smartplane
Posts: 1024
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Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 2:12 am

BravoOne wrote:
KlimaBXsst wrote:
So... NO MAX 737 sim time for the 29 year old pilot.

Which airlines in the US and Europe were allowing their pilots to fly the MAX 737 with NO MAX sim time?

Sorry if it’s been mentioned already but this thread is now quite long.



Don't think SWA has an approved MAX sim yet, nor for that matter UAL or AA? As a matter of fact, I don't believe the original design specs for the sims include the ability to emulate a MCAS failure as it was never meant to be a player. I'm confident the the first batch of sims built for Boeing do not replicate this feature.

Based on comments earlier in this thread, probably the biggest difference in NG v MAX simulators until now, is the MAX logo. Has the media got it's hands on a MAX simulator yet to test out any theories?
 
CO953
Posts: 515
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Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 2:13 am

Backseater wrote:
jollo wrote:
PixelFlight wrote:

Yes, this is possible using predictor and filters. In this case the predictor will model the flight dynamic from all available inputs (energy state, control surfaces position, inertial reference, GPS, sensors, etc..) and the filters will be a probability function that represent how much the input fit the prediction. A such system can even predict usable AoA value (with less probability) even in case of all AoA sensors give erratic values. I don't know why the civil aircraft industry don't use it. It's old tech that started with Kalman filter on Apollo missions. New predictors and filters are far more powerful and more accurate. The robotic industry use then routinely.


My points stands: a fail-safe design needs at least 3 inputs. You're proposing to replace a straightforward 3-sensor data vetting logic (which can nevertheless have it's intricacies: the devil is in the details, ask Airbus about Quantas Flight 72) with an estimator using all other available inputs (whose quality is not a given): good luck certifying that. Besides, I sincerely doubt the FCC has the juice to run your predictor in real time (unless you want to put a new box in the avionics bay, perhaps with a few custom ASICs inside? Again, good luck "grandfathering" your NG certification).

And where do you plan to install your 3 sensors to ensure that at least 2 are in agreement?
Or are you going to install 4, a pair on each side of the airplane?


I'll bite. I vote for 7 sensors, if the parts are made nowadays, approved by modern regulators. I'm sick of hurting myself using Harbor Freight Tools junk. I bought a pair of 6-Ton jackstands last month, which collapsed with hand pressure right out of the box, just as I was about to lift up a 6,000-lb car and place it upon said stands and get underneath the car. The casting was a joke. Looked like 6-year-old kids made it out of Plaster of Paris.

Junk sensors = crashed aircraft.
 
AviationBob
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Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 3:08 am

rheinwaldner wrote:
AviationBob wrote:
..., but the question of crew response has to be scrutinized too, especially when it seems they should have known/done this step by memory without any consultation of a manual.

Boeings checklist does not cover this case. The symptoms are different.

If the pilot is very attentive when flying manually, he will immediately counter the MCAS nose down moment, hence the upward correction, which needs to be applied is small too.

There was only a slightly increased force on the control column to keep the nose up (which impossibly cant be recognized as a runaway), countered by an unsuspicious and small trim up input. Completely different symptoms to a stab runaway.

737 pilots are also reporting, that sim training of the stab runaway NNC was done rarely and if it was done, the issue occurred isolated and as a continuous runaway. It was easy to detect as stab runaway in sim. Not so during these two crashes, as we have strong evidence.

What is the evidence?
Despite the overwhelming number of bad pilots flying badly maintained 737 NGs, the crash rate is so much better than the MAX's, that you impossibly can blame anything else than primarily the MAX.

The MAX is the common denominator. Not the bad pilots. Bad pilots do well with other aircraft.

In fact, bad pilots handle amazingly well basically any other jet aircraft beside the MAX.


Hence, why it's so important to have "Good" Pilots who are well trained and experienced enough to figure out that if you have what appears to be a runaway stabilizer, that maybe you should give the cut-out switches a try.
 
PixelPilot
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Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 3:37 am

washingtonflyer wrote:
Article now appearing in the Washington Post throwing a little shade on Ethiopian's perceived stellar safety record.

https://www.washingtonpost.com/business ... ords-show/


I would say that's not shade as you say it but facts that initially a lot of people dismissed because hey lets hate on boeing.
Give it time. Things will balance.
 
patplan
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Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 3:38 am

PW100 wrote:
AviationBob wrote:
mrbots wrote:
...snipped...
I suspect that the accident crews were very concerned about, and focused on unreliable air speed, stall warnings, stick shaker going off, and possibly many more alarms and alerts. To the point that they experienced that one of these was their main and major issue, and simply did not experience the trim as an issue (let alone the thing that would eventually kill them).

It could also be that they thought that turning off electric trim altogether, might even make their task more difficult, as they would then have been relegated to hand turning the wheel to control the airplane and its nose down tendency. Electric trimming is much easier than hand trimming, especially if you need most of your physical strength just to keep the control column all the way back.

They probably had a lot of things going on at the same time. They knew the electric trimming worked and they were successful in using it to their advantage to control the airplane. Shutting it of might have deprived them (in their mind) from one thing they knew did work for them, never realizing that at the same time it was the very thing working against them.

In the JT crash, did the trimming issue kick in at the same time as the stall warning, unreliable airspeed and AoA issues, or did that occur only later when MCAS became active? If so, then could that be another part of the explanation why trimming issue was not perceived nor recognized as the thing that could/would be the fatal issue.


To partially answer your question, here's the partial graph found on page 14 of the NTSC's Preliminary Report of its investigation:

Image

Yes, stick shaker had showed up way before MCAS is activated...Although there are more than a couple of blips of MCAS activation when the flap is on?? Curious.
 
