UPDATE
Investigators at the crash site of the doomed Ethiopian Airlines flight have found new evidence that points to another connection to the earlier disaster involving the same Boeing jet.

The evidence, a piece of the Boeing 737 Max 8 jet that crashed in Ethiopia last weekend killing 157 people, suggests that the plane’s stabilizers were tilted upward, according to two people with knowledge of the recovery operations. At that angle, the stabilizers would have forced down the nose of the jet, a similarity with the Lion Air crash in October.

The causes of both crashes are still under investigation, but the new evidence potentially indicates that the two planes both had problems with a newly installed automated system on the 737 Max jet intended to prevent a stall.

https://www.nytimes.com/2019/03/15/busi ... crash.html

Interested wrote:

osiris30 wrote:

N14AZ wrote:

Wow, I really hope no one of the ET crash victim’s families will read this statement.

Why? Because it is logical. Good grief. Everyone is falling all over themselves. This thread is discussing an accident. Accidents need to be dissected in a logical manner, not an emotional one. Emotional dissections lead to biases. Biases lead to erroneous decisions and data favoring. The families of the people on BOTH ET and JT flights have my most sincere condolences, as do the families of the folks on the Atlas '67, as do the families of the folks in NZ this morning. Condolences don't do jack squat to make anything safer or better. Calling out a false assumption is not some horrible heartless act as much as people here like to think it is when they climb aboard their trusty tall steed of moral righteousness.

The statement is 100% true because: There is NOT ONE single piece of man-made equipment on the planet that is PERFECT. Every aircraft has errors, so does every car, building, bridge, toaster, fridge, stove, lightbulb, etc. It does NOT (in and of itself) make them unsafe. If you can't grasp that, perhaps this thread isn't the one for you. The poster I was replying to was conflating imperfection with unsafe. That was and still is a false assumption and I called them on it.

Boeings wording for the software upgrade they've been working on since the Lion crash is:

the upgrade is designed “to make an already safe aircraft safer”.

I'm going to suggest they've had to be very careful when choosing those words

And I'm going to suggest they are biased

And I'm going to suggest that by the standards we expect plane makers to set the actual wording should be

"To make an unsafe aircraft safer"

This plane clearly wasn't and still isn't safe to the level Boeing or any other plane maker would expect?

Do you disagree?

Boeing won't admit it. But its out of their hands now anyway.

Well surely they're biased. To me it's both some bravado as well as a mild shot at those that think it's unsafe.

Interested wrote:

The exact same plane that isn't safe to fly now wasn't safe to fly in October when it first crashed. Boeing became aware it wasn't safe in November at the latest. If not before.

Not safe to fly with 200 hour pilots. But any transport jet is unsafe with a 200 hour pilot.

If the captain made the distress call does that mean the FO was flying? Or was the captain effectively single pilot and making his own errors that went unchecked by a inexperienced co pilot

osiris30 wrote:

but I won't delude myself into thinking we are somehow less fallible than we were 20-30 years ago. The only difference is the level of arrogance has increased many-fold to the point where we THINK we are so much better than we used to be.

Math and science test scores, in the US, would argue we are MORE fallible than 20-30 years ago.

enilria wrote:

UPDATE
Investigators at the crash site of the doomed Ethiopian Airlines flight have found new evidence that points to another connection to the earlier disaster involving the same Boeing jet.

The evidence, a piece of the Boeing 737 Max 8 jet that crashed in Ethiopia last weekend killing 157 people, suggests that the plane’s stabilizers were tilted upward, according to two people with knowledge of the recovery operations. At that angle, the stabilizers would have forced down the nose of the jet, a similarity with the Lion Air crash in October.

The causes of both crashes are still under investigation, but the new evidence potentially indicates that the two planes both had problems with a newly installed automated system on the 737 Max jet intended to prevent a stall.

https://www.nytimes.com/2019/03/15/busi ... crash.html

Or that as per my conjecture the aircraft left the ground mistrimmed and was never corrected.

Eagerly awaiting the FDR data. If we see the grounding lifted in a couple of days we will know why.

N212R wrote:

osiris30 wrote:

but I won't delude myself into thinking we are somehow less fallible than we were 20-30 years ago. The only difference is the level of arrogance has increased many-fold to the point where we THINK we are so much better than we used to be.

Math and science test scores, in the US, would argue we are MORE fallible than 20-30 years ago.

I won't argue that for a second. Hell I have seen countless people that cannot make change without an electronic device. This is basic stuff that never used to be a problem.

Varsity1 wrote:

YoungDon wrote:

Varsity1 wrote:

So the first officer had 200 hours? This was probably his first flight flying a jet of any kind. I would suspect a loss of control.

That's definitely not the case, training programs in foreign countries start out with cadets with no time flown beginning on jets. He's definitely inexperienced, but it's entirely possible all of his flight time is in jets.

What will be interesting to know is the amount of time he had on the MAX.

You don't spend your first 200 hours learning in jets anywhere on earth except some militaries.

Even if he had 200 hours all in the 737 max, it's almost nothing for flight time. Most pilots fly 100 hours a month!

Something I feel needs to be clarified is if these 200 hours are total time, or time in jets.

VS11 wrote:

How soon apart were the two crashed MAXes built? Who is the manufacturer of the pitot tubes and the AOA indicators? MCAS may have its issues and like all software it is work in progress - wouldn’t be surprised if Boeing was working on newer versions even before Lion Jet. However, there is this serious issue of low quality components being installed on jets. Does Boeing or Airbus test these component before installed?

That's what I've been wondering. What if this turns out to be a manufacturing quality issue,
perhaps a batch of faulty AOA indicators or heck, maybe some bad wiring installations?

There was plenty of discussion how hard the workers were scrambling to adjust to
the higher build rate at the Renton factory. Something could have fallen thru the cracks
in their rush to catch up to the breakneck build rate

Sooner787 wrote:

VS11 wrote:

How soon apart were the two crashed MAXes built? Who is the manufacturer of the pitot tubes and the AOA indicators? MCAS may have its issues and like all software it is work in progress - wouldn’t be surprised if Boeing was working on newer versions even before Lion Jet. However, there is this serious issue of low quality components being installed on jets. Does Boeing or Airbus test these component before installed?

That's what I've been wondering. What if this turns out to be a manufacturing quality issue,
perhaps a batch of faulty AOA indicators or heck, maybe some bad wiring installations?

