Boeing Systemic Problems Continue

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yycflyguy
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Re: Boeing Systemic Problems Continue

Post by yycflyguy »

2R wrote:
Tue Dec 24, 2019 7:57 am
Some may have thought Mcdonnel Douglas too big to fail . Never underestimate the Power of the dark side :)
Did McDonnell Douglas have billions of dollars in military contracts?
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2R
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Re: Boeing Systemic Problems Continue

Post by 2R »

They built many successful fighter aircraft. Their designers built the F 4 , F 18 ,CF 18 . Missile and many secret projects that are still hush hush .
They did not build post office vans or canoes like Gruman to keep production lines working between big contracts.
The production line of the DC 10 was impressive .Like a cross between huge industrial ballet and Dantes inferno .
They had many successful space launches and involvement in space programs , designing and fabrication of things that did not exist until they made them.

Amazing what some people achieved with slide rules and log tables :)
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Raymond Hall
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Re: Boeing Systemic Problems Continue

Post by Raymond Hall »

So now the challenge is restoring public confidence...from this evening's New York Times:

Boeing Can’t Fly Its 737 Max, but It’s Ready to Sell Its Safety

The company knows travelers are wary of its plane, so it has prepared presentations with strategies for airlines to help win back the public’s trust.

Since Boeing’s 737 Max jet was grounded in March, after two crashes killed 346 people, a question has loomed for the company: Would passengers be too scared to fly on the plane once it returned to the air?

It turns out that even as Boeing continues to work on technical fixes to the plane that are needed for regulatory approval, it has repeatedly surveyed thousands of passengers around the world to try to find out the answer. The latest results, from this month, found that 40 percent of regular fliers said they would be unwilling to fly on the Max.

So, in a series of conference calls with airlines and in 40 pages of accompanying presentation materials that were reviewed by The New York Times, Boeing laid out strategies for airlines to help win back the public’s trust and convince travelers that the company’s most popular plane is safe.

https://www.nytimes.com/2019/12/24/busi ... e=Homepage
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2R
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Re: Boeing Systemic Problems Continue

Post by 2R »

How many of the engineers who signed off the aircraft wore the steel pinky ring ?
Did they forget the Kipling ceremony ?

The ATPL issued by the FAA requires that the person holding the certificate be of good moral character.
I wonder how many ATPL certificates will be revoked .
Or will they be Jedi mind tricked into believing "
That these are not the certificates/ Licences ,you are looking for "

I would not be shocked if the chief test pilot gets promoted and not sent to fly rubber dog shite out of Hong Kong
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Last edited by 2R on Sun Dec 29, 2019 4:50 pm, edited 1 time in total.

L39Guy
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Re: Boeing Systemic Problems Continue

Post by L39Guy »

2R wrote:
Sun Dec 29, 2019 1:50 pm
How many of the engineers who signed off the aircraft were the steel pinky ring ?
Did they forget the Kipling ceremony ?

The ATPL issued by the FAA requires that the person holding the certificate be of good moral character.
I wonder how many ATPL certificates will be revoked .
Or will they be Jedi mind tricked into believing "
That these are not the certificates/ Licences ,you are looking for "

I would not be shocked if the chief test pilot gets promoted and not sent to fly rubber dog shite out of Hong Kong
First of all, the pinky iron ring and the Kipling oath are a Canadian tradition not American and it is likely these were US engineers signing off on this.

Secondly, all engineering involves risk management and compromise. If you want an absolutely fool proof aircraft, you can have one but it will either never get off the ground as it will be too heavy with redundancies or too expensive.

If you read the Indonesian report (all 380 pages of it) you will see that Boeing used sound reasoning and judgement with the MCAS. They assumed that professional pilots trained and type-rated to fly the B737 could do an unreliable airspeed (UAS) drill (which would have controlled the airspeed so they could manually trim the aircraft) and perform a stab trim runaway drill. These are all reasonable assumptions.

If you read the report you will learn that in the Lion Air accident, the captain called for the drill but the FO did not know it and the CVR records him flipping through pages of the QRH looking for it. Finally, the captains says "10.2", meaning page 10.2 of the QRH. Nevertheless, why the captain could not set 80% power and a 10 degree pitch attitude all by himself escapes me.

