Various news outlets reporting the Joint Committee will convene on Tuesday for 90 days. Would tend to support a target to roll-out the fix around end July.

Ray

XRAYretired wrote:

Various news outlets reporting the Joint Committee will convene on Tuesday for 90 days. Would tend to support a target to roll-out the fix around end July.

Ray

Sorry to ask if it has been explained earlier, but what authority does this "Joint Committee" have? Does it have the authority to un-ground the plane worldwide?

With immediate effect? By all agencies?

Interested wrote:

Zeppi wrote:

Interesting summary on Boeing's corporate culture and cost/corner cutting by a former employee https://old.reddit.com/r/videos/comments/bdfqm4/the_real_reason_boeings_new_plane_crashed_twice/ekyyd9g/.
Of course no way to verify, just thought it would fit into this topic as more an more evidence seems to point this way.

Looks like the old slogan needs some rework too: If it's Boeing, I ain't going.

Such a shame that a company that used to be held high by producing quality aircraft seems to have deteriorated into yet another case of corporate greed taking over.

It's too detailed to be made up

It's not a reflection of Boeing it's a reflection or large organisations full stop

It isn't too detailed to be made up. In fact, the more detailed the more likely it is made up. One thing large corporations don't do is hire people they don't need. They are more likely to lay people off that they do need.

Why hasn't the engineer he refers to being exiled leaked info to the media? If he was near retirement in 2008 he is certainly retired by now.

Anonymous posts on Reddit are not likely to be the truth. The only anonymous reports that can be trusted are unnamed sources used by real journalists that vet the information because they are risking their career and reputation if they print things that are made up.

Just because it fits your opinion that Boeing is evil and cutting corners on safety for profit doesn't make it true.

The stuff about the 787 is garbage. They made modifications and design changes based on structural testing. They didn't sell planes with inadequate structure. The only thing wrong with the early production examples that were sold is they are heavier. I haven't seen the news about any of the 1441 787s falling apart. The only major problems with the 787 are related to the engines, mostly from RR.

sassiciai wrote:

XRAYretired wrote:

Various news outlets reporting the Joint Committee will convene on Tuesday for 90 days. Would tend to support a target to roll-out the fix around end July.

Ray

Sorry to ask if it has been explained earlier, but what authority does this "Joint Committee" have? Does it have the authority to un-ground the plane worldwide?

With immediate effect? By all agencies?

Protocols have not been published as far as I know. As to authority? none? Could its conclusions be ignored - emphatically not I would suggest.

Ray

planecane wrote:

Interested wrote:

Zeppi wrote:

Interesting summary on Boeing's corporate culture and cost/corner cutting by a former employee https://old.reddit.com/r/videos/comments/bdfqm4/the_real_reason_boeings_new_plane_crashed_twice/ekyyd9g/.
Of course no way to verify, just thought it would fit into this topic as more an more evidence seems to point this way.

Looks like the old slogan needs some rework too: If it's Boeing, I ain't going.

Such a shame that a company that used to be held high by producing quality aircraft seems to have deteriorated into yet another case of corporate greed taking over.

It's too detailed to be made up

It's not a reflection of Boeing it's a reflection or large organisations full stop

It isn't too detailed to be made up. In fact, the more detailed the more likely it is made up. One thing large corporations don't do is hire people they don't need. They are more likely to lay people off that they do need.

Why hasn't the engineer he refers to being exiled leaked info to the media? If he was near retirement in 2008 he is certainly retired by now.

Anonymous posts on Reddit are not likely to be the truth. The only anonymous reports that can be trusted are unnamed sources used by real journalists that vet the information because they are risking their career and reputation if they print things that are made up.

Just because it fits your opinion that Boeing is evil and cutting corners on safety for profit doesn't make it true.

The stuff about the 787 is garbage. They made modifications and design changes based on structural testing. They didn't sell planes with inadequate structure. The only thing wrong with the early production examples that were sold is they are heavier. I haven't seen the news about any of the 1441 787s falling apart. The only major problems with the 787 are related to the engines, mostly from RR.

So you believe someone just imagined all of that?

And wrote a made up story that long? Why would they? What's the point?

XRAYretired wrote:

sassiciai wrote:

XRAYretired wrote:

Various news outlets reporting the Joint Committee will convene on Tuesday for 90 days. Would tend to support a target to roll-out the fix around end July.

Ray

Sorry to ask if it has been explained earlier, but what authority does this "Joint Committee" have? Does it have the authority to un-ground the plane worldwide?

With immediate effect? By all agencies?

Protocols have not been published as far as I know. As to authority? none? Could its conclusions be ignored - emphatically not I would suggest.

Ray

I guess the first challenge with so many involved is for them all to agree on something !!

A bitter former employee/ You can find those at every company.

zeke wrote:

OldAeroGuy wrote:

The MAX may have less stability near stall than needed to meet the stall handling certification requirements, but it is not unstable. As I have said previously, the MAX is not the first airplane to require "fixing" in this region. A wFBW airplane may have a similar solution to MCAS in "Normal" mode that the pilot is entirely unaware of.

If Boeing had fitted MCAS.v2 originally, I doubt that we'd be talking about it today.

The main difference between non FBW and FBW in these situations to me is the feedback loop in the FBW system, FBW would stop control changes when the desired output is achieved. The 737 is very mechanical, if a condition is met, an output continues to be generated like MCAS does.

I have talked to some other 737 pilots as to what else could have been going through the crews minds. They have told me that a blocked static port will also present some of the same symptoms as what these pilots saw, split air speeds, inaccurate altitude, stick shaker, and even wind shear warning. Also mentioned to me that a broken AOA on the NG can cause the elevator feel shift module (EFSM) to increase the control column feel 4 times as it triggers at 11 degrees. So unless this was changed on the MAX, they would have to counter the extra control column force generated by the EFSM in addition to the MCAS changes.

You both touched the very essential concept of choosing an augmentation/automation/protection system.

There is the "fix issue" approach: identify the situations where an improvement is required and design a specialized system that detect predefined conditions of that situation and generate discrete commands to augment the characteristics. The consequence is an increase of specialized systems with each there own failure mode. The pilots need to understand each of them and to be trained to overcome any possible failure modes in addition to decide to land quickly if required. This approach have no future in new design. It exists only because this was the only technology available at some point in the past.

There is the "keep safe" approach: define the mathematical model of the characteristics, bound the safe domain for protection, and compute the safest attitude in real time. Only possible on FBW aircraft with appropriate computers resources and enough reliable sensors data. The availability of reliable sensors data define the capabilities of the model, refereed as laws. Pilots need to understands a few laws and to be trained how to fly in each of them in addition to decide to land quickly if required. This approach is the actual standard for new design since about 3 decades.

There is the "predictive" approach: define the mathematical predictive filter of all the inputs from all the outputs and compute the probabilities of the safest attitudes in real time. Only possible on highly connected information system like AFDX aircraft with appropriate computers resources. The sensors data quality will define in real time the protection domain and the safest attitude. The pilots need to understand how the quality of the sensors data affect the safety of the flight to decide to land quickly if required. This approach will be the future for new design, I hope in less than a decade.