There was plenty of discussion how hard the workers were scrambling to adjust to
the higher build rate at the Renton factory. Something could have fallen thru the cracks
in their rush to catch up to the breakneck build rate

Manufacturing issues for Boeing and the 737 won’t be happening for the first time. Very engaging even if somewhat disturbing article from a few years ago:
Newsweek: Is Boeing 737 an airplane prone to problems

https://www.newsweek.com/boeings-737-ai ... lems-63629

Way too much speculation going on from people without the proper expertise and hard facts from scene. Why can't we say "we don't know at this point??

osiris30 wrote:

As time has gone on I have continued to flesh out what *I* feel the chain of events is and to my mind now it starts before the take-off roll:

1) Either on prior flight or before commencing this flight; pilots of last flight or this flight disable MCAS as a precatuion (stab cut-off)
2) PIlots of this flight miss (or knew it was off), but fail to trim plane correctly.

What is your background? Are you in the airlines and/or a Boeing pilot? Granted I have not worked for the airlines, and I am not currently a MAX pilot (but I did fly 737-800s for a few years) and I have a VERY hard time believing what you are so sure or here

1: the previous pilots that supposedly got this malfunction and threw off the stab switches didn't relay this info to maintenance and/or maintenance didn't relay this info to the pilots/it wasn't seen in the write ups?

2: what do you mean "disable MCAS as a precaution?" As in they had flight control problems or uncommanded nose drops and switched the stab cutoff switches? That would make it even more unbelievable they simply forgot to tell maintenance/maintenance didn't immediately ground the plane/didn't tell this crew/this crew missed the write up? Or do you mean they disabled it "just in case"?

It's been a couple years since I flew the 737 but I'm 99.5% sure that would disable MCAS........ but also the pilots' electric trim and autopilot leaving you with only the obnoxious wheel. I have a hard time believing they would go through all that or if the airline's SOP would even allow that

3: then you say the mishap crew perhaps "missed" that the stab cutoff switches were off? Did they miss the write up that undoubtedly would have existed? Did they also just overlook these switches being set incorrectly in their cockpit flows/checklists? Did they also not set takeoff trim in the green band, something you also hit in the checklist before every flight or was it already coincidentally in the green band?

Or "they knew it was off," I'd be surprised if ET lets their pilots takeoff with these switches tripped or the pilots did it on their own accord, could be wrong but that does not sound right at all.

On top of all that, all that stuff that would draw their attention to trim, they fail to set it correctly? It's not some complex equation or something rarely done, you get the trim calculated out every single flight and it should fall in the green band


I'm not saying all that is impossible but it doesn't pass the sniff test. I'd say you should go back to the drawing board... but why? Why over speculate and come up with an answer? There are way too many unknowns, I as a former 737 pilot wouldn't feel comfortable speculating off the very little info we have, why can't we just say "we don't know" and wait for more info?

The speculation doesn't help much and makes us all talk in circles. The level of certainty you exhibited makes it even worse

But maybe I misunderstood your points or you have a lot more expertise in the area, maybe ET does things a lot differently than I'd imagine (if what you outlined is the case I'd say they're extremely incompetent)

What worries me is all those who keep saying ”a pilot not knowing about this issue has been in a cave for 4 months”, ”it’s a training issue”, ”it’s because the F/o had 200 hours” etc. A plane should not fly itself into the ground, switch flicked off or not.

JohnKrist wrote:

What worries me is all those who keep saying ”a pilot not knowing about this issue has been in a cave for 4 months”, ”it’s a training issue”, ”it’s because the F/o had 200 hours” etc. A plane should not fly itself into the ground, switch flicked off or not.

But according to some that know how it feels when SHTF it might be a factor.

https://www.foxnews.com/us/hero-pilot-w ... ines-crash

JohnKrist wrote:

What worries me is all those who keep saying ”a pilot not knowing about this issue has been in a cave for 4 months”, ”it’s a training issue”, ”it’s because the F/o had 200 hours” etc. A plane should not fly itself into the ground, switch flicked off or not.

Sully's right about this..... a copilot with only 200 hrs ?????

That's ludicrous.

I watched a documentary about QF32 and it showed how a flight deck
manned by very experienced pilots were able to work seamlessly as a team,
to the point of knowing when not to follow the book , to safely land that big bird
back in SIN and save everyone on board.

JohnKrist wrote:

What worries me is all those who keep saying ”a pilot not knowing about this issue has been in a cave for 4 months”, ”it’s a training issue”, ”it’s because the F/o had 200 hours” etc. A plane should not fly itself into the ground, switch flicked off or not.

Such as AF 447 doing so from all the way up at cruise altitude?

IIRC the remedy for the A330 was replacing the defective part (pitot) and improved pilot training.

Are you as equally unhappy with the A330 situation?

JohnKrist wrote:

What worries me is all those who keep saying ”a pilot not knowing about this issue has been in a cave for 4 months”, ”it’s a training issue”, ”it’s because the F/o had 200 hours” etc. A plane should not fly itself into the ground, switch flicked off or not.

See, it is as simple as this - BOEING SCREWED UP. There is no point in people arguing - plane was grounded due to social media pressure; pilot training problem; F/O has only 200 hours etc. etc. It doesn't get simpler than this.

It is as simple as Mercedes, BMW or Toyota putting in a feature where, it accelerates the car when you hit the brake pedal and people arguing that the driver did not have enough experience or should have flipped some switches to disconnect that feature!!!! Boeing put in some crap that wasn't well thought out; wasn't well documented and wasn't well communicated. Larger question is how was this certified? That is the bigger question arising from the 787 battery fire and the 737 flight control software issue debacles. These issues should never have gotten past the certification process if it were stringent.

JohnKrist wrote:

What worries me is all those who keep saying ”a pilot not knowing about this issue has been in a cave for 4 months”, ”it’s a training issue”, ”it’s because the F/o had 200 hours” etc. A plane should not fly itself into the ground, switch flicked off or not.

Any plane left unsupervised will fly itself into the ground.

dragon6172 wrote:

JohnKrist wrote:

What worries me is all those who keep saying ”a pilot not knowing about this issue has been in a cave for 4 months”, ”it’s a training issue”, ”it’s because the F/o had 200 hours” etc. A plane should not fly itself into the ground, switch flicked off or not.

Any plane left unsupervised will fly itself into the ground.