With respect to the stab trim, 26 (twenty-six) times the MCAS kicked in and he trimmed the aircraft back to neutral using the trim switches by his left thumb. How many times does the trim have to runaway (uncommanded for whatever the reason) before it sinks in to shut off the trim (stab trim runaway drill, another memory item).

The reasoning of the engineers and others that an MCAS failure like this was manageable was proven the day before when that same Lion Air aircraft had the MCAS event, the pilots did the unreliable airspeed drill, then the stab trim runaway drill then flew the aircraft for an hour and a half to its intended destination. Obviously, the MAX is a flyable aircraft with this MCAS failure in the hands of trained line pilots.

If engineers and others can no longer assume that type rated pilots can do a simple drill such as UAS (and in all three events they had two minutes to do it prior to Flaps Zero and MCAS kicking in), then the assumption that pilots can manage something more complex such as an engine failure on the runway, at V1 or in the air is no longer valid either. And if that is the case, then no multi-engine aircraft capable of asymmetric thrust should be flying either.
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2R
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Re: Boeing Systemic Problems Continue

Post by 2R »

If it just requires pilot training ,and pilots to do their jobs.

Why is it still grounded ?

Surely they could have retrained them all by now ?

Or is it the reasoning . It is taking so long to find a solution is because there is no real problem ?
Aviation has never been safer .

That first crash may have been avoided if the aircraft had been grounded as the previous crew had control issues , but for some reason the crew did not communicate the issues in a manner that would have mitigated the risk to the next flight. Getting a control issue Dvfr is easier to handle than a control issue while IMC .

The Kipling ceremony is all about trust.

The issues raised by the Boeing test pilot were not communicated in a way that resulted in mitigation of those issues . But were communicated in a manner to obfuscate the issues using " Jedi mind tricks"
Others regulators may not be as generous and demand to witness test flights through video links.

Trust is like Virginity , you only need to get fooked once to lose it :)
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L39Guy
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Re: Boeing Systemic Problems Continue

Post by L39Guy »

The MAX is still grounded because this is no longer a technical or certification issue - the MCAS was fixed a long time ago. This is a political issue and when politics and politicians get involved it get really stupid, really fast. You can train the pilots all you want but until the aircraft has a valid C of A, what is the point?

I don't recall what the weather was for the Lion Air crash but the Ethiopean one as clear and million VFR and after the AD about the MCAS had been issued that reminded crews of the UAS and stab trim runaway drills as well as providing the symptoms of a MCAS failure. How do you explain that crash when the captain did not do the UAS drill, let alone the runaway trim drill with full knowledge of MCAS?

Professional pilots are paid to know their stuff, particularly recall drills. I don't think that's too much to ask. Do you?
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2R
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Re: Boeing Systemic Problems Continue

Post by 2R »

You seem convinced that these accidents are the pilots fault ?
And yet the aircraft are still grounded and may not fly revenue flights until March. Which march is anyone's guess.

I am trying to keep an open mind .

Learn from the mistakes of others, you will not live long enough to make them all yourself.

https://www.airliners.net/forum/viewtop ... start=5550
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L39Guy
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Re: Boeing Systemic Problems Continue

Post by L39Guy »

Have you read the accident report or are you relying on such knowledgeable Aviation publication like the G and Mail, New York Times, Washington Post, etc.?

If you read the Indonesian report, which I think is very well done, there is plenty of blame allotted but the failure of the crew to do what they (should) have been trained to do is blindingly obvious.

Read the report, cover to cover, then we can chat again.
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corethatthermal
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Re: Boeing Systemic Problems Continue

Post by corethatthermal »

you will see that Boeing used sound reasoning and judgement with the MCAS.
Thats BULLSHIT ! A system with only 1 driving sensor ( instead of what should have been 3 ) A system that went 3+ times quicker than any previous system ( and FAA was not informed ) and a system that would drive trim down then stop for 5 seconds then start again,,,,all this stuff was not known to pilots flying the A/C ! And all the bells and whistles AND the stick shaker And where is the MCAS switch WHY combine it with the yoke trim system. All it should have taken was 1 person at Boeing to do a simulated sensor failure in the sim to find out the repercussions !
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2R
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Re: Boeing Systemic Problems Continue

Post by 2R »

I stayed in a holiday inn last week and I am an avid reader of the back of toilet doors at airports and flying clubs . Although I must say the quality of art and Intel gleaned from the rambling scribes of the outhouse has gone down since the internet .