There is the "learning" approach: let the AI adjust the model in real time and evaluate the safety of the flight. The AI will decide to land quickly if required and will do it. Pilots need to understand the limitation of the AI and to be trained to communicate relevant information with it. This approach will be introduced in aircraft when this technology will be perceived by the public as the safest in a world where a large amount of systems will already be autonomous and safe. Sound like a fiction to many today, but there are peoples working on that direction. No idea when it will be introduced.

There is the "consciousness" approach: the AI is communicating with ATC (or whatever that replace his function) and each PAX in addition to every possible relevant information systems on the planet. AI is the pilot. Today technologies and researches have no identified path to make this, but as the human brain already do that, we know this is possible.

XRAYretired wrote:

sassiciai wrote:

XRAYretired wrote:

Various news outlets reporting the Joint Committee will convene on Tuesday for 90 days. Would tend to support a target to roll-out the fix around end July.

Ray

Sorry to ask if it has been explained earlier, but what authority does this "Joint Committee" have? Does it have the authority to un-ground the plane worldwide?

With immediate effect? By all agencies?

Protocols have not been published as far as I know. As to authority? none? Could its conclusions be ignored - emphatically not I would suggest.

Ray

I would hope this is about a return to flight based on trust, not on authority. With an independent review, and possibly changes based on such a review, there is no reason to keep grounding in place - especially for those nations who are part of such review.
Much better approach than threats...

ArgentoSystems wrote:

planecane wrote:

If a house is burning down the firefighters put it out the same way. They don't need training based on if it started from an electrical overload or a candle falling over.

Not exactly correct. You use different types of fire-extinguishers for different fires. You don't put water on electrical fire, for example. Chemical fires is a different matter altogether. So yeah, they do need training to handle different type of fires.

Actually, in the context of a house fire ignited by electricity, you turn off the electricity and put water on it. Electricity doesn't burn, it heats stuff that burns.

In the case of burning liquids, you use a class B agent. The key is "class B", meaning that for a class of fire types, you use a class of agent, not a specific one. Oh sure, there are different brands/types that may be better/worse, but that is often marketing.

The analogy works. For runaway stab, you do runaway stab procedure.

The problem with mcas in the accident flights in my moderately informed opinion, was two fold. It was part of a cascading failure, which presented the pilots with multiple symptoms at relatively low altitude, confusing them, and it was too aggressive.

The first you address but increasing the robustness of the system that caused stab runnaway, the second you address but limiting system authority. The changes Boeing is making do both of those.

Now, should Boeing have done that initially? In a 20/20 hindsight world, that seems obvious. But, before the crashes, the argument that

"1) MCAS is not often used,
2) that if it fails, it is just a runaway stab trim which pilots already know how to deal with,

is not unreasonable.

Unfortunately, it seems no engineer had the imagination to ask,

"What if this thing fails during takeoff because of a left side aoa failure that causes a false high angle of attack and also causes concurrent stall warnings and stick shaker and unreliable airspeed, and it keeps trying to trim down hard, and confuses the crew, who may or may not be stellar pilots. Is that a problem?"

The answer to that question is, as we now know, yes it may be. (Not unqualified yes, because some crews managed it, but definitely a potential yes.). But it seems that the question was not asked, or if it was the answer was wrong.

And, no, I'm not being facetious here. The question to be asked is not simple. Also, as humans, we are subject to biases, probably confirmation bias played a role here.

What I don't believe is that Boeing engineers purposefully ignored and hid a fatal flaw. I'm less confident in management, but I've seen no evidence of malice at either Boeing of the faa. Errors, yes, malice no. If we do find malice, then we act. And perhaps we investigate.

But I believe this was an error, a serious one with deadly consequences, but an error. Not the first, in aviation, and unfortunately, not likely the last.

Interested wrote:

planecane wrote:

Interested wrote:

It's too detailed to be made up

It's not a reflection of Boeing it's a reflection or large organisations full stop

It isn't too detailed to be made up. In fact, the more detailed the more likely it is made up. One thing large corporations don't do is hire people they don't need. They are more likely to lay people off that they do need.

Why hasn't the engineer he refers to being exiled leaked info to the media? If he was near retirement in 2008 he is certainly retired by now.

Anonymous posts on Reddit are not likely to be the truth. The only anonymous reports that can be trusted are unnamed sources used by real journalists that vet the information because they are risking their career and reputation if they print things that are made up.

Just because it fits your opinion that Boeing is evil and cutting corners on safety for profit doesn't make it true.

The stuff about the 787 is garbage. They made modifications and design changes based on structural testing. They didn't sell planes with inadequate structure. The only thing wrong with the early production examples that were sold is they are heavier. I haven't seen the news about any of the 1441 787s falling apart. The only major problems with the 787 are related to the engines, mostly from RR.

So you believe someone just imagined all of that?

And wrote a made up story that long? Why would they? What's the point?

The point? Some people like attention and get it by posting things like that.

The poster probably did briefly work for Boeing. I'm sure as in ALL corporate environments there were lazy engineers goofing off at work. There is probably a higher percentage at Boeing due to the engineers being unionized.

I'm sure there was some crusty old engineer always gossiping like he is the be all, end all expert on everything on the company. Every engineering department has someone like that.

So the guy takes some facts and embellishes to fit a narrative that people with your opinions eat up to get "likes" on a Reddit post and feel good about himself. He likely got fired or laid off and saw this post as a way to get some revenge on his former employer.

Like I said, there are things he states about the 787 that are not true. It makes absolutely no sense that Boeing would spend the time and money to fix the wing rib shear tie issue but just ignore some other structural issue.

The whole MAX issue is a few bad assumptions and decisions, not some kind of corporate culture that a few crashes are ok because we can win a few more sales or make a little more profit.

I still hold my opinion that the failure that led to the ET crash should have been dealt with successfully by the crew. How any MAX crew wouldn't be able to recognize and correct an MCAS induced runaway stabilizer after the Lion Air crash and the EAD is beyond my comprehension. Either they weren't properly educated on the EAD or they couldn't react under pressure.

rcair1 wrote:

Now, should Boeing have done that initially? In a 20/20 hindsight world, that seems obvious. But, before the crashes, the argument that

"1) MCAS is not often used,
2) that if it fails, it is just a runaway stab trim which pilots already know how to deal with,

is not unreasonable.

Unfortunately, it seems no engineer had the imagination to ask,

"What if this thing fails during takeoff because of a left side aoa failure that causes a false high angle of attack and also causes concurrent stall warnings and stick shaker and unreliable airspeed, and it keeps trying to trim down hard, and confuses the crew, who may or may not be stellar pilots. Is that a problem?"

No it is unreasonable argument. First of all, it is an assumption, you don't take it for a fact. Put 10 random crews in a sim, and without any warning present them with a malfunction. See what they do and what they say to you afterwards. It is so easy.

