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pugman211
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Fri Nov 15, 2019 1:55 am

flipdewaf wrote:
dtw2hyd wrote:
jollo wrote:
Do you mean that the “natural” (aka unaugmented, bare airframe, no-MCAS) stall test requested by EASA and recommended by JATR has not been flown yet?


I bet the air show flights were with MCAS off, otherwise, MCAS would go crazy with that climb.

It’s quite a high deck angle but probably not all that high AoA.

Fred


Sent from my iPhone using Tapatalk


Surely it would've been with flaps 1 and MCAS inactive?? Maybe not for the steep bank turns though?
 
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Revelation
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Fri Nov 15, 2019 3:19 am

bob75013 wrote:
You mean the same pilots union that after the first crash, but before the second professed supreme confidence in the safety of the MAX, and the head of the union told the world that he had no reservations about putting his family on the plane?

Is that the union you mean???

Strange how a point of view can change when a pile of money is at stake.

kalvado wrote:
DM was in charge at time of both crashes, and anemic response to Lion crash is on him. I don't believe that (not) firing DM solves any problems, but he is not an innocent bystander in this case.

Unlike MCAS development flow and decisions, crash is an event CEO should be aware of. Moreso for the crash of a brand new product.

DM did not make a strong showing in front of Congress either.

He came across as evasive rather than forthcoming.

He came across as well coached rather than sincere.

He came across as a delegator rather than a leader.

He came across as a corporate chieftain that is more worried about damage control and future profits than he worries about product safety.

Like it or not, his face is the face of the MAX crisis.

I don't see how he keeps his job long term.
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
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oschkosch
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Fri Nov 15, 2019 6:41 am

Revelation wrote:
DM did not make a strong showing in front of Congress either.

He came across as evasive rather than forthcoming.

He came across as well coached rather than sincere.

He came across as a delegator rather than a leader.

He came across as a corporate chieftain that is more worried about damage control and future profits than he worries about product safety.

Like it or not, his face is the face of the MAX crisis.

I don't see how he keeps his job long term.




I fully agree. He will be going sooner or later. :checkmark:

Maybe DM is doing a stalling tactic (excuse the pun!) himself? The longer max is grounded, the longer he has a job? :stirthepot:
:stirthepot: :airplane: "This airplane is designed by clowns, who in turn are supervised by monkeys" :airplane: :stirthepot:
 
phollingsworth
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Fri Nov 15, 2019 6:58 am

WPIAeroGuy wrote:
phollingsworth wrote:
morrisond wrote:

Yes - based on the evidence we have it is not unstable - and may not be unstable close to stall with flaps up - it's just the stick force gets lighter than it is allowed - for example instead of taking 20 lbs of force to hold it it goes to say 18 lbs whereas by reg it should go to 22 - it does not go negative and the controls reverse.

At close to stall if you let go of the control column the nose will come down and it will return to its previous in trim aingle of attack and airspeed as far as we know.

The EASA test flights (where they have said they will test it without MCAS)should put an end to this argument if they allow RTS without aerodynamic changes.

It's not an ideal situation (lesser stick force) but in reality it should never lead to a stall (which all pilots should be able to recover from) and a fatal outcome due to all the other protection systems and warnings going off.


Stick force lightening, or more appropriately reduced static margin/increased control effectiveness is an inherent feature of all unadulterated aft swept wing aircraft as the AoA increases to near stall. This is due to spanwise flow. The tips unload first, this moves the effective mean aerodynamic cord inboard and further forward. This moves the neutral point of the aircraft forward. The result is the elevator inherently becomes more effective. Some aircraft have solved this with aerodynamic augmentation, e.g. vortex generators on the outboard wing, ventral strakes, etc. In other aircraft it isn't meaningful enough over the range of effective c.g. to matter, finally other aircraft have implemented active augmentation systems to solve this. In the case of the A330-600/A310 and the 767-2C, this involves stab trim driven by the FCC based on 3 AoA sensors. In the case of FBW aircraft it will be in the flight control software and generally opaque to the user. For some aircraft, particularly tailless designs, it is possible that the aircraft will become statically unstable. Keep in mind static stability and control effectiveness are slightly different, but highly related phenomena. Longitudinal pitch control effectiveness is highest when the aircraft is neutrally stable and decreases as the static margin increases or decreases from 0.

The simple way to check (though actually much harder than it sounds) static stability is to put the aircraft in trim and give a small pitch perturbation. If the aircraft returns to the original condition, or oscillates about the original point it is statically stable. This is true even if dynamically it eventually diverges or reaches a limit cycle. If it remains where it is or oscillates about the upset point it is neutral, if it moves further away or oscillates about a diverging point it is negatively stable. As long as you have to keep pulling back to get more pitch up your aircraft remains statically stable. If you have to push forward to stop it from pitching up you have a big problem. If as the angle of attack increases you have to push more and more forward to prevent it from diverging you have a really massive problem.

The fact is that the 737 exhibits classic reduced static stability at higher angles of attack. It does not, as far as any evidence I have seen, exhibit neutral or negative static stability. In fact given the way MCAS works if it were statically unstable by more than 1% or so, it is highly likely that the aircraft would have diverged, there just isn't enough bandwidth in MCAS to counter it. The reason we care about stick lightening, is that if it happens too rapidly it makes it much more likely, especially in high workload situations that the pilot might pull back just a bit too much and actually stall the aircraft.

One other thing, looking at the FDR traces on the two accidents it looks like a trim speed actually exists for full electronic nose down stabiliser. However, there was no way the aircraft would be able to have flown that fast.


Excellent description. I suspected that all airliners exhibit this to some extent but I don’t have data on hand. Interesting note though, it in the link I posted about stick forces it stated that the A330 and A350 had 0% static margin,I.e. neutral stability. I would suspect that isn’t quite true, however it’s probably close as any trim drag is going to result in increased fuel burn.


Given that’s its a feature of swept wings it will be there, to a greater or lesser extent, on all airliners. Underwing engines will exacerbate the problem. The 737 has always had issues with this approaching stall, though not as sever. You can see it in the platform and the leading edge devices. The MAX made it unacceptable in the clean configuration. As to the A330 and A350 being neutrally stable I am highly sceptical, especially the A350 which actually has a less sophisticated fuel trim system. The reason you wouldn’t want to be neutral in these aircraft is that it would be almost impossible to keep it from going negative. Add to that if you revert to alternate law the pilot would have to push forward. Speaking of going unstable there is a class of tailless, stealthy planforms, that are notorious for departing at high g-loading for just this reason. You have to have a low static margin not to get eaten on trail drag and the tips unload driving it negative. It quickly can overwhelm the available bandwidth even on totally augmented control systems.
 
pune
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Fri Nov 15, 2019 8:30 am

maint123 wrote:
So I was reading that the A350 flew for 2600 hrs (5 test planes), before the Europeans and the FAA certified it. Means at an average, each plane flew for more than 500 hrs. At 8 hrs of flight per day, equals 62 days of flying per plane. Is using 5 planes to test fly a industry standard, as using too many planes would reduce the stress and compromise the results.
Wonder how much hours of testing will the Max have to undergo before its recertified for flight.?


can you share link please of the article or newspaper report or site, thank you :)
 
pune
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Fri Nov 15, 2019 8:59 am

SomebodyInTLS wrote:
benbeny wrote:
Why do we need to test fly a plane when we have immense computational power to simulate it?


The short answer is because we *don't* have the computational power... and never will.

All simulation is based on human interpretation of what actually tends to happen in nature in real life. Unless you can build a computer model 100% accurately describing every interaction of every atom within the aircraft and all the airspace it interacts with you will always find that some assumption about how things behave or how humans behave or how manufacturing processes work in real life, etc. was not quite the same as in the real world.

Science is only as accurate as humans can make it by testing theories against the real world. And those tests bring changes... Newton becomes Einstein, the flat Earth becomes a globe, witchcraft becomes medicine. And the same with technology... the MCAS debacle is a result of assumptions not matching the real world - hence tests can never completely be replaced by simulation. QED.


well put. Hence real-life testing is much necessary than reel-life. Although would you argue that having spent considerable time in a sim may perhaps increase the pilot's awareness of the components, even though how the components behave in real-life may never be able to simulate in real-life
 
benbeny
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Fri Nov 15, 2019 10:50 am

pune wrote:
SomebodyInTLS wrote:
benbeny wrote:
Why do we need to test fly a plane when we have immense computational power to simulate it?


The short answer is because we *don't* have the computational power... and never will.

All simulation is based on human interpretation of what actually tends to happen in nature in real life. Unless you can build a computer model 100% accurately describing every interaction of every atom within the aircraft and all the airspace it interacts with you will always find that some assumption about how things behave or how humans behave or how manufacturing processes work in real life, etc. was not quite the same as in the real world.

Science is only as accurate as humans can make it by testing theories against the real world. And those tests bring changes... Newton becomes Einstein, the flat Earth becomes a globe, witchcraft becomes medicine. And the same with technology... the MCAS debacle is a result of assumptions not matching the real world - hence tests can never completely be replaced by simulation. QED.


well put. Hence real-life testing is much necessary than reel-life. Although would you argue that having spent considerable time in a sim may perhaps increase the pilot's awareness of the components, even though how the components behave in real-life may never be able to simulate in real-life


I mean engineering simulation. But I agree with your assumption.
 