The Seattle Times has some great insight into the issue , but they have not assigned blame yet , and are still digging through the facts . They are a bit biased as Seattle does have a lot of great Boeing employees who have contributed to make aviation as safe as it is today .

There are few media outlets that are considered papers of record . That is a byproduct of the internet .

The record is still open and the investigations are still ongoing . Hence the Aircraft are still grounded .
QED
https://www.seattletimes.com/business/boeing-aerospace/
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L39Guy
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Re: Boeing Systemic Problems Continue

Post by L39Guy »

corethatthermal wrote:
Sun Dec 29, 2019 8:14 pm
you will see that Boeing used sound reasoning and judgement with the MCAS.
Thats BULLSHIT ! A system with only 1 driving sensor ( instead of what should have been 3 ) A system that went 3+ times quicker than any previous system ( and FAA was not informed ) and a system that would drive trim down then stop for 5 seconds then start again,,,,all this stuff was not known to pilots flying the A/C ! And all the bells and whistles AND the stick shaker And where is the MCAS switch WHY combine it with the yoke trim system. All it should have taken was 1 person at Boeing to do a simulated sensor failure in the sim to find out the repercussions !
Easy on the language, cowboy.

I agree that MCAS needs to be redesigned to be dual sensor, less aggressive and limited to a smaller, maximum angle.

But a single point of failure is nothing new to aircraft. Engine failures and a window blowing out are also single point of failures. That's why there are emergency procedures including those that must be memorized.

The Ethiopian pilots knew about MCAS - explain to me why they didn't do the UAS drill which would have at least allowed them control the aircraft even with MCAS. And how about the stab trim runaway drill for what was by all appearance to be a stab trim runaway.

Pilots are the last line of defense. This event was perfectly manageable just like an engine failure, which is also a single point of failure. But the pilots have to be competent - the Lion Air pilots the day before were, the ones the next day were not. please read the report.
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Duke Point
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Re: Boeing Systemic Problems Continue

Post by Duke Point »

I gotta agree with L39Guy.

We live in a blameless society when it comes to people. NEVER blame the individual. Look elsewhere.

Memory drills were forgotten, ignored, or done incorrectly. Yes MCAS V.1 was poorly designed, but the 737's in question were NEVER uncontrollable.

Memory drills are memory drills for a reason, and these crashes --would not have occurred--- if the proper memory drills had been followed. Unfortunately this valuable lesson will likely be lost in the media firestorm, and sloppy pilots will continue to make fundamental errors.

DP.
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TFTMB heavy
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Re: Boeing Systemic Problems Continue

Post by TFTMB heavy »

L39Guy wrote:
Sun Dec 29, 2019 8:44 pm
corethatthermal wrote:
Sun Dec 29, 2019 8:14 pm
you will see that Boeing used sound reasoning and judgement with the MCAS.
Thats BULLSHIT ! A system with only 1 driving sensor ( instead of what should have been 3 ) A system that went 3+ times quicker than any previous system ( and FAA was not informed ) and a system that would drive trim down then stop for 5 seconds then start again,,,,all this stuff was not known to pilots flying the A/C ! And all the bells and whistles AND the stick shaker And where is the MCAS switch WHY combine it with the yoke trim system. All it should have taken was 1 person at Boeing to do a simulated sensor failure in the sim to find out the repercussions !
Easy on the language, cowboy.

I agree that MCAS needs to be redesigned to be dual sensor, less aggressive and limited to a smaller, maximum angle.

But a single point of failure is nothing new to aircraft. Engine failures and a window blowing out are also single point of failures. That's why there are emergency procedures including those that must be memorized.

The Ethiopian pilots knew about MCAS - explain to me why they didn't do the UAS drill which would have at least allowed them control the aircraft even with MCAS. And how about the stab trim runaway drill for what was by all appearance to be a stab trim runaway.