Second, if their lead engineer does not have brains to ask the question at the end of your quote, he should not be leading the project. In fact I would leave entire team without bonuses for being brainless spineless dummies.

planecane wrote:

Interested wrote:

planecane wrote:

It isn't too detailed to be made up. In fact, the more detailed the more likely it is made up. One thing large corporations don't do is hire people they don't need. They are more likely to lay people off that they do need.

Why hasn't the engineer he refers to being exiled leaked info to the media? If he was near retirement in 2008 he is certainly retired by now.

Anonymous posts on Reddit are not likely to be the truth. The only anonymous reports that can be trusted are unnamed sources used by real journalists that vet the information because they are risking their career and reputation if they print things that are made up.

Just because it fits your opinion that Boeing is evil and cutting corners on safety for profit doesn't make it true.

The stuff about the 787 is garbage. They made modifications and design changes based on structural testing. They didn't sell planes with inadequate structure. The only thing wrong with the early production examples that were sold is they are heavier. I haven't seen the news about any of the 1441 787s falling apart. The only major problems with the 787 are related to the engines, mostly from RR.

So you believe someone just imagined all of that?

And wrote a made up story that long? Why would they? What's the point?

The point? Some people like attention and get it by posting things like that.

The poster probably did briefly work for Boeing. I'm sure as in ALL corporate environments there were lazy engineers goofing off at work. There is probably a higher percentage at Boeing due to the engineers being unionized.

I'm sure there was some crusty old engineer always gossiping like he is the be all, end all expert on everything on the company. Every engineering department has someone like that.

So the guy takes some facts and embellishes to fit a narrative that people with your opinions eat up to get "likes" on a Reddit post and feel good about himself. He likely got fired or laid off and saw this post as a way to get some revenge on his former employer.

Like I said, there are things he states about the 787 that are not true. It makes absolutely no sense that Boeing would spend the time and money to fix the wing rib shear tie issue but just ignore some other structural issue.

The whole MAX issue is a few bad assumptions and decisions, not some kind of corporate culture that a few crashes are ok because we can win a few more sales or make a little more profit.

I still hold my opinion that the failure that led to the ET crash should have been dealt with successfully by the crew. How any MAX crew wouldn't be able to recognize and correct an MCAS induced runaway stabilizer after the Lion Air crash and the EAD is beyond my comprehension. Either they weren't properly educated on the EAD or they couldn't react under pressure.

Everyone seems to have forgotten about the second software failure Boeing discovered

Wonder if that meant the pilots were facing even more problems to fix?

planecane wrote:

I still hold my opinion that the failure that led to the ET crash should have been dealt with successfully by the crew. How any MAX crew wouldn't be able to recognize and correct an MCAS induced runaway stabilizer after the Lion Air crash and the EAD is beyond my comprehension. Either they weren't properly educated on the EAD or they couldn't react under pressure.

That is pretty arrogant thing to say.

planecane wrote:

I still hold my opinion that the failure that led to the ET crash should have been dealt with successfully by the crew. How any MAX crew wouldn't be able to recognize and correct an MCAS induced runaway stabilizer after the Lion Air crash and the EAD is beyond my comprehension. Either they weren't properly educated on the EAD or they couldn't react under pressure.

It's very easy to say that from the safety of your keyboard weeks after the event. Meanwhile the ET crew were dealing with a bunch of other stuff at the same time. MCAS activation is not the same as a runaway stabiliser, even though the solution was the same.

scbriml wrote:

It's very easy to say that from the safety of your keyboard weeks after the event. Meanwhile the ET crew were dealing with a bunch of other stuff at the same time. MCAS activation is not the same as a runaway stabiliser, even though the solution was the same.

If we're going to hold Boeing to a high standard, how about we hold airlines/pilots to a high standard as well. With hindsight it's pretty easy to blame engineers for potentially not thinking through rare scenarios from the safety of a keyboard.

Advocating for one and not the other is a sign that it's not about industry safety. I want both mistakes fixed, don't you?

rcair1 wrote:

ArgentoSystems wrote:

planecane wrote:

If a house is burning down the firefighters put it out the same way. They don't need training based on if it started from an electrical overload or a candle falling over.

Not exactly correct. You use different types of fire-extinguishers for different fires. You don't put water on electrical fire, for example. Chemical fires is a different matter altogether. So yeah, they do need training to handle different type of fires.

Actually, in the context of a house fire ignited by electricity, you turn off the electricity and put water on it. Electricity doesn't burn, it heats stuff that burns.

In the case of burning liquids, you use a class B agent. The key is "class B", meaning that for a class of fire types, you use a class of agent, not a specific one. Oh sure, there are different brands/types that may be better/worse, but that is often marketing.

The analogy works. For runaway stab, you do runaway stab procedure.

The problem with mcas in the accident flights in my moderately informed opinion, was two fold. It was part of a cascading failure, which presented the pilots with multiple symptoms at relatively low altitude, confusing them, and it was too aggressive.

The first you address but increasing the robustness of the system that caused stab runnaway, the second you address but limiting system authority. The changes Boeing is making do both of those.

Now, should Boeing have done that initially? In a 20/20 hindsight world, that seems obvious. But, before the crashes, the argument that

"1) MCAS is not often used,
2) that if it fails, it is just a runaway stab trim which pilots already know how to deal with,

is not unreasonable.

Unfortunately, it seems no engineer had the imagination to ask,

"What if this thing fails during takeoff because of a left side aoa failure that causes a false high angle of attack and also causes concurrent stall warnings and stick shaker and unreliable airspeed, and it keeps trying to trim down hard, and confuses the crew, who may or may not be stellar pilots. Is that a problem?"

The answer to that question is, as we now know, yes it may be. (Not unqualified yes, because some crews managed it, but definitely a potential yes.). But it seems that the question was not asked, or if it was the answer was wrong.

And, no, I'm not being facetious here. The question to be asked is not simple. Also, as humans, we are subject to biases, probably confirmation bias played a role here.

What I don't believe is that Boeing engineers purposefully ignored and hid a fatal flaw. I'm less confident in management, but I've seen no evidence of malice at either Boeing of the faa. Errors, yes, malice no. If we do find malice, then we act. And perhaps we investigate.

But I believe this was an error, a serious one with deadly consequences, but an error. Not the first, in aviation, and unfortunately, not likely the last.

This, to me, is an excellent summary of the situation. I do not believe anybody at Boeing would ever deliberately compromise safety. They are all well aware that if the impression that they were cavalier about safety caught on that they would be finished; no airline would ever again buy their planes. They have fully embraced the idea that it is bad for business to kill your customers, or your customers’ customers.

But they are all human. One of the most difficult tasks in human activity is to put yourself in the place of someone with far less understanding of a situation than you have, and predict his/her response. I learned that myself the hard way teaching my daughter to drive. My signature illustrates it. As a pilot myself I find it incomprehensible that two pilots, who have been trained to deal with runaway trim, could experience uncommanded trim and not simply turn it off. And I find it even more incomprehensible that after one crash caused by that, and all the publicity surrounding it, AND Boeing sending out a bulletin to all pilots flying the plane outlining exactly what the problem is and what to do about it, that another crew does the same thing. But it happened.