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SomebodyInTLS
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Fri Nov 15, 2019 12:33 pm

pune wrote:
SomebodyInTLS wrote:
Science is only as accurate as humans can make it by testing theories against the real world. And those tests bring changes... Newton becomes Einstein, the flat Earth becomes a globe, witchcraft becomes medicine. And the same with technology... the MCAS debacle is a result of assumptions not matching the real world - hence tests can never completely be replaced by simulation. QED.


well put. Hence real-life testing is much necessary than reel-life. Although would you argue that having spent considerable time in a sim may perhaps increase the pilot's awareness of the components, even though how the components behave in real-life may never be able to simulate in real-life


You're mixing up flight simulation for training purposes with computer modelling for design purposes. The original question was about proving that the updated MCAS would perform properly in actual conditions - the reply about "we can simulate anything with computers, no need to test" implies a computer model of the aircraft in flight for testing the design.Your point about pilots and training sims is a different thing.

Having said that, I do agree that including MCAS behaviour in a sim and training for it will certainly help pilots react appropriately - but that's assuming a) that the sim models MCAS behaviour properly (no bad assumptions like those made by the original engineers!) and b) that the sim models the aircraft behaviour accurately in approach-to-stall conditions. It's my understanding that flight sims - because they are based on simplified models - can not accurately reproduce aircraft behaviour in a stall, so b) might be tricky.
"As with most things related to aircraft design, it's all about the trade-offs and much more nuanced than A.net likes to make out."
 
pune
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Fri Nov 15, 2019 1:19 pm

SomebodyInTLS wrote:
--snipped --

You're mixing up flight simulation for training purposes with computer modelling for design purposes. The original question was about proving that the updated MCAS would perform properly in actual conditions - the reply about "we can simulate anything with computers, no need to test" implies a computer model of the aircraft in flight for testing the design.Your point about pilots and training sims is a different thing.

Having said that, I do agree that including MCAS behaviour in a sim and training for it will certainly help pilots react appropriately - but that's assuming a) that the sim models MCAS behaviour properly (no bad assumptions like those made by the original engineers!) and b) that the sim models the aircraft behaviour accurately in approach-to-stall conditions. It's my understanding that flight sims - because they are based on simplified models - can not accurately reproduce aircraft behaviour in a stall, so b) might be tricky.


I meant reel-life in my earlier quote at the second which you responded to and probably got the quote I was responding to.

While I'm just a person of flying public, I do believe the idea of reacting under 3 seconds or less is putting more than undue pressure on the pilot. Apart from the whole debate of whether or not MCA's and its implementation is good or bad, the other fact is climate change may also be adding pressures to the pilot's job.

I also do not know how much, but one cannot discount the possibility that nowadays due to climate change pilots may have to alter the original flight plans filed. And as shared by people on the board in the same thread that climate science and weather prediction is hard.

I do believe that Boeing hopefully brings shares more training material with the airlines and the European safety regulators give their blessing or go-ahead. Some may believe and it might be also partly true that the European safety regulators may be harsher as Airbus continues to profit. For the flying public though, the European safety regulations have meant that they have been more safer flying experience. FWIW, I would be comfortable on the Airbus aircraft rather than the Boeing at least for year or two till there are no crashes even with the 737 Max certified safe.
 
benbeny
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Fri Nov 15, 2019 1:23 pm

pugman211 wrote:
flipdewaf wrote:
dtw2hyd wrote:

I bet the air show flights were with MCAS off, otherwise, MCAS would go crazy with that climb.

It’s quite a high deck angle but probably not all that high AoA.

Fred


Sent from my iPhone using Tapatalk


Surely it would've been with flaps 1 and MCAS inactive?? Maybe not for the steep bank turns though?

Remember, MCAS is a function dependent on AoA. If they had AoA high enough for MCAS to activate, the stick shaker would have been screaming at them constantly.
 
YouGeeElWhy
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Fri Nov 15, 2019 1:31 pm

https://www.dallasnews.com/business/air ... g-737-max/


Some American Airlines flight attendants are 'begging’ not to fly the Boeing 737 Max

Their union president says some are scared to fly it again. Meanwhile, Southwest pilots blast Boeing for ‘arrogance, ignorance and greed.’
 
dtw2hyd
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Fri Nov 15, 2019 1:35 pm

benbeny wrote:
pugman211 wrote:
flipdewaf wrote:
It’s quite a high deck angle but probably not all that high AoA.

Fred


Sent from my iPhone using Tapatalk


Surely it would've been with flaps 1 and MCAS inactive?? Maybe not for the steep bank turns though?

Remember, MCAS is a function dependent on AoA. If they had AoA high enough for MCAS to activate, the stick shaker would have been screaming at them constantly.


And any below-average pilot knows how to deal with stall without MCAS.
Was MCAS design in place before the first MAX test flight or an afterthought after the first few test flights?

Like I posted in the past, the crew was presented with three scenarios contradicting each order.

Stick shaker - Stall - Nose down
Runaway Stabilizer - Stab wheel trim down - Nose up
Mistrim - Control column pressure/unable to move stab trim - Rollacoaster move.

And they were expected to pick the and correct warning and the corrective action.
All posts are just opinions.
 
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PixelFlight
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Fri Nov 15, 2019 2:28 pm

benbeny wrote:
pugman211 wrote:
flipdewaf wrote:
It’s quite a high deck angle but probably not all that high AoA.

Fred


Sent from my iPhone using Tapatalk


Surely it would've been with flaps 1 and MCAS inactive?? Maybe not for the steep bank turns though?

Remember, MCAS is a function dependent on AoA. If they had AoA high enough for MCAS to activate, the stick shaker would have been screaming at them constantly.

Have you read the MCAS nose down increments table schedule as a function of AoA and Mach ?
If yes, please provides the values. This would respond to a lot of questions here.
If no, you can't have any certitude on your claim as the MCAS into the FCC and the stick shaker into the SMYD are two completely separated systems in different computers.
My personal guess is that your claim is not true for every values.
: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:
 
Sooner787
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Fri Nov 15, 2019 2:52 pm

YouGeeElWhy wrote:
https://www.dallasnews.com/business/airlines/2019/11/14/some-american-airlines-flight-attendants-are-begging-not-to-fly-the-boeing-737-max/


Some American Airlines flight attendants are 'begging’ not to fly the Boeing 737 Max

Their union president says some are scared to fly it again. Meanwhile, Southwest pilots blast Boeing for ‘arrogance, ignorance and greed.’


I'm sure the FA's will be included in the followup training their airlines will have for their flight crews
before they resume service. Hopefully, that alleviates their concerns.

The airlines had also better be ready to offer no fee change waivers for any passengers who don't want to fly
on a MAX for the 60-90 days after service resumes.
 
maint123
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Fri Nov 15, 2019 3:23 pm

pune wrote:
maint123 wrote:
So I was reading that the A350 flew for 2600 hrs (5 test planes), before the Europeans and the FAA certified it. Means at an average, each plane flew for more than 500 hrs. At 8 hrs of flight per day, equals 62 days of flying per plane. Is using 5 planes to test fly a industry standard, as using too many planes would reduce the stress and compromise the results.
Wonder how much hours of testing will the Max have to undergo before its recertified for flight.?


can you share link please of the article or newspaper report or site, thank you :)

https://www.airbus.com/aircraft/how-is- ... ation.html
Though I had read some other article.
 
BravoOne
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Fri Nov 15, 2019 3:28 pm

 
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seahawk
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Fri Nov 15, 2019 4:19 pm

Revelation wrote:
bob75013 wrote:
You mean the same pilots union that after the first crash, but before the second professed supreme confidence in the safety of the MAX, and the head of the union told the world that he had no reservations about putting his family on the plane?

Is that the union you mean???

Strange how a point of view can change when a pile of money is at stake.

kalvado wrote:
DM was in charge at time of both crashes, and anemic response to Lion crash is on him. I don't believe that (not) firing DM solves any problems, but he is not an innocent bystander in this case.

Unlike MCAS development flow and decisions, crash is an event CEO should be aware of. Moreso for the crash of a brand new product.

DM did not make a strong showing in front of Congress either.

He came across as evasive rather than forthcoming.

He came across as well coached rather than sincere.

He came across as a delegator rather than a leader.

He came across as a corporate chieftain that is more worried about damage control and future profits than he worries about product safety.

Like it or not, his face is the face of the MAX crisis.

I don't see how he keeps his job long term.


That is the biggest problem for Boeing right now. The technical problems can be fixed, but they have tainted their image considerably imho. They came across as greedy, dishonest and lacking empathy. The damaged caused to the company´s image is imho massive.
 
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PW100
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Fri Nov 15, 2019 4:28 pm

Revelation wrote:
bob75013 wrote:
You mean the same pilots union that after the first crash, but before the second professed supreme confidence in the safety of the MAX, and the head of the union told the world that he had no reservations about putting his family on the plane?

Is that the union you mean???

Strange how a point of view can change when a pile of money is at stake.


Did their point of view change because there was money involved?

Or did the money thing came into play once they had changed their mind already?
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SheikhDjibouti
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Fri Nov 15, 2019 5:27 pm

BravoOne wrote:

Yeah, yeah, it's all been covered already. Several times.

Oh wait - your post doesn't give us any clue what the article is about...… :roll:
Nothing to see here; move along please.
 
