the situation. The MCAS off NNC could be something as simple as slow to flaps 1 speed and set flaps 1 and divert to nearest airport. MCAS seems to have been determined not to be needed with flaps deployed since it was designed not to activate.

It would seem that the most likely time for an AoA sensor failure would be soon after takeoff. Either it will have been damaged on the ground, from FOD or a bird strike. I don't foresee a very high failure rate where suddenly a sensor goes whacko during cruise.

If I was in charge of Boeing, I would do what it takes to get the MAX back in the air now with MCAS 2.0 and procedures that will minimize the likelihood of a dangerous situation. Then, I would design the addition of a 3rd (or 3rd and 4th) AoA sensor to make a truly robust system with voting and prediction capability for a truly robust system and roll it into production and begin a retrofit program.

They could add a standalone AoA processor that takes the 4 inputs, processes them and outputs the result to the FCC using the current inputs. The FCC wouldn't need to be modified. The "AoA processor" could intentionally feed divergent results if it is unable to determine the AoA with enough reliability. Then, based on MCAS 2.0, the FCC would just disable MCAS and display an AoA disagree warning.

And how slowing down to flaps1 speed works with ETOPS?
 
TaromA380
Posts: 290
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri Jun 14, 2019 12:25 pm

What would be the next milestone in the matter ? Any planned international regulators press conference or something ?

By the way, when entering the jungle of complexity of "and if"s due to added automation on a non-FBW frame let's not forget that this is not fate. The world was pushed on this path by the strategic decision of not modifying anything (or almost anything) with the required training to fly the new version.
 
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Revelation
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri Jun 14, 2019 12:29 pm

ltbewr wrote:
Perhaps the Paris Air Show will have Boeing make announcements of a tentative schedule for RTS for the 737MAX.

Almost certainly not. I just posted a statement yesterday from an FAA spokesman saying they will not put a timeline on the return to service. Boeing almost certainly would not risk damaging their relationship with FAA by making an announcement that contradicts what the FAA just said. The airlines are one step removed and have a need to crew their aircraft so they have to make certain announcements, and as we have seen, these announcements are tentative.
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Wake now, discover that you are the song that the morning brings
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kalvado
Posts: 1803
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri Jun 14, 2019 12:36 pm

Revelation wrote:
ltbewr wrote:
Perhaps the Paris Air Show will have Boeing make announcements of a tentative schedule for RTS for the 737MAX.

Almost certainly not. I just posted a statement yesterday from an FAA spokesman saying they will not put a timeline on the return to service. Boeing almost certainly would not risk damaging their relationship with FAA by making an announcement that contradicts what the FAA just said. The airlines are one step removed and have a need to crew their aircraft so they have to make certain announcements, and as we have seen, these announcements are tentative.

Maybe not a timeline, but a broad update. What are the issues on the table, how is the process going - what is submitted, what is requested, status of EASA negotiations etc.
Hard to expect that from the company which redacts the list of US hot-and-high airports from public documents, though.
 
LH452
Posts: 21
Joined: Fri Mar 02, 2007 5:20 pm

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri Jun 14, 2019 12:48 pm

IF the FAA deemed the 737 Max too unstable to be used as a passenger aircraft and requested Boeing to come with a solution that later became the MCAS, how is the FAA going to accept a situation of AOA disagree that disables MCAS?
 
planecane
Posts: 993
Joined: Thu Feb 09, 2017 4:58 pm

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri Jun 14, 2019 12:48 pm

kalvado wrote:
planecane wrote:
kalvado wrote:
Not so fast. AoA failure and MCAS disabling are a relatively frequent scenario to require double failure analysis.
So, you need to consider, for example, what happens if AoA sensor is of -> MCAS off, airspeed unreliable, possibly altitude unreliable AND there is another moderate probability failure, e.g. engine out. How would lack of envelope protection play out in this example?


I don't disagree and that is why procedures and training must be developed to deal with the situation. The MCAS off NNC could be something as simple as slow to flaps 1 speed and set flaps 1 and divert to nearest airport. MCAS seems to have been determined not to be needed with flaps deployed since it was designed not to activate.

It would seem that the most likely time for an AoA sensor failure would be soon after takeoff. Either it will have been damaged on the ground, from FOD or a bird strike. I don't foresee a very high failure rate where suddenly a sensor goes whacko during cruise.

If I was in charge of Boeing, I would do what it takes to get the MAX back in the air now with MCAS 2.0 and procedures that will minimize the likelihood of a dangerous situation. Then, I would design the addition of a 3rd (or 3rd and 4th) AoA sensor to make a truly robust system with voting and prediction capability for a truly robust system and roll it into production and begin a retrofit program.

They could add a standalone AoA processor that takes the 4 inputs, processes them and outputs the result to the FCC using the current inputs. The FCC wouldn't need to be modified. The "AoA processor" could intentionally feed divergent results if it is unable to determine the AoA with enough reliability. Then, based on MCAS 2.0, the FCC would just disable MCAS and display an AoA disagree warning.

And how slowing down to flaps1 speed works with ETOPS?


It will need to be analyzed for sure. If it is determined that it is an exceedingly rare event for an AoA sensor to fail above 10,000 ft. I don't think it would be an issue since below that flight level the aircraft will either be very close to the departure airport or very close to the destination.

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