There are a lot of posters saying that the 737 is inherently unsafe, that the MAX went too far, and a lot of stuff like that. Well, I do not agree. In an ideal world, when a new design for anything comes out everyone will scrap all the old ones and buy the new ones. In the real world this does not happen. And in the world of airliners, with the incredible amount of money involved, an old design gets replaced when its replacement makes more money or measurably improves safety. There are many ways to achieve the same goal, some more elegant than others The most elegant solution for the 737 is what Boeing wanted to do, which was replace it. But economic realities forced them to improve it yet again. It would have been nice had they been able to simply replace the entire control system with FBW, but again a number of real world realities precluded that. So did they stumble? Most definitely. But is it unrecoverable? I do not believe so. The fix as I have read about it should solve this problem once and for all. And in a couple of years it will be forgotten, and the MAX will continue on establishing the legacy of one of the most successful airliners of all time.

MSPNWA wrote:

scbriml wrote:

It's very easy to say that from the safety of your keyboard weeks after the event. Meanwhile the ET crew were dealing with a bunch of other stuff at the same time. MCAS activation is not the same as a runaway stabiliser, even though the solution was the same.

If we're going to hold Boeing to a high standard, how about we hold airlines/pilots to a high standard as well. With hindsight it's pretty easy to blame engineers for potentially not thinking through rare scenarios from the safety of a keyboard.

Advocating for one and not the other is a sign that it's not about industry safety. I want both mistakes fixed, don't you?

As long as pilots are human, groundcrew are human and air traffic controllers are human we are going to face human error on all aspects of plane safety

That's a given. It's not even up for debate.

It's acknowledged as by far the biggest contributor to plane crashes already. So the challenge for plane designers is to design planes that remove as much as possible the need for extra maintenance and pilot intervention

As such Max 737 has failed the industry. Simple as that.

SEPilot wrote:

rcair1 wrote:

ArgentoSystems wrote:

Not exactly correct. You use different types of fire-extinguishers for different fires. You don't put water on electrical fire, for example. Chemical fires is a different matter altogether. So yeah, they do need training to handle different type of fires.

Actually, in the context of a house fire ignited by electricity, you turn off the electricity and put water on it. Electricity doesn't burn, it heats stuff that burns.

In the case of burning liquids, you use a class B agent. The key is "class B", meaning that for a class of fire types, you use a class of agent, not a specific one. Oh sure, there are different brands/types that may be better/worse, but that is often marketing.

The analogy works. For runaway stab, you do runaway stab procedure.

The problem with mcas in the accident flights in my moderately informed opinion, was two fold. It was part of a cascading failure, which presented the pilots with multiple symptoms at relatively low altitude, confusing them, and it was too aggressive.

The first you address but increasing the robustness of the system that caused stab runnaway, the second you address but limiting system authority. The changes Boeing is making do both of those.

Now, should Boeing have done that initially? In a 20/20 hindsight world, that seems obvious. But, before the crashes, the argument that

"1) MCAS is not often used,
2) that if it fails, it is just a runaway stab trim which pilots already know how to deal with,

is not unreasonable.

Unfortunately, it seems no engineer had the imagination to ask,

"What if this thing fails during takeoff because of a left side aoa failure that causes a false high angle of attack and also causes concurrent stall warnings and stick shaker and unreliable airspeed, and it keeps trying to trim down hard, and confuses the crew, who may or may not be stellar pilots. Is that a problem?"

The answer to that question is, as we now know, yes it may be. (Not unqualified yes, because some crews managed it, but definitely a potential yes.). But it seems that the question was not asked, or if it was the answer was wrong.

And, no, I'm not being facetious here. The question to be asked is not simple. Also, as humans, we are subject to biases, probably confirmation bias played a role here.

What I don't believe is that Boeing engineers purposefully ignored and hid a fatal flaw. I'm less confident in management, but I've seen no evidence of malice at either Boeing of the faa. Errors, yes, malice no. If we do find malice, then we act. And perhaps we investigate.

But I believe this was an error, a serious one with deadly consequences, but an error. Not the first, in aviation, and unfortunately, not likely the last.

This, to me, is an excellent summary of the situation. I do not believe anybody at Boeing would ever deliberately compromise safety. They are all well aware that if the impression that they were cavalier about safety caught on that they would be finished; no airline would ever again buy their planes. They have fully embraced the idea that it is bad for business to kill your customers, or your customers’ customers.

But they are all human. One of the most difficult tasks in human activity is to put yourself in the place of someone with far less understanding of a situation than you have, and predict his/her response. I learned that myself the hard way teaching my daughter to drive. My signature illustrates it. As a pilot myself I find it incomprehensible that two pilots, who have been trained to deal with runaway trim, could experience uncommanded trim and not simply turn it off. And I find it even more incomprehensible that after one crash caused by that, and all the publicity surrounding it, AND Boeing sending out a bulletin to all pilots flying the plane outlining exactly what the problem is and what to do about it, that another crew does the same thing. But it happened.

There are a lot of posters saying that the 737 is inherently unsafe, that the MAX went too far, and a lot of stuff like that. Well, I do not agree. In an ideal world, when a new design for anything comes out everyone will scrap all the old ones and buy the new ones. In the real world this does not happen. And in the world of airliners, with the incredible amount of money involved, an old design gets replaced when its replacement makes more money or measurably improves safety. There are many ways to achieve the same goal, some more elegant than others The most elegant solution for the 737 is what Boeing wanted to do, which was replace it. But economic realities forced them to improve it yet again. It would have been nice had they been able to simply replace the entire control system with FBW, but again a number of real world realities precluded that. So did they stumble? Most definitely. But is it unrecoverable? I do not believe so. The fix as I have read about it should solve this problem once and for all. And in a couple of years it will be forgotten, and the MAX will continue on establishing the legacy of one of the most successful airliners of all time.

So you honestly believe Max 737 is a well designed plane?

It's badly designed hardware with software patches to try and make up for the bad design IMO

I believe I hold both pilots and engineers to the same high but realistic standard when I say that it is perfectly understandable that a couple of persons might not perform perfectly for some small amount of time on one day but it is not acceptable that a hundred persons get it wrong after thinking about something for months and having tens of meetings about the subject.

Interested wrote:

planecane wrote:

Interested wrote:

So you believe someone just imagined all of that?

And wrote a made up story that long? Why would they? What's the point?

The point? Some people like attention and get it by posting things like that.

The poster probably did briefly work for Boeing. I'm sure as in ALL corporate environments there were lazy engineers goofing off at work. There is probably a higher percentage at Boeing due to the engineers being unionized.

I'm sure there was some crusty old engineer always gossiping like he is the be all, end all expert on everything on the company. Every engineering department has someone like that.

So the guy takes some facts and embellishes to fit a narrative that people with your opinions eat up to get "likes" on a Reddit post and feel good about himself. He likely got fired or laid off and saw this post as a way to get some revenge on his former employer.