Backseater
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Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 3:42 am

CO953 wrote:
Backseater wrote:
jollo wrote:

My points stands: a fail-safe design needs at least 3 inputs. You're proposing to replace a straightforward 3-sensor data vetting logic (which can nevertheless have it's intricacies: the devil is in the details, ask Airbus about Quantas Flight 72) with an estimator using all other available inputs (whose quality is not a given): good luck certifying that. Besides, I sincerely doubt the FCC has the juice to run your predictor in real time (unless you want to put a new box in the avionics bay, perhaps with a few custom ASICs inside? Again, good luck "grandfathering" your NG certification).

And where do you plan to install your 3 sensors to ensure that at least 2 are in agreement?
Or are you going to install 4, a pair on each side of the airplane?


I'll bite. I vote for 7 sensors, if the parts are made nowadays, approved by modern regulators. I'm sick of hurting myself using Harbor Freight Tools junk. I bought a pair of 6-Ton jackstands last month, which collapsed with hand pressure right out of the box, just as I was about to lift up a 6,000-lb car and place it upon said stands and get underneath the car. The casting was a joke. Looked like 6-year-old kids made it out of Plaster of Paris.

Junk sensors = crashed aircraft.

My point was not to be facetious. I believe that AoA measurements are tricky. They fluctuate and are a/c location dependent. Particularly during (M)aneuvers. That’s “M” for MCAS!
 
PStechPaul
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Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 4:48 am

I've been following most of this thread and the last few pages of the Lion Air thread, with great interest. So I decided to join in order to reply, but I had problems registering and logging on. Now that seems to be resolved but I can't submit an Avatar or other profile data, and the "contact us" form doesn't work. So hopefully an admin can fix that.

I have learned a lot about the monitoring and control systems for passenger jets from these discussions, and as a long time electronics design engineer I understand some of the pressures and overriding decisions that can be imposed by management in opposition to what I consider proper engineering practices. But fortunately the products I have designed and modified do not present such disastrous consequences of failure, as do systems in public transportation, particular airliners, but also as have had deadly consequences in railroad incidents.

At this point I would definitely avoid flying in a Boeing 373MAX, and I'd prefer not even flying at all unless absolutely necessary. But the publicity of these two recent aircraft tragedies will certainly result in hightened awareness and better safety systems and training, although it might take some time.

Although perhaps a subject for another thread, I would like to discuss the relative safety and efficiency of prop-driven aircraft versus jets. I understand that for longer flights over 500-1000 miles or so, jets are much more efficient, especially considering fuel consumption per passenger-mile, as well as reduced time. But I think I'd be willing to take a bit longer to travel in an aircraft that can remain airborne and able to be controlled and land at much lower speeds and shorter runways. I understand the competition and business decisions based on profits and market share, but they may also result in critical safety issues.
 
osiris30
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Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 5:26 am

patplan wrote:
PW100 wrote:
AviationBob wrote:


To partially answer your question, here's the partial graph found on page 14 of the NTSC's Preliminary Report of its investigation:

Image

Yes, stick shaker had showed up way before MCAS is activated...Although there are more than a couple of blips of MCAS activation when the flap is on?? Curious.


You are misreading the graph. That is a shared line for STS and MCAS. Both are in yellow. The blips are STS.
I don't care what you think of my opinion. It's my opinion, so have a nice day :)
 
ikramerica
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Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 6:08 am

PixelPilot wrote:
washingtonflyer wrote:
Article now appearing in the Washington Post throwing a little shade on Ethiopian's perceived stellar safety record.

https://www.washingtonpost.com/business ... ords-show/


I would say that's not shade as you say it but facts that initially a lot of people dismissed because hey lets hate on boeing.
Give it time. Things will balance.

I had suggested that early on, not as a disparaging of ET, just as a fact, that “fast growing” companies have difficulty maintaining quality and standards. Often the reality outpaces reputation, so the public doesnt realize what is happening behind the scenes until well after the problems begin. .
Of all the things to worry about... the Wookie has no pants.
 
Interested
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Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 6:24 am

PixelPilot wrote:
washingtonflyer wrote:
Article now appearing in the Washington Post throwing a little shade on Ethiopian's perceived stellar safety record.

https://www.washingtonpost.com/business ... ords-show/


I would say that's not shade as you say it but facts that initially a lot of people dismissed because hey lets hate on boeing.
Give it time. Things will balance.


Actuaally as this story has developed its just got worse and worse for Boeing

As it stands only about. 1 per cent of the general public know that the new system that crashed two planes and killed 300 plus people was hidden by Boeing

And as it stands only 1 per cent of the general public know about any training being done on an iPad etc

Once the films and documentaries get made in the next couple of years - this will prove to be one of Boeing's darkest hours

There will be resignations, sackings and worst case prison sentences

Your wish to blame pilots in some way for not dealing with the issues caused by the inherent plane faults and lack of training etc will be so secondary to the bigger story
 
Interested
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Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 6:27 am

ikramerica wrote:
PixelPilot wrote:
washingtonflyer wrote:
Article now appearing in the Washington Post throwing a little shade on Ethiopian's perceived stellar safety record.

https://www.washingtonpost.com/business ... ords-show/


I would say that's not shade as you say it but facts that initially a lot of people dismissed because hey lets hate on boeing.
Give it time. Things will balance.

I had suggested that early on, not as a disparaging of ET, just as a fact, that “fast growing” companies have difficulty maintaining quality and standards. Often the reality outpaces reputation, so the public doesnt realize what is happening behind the scenes until well after the problems begin. .


I assume that growing company you describe where people don't realise what is happening behind the scenes is Boeing?

