Breaking news: Ethiopian Airlines flight has crashed on way to Nairobi

[Evan]

My conclusions:
- I will let Evan and TeeVee discharge his rage on Boeing's design, and I will agree. I want to focus on the pilot's actions GIVEN the airplane design and what was known form the Ethiopian crash.
- The MCAS and trim system worked as bad as it is designed to but not worse than that. For example, these bad things speculated in the forum did NOT happen:
--- MCAS acting in conditions other than manual flight with flaps retracted.
--- MCAS acting when the thumb switch was actuated.
--- MCAS not stopping when the thumb switch was actuated.
--- MCAS acting with the trim cutout switches moved to the cutout position.
--- The electric motor not being able to move the stabilizer in extreme-force conditions.
--- Limitations on the authority of range of the trim when using the thumb switches.
--- The stabilizer failing moving in response to the trim thumb switch (with the cutout switch in the operational position).
- For unknown reasons, the pilots did not re-trim the plane before resorting to the cutout switches.
- For unknown reasons, for more than 1 minute, when the speed was already high but not so high, the pilots did not seem to attempt to operate the trim wheel manually after disconnecting the cutout switch, even when the plane was severely out of trim. By when they attempted it, the plane was going to fast and the wheel was too hard to move manually.
- When the situation became desperate, the re-connected the cutout switches. The only logical explanation for that would be that they would attempt to use the thumb switch to re-trim the plane. Yet:
- They did not apply nose-up trim except for 2 supper-brief clicks on the thumb switch. The stabilized did respond accordingly moving an insignificant little bit nose-up.
- When the MCAS started to trim down again, they did not attempt to use the thumb switch to stop it. The nose-down trim automatic actuation would have been super evident not only by the turning of the trim wheels but also by the increased force on the control column (with which they amazingly managed to move the control column further back) and the yet uncontrollable quick nose-down pitch.
- With both pilots pulling hard on the control column together and being unable to control the pitch-down, they didn't attempt to use the thumb switch to trim up.
- Any of the previous 6 bullets would have saved the flight and the lives. (Also a sound design would have, but I leave that to Evan and TeeVee)
- All of the previous 6 bullets were known from the Lion Air crash
(the part that was not known was that it could be impossible to turn the trim wheel manually in extreme conditions)

Here's my take-away:

• The crew's failure to reduce thrust (despite overspeed warning) and their failure to counteract trim prevented them from recovering.
• The crew's failure to do these things is clear evidence that the workload and confusion of this scenario exceeds what Boeing or the FAA can expect from human pilots across the industry.
• The left AoA sensor appears to have been moved by acceleration forces alone, leading me to believe either the vane was bent/detached or was not turning the sensor element itself due to some kind of internal failure (no idea how the sensor works).
• Because of this, the failure did not reveal itself during the take-off roll. The optional disagree light would not have prevented the flight from taking off.
• The AoA sensor may have been damaged due to a bird strike or other impact either on the take-off roll or while on the ground (was there a proper walk-around inspection?).
• The AoA sensor failure that set the events in motion may be entirely different from that of the Lion Air sensor, but with similar ramifications.
• In short, the 737-Max was designed and certified such that a single AoA vane failure (for whatever reason) can result in a loss-of-control situation exceeding the CRM and recovery limits of the average crew. This was reckless and negligent on the part of Boeing and the FAA.

Although pilot error is clearly involved, the pilots can not be blamed under these circumstances. The blame for this accident rests squarely on Boeing and the FAA. However, the correct procedure for this event should be revised as follows:

1. Counter with electric trim (as needed).
2. Reduce thrust.
3. Extend Flaps.
4. Establish reliable airspeed/altitude via the standby instrument.
5. DO NOT use trim cutout switches.
6. DO NOT re-engage autoflight.
7. Stabilize, burn down fuel and return.

Questions:

Did the low-hour FO know how to extend the trim wheel handle?
Did the PIC attempt to assist with the manual trim?

[3WE]

It appears to me that the fatal error here was leaving the thrust at TOGA, despite the overspeed warning.

As usual it appears you are soooooooo focused on procedure that you have no expletive clue about fundamentals...

If you NEED to climb, you usually NEED power- especially if you already have full nose up input! A DC-10 with jammed elevators almost didn't crash because the pilots went to full power...sad story.

If the controls are messing up your ability to climb, very often more power will over come that and give you climb.