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Revelation
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Fri Nov 15, 2019 5:42 pm

pune wrote:
While I'm just a person of flying public, I do believe the idea of reacting under 3 seconds or less is putting more than undue pressure on the pilot.

Yes, and both Boeing and FAA admit it was a mistake to deliver a system that put so much burden on the pilots, yet AFAIK the three second standard was not banned so you have to be cognizant that there are still different scenarios on various aircraft that still assume pilots will remember memory items and will respond in a timely fashion. The scenario where bad AoA data went unchecked and triggered MCAS repeatedly with great authority is certainly a disastrous outlier, hopefully the last such one, but we can't be sure of that.

pune wrote:
I do believe that Boeing hopefully brings shares more training material with the airlines and the European safety regulators give their blessing or go-ahead. Some may believe and it might be also partly true that the European safety regulators may be harsher as Airbus continues to profit. For the flying public though, the European safety regulations have meant that they have been more safer flying experience. FWIW, I would be comfortable on the Airbus aircraft rather than the Boeing at least for year or two till there are no crashes even with the 737 Max certified safe.

EASA has done a great job of being firm but fair and I presume that will continue throughout the RTS process.
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
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kalvado
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Fri Nov 15, 2019 5:56 pm

Revelation wrote:
pune wrote:
While I'm just a person of flying public, I do believe the idea of reacting under 3 seconds or less is putting more than undue pressure on the pilot.

Yes, and both Boeing and FAA admit it was a mistake to deliver a system that put so much burden on the pilots, yet AFAIK the three second standard was not banned so you have to be cognizant that there are still different scenarios on various aircraft that still assume pilots will remember memory items and will respond in a timely fashion. The scenario where bad AoA data went unchecked and triggered MCAS repeatedly with great authority is certainly a disastrous outlier, hopefully the last such one, but we can't be sure of that.

pune wrote:
I do believe that Boeing hopefully brings shares more training material with the airlines and the European safety regulators give their blessing or go-ahead. Some may believe and it might be also partly true that the European safety regulators may be harsher as Airbus continues to profit. For the flying public though, the European safety regulations have meant that they have been more safer flying experience. FWIW, I would be comfortable on the Airbus aircraft rather than the Boeing at least for year or two till there are no crashes even with the 737 Max certified safe.

EASA has done a great job of being firm but fair and I presume that will continue throughout the RTS process.

THere is an explanation floating around that 3 second is actually not time to hit kill switch, but time to counteract with yoke - and so use yoke switches to stop the trim.
Otherwise 3 seconds basically means lack of cockpit interaction and pressing random switches in emergency. Just try to tell your wife/gf/whoever else in your household that you need to turn lights off, and actually do so - all within 3 seconds.
 
shmerik
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Fri Nov 15, 2019 6:14 pm

kalvado wrote:
THere is an explanation floating around that 3 second is actually not time to hit kill switch, but time to counteract with yoke - and so use yoke switches to stop the trim.
Otherwise 3 seconds basically means lack of cockpit interaction and pressing random switches in emergency. Just try to tell your wife/gf/whoever else in your household that you need to turn lights off, and actually do so - all within 3 seconds.


Here's a good article going in-depth about how Boeing may have formed their assumptions around the 3 second reaction time and the relation to the column cutout switches:

https://www.satcom.guru/2019/10/flawed- ... aster.html
 
ClubCX
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Fri Nov 15, 2019 6:25 pm

flybynight wrote:
The news just isn't getting better for Boeing.
Even loyal partners are potentially looking elsewhere (or it is a negotiation tactic) -https://www.king5.com/article/tech/science/aerospace/boeing/leader-of-pilots-union-blasts-boeing-over-grounded-737-max/281-288a339e-5d1e-4bcd-9211-f9a37786d7d5


50+ 737 NGs are grounded because cracks have been found in the fuselage. I'm sure people are wondering if this will also happen with the MAX in a few years. Testing on the new 777x was suspended because a door blew off during a pressure test. Workers in Boeing factories are blowing the whistle on shoddy construction and saying they wouldn't fly on the 787 knowing how it's built. This isn't just an issue with one piece of software on one model, it's a Boeing issue.
 
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par13del
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Fri Nov 15, 2019 6:51 pm

ClubCX wrote:
Workers in Boeing factories are blowing the whistle on shoddy construction and saying they wouldn't fly on the 787 knowing how it's built.

We the travelling public can only hope that these Boeing workers are also naming these non-Boeing workers who are doing the shoddy construction.
 
djm18
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Fri Nov 15, 2019 7:13 pm

Revelation wrote:
He came across as evasive rather than forthcoming.

He came across as well coached rather than sincere.

He came across as a delegator rather than a leader.

He came across as a corporate chieftain that is more worried about damage control and future profits than he worries about product safety.

Like it or not, his face is the face of the MAX crisis.

I don't see how he keeps his job long term.


Agreed, I had started a thread about what it would take to make Boeing great again and to me this is a central issue. I have always hoped that Boeing would emerge stronger from this crisis, but at present I have very serious doubts. I think they will ultimately get it right on the technical side but Boeing no longer has the reputation it once had. And DM has simply not proven himself to be the person to lead the company through this crisis.
 
oschkosch
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Fri Nov 15, 2019 8:49 pm

Very interesting news from FAA. Looks like the FAA is showing they have a backbone and are pushing Boeing's latest statements back. I consider that very positive for a safety first approach.

https://www.cnbc.com/2019/11/15/reuters ... -memo.html


U.S. Federal Aviation Administrator Steve Dickson told his team to “take whatever time is needed” in their review of Boeing Co’s 737 MAX, reiterating that the path to approval is “not guided by a calendar or schedule,” according to a Nov. 14 memo reviewed by Reuters.

The memo was sent to Ali Bahrami, a top FAA safety official, and follows a statement by Boeing on Monday saying that the FAA could approve in December fixes to software that played a role in two fatal crashes of the 737 MAX.

 In a video posted on YouTube on Friday, Dickson said: “I am not gonna sign off on this aircraft until I fly it myself and I am satisfied that I would put my own family on it without a second thought.”
The 737 MAX has been grounded worldwide since March. Addressing FAA employees, Dickson said the only driving force is safety. As I've said to all of you, I support what you are doing to scrutinize this aircraft very carefully. And I'll support the time that you need to conduct a thorough, deliberate process for a safe return to service.




Gesendet von meinem SM-G950F mit Tapatalk
:stirthepot: :airplane: "This airplane is designed by clowns, who in turn are supervised by monkeys" :airplane: :stirthepot:
 
art
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Fri Nov 15, 2019 8:58 pm

Sooner787 wrote:
The airlines had also better be ready to offer no fee change waivers for any passengers who don't want to fly
on a MAX for the 60-90 days after service resumes.

Why? If you fly a route using MAX, how can you offer a different aircraft to pax? Or do you mean give the pax his/her money back so they can book on an airline using a different type on the route?

I have no idea how pax will react at the airport if they realise they unwittingly booked a flight on a MAX. What proportion are going to refuse to get on the plane? Simplest thing IMO would be if before accepting a booking airlines could make it known to pax that they may/will be flying on a MAX.
 
art
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Fri Nov 15, 2019 9:19 pm

oschkosch wrote:
Very interesting news from FAA. Looks like the FAA is showing they have a backbone and are pushing Boeing's latest statements back. I consider that very positive for a safety first approach.


What really matters to me in the report is this unequivical statement:

Addressing FAA employees, Dickson said the only driving force is safety.


https://www.cnbc.com/2019/11/15/reuters ... -memo.html
 
MSPNWA
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Fri Nov 15, 2019 9:40 pm

ClubCX wrote:
50+ 737 NGs are grounded because cracks have been found in the fuselage. I'm sure people are wondering if this will also happen with the MAX in a few years. Testing on the new 777x was suspended because a door blew off during a pressure test. Workers in Boeing factories are blowing the whistle on shoddy construction and saying they wouldn't fly on the 787 knowing how it's built. This isn't just an issue with one piece of software on one model, it's a Boeing issue.


You illustrate a danger with news stories that create a potentially false narrative. Is it really abnormal? Is it really a problem? Are there ulterior reasons at play for people to say such things? Are they actually common events that happen anywhere that would never make the news if Boeing wasn't currently a target? Every point can be rebuffed as one of them, and the narrative is shown to be false. Then the conclusion reverses, and the rest of the evidence shows that Boeing is a very strong and healthy company that hit a big bump with the MAX software error.


oschkosch wrote:
Very interesting news from FAA. Looks like the FAA is showing they have a backbone and are pushing Boeing's latest statements back. I consider that very positive for a safety first approach.

https://www.cnbc.com/2019/11/15/reuters ... -memo.html


Caring about politics or the image of a situation isn't safety. It's only the appearance of safety, hoping the public will believe it. Take Dickson's comment for example. It's clearly about image when you think about it. Is the MAX officially safer because he - one who doesn't have the expertise and knowledge about the MAX that the FAA as a whole does - personally flew it first? And if he doesn't sign off, is he some kind of dictator to stop it?