Like I said, there are things he states about the 787 that are not true. It makes absolutely no sense that Boeing would spend the time and money to fix the wing rib shear tie issue but just ignore some other structural issue.

The whole MAX issue is a few bad assumptions and decisions, not some kind of corporate culture that a few crashes are ok because we can win a few more sales or make a little more profit.

I still hold my opinion that the failure that led to the ET crash should have been dealt with successfully by the crew. How any MAX crew wouldn't be able to recognize and correct an MCAS induced runaway stabilizer after the Lion Air crash and the EAD is beyond my comprehension. Either they weren't properly educated on the EAD or they couldn't react under pressure.

Everyone seems to have forgotten about the second software failure Boeing discovered

Wonder if that meant the pilots were facing even more problems to fix?

Since that other fix related to control of flaps according to all reports and the flaps retracted fine per the FDR, there is nothing to say that had anything to do with this event. Also, nothing that wasn't related to the AoA sensor or MCAS/trim was mentioned in the preliminary report.

scbriml wrote:

planecane wrote:

I still hold my opinion that the failure that led to the ET crash should have been dealt with successfully by the crew. How any MAX crew wouldn't be able to recognize and correct an MCAS induced runaway stabilizer after the Lion Air crash and the EAD is beyond my comprehension. Either they weren't properly educated on the EAD or they couldn't react under pressure.

It's very easy to say that from the safety of your keyboard weeks after the event. Meanwhile the ET crew were dealing with a bunch of other stuff at the same time. MCAS activation is not the same as a runaway stabiliser, even though the solution was the same.

The EAD provided the detail that uncommanded nose down trim is possible on the 787MAX8 and 9 and if it was encountered the runaway stabilizer checklist should be performed. I agree with your opinion as it relates to the Lion Air crash because the MCAS issue presented itself slightly differently than what was trained as "runaway stabilizer." However, after that crash happened and the EAD was issued, there is no reason that a pilot flying the MAX should not have recognized the situation.

The "bunch of other stuff" they were dealing with were indications of runaway stabilizer right out of the EAD including the very first bullet item "continuous or intermittent stick shaker on the affected side only."

I'm sorry but the ET crew was either not properly trained as directed by the EAD or were not capable of properly executing the checklist under the stress of the situation.

Yes, it is easy for me to say from the safety of my keyboard but my expectation is that if somebody's job is a pilot that is responsible for over a hundred souls that they should be capable of responding properly to an emergency. I don't expect every pilot to be Sully or the crew of UAL 232 that were dealing with situations that nobody trained for or expected, I do expect every pilot to be able to handle an event that is an exact repeat of an event that happened four months earlier and had an EAD issued with information about the failure and recovery procedure.

planecane wrote:

The EAD provided the detail that uncommanded nose down trim is possible on the 787MAX8 and 9 and if it was encountered the runaway stabilizer checklist should be performed. I agree with your opinion as it relates to the Lion Air crash because the MCAS issue presented itself slightly differently than what was trained as "runaway stabilizer." However, after that crash happened and the EAD was issued, there is no reason that a pilot flying the MAX should not have recognized the situation.

The "bunch of other stuff" they were dealing with were indications of runaway stabilizer right out of the EAD including the very first bullet item "continuous or intermittent stick shaker on the affected side only."

I'm sorry but the ET crew was either not properly trained as directed by the EAD or were not capable of properly executing the checklist under the stress of the situation.

Yes, it is easy for me to say from the safety of my keyboard but my expectation is that if somebody's job is a pilot that is responsible for over a hundred souls that they should be capable of responding properly to an emergency. I don't expect every pilot to be Sully or the crew of UAL 232 that were dealing with situations that nobody trained for or expected, I do expect every pilot to be able to handle an event that is an exact repeat of an event that happened four months earlier and had an EAD issued with information about the failure and recovery procedure.

What you write seems pretty accurate. However it totally ignores any of the multitude of sins committed by Boeing, so it comes across rather unbalanced. The ET crew might well have handled the situation less than perfectly (I still don't think we're in a position to blame them) yet they should never have been put in that position by the manufacturer.

planecane wrote:

scbriml wrote:

planecane wrote:

I still hold my opinion that the failure that led to the ET crash should have been dealt with successfully by the crew. How any MAX crew wouldn't be able to recognize and correct an MCAS induced runaway stabilizer after the Lion Air crash and the EAD is beyond my comprehension. Either they weren't properly educated on the EAD or they couldn't react under pressure.

It's very easy to say that from the safety of your keyboard weeks after the event. Meanwhile the ET crew were dealing with a bunch of other stuff at the same time. MCAS activation is not the same as a runaway stabiliser, even though the solution was the same.

The EAD provided the detail that uncommanded nose down trim is possible on the 787MAX8 and 9 and if it was encountered the runaway stabilizer checklist should be performed. I agree with your opinion as it relates to the Lion Air crash because the MCAS issue presented itself slightly differently than what was trained as "runaway stabilizer." However, after that crash happened and the EAD was issued, there is no reason that a pilot flying the MAX should not have recognized the situation.

The "bunch of other stuff" they were dealing with were indications of runaway stabilizer right out of the EAD including the very first bullet item "continuous or intermittent stick shaker on the affected side only."

I'm sorry but the ET crew was either not properly trained as directed by the EAD or were not capable of properly executing the checklist under the stress of the situation.

Yes, it is easy for me to say from the safety of my keyboard but my expectation is that if somebody's job is a pilot that is responsible for over a hundred souls that they should be capable of responding properly to an emergency. I don't expect every pilot to be Sully or the crew of UAL 232 that were dealing with situations that nobody trained for or expected, I do expect every pilot to be able to handle an event that is an exact repeat of an event that happened four months earlier and had an EAD issued with information about the failure and recovery procedure.

Oh stop it. Somebody will have to come back with mentourpilot video showing manual trim didnt work again, and electric did not have enough authority etc again, then you will have to say they should have applied unreliable airspeed NNC and pulled thrust back anyway again , then someone will say they started checklists again and you will say its not the report again and someone will say the report is not a transcript again etc. etc. etc. again ad infinitum.
Just not worth it, and its getting boring.

Ray

The focus right now is very much on figuring out whether this plane should have ever been certified to fly and figuring out when and if it will be certified to fly again in the future

The wider aviation world (at least) accepts this is a disaster caused by a plane design etc rather than pilot error

Virtual737 wrote:

planecane wrote:

The EAD provided the detail that uncommanded nose down trim is possible on the 787MAX8 and 9 and if it was encountered the runaway stabilizer checklist should be performed. I agree with your opinion as it relates to the Lion Air crash because the MCAS issue presented itself slightly differently than what was trained as "runaway stabilizer." However, after that crash happened and the EAD was issued, there is no reason that a pilot flying the MAX should not have recognized the situation.

The "bunch of other stuff" they were dealing with were indications of runaway stabilizer right out of the EAD including the very first bullet item "continuous or intermittent stick shaker on the affected side only."

I'm sorry but the ET crew was either not properly trained as directed by the EAD or were not capable of properly executing the checklist under the stress of the situation.