Pilots are the last line of defense. This event was perfectly manageable just like an engine failure, which is also a single point of failure. But the pilots have to be competent - the Lion Air pilots the day before were, the ones the next day were not. please read the report.
Didn’t they have a third pilot on the jumpseat and he’s the one that suggested they flip the trim cutoff switches? They also didn’t snag the defect if IRC.

Also, I read on here that Boeing still hasn’t submitted the full software package for the MCAS fix and that pilots still pooched it in the sim during testing for the fix.
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Re: Boeing Systemic Problems Continue

Post by Old fella »

Duke Point wrote:
Mon Dec 30, 2019 6:37 am
I gotta agree with L39Guy.

We live in a blameless society when it comes to people. NEVER blame the individual. Look elsewhere.

Memory drills were forgotten, ignored, or done incorrectly. Yes MCAS V.1 was poorly designed, but the 737's in question were NEVER uncontrollable.

Memory drills are memory drills for a reason, and these crashes --would not have occurred--- if the proper memory drills had been followed. Unfortunately this valuable lesson will likely be lost in the media firestorm, and sloppy pilots will continue to make fundamental errors.

DP.
To this uninformed bystander on all things B737 and airlines, I never heard nor read anything on this side of the airline earth about the MCAS getting out of hand. If there were such incidents no ‘37s went screaming(literally and figuratively) head first into the ground at a great number of kts, that would say to me training and execution of required memory drills were appropriately attended to. Just asking!
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corethatthermal
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Re: Boeing Systemic Problems Continue

Post by corethatthermal »

Pilots are the last line of defense. This event was perfectly manageable just like an engine failure, which is also a single point of failure. But the pilots have to be competent - the Lion Air pilots the day before were, the ones the next day were not. please read the report.
I agree The pilots were ALSO at fault ,,,,Boeing first, then the pilots . The plane, as configured , should have never made it into pilots hands, let alone incompetent ones ! BTW, Where is the NG switch that only shut -off the Automatic trim systems but allowed the yoke trim to work ?
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L39Guy
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Re: Boeing Systemic Problems Continue

Post by L39Guy »

TFTMB heavy wrote:
Mon Dec 30, 2019 6:52 am
Didn’t they have a third pilot on the jumpseat and he’s the one that suggested they flip the trim cutoff switches? They also didn’t snag the defect if IRC.

Also, I read on here that Boeing still hasn’t submitted the full software package for the MCAS fix and that pilots still pooched it in the sim during testing for the fix.
There is no mention in the Indonesian report of a jumpseater telling them to turn off the stab trim on the incident flight.

Don't believe everything you read on here; my guess that everything has been redesigned, tested and submitted by now as there is huge pressure to get it done.
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Re: Boeing Systemic Problems Continue

Post by L39Guy »

corethatthermal wrote:
Mon Dec 30, 2019 9:23 am
Pilots are the last line of defense. This event was perfectly manageable just like an engine failure, which is also a single point of failure. But the pilots have to be competent - the Lion Air pilots the day before were, the ones the next day were not. please read the report.
I agree The pilots were ALSO at fault ,,,,Boeing first, then the pilots . The plane, as configured , should have never made it into pilots hands, let alone incompetent ones ! BTW, Where is the NG switch that only shut -off the Automatic trim systems but allowed the yoke trim to work ?
If you would read the Indonesian report, you will see that blame is allocated to Boeing, FAA, the outfit that overhauls these AOA probes, the Indonesian regulator, Lion Air, the contract maintenance outfit that "fixed" the problem after the incident flight and finally the pilots. Lots of blame to go around.
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Re: Boeing Systemic Problems Continue

Post by L39Guy »

It is interesting and sad how times have changed, particularly with the social media frenzy.

There were two fatal B737 accidents in the US, United 585 in Colorado Springs in 1991 and US Air 427 in Pennsylvania in 1994, both of which were determined to be caused by a defective rudder actuator that would go hard over for no apparent reason. Unlike the MCAS issue, it took a long, long time to figure out what caused the accident and even longer to fix the problem with new actuators.