So, no, I don't see a backbone here. I see image and politics.
 
smokeybandit
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Fri Nov 15, 2019 10:41 pm

Certainly that comment was purely for show. He's basically saying "Boeing, we're controlling the calendar for return to service, not you, even if our timeline ends up the same as yours"
 
maint123
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Sat Nov 16, 2019 3:50 am

"Boeing is a very strong and healthy company that hit a big bump with the MAX software error"
Software or logic error ?
And has anyone categorically said what will happen to the aerodynamics of max if MCAS is removed or stopped in flight ? Do pilots really need the help from mcas ? Basically if the Max can fly OK without mcas , why keep a potentialy disaster prone system?
 
prebennorholm
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Sat Nov 16, 2019 5:08 am

maint123 wrote:
Do pilots really need the help from mcas ? Basically if the Max can fly OK without mcas , why keep a potentialy disaster prone system?
You can build aircraft which react sensibly to control inputs, and you can build them with difficult or confusing relations between control input and behavior. The regulators demand a minimum of sensibility for certification, and the MAX sans MCAS simply does not meet that minimum. MCAS corrects that.

MCAS as such is not a disaster prone system. It just needs a valid AoA angle as input, or a signal telling that an AoA angle is not available. That is exactly the input which MCAS 2.0 will enjoy. MCAS 1.0 sadly didn't have that "luxury input", but only a single input channel acting according to the bad old "garbage in, garbage out" principle.

That said, it wouldn't surprise me if - due to the MAX events - it lasts at least a hundred years before a plane producer again dares to produce a new plane type which needs such artificial augmentation of manual (non-FBW) control in order to comply with basic control quality regulation. That way they will save a lot of time and other expensive resources which the regulators otherwise will spend on validating the quality and robustness of such artificial augmentation systems.

For the MAX the latter would have meant that the engines would have been positioned differently under the wing in a way to make their aerodynamic reaction on pitch identical to the NG, and a higher landing gear to fit. (And end of grandfathering of slideless overwing exits, and, and, and.....)
Always keep your number of landings equal to your number of take-offs
 
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SEPilot
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Sat Nov 16, 2019 6:08 am

prebennorholm wrote:
maint123 wrote:
Do pilots really need the help from mcas ? Basically if the Max can fly OK without mcas , why keep a potentialy disaster prone system?
You can build aircraft which react sensibly to control inputs, and you can build them with difficult or confusing relations between control input and behavior. The regulators demand a minimum of sensibility for certification, and the MAX sans MCAS simply does not meet that minimum. MCAS corrects that.

MCAS as such is not a disaster prone system. It just needs a valid AoA angle as input, or a signal telling that an AoA angle is not available. That is exactly the input which MCAS 2.0 will enjoy. MCAS 1.0 sadly didn't have that "luxury input", but only a single input channel acting according to the bad old "garbage in, garbage out" principle.

That said, it wouldn't surprise me if - due to the MAX events - it lasts at least a hundred years before a plane producer again dares to produce a new plane type which needs such artificial augmentation of manual (non-FBW) control in order to comply with basic control quality regulation. That way they will save a lot of time and other expensive resources which the regulators otherwise will spend on validating the quality and robustness of such artificial augmentation systems.

For the MAX the latter would have meant that the engines would have been positioned differently under the wing in a way to make their aerodynamic reaction on pitch identical to the NG, and a higher landing gear to fit. (And end of grandfathering of slideless overwing exits, and, and, and.....)

There will never be another non-FBW airliner as a new design. The only possibility on the horizon for a new non-FBW variant is the 767 getting GenX engines, and I think that is someone’s pipe dream. I think Boeing is going to start serious work on the 737 replacement; they have little choice at this point. They have no time for playing with the 767 which would only sell a couple hundred frames at best.
The problem with making things foolproof is that fools are so doggone ingenious...Dan Keebler
 
art
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Sat Nov 16, 2019 10:15 am

SEPilot wrote:
I think Boeing is going to start serious work on the 737 replacement; they have little choice at this point..


But with no step change engine to harness for a dramatic improvement in fuel consumption (as in Leap or GTF when NEO and MAX were developed), what happens when significantly better engines become available nearer 2030 than now? That would leave an NEO successor that took advantage of engine advances with a definite edge over the MAX replacement. That would put Boeing into the position they were in when the A320NEO was launched - the root cause of the rushed development of the MAX.

Would there be a way for Boeing to design a MAX replacement with an eye to making it easier to switch to more advanced engines when the next generation of engines becomes available? Could the aircraft design not take into account the need for a later engine of increased fan size to be relatively easily substituted? Perhaps Boeing should design an aircraft optimised for a larger engine and adapt that design to use Leap or GTF while awaiting the next generation of engines.
 
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SEPilot
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Sat Nov 16, 2019 10:28 am

art wrote:
SEPilot wrote:
I think Boeing is going to start serious work on the 737 replacement; they have little choice at this point..


But with no step change engine to harness for a dramatic improvement in fuel consumption (as in Leap or GTF when NEO and MAX were developed), what happens when significantly better engines become available nearer 2030 than now? That would leave an NEO successor that took advantage of engine advances with a definite edge over the MAX replacement. That would put Boeing into the position they were in when the A320NEO was launched - the root cause of the rushed development of the MAX.

Would there be a way for Boeing to design a MAX replacement with an eye to making it easier to switch to more advanced engines when the next generation of engines becomes available? Could the aircraft design not take into account the need for a later engine of increased fan size to be relatively easily substituted? Perhaps Boeing should design an aircraft optimised for a larger engine and adapt that design to use Leap or GTF while awaiting the next generation of engines.

Any 737 replacement will be designed to accommodate much larger engines. I think that the NSA (in Boeing palrlance) and the A320 are both going to be able to accommodate any likely future engines relatively easily. I see it as highly unlikely that any new disruptive engine technology is going to emerge any time soon that will not fit on the wings of these two airframes. But Boeing needs to come up with an airframe for which this is true. That airframe is not the 737. The goal of getting 15% improvement will have to be sacrificed in order to just stay in the narrowbody market.
The problem with making things foolproof is that fools are so doggone ingenious...Dan Keebler
 
Nick1209
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Sat Nov 16, 2019 10:37 am

77H wrote:
Nick1209 wrote:
Hoping and Relying on the ECAA won’t do much. Just look what those goons did with EgyptAir 990. Are we really expecting them to come up with an actual conclusion? They’re probably looking for dirt on Boeing far more than investigating the accident.

There’s a reason why Lion Air rushed to the families after the incident, and forced them to sign papers agreeing not to sue them, nor Boeing. They simply didn’t wanna ruin their relationship with Boeing over something their pilots should have known. Like not selling them anymore aircraft till they prove otherwise. All the talk from airlines regarding the max is just politics. I remember what the CEO for United said right after the incident too lol.

If we wanted to make sure every plane was perfectly built, then we would be grounding every single one. I can’t even begin to tell you how many aircraft have been cleared to fly that have “design flaws” but haven’t affected a single flight today. Not even Boeing’s “design flaw” affected either accident. It wasn’t the engines that caused the plane to crash. They both had a software malfunction. Which is Impossible to prevent. And any malfunction that is improperly handled, will end up the same way. Both of which were handled improperly. To me, this is more important that what happened at Boeing because even a perfectly designed and certified airplane can have failures and the crews are the ones who are left to handle them. Crews must be prepared to handle whatever emergency we are presented with, even those like UAL232, Aloha 243, Qantas 32, Qantas 72, and SWA1380 which were failures that were never anticipated and for which no crew had ever been trained.

So how much longer are we going to act like the crashes were very controllable, and entirely preventable? Of which happened in third world countries andone FO with a low amount of hours, flying the plane.

Regardless, neither crew completed a single step on their procedures for runaway stabilizer OR unreliable airspeed. Both of which have to be done in a reasonably manner to prevent an accident.

Lions crew knew what procedure to follow, but forgot it. As you can see on the final report. What I wanted to know, was why did the Captain keep them in trim through 21 MCAS activations, but the FO, to whom took control, did not. Neither of them went to their procedure. We know why though, now. Because they forgot it. Sounds like Lion Air if you ask me, just how many times have their pilots missed the runway, and confused the ocean for the runway? And how many drug charges have been in the news for their pilots?

Let’s not forget that Boeing promised the Max would come without any additional training. And the issues with the engine position was nonexistent till the end of certification. It wasn’t until the stick force per g, which involves banking the aircraft and pulling back on the yoke, and of course banking more and pulling back more, it should be harder to pull back each time, and never easier. But because of Boeing’s engine positioning, an aerodynamic nose up appeared. This nose up created a feeling of it being easier to pull back. The aircraft didn’t Meet FAA longitudinal stability anymore. So the easiest fix was to add some nose down. So it’s quite comical to watch the media call it a “stall prevention system” which is far from true. Just because Airbus has one, and calls it that, and yes, they’ve killed people with their system as well, but doesn’t mean it’s the same for Boeing. Their products do not need a stall prevention system nor recovery system. They’ll recover a stall with the control column in neutral.

Boeing figured one sensor shouldn’t be too bad, after all, the issue would appear itself as a runaway trim and there’s a procedure for that, and it has been around for 5 decades. Shouldn’t be too difficult for pilots already typed in the aircraft, right? Well they under looked these third world countries and the training issues they have. Oops. And it’s not like the system in Airbus aircraft, ya know? Like the one where the crews gotta call to the ground team to figure out what’s going on, who’s hiding systems? Airbus has been dealing with the same and has already been told by both US and Europe to fix it, but haven’t. So while everyone expects Boeing to fix this issue in under a year, Airbus hasn’t fixed theirs, in over 10 years now. Could it be, that designing an aircraft is just difficult? Nah, totally easy. Anyone can do it and Boeing should have knew better. It’s not like airlines had the option to purchase a second sensor but chose not to, and how did the airlines know to buy one or two? The 737 has always looked at one sensor the same way the Max did. It was just based off whoever was flying the plane.