Yes, it is easy for me to say from the safety of my keyboard but my expectation is that if somebody's job is a pilot that is responsible for over a hundred souls that they should be capable of responding properly to an emergency. I don't expect every pilot to be Sully or the crew of UAL 232 that were dealing with situations that nobody trained for or expected, I do expect every pilot to be able to handle an event that is an exact repeat of an event that happened four months earlier and had an EAD issued with information about the failure and recovery procedure.

What you write seems pretty accurate. However it totally ignores any of the multitude of sins committed by Boeing, so it comes across rather unbalanced. The ET crew might well have handled the situation less than perfectly (I still don't think we're in a position to blame them) yet they should never have been put in that position by the manufacturer.

Boeing is 100% to blame for the Lion Air crash. Are there pilots that would have saved that plane? Absolutely, including the crew on the prior flight of the aircraft. However, I put all the blame on Boeing for the way they designed MCAS and that they did not add the slightly different failure mode to the FCOM. With respect to ET, Boeing's original sins put the plane in the situation but the corrective action described in the EAD put the onus on the crew to be able to recover.

Interested wrote:

The focus right now is very much on figuring out whether this plane should have ever been certified to fly and figuring out when and if it will be certified to fly again in the future

The wider aviation world (at least) accepts this is a disaster caused by a plane design etc rather than pilot error

It is definitely a when not if as far as being certified to fly again. Otherwise, EVERY aircraft, Boeing, Airbus, Embraer, Bombardier, etc. certified with the same processes must be recertified. Just because another model hasn't had a problem doesn't mean something wasn't missed.

Lion Air was caused by a combination of bad design and bad documentation/training. ET was caused by a combination of bad design and pilot error. Neither would have happened if the software fix was the original software.

planecane wrote:

Boeing's original sins put the plane in the situation but the corrective action described in the EAD put the onus on the crew to be able to recover.

That the thing. I'm still not convinced that we can say for sure that following the EAD to the letter would definitely have saved the day. I think I'm right in saying that Boeing, since the ET incident, have not flown a MAX in exactly the same circumstance as the ET crew (hot & high, low altitude above terrain etc etc) and replicated the trim movement. Of course you can't fully replicate the fact that the ET crew would not have known it was about to happen, but I'd take my hat off to any Boeing pilots that copied the ET flight parameters in a REAL MAX, without the MCAS changes and let them tell me that all you have to do is follow the EAD after they successfully landed.

We still don't know for sure that the trim could be moved manually fast enough to recover, or even moved at all. According to the CVR from the ET incident, they couldn't move it. Admittedly this might have a lot to do with the kinetic energy they had due to the continually high throttle.

Do the few Max sims currently available have fully operational MCAS?

Virtual737 wrote:

planecane wrote:

Boeing's original sins put the plane in the situation but the corrective action described in the EAD put the onus on the crew to be able to recover.

That the thing. I'm still not convinced that we can say for sure that following the EAD to the letter would definitely have saved the day. I think I'm right in saying that Boeing, since the ET incident, have not flown a MAX in exactly the same circumstance as the ET crew (hot & high, low altitude above terrain etc etc) and replicated the trim movement. Of course you can't fully replicate the fact that the ET crew would not have known it was about to happen, but I'd take my hat off to any Boeing pilots that copied the ET flight parameters in a REAL MAX, without the MCAS changes and let them tell me that all you have to do is follow the EAD after they successfully landed.

We still don't know for sure that the trim could be moved manually fast enough to recover, or even moved at all. According to the CVR from the ET incident, they couldn't move it. Admittedly this might have a lot to do with the kinetic energy they had due to the continually high throttle.

I agree that no Boeing test pilot is going to attempt that so close to the ground in a real aircraft. I'm sure they have done it in a simulator.

What we do know for sure from the FDR traces and partial CVR transcript is that they were retrimming after the second MCAS commanded nose down trim event AND the stabilizer was moving. The procedure said to use manual electric trim to balance control column forces and then move the switches to cutout. They moved the switches to cutout while they were trimming ANU and the stabilizer moved until the moment they moved the switches.

Revelation wrote:

Seems an discussion of anything that doesn't fall in to the "compliance with all applicable regulations" is off the table, like shouldn't the regulations be different, or shouldn't we look at how MCAS happened in the first place...

Perhaps the focus of another group meeting at the CAA's offices in London?

Revelation wrote:

The risk is that after the 90 days various regulators, perhaps some meeting at the CAA's offices in London, tell them that the fix is fine but how did this mistake happen, and now we begin another 90 day or more process that they could have started much earlier.

I think this scenario is more than likely. The fix is straightforward, but how did you manage to make this stupidest mistake? I think it warrants reviewing every line of s/w on that plane.

Revelation wrote:

ArgentoSystems wrote:

planecane wrote:

I still hold my opinion that the failure that led to the ET crash should have been dealt with successfully by the crew. How any MAX crew wouldn't be able to recognize and correct an MCAS induced runaway stabilizer after the Lion Air crash and the EAD is beyond my comprehension. Either they weren't properly educated on the EAD or they couldn't react under pressure.

That is pretty arrogant thing to say.

Why is it arrogant?

That implies the crew did something wrong. ("Because the other crew managed to save plane in the same situation").

ArgentoSystems wrote:

Revelation wrote:

ArgentoSystems wrote:

That is pretty arrogant thing to say.

Why is it arrogant?

That implies the crew did something wrong. ("Because the other crew managed to save plane in the same situation").

Not arrogant, factual. The ET crew did do something wrong. They did not follow the procedure outlined in the EAD. They moved the trim switches to cutout before they balanced the control forces.

It is very sad. The crew didn't put the aircraft in that position but they should have recovered. They were acting correctly and then rushed to hit the cutout switches before they reached that step in the procedure. 10 more seconds and the plane would have been back in trim.

Interested wrote:

SEPilot wrote:

rcair1 wrote:

Actually, in the context of a house fire ignited by electricity, you turn off the electricity and put water on it. Electricity doesn't burn, it heats stuff that burns.

In the case of burning liquids, you use a class B agent. The key is "class B", meaning that for a class of fire types, you use a class of agent, not a specific one. Oh sure, there are different brands/types that may be better/worse, but that is often marketing.

The analogy works. For runaway stab, you do runaway stab procedure.

The problem with mcas in the accident flights in my moderately informed opinion, was two fold. It was part of a cascading failure, which presented the pilots with multiple symptoms at relatively low altitude, confusing them, and it was too aggressive.

The first you address but increasing the robustness of the system that caused stab runnaway, the second you address but limiting system authority. The changes Boeing is making do both of those.

Now, should Boeing have done that initially? In a 20/20 hindsight world, that seems obvious. But, before the crashes, the argument that

"1) MCAS is not often used,
2) that if it fails, it is just a runaway stab trim which pilots already know how to deal with,

is not unreasonable.

Unfortunately, it seems no engineer had the imagination to ask,

"What if this thing fails during takeoff because of a left side aoa failure that causes a false high angle of attack and also causes concurrent stall warnings and stick shaker and unreliable airspeed, and it keeps trying to trim down hard, and confuses the crew, who may or may not be stellar pilots. Is that a problem?"