Yet, in the 1990's the B737's kept on flying with crews being alerted to the issue, its symptoms and reminded of the recovery actions. Every B737 out there was a ticking time bomb but the risk was accepted as it was felt that trained crews could manage the situation. And there were thousands of B737's affected by this.

Fast forward twenty five years. An entire sub-fleet of the B737 is grounded over an issue that was known shortly after the first accident, was known immediately after the second accident, it has been demonstrated that the aircraft is flyable by line pilots with this condition by trained pilots (Lion Air incident flight) and no special procedures or training is required because the response in an MCAS event is simple, well known, memory emergency drills.

The treatment of the MAX has got to be more than just a fix of the MCAS. Surely there are other political (FAA spanking Boeing), geopolitical (China sticking it to the US/Trump), competitive (Airbus vs Boeing), media (conventional and sensationalism) and social media issues at play.
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Curiousflyer
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Re: Boeing Systemic Problems Continue

Post by Curiousflyer »

L39Guy wrote:
Mon Dec 30, 2019 10:30 am
It is interesting and sad how times have changed, particularly with the social media frenzy.

There were two fatal B737 accidents in the US, United 585 in Colorado Springs in 1991 and US Air 427 in Pennsylvania in 1994, both of which were determined to be caused by a defective rudder actuator that would go hard over for no apparent reason. Unlike the MCAS issue, it took a long, long time to figure out what caused the accident and even longer to fix the problem with new actuators.

Yet, in the 1990's the B737's kept on flying with crews being alerted to the issue, its symptoms and reminded of the recovery actions. Every B737 out there was a ticking time bomb but the risk was accepted as it was felt that trained crews could manage the situation. And there were thousands of B737's affected by this.

Fast forward twenty five years. An entire sub-fleet of the B737 is grounded over an issue that was known shortly after the first accident, was known immediately after the second accident, it has been demonstrated that the aircraft is flyable by line pilots with this condition by trained pilots (Lion Air incident flight) and no special procedures or training is required because the response in an MCAS event is simple, well known, memory emergency drills.

The treatment of the MAX has got to be more than just a fix of the MCAS. Surely there are other political (FAA spanking Boeing), geopolitical (China sticking it to the US/Trump), competitive (Airbus vs Boeing), media (conventional and sensationalism) and social media issues at play.
The MCAS response is not simple. It’s incredibly complex and difficult to diagnose amongst the many bells and whistles going off.
https://theaircurrent.com/aviation-safe ... ax-return/

“During the recent pilot trials, which tested how crews react to various scenarios involving the revised 737 Max flight control software and new checklists, all the pilots managed to get themselves out of trouble, but Boeing and regulators found that “more than half…of pilots responded with the wrong procedures,” ”
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Re: Boeing Systemic Problems Continue

Post by boeingboy »

“During the recent pilot trials, which tested how crews react to various scenarios involving the revised 737 Max flight control software and new checklists, all the pilots managed to get themselves out of trouble, but Boeing and regulators found that “more than half…of pilots responded with the wrong procedures,” ”
Yes - I read the same thing....but you have to keep an open mind as there are too few details. Such as what procedures did they use and at what time, why did they do that, and what were the actual issues.

The main takeaway here is that even though they applied the incorrect procedures - they all were able to recover the aircraft. That itself speaks volumes about the re-design itself.
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boeingboy
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Re: Boeing Systemic Problems Continue

Post by boeingboy »

I agree The pilots were ALSO at fault ,,,,Boeing first, then the pilots . The plane, as configured , should have never made it into pilots hands, let alone incompetent ones ! BTW, Where is the NG switch that only shut -off the Automatic trim systems but allowed the yoke trim to work ?
You should do less yapping and more learning.

As someone who is not a pilot and has no knowledge of aircraft design, engineering or operation....you should be listening and asking intelligent questions from those more experienced. As has been said before - the switches to disable the trim system on the 737 and pretty much all other Boeing airplanes are located on the center pedestal - just to the right of the fuel cutoff switches. Well within easy reach of either pilot.

As for the configuration - single point failures happen. They have happen many times before. Just familiarize yourself with Turkish Airlines 1951. Yes it was a single point failure - but it was the inattention of the crew that doomed the plane.