After all they are the ones subject to FBI investigation right now (amongst others investigations?)
Last edited by Interested on Fri Mar 22, 2019 6:50 am, edited 1 time in total.
 
rheinwaldner
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Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 7:14 am

Buffalomatt1027 wrote:
While Boeing and the MAX have some issues to solve ...... the common denominator is also bad / poor training for the MAX.

Boeing said the MAX does basically not need any other training than the NG. So if the bad / poor training would be a factor, NGs should be crashing due to it too. In masses. Therefore bad / poor training ist not the common denominator. The common denominator is the MAX.
Many things are difficult, all things are possible!
 
Interested
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Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 7:18 am

PixelPilot wrote:
washingtonflyer wrote:
Article now appearing in the Washington Post throwing a little shade on Ethiopian's perceived stellar safety record.

https://www.washingtonpost.com/business ... ords-show/


I would say that's not shade as you say it but facts that initially a lot of people dismissed because hey lets hate on boeing.
Give it time. Things will balance.


An Indonesian airline cancelled an order for 49 x Max 737s yesterday. According to the article I read the order was worth 4.9 Billion Dollars

And you believe give it time and things will balance?

It's a domino effect. Every headline about these planes is a bad news story

Google "737 Max” and look at the headlines - it's bad news story after bad news story. Whatever fault gets apportioned to pilots is only going to be a small mention in any of this. Whatever fault is found against a pilot or pilots (if any) its going to be prefaced by the fact that MCAS wasn't trained or even mentioned to them. That's where the scandal is I'm afraid. And it is scandalous.

Here's just 5 random news headlines from across the world in last 24 hours when you Google " 737 Max”

"Breaking: Garuda Indonesia Cancels 49 Boeing 737 MAX Orders"

"Boeing sold essential safety features as extras on 737 Max"

"Pilots transitioned to 737 Max 8 with self-administered online course"

"Doomed Boeing planes lacked two optional safety features – report"

"FBI joins crnewinal probe into Boeing 737 Max 8 safety certification in wake of crashes"

That's just 5 from many more - all repeated internationally many times over in the last 24 hours.

Tomorrow there will be the same again. It's been like this for 2 or 3 weeks now.

If you work for Boeing in PR - where do you even start right now?

You are fighting a battle that is already lost Pixel. There's no magic cure to balance this out I'm afraid. You are dreaming if you believe that.

And worrying about what people think on here on this forum is minor compared to the damage that Boeing have done to their reputation in the real world

Keep saying "pilots" enough times won't make these storys disappear I'm afraid Pixel.
 
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speedbored
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Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 7:35 am

osiris30 wrote:
patplan wrote:
PW100 wrote:


To partially answer your question, here's the partial graph found on page 14 of the NTSC's Preliminary Report of its investigation:

Image

Yes, stick shaker had showed up way before MCAS is activated...Although there are more than a couple of blips of MCAS activation when the flap is on?? Curious.


You are misreading the graph. That is a shared line for STS and MCAS. Both are in yellow. The blips are STS.

To be fair, there's no way to differentiate between STS and MCAS adjustments on that graph.
Last edited by speedbored on Fri Mar 22, 2019 7:47 am, edited 2 times in total.
 
Paolo18
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Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 7:36 am

XRAYretired wrote:
Paolo18 wrote:
Why couldn't the mcas be fully turned off?



It would seem MCAS was always intended to be hidden in the background. It can only be isolated by turning off electric trim. An 'MCAS ON/OFF' switch in the cockpit would have been rather a giveaway. With a competant system design/limited authority for MCAS, this may well have worked.

Ray



It's simple isn't it?

A switch could have saved lives yet Boeing chose to override the pilot's input.

I quote Einstein, "the Universe may be finite, but human stupidity is infinite"
Last edited by Paolo18 on Fri Mar 22, 2019 7:38 am, edited 1 time in total.
 
Interested
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Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 7:38 am

A question that is going to actually become very relevant is:

If other airlines start following suit (which must be likely) and cancel their orders for 737 Max does it actually not solve a HUGE problem for the industry long term?

With all the bad news - A very possible scenario is nobody wants the plane now they know more about it - so lets not fix or certify something that nobody wants to buy into anymore

Basically we are just left with 350 existing planes to worry about. Can the industry handle that?

Cut the losses now

Clearly would be catastrophic financially short term for Boeing but at least we can move forward at some stage. Boeing or some form of Boeing will survive at least and learn from the whole sorry episode

Whilst Boeing create a new plane that is safe can they not focus on their other versions that are proven to be safe. Including the old 737 if needed
 
Menelaos
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Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 8:06 am

wjcandee wrote:
mjoelnir wrote:
wjcandee wrote:
Sorry. No it doesn't.


The NTSB would have skin in the game. An agency of the country that produced the frame. Protecting USA reputation, the FAA and Boeing.

That does not mean that I would distrust the NTSB. But an agency is not better or more reliable because it is from the USA. One could rather say that the FAA losing the golden shine reflects on other USA agencies.


Sorry. It doesn't work that way. They're an independent agency, and they criticize manufacturers, the FAA, and anybody else they think is standing in the way of safety. It's an awfully cynical and really sad view that you are expressing. What you're saying, however, is absolutely the case for Ethiopia. The two are vastly different. That's just the way it is.


Except it does work that way. In an ideal world, yes, independent agencies are 100% unaffected by the countries they're in. And yes, I fully agree that the NTSB has proven its quality many a time. However, there's an element of outside pressure that DOES have a material impact. Would the NTSB cave? Hopefully not, and they've shown in the past that they do a good job at that.