It’s not like the Brazilian authority has MCAS on paper and listed as “B” training from January 2018. Besides all of that, the runaway stabilizer procedure has been the same and hardly changes. As you guys probably already know, the procedure that will disable MCAS. And Ethiopias crew knew it, because they verbalized it, and did it, and undid it. Then accelerated beyond the design limit and crashed. Blame Boeing. If anything, we can say Lions crew had the harder battle due to them not “knowing” not considering the fact that it literally the same as a runaway stab malfunction. Ethiopias crew was already reminded of the issue, due to the Lion crash. Boeing highlighted the issues on the checklist. And sent it out. It’s important that airlines inform their pilots of the new changes

That say “In the event of an uncommanded nose pitch down, hit the stab trim cut out switches to CUTOFF and stay in the CUTOUT position for remainder of flight” yet Ethiopias crew battled with the entire issue until it was near full nose down, then they cut out the switches. They also skipped over step 2 which was too disengage auto throttles, and that allowed the aircraft to fly to and past VMO and out of the flights envelope. Increasing nose down trim and increasing airspeed will result in a stronger nose down force. It’s also clear that when the FO took control, after hitting the cut out switches, he trimmed in the WRONG DIRECTION. And told his captain “it’s not working” followed by his captain saying “pitch up with me”

One of them re engaged the stab trim switches, and that allowed MCAS to reactivate and drive the nose down back down, and it did. Despite them knowing what was going on, and the entire procedure, and lions crash, they still failed the aircraft. I’m not trying to be harsh, but the blame is all going on Boeing when it shouldn’t. It’s clear there’s enough blame to around here. And allowing such training issues to go unnoticed is going to be a disaster for the aviation industry.


You seem very eager to point the blame at the pilots and cite deficient training and lack of experience (hours) amongst crews at airlines operating in 3rd world countries while seemingly casting aside any culpability on Boeing’s end.

My understanding is that there are a plethora of 3rd world airlines operating the 737NG , 32x CEO and 32x NEO in their fleets. How many instances can you cite where a 737NG, or 32x, operated by a 3rd world airline was turned into a lawn dart ? How do you suppose these 3rd world crews can safely operate thousands of NGs, CEOs and NEOs everyday but somehow they managed to plow 2 MAXs into the ground within half a years time ?

If poor training and lack of experience amongst 3rd world crew members is as big of a problem as you seem to claim, isn’t it reasonable to expect we would see higher numbers of catastrophic hull losses from other variants operated by these airlines. 3rd world airlines have massive fleets of 32x NEOs in their fleets. Given your stance, I assume you feel the NEO is 3rd world pilot proof given there hasn’t been a single hull loss, and thusly a superior aircraft ?

And before you go off citing Lion Air’s runway excursion incidents and attributing that to their status as a 3rd world airline you really ought to consider WN is usually good for an excursion or 2 every year. Beyond that, they have 2 very high profile runway excursions in their history (BUR/MDW). DL had a rather violent one at LGA a few years back too. I suppose you consider WN and DL 3rd world ?

Moreover, I could cite a number of US airlines that have had accidents/incidents, some resulting in fatalities due to poor maintenance. Again at the forefront of my mind is WN. To use your own examples, correct me if I’m wrong but wasn’t it an improperly installed fan blade on UA232 that ultimately led to the crash? AQ243 had metal fatigue so extreme that a passenger noticed a crack prior to take off that ultimately led to the top of the fuselage peeling back. If a passenger noticed such wear and tear certainly the maintenance team should have. I guess we can add United and the now defunct Aloha to the list of 3rd world airlines.

Almost forgot, you brought up questionable professional conduct by crews of 3rd world airlines to, citing drug charges was it ? I seem to recall several threads just this year regarding several US crews being arrested at the airport attempting to board their aircraft intoxicated... Oh and let’s not such professional conduct like the US crew that overflew their destination by approximately 150 miles or another that landed at the wrong airport.

Speaking candidly your posts sound quite ignorant.

77H



Lol, except the fact that shady shit goes unnoticed a lot longer in those countries than they do here.

3rd world or not, crashes happen, and yes there are accidents here in the US and Europe, but do we see accidents from failing a basic procedure like the one presented? No. You never would. Fact. Would European or American crews forget throttles in full? No. Would they not only leave throttle at full, but try to manually trim the aircraft like that? No. Would they fly out of the envelope and still try to manually trim? No. Would the F/O trim in the wrong direction? No. Would either reverse a procedure that’s been well known to never reverse? No. These accident crews performed extremely Hmmmm horribly, and as pilots we have the job to ensure a safe outcome for the flight. In some cases, it can be understandable. It is not understandable in the slightest form here. Some people forget what it takes to become a pilot, or the importance of having reliable, and trained pilots. It’s almost like you guys are okay with the ways these airlines train their pilots. You put either accident crew in UA232 position, guess what? Everyone is dead. Gone. You put the pilots in JT610 position. Landed. You put the pilots of UA232 in ET302 position, landed. Fact.
 
Nick1209
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Sat Nov 16, 2019 10:38 am

AoA disagree was supposed to be standard warning, AoA indicator was a premium feature. Due to programming error, AoA disagree didn't work as designed without a premium feature purchased.
Loss of control over design at its best.[/quote]

The AoA disagree would have done nothing. The crew had every symptom for unreliable airspeed and didn’t flow the checklist either. There is no procedure to utilize the AoA anyway
 
Nick1209
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Sat Nov 16, 2019 10:57 am

B777LRF wrote:
Nick1209 wrote:
I believe it’s a business tactic pure and simple. The military doesn’t care how much they spend in the end. Airlines do. Airlines didn’t buy the second sensor although they had a choice to, for a reason. And Boeing knew it wouldn’t go over well with them, as shown, because in the end they didn’t purchase the sensor.


I'm not sure if it's a tactic or blatant arrogance, but the latter part of your argument is not a true representation. There was no option to buy a second sensor; there was an option to buy an AoA indicator. There was also an option to buy an AoA disagree warning, which was taken up by at least Southwest. Problem was, it didn't work because there was no independent box to compare the signals from both AoA sensors, and the FCC ran on the signal from only one of them. Nice one.


Southwest doesn’t have it. Nor any airline in the US. Only one does and it’s none of them.

The 737 has always looked at AoA sensors the same way the max does. Simultaneously. Whatever side the flying pilot is on, and then vice versa once the other takes control.
 
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seahawk
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Sat Nov 16, 2019 11:04 am

Nick1209 wrote:
77H wrote:
Nick1209 wrote:
Hoping and Relying on the ECAA won’t do much. Just look what those goons did with EgyptAir 990. Are we really expecting them to come up with an actual conclusion? They’re probably looking for dirt on Boeing far more than investigating the accident.

There’s a reason why Lion Air rushed to the families after the incident, and forced them to sign papers agreeing not to sue them, nor Boeing. They simply didn’t wanna ruin their relationship with Boeing over something their pilots should have known. Like not selling them anymore aircraft till they prove otherwise. All the talk from airlines regarding the max is just politics. I remember what the CEO for United said right after the incident too lol.

If we wanted to make sure every plane was perfectly built, then we would be grounding every single one. I can’t even begin to tell you how many aircraft have been cleared to fly that have “design flaws” but haven’t affected a single flight today. Not even Boeing’s “design flaw” affected either accident. It wasn’t the engines that caused the plane to crash. They both had a software malfunction. Which is Impossible to prevent. And any malfunction that is improperly handled, will end up the same way. Both of which were handled improperly. To me, this is more important that what happened at Boeing because even a perfectly designed and certified airplane can have failures and the crews are the ones who are left to handle them. Crews must be prepared to handle whatever emergency we are presented with, even those like UAL232, Aloha 243, Qantas 32, Qantas 72, and SWA1380 which were failures that were never anticipated and for which no crew had ever been trained.

So how much longer are we going to act like the crashes were very controllable, and entirely preventable? Of which happened in third world countries andone FO with a low amount of hours, flying the plane.

Regardless, neither crew completed a single step on their procedures for runaway stabilizer OR unreliable airspeed. Both of which have to be done in a reasonably manner to prevent an accident.

Lions crew knew what procedure to follow, but forgot it. As you can see on the final report. What I wanted to know, was why did the Captain keep them in trim through 21 MCAS activations, but the FO, to whom took control, did not. Neither of them went to their procedure. We know why though, now. Because they forgot it. Sounds like Lion Air if you ask me, just how many times have their pilots missed the runway, and confused the ocean for the runway? And how many drug charges have been in the news for their pilots?