It is very interesting to learn just how and why MCAS morphed into what it is now. Boeing didn't intentionally design it badly, and the thing that sticks out to me is that they actually had protections built in so you could shut it off. Airbus never did that. If it faults - you ride It into the ground - unless the aircraft decides to give control back to you (Qantas Flight 72) ((Yes - there are new procedures now))

Boeing must share some of the blame for the accident - but as I have maintained since day one - even with that failure, the aircraft was not unrecoverable.
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Re: Boeing Systemic Problems Continue

Post by plausiblyannonymous »

L39Guy wrote:
Mon Dec 30, 2019 10:30 am
It is interesting and sad how times have changed, particularly with the social media frenzy.

There were two fatal B737 accidents in the US, United 585 in Colorado Springs in 1991 and US Air 427 in Pennsylvania in 1994, both of which were determined to be caused by a defective rudder actuator that would go hard over for no apparent reason. Unlike the MCAS issue, it took a long, long time to figure out what caused the accident and even longer to fix the problem with new actuators.

Yet, in the 1990's the B737's kept on flying with crews being alerted to the issue, its symptoms and reminded of the recovery actions. Every B737 out there was a ticking time bomb but the risk was accepted as it was felt that trained crews could manage the situation. And there were thousands of B737's affected by this.

Fast forward twenty five years. An entire sub-fleet of the B737 is grounded over an issue that was known shortly after the first accident, was known immediately after the second accident, it has been demonstrated that the aircraft is flyable by line pilots with this condition by trained pilots (Lion Air incident flight) and no special procedures or training is required because the response in an MCAS event is simple, well known, memory emergency drills.

The treatment of the MAX has got to be more than just a fix of the MCAS. Surely there are other political (FAA spanking Boeing), geopolitical (China sticking it to the US/Trump), competitive (Airbus vs Boeing), media (conventional and sensationalism) and social media issues at play.
I understand the point you are making, but you are failing to account for Boeing's actions in 2009 vs 1991.

Boeing made a choice to have critical flight control software be affected by a single AoA sensor. It was a choice to save money and it backfired. They were shown to have cheated the system and now they are facing the consequences.

The rudder control failure was a malfunction that could not have been foreseen.
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Re: Boeing Systemic Problems Continue

Post by corethatthermal »

As someone who is not a pilot and has no knowledge of aircraft design, engineering or operation
Maybe YOU are the armchair wannabe , Please answer the below information Boeing boy


The Boeing 737 NG has stabilizer trim cutout switches marked as MAIN ELECT (left) and AUTOPILOT (right). Turning off the right switch disables automatic stabilizer trim in autopilot mode and automatic stabilizer trim by the STS in manual mode. The stabilizer can still be trimmed with electric trim switches on the control wheel or manually with the hand crank. Turning off the left switch disables the electric trim on the control wheel.
The Boeing 737 MAX has stabilizer cutout switches marked as PRI (left) and B/U (right).

With the MAX, Boeing added MCAS to the existing STS functionality. If Boeing kept the cutoff switches functionality intact, then turning off the right switch would disable both STS and MCAS, keeping the electric trim operable. Instead, in case of misbehaving MCAS Boeing requires to cut off BOTH switches without explaining what each of the switches does. With both switches turned off the only option to change stabilizer trim is to use a hand crank.

What do you know, I found the answer to my exact question in the Seattle Times:

First of all, even after two fatal crashes,

Boeing declined to detail the specific functionality of the two switches.

Nevertheless,

The Seattle Times found that the left switch on the 737 NG model is capable of deactivating the buttons on the yoke that pilots regularly press with their thumb to control the horizontal stabilizer. The right switch on the 737 NG is capable of deactivating just the automated controls of the stabilizer.

So far this corresponds to the information I found in the 737 NG FCOM myself.

As Boeing was transitioning from its 737 NG model to the 737 MAX, the company altered the labeling and the purpose of those two switches.

On the newer 737 MAX, according to documents reviewed by The Times, those two switches were changed to perform the same function – flipping either one of them would turn off all electric controls of the stabilizer. That means there is no longer an option to turn off automated functions – such as MCAS – without also turning off the thumb buttons the pilots would normally use to control the stabilizer.