Well, this plane wasn’t really unsupervised, was it?

gensys wrote:

JohnKrist wrote:

What worries me is all those who keep saying ”a pilot not knowing about this issue has been in a cave for 4 months”, ”it’s a training issue”, ”it’s because the F/o had 200 hours” etc. A plane should not fly itself into the ground, switch flicked off or not.

Such as AF 447 doing so from all the way up at cruise altitude?

IIRC the remedy for the A330 was replacing the defective part (pitot) and improved pilot training.

Are you as equally unhappy with the A330 situation?

I didn’t mention A or B, I simply stated that a plane should not fly itself into the ground. I don´t care who glued/riveted the thing together...

gensys wrote:

JohnKrist wrote:

What worries me is all those who keep saying ”a pilot not knowing about this issue has been in a cave for 4 months”, ”it’s a training issue”, ”it’s because the F/o had 200 hours” etc. A plane should not fly itself into the ground, switch flicked off or not.

Such as AF 447 doing so from all the way up at cruise altitude?

IIRC the remedy for the A330 was replacing the defective part (pitot) and improved pilot training.

Are you as equally unhappy with the A330 situation?

After the AP disengaged the aircraft pretty much informed the pilots that it was now up to them to continue flying with following results (from BEA final report):

- the crew made inappropriate control inputs that destabilized the flight path
- the crew failed to follow appropriate procedure for loss of displayed airspeed information
- the crew were late in identifying and correcting the deviation from the flight path
- the crew lacked understanding of the approach to stall
- the crew failed to recognize the aircraft had stalled and consequently did not make inputs that would have made it possible to recover from the stall

JohnKrist wrote:

dragon6172 wrote:

JohnKrist wrote:

What worries me is all those who keep saying ”a pilot not knowing about this issue has been in a cave for 4 months”, ”it’s a training issue”, ”it’s because the F/o had 200 hours” etc. A plane should not fly itself into the ground, switch flicked off or not.

Any plane left unsupervised will fly itself into the ground.

Well, this plane wasn’t really unsupervised, was it?

Neither was AF447

dragon6172 wrote:

JohnKrist wrote:

dragon6172 wrote:

Any plane left unsupervised will fly itself into the ground.

Well, this plane wasn’t really unsupervised, was it?

Neither was AF447

Point being?

Hello everyone, my first post. I am no pilot or engineer but an aviation fan and a business consultant (including a few airlines). Although I understand most of the technical staff, commenting on them is beyond me. I will try to summarize my views from a business angle.

The aircraft is grounded on the basis that it was unsafe. So unsafe that people don't let it fly over their airspace.

We do not know what caused the accidents. However, the public opinion is that the aircraft is crippled and Boeing is trying to keep it airborne with a band aid called MCAS which is also crippled. Very difficult to change that perception even it is proved otherwise. In the eyes of the public, I mean. I would never ride on that tube, would you?

It is not going to be like "we upgraded the software, let's fly". Certification will take ages. Given its credibility, FAA's decision is not enough, European authorities and Asians should be convinced, as well. Do not miss the delicate point that Lufthansa said "June", therefore, set a tentative time frame. They can extend it, but bring it forward is highly unlikely. The interesting thing is despite the fact that Lufthansa is a major Boeing customer, they do not have a single max and they have not ordered one. On the other hand, they are the big brother of star alliance capable of imposing on other members.

The cost of grounding is estimated to be 1.5 to 2.5 billion dollars a month to Boeing. I do not know who made the calculation but the total cost is estimated to be 7 billion minimum, assuming that things will go smooth after this period. Given the revenues generated from delivered aircraft, it is like 20% discount that you can live with. However, Boeing lost face. There are a number of airlines deeply involved in this. Fly Dubai has a current fleet of 60 aircraft (10 of which is max) and they have pending orders of max totaling to 240. One example only, there are many. Some of these orders are optional. Boeing is about to forget them. Look at wiki for "List of Boeing 737 MAX orders and deliveries". You will see the numbers, if you click on the airline with massive orders you can check their current fleets for dependency.

Good news for Boeing is, max case proved that depending on one manufacturer is not good. Bad news is, the competitor is flying.

IMO, max is a child who is unlikely to reach puberty.

A number of airlines seem to be going down with the max project. Boeing should come up with a solution like feeding them with NGs at a good discount and develop a new aircraft for this market rapidly but not in rush.

.

DeltaMD90 wrote:

Way too much speculation going on from people without the proper expertise and hard facts from scene. Why can't we say "we don't know at this point??

osiris30 wrote:

As time has gone on I have continued to flesh out what *I* feel the chain of events is and to my mind now it starts before the take-off roll:

1) Either on prior flight or before commencing this flight; pilots of last flight or this flight disable MCAS as a precatuion (stab cut-off)
2) PIlots of this flight miss (or knew it was off), but fail to trim plane correctly.

What is your background? Are you in the airlines and/or a Boeing pilot? Granted I have not worked for the airlines, and I am not currently a MAX pilot (but I did fly 737-800s for a few years) and I have a VERY hard time believing what you are so sure or here

1: the previous pilots that supposedly got this malfunction and threw off the stab switches didn't relay this info to maintenance and/or maintenance didn't relay this info to the pilots/it wasn't seen in the write ups?

2: what do you mean "disable MCAS as a precaution?" As in they had flight control problems or uncommanded nose drops and switched the stab cutoff switches? That would make it even more unbelievable they simply forgot to tell maintenance/maintenance didn't immediately ground the plane/didn't tell this crew/this crew missed the write up? Or do you mean they disabled it "just in case"?

It's been a couple years since I flew the 737 but I'm 99.5% sure that would disable MCAS........ but also the pilots' electric trim and autopilot leaving you with only the obnoxious wheel. I have a hard time believing they would go through all that or if the airline's SOP would even allow that

3: then you say the mishap crew perhaps "missed" that the stab cutoff switches were off? Did they miss the write up that undoubtedly would have existed? Did they also just overlook these switches being set incorrectly in their cockpit flows/checklists? Did they also not set takeoff trim in the green band, something you also hit in the checklist before every flight or was it already coincidentally in the green band?

Or "they knew it was off," I'd be surprised if ET lets their pilots takeoff with these switches tripped or the pilots did it on their own accord, could be wrong but that does not sound right at all.