Let’s not forget that Boeing promised the Max would come without any additional training. And the issues with the engine position was nonexistent till the end of certification. It wasn’t until the stick force per g, which involves banking the aircraft and pulling back on the yoke, and of course banking more and pulling back more, it should be harder to pull back each time, and never easier. But because of Boeing’s engine positioning, an aerodynamic nose up appeared. This nose up created a feeling of it being easier to pull back. The aircraft didn’t Meet FAA longitudinal stability anymore. So the easiest fix was to add some nose down. So it’s quite comical to watch the media call it a “stall prevention system” which is far from true. Just because Airbus has one, and calls it that, and yes, they’ve killed people with their system as well, but doesn’t mean it’s the same for Boeing. Their products do not need a stall prevention system nor recovery system. They’ll recover a stall with the control column in neutral.

Boeing figured one sensor shouldn’t be too bad, after all, the issue would appear itself as a runaway trim and there’s a procedure for that, and it has been around for 5 decades. Shouldn’t be too difficult for pilots already typed in the aircraft, right? Well they under looked these third world countries and the training issues they have. Oops. And it’s not like the system in Airbus aircraft, ya know? Like the one where the crews gotta call to the ground team to figure out what’s going on, who’s hiding systems? Airbus has been dealing with the same and has already been told by both US and Europe to fix it, but haven’t. So while everyone expects Boeing to fix this issue in under a year, Airbus hasn’t fixed theirs, in over 10 years now. Could it be, that designing an aircraft is just difficult? Nah, totally easy. Anyone can do it and Boeing should have knew better. It’s not like airlines had the option to purchase a second sensor but chose not to, and how did the airlines know to buy one or two? The 737 has always looked at one sensor the same way the Max did. It was just based off whoever was flying the plane.

It’s not like the Brazilian authority has MCAS on paper and listed as “B” training from January 2018. Besides all of that, the runaway stabilizer procedure has been the same and hardly changes. As you guys probably already know, the procedure that will disable MCAS. And Ethiopias crew knew it, because they verbalized it, and did it, and undid it. Then accelerated beyond the design limit and crashed. Blame Boeing. If anything, we can say Lions crew had the harder battle due to them not “knowing” not considering the fact that it literally the same as a runaway stab malfunction. Ethiopias crew was already reminded of the issue, due to the Lion crash. Boeing highlighted the issues on the checklist. And sent it out. It’s important that airlines inform their pilots of the new changes

That say “In the event of an uncommanded nose pitch down, hit the stab trim cut out switches to CUTOFF and stay in the CUTOUT position for remainder of flight” yet Ethiopias crew battled with the entire issue until it was near full nose down, then they cut out the switches. They also skipped over step 2 which was too disengage auto throttles, and that allowed the aircraft to fly to and past VMO and out of the flights envelope. Increasing nose down trim and increasing airspeed will result in a stronger nose down force. It’s also clear that when the FO took control, after hitting the cut out switches, he trimmed in the WRONG DIRECTION. And told his captain “it’s not working” followed by his captain saying “pitch up with me”

One of them re engaged the stab trim switches, and that allowed MCAS to reactivate and drive the nose down back down, and it did. Despite them knowing what was going on, and the entire procedure, and lions crash, they still failed the aircraft. I’m not trying to be harsh, but the blame is all going on Boeing when it shouldn’t. It’s clear there’s enough blame to around here. And allowing such training issues to go unnoticed is going to be a disaster for the aviation industry.


You seem very eager to point the blame at the pilots and cite deficient training and lack of experience (hours) amongst crews at airlines operating in 3rd world countries while seemingly casting aside any culpability on Boeing’s end.

My understanding is that there are a plethora of 3rd world airlines operating the 737NG , 32x CEO and 32x NEO in their fleets. How many instances can you cite where a 737NG, or 32x, operated by a 3rd world airline was turned into a lawn dart ? How do you suppose these 3rd world crews can safely operate thousands of NGs, CEOs and NEOs everyday but somehow they managed to plow 2 MAXs into the ground within half a years time ?

If poor training and lack of experience amongst 3rd world crew members is as big of a problem as you seem to claim, isn’t it reasonable to expect we would see higher numbers of catastrophic hull losses from other variants operated by these airlines. 3rd world airlines have massive fleets of 32x NEOs in their fleets. Given your stance, I assume you feel the NEO is 3rd world pilot proof given there hasn’t been a single hull loss, and thusly a superior aircraft ?

And before you go off citing Lion Air’s runway excursion incidents and attributing that to their status as a 3rd world airline you really ought to consider WN is usually good for an excursion or 2 every year. Beyond that, they have 2 very high profile runway excursions in their history (BUR/MDW). DL had a rather violent one at LGA a few years back too. I suppose you consider WN and DL 3rd world ?

Moreover, I could cite a number of US airlines that have had accidents/incidents, some resulting in fatalities due to poor maintenance. Again at the forefront of my mind is WN. To use your own examples, correct me if I’m wrong but wasn’t it an improperly installed fan blade on UA232 that ultimately led to the crash? AQ243 had metal fatigue so extreme that a passenger noticed a crack prior to take off that ultimately led to the top of the fuselage peeling back. If a passenger noticed such wear and tear certainly the maintenance team should have. I guess we can add United and the now defunct Aloha to the list of 3rd world airlines.

Almost forgot, you brought up questionable professional conduct by crews of 3rd world airlines to, citing drug charges was it ? I seem to recall several threads just this year regarding several US crews being arrested at the airport attempting to board their aircraft intoxicated... Oh and let’s not such professional conduct like the US crew that overflew their destination by approximately 150 miles or another that landed at the wrong airport.

Speaking candidly your posts sound quite ignorant.

77H



Lol, except the fact that shady shit goes unnoticed a lot longer in those countries than they do here.

3rd world or not, crashes happen, and yes there are accidents here in the US and Europe, but do we see accidents from failing a basic procedure like the one presented? No. You never would. Fact. Would European or American crews forget throttles in full? No. Would they not only leave throttle at full, but try to manually trim the aircraft like that? No. Would they fly out of the envelope and still try to manually trim? No. Would the F/O trim in the wrong direction? No. Would either reverse a procedure that’s been well known to never reverse? No. These accident crews performed extremely Hmmmm horribly, and as pilots we have the job to ensure a safe outcome for the flight. In some cases, it can be understandable. It is not understandable in the slightest form here. Some people forget what it takes to become a pilot, or the importance of having reliable, and trained pilots. It’s almost like you guys are okay with the ways these airlines train their pilots. You put either accident crew in UA232 position, guess what? Everyone is dead. Gone. You put the pilots in JT610 position. Landed. You put the pilots of UA232 in ET302 position, landed. Fact.


And a plane should not put the pilots in a dangerous situation due to a design error. Fact. Or does first world training and skill standards not apply to engineers and managers at Boeing?
 
77H
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Sat Nov 16, 2019 11:25 am

Nick1209 wrote:
77H wrote:
Nick1209 wrote:
Hoping and Relying on the ECAA won’t do much. Just look what those goons did with EgyptAir 990. Are we really expecting them to come up with an actual conclusion? They’re probably looking for dirt on Boeing far more than investigating the accident.

There’s a reason why Lion Air rushed to the families after the incident, and forced them to sign papers agreeing not to sue them, nor Boeing. They simply didn’t wanna ruin their relationship with Boeing over something their pilots should have known. Like not selling them anymore aircraft till they prove otherwise. All the talk from airlines regarding the max is just politics. I remember what the CEO for United said right after the incident too lol.

If we wanted to make sure every plane was perfectly built, then we would be grounding every single one. I can’t even begin to tell you how many aircraft have been cleared to fly that have “design flaws” but haven’t affected a single flight today. Not even Boeing’s “design flaw” affected either accident. It wasn’t the engines that caused the plane to crash. They both had a software malfunction. Which is Impossible to prevent. And any malfunction that is improperly handled, will end up the same way. Both of which were handled improperly. To me, this is more important that what happened at Boeing because even a perfectly designed and certified airplane can have failures and the crews are the ones who are left to handle them. Crews must be prepared to handle whatever emergency we are presented with, even those like UAL232, Aloha 243, Qantas 32, Qantas 72, and SWA1380 which were failures that were never anticipated and for which no crew had ever been trained.

So how much longer are we going to act like the crashes were very controllable, and entirely preventable? Of which happened in third world countries andone FO with a low amount of hours, flying the plane.

Regardless, neither crew completed a single step on their procedures for runaway stabilizer OR unreliable airspeed. Both of which have to be done in a reasonably manner to prevent an accident.

Lions crew knew what procedure to follow, but forgot it. As you can see on the final report. What I wanted to know, was why did the Captain keep them in trim through 21 MCAS activations, but the FO, to whom took control, did not. Neither of them went to their procedure. We know why though, now. Because they forgot it. Sounds like Lion Air if you ask me, just how many times have their pilots missed the runway, and confused the ocean for the runway? And how many drug charges have been in the news for their pilots?

Let’s not forget that Boeing promised the Max would come without any additional training. And the issues with the engine position was nonexistent till the end of certification. It wasn’t until the stick force per g, which involves banking the aircraft and pulling back on the yoke, and of course banking more and pulling back more, it should be harder to pull back each time, and never easier. But because of Boeing’s engine positioning, an aerodynamic nose up appeared. This nose up created a feeling of it being easier to pull back. The aircraft didn’t Meet FAA longitudinal stability anymore. So the easiest fix was to add some nose down. So it’s quite comical to watch the media call it a “stall prevention system” which is far from true. Just because Airbus has one, and calls it that, and yes, they’ve killed people with their system as well, but doesn’t mean it’s the same for Boeing. Their products do not need a stall prevention system nor recovery system. They’ll recover a stall with the control column in neutral.