The answer to that question is, as we now know, yes it may be. (Not unqualified yes, because some crews managed it, but definitely a potential yes.). But it seems that the question was not asked, or if it was the answer was wrong.

And, no, I'm not being facetious here. The question to be asked is not simple. Also, as humans, we are subject to biases, probably confirmation bias played a role here.

What I don't believe is that Boeing engineers purposefully ignored and hid a fatal flaw. I'm less confident in management, but I've seen no evidence of malice at either Boeing of the faa. Errors, yes, malice no. If we do find malice, then we act. And perhaps we investigate.

But I believe this was an error, a serious one with deadly consequences, but an error. Not the first, in aviation, and unfortunately, not likely the last.

This, to me, is an excellent summary of the situation. I do not believe anybody at Boeing would ever deliberately compromise safety. They are all well aware that if the impression that they were cavalier about safety caught on that they would be finished; no airline would ever again buy their planes. They have fully embraced the idea that it is bad for business to kill your customers, or your customers’ customers.

But they are all human. One of the most difficult tasks in human activity is to put yourself in the place of someone with far less understanding of a situation than you have, and predict his/her response. I learned that myself the hard way teaching my daughter to drive. My signature illustrates it. As a pilot myself I find it incomprehensible that two pilots, who have been trained to deal with runaway trim, could experience uncommanded trim and not simply turn it off. And I find it even more incomprehensible that after one crash caused by that, and all the publicity surrounding it, AND Boeing sending out a bulletin to all pilots flying the plane outlining exactly what the problem is and what to do about it, that another crew does the same thing. But it happened.

There are a lot of posters saying that the 737 is inherently unsafe, that the MAX went too far, and a lot of stuff like that. Well, I do not agree. In an ideal world, when a new design for anything comes out everyone will scrap all the old ones and buy the new ones. In the real world this does not happen. And in the world of airliners, with the incredible amount of money involved, an old design gets replaced when its replacement makes more money or measurably improves safety. There are many ways to achieve the same goal, some more elegant than others The most elegant solution for the 737 is what Boeing wanted to do, which was replace it. But economic realities forced them to improve it yet again. It would have been nice had they been able to simply replace the entire control system with FBW, but again a number of real world realities precluded that. So did they stumble? Most definitely. But is it unrecoverable? I do not believe so. The fix as I have read about it should solve this problem once and for all. And in a couple of years it will be forgotten, and the MAX will continue on establishing the legacy of one of the most successful airliners of all time.

So you honestly believe Max 737 is a well designed plane?

It's badly designed hardware with software patches to try and make up for the bad design IMO

Actually, it is an extremely well designed plane. It has competed on even terms with a design that is twenty years newer. That is no easy feat. It is much, much easier to start with blank paper than to update an old design in order to compete with a new one. The fact that Boeing has been able to do so is an incredible feat of engineering.

planecane wrote:

Interested wrote:

The focus right now is very much on figuring out whether this plane should have ever been certified to fly and figuring out when and if it will be certified to fly again in the future

The wider aviation world (at least) accepts this is a disaster caused by a plane design etc rather than pilot error

It is definitely a when not if as far as being certified to fly again. Otherwise, EVERY aircraft, Boeing, Airbus, Embraer, Bombardier, etc. certified with the same processes must be recertified. Just because another model hasn't had a problem doesn't mean something wasn't missed.

Lion Air was caused by a combination of bad design and bad documentation/training. ET was caused by a combination of bad design and pilot error. Neither would have happened if the software fix was the original software.

I'm talking about whether you can actually count 737 Max as a grandfathered plane and following the move of engines and lack of stability etc whether it's safe to be certified

I'm not talking about the process I'm talking about what we know about the plane now

SEPilot wrote:

Interested wrote:

SEPilot wrote:

This, to me, is an excellent summary of the situation. I do not believe anybody at Boeing would ever deliberately compromise safety. They are all well aware that if the impression that they were cavalier about safety caught on that they would be finished; no airline would ever again buy their planes. They have fully embraced the idea that it is bad for business to kill your customers, or your customers’ customers.

But they are all human. One of the most difficult tasks in human activity is to put yourself in the place of someone with far less understanding of a situation than you have, and predict his/her response. I learned that myself the hard way teaching my daughter to drive. My signature illustrates it. As a pilot myself I find it incomprehensible that two pilots, who have been trained to deal with runaway trim, could experience uncommanded trim and not simply turn it off. And I find it even more incomprehensible that after one crash caused by that, and all the publicity surrounding it, AND Boeing sending out a bulletin to all pilots flying the plane outlining exactly what the problem is and what to do about it, that another crew does the same thing. But it happened.

There are a lot of posters saying that the 737 is inherently unsafe, that the MAX went too far, and a lot of stuff like that. Well, I do not agree. In an ideal world, when a new design for anything comes out everyone will scrap all the old ones and buy the new ones. In the real world this does not happen. And in the world of airliners, with the incredible amount of money involved, an old design gets replaced when its replacement makes more money or measurably improves safety. There are many ways to achieve the same goal, some more elegant than others The most elegant solution for the 737 is what Boeing wanted to do, which was replace it. But economic realities forced them to improve it yet again. It would have been nice had they been able to simply replace the entire control system with FBW, but again a number of real world realities precluded that. So did they stumble? Most definitely. But is it unrecoverable? I do not believe so. The fix as I have read about it should solve this problem once and for all. And in a couple of years it will be forgotten, and the MAX will continue on establishing the legacy of one of the most successful airliners of all time.

So you honestly believe Max 737 is a well designed plane?

It's badly designed hardware with software patches to try and make up for the bad design IMO

Actually, it is an extremely well designed plane. It has competed on even terms with a design that is twenty years newer. That is no easy feat. It is much, much easier to start with blank paper than to update an old design in order to compete with a new one. The fact that Boeing has been able to do so is an incredible feat of engineering.

Extremely well designed providing safety isn't a target

Does no one else think it's a serious problem that manual trim didn't work/is so difficult to move? This requires some design change, too, imho.
The manual trim should not take excessive force to move up to and including Vmo.
What a lousy design!

planecane wrote:

Not arrogant, factual. The ET crew did do something wrong. They did not follow the procedure outlined in the EAD. They moved the trim switches to cutout before they balanced the control forces.

The Emergency Airworthiness Directive did not explicitly say that the column control forces needed to be balanced before moving Stab Trim switches to Cutout.

Runaway Stabilizer

Disengage autopilot and control airplane pitch attitude with control column and main electric trim as required. If relaxing the column causes the trim to move, set stabilizer trim switches to CUTOUT. If runaway continues, hold the stabilizer trim wheel against rotation and trim the airplane manually.

In the event an uncommanded nose down stabilizer trim is experienced on the 737-8/-9, in conjunction with one or more of the indications or effects listed below, do the existing AFM Runaway Stabilizer procedure above, ensuring that the STAB TRIM CUTOUT switches are set to CUTOUT...