On top of all that, all that stuff that would draw their attention to trim, they fail to set it correctly? It's not some complex equation or something rarely done, you get the trim calculated out every single flight and it should fall in the green band


I'm not saying all that is impossible but it doesn't pass the sniff test. I'd say you should go back to the drawing board... but why? Why over speculate and come up with an answer? There are way too many unknowns, I as a former 737 pilot wouldn't feel comfortable speculating off the very little info we have, why can't we just say "we don't know" and wait for more info?

The speculation doesn't help much and makes us all talk in circles. The level of certainty you exhibited makes it even worse

But maybe I misunderstood your points or you have a lot more expertise in the area, maybe ET does things a lot differently than I'd imagine (if what you outlined is the case I'd say they're extremely incompetent)

Thanks for the straightening the facts out.

mcdu wrote:

Interested wrote:

The exact same plane that isn't safe to fly now wasn't safe to fly in October when it first crashed. Boeing became aware it wasn't safe in November at the latest. If not before.

Not safe to fly with 200 hour pilots. But any transport jet is unsafe with a 200 hour pilot.

200 something hours was legal in the US upto 2013.
( and introduced to compensate for lack of experience linked to crew that had 2..4000hours. hilarious.)

No significant change in irregularities in the US space were these changes had effect.
So you better get off your high 1500h horse here.

IMU the 1500 hours rule was a stealth hitch up for military pilots ( who, strangely, go for 750 hours min if they go civil.)

Finn350 wrote:

Based on the current information, the defective AoA vane is definitely a contributing factor.

Based on the current information faulty AoA data handed to MCAS is a contributing factor.

Note the difference.

Data path is Sensors -> ADIRU -> MCAS
logged data in the FDR is apparently ADIRU output and not AoA output.

smartplane wrote:

estorilm wrote:

For 50 years, normal stall recovery procedures were perfectly adequate on prior aircraft, even when it came time to certify the NG. For some reason, that's not the case with the MAX. It's not really a "feature" Boeing added as an upgrade with the new plane or something - it's a requirement for certification.

It's a feature Boeing added to perpetuate grandfathering. It is a requirement for certification, in order to mimic, within approved tolerances, the flight behaviour of the NG.

The MAX, within approved tolerances mimics the NG. The NG, within tolerances mimics the Classic. The Classic, within approved tolerances, mimics the 100/200. But the ultimate parent is the 100/200, which after applying multiple layers of tolerances, bears little or no resemblance to the flight behaviour of the MAX, even with electronic cloaking to make it seem so.

What you're describing is the logical endpoint of a once-vibrant American (and global) aircraft-manufacturing industry which narrowed itself, at least in the Western world, to a duopoly and - in the USA - a monopoly. Monopolies create certain efficiencies but also certain dangers. The freight train of the MAX program carried a lot of momentum. It still does. Dang good chance that a flawed aircraft, which may actually not be fixable, still gets rammed down everyone's throats, instead of actually killing the program.

I have no animus to Boeing at all. Great company, with huge historical success and legendary contribution to aviation. Boeing may be the only company that can survive flat-out scrapping an aircraft type.

Before I get crowd-attacked, let me ask this:

Can the landing gear be made longer to accommodate moving the engines backward and eliminate the drag issue underlying this whole fiasco? I don't think so, due to width of the fuselage and the spacing of the engine pylons.

Can a telescoping landing gear be designed that would accommodate the width of the fuselage and the spacing of the engine pylons.... maaaaaaaaaaaaybe.

Can the airliner be made as safe as the NG in its current configuration, even with software fixes? ......... hmmmmm

Is this fair to the pilots and crew, not to mention the traveling public, as we get forced to fly the MAX for the next 25 years? .......hmmmmmmm

Does an entire globe-full of airlines keep up 5,000 orders for a plane that strongly appears to be a safety retrogression? In our current political state of "no rules" and disrespect for the rule of law .... ????????

This is a very ugly moment, for sure.

Why not putting an 200hrs pilot on an already save Plane, that was made even saver?

hivue wrote:

trnswrld wrote:

danj555 wrote:

Couldn't the pilots in any case of malfunction just turn off all electronic bs? Like you're a pilot. You know how to fly a plane. You have flown thousands of take-offs. You know the right speed, right angle, right altitude. You know how to do it without electronic interference if need be.

So why not hit the kill switch if the computer is having a fit?

I asked this exact question many pages ago. It got pretty much no response. Big problems in IMC is one thing, but to not be able to fly an airplane in clear blue VMC daylight conditions just baffles me....computer issues or not. How does this happen? Look out the window.....fly the airplane FIRST, then figure what the heck is going on. I know easier said than done.

Killing all computers operating on an airplane would have the same effect as killing all computer chips that are operating in your car while you're driving (assuming you are not driving a Stone Age car).

Wouldn't it be more like turning off the lane assist, or cruise control, or accident avoidance instead of driving the car without electricity?

Turning off different autopilot systems and turning off all electronics are two different things.

gensys wrote:

JohnKrist wrote:

What worries me is all those who keep saying ”a pilot not knowing about this issue has been in a cave for 4 months”, ”it’s a training issue”, ”it’s because the F/o had 200 hours” etc. A plane should not fly itself into the ground, switch flicked off or not.

Such as AF 447 doing so from all the way up at cruise altitude?

Firstly, it doesn't matter who built the plane. It shouldn't run intself into the ground/sea with the pilot having no chance to counteract the automatic input.
Secondly, AF447 is a pretty bad example for "driving itself into the ground", because the whole tragedy started with the plane switching to alternate law (i.e. effectively no more automatically triggered manoeuvres) because is correctly detected unreliable airpeed information. From there on, the main input by the crew was to pitch up, even though the stall warning was sounding all the way through.

That accident tells you something about preparing pilots for cases where some automatisms they've become used to suddenly are no longer available (hence the changes to training afterwards). It certainly doesn't tell you anything about an automatic system counteracting pilot input and thus driving the plane into the ground, because that's not what happened on AF447.

anfromme wrote:

From there on, the main input by the crew was to pitch up, even though the stall warning was sounding all the way through.
.

No, the stall warning would shut off at high angles of attack. It would turn on as the nose dropped and the plane could measure airspeed again. So pulling up turned *OFF* the stall warning.

CO953 wrote:

smartplane wrote:

estorilm wrote:

For 50 years, normal stall recovery procedures were perfectly adequate on prior aircraft, even when it came time to certify the NG. For some reason, that's not the case with the MAX. It's not really a "feature" Boeing added as an upgrade with the new plane or something - it's a requirement for certification.