Please get out of the bubble and ride a bicycle.


Edit: I must acknowledge the honorable teevee's response to the comment:

and as is his wont, evan finds a way to blame the pilots.

Concur.

[3WE]

Timeline summary with CVR snips

From reading the description in the report, I am troubled- It sounds like they are doing many of the things that we parlour pontificators wished they had done.

And it reads as though it was rather confusing up there with this warning and that- and changes and multiple disagrees.

About the only thing missing from the CVR was an utterance of: "Could this be that crazy behavior that we read about on Jetphotos that crashed the Lion Air guys".

[Evan]

Please get out of the bubble and ride a bicycle.

If you think there is a proper time to overspeed an aircraft, I think you should be the one with the bicycle.

This was not a strategic decision. It was an oversight.

[3WE]

If you think there is a proper time to overspeed an aircraft.

All the words matter, Evan:

When the cargo door blows out on a DC-10 and the floor settles and jams the elevator cables and elevators in moderate nose down setting one crew was just almost able to level off by going to full power...that was a proper time.

Lots of elevators have jammed over lots of years and power has been used to make the aeroplanie go up (or not_go down).

Power = Altitude...terrain warnings going off and them pulling up with all their might... Full power was NOT_an oversight Mr. Robato.

With EVERYTHING ELSE going wrong- SCREW the overspeed warning...hell the underslung engines are going to make me go MORE nose down if I ease back...

[3WE]

The silencing of free speech...

Just a reminder, the removal of Captain Mentour's video is not a huge conspiracy...It's kind of the same reason the FINAL report isn't out...This is a very big deal, and unfortunately, we can be good at taking things out of context and twisting them.

Probably a good move that he takes it down.

If we want to start a go-fund me account and can start our own airline and hire Cap'n M and let him fly AND make youtubes that may have legal implications.

But heck, why waste your employment making vidoes when parlour talk aviation fora cover it fairly well.

[Evan]

MCAS redundancy issues are obviously being resolved. I expect the FAA will also focus on the sensor failure issue, which also affects the NG. The sensor involved was reportedly manufactured by Rosemount Aviation (United Technologies), possibly the UTC Aerospace (Rosemount) Model 0861. The nature of the sensor failures appear to be quite different between the two crashes. On the Lion Air DFDR, the sensor seems to be operating mechanically but reading incorrectly (perhaps a gain error or miscalibration). The Ethiopian sensor seems to be mechanically malfunctional (perhaps physically damaged). It will not surprise me if the two sensor failures are unrelated.

The Lion Air sensor was reportedly a rebuilt spare. According to Bloomberg, the rebuilder was XTRA Aerospace Inc. in Mirimar, FL. Hopefully the investigation will scrutinize the oversight here.

In any case, commercial aircraft components, especially line-replaceable units like this, are expected to fail in service. A single failure should never result in an upset or loss-of-control situation.

[Gabriel]

MCAS redundancy issues are obviously being resolved. I expect the FAA will also focus on the sensor failure issue, which also affects the NG. The sensor involved was reportedly manufactured by Rosemount Aviation (United Technologies), possibly the UTC Aerospace (Rosemount) Model 0861. The nature of the sensor failures appear to be quite different between the two crashes. On the Lion Air DFDR, the sensor seems to be operating mechanically but reading incorrectly (perhaps a gain error or miscalibration). The Ethiopian sensor seems to be mechanically malfunctional (perhaps physically damaged). It will not surprise me if the two sensor failures are unrelated.

The Lion Air sensor was reportedly a rebuilt spare. According to Bloomberg, the rebuilder was XTRA Aerospace Inc. in Mirimar, FL. Hopefully the investigation will scrutinize the oversight here.

In any case, commercial aircraft components, especially line-replaceable units like this, are expected to fail in service. A single failure should never result in an upset or loss-of-control situation.

The Lion Air and Ethiopian AoA failures are clearly different.

The Lion Air faulty AoA was sensing some 2 degrees more of AoA than the good one since installation. The whole previous flight too. But both sensors (good and bad ones) traced exactly the same graphs in the FDR, even short-term transient bumps, except they they were offset all the time by the same constant. It's quite clear that this was either a calibration or an installation issue, not a "failure".