My problem with your original statement, however, is that you assume Ethiopia (the airline, the ministry, agencies) would have, as a default, zero ethics in their dealing with this situation because they have skin in the game. From that side, both countries have skin in the game, and pressure exists on both sides. Discrediting Ethiopian authorities and investigators like this implies they bring zero ethics to the table (contrary to the NTSB which by default is on a pedestal of independence and ethics), which is completely unacceptable from where I stand.
 
ltbewr
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Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 8:17 am

I suspect that with all the bad publicity it will take much longer, months beyond April, to figure out and properly 'fix' the 737MAX problem. There will be massive pressure on Boeing and the FAA by airlines to get the fixes done and get their grounded aircraft moving again but that cannot override the need to make the proper fixes and not create other problems. It will take a lot of engineering, testing on systems that should have been done in the first place, training of all pilots including on simulators that are set up for 737MAX use, as well as reassuring the public. We have seen other model aircraft, including earlier versions of the 737 as well as the MD-11, have significant design issues but with proper engineering fixes and training of pilots, still in use,

While 99.9999% of 737MAX flights seemed to have no problems, a relative tiny few did and within them, 2 fully deadly crashes. I do think Boeing will survive this in the long run but it has cost them in reputation. Beyond the fixes, Boeing needs to make managerial and cultural changes, even consider terminating the 737MAX model, return to the NG and work on a 'clean sheet' replacement to satisfy the public in the long run. We also need to end the politics so can properly staff and fund the USA's FAA to allow it to do its job, one it has done for decades and made flying far safer for all.
 
wjcandee
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Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 8:21 am

Dude, the reason that I'm skeptical of the Ethiopian authorities is that they were dishonest before, not because they're in Africa. And with an investigation with worldwide implications in the balance, they dick around for days about where to send the recorders, lock down any information getting out about them, then come out with zero factual information and just a bunch of conclusory statements about "similarities". Not an auspicious start.

So, to conclude: I am suspicious because of their past conduct in a similar situation, compounded by their current conduct. Allowing NTSB or BEA or AAIB, or all three, to have a hand in the investigation and an independent ability to report would do a lot to reestablish their credibility. The Libyans didn't have the organic skills to investigate the accident at Beirut at the highest level, so they brought in the BEA to work with their guys and help determine the questions to ask and the methodologies to follow and the information in the report. A great example of teamwork that produced a report that you can take to the bank. Here, not so much.
 
Paolo18
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Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 8:25 am

And so it begins....

Garuda Indonesia is seeking to scrap its multi-billion dollar order for 49 Boeing 737 Max 8 jets after the plane was involved in two fatal crashes.


https://www.bbc.com/news/business-47662967
 
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scbriml
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Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 8:28 am

PixelPilot wrote:
washingtonflyer wrote:
Article now appearing in the Washington Post throwing a little shade on Ethiopian's perceived stellar safety record.

https://www.washingtonpost.com/business ... ords-show/


I would say that's not shade as you say it but facts that initially a lot of people dismissed because hey lets hate on boeing.
Give it time. Things will balance.


More casual racism in the article.

The last para finishes:
"We don’t know how many other pilots may share these feelings … however when you look at these against the potential training problems with the 737 Max, training that the FAA said could be done through an iPad course, and the lack of 737 Max simulators, these don’t paint a very rosy picture of how Ethiopian Airlines views safety,” he said.

The issues listed there apply to just about every airline flying 737MAX in the World.
Time flies like an arrow. Fruit flies like a banana!
There are 10 types of people in the World - those that understand binary and those that don't.
 
dare100em
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Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 8:38 am

Bjorn has an article on LH which I foun very enlithening at least:

https://leehamnews.com/2019/03/22/bjorn ... sh-part-2/
 
jollo
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Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 8:44 am

Backseater wrote:
[
And where do you plan to install your 3 sensors to ensure that at least 2 are in agreement?
Or are you going to install 4, a pair on each side of the airplane?


The point of 3 sensors is not to have them all agree (even 2 AOA sensors on each side of the cockpit will most certainly "disagree", as in read different values at a given point in time, e.g. in a turrn). The point is to correctly identify and outvote a malfunctioning sensor. I'm no aerodynamicist, I wouldn't presume to know where to place a 3rd AOA sensor on a 737. IIRC on A320s the stand-by AOA sensor is aft.

Besides, I agree with you that AOA measurements are tricky. And if we were discussing a new clean-sheet design (with FBW controls from the outset) I would give serious consideration to the suggestion by member PixelFlight, a couple of pages back in this thread, to (also) include predictors in the control logic instead of just using sensor redundancy out of the 70s.

But here we're talking about the MAX, whose whole point is to be so much "just like an NG" not only to enjoy a grandfathered certification, but to also require no difference training for pilots: sorry, you don't get a multiple-digit fuel economy advantage just through minor tweaks, and you don't get to hide the - obvious - differences with poorly designed "control augmentation" devices, which are piggy-backed on top of existing systems without proper integration (and without even proper documentation, it would seem).

All accidents happen through multiple "holes" alignign themselves in most unfortunate ways: it looks to me that in this case, many of the holes shine right back to the concept and inception of the MAX.
 
RickNRoll
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Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 8:55 am

Interested wrote:
A question that is going to actually become very relevant is:

If other airlines start following suit (which must be likely) and cancel their orders for 737 Max does it actually not solve a HUGE problem for the industry long term?

With all the bad news - A very possible scenario is nobody wants the plane now they know more about it - so lets not fix or certify something that nobody wants to buy into anymore

Basically we are just left with 350 existing planes to worry about. Can the industry handle that?

Cut the losses now

Clearly would be catastrophic financially short term for Boeing but at least we can move forward at some stage. Boeing or some form of Boeing will survive at least and learn from the whole sorry episode

Whilst Boeing create a new plane that is safe can they not focus on their other versions that are proven to be safe. Including the old 737 if needed
Boeing is going to deliver thousands of MAX planes to customers and few customers will cancel their orders. It will, however, have this scandal tainting it's reputation for many years.
 
flybucky
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Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 9:06 am

Backseater wrote:
And where do you plan to install your 3 sensors to ensure that at least 2 are in agreement? Or are you going to install 4, a pair on each side of the airplane?