If the above is correct, then not only MCAS, but STS/autopilot as well cannot be turned off on the MAX while keeping electric trim on the control wheel functional.

Peter Lemme, a former Boeing flight-controls engineer, said if the company had maintained the switch design from the 737 NG, Boeing could have instructed pilots after the Lion Air crash last year to simply flip the “AUTO PILOT” switch to deactivate MCAS and continue flying with the normal trim buttons on the control wheel.

(^ bold is mine). This is exactly what I was alluding to in my question. I really want to hear the reasons for the change.

Lemme said he’s surprised that Boeing made the change to take away the functionality that could have allowed the pilots to shut off MCAS without shutting off the electric switches at their thumbs.

Oops.
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Re: Boeing Systemic Problems Continue

Post by L39Guy »

plausiblyannonymous wrote:
Mon Dec 30, 2019 6:15 pm
L39Guy wrote:
Mon Dec 30, 2019 10:30 am
It is interesting and sad how times have changed, particularly with the social media frenzy.

There were two fatal B737 accidents in the US, United 585 in Colorado Springs in 1991 and US Air 427 in Pennsylvania in 1994, both of which were determined to be caused by a defective rudder actuator that would go hard over for no apparent reason. Unlike the MCAS issue, it took a long, long time to figure out what caused the accident and even longer to fix the problem with new actuators.

Yet, in the 1990's the B737's kept on flying with crews being alerted to the issue, its symptoms and reminded of the recovery actions. Every B737 out there was a ticking time bomb but the risk was accepted as it was felt that trained crews could manage the situation. And there were thousands of B737's affected by this.

Fast forward twenty five years. An entire sub-fleet of the B737 is grounded over an issue that was known shortly after the first accident, was known immediately after the second accident, it has been demonstrated that the aircraft is flyable by line pilots with this condition by trained pilots (Lion Air incident flight) and no special procedures or training is required because the response in an MCAS event is simple, well known, memory emergency drills.

The treatment of the MAX has got to be more than just a fix of the MCAS. Surely there are other political (FAA spanking Boeing), geopolitical (China sticking it to the US/Trump), competitive (Airbus vs Boeing), media (conventional and sensationalism) and social media issues at play.
I understand the point you are making, but you are failing to account for Boeing's actions in 2009 vs 1991.

Boeing made a choice to have critical flight control software be affected by a single AoA sensor. It was a choice to save money and it backfired. They were shown to have cheated the system and now they are facing the consequences.

The rudder control failure was a malfunction that could not have been foreseen.
In retrospect, perhaps there should be dual input. I suppose its easy to second guess engineers and test pilots after these accidents and say "I told you so". Engineering and design involves choices and compromises based upon cost, ease of implementation, weight, complexity, etc.

Boeing made a mistake with the NG when they used a single source of radar altimetry which turned out to be the cause of the Turkish accident at Schipol. Now it is a dual installation - I suppose they assumed how could two pilots (in the Turkish case, three) could possibly not notice the throttles going to idle hundreds and thousands of feet in the air, let alone not notice the speed decay to the stall.

Airbus never contemplated someone flying into a thunderstorm in the ITCZ where the rate of ice accretion exceeding the heating capabilities of the probes. Nor did they anticipate a situation where one pilot is pulling back and the other pushing forward on the joystick (AF 447) with the aircraft getting into a deep stall.

ATR never anticipated pilots shutting down the wrong engine shortly after take-off (Taipei).

And finally, Boeing never thought that professional airline pilots type rated on the B737 could not hand fly the aircraft - i.e. manually trim the aircraft with the thumb switch (thus shutting off MCAS), pulling the power levers out of take-off power to at least a climb or cruise setting so they were not racing around at Vne and trying to use the manual trim wheel. Boeing never thought that professional airline pilots type rated on the B737 could not recognize an unreliable airspeed condition let alone do the (very) simple drill. Boeing never thought that professional airline pilots type rated on the B737 could not, after 26 trim runaways, not turn of the stab trim using the cut-out switches.

Use your imagination and think of the wildest, most ridiculous situation of pilot incompetence and now design an aircraft that will be crash proof. Good luck doing that with a cost and weight that would allow the aircraft to fly.
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