It's a feature Boeing added to perpetuate grandfathering. It is a requirement for certification, in order to mimic, within approved tolerances, the flight behaviour of the NG.

The MAX, within approved tolerances mimics the NG. The NG, within tolerances mimics the Classic. The Classic, within approved tolerances, mimics the 100/200. But the ultimate parent is the 100/200, which after applying multiple layers of tolerances, bears little or no resemblance to the flight behaviour of the MAX, even with electronic cloaking to make it seem so.

What you're describing is the logical endpoint of a once-vibrant American (and global) aircraft-manufacturing industry which narrowed itself, at least in the Western world, to a duopoly and - in the USA - a monopoly. Monopolies create certain efficiencies but also certain dangers. The freight train of the MAX program carried a lot of momentum. It still does. Dang good chance that a flawed aircraft, which may actually not be fixable, still gets rammed down everyone's throats, instead of actually killing the program.

I have no animus to Boeing at all. Great company, with huge historical success and legendary contribution to aviation. Boeing may be the only company that can survive flat-out scrapping an aircraft type.

Before I get crowd-attacked, let me ask this:

Can the landing gear be made longer to accommodate moving the engines backward and eliminate the drag issue underlying this whole fiasco? I don't think so, due to width of the fuselage and the spacing of the engine pylons.

Can a telescoping landing gear be designed that would accommodate the width of the fuselage and the spacing of the engine pylons.... maaaaaaaaaaaaybe.

Can the airliner be made as safe as the NG in its current configuration, even with software fixes? ......... hmmmmm

Is this fair to the pilots and crew, not to mention the traveling public, as we get forced to fly the MAX for the next 25 years? .......hmmmmmmm

Does an entire globe-full of airlines keep up 5,000 orders for a plane that strongly appears to be a safety retrogression? In our current political state of "no rules" and disrespect for the rule of law .... ????????

This is a very ugly moment, for sure.

In the short term, there will be a simple software fix to address the specific MCAS design fault. In the long term, Boeing will replace the 737 with a new clean sheet design. They had been contemplating that already before this debacle, and this is the final push for earnestly starting design work for a clean sheet. There is no point to make additional changes to the 737 frame (it would be adding lipstick over lipstick as some members here call it). Irony here is that as a consequence of these mishaps, A320neo will get a potent rival from Boeing.

JohnKrist wrote:

A plane should not fly itself into the ground, switch flicked off or not.

Not sure I really understand this statement (I get the ideal but the statement isn't right). No plane "just flies" itself. That is why there are pilots (or in the future, pilot systems).

JohnKrist wrote:

dragon6172 wrote:

JohnKrist wrote:

Well, this plane wasn’t really unsupervised, was it?

Neither was AF447

Point being?

Pilot error can always defeat good design or exacerbate a design flaw.

And by the way, I am open to the fact that there could be a design issue that needs to be addressed/corrected

Tugg

XT6Wagon wrote:

anfromme wrote:

From there on, the main input by the crew was to pitch up, even though the stall warning was sounding all the way through.
.

No, the stall warning would shut off at high angles of attack. It would turn on as the nose dropped and the plane could measure airspeed again. So pulling up turned *OFF* the stall warning.

Sorry, this was from memory, on re-reading the details on the stall warning, I think we're both right and wrong.
Stall warning sounded for 54 seconds and ceded as the captain came back from the crew rest area. The warning then became intermittent, but certainly didn't cease altogether.
But you're right that as the AoA became simply too high, the stall warning shut off, and AF submitted a concern regarding that behaviour, as in that situation, the feedback to pilots may have been confusing: Pull up, stall warning stops (because of too-high AoA), push down (correct action against stall), stall warning starts again because AoA values would be within range again). Not sure whether any changes to the warning were implemented after that.

Anyway - my main point was that contrary to gensys's "drive itself into the ground" comparison of ET302/JT610 with AF447, AF447 wasn't a relevant example, as pretty much the exact opposite happened here. No more automatic systems and it was purely pilot input (which the plane adequately responded to throughout) that controlled the plane once the unreliable airspeed condition was detected by the flight control system.

DeltaMD90 wrote:

Way too much speculation going on from people without the proper expertise and hard facts from scene. Why can't we say "we don't know at this point??

osiris30 wrote:

As time has gone on I have continued to flesh out what *I* feel the chain of events is and to my mind now it starts before the take-off roll:

1) Either on prior flight or before commencing this flight; pilots of last flight or this flight disable MCAS as a precatuion (stab cut-off)
2) PIlots of this flight miss (or knew it was off), but fail to trim plane correctly.

What is your background? Are you in the airlines and/or a Boeing pilot? Granted I have not worked for the airlines, and I am not currently a MAX pilot (but I did fly 737-800s for a few years) and I have a VERY hard time believing what you are so sure or here

1: the previous pilots that supposedly got this malfunction and threw off the stab switches didn't relay this info to maintenance and/or maintenance didn't relay this info to the pilots/it wasn't seen in the write ups?

2: what do you mean "disable MCAS as a precaution?" As in they had flight control problems or uncommanded nose drops and switched the stab cutoff switches? That would make it even more unbelievable they simply forgot to tell maintenance/maintenance didn't immediately ground the plane/didn't tell this crew/this crew missed the write up? Or do you mean they disabled it "just in case"?

It's been a couple years since I flew the 737 but I'm 99.5% sure that would disable MCAS........ but also the pilots' electric trim and autopilot leaving you with only the obnoxious wheel. I have a hard time believing they would go through all that or if the airline's SOP would even allow that

3: then you say the mishap crew perhaps "missed" that the stab cutoff switches were off? Did they miss the write up that undoubtedly would have existed? Did they also just overlook these switches being set incorrectly in their cockpit flows/checklists? Did they also not set takeoff trim in the green band, something you also hit in the checklist before every flight or was it already coincidentally in the green band?

Or "they knew it was off," I'd be surprised if ET lets their pilots takeoff with these switches tripped or the pilots did it on their own accord, could be wrong but that does not sound right at all.

On top of all that, all that stuff that would draw their attention to trim, they fail to set it correctly? It's not some complex equation or something rarely done, you get the trim calculated out every single flight and it should fall in the green band


I'm not saying all that is impossible but it doesn't pass the sniff test. I'd say you should go back to the drawing board... but why? Why over speculate and come up with an answer? There are way too many unknowns, I as a former 737 pilot wouldn't feel comfortable speculating off the very little info we have, why can't we just say "we don't know" and wait for more info?