Perhaps the same place that the A320 installs their 3 AOA sensors?
 
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journeyperson
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Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 9:16 am

dare100em wrote:
Bjorn has an article on LH which I foun very enlithening at least:

https://leehamnews.com/2019/03/22/bjorn ... sh-part-2/


"Blowback". Just when you thought it couldn't get any more complicated!
 
jollo
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Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 9:26 am

wjcandee wrote:
Dude, the reason that I'm skeptical of the Ethiopian authorities is that they were dishonest before...


Care to share what specific episode(s) you are referring to? ET flight 409 (2010) was investigated by BEA and, as you say, you can take the final report "to the bank", ET flight 961 (1996) was hijacked, ET flight 604 (1988) was bird ingestion... when did ET dishonestly try to hijack and divert an investigation?
 
Paolo18
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Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 9:39 am

Boeing is not going to have a good 2019.

Boeing’s grounded airliners are likely to be parked longer now that European and Canadian regulators plan to conduct their own reviews of changes the company is making after two of the jets crashed.

The Europeans and Canadians want to do more than simply take the U.S. Federal Aviation Administration’s word that alterations to a key flight-control system will make the 737 Max safer.


https://www.voanews.com/a/european-cana ... 40725.html
 
glideslope900
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Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 9:49 am

scbriml wrote:
PixelPilot wrote:
washingtonflyer wrote:
Article now appearing in the Washington Post throwing a little shade on Ethiopian's perceived stellar safety record.

https://www.washingtonpost.com/business ... ords-show/


I would say that's not shade as you say it but facts that initially a lot of people dismissed because hey lets hate on boeing.
Give it time. Things will balance.


More casual racism in the article.

The last para finishes:
"We don’t know how many other pilots may share these feelings … however when you look at these against the potential training problems with the 737 Max, training that the FAA said could be done through an iPad course, and the lack of 737 Max simulators, these don’t paint a very rosy picture of how Ethiopian Airlines views safety,” he said.

The issues listed there apply to just about every airline flying 737MAX in the World.


Except no other airline in the world crashed a 737MAX (except Indonesia). Why does everyone immediately resort to crying “racism” over any critisizm of a non-western country?
 
XRAYretired
Posts: 632
Joined: Fri Mar 15, 2019 11:21 am

Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 9:57 am

journeyperson wrote:
dare100em wrote:
Bjorn has an article on LH which I foun very enlithening at least:

https://leehamnews.com/2019/03/22/bjorn ... sh-part-2/


"Blowback". Just when you thought it couldn't get any more complicated!
.

Hmm. The article is talking elevator blowback. Would assume elevators are rod actuated, so would also suspect this is possible for the elevators. Can anyone confirm this and what sort of airspeed and AOA this would occur? However, the article does not refer to stabilisers. Would assume stabilisers are ball-screw actuated? and anyway we know they were trimmed nose down (FDR for ET610, Inspection for ET302).

So I would guess its not a significant factor except maybe preventing recovery using the yoke alone.


Ray
 
User avatar
scbriml
Posts: 17485
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Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 10:06 am

glideslope900 wrote:
Why does everyone immediately resort to crying “racism” over any critisizm of a non-western country?


Because the casual racism is in that article exactly the same as it is in the Lion and Ethiopian threads. If you can't see it, you're not looking very well.

Compare the tone of the Atlas thread to those relating to the Lion and Ethiopian crashes. It would be completely different if it had been an Ethiopian crew that had flown a perfectly serviceable 767 into the ground.
Time flies like an arrow. Fruit flies like a banana!
There are 10 types of people in the World - those that understand binary and those that don't.
 
PlaneInsomniac
Posts: 418
Joined: Tue Nov 20, 2007 7:34 am

Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 10:09 am

AviationBob wrote:
[Hence, why it's so important to have "Good" Pilots who are well trained and experienced enough to figure out that if you have what appears to be a runaway stabilizer, that maybe you should give the cut-out switches a try.


Seriously, this again?

Problem is, it wasn't a "runaway stabilizer".

It was an unanticipated, intermittent failure mode of a faultily designed, undocumented and not properly certified system. MCAS, which had never been properly explained to them, changed the trim in bursts unpredictable for the pilots, in a stressful situation amidst other (aural) warnings and malfunctions.

Even "good" pilots likely wouldn't have been able to identify and remedy this unexplained behaviour from an undocumented system among various other malfunctions in the brief moments (in one case less than a minute IIRC) between when trouble started and the subsequent crash.

Particulary scary is the statement in https://leehamnews.com/2019/03/22/bjorn ... sh-part-2/ concerning the JT crash: Absent any help from the handbook, the crew was actively working to counteract the seemingly random trim changes, and had actually discussed the issue. However, "The FO trimmed, but he did it in too short periods". None of this could have been understood or solved even by a "good" crew.

The truth is, the MAX has been flying safely elsewhere because many other airlines paid additional money for further sensor malfunction indicators, which Boeing - it now seems: criminally - sold as optional extras for their buggy, semi-secret and self-certified MCAS.

Face it: This one is 100% Boeing's fault, even if some hypothetical perfect pilot may have had a miniscule chance of saving the day.

One.
Hundred.
Percent.
Am I cured? Slept 5 hours on last long-haul flight...
 
slowrambler
Posts: 139
Joined: Sat Nov 09, 2013 11:07 pm

Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 10:17 am

glideslope900 wrote:
Except no other airline in the world crashed a 737MAX (except Indonesia). Why does everyone immediately resort to crying “racism” over any critisizm of a non-western country?