In the Ethiopian crash the sensors were initially showing different AoAs before the take-off roll started, which is normal since there is not enough airspeed for them to align with the air flow. But since the indicated airspeed becomes alive, throughout the take-off roll, initial rotation and lift-off, the 2 sensors traces exactly the same plot (short term bums and increase of AoA during rotation and liftoff) to the point that you cannot tell that there are 2 graphs being traced. Then, shortly after lift-of, the left AoA sensor goes to 74 degrees and stayed stuck there. It was not an offset. It just didn't move anymore. You don't have even the "noise" that can be seen in the right-hand AoA sensor and in both AoA sensors of the Lion Air flight. This was a sudden failure of an AoA vane that was working perfectly up to that point. Mechanical? Electrons? I don't know.

[Gabriel]

Boeing CEO's statements (paraphrasing):

- We are sorry
- MCAS action due to erroneous AoA values was a neccesary paer in the chain of events of both crashes.
- This has to be fixed. We own it. We know how to do it. And we will do it so accidents like this never happened again

Boeing CEO's non-statements

- Not only we got the MCAS wrong. We got the product design, development, testing and certification wrong.
- These kind of systemic process and policy gaps may have created and may create in the future more mistakes, which may include safety-critical issues.
- Because of that we are reviewing the whole 737 MAX design, development, testing and certification process and the decisions that were taken.
- We are also reviewing our design, development, testing and certification process and policies so flaws like this never happen again or, at minimum, they are not the result of active decisions taken.
- We are at minimum partially responsible for the loss of the lives in these two crash. We recognize that and we are taking full accountability.
- We are being sued by the families of the victims. But I can assure you that there will be no lawsuit.
- That's because we recognize that their claim is fair, and we are going to honor them.
- We are meeting individually and collectively with each and every next of kin and family of the victims of these 2 accidents, we are addressing their immediate needs and working out an economic compensation to their satisfaction.
- Nothing will ever replace the lives lost, but the best we can do is take care of these families in a fair way, assume our responsibility, and make sure that we learn the lessons and identify, address, and fix the issues so as not only as there is never an MCAS accident again, but there is never another accident caused by bad product design, development, certification and testing. Then the loss of lives would not have been vain.
- Boeing is suffering and will continue to suffer a lot from the mistakes we ourselves created, but we are learning from them and we will emerge from the crisis as a stronger company.
- As the head ob Boeing, I am responsible for a leadership structure and style the led to these events. And I take full accountability.
- Here is my undclinable resignation, and I will not accept any golden parachute.

[Evan]

Boeing CEO's non-statements

You forgot:

- Because the 737-Max brand is currently—perhaps indelibly—tarnished as being a flying death trap as a result of our reluctance to address its weaknesses by grounding it after the first crash, we will be returning in full all deposits and cancelling orders without penalty for undelivered aircraft to any customer that wished to do so.

[Gabriel]

You forgot:

- Because the 737-Max brand is currently—perhaps indelibly—tarnished as being a flying death trap as a result of our reluctance to address its weaknesses by grounding it after the first crash, we will be returning in full all deposits and cancelling orders without penalty for undelivered aircraft to any customer that wished to do so.

I didn't forget. I think the MAX will be an excellent and very safe plane.

[SmoothAir]

I think it is quite clear. They were desperately trying to keep the nose from going down. The captain asks for help from the FO to pull up and the FO helps but the captain says that the pitch is not enough. They desperately needed to trim up and they had already tried the trim wheel manually only to find it impossible to move. They needed to revert to the trim switch. For me the real unanswered question is, why didn't they revert to the trim switch then, after re-engaging the trim cutout switches? They payed for that mistake with their lives.

