Ethiopian Airlines Boeing 737 MAX crash

ancienturion

LE
Book Reviewer
How much longer before Boeing shares are worth buying?
 
From the basic physics point of view... if the new engines move the CoG too far back wouldn't you

1) lengthen the wingroot
2)attempt to reduce weight aft of the wingroot
3)Use Ballast

Rather then include a system that makes uncommanded trim adjustments?

just from the simple moments point of view I know next to jack about aerodynamics....
 
Aviation authorities make a great deal of money from overflight fees/navigation fees/recalibration of navaids/charging airlines for supposedly overseeing overhauls and issuing an ARC / registration fees /approval of airports and so on, so that they don't have to deal with the messy business of actually looking inside aircraft undergoing overhaul. Essentially, once an aircraft is non-commercial, they cant extract a whole lot of value from it so regulation and oversight of small GA is farmed out to the relevant organisations such as the LAA in the UK, EAA in America, ILAS in Ireland and so on. It's open season on anything or anyone that flies or fixes for a living. It has long since been a race to the bottom and the only miracle is that there haven't been more hull losses with deaths.
 
From the basic physics point of view... if the new engines move the CoG too far back wouldn't you

1) lengthen the wingroot
2)attempt to reduce weight aft of the wingroot
3)Use Ballast

Rather then include a system that makes uncommanded trim adjustments?

just from the simple moments point of view I know next to jack about aerodynamics....[/QUOTE

1. Large redesign, precisely what they’re trying to avoid. Wouldn’t work though, moves chord line and therefore Centre of Pressure forward.

2. Ditto.

3. Hush your mouth. Weight reduction is the holy grail. Carrying non paying weight is practical but heresey the airlines would never countenance.

Good thinking though. Something not enough people seem to do these days!
 
IMG-20190409-WA0002.jpg
 
For those comparing the Ethiopian to the AirFrance crash, this is the difference - the MCAS didn't really say, ok, I give up or alert the pilots. And it can be counter intuitive, but like it says, that's where you start earning money. But if the median reports are right and MCAS was fed by one sensor - I am surprised as hell. Aviation goes for double and usually triple redundancy.

Click for the right time at the video.


And a lot of poor CRM.
 
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From the basic physics point of view... if the new engines move the CoG too far back wouldn't you

1) lengthen the wingroot
2)attempt to reduce weight aft of the wingroot
3)Use Ballast

Rather then include a system that makes uncommanded trim adjustments?

just from the simple moments point of view I know next to jack about aerodynamics....
Personally I would adopt the same MO as I used on my Airfix kits. Squirt lighter fuel on them and set them afire.
 
How much longer before Boeing shares are worth buying?
My earnings were down this past quarter by about 35% from Q4, but only about 10% from Q1 last year. It is rather interesting that I am also down about $60 a share since the accident, but overall, up $60 a since the end of Q4-2018. Having acquired most of my shares quite some time ago, my average cost per share is ~$100, so I am still up ~$280/share.
 

Bagl0ck

On ROPS
On ROPs
My earnings were down this past quarter by about 35% from Q4, but only about 10% from Q1 last year. It is rather interesting that I am also down about $60 a share since the accident, but overall, up $60 a since the end of Q4-2018. Having acquired most of my shares quite some time ago, my average cost per share is ~$100, so I am still up ~$280/share.
Stick with them. If you're in it for the long haul rather than speculating which it sounds like you are
 
Initial accident report published:

http://www.ecaa.gov.et/documents/20435/0/Preliminary+Report+B737-800MAX+,(ET-AVJ).pdf/4c65422d-5e4f-4689-9c58-d7af1ee17f3e

Bottom line, crew did as trained. The bulletin from Boeing at the end of the document makes my blood run cold.
How so? It is noted as evidence that Boeing updated and/or re-enforced protocols for this particular failure after the Lion crash and less than 2 weeks before this one, which means the possibility of this type of failure was acknowledged and should have been fresh in the minds of everyone concerned.

The really scary part of the report is that the data recorders do not apparently record the actions of turning off both cutout switches, but the report does note:

At 05:40:35, the First-Officer called out “stab trim cut-out” two times. Captain agreed and FirstOfficer confirmed stab trim cut-out.

At 05:40:41, approximately five seconds after the end of the ANU stabilizer motion, a third instance of AND automatic trim command occurred without any corresponding motion of the stabilizer, which is consistent with the stabilizer trim cutout switches were in the ‘’cutout’’ position.
Which was followed a page later with:

At 05:43:11, about 32 seconds before the end of the recording, at approximately 13,4002 ft, two momentary manual electric trim inputs are recorded in the ANU direction. The stabilizer moved in
the ANU direction from 2.1 units to 2.3 units.

At 05:43:20, approximately five seconds after the last manual electric trim input, an AND automatic trim command occurred and the stabilizer moved in the AND direction from 2.3 to 1.0 unit in
approximately 5 seconds. The aircraft began pitching nose down. Additional simultaneous aft column force was applied, but the nose down pitch continues, eventually reaching 40° nose down. The stabilizer position varied between 1.1 and 0.8 units for the remainder of the recording.
This being consistent with the stab trim cutout switches being reset to automatic operation in contravention of established protocols. Rather difficult to accidently move the blocking plate out of the way then accidently throw both switches back up...