ET hasn't trained all their pilots in a MAX simulator: terrible safety culture!
WN hasn't trained any of their pilots in a MAX simulator: shrug, what can one do really
 
XRAYretired
Posts: 632
Joined: Fri Mar 15, 2019 11:21 am

Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 10:53 am

glideslope900 wrote:
scbriml wrote:
PixelPilot wrote:

I would say that's not shade as you say it but facts that initially a lot of people dismissed because hey lets hate on boeing.
Give it time. Things will balance.


More casual racism in the article.

The last para finishes:
"We don’t know how many other pilots may share these feelings … however when you look at these against the potential training problems with the 737 Max, training that the FAA said could be done through an iPad course, and the lack of 737 Max simulators, these don’t paint a very rosy picture of how Ethiopian Airlines views safety,” he said.

The issues listed there apply to just about every airline flying 737MAX in the World.


Except no other airline in the world crashed a 737MAX (except Indonesia). Why does everyone immediately resort to crying “racism” over any critisizm of a non-western country?


The PIC of the Indonesian aircraft was an Indian and the PIC of the Ethiopian aircraft was an Indonesian.The Plot thickens!
 
OlafW
Posts: 304
Joined: Sat Jul 11, 2009 6:15 pm

Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 11:27 am

Another question as I don't know too much about flight physics and systems: How would the AoA sensor behave during a turn? I seem to remember that flying a curve usually correlates with changing altitude, but I'm not sure about that.
And what would happen if you move the stabilizer during a turn? Is that something a pilot would normally do?
Leading up to my main question: MCAS can be somewhat counteracted during straight flight, as it seems. But what if the MCAS-induced stabilizer trim kicks in during a turn? I get the impression that both the Lion and the Ethiopian flights were in the process of turning back when they crashed. Could a stabilizer movement during a turn leave the aircraft completely uncontrollable?
 
XRAYretired
Posts: 632
Joined: Fri Mar 15, 2019 11:21 am

Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 11:28 am

:| They crashed one of the planes boss. Pilots are dead.
:twisted: Execute the pilots!
:| OK. Preventative Action?
:twisted: Make sure the other pilots know they will be executed as well if they die crashing one of the planes!
 
User avatar
SheikhDjibouti
Posts: 1773
Joined: Sat Sep 30, 2017 4:59 pm

Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 11:47 am

OlafW wrote:
Another question as I don't know too much about flight physics and systems: How would the AoA sensor behave during a turn? I seem to remember that flying a curve usually correlates with changing altitude, but I'm not sure about that.
And what would happen if you move the stabilizer during a turn? Is that something a pilot would normally do?
Leading up to my main question: MCAS can be somewhat counteracted during straight flight, as it seems. But what if the MCAS-induced stabilizer trim kicks in during a turn? I get the impression that both the Lion and the Ethiopian flights were in the process of turning back when they crashed. Could a stabilizer movement during a turn leave the aircraft completely uncontrollable?

I've posted this before.
Boeing MOM -18-0664-01B dated 11 Nov 2018
The MCAS functions commands nose down stabilizer to enhance pitch characteristics during steep turns with elevated load factors and during flaps up flight at airspeeds approaching stall

In addition to both crash flights seemingly losing control whilst attempting a turn, both occurred after take-off with "elevated load factors"(assuming it applies to aircraft weight, not aerodynamic loading)

Beyond that, I'm still waiting for a 737 jockey to explain the full significance of those words.
Nothing to see here; move along please.
 
dare100em
Posts: 275
Joined: Tue Dec 23, 2014 9:31 am

Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 11:55 am

XRAYretired wrote:
journeyperson wrote:
dare100em wrote:
Bjorn has an article on LH which I foun very enlithening at least:

https://leehamnews.com/2019/03/22/bjorn ... sh-part-2/


"Blowback". Just when you thought it couldn't get any more complicated!
.

Hmm. The article is talking elevator blowback. Would assume elevators are rod actuated, so would also suspect this is possible for the elevators. Can anyone confirm this and what sort of airspeed and AOA this would occur? However, the article does not refer to stabilisers. Would assume stabilisers are ball-screw actuated? and anyway we know they were trimmed nose down (FDR for ET610, Inspection for ET302).

So I would guess its not a significant factor except maybe preventing recovery using the yoke alone.


Ray


It was the final nail to the coffin when the airspeed got to high and therefore the elevators, which would normally be capable of countering the (MCAS) down inertia of the tail by pilot upward force of the elevators lost its function (due to the higher and higher airspeed with the nose down). That seems very logical to me.
 
AviationBob
Posts: 14
Joined: Sun Mar 10, 2019 1:14 pm

Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 1:15 pm

PlaneInsomniac wrote:
AviationBob wrote:
[Hence, why it's so important to have "Good" Pilots who are well trained and experienced enough to figure out that if you have what appears to be a runaway stabilizer, that maybe you should give the cut-out switches a try.


Seriously, this again?

Problem is, it wasn't a "runaway stabilizer".

It was an unanticipated, intermittent failure mode of a faultily designed, undocumented and not properly certified system. MCAS, which had never been properly explained to them, changed the trim in bursts unpredictable for the pilots, in a stressful situation amidst other (aural) warnings and malfunctions.

Even "good" pilots likely wouldn't have been able to identify and remedy this unexplained behaviour from an undocumented system among various other malfunctions in the brief moments (in one case less than a minute IIRC) between when trouble started and the subsequent crash.

Particulary scary is the statement in https://leehamnews.com/2019/03/22/bjorn ... sh-part-2/ concerning the JT crash: Absent any help from the handbook, the crew was actively working to counteract the seemingly random trim changes, and had actually discussed the issue. However, "The FO trimmed, but he did it in too short periods". None of this could have been understood or solved even by a "good" crew.