The speculation doesn't help much and makes us all talk in circles. The level of certainty you exhibited makes it even worse

But maybe I misunderstood your points or you have a lot more expertise in the area, maybe ET does things a lot differently than I'd imagine (if what you outlined is the case I'd say they're extremely incompetent)

1&2) disabled as a precaution. Not saying it happened but the plane sure looks mistrimmed based on the take off roll AND inability to climb.
3) Yes. I am suggesting that MAY have happened. Pilots have taken off in all kinds of incorrect configurations before. I am not saying this happened, but it wouldn't be without precident would it?

I am at a loss to explain take off performance unless the aircraft was out of trim. Given the airspeed the got up to on the data we have that thing should have been able to climb like a rocket.

Maybe its me but what has seemingly caused these accidents is hard to forgive from an engineering point of view.

In an industry which prides itself on excellence it is no where near the standard it should be.

When we treat planes like our home technology, fixing issues post production we have major major issues beginning. This isnt a minor issue, this is something that was so obvious that if there was a fault etc it could put the plane in danger that you have to ask how the hell did this not come up in risk assessment. And the cavalier attitude to "pilots should know what to do" is almost criminal. Yes they should but maybe something so critical in an early phase of a flight shouldn't have such a failure chance and clearly whatever they thought was ok was not.

It raises massive questions on where the industry is going. It was careless and a quick route on safety for profit and to get designs into the sky is not the way to go.

I hope their is a more thorough look into both Boeing and Airbus to make sure this isnt an unintended slippery slope. I love Boeing and Airbus and marvel at their planes but I do hope in this case there isnt negligence

kayik wrote:

...
It is not going to be like "we upgraded the software, let's fly". Certification will take ages. Given its credibility, FAA's decision is not enough, European authorities and Asians should be convinced, as well.
.

They have been working on software fix since Nov '18. Boeing Defense Systems has vast experience with software to control airframes lacking static stability. Most modern fighter planes are inherently unstable for various reasons. So it is not impossible with just software fix for Boeing. Just tighten the loose ends and make it more intuitive to human pilots.

I think any reasonable fix will be quickly accepted and frames should flying again very soon. No one wants (or) can afford to keep these grounded for a long time.

There will be a judgment call on the cost of major MAX redesign (vs) clean sheet design. If the redesign costs too much Boeing may roll out the new plane and let customers swap orders.

Wallhart wrote:

This isnt a minor issue, this is something that was so obvious that if there was a fault etc it could put the plane in danger that you have to ask how the hell did this not come up in risk assessment.

My point exactly - considering the characteristics of MCAS that Boeing is now fixing (limit trim it can exert, limit the number of MCAS trim cycles within a given time period, feed it data from more than one sensor) I am flabbergasted as to how this made it through the first solution design round, never mind through certification.
To me, this raises some questions about the quality of the certification process. Distrust in that process is much worse in my view than distrust in the department within Boeing that designed MCAS.

747megatop wrote:

It is as simple as Mercedes, BMW or Toyota putting in a feature where, it accelerates the car when you hit the brake pedal and people arguing that the driver did not have enough experience or should have flipped some switches to disconnect that feature!!!!

That's an interesting parallel you draw, because the final investigation into this issue found that it had nothing to do with the cars, the pedals, or the switches; people were stepping on the wrong pedal (they were hitting the gas instead of the brake). This is actually not a new phenomenon; it happened with Audis in the 1980s, was similarly investigated on technical grounds, and was ultimately revealed to be, yes, people stepping on the wrong pedal.

Malcolm Gladwell actually did a very interesting podcast on the issue, if you're interested. Revisionist History is the name of the podcast, episode called "Blame Game."

So, once again, we don't know what happened on this plane. But your analogy isn't very good evidence for your position. People are more likely to make mistakes than machines.

dtw2hyd wrote:

kayik wrote:

...
It is not going to be like "we upgraded the software, let's fly". Certification will take ages. Given its credibility, FAA's decision is not enough, European authorities and Asians should be convinced, as well.
.

They have been working on software fix since Nov '18. Boeing Defense Systems has vast experience with software to control airframes lacking static stability. Most modern fighter planes are inherently unstable for various reasons. So it is not impossible with just software fix for Boeing. Just tighten the loose ends and make it more intuitive to human pilots.

I think any reasonable fix will be quickly accepted and frames should flying again very soon. No one wants (or) can afford to keep these grounded for a long time.

There will be a judgment call on the cost of major MAX redesign (vs) clean sheet design. If the redesign costs too much Boeing may roll out the new plane and let customers swap orders.

Lets hope whatever they put in place makes sure we dont get another Max go down ever. Because if there is in the next couple of years, the plane will be finished and trust will have completely evaperated. It would hit Boeing even harder than this potentially does because confidence and trust is something you earn. If its lost its hard to get back at a competitive cost to business.

I updated my chart based on the FR24 data:

• Started plotting earlier at the begin of takeoff roll instead of when FR24 indicated "airborne". I am doubtful FR24's "airborne" is accurate since the ground speed was only 93 knots, and the plane was only 1900 ft from threshold, only 15% of the runway length. The runway does rise in the middle.
• Added some markers indicating the end of runway 07R. I am doubtful of the accuracy of the Pressure Altitude while the plane is still over the runway, so I would disregard the Pressure Altitude numbers while it is over the runway.
• Looked up Ground/Terrain Elevation for the GPS points and added that. At 153s, the AGL was only 225 ft! Shortly after that, they were able to gain significant altitude somehow.

Same as before:

• X-axis is elapsed seconds (not distance).
• Altitude/elevation is relative to the initial value (to give better resolution on the plot).

dtw2hyd wrote:

kayik wrote:

...
It is not going to be like "we upgraded the software, let's fly". Certification will take ages. Given its credibility, FAA's decision is not enough, European authorities and Asians should be convinced, as well.
.

They have been working on software fix since Nov '18. Boeing Defense Systems has vast experience with software to control airframes lacking static stability. Most modern fighter planes are inherently unstable for various reasons. So it is not impossible with just software fix for Boeing. Just tighten the loose ends and make it more intuitive to human pilots.

I think any reasonable fix will be quickly accepted and frames should flying again very soon. No one wants (or) can afford to keep these grounded for a long time.

There will be a judgment call on the cost of major MAX redesign (vs) clean sheet design. If the redesign costs too much Boeing may roll out the new plane and let customers swap orders.

From parts of the regulations that have been posted in these threads I understand that it is not permissible for a civil airliner to rely on software systems to make it stable in flight. If the 737 MAX relies on such systems to make it stay in the air at any phase of flight it shouldn't have been certificated. I am only going from what I think I have learned here in these threads; correct me if I am wrong.

Interflug74 wrote:

Why not putting an 200hrs pilot on an already safe Plane, that was made even safer?

The discussion of whether 200 hours are enough to fly a 737 full of pax really bothers me. Let's say you can fly 50 times in these 200 hours. About four or five of them really pose a challenge. In the those 45 other flights, the learning curve is quite flat. No tough decisions, no critical thinking, no real need for CRM... an effective training regimen provided by the airlines will make a much bigger change, than just flying experience itself.

As a sportsball referee, I can say that some of us can referee national games with just three years of experience. For others, it takes 15 years to reach that level. Some have played volleyball since they're 10 years old, but they're still worse referees than myself. The crucial thing is not the bare hours of experience, it's the seriousness with which you prepare and review each assignment.


David

osiris30 wrote:

1&2) disabled as a precaution. Not saying it happened but the plane sure looks mistrimmed based on the take off roll AND inability to climb.
3) Yes. I am suggesting that MAY have happened. Pilots have taken off in all kinds of incorrect configurations before. I am not saying this happened, but it wouldn't be without precident would it?

I am at a loss to explain take off performance unless the aircraft was out of trim. Given the airspeed the got up to on the data we have that thing should have been able to climb like a rocket.

Disabled as a precaution? By the airline? By the pilots? That sounds like a completely unrealistic solution. Again, you'd have a plane without autopilot and without electric trim. I'd be absolutely shocked if ET allowed this or the pilots thought that was a good idea. In fact, if ET went to such lengths, they probably wouldn't have even bothered to fly them in the first place and just grounded them right off the bat. This makes no sense

You seem to be connecting a lot of dots really early on. There may be 20 different things that happened, and that's assuming [u]we have no inaccurate information currently.[u]

And yes, pilots have taken off in incorrect configurations before. Trust me, a slightly untrimmed 737 isn't going go bonkers when you lift off. It may cause you to rotate a bit too fast or require more back stick pressure, but it's not like it would be completely uncontrollable. It gets harder and harder the further you get from the green band for takeoff... But what are you suggesting? In addition to not knowing about a gripe on a previous flight, and in addition to them overlooking these switches/wanting them off for some crazy reason, and in addition to them being out of the green band for takeoff, it was trimmed to full nose forward or back or something? Which again, that alone would be annoying and more difficult (but not impossible to control)

Think you're way off the mark here. A lot of stuff isn't making sense, let's just stick to what we know (and can confirm btw! Perhaps some of the FR24 info or something else is a bit off or faulty) and not connect dots for the sake of connecting dots




Further more I want everyone to just remember it's possible to fly these aircraft out of trim and even without hydraulics. While I never had that in real life (thankfully) I practiced it in the sim. I wouldn't be surprised if confusion or disorientation came into play and I don't know about the MAX (only the NG) but trim alone shouldn't be able to overpower the pilots (can fight or disorient though)

dtw2hyd wrote:

...Boeing Defense Systems has vast experience with software to control airframes lacking static stability. Most modern fighter planes are inherently unstable for various reasons. So it is not impossible with just software fix for Boeing. Just tighten the loose ends and make it more intuitive to human pilots...

I am sure they have, as they have experience in building commercial aircraft. What I am saying is, they will eventually fly the grounded aircraft but will they be able sell them anymore and keep their order book intact. We are talking about human passengers at the end.

Hmm.. You are flying at 2000ft with 400kts. Stick shaker on. Screens lit like a Christmas tree.
MCAS kicks in, plane starts to drop. Column too heavy to hold back with two hands.
Now you need to troubleshoot, make a decision to switch off the trim, take one hand off from the column, reach behind to switch the trim off, start manually rotating the trim while flying with one hand with a column too heavy to hold back.
Is this physically possible? How much time one would have for this before...Boom!
How fast does a plane drop 2000ft if it is flying at 400kts and you push it down?

Finn350 wrote:

CO953 wrote:

smartplane wrote:

It's a feature Boeing added to perpetuate grandfathering. It is a requirement for certification, in order to mimic, within approved tolerances, the flight behaviour of the NG.

The MAX, within approved tolerances mimics the NG. The NG, within tolerances mimics the Classic. The Classic, within approved tolerances, mimics the 100/200. But the ultimate parent is the 100/200, which after applying multiple layers of tolerances, bears little or no resemblance to the flight behaviour of the MAX, even with electronic cloaking to make it seem so.

What you're describing is the logical endpoint of a once-vibrant American (and global) aircraft-manufacturing industry which narrowed itself, at least in the Western world, to a duopoly and - in the USA - a monopoly. Monopolies create certain efficiencies but also certain dangers. The freight train of the MAX program carried a lot of momentum. It still does. Dang good chance that a flawed aircraft, which may actually not be fixable, still gets rammed down everyone's throats, instead of actually killing the program.

I have no animus to Boeing at all. Great company, with huge historical success and legendary contribution to aviation. Boeing may be the only company that can survive flat-out scrapping an aircraft type.

Before I get crowd-attacked, let me ask this:

Can the landing gear be made longer to accommodate moving the engines backward and eliminate the drag issue underlying this whole fiasco? I don't think so, due to width of the fuselage and the spacing of the engine pylons.

Can a telescoping landing gear be designed that would accommodate the width of the fuselage and the spacing of the engine pylons.... maaaaaaaaaaaaybe.

Can the airliner be made as safe as the NG in its current configuration, even with software fixes? ......... hmmmmm

Is this fair to the pilots and crew, not to mention the traveling public, as we get forced to fly the MAX for the next 25 years? .......hmmmmmmm

Does an entire globe-full of airlines keep up 5,000 orders for a plane that strongly appears to be a safety retrogression? In our current political state of "no rules" and disrespect for the rule of law .... ????????

This is a very ugly moment, for sure.

In the short term, there will be a simple software fix to address the specific MCAS design fault. In the long term, Boeing will replace the 737 with a new clean sheet design. They had been contemplating that already before this debacle, and this is the final push for earnestly starting design work for a clean sheet. There is no point to make additional changes to the 737 frame (it would be adding lipstick over lipstick as some members here call it). Irony here is that as a consequence of these mishaps, A320neo will get a potent rival from Boeing.

I understand your point.

But let me ask you... is it OK that Boeing releases 5,000 Kludgeliners onto the flying public, and we should all just grin and bear it until they all retire due to age, and accept a raised crash rate due to the engine placement?

I'm not happy with that outcome. In all honestly, I hope that killing the program is kept in the list of options, and that the final solution is chosen with safety paramount.

If Boeing can fix the MAX and make it as safe as the NG, great! If not, are we all OK in the aviation community with allowing a 21st-century safety backslide, for the life of the MAX, so as to prevent economic harm to the manufacturer?

Again, not targeting Boeing. I'm looking at the long-term. If they think they'll push out 5,000 more aircraft that my family is flying on, this thing had better be done by the effin' book. This is the risk that Boeing incurred by donning the mantle of American monopoly.

DeltaMD90 wrote:

osiris30 wrote:

1&2) disabled as a precaution. Not saying it happened but the plane sure looks mistrimmed based on the take off roll AND inability to climb.
3) Yes. I am suggesting that MAY have happened. Pilots have taken off in all kinds of incorrect configurations before. I am not saying this happened, but it wouldn't be without precident would it?

I am at a loss to explain take off performance unless the aircraft was out of trim. Given the airspeed the got up to on the data we have that thing should have been able to climb like a rocket.

Disabled as a precaution? By the airline? By the pilots? That sounds like a completely unrealistic solution. Again, you'd have a plane without autopilot and without electric trim. I'd be absolutely shocked if ET allowed this or the pilots thought that was a good idea. In fact, if ET went to such lengths, they probably wouldn't have even bothered to fly them in the first place and just grounded them right off the bat. This makes no sense

I was pretty clear in my initial post that I am proposing the trim cut off switches were thrown by either the last crew or this crew as a precaution. Who the hell said anything about disabling auto-pilot? Just auto-trim... Not sure where you are getting this from, did I misword something in my post that has lead you to suggest they turned off the entire AP system? I am merely suggesting someone hit stab cut-off. Before you say 'wow that would be so weird I have never heard of it', there was a report in the Nasa database of an AA flight crew doing EXACTLY that, for EXACTLY this reason. (edit: I may be getting the soources or airlines mixed, but it was reported in this thread already, just not going to search for it).

You seem to be connecting a lot of dots really early on. There may be 20 different things that happened, and that's assuming [u]we have no inaccurate information currently.[u]

Man if you are going after that line of think you have a LOT of posts to write here!!!!

And yes, pilots have taken off in incorrect configurations before. Trust me, a slightly untrimmed 737 isn't going go bonkers when you lift off. It may cause you to rotate a bit too fast or require more back stick pressure, but it's not like it would be completely uncontrollable. It gets harder and harder the further you get from the green band for takeoff... But what are you suggesting? In addition to not knowing about a gripe on a previous flight, and in addition to them overlooking these switches/wanting them off for some crazy reason, and in addition to them being out of the green band for takeoff, it was trimmed to full nose forward or back or something? Which again, that alone would be annoying and more difficult (but not impossible to control)

Think you're way off the mark here. A lot of stuff isn't making sense, let's just stick to what we know (and can confirm btw! Perhaps some of the FR24 info or something else is a bit off or faulty) and not connect dots for the sake of connecting dots

I stated VERY clearly that I was postulating based on available data, and don't believe I claimed any of it as 'fact' (beyond what is know as fact). If you have a better explanation for a lack of climb performance (on take off) than incorrect trim when airspeed is well above what is needed to climb, PLEASE share it.

Further more I want everyone to just remember it's possible to fly these aircraft out of trim and even without hydraulics. While I never had that in real life (thankfully) I practiced it in the sim. I wouldn't be surprised if confusion or disorientation came into play and I don't know about the MAX (only the NG) but trim alone shouldn't be able to overpower the pilots (can fight or disorient though)

I don't think anyone is suggesting otherwise. I certainly am not. I agree fully with your last part of the statement (hell I even agree with some of your cautions before that point), not sure why this bit of speculation is the one you chose to single out though where there are 50+ pages of largely speculation here. At least mine I tried to fit the observed paramaters to address the TAKE OFF and INITIAL CLIMB portion of the flight.

osiris30 wrote:

I was pretty clear in my initial post that I am proposing the trim cut off switches were thrown by either the last crew or this crew as a precaution. Who the hell said anything about disabling auto-pilot? Just auto-trim... Not sure where you are getting this from, did I misword something in my post that has lead you to suggest they turned off the entire AP system? I am merely suggesting someone hit stab cut-off. Before you say 'wow that would be so weird I have never heard of it', there was a report in the Nasa database of an AA flight crew doing EXACTLY that, for EXACTLY this reason. (edit: I may be getting the soources or airlines mixed, but it was reported in this thread already, just not going to search for it).

If you turn off electric trim, the autopilot wont work, at least not in the pitch axis.

speedking wrote:

Hmm.. You are flying at 2000ft with 400kts. Stick shaker on. Screens lit like a Christmas tree.
MCAS kicks in, plane starts to drop. Column too heavy to hold back with two hands.
Now you need to troubleshoot, make a decision to switch off the trim, take one hand off from the column, reach behind to switch the trim off, start manually rotating the trim while flying with one hand with a column too heavy to hold back.
Is this physically possible? How much time one would have for this before...Boom!
How fast does a plane drop 2000ft if it is flying at 400kts and you push it down?

Or you could use that handy electric trim switch that's right under your thumb on the control column you're pulling so hard on to return the aircraft to a normal trim state before you disable electric trim. As has been pointed out numerous times the pilot ALWAYS has authority over MCAS inputs using the control column electric trim switch.

flybucky wrote:

I updated my chart based on the FR24 data:
[list]
[*]Started plotting earlier at the begin of takeoff roll instead of when FR24 indicated "airborne". I am doubtful FR24's "airborne" is accurate since the ground speed was only 93 knots, and the plane was only 1900 ft from threshold, only 15% of the runway length. The runway does rise in the middle.

"Airborne" signal comes from nose gear, very well could just have nose gear extended just enough to create the signal. Doesn't necessarily have to be off the ground