Boeing figured one sensor shouldn’t be too bad, after all, the issue would appear itself as a runaway trim and there’s a procedure for that, and it has been around for 5 decades. Shouldn’t be too difficult for pilots already typed in the aircraft, right? Well they under looked these third world countries and the training issues they have. Oops. And it’s not like the system in Airbus aircraft, ya know? Like the one where the crews gotta call to the ground team to figure out what’s going on, who’s hiding systems? Airbus has been dealing with the same and has already been told by both US and Europe to fix it, but haven’t. So while everyone expects Boeing to fix this issue in under a year, Airbus hasn’t fixed theirs, in over 10 years now. Could it be, that designing an aircraft is just difficult? Nah, totally easy. Anyone can do it and Boeing should have knew better. It’s not like airlines had the option to purchase a second sensor but chose not to, and how did the airlines know to buy one or two? The 737 has always looked at one sensor the same way the Max did. It was just based off whoever was flying the plane.

It’s not like the Brazilian authority has MCAS on paper and listed as “B” training from January 2018. Besides all of that, the runaway stabilizer procedure has been the same and hardly changes. As you guys probably already know, the procedure that will disable MCAS. And Ethiopias crew knew it, because they verbalized it, and did it, and undid it. Then accelerated beyond the design limit and crashed. Blame Boeing. If anything, we can say Lions crew had the harder battle due to them not “knowing” not considering the fact that it literally the same as a runaway stab malfunction. Ethiopias crew was already reminded of the issue, due to the Lion crash. Boeing highlighted the issues on the checklist. And sent it out. It’s important that airlines inform their pilots of the new changes

That say “In the event of an uncommanded nose pitch down, hit the stab trim cut out switches to CUTOFF and stay in the CUTOUT position for remainder of flight” yet Ethiopias crew battled with the entire issue until it was near full nose down, then they cut out the switches. They also skipped over step 2 which was too disengage auto throttles, and that allowed the aircraft to fly to and past VMO and out of the flights envelope. Increasing nose down trim and increasing airspeed will result in a stronger nose down force. It’s also clear that when the FO took control, after hitting the cut out switches, he trimmed in the WRONG DIRECTION. And told his captain “it’s not working” followed by his captain saying “pitch up with me”

One of them re engaged the stab trim switches, and that allowed MCAS to reactivate and drive the nose down back down, and it did. Despite them knowing what was going on, and the entire procedure, and lions crash, they still failed the aircraft. I’m not trying to be harsh, but the blame is all going on Boeing when it shouldn’t. It’s clear there’s enough blame to around here. And allowing such training issues to go unnoticed is going to be a disaster for the aviation industry.


You seem very eager to point the blame at the pilots and cite deficient training and lack of experience (hours) amongst crews at airlines operating in 3rd world countries while seemingly casting aside any culpability on Boeing’s end.

My understanding is that there are a plethora of 3rd world airlines operating the 737NG , 32x CEO and 32x NEO in their fleets. How many instances can you cite where a 737NG, or 32x, operated by a 3rd world airline was turned into a lawn dart ? How do you suppose these 3rd world crews can safely operate thousands of NGs, CEOs and NEOs everyday but somehow they managed to plow 2 MAXs into the ground within half a years time ?

If poor training and lack of experience amongst 3rd world crew members is as big of a problem as you seem to claim, isn’t it reasonable to expect we would see higher numbers of catastrophic hull losses from other variants operated by these airlines. 3rd world airlines have massive fleets of 32x NEOs in their fleets. Given your stance, I assume you feel the NEO is 3rd world pilot proof given there hasn’t been a single hull loss, and thusly a superior aircraft ?

And before you go off citing Lion Air’s runway excursion incidents and attributing that to their status as a 3rd world airline you really ought to consider WN is usually good for an excursion or 2 every year. Beyond that, they have 2 very high profile runway excursions in their history (BUR/MDW). DL had a rather violent one at LGA a few years back too. I suppose you consider WN and DL 3rd world ?

Moreover, I could cite a number of US airlines that have had accidents/incidents, some resulting in fatalities due to poor maintenance. Again at the forefront of my mind is WN. To use your own examples, correct me if I’m wrong but wasn’t it an improperly installed fan blade on UA232 that ultimately led to the crash? AQ243 had metal fatigue so extreme that a passenger noticed a crack prior to take off that ultimately led to the top of the fuselage peeling back. If a passenger noticed such wear and tear certainly the maintenance team should have. I guess we can add United and the now defunct Aloha to the list of 3rd world airlines.

Almost forgot, you brought up questionable professional conduct by crews of 3rd world airlines to, citing drug charges was it ? I seem to recall several threads just this year regarding several US crews being arrested at the airport attempting to board their aircraft intoxicated... Oh and let’s not such professional conduct like the US crew that overflew their destination by approximately 150 miles or another that landed at the wrong airport.

Speaking candidly your posts sound quite ignorant.

77H



Lol, except the fact that shady shit goes unnoticed a lot longer in those countries than they do here.

3rd world or not, crashes happen, and yes there are accidents here in the US and Europe, but do we see accidents from failing a basic procedure like the one presented? No. You never would. Fact. Would European or American crews forget throttles in full? No. Would they not only leave throttle at full, but try to manually trim the aircraft like that? No. Would they fly out of the envelope and still try to manually trim? No. Would the F/O trim in the wrong direction? No. Would either reverse a procedure that’s been well known to never reverse? No. These accident crews performed extremely Hmmmm horribly, and as pilots we have the job to ensure a safe outcome for the flight. In some cases, it can be understandable. It is not understandable in the slightest form here. Some people forget what it takes to become a pilot, or the importance of having reliable, and trained pilots. It’s almost like you guys are okay with the ways these airlines train their pilots. You put either accident crew in UA232 position, guess what? Everyone is dead. Gone. You put the pilots in JT610 position. Landed. You put the pilots of UA232 in ET302 position, landed. Fact.


Is it a fact that “shady shit” goes unnoticed longer in 3rd world countries than in the US or Europe?
That’s rich considering this entire thread revolves around “shady shit” Boeing did during certification. Not to mention the recent revelation about the US MRO that installed the AoA sensor on the Lion Air MAX. For nearly a decade XTRA was egregiously out of compliance and the worse still, the FAA was none the wiser during that time period.

Not to mention all the whistleblower allegations regarding quality control on the 787.

77H
 
AABusDrvr
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Sat Nov 16, 2019 11:28 am

Nick1209 wrote:
B777LRF wrote:
Nick1209 wrote:
I believe it’s a business tactic pure and simple. The military doesn’t care how much they spend in the end. Airlines do. Airlines didn’t buy the second sensor although they had a choice to, for a reason. And Boeing knew it wouldn’t go over well with them, as shown, because in the end they didn’t purchase the sensor.


I'm not sure if it's a tactic or blatant arrogance, but the latter part of your argument is not a true representation. There was no option to buy a second sensor; there was an option to buy an AoA indicator. There was also an option to buy an AoA disagree warning, which was taken up by at least Southwest. Problem was, it didn't work because there was no independent box to compare the signals from both AoA sensors, and the FCC ran on the signal from only one of them. Nice one.


Southwest doesn’t have it. Nor any airline in the US. Only one does and it’s none of them.

The 737 has always looked at AoA sensors the same way the max does. Simultaneously. Whatever side the flying pilot is on, and then vice versa once the other takes control.


IIRC on the NG, the AOA disagree comparator came with the optional AOA indicators. American Airlines has always had the optional AOA indicators/AOA disagree comparator warning in their 737's, all the way back to the first NG. The software problems with the MAX display system was why the AOA disagree wasn't working on the MAX, even with the AOA indicators.
 
sharpley
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Sat Nov 16, 2019 12:16 pm

Nick1209 wrote:
You put either accident crew in UA232 position, guess what? Everyone is dead. Gone. You put the pilots in JT610 position. Landed. You put the pilots of UA232 in ET302 position, landed. Fact.

Not fact at all. You can assume that, but its something we'll never know.
 
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PixelFlight
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Sat Nov 16, 2019 12:54 pm

Nick1209 wrote:
You put either accident crew in UA232 position, guess what? Everyone is dead. Gone. You put the [UA232] pilots in JT610 position. Landed. You put the pilots of UA232 in ET302 position, landed. Fact.
:crazy: This is only 3 consecutive speculations, not facts at all.

The fact is that no aircraft safety agencies want to asses the aircraft safety based on speculations. The facts there have in hands is a flawed safety assessment on the 737-7/8/9 MAX directly liked to the two last deadliest crashes records, and a worldwide historically low fatal crash rate per year, especially without the flawed 737-8 MAX. The 737-7/8/9 MAX need to be fixed. The worldwide training need to be improved. But don't try to mix the two subjects, there have different causes and have different fixes. As the EASA said: "Pilot training requirements are not meant to compensate for non-acceptable design on the compliance and safety standpoint."
: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:
 
CobaltScar
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Sat Nov 16, 2019 2:35 pm

The longer this gets delayed (now its looking like March at earliest?) the greater the chances a all 737 fleet like SWA will be forced to consider acquiring another airline with airbus. If it gets delayed past March I don't see how SWA can sit on their hands without making a bold move.
 