The truth is, the MAX has been flying safely elsewhere because many other airlines paid additional money for further sensor malfunction indicators, which Boeing - it now seems: criminally - sold as optional extras for their buggy, semi-secret and self-certified MCAS.

Face it: This one is 100% Boeing's fault, even if some hypothetical perfect pilot may have had a miniscule chance of saving the day.

One.
Hundred.
Percent.


I’m just glad you won’t be any part of the accident investigation team. I’m glad we will most likely have a professional team of people who will look at ALL aspects that contributed to the crash, not hell-bent on just putting the screws to Boeing and putting the flight crew up on a pedestal, not even considering that they may have made mistakes too. If it takes a “perfect” pilot to figure out that a bunch of uncommanded horizontal stabilizer trim movements might suggest a problem with the auto-trim, then we are all in trouble.
 
User avatar
speedbored
Posts: 2207
Joined: Fri Jul 19, 2013 5:14 am

Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 1:21 pm

AviationBob wrote:
I’m just glad you won’t be any part of the accident investigation team. I’m glad we will most likely have a professional team of people who will look at ALL aspects that contributed to the crash, not hell-bent on just putting the screws to Boeing and putting the flight crew up on a pedestal, not even considering that they may have made mistakes too. If it takes a “perfect” pilot to figure out that a bunch of uncommanded horizontal stabilizer trim movements might suggest a problem with the auto-trim, then we are all in trouble.

If the theory put forward in this article is correct (and it seems very credible) then it seems that no matter how experienced the pilots were, the issue might just have meant they both had both hands full just trying to apply enough elevator to prevent a rapidly accelerating dive.

Easy to blame pilots for not doing something simple if you ignore the circumstances they found themselves in, and the very short amount of time they had.

https://leehamnews.com/2019/03/22/bjorn ... sh-part-2/
 
BravoOne
Posts: 3602
Joined: Fri Apr 12, 2013 2:27 pm

Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 1:33 pm

smartplane wrote:
BravoOne wrote:
KlimaBXsst wrote:
So... NO MAX 737 sim time for the 29 year old pilot.

Which airlines in the US and Europe were allowing their pilots to fly the MAX 737 with NO MAX sim time?

Sorry if it’s been mentioned already but this thread is now quite long.



Don't think SWA has an approved MAX sim yet, nor for that matter UAL or AA? As a matter of fact, I don't believe the original design specs for the sims include the ability to emulate a MCAS failure as it was never meant to be a player. I'm confident the the first batch of sims built for Boeing do not replicate this feature.

Based on comments earlier in this thread, probably the biggest difference in NG v MAX simulators until now, is the MAX logo. Has the media got it's hands on a MAX simulator yet to test out any theories?



Since when does the media have anything to do with accident investigations? Giime a break!
 
mjoelnir
Posts: 8524
Joined: Sun Feb 03, 2013 11:06 pm

Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 1:43 pm

BravoOne wrote:
smartplane wrote:
BravoOne wrote:


Don't think SWA has an approved MAX sim yet, nor for that matter UAL or AA? As a matter of fact, I don't believe the original design specs for the sims include the ability to emulate a MCAS failure as it was never meant to be a player. I'm confident the the first batch of sims built for Boeing do not replicate this feature.

Based on comments earlier in this thread, probably the biggest difference in NG v MAX simulators until now, is the MAX logo. Has the media got it's hands on a MAX simulator yet to test out any theories?



Since when does the media have anything to do with accident investigations? Giime a break!


The media have to do with information. What has finding out what a 737MAX simulator does, to do with accident investigation?
 
BravoOne
Posts: 3602
Joined: Fri Apr 12, 2013 2:27 pm

Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 2:10 pm

I assume english is not your first language as your post does not make sense. That's okay as I think we are on the same page?

As for sim capabilities for the MAX, one would have to imagine that MCAS is missing from most if not all of them since, Boeing sell the data packages to the various manufactures.
 
ikramerica
Posts: 14900
Joined: Mon May 23, 2005 9:33 am

Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 2:17 pm

glideslope900 wrote:
scbriml wrote:
PixelPilot wrote:

I would say that's not shade as you say it but facts that initially a lot of people dismissed because hey lets hate on boeing.
Give it time. Things will balance.


More casual racism in the article.

The last para finishes:
"We don’t know how many other pilots may share these feelings … however when you look at these against the potential training problems with the 737 Max, training that the FAA said could be done through an iPad course, and the lack of 737 Max simulators, these don’t paint a very rosy picture of how Ethiopian Airlines views safety,” he said.

The issues listed there apply to just about every airline flying 737MAX in the World.


Except no other airline in the world crashed a 737MAX (except Indonesia). Why does everyone immediately resort to crying “racism” over any critisizm of a non-western country?

Because despite Ethiopias long and documented storied history of government corruption including very recent events, they are beyond reproach, because racism.
Of all the things to worry about... the Wookie has no pants.
 
osiris30
Posts: 2655
Joined: Sat Sep 30, 2006 10:16 am

Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 2:17 pm

speedbored wrote:
osiris30 wrote:
patplan wrote:

To partially answer your question, here's the partial graph found on page 14 of the NTSC's Preliminary Report of its investigation:

Image

Yes, stick shaker had showed up way before MCAS is activated...Although there are more than a couple of blips of MCAS activation when the flap is on?? Curious.


You are misreading the graph. That is a shared line for STS and MCAS. Both are in yellow. The blips are STS.

To be fair, there's no way to differentiate between STS and MCAS adjustments on that graph.