Meaning, Crew did not do as trained.

Of course since switch positions and signal (or lack of) is not captured, simply reading what is recorded as consistent with strange behaviour on the part of the co-pilot is not the only option. It also leaves the highly improbable second possibility that the control program gained sentience and decided on it's own to reprogram itself to disregard the cutout switches, which it had previously yielded control to, in order to commit suicide.
 
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How so? It is noted as evidence that Boeing updated and/or re-enforced protocols for this particular failure after the Lion crash and less than 2 weeks before this one, which means the possibility of this type of failure was acknowledged and should have been fresh in the minds of everyone concerned.

The really scary part of the report is that the data recorders do not apparently record the actions of turning off both cutout switches, but the report does note:



Which was followed a page later with:



This being consistent with the stab trim cutout switches being reset to automatic operation in contravention of established protocols. Rather difficult to accidently move the blocking plate out of the way then accidently throw both switches back up...

Meaning, Crew did not do as trained.

Of course since switch positions and signal (or lack of) is not captured, simply reading what is recorded as consistent with strange behaviour on the part of the co-pilot is not the only option. It also leaves the highly improbable second possibility that the control program gained sentience and decided on it's own to reprogram itself to disregard the cutout switches, which it had previously yielded control to, in order to commit suicide.
How so? You answered the question yourself: The possibility of this failure was acknowledged which is a long way from identifying why and even further away from actually doing something to rectify it.

Re the Stab Trim Cutout, I’m of the view that the switch position is unmonitored by FDR. My reasoning here is that just about every other crew action re switch selection is recorded, Heading, Alt Window, control column trim inputs etc. Either that or in their quest to not apportion blame as per their (laudable) Mission Statement, the Authorities have not committed on that in this, the Initial Report. I find that hard to believe though given the crucial nature of the system to the investigation.

It is possible that the subsequent control column Stab Trim inputs you mention (post the apparent Stab Trim Cut Out selection) are the result of the FDR sensing switch position rather than actual Stab position? It is a pretty much Pavlovian response for any pilot to try and trim out any control column forces, much emphasised from the very earliest stage of training so trim inputs may have been subconscious but unproductive as even though the switches were moving (and being sensed by the FDR as moving) they weren’t actually doing anything as the system was isolated by the Cut Out?

I find it difficult to believe they put the Cut Out switches back to auto as a) as you say that’s contrary to Procedure and b) they already knew that the flight control system was behaving oddly with it in Auto which is why the went to Cut Out in the first place. There is I suppose the possibility that they were in such extremis that they decided to try anything but again, a report that is fairly detailed on crew comms and actions makes no suggestion this was discussed, never mind actioned.

I’m also bemused by your comment re the strange behaviour of the FO? In what way?

As an aside, I’ve met a fair few Ethiopian guys at Boeing Flight Training (can’t confirm Boeing do the Type Ratings on the MAX but they do on the 777/787.) They struck me as highly competent guys which I’m ashamed to admit flew very much in the face of my preconceptions regarding standards in Africa generally. Very loose I know but I reckon these guys were competent, well trained and unlikely to have gone outside their training. The report refers to the more general Ethiopian operation and it appears far from 3rd World?

In short, these guys did as they were trained but were outmanoeuvred by an automated system designed to do just that, take the pilot out of the loop. The assumption that it “over reacted” puts them in an essentially unrecoverable situation particularly as (I believe) the system in question operates outside of the conventional Stab System? If that is the case, the system is independent of the conventional Stab system, in real life function rather than in design then the Boeing guidance is surely irrelevant?
 
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How so? You answered the question yourself: The possibility of this failure was acknowledged which is a long way from identifying why and even further away from actually doing something to rectify it.
No functional redundancy with AoA sensors, intermittent failure observed, yet not replacing said very important, non-redundant sensors when issues arise... This seems to be the theme...

Re the Stab Trim Cutout, I’m of the view that the switch position is unmonitored by FDR. My reasoning here is that just about every other crew action re switch selection is recorded, Heading, Alt Window, control column trim inputs etc. Either that or in their quest to not apportion blame as per their (laudable) Mission Statement, the Authorities have not committed on that in this, the Initial Report. I find that hard to believe though given the crucial nature of the system to the investigation.
I pointed out that both switches' states are not monitored/recorded, hence the reports' stated assumption that the cutouts were apparently activated because the AND command was ignored ~5 seconds after the voice recording of the "cutout" order.

Had states been recorded, they would have been in the data lines shown in the report instead of making that assumption in the very important, initial, official report. That it is "assumed" correct actions were taken when the data showed what was expected, and not brought up at all when data showed that auto was apparently functioning again after around three minutes (with incorrect inputs again initiating the nose dive) shows to me that they are obfuscating pilot error, as if the states of the switches WERE recorded, and it was still cut-out position (and not Auto) then it would definitely show a problem with the Flight Control Computer's routines disregarding the cut-out, and not strange pilot behaviour.