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Revelation
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Sat Nov 16, 2019 2:56 pm

maint123 wrote:
And has anyone categorically said what will happen to the aerodynamics of max if MCAS is removed or stopped in flight ? Do pilots really need the help from mcas ? Basically if the Max can fly OK without mcas , why keep a potentialy disaster prone system?

We do know nacelle lift at high AoA makes the stick feel lighter as the aircraft gets closer to the stall, and we know decades of aviation regulations have made it so such a phenomena does not happen on certified aircraft. Changing that pattern feels like it could be pretty problematic, no? Best to follow the regs with exemptions as allowed and of course properly design, implement, test, train and document the feature as well.
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Revelation
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Sat Nov 16, 2019 3:18 pm

CobaltScar wrote:
The longer this gets delayed (now its looking like March at earliest?) the greater the chances a all 737 fleet like SWA will be forced to consider acquiring another airline with airbus. If it gets delayed past March I don't see how SWA can sit on their hands without making a bold move.

If WN decided to add Airbus today, consider how long it would take to:
* gain delivery of product
* produce required crew and maintenance training regimes
* buy and install necessary training sims, spare parts, tools, etc
* train crew and maintenance staff to that new regime
* negotiate new pay rates for unionized staff for new equipment
* add aircraft to needed IT systems
* get approval to add aircraft to AOC

It'd take a lot longer than March to do all of the above.

I think you may be reading too much into one statement by an angry SWAPA union representative.

If they wanted to make a "bold move" in a timely fashion the best they could do was arrange a wet lease, but that would piss off the union representative even more.

Management of course must perform due diligence to understand what adding fleet diversity would mean, but it's hard to see the numbers working out.

The only thing that could make such an addition happen is if WN senior management felt the had to make a bold move regardless of cost, and we have no evidence that they have resolved to do so.
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maint123
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Sat Nov 16, 2019 3:19 pm

Revelation wrote:
maint123 wrote:
And has anyone categorically said what will happen to the aerodynamics of max if MCAS is removed or stopped in flight ? Do pilots really need the help from mcas ? Basically if the Max can fly OK without mcas , why keep a potentialy disaster prone system?

We do know nacelle lift at high AoA makes the stick feel lighter as the aircraft gets closer to the stall, and we know decades of aviation regulations have made it so such a phenomena does not happen on certified aircraft. Changing that pattern feels like it could be pretty problematic, no? Best to follow the regs with exemptions as allowed and of course properly design, implement, test, train and document the feature as well.

Just thinking out loud, regarding the max, at take off the auto pilot is off, so mcas is in play.
Now if the AOA sensor is damaged /malfunctions during take off, MCAS again pushes the nose down, but now the pilots get a warning of mismatched AOA inputs from the 2nd sensor, so ignore the AOA input and start trimming like in the lion air crash. And now the modified MCAS does not push the nose down repeatedly since AOA is manually/automatically confirmed to be faulty.
So in this case the plane is basically flying in manual mode with no MCAS, just like the NG, while climbing. The difference being the plane's different aerodynamics will force the pilot to keep making some inputs to counteract the pitch up tendency? And the late changes made to increase the MCAS authority from 0.6 to 2.5 deg, indicates that a lot of manual input will be required from the pilots.
Will be interesting.
 
shmerik
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Sun Nov 17, 2019 5:55 am

maint123 wrote:
Revelation wrote:
maint123 wrote:
And has anyone categorically said what will happen to the aerodynamics of max if MCAS is removed or stopped in flight ? Do pilots really need the help from mcas ? Basically if the Max can fly OK without mcas , why keep a potentialy disaster prone system?

We do know nacelle lift at high AoA makes the stick feel lighter as the aircraft gets closer to the stall, and we know decades of aviation regulations have made it so such a phenomena does not happen on certified aircraft. Changing that pattern feels like it could be pretty problematic, no? Best to follow the regs with exemptions as allowed and of course properly design, implement, test, train and document the feature as well.

Just thinking out loud, regarding the max, at take off the auto pilot is off, so mcas is in play.
Now if the AOA sensor is damaged /malfunctions during take off, MCAS again pushes the nose down, but now the pilots get a warning of mismatched AOA inputs from the 2nd sensor, so ignore the AOA input and start trimming like in the lion air crash. And now the modified MCAS does not push the nose down repeatedly since AOA is manually/automatically confirmed to be faulty.
So in this case the plane is basically flying in manual mode with no MCAS, just like the NG, while climbing. The difference being the plane's different aerodynamics will force the pilot to keep making some inputs to counteract the pitch up tendency? And the late changes made to increase the MCAS authority from 0.6 to 2.5 deg, indicates that a lot of manual input will be required from the pilots.
Will be interesting.


For me these two points suggest that the lift is more extreme than Boeing is letting on:

1) The extreme increase in MCAS authority
2) Not disclosing the actual extent of the nacelle lift

It seems like Boeing could easily make everyone feel much more comfortable if they would simply release some info about what they found about the increased amount of lift. If it's really a "slight lightening of the controls" (one quote I remember reading was that you would barely notice if you weren't actually looking for it) then wouldn't it be a no brainer to release some actual test data and allay everyone's fears? That would immediately show that the airframe itself is pretty much as safe as others and that MCAS was really just needed in order to comply with regulations.

The facts that Boeing is telling as little as possible at every step of the way and that the authority of MCAS was increased ~4x it's original implementation makes it seem like what they discovered was much worse than the minor issue they make it out to be.
 
kalvado
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Sun Nov 17, 2019 10:15 am

shmerik wrote:
maint123 wrote:
Revelation wrote:
We do know nacelle lift at high AoA makes the stick feel lighter as the aircraft gets closer to the stall, and we know decades of aviation regulations have made it so such a phenomena does not happen on certified aircraft. Changing that pattern feels like it could be pretty problematic, no? Best to follow the regs with exemptions as allowed and of course properly design, implement, test, train and document the feature as well.

Just thinking out loud, regarding the max, at take off the auto pilot is off, so mcas is in play.
Now if the AOA sensor is damaged /malfunctions during take off, MCAS again pushes the nose down, but now the pilots get a warning of mismatched AOA inputs from the 2nd sensor, so ignore the AOA input and start trimming like in the lion air crash. And now the modified MCAS does not push the nose down repeatedly since AOA is manually/automatically confirmed to be faulty.
So in this case the plane is basically flying in manual mode with no MCAS, just like the NG, while climbing. The difference being the plane's different aerodynamics will force the pilot to keep making some inputs to counteract the pitch up tendency? And the late changes made to increase the MCAS authority from 0.6 to 2.5 deg, indicates that a lot of manual input will be required from the pilots.
Will be interesting.


For me these two points suggest that the lift is more extreme than Boeing is letting on:

1) The extreme increase in MCAS authority
2) Not disclosing the actual extent of the nacelle lift

It seems like Boeing could easily make everyone feel much more comfortable if they would simply release some info about what they found about the increased amount of lift. If it's really a "slight lightening of the controls" (one quote I remember reading was that you would barely notice if you weren't actually looking for it) then wouldn't it be a no brainer to release some actual test data and allay everyone's fears? That would immediately show that the airframe itself is pretty much as safe as others and that MCAS was really just needed in order to comply with regulations.

The facts that Boeing is telling as little as possible at every step of the way and that the authority of MCAS was increased ~4x it's original implementation makes it seem like what they discovered was much worse than the minor issue they make it out to be.

We're talking about a company which have chosen to redact list of hot and high US airports from the public version of document in A220 tariff case.
Even if "some lightening" statement is an honest one - which is extremely hard to believe - even "engine lift" part of discussion is a third party speculation not confirmed by Boeing.
Overall, I really hope EASA gets there MCAS-off flight, and I pray that they don't crash. That would put a hard end to many things....
 
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Revelation
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Re: Boeing 737MAX Grounded Worldwide Q4 2019

Sun Nov 17, 2019 2:09 pm

shmerik wrote:
For me these two points suggest that the lift is more extreme than Boeing is letting on:

1) The extreme increase in MCAS authority
2) Not disclosing the actual extent of the nacelle lift

It seems like Boeing could easily make everyone feel much more comfortable if they would simply release some info about what they found about the increased amount of lift. If it's really a "slight lightening of the controls" (one quote I remember reading was that you would barely notice if you weren't actually looking for it) then wouldn't it be a no brainer to release some actual test data and allay everyone's fears? That would immediately show that the airframe itself is pretty much as safe as others and that MCAS was really just needed in order to comply with regulations.

The facts that Boeing is telling as little as possible at every step of the way and that the authority of MCAS was increased ~4x it's original implementation makes it seem like what they discovered was much worse than the minor issue they make it out to be.

The counter to "Boeing is saying very little because they have something to hide" is "Boeing is saying very little because for MAX right now less news is better than more news".

I think Boeing has been saying little over the last few weeks because they realize anything they say starts a new news cycle and it's best for them to stay out of the news till they have good news to report.

If they did some elaborate presentation on nacelle lift and stick force not being significant some tech savvy people would feel better about the state of affairs, but some non tech savvy people will start to worry about nacelle lift and stick force and stalling and falling out of the sky pretty much every time they get on a Boeing product.

Given Boeing's reputation is much more damaged than FAA's reputation, Boeing is going to keep mostly quiet till FAA approves return to flight, then start putting out pressers about about how safe flying is versus driving, decades of improvements in safety, etc.
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