I know because the graph is for electriconic trim in general. I was pointing that out since the parent was reading it incorrectly.
I don't care what you think of my opinion. It's my opinion, so have a nice day :)
 
afgeneral
Posts: 93
Joined: Sat Jul 02, 2016 2:43 pm

Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 2:30 pm

XRAYretired wrote:
glideslope900 wrote:
scbriml wrote:

More casual racism in the article.

The last para finishes:
"We don’t know how many other pilots may share these feelings … however when you look at these against the potential training problems with the 737 Max, training that the FAA said could be done through an iPad course, and the lack of 737 Max simulators, these don’t paint a very rosy picture of how Ethiopian Airlines views safety,” he said.

The issues listed there apply to just about every airline flying 737MAX in the World.


Except no other airline in the world crashed a 737MAX (except Indonesia). Why does everyone immediately resort to crying “racism” over any critisizm of a non-western country?


The PIC of the Indonesian aircraft was an Indian and the PIC of the Ethiopian aircraft was an Indonesian.The Plot thickens!


There must be an Indian plane with an Ethiopian PI somewhere...
 
OlafW
Posts: 304
Joined: Sat Jul 11, 2009 6:15 pm

Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 2:44 pm

SheikhDjibouti wrote:
I've posted this before.
Boeing MOM -18-0664-01B dated 11 Nov 2018
The MCAS functions commands nose down stabilizer to enhance pitch characteristics during steep turns with elevated load factors and during flaps up flight at airspeeds approaching stall

In addition to both crash flights seemingly losing control whilst attempting a turn, both occurred after take-off with "elevated load factors"(assuming it applies to aircraft weight, not aerodynamic loading)

Beyond that, I'm still waiting for a 737 jockey to explain the full significance of those words.


Thanks for the repost, it's hard to follow up on every single post. So stabilizer movement during a turn is no problem and rather a normal occurence - unless there was some malfunction here.
 
User avatar
JetBuddy
Posts: 2223
Joined: Wed Dec 25, 2013 1:04 am

Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 2:47 pm

My father who's a very experienced airline captain (for 30 + years) had this take on the situation:

"The aviation authorities and the aircraft manufacturer slept with each other because it felt good for both of them. The result was two accidents and a disasterous reputation".
 
kengo
Posts: 278
Joined: Mon Apr 08, 2013 11:04 am

Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 3:07 pm

SheikhDjibouti wrote:
Boeing MOM -18-0664-01B dated 11 Nov 2018
The MCAS functions commands nose down stabilizer to enhance pitch characteristics during steep turns with elevated load factors and during flaps up flight at airspeeds approaching stall

In addition to both crash flights seemingly losing control whilst attempting a turn, both occurred after take-off with "elevated load factors"(assuming it applies to aircraft weight, not aerodynamic loading)

Beyond that, I'm still waiting for a 737 jockey to explain the full significance of those words.


Any right minded 737 pilots will not response to you request, and there are a few of them in this forum, because if one of them expressed something different from what some members expect, he or she gets clubber by the "want to be pilots" or by those that think they know more than the pilots because they read this and that on the net. It is a sad fact and most likely the reason why so many of our resident pilots don't participate on air crash threads. Even if they participate early in the discussion, they tend to take a sideline view once the thread goes off track, which happen more times than not.

Just saying....
 
jollo
Posts: 381
Joined: Mon Aug 08, 2011 7:24 pm

Re: Ethiopian Airlines 737MAX crashes enroute to Nairobi

Fri Mar 22, 2019 3:18 pm

dare100em wrote:
It was the final nail to the coffin when the airspeed got to high and therefore the elevators, which would normally be capable of countering the (MCAS) down inertia of the tail by pilot upward force of the elevators lost its function (due to the higher and higher airspeed with the nose down). That seems very logical to me.


I'm beginning to picture this scenario:
    * you have a malfunctioning AOA sensor, which basically by random misfortune happens to be the one feeding STS and MCAS for this flight (the other one works just fine, but is being ignored)
    * you get no warning of the failure, because your cheap-o third-world airline did not purchase the AOA disagree warning option
    * instead, you get stick shaker and stall warning
    * so you push a bit of nose down (and perhaps add a little thrust) to build a safety speed margin above an airspeed you're suddenly no longer sure about
    * MCAS - which you may or may not know about, certainly not through reading the FCOM - silently kicks in and gives you 2.5°/sec of nose down trim for 10 seconds - speed increases quickly
    * you may have noticed - amid the cacophony of alarms, perhaps while trying to run an unreliable airspeed checklist - the uncommanded trim movement, but then it stops on its own - so no, this is not a runaway stab trim occurence
    * you pull back on the yoke to avoid overspeeding, and probably trim nose up to alleviate the effort - but not for a full 10 seconds: stab trim is still nose down and speed is not back down to where it started
    * after 10 seconds MCAS is back in action, and gives you another 10 seconds of nose down trim - speed increases further
    * you're now pulling back on the yoke with all your might, but blowback kicks in and despite your best efforts the elevator looses authority

At this point you have just one chance of living through the day by executing this exact sequence of actions:
1) do not heed the backseater pilot deadheading on the jump seat behind you, yelling to cutoff stab trim! At least not yet: if you do, you will not have enough elevator authority to climb out of the dive you're currently in; you need electric trim because hand cranking the manual trim wheel will not be fast enough, and you need both hands to apply as much nose up elevator as you can in the meanwhile
2) use electric trim switch to trim nose up and continue to pull back on the yoke (something they taught you since PPL should not be done: first stick, then trim)
3) if you aren't a smoking hole in the ground by now, get speed under control and back to level flight eventually
4) NOW you must cutoff the stab trim to avoid riding the rollercoaster again

Creepy, and sobering.

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