Electric stabilizer trim can be used to neutralize control column pitch forces before moving the STAB TRIM CUTOUT switches to CUTOUT. Manual stabilizer trim can be used before and after the STAB TRIM CUTOUT switches are moved to CUTOUT.

If the EAD actually meant what you said, it would have read, "...do the existing AFM Runaway Stabilizer procedure above, ensuring to use Electric Trim to balance the control column forces before moving the STAB TRIM CUTOUT switches to CUTOUT." And it would not have stated that "Manual stabilizer trim can be used before and after the STAB TRIM CUTOUT switches are moved to CUTOUT."

namezero111111 wrote:

Does no one else think it's a serious problem that manual trim didn't work/is so difficult to move? This requires some design change, too, imho.
The manual trim should not take excessive force to move up to and including Vmo.
What a lousy design!

I'm assuming it's not really being needed much in recent years. And when it has its not been anywhere near as severe a problem to deal with.

Otherwise something better would be getting used already surely?

planecane wrote:

Interested wrote:

The focus right now is very much on figuring out whether this plane should have ever been certified to fly and figuring out when and if it will be certified to fly again in the future

The wider aviation world (at least) accepts this is a disaster caused by a plane design etc rather than pilot error

It is definitely a when not if as far as being certified to fly again. Otherwise, EVERY aircraft, Boeing, Airbus, Embraer, Bombardier, etc. certified with the same processes must be recertified. Just because another model hasn't had a problem doesn't mean something wasn't missed.

Lion Air was caused by a combination of bad design and bad documentation/training. ET was caused by a combination of bad design and pilot error. Neither would have happened if the software fix was the original software.

Lion Air dispatched the plane with a faulty sensor.

https://www.latimes.com/business/la-fi- ... story.html

planecane wrote:

ArgentoSystems wrote:

Revelation wrote:

Why is it arrogant?

That implies the crew did something wrong. ("Because the other crew managed to save plane in the same situation").

Not arrogant, factual. The ET crew did do something wrong. They did not follow the procedure outlined in the EAD. They moved the trim switches to cutout before they balanced the control forces.

It is very sad. The crew didn't put the aircraft in that position but they should have recovered. They were acting correctly and then rushed to hit the cutout switches before they reached that step in the procedure. 10 more seconds and the plane would have been back in trim.

Except the advice to use electric trim to neutralize stabilizer before hitting cutoff switches is the very LAST item on Boeing’s badly written checklist.

If you go by item 1, 2, 3 etc you will reach the section that advices you to use cutoff of electrical trim early on, and the warning not to do it until stabilizer “neutral” at the very end.

So first, Boeing royally screws up MCAS v1 implementation, then second screws up the emergency bulletin set to prevent another MCAS-related accident from happening again...

Boof02671 wrote:

Lion Air dispatched the plane with a faulty sensor.

https://www.latimes.com/business/la-fi- ... story.html

That has not actually been established. I am told the FDR does not actually get a direct AOA analogue reading from the sensor, it records a digital value.

I haven’t yet been able to find out where it comes from, it might be the FCC or ADIRU.

hilram wrote:

planecane wrote:

ArgentoSystems wrote:

That implies the crew did something wrong. ("Because the other crew managed to save plane in the same situation").

Not arrogant, factual. The ET crew did do something wrong. They did not follow the procedure outlined in the EAD. They moved the trim switches to cutout before they balanced the control forces.

It is very sad. The crew didn't put the aircraft in that position but they should have recovered. They were acting correctly and then rushed to hit the cutout switches before they reached that step in the procedure. 10 more seconds and the plane would have been back in trim.

Except the advice to use electric trim to neutralize stabilizer before hitting cutoff switches is the very LAST item on Boeing’s badly written checklist.

If you go by item 1, 2, 3 etc you will reach the section that advices you to use cutoff of electrical trim early on, and the warning not to do it until stabilizer “neutral” at the very end.

So first, Boeing royally screws up MCAS v1 implementation, then second screws up the emergency bulletin set to prevent another MCAS-related accident from happening again...

The VERY first sentence in the procedure is:

"Disengage autopilot and control airplane pitch attitude with control column and main electric trim as required"

I don't understand how this is in any way, shape, or form unclear.

The note at the bottom isn't advising the use of electric trim, it is describing what methods of trim will work depending on the position of the cutout switches. The procedure specifically says to use "main electric trim as required" as the second item after disengaging autopilot.

The other note specific to the max is instructing that the cutout switches not be returned to normal position.

Boeing didn't screw up the emergency bulletin. If you do what the words in the EAD instruct, the MCAS induced runaway stabilizer is fixed. The FAA is the one that issued the bulletin, not Boeing. Even if Boeing submitted the text, the FAA reviewed it and approved it so they bear final responsibility for the wording.

Interested wrote:

I'm assuming it's not really being needed much in recent years. And when it has its not been anywhere near as severe a problem to deal with.

Otherwise something better would be getting used already surely?

Even if with the hours clocked on NG and MAX together no one noticed (or Boeing knew and ignored) the trim difficulties it should undergo revision now that it is known.

It is there for a reason, and I would certainly expect it to work properly over the entire flight envelope, and that includes both airspeed and out-of-trim condition.

namezero111111 wrote:

Interested wrote:

I'm assuming it's not really being needed much in recent years. And when it has its not been anywhere near as severe a problem to deal with.

Otherwise something better would be getting used already surely?

Even if with the hours clocked on NG and MAX together no one noticed (or Boeing knew and ignored) the trim difficulties it should undergo revision now that it is known.

It is there for a reason, and I would certainly expect it to work properly over the entire flight envelope, and that includes both airspeed and out-of-trim condition.

The difficulties of using the manual trim wheel seem to have existed since the 737-100. The "roller coaster" procedure was in the 737-200 FCOM.

The manual trim wheel is there if the electric trim stops functioning or is cut off. It is meant as a backup for the electric trim, not for recovery of severe out of trim situations. For the aircraft to get to the severe out of trim, the elecric motor is functioning and therefore can be assumed to be available to get it back into trim.

planecane wrote:

namezero111111 wrote:

Interested wrote:

I'm assuming it's not really being needed much in recent years. And when it has its not been anywhere near as severe a problem to deal with.

Otherwise something better would be getting used already surely?

Even if with the hours clocked on NG and MAX together no one noticed (or Boeing knew and ignored) the trim difficulties it should undergo revision now that it is known.

It is there for a reason, and I would certainly expect it to work properly over the entire flight envelope, and that includes both airspeed and out-of-trim condition.

The difficulties of using the manual trim wheel seem to have existed since the 737-100. The "roller coaster" procedure was in the 737-200 FCOM.

The manual trim wheel is there if the electric trim stops functioning or is cut off. It is meant as a backup for the electric trim, not for recovery of severe out of trim situations. For the aircraft to get to the severe out of trim, the elecric motor is functioning and therefore can be assumed to be available to get it back into trim.

Not for 'real' stab trim runaway recovery then?

Ray