Gabriel, I think the assumptions you are making are based on the fact that you believe the MCAS was working as intended - in regard to inputs and sensors. However, I personally believe the findings will be that the mcas did NOT work as intended (allowing for the erroneous sensor inputs) - I believe this is where the problem is primarily at fault. I cannot, for one second, believe that the pilots would re-engage - as a last attempt - the trim motors only to give a brief press- nonsensical !. Personally, I believe the system overrode these inputs. That when the mcas was initialised (at trim cutout reselect - that it acted in a controlling and over-riding way. Yes, pure speculation, but based on common sense from the reports (otherwise at this moment no reason to explain the brief inputs unless the system the (Make Corpses And SPLAT) was over-riding - perhaps on startup 'reboot' from a trim cutout event. it simply makes no sense.
I also believe pilots may well try to apply thrust in the even of a non (apparent to them - or non controllable event) in the MAX due to its propensity to pitch up during power application due to the engine positions - - a sort of 'power on and let the engines bring the damn thing up!' - which would happen as it is inherently unstable in pitch and power, butm known that due to the placement of the thrust vector a pitch up would normally occur. Obviously it did not do enough to save things due to a final overriding downward force from the stab. However, as said, it is not unreasonable to apply power - dramatic power, in a MAX if you simply cannot correct the downward pitch.
I commend you listing the possible unknown aspects, however, system override and intercept from a rebooted or re-engaged MCAS - or simply - am out of spec (bugged) mcas action is also readily apparent.
I can only hypothesise that on re-engaging the pitch trim that the reason is was so brief was simply that the MCAS had control and not the trim switches - hence brief and immediate abandonment of that manoeuvre. Speculation ? of course. Am I wrong, of course I could be, but ................... you well placed post raises more frightening questions than it answers in my very humble opinion. As I opined before, I really believe there is a major bug in the MCAS that allows it to override the pilot trim - it may only occur on restart from trim cutout - who knows ? - but there is definitely something very very amiss.
We could ALL be totally wrong, however..... when will we see what actually happened and not the sanitised version ?

I commend you for the extremely well presented and researched (and knowledge based) posts.
SA.

[SmoothAir]

In nearly 100% of ALL accidents of EVERY type, someone will easily work out the steps that would have avoided the accident to begin with. When I was cutoff by a taxi in 2012 while on my enduro bike, had I leaned hard, turned and jumped the curb before attempting to brake instead of attempting to brake only to find that my knobby tires didnÂ’t offer enough friction on asphalt to stop in time, I wouldnÂ’t have 21 screws and 3 plates in my ankle. So I guess I am to blame. Never mind the taxi who changed lanes illegally and then stopped to block a lane of traffic illegally.

ItÂ’s easy to armchair these things after the fact, when one has all the time in the universe to think about what was happening and what should be done. ItÂ’s easy to say, memory items, qrh, crh and all the other acronyms you care to.

I watched Juan brown’s last video, and strangely absent was any placement of blame on pilot action or inaction. Maybe he realizes that humanity of every pilot—something evan seems incapable of...

But if youÂ’re gonna armchair, preface your genius with the absolute truth: Boeing, in a GROSSLY negligent manner, place these (and others) pilots in a position they should NEVER have been in. All for the sake of $$$ and making shareholders happy. Boeing, and NO ONE ELSE, well maybe some turds at the faa, are 100% the cause of the 364 deaths, as well as the enormous loss of revenue airlines around the world have been and will continue to endure.

so true ! bravo !

[SmoothAir]

The Trump Factor.
What all here need to realise as well, is the idiot factor in the final 'solution' if it ever gets there - that is Don the Con..

Not, how he 'announced' the grounding (not because his personal pilot would not be accepted for the head honcho FAA job ????!!!) - he wanted to 'own it' as he wants to own everything. He is of dubious IQ - low by all signs - a pathological liar, a con man, a cheat and an illiterate numbskull. .. now, when this starts to make sense (the whole MAX fiasco) then Don the Con will try to make it anyone elses issue apart from his own - or in this case - boeing !. that intransigence will simply make respected and intelligent leader of the free world refuse to accept his lies and promises. The saga will go on BECAUSE of trump interfering in things that have jack shit to do with him.
He is likely to drive a stake into boeing's heart in his attempt to override all actual facts and say that it is safe with one line of code and a bandaid. The guy is an utter moron!!!, yet, will play a key roll on all this, as he is genetically deformed enough to do so.
Instead of correcting and managing (spinning even!) a tragedy, he will simply lie and attempt to con. The REAL leaders of the world who are FULLY aware of this idiot's silly games and will not let it go. --- I mean ? wasn't Boeing actually Born (created) in Germany (sic) - like his racist father ? lol .////

It brings a whole new dimension to improving safety when you have a narcissistic pathological liar MAKING himself in charge - even after he sacks his patsy..... You ain't seen nothing yet boys and girls, the Don the Con show will go into full gear soon. - Dont buy more MAX's - ???? we will add TARIFFS !!! F&*ING MORON.

[Black Ram]

Now this is interesting. The Department of Justice has subpoenaed Peter Lemme, a former Boeing engineer who has worked on the 737-100/200 flight control system.

https://theaircurrent.com/aviation-s...nvestigations/