It is possible that the subsequent control column Stab Trim inputs you mention (post the apparent Stab Trim Cut Out selection) are the result of the FDR sensing switch position rather than actual Stab position? It is a pretty much Pavlovian response for any pilot to try and trim out any control column forces, much emphasised from the very earliest stage of training so trim inputs may have been subconscious but unproductive as even though the switches were moving (and being sensed by the FDR as moving) they weren’t actually doing anything as the system was isolated by the Cut Out?
Instructions are to manually enforce ANU against the auto system in the event of a runaway event before CUT-OUT which disables the both the auto system and the manual (electric) system.

The manual (electric) inputs of the pilot(s) were recorded, as were the automatic inputs from the FCC. The FCC input for AND was shown as ignored 5 seconds after the voice recording of cut-out commands. This would seem to indicate that this was correctly handled. The pilots' final manual (electric) ANU commands ~3 minutes later (which should have been locked out) appear to have had a very slight effect, and the FCC AND inputs (which should have been locked out) shown again 5 seconds later seem to have full effect, which apparently pushed the aircraft over the edge as the trim dropped to stay at around 1 unit after which the Pitch Attitude progressively fell off all the way into the ground for the next ~35 seconds.

It looks like the co-pilot tried manual ANU which failed, then flipped the CUT-OUTs off, allowing the final FCC AND to be followed 5 seconds later.

However, it should be noted that the column commands seem to have been attenuated the entire course of the flight, weird.

I find it difficult to believe they put the Cut Out switches back to auto as a) as you say that’s contrary to Procedure and b) they already knew that the flight control system was behaving oddly with it in Auto which is why the went to Cut Out in the first place. There is I suppose the possibility that they were in such extremis that they decided to try anything but again, a report that is fairly detailed on crew comms and actions makes no suggestion this was discussed, never mind actioned.
Either the co-pilot put the switches back into auto, or the system somehow gained the ability to ignore the switches after ~3 minutes of not being able to do so.

I’m also bemused by your comment re the strange behaviour of the FO? In what way?
How many times does this need to be pointed out?

Also, he had a grand total of 361 hours, in about 4 months, not much experience. Perhaps he flipped the system back on because the manual trim was not functioning when it wasn't supposed to be, after the Captain asked him to verify it wasn't functioning?

In short, these guys did as they were trained but were outmanoeuvred by an automated system designed to do just that, take the pilot out of the loop. The assumption that it “over reacted” puts them in an essentially unrecoverable situation particularly as (I believe) the system in question operates outside of the conventional Stab System? If that is the case, the system is independent of the conventional Stab system, in real life function rather than in design then the Boeing guidance is surely irrelevant?
As a very critical component due to the nature of the new beast that is MAX, I think it is wrong that the AoA sensors are not triple redundant. There should be three on both channels/sides.

I also think the failure mode of operation in this scenario might push a bit beyond the capabilities of the modern, lightly experienced, civilian airline pilot.
 

Bagl0ck

On ROPS
On ROPs
A wealth of whistleblower links and articles on reddit for those interested in a deep dive

 
The Boeing PR bods are putting in triple shifts at present. This is a calculated move to put the public at ease and give the airlines reasonable grounds to get the aircraft back in the air quickly and with the minimum of retraining.

The latter point ignores the supreme irony that if, as Boeing alleges pilots are so incompetent then clearly they need a very great deal of retraining.

The Regulatory Authorities, having been found out as exercising neither of their titular duties will do nothing as to do something would be tantamount to an admission of failure and that would never do.

The only challenges to this appalling state of affairs is coming from world wide pilot unions.
 
Not 737, but found it funny with the quip. Typical Aussie statement...

"That's a shit fart out there, I think I have broken my nose."

Example of another automation issue which could've gone so wrong - from Airbus.

 
https://transportation.house.gov/imo/media/doc/Sully Sullenberger Testimony.pdf

Spot on IMHO. If the name rings a bell, it’s the bloke that ditched the Airbus in New York after losing both engines having flown into a flock of geese.

Meanwhile, Boeing are still trying to shift the blame onto the pilots. Of particular interest in the above article is the difference in how the MCAS trim worked, not as a consistent application of trim as in a Stab Trim Runaway for which there is a checklist and for which event pilots are trained and should therefore be able to act appropriately but in a random and very aggressive way for which there isn’t a checklist, the pilots weren’t trained to deal with (a deliberate decision to cut conversion costs to airlines?) and therefore arguably they were not in a position to respond appropriately.

In short, they were taking a running Fuck at a rolling doughnut.

Battle over blame
 
This article in the Seattle Times gives an insight into the culture prevailing in Boeing in relation to putting the 737 MAX into service as soon as possible, despite issues being identified in the design of the 737 MAX.

The inside story of MCAS: How Boeing’s 737 MAX system gained power and lost safeguards

New Boeing 737 MAXes are being flown into storage at Kelly Air Force Base in Texas. Not an ideal location for this purpose, and any airplane stored here for an extended period is likely to suffer problems in later life as a result of being stored in the prevailing environment at Kelly-which in near San Antonio.
 

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