Ethiopian 737 Max 8 crash and Fallout

[jb747]

This is the part I don’t like about the system. It moves differently to the current speed trim system in that when MCAS is activated it will trim a hell of a lot quicker than manual electric trim. The current speed trim system actually moves slower than the electric trim.

It’s why I think these guys might have turned the stab back on. An attempt to trim it to a position they could handle, and where they could then turn it off again.

 

[AviatorInsight]

Okay, so next question...was this recoverable? What should have the pilots done (with the very limited time and altitude they had)? Or were they doomed as soon as the sensors started giving the wrong readings?

The last little bit of the trim runaway checklist is:

“If trim continues......trim wheel grasp and hold”.

 

[jb747]

Pulling the yoke aft tilts the rear of the elevator up. As it is connected to the Stabiliser in front of it, there would be a moment tilting the Stabiliser up from the airflow forces on the elevator.

Whilst what you are describing is the way older control surfaces worked (look up trim tabs), I doubt that there would be a great deal of flexing against your desired motion in this system.

The pilots would have been trying to rotate the trim wheel which tilts the Stabiliser down. How much mechanical advantage is in the trim wheel?

Very little. But it isn’t trying to move the tail directly. The actual motion is done by a huge screw jack, as it is in all large aircraft.

So the trim wheel is slow, takes a lot of rotations to significantly change aircraft attitude, and when yoke is maximally pulled aft , and at high speed, there is likely not enough mechanical advantage to move the Stabiliser rapidly enough in an emergency - likely slower than usual.

I doubt that mechanical advantage is an issue here. The problem is that the MCAS has a very fast trimming rate available to it, that exceeds what the pilots are given. Once the applied nose down trim exceeds the ability of the elevators to command a 1G AoA, then you’re in serious, probably terminal, trouble.

 

[jb747]

The last little bit of the trim runaway checklist is:

“If trim continues......trim wheel grasp and hold”.

Which doesn’t help you at all if it already has too much nose down trim to be countered by the elevators. It’s a checklist designed by people who never actually expected to have to use it.

The whole concept of trim runaways has always been around the idea of a stuck trim switch on the yoke....not a mad bit of software with so much authority, and so little sense.

 

[AviatorInsight]

Which doesn’t help you at all if it already has too much nose down trim to be countered by the elevators. It’s a checklist designed by people who never actually expected to have to use it.

The whole concept of trim runaways has always been around the idea of a stuck trim switch on the yoke....not a mad bit of software with so much authority, and so little sense.

True, but if they're already (supposedly) turned off the power to the trim, and it still runs like it did, would you not try to stop it by any means necessary to continue running away? Put your foot on it if you need to. Manually moving the trim wheel by hand will also override any electric input, sure it's not as effective as electric and you need muscle to move it, but it could have slowed down the process?

The problem was, was that the flaps were up. When flaps are retracted electric trim moves slower than if the flaps are extended.

 

[flyer89]

The MAX was a somewhat desperate response to the A320 NEO

Also, from what I’ve read after American Airlines ordered 300 A320/21’s and said they’d also like to order a whole bunch of 737’s with a new engine Boeing clearly felt their hand had been forced. This came after Boeing publicly stated that they were committed to building an entirely new aircraft to replace the 737. I’d imagine real or imagined pressure from the likes of Southwest probably pushed them over the edge as well.

 

[Berlin]

Latest news it that MCAS isn’t the only problem. Apparently, Boeing has found a second issue with their software:

https://www.washingtonpost.com/worl...4f948cc0605_story.html?utm_term=.6659fffaf879

 

[Himeno]

Also, from what I’ve read after American Airlines ordered 300 A320/21’s and said they’d also like to order a whole bunch of 737’s with a new engine Boeing clearly felt their hand had been forced. This came after Boeing publicly stated that they were committed to building an entirely new aircraft to replace the 737. I’d imagine real or imagined pressure from the likes of Southwest probably pushed them over the edge as well.

AA wanted to order 460 narrow bodies in 2011 to replace the 757s, MD80s, 767-200s and older 737s. They wanted them all to be 737s, but couldn't get the amount of aircraft they wanted in the time frame they wanted. Airbus also couldn't make that amount of A320s for a single customer in the time they wanted. So AA split the order. 200 737s and 260 A320s including a number of NEOs.
Boeing saw a large Boeing only operator buying A320NEOs and went "...cough".

Boeing was thinking that airlines would keep buying the 737NG while they worked on the 797.

 

[jb747]

AA wanted to order 460 narrow bodies in 2011 to replace the 757s, MD80s, 767-200s and older 737s. They wanted them all to be 737s, but couldn't get the amount of aircraft they wanted in the time frame they wanted. Airbus also couldn't make that amount of A320s for a single customer in the time they wanted. So AA split the order. 200 737s and 260 A320s including a number of NEOs.
Boeing saw a large Boeing only operator buying A320NEOs and went "...cough".

So, they’re now in the situation of having an old, kludged, design, that should never have existed in the first place, and which the public are now finding out has major hidden flaws. If you were an airline looking to buy, especially if a large enough number to offset any Airbus training costs, then you’d have to be seriously considering your options. I expect Boeing will recover, but I also suspect that there will be more damage overseas than at home in the USA. The ‘If it ain’t Boeing, I ain’t going crowd’ might have to reconsider.

It’s a terrible pity, because if they’d kept going with the original plan, we’d probably be seeing a decent NEO competitor about now....and possibly one capable of putting Airbus onto the back foot.

The only positive for them is the fact that Airbus probably can’t gear up quickly enough to take complete advantage.

Boeing was thinking that airlines would keep buying the 737NG while they worked on the 797.

I guess they would have if it was priced at rock bottom.

 

[Daver6]

Are faulty AoA sensors (especially on new aircraft) that common?

 

[Mogul]

Are faulty AoA sensors (especially on new aircraft) that common?

In the 737 MAX's case the answer would be a definate yes.

 

[ermen]

The ‘If it ain’t Boeing, I ain’t going crowd’ might have to reconsider.

a little off topic - but its really a "if it ain't Airbus, I ain't going" at the moment.

dont understand why there is/was so much AIrbus hate? they make beautiful planes

A380 (beautiful whale)
A350 (my favourite plane at the moment as it is good for 3-3-3 in Y or 1-2-1 in J) versus 787 (smaller, and narrower)
A320 (don't see the plane as any worse than the 737?)

 

[Berlin]

a little off topic - but its really a "if it ain't Airbus, I ain't going" at the moment.

dont understand why there is/was so much AIrbus hate? they make beautiful planes

A380 (beautiful whale)
A350 (my favourite plane at the moment as it is good for 3-3-3 in Y or 1-2-1 in J) versus 787 (smaller, and narrower)
A320 (don't see the plane as any worse than the 737?)

Totally agree- beautiful planes.

Both my (German) dad and my (French, and employed by airbus) host family dad in Toulouse said in the early 90ies already:

“If it’s Boeing, I ain’t going”.

I think both versions are silly, to be honest.

 

[OATEK]

From what we have read so far, and the analysis of our AFF pilots, then this plane was not safe.

It makes the comments from Boeing about how they were making a safe plane even safer sound as hollow as many on here thought when first uttered. And their insistence that the runaway trim defense and turning the stab switches off was all that was needed, pointing to poor flying, is even worse.

Years ago when doing some postgrad study, one subject was on crisis management and the underlying theme was own the problem/issue. It seems to me that Boeing in not following this dictum condemned that second aircraft to crash, something that will (rightfully) hang around their necks for a long time to come.

 

[woodborer]

From what we have read so far, and the analysis of our AFF pilots, then this plane was not safe.

It makes the comments from Boeing about how they were making a safe plane even safer sound as hollow as many on here thought when first uttered. And their insistence that the runaway trim defense and turning the stab switches off was all that was needed, pointing to poor flying, is even worse.

Years ago when doing some postgrad study, one subject was on crisis management and the underlying theme was own the problem/issue. It seems to me that Boeing in not following this dictum condemned that second aircraft to crash, something that will (rightfully) hang around their necks for a long time to come.

Not just Boeing. Lots of people just dismissed the first crash as a LionAir training issue....

 

[jb747]

Are faulty AoA sensors (especially on new aircraft) that common?

Not at all. I’ve only ever seen one sensor fault (it was sideslip, but the same basic sensor), and that was a failure of its heating.

dont understand why there is/was so much AIrbus hate? they make beautiful planes

I expect the phrase originated in the USA, and they aren’t at all parochial. Whilst most people mouthing such comments have little aviation knowledge, many pilots expressed the same feelings. Pretty well always, they’d only flown Boeing. So, it’s all very much a Holden / Ford argument, in which the various protagonists have rarely, if ever, tried the other side. The biggest myth about the AB is that the computer limits the pilots from doing what they might need to do. Yes there are limits, but they are sufficiently remote that the chances of you ever hitting them, much less needing to exceed them, are negligible. The joysticks in the AB are somewhat polarising, and the fact that they are not physically interlinked in a design failure in itself.

Airbus certainly have items that make you wonder what they were thinking, but then so do Boeing. Having flown both types, neither offers a perfect coughpit, but overall, I like the AB take better.

 

[Daver6]

Not at all. I’ve only ever seen one sensor fault (it was sideslip, but the same basic sensor), and that was a failure of its heating.

So bad batch perhaps? Or just bad luck? How come this issue isn't getting much air time?

 

[JinbaIttai]

A pilot for a US airline told managers months before October’s Lion Air crash in Indonesia that he was uncomfortable with the level of training he had received before he was scheduled to fly the Boeing 737 Max for the first time. But when he asked for more training, he faced difficulties in getting it—and even a form of
reprimand.

The pilot Quartz spoke to has about two decades experience with his current airline, and additional experience beyond that. He was assigned a two-hour video tutorial, in line with the FAA’s recommendation for pilots certified to fly an earlier variant of the 737, to which the 737 Max is related.

“After completing it, over the next couple of days I got to thinking that, you know, they said it wasn’t a different airplane, it was just the same airplane with some differences,” he said. “But I went back over my notes, and I went back in the iPad and reviewed some of the information and I realized it was actually, it was the same airframe, but it had different instrumentation, some of the things were in different places, it sat on the ground differently, and it was just a different airplane.”

At least two communications sent around by the airline noted pilots would see some differences between what was shown in the iPad tutorial and the actual Max. He told his superiors he wasn’t comfortable flying the plane and requested simulator training.

“I was going to see the airplane for the first time 45 minutes before departure, and have 45 minutes to adjust to this new aircraft, after which I was going to have 189 people in the back that I was responsible for,” he said. “So I filed a report with the company that I’m not comfortable flying as a pilot in command of this.”

His simulator request was denied as the carrier didn’t have simulators for the Max—even now, few airlines have Max simulators ready for training. A request to fly with an instructor the first time was also denied initially. Eventually, after a 45-minute conversation with the head of the airline’s 737 training department, he said the airline agreed that he could fly with an instructor on his first Max flight, which was scheduled for July between two US west coast cities.

“When we arrived in Los Angeles there was no instructor and so I called the flight duty manager to ask where the instructor was and he said he’d call back,” said the pilot. A few minutes later his chief pilot called him to say that he was off the trip if he was unwilling to fly.

“I was punished not just from being taken off the trip and having the pay subtracted from me but by having a ‘missed trip’ put in my schedule, which is the same as same as not showing up for the trip,” he said. “I’ve never had a missed trip and I was shocked that even though I was sitting in the seat in the airplane when I was taken off the trip, that I was given a missed trip.”

What happened when one US pilot asked for more training before flying the 737 Max

And even now that it's obvious to the world that these planes behave very differently to other 737s, some airlines still peddle the "they have the same type certification" cough.

 

[ermen]

A pilot for a US airline told managers months before October’s Lion Air crash in Indonesia that he was uncomfortable with the level of training he had received before he was scheduled to fly the Boeing 737 Max for the first time. But when he asked for more training, he faced difficulties in getting it—and even a form of
reprimand.

The pilot Quartz spoke to has about two decades experience with his current airline, and additional experience beyond that. He was assigned a two-hour video tutorial, in line with the FAA’s recommendation for pilots certified to fly an earlier variant of the 737, to which the 737 Max is related.

“After completing it, over the next couple of days I got to thinking that, you know, they said it wasn’t a different airplane, it was just the same airplane with some differences,” he said. “But I went back over my notes, and I went back in the iPad and reviewed some of the information and I realized it was actually, it was the same airframe, but it had different instrumentation, some of the things were in different places, it sat on the ground differently, and it was just a different airplane.”

At least two communications sent around by the airline noted pilots would see some differences between what was shown in the iPad tutorial and the actual Max. He told his superiors he wasn’t comfortable flying the plane and requested simulator training.

“I was going to see the airplane for the first time 45 minutes before departure, and have 45 minutes to adjust to this new aircraft, after which I was going to have 189 people in the back that I was responsible for,” he said. “So I filed a report with the company that I’m not comfortable flying as a pilot in command of this.”

His simulator request was denied as the carrier didn’t have simulators for the Max—even now, few airlines have Max simulators ready for training. A request to fly with an instructor the first time was also denied initially. Eventually, after a 45-minute conversation with the head of the airline’s 737 training department, he said the airline agreed that he could fly with an instructor on his first Max flight, which was scheduled for July between two US west coast cities.

“When we arrived in Los Angeles there was no instructor and so I called the flight duty manager to ask where the instructor was and he said he’d call back,” said the pilot. A few minutes later his chief pilot called him to say that he was off the trip if he was unwilling to fly.

“I was punished not just from being taken off the trip and having the pay subtracted from me but by having a ‘missed trip’ put in my schedule, which is the same as same as not showing up for the trip,” he said. “I’ve never had a missed trip and I was shocked that even though I was sitting in the seat in the airplane when I was taken off the trip, that I was given a missed trip.”

What happened when one US pilot asked for more training before flying the 737 Max

And even now that it's obvious to the world that these planes behave very differently to other 737s, some airlines still peddle the "they have the same type certification" cough.

wonder which airline this is?
should boycott them.

what a farce with airlines pushing boeing to come up with this sort of cough without proper training, and the FAA complying

 

[p--and--t]

Seems the "fix" is progressing

Boeing conducts 737 MAX test flight